linux/drivers/acpi/acpi_lpss.c

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ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org>
2013-03-07 06:46:20 +08:00
/*
* ACPI support for Intel Lynxpoint LPSS.
*
* Copyright (C) 2013, Intel Corporation
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org>
2013-03-07 06:46:20 +08:00
* Authors: Mika Westerberg <mika.westerberg@linux.intel.com>
* Rafael J. Wysocki <rafael.j.wysocki@intel.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/acpi.h>
#include <linux/clk.h>
#include <linux/clkdev.h>
#include <linux/clk-provider.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/platform_device.h>
#include <linux/platform_data/clk-lpss.h>
ACPI / LPSS: Add support for exposing LTR registers to user space Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have registers providing access to LTR (Latency Tolerance Reporting) functionality that allows software to monitor and possibly influence the aggressiveness of the platform's active-state power management. For each LPSS device, there are two modes of operation related to LTR, the auto mode and the software mode. In the auto mode the LTR is set up by the platform firmware and managed by hardware. Software can only read the LTR register values to monitor the platform's behavior. In the software mode it is possible to use LTR to control the extent to which the platform will use its built-in power management features. This changeset adds support for reading the LPSS devices' LTR registers and exposing their values to user space for monitoring and diagnostics purposes. It re-uses the MMIO mappings created to access the LPSS devices' clock registers for reading the values of the LTR registers and exposes them to user space through sysfs device attributes. Namely, a new atrribute group, lpss_ltr, is created for each LPSS device. It contains three new attributes: ltr_mode, auto_ltr, sw_ltr. The value of the ltr_mode attribute reflects the LTR mode being used at the moment (software vs auto) and the other two contain the actual register values (raw) whose meaning depends on the LTR mode. All of these attributes are read-only. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-03-07 06:46:28 +08:00
#include <linux/pm_runtime.h>
#include <linux/delay.h>
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org>
2013-03-07 06:46:20 +08:00
#include "internal.h"
ACPI_MODULE_NAME("acpi_lpss");
#ifdef CONFIG_X86_INTEL_LPSS
#define LPSS_ADDR(desc) ((unsigned long)&desc)
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org>
2013-03-07 06:46:20 +08:00
#define LPSS_CLK_SIZE 0x04
ACPI / LPSS: Add support for exposing LTR registers to user space Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have registers providing access to LTR (Latency Tolerance Reporting) functionality that allows software to monitor and possibly influence the aggressiveness of the platform's active-state power management. For each LPSS device, there are two modes of operation related to LTR, the auto mode and the software mode. In the auto mode the LTR is set up by the platform firmware and managed by hardware. Software can only read the LTR register values to monitor the platform's behavior. In the software mode it is possible to use LTR to control the extent to which the platform will use its built-in power management features. This changeset adds support for reading the LPSS devices' LTR registers and exposing their values to user space for monitoring and diagnostics purposes. It re-uses the MMIO mappings created to access the LPSS devices' clock registers for reading the values of the LTR registers and exposes them to user space through sysfs device attributes. Namely, a new atrribute group, lpss_ltr, is created for each LPSS device. It contains three new attributes: ltr_mode, auto_ltr, sw_ltr. The value of the ltr_mode attribute reflects the LTR mode being used at the moment (software vs auto) and the other two contain the actual register values (raw) whose meaning depends on the LTR mode. All of these attributes are read-only. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-03-07 06:46:28 +08:00
#define LPSS_LTR_SIZE 0x18
/* Offsets relative to LPSS_PRIVATE_OFFSET */
#define LPSS_CLK_DIVIDER_DEF_MASK (BIT(1) | BIT(16))
#define LPSS_RESETS 0x04
#define LPSS_RESETS_RESET_FUNC BIT(0)
#define LPSS_RESETS_RESET_APB BIT(1)
ACPI / LPSS: Add support for exposing LTR registers to user space Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have registers providing access to LTR (Latency Tolerance Reporting) functionality that allows software to monitor and possibly influence the aggressiveness of the platform's active-state power management. For each LPSS device, there are two modes of operation related to LTR, the auto mode and the software mode. In the auto mode the LTR is set up by the platform firmware and managed by hardware. Software can only read the LTR register values to monitor the platform's behavior. In the software mode it is possible to use LTR to control the extent to which the platform will use its built-in power management features. This changeset adds support for reading the LPSS devices' LTR registers and exposing their values to user space for monitoring and diagnostics purposes. It re-uses the MMIO mappings created to access the LPSS devices' clock registers for reading the values of the LTR registers and exposes them to user space through sysfs device attributes. Namely, a new atrribute group, lpss_ltr, is created for each LPSS device. It contains three new attributes: ltr_mode, auto_ltr, sw_ltr. The value of the ltr_mode attribute reflects the LTR mode being used at the moment (software vs auto) and the other two contain the actual register values (raw) whose meaning depends on the LTR mode. All of these attributes are read-only. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-03-07 06:46:28 +08:00
#define LPSS_GENERAL 0x08
#define LPSS_GENERAL_LTR_MODE_SW BIT(2)
#define LPSS_GENERAL_UART_RTS_OVRD BIT(3)
ACPI / LPSS: Add support for exposing LTR registers to user space Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have registers providing access to LTR (Latency Tolerance Reporting) functionality that allows software to monitor and possibly influence the aggressiveness of the platform's active-state power management. For each LPSS device, there are two modes of operation related to LTR, the auto mode and the software mode. In the auto mode the LTR is set up by the platform firmware and managed by hardware. Software can only read the LTR register values to monitor the platform's behavior. In the software mode it is possible to use LTR to control the extent to which the platform will use its built-in power management features. This changeset adds support for reading the LPSS devices' LTR registers and exposing their values to user space for monitoring and diagnostics purposes. It re-uses the MMIO mappings created to access the LPSS devices' clock registers for reading the values of the LTR registers and exposes them to user space through sysfs device attributes. Namely, a new atrribute group, lpss_ltr, is created for each LPSS device. It contains three new attributes: ltr_mode, auto_ltr, sw_ltr. The value of the ltr_mode attribute reflects the LTR mode being used at the moment (software vs auto) and the other two contain the actual register values (raw) whose meaning depends on the LTR mode. All of these attributes are read-only. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-03-07 06:46:28 +08:00
#define LPSS_SW_LTR 0x10
#define LPSS_AUTO_LTR 0x14
#define LPSS_LTR_SNOOP_REQ BIT(15)
#define LPSS_LTR_SNOOP_MASK 0x0000FFFF
#define LPSS_LTR_SNOOP_LAT_1US 0x800
#define LPSS_LTR_SNOOP_LAT_32US 0xC00
#define LPSS_LTR_SNOOP_LAT_SHIFT 5
#define LPSS_LTR_SNOOP_LAT_CUTOFF 3000
#define LPSS_LTR_MAX_VAL 0x3FF
#define LPSS_TX_INT 0x20
#define LPSS_TX_INT_MASK BIT(1)
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org>
2013-03-07 06:46:20 +08:00
#define LPSS_PRV_REG_COUNT 9
/* LPSS Flags */
#define LPSS_CLK BIT(0)
#define LPSS_CLK_GATE BIT(1)
#define LPSS_CLK_DIVIDER BIT(2)
#define LPSS_LTR BIT(3)
#define LPSS_SAVE_CTX BIT(4)
struct lpss_private_data;
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org>
2013-03-07 06:46:20 +08:00
struct lpss_device_desc {
unsigned int flags;
ACPI / LPSS: Add support for exposing LTR registers to user space Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have registers providing access to LTR (Latency Tolerance Reporting) functionality that allows software to monitor and possibly influence the aggressiveness of the platform's active-state power management. For each LPSS device, there are two modes of operation related to LTR, the auto mode and the software mode. In the auto mode the LTR is set up by the platform firmware and managed by hardware. Software can only read the LTR register values to monitor the platform's behavior. In the software mode it is possible to use LTR to control the extent to which the platform will use its built-in power management features. This changeset adds support for reading the LPSS devices' LTR registers and exposing their values to user space for monitoring and diagnostics purposes. It re-uses the MMIO mappings created to access the LPSS devices' clock registers for reading the values of the LTR registers and exposes them to user space through sysfs device attributes. Namely, a new atrribute group, lpss_ltr, is created for each LPSS device. It contains three new attributes: ltr_mode, auto_ltr, sw_ltr. The value of the ltr_mode attribute reflects the LTR mode being used at the moment (software vs auto) and the other two contain the actual register values (raw) whose meaning depends on the LTR mode. All of these attributes are read-only. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-03-07 06:46:28 +08:00
unsigned int prv_offset;
size_t prv_size_override;
void (*setup)(struct lpss_private_data *pdata);
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org>
2013-03-07 06:46:20 +08:00
};
static struct lpss_device_desc lpss_dma_desc = {
.flags = LPSS_CLK,
};
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org>
2013-03-07 06:46:20 +08:00
struct lpss_private_data {
void __iomem *mmio_base;
resource_size_t mmio_size;
unsigned int fixed_clk_rate;
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org>
2013-03-07 06:46:20 +08:00
struct clk *clk;
const struct lpss_device_desc *dev_desc;
u32 prv_reg_ctx[LPSS_PRV_REG_COUNT];
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org>
2013-03-07 06:46:20 +08:00
};
/* UART Component Parameter Register */
#define LPSS_UART_CPR 0xF4
#define LPSS_UART_CPR_AFCE BIT(4)
static void lpss_uart_setup(struct lpss_private_data *pdata)
{
unsigned int offset;
u32 val;
offset = pdata->dev_desc->prv_offset + LPSS_TX_INT;
val = readl(pdata->mmio_base + offset);
writel(val | LPSS_TX_INT_MASK, pdata->mmio_base + offset);
val = readl(pdata->mmio_base + LPSS_UART_CPR);
if (!(val & LPSS_UART_CPR_AFCE)) {
offset = pdata->dev_desc->prv_offset + LPSS_GENERAL;
val = readl(pdata->mmio_base + offset);
val |= LPSS_GENERAL_UART_RTS_OVRD;
writel(val, pdata->mmio_base + offset);
}
}
#define LPSS_I2C_ENABLE 0x6c
static void byt_i2c_setup(struct lpss_private_data *pdata)
{
unsigned int offset;
u32 val;
offset = pdata->dev_desc->prv_offset + LPSS_RESETS;
val = readl(pdata->mmio_base + offset);
val |= LPSS_RESETS_RESET_APB | LPSS_RESETS_RESET_FUNC;
writel(val, pdata->mmio_base + offset);
if (readl(pdata->mmio_base + pdata->dev_desc->prv_offset))
pdata->fixed_clk_rate = 133000000;
writel(0, pdata->mmio_base + LPSS_I2C_ENABLE);
}
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org>
2013-03-07 06:46:20 +08:00
static struct lpss_device_desc lpt_dev_desc = {
.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_LTR,
.prv_offset = 0x800,
};
static struct lpss_device_desc lpt_i2c_dev_desc = {
.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_LTR,
ACPI / LPSS: Add support for exposing LTR registers to user space Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have registers providing access to LTR (Latency Tolerance Reporting) functionality that allows software to monitor and possibly influence the aggressiveness of the platform's active-state power management. For each LPSS device, there are two modes of operation related to LTR, the auto mode and the software mode. In the auto mode the LTR is set up by the platform firmware and managed by hardware. Software can only read the LTR register values to monitor the platform's behavior. In the software mode it is possible to use LTR to control the extent to which the platform will use its built-in power management features. This changeset adds support for reading the LPSS devices' LTR registers and exposing their values to user space for monitoring and diagnostics purposes. It re-uses the MMIO mappings created to access the LPSS devices' clock registers for reading the values of the LTR registers and exposes them to user space through sysfs device attributes. Namely, a new atrribute group, lpss_ltr, is created for each LPSS device. It contains three new attributes: ltr_mode, auto_ltr, sw_ltr. The value of the ltr_mode attribute reflects the LTR mode being used at the moment (software vs auto) and the other two contain the actual register values (raw) whose meaning depends on the LTR mode. All of these attributes are read-only. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-03-07 06:46:28 +08:00
.prv_offset = 0x800,
};
static struct lpss_device_desc lpt_uart_dev_desc = {
.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_LTR,
.prv_offset = 0x800,
.setup = lpss_uart_setup,
ACPI / LPSS: Add support for exposing LTR registers to user space Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have registers providing access to LTR (Latency Tolerance Reporting) functionality that allows software to monitor and possibly influence the aggressiveness of the platform's active-state power management. For each LPSS device, there are two modes of operation related to LTR, the auto mode and the software mode. In the auto mode the LTR is set up by the platform firmware and managed by hardware. Software can only read the LTR register values to monitor the platform's behavior. In the software mode it is possible to use LTR to control the extent to which the platform will use its built-in power management features. This changeset adds support for reading the LPSS devices' LTR registers and exposing their values to user space for monitoring and diagnostics purposes. It re-uses the MMIO mappings created to access the LPSS devices' clock registers for reading the values of the LTR registers and exposes them to user space through sysfs device attributes. Namely, a new atrribute group, lpss_ltr, is created for each LPSS device. It contains three new attributes: ltr_mode, auto_ltr, sw_ltr. The value of the ltr_mode attribute reflects the LTR mode being used at the moment (software vs auto) and the other two contain the actual register values (raw) whose meaning depends on the LTR mode. All of these attributes are read-only. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-03-07 06:46:28 +08:00
};
static struct lpss_device_desc lpt_sdio_dev_desc = {
.flags = LPSS_LTR,
ACPI / LPSS: Add support for exposing LTR registers to user space Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have registers providing access to LTR (Latency Tolerance Reporting) functionality that allows software to monitor and possibly influence the aggressiveness of the platform's active-state power management. For each LPSS device, there are two modes of operation related to LTR, the auto mode and the software mode. In the auto mode the LTR is set up by the platform firmware and managed by hardware. Software can only read the LTR register values to monitor the platform's behavior. In the software mode it is possible to use LTR to control the extent to which the platform will use its built-in power management features. This changeset adds support for reading the LPSS devices' LTR registers and exposing their values to user space for monitoring and diagnostics purposes. It re-uses the MMIO mappings created to access the LPSS devices' clock registers for reading the values of the LTR registers and exposes them to user space through sysfs device attributes. Namely, a new atrribute group, lpss_ltr, is created for each LPSS device. It contains three new attributes: ltr_mode, auto_ltr, sw_ltr. The value of the ltr_mode attribute reflects the LTR mode being used at the moment (software vs auto) and the other two contain the actual register values (raw) whose meaning depends on the LTR mode. All of these attributes are read-only. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-03-07 06:46:28 +08:00
.prv_offset = 0x1000,
.prv_size_override = 0x1018,
};
static struct lpss_device_desc byt_pwm_dev_desc = {
.flags = LPSS_SAVE_CTX,
};
static struct lpss_device_desc byt_uart_dev_desc = {
.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX,
.prv_offset = 0x800,
.setup = lpss_uart_setup,
};
static struct lpss_device_desc byt_spi_dev_desc = {
.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX,
.prv_offset = 0x400,
};
static struct lpss_device_desc byt_sdio_dev_desc = {
.flags = LPSS_CLK,
};
static struct lpss_device_desc byt_i2c_dev_desc = {
.flags = LPSS_CLK | LPSS_SAVE_CTX,
.prv_offset = 0x800,
.setup = byt_i2c_setup,
};
#else
#define LPSS_ADDR(desc) (0UL)
#endif /* CONFIG_X86_INTEL_LPSS */
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org>
2013-03-07 06:46:20 +08:00
static const struct acpi_device_id acpi_lpss_device_ids[] = {
/* Generic LPSS devices */
{ "INTL9C60", LPSS_ADDR(lpss_dma_desc) },
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org>
2013-03-07 06:46:20 +08:00
/* Lynxpoint LPSS devices */
{ "INT33C0", LPSS_ADDR(lpt_dev_desc) },
{ "INT33C1", LPSS_ADDR(lpt_dev_desc) },
{ "INT33C2", LPSS_ADDR(lpt_i2c_dev_desc) },
{ "INT33C3", LPSS_ADDR(lpt_i2c_dev_desc) },
{ "INT33C4", LPSS_ADDR(lpt_uart_dev_desc) },
{ "INT33C5", LPSS_ADDR(lpt_uart_dev_desc) },
{ "INT33C6", LPSS_ADDR(lpt_sdio_dev_desc) },
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org>
2013-03-07 06:46:20 +08:00
{ "INT33C7", },
/* BayTrail LPSS devices */
{ "80860F09", LPSS_ADDR(byt_pwm_dev_desc) },
{ "80860F0A", LPSS_ADDR(byt_uart_dev_desc) },
{ "80860F0E", LPSS_ADDR(byt_spi_dev_desc) },
{ "80860F14", LPSS_ADDR(byt_sdio_dev_desc) },
{ "80860F41", LPSS_ADDR(byt_i2c_dev_desc) },
{ "INT33B2", },
{ "INT33FC", },
/* Braswell LPSS devices */
{ "80862288", LPSS_ADDR(byt_pwm_dev_desc) },
{ "8086228A", LPSS_ADDR(byt_uart_dev_desc) },
{ "8086228E", LPSS_ADDR(byt_spi_dev_desc) },
{ "808622C1", LPSS_ADDR(byt_i2c_dev_desc) },
{ "INT3430", LPSS_ADDR(lpt_dev_desc) },
{ "INT3431", LPSS_ADDR(lpt_dev_desc) },
{ "INT3432", LPSS_ADDR(lpt_i2c_dev_desc) },
{ "INT3433", LPSS_ADDR(lpt_i2c_dev_desc) },
{ "INT3434", LPSS_ADDR(lpt_uart_dev_desc) },
{ "INT3435", LPSS_ADDR(lpt_uart_dev_desc) },
{ "INT3436", LPSS_ADDR(lpt_sdio_dev_desc) },
{ "INT3437", },
/* Wildcat Point LPSS devices */
{ "INT3438", LPSS_ADDR(lpt_dev_desc) },
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org>
2013-03-07 06:46:20 +08:00
{ }
};
#ifdef CONFIG_X86_INTEL_LPSS
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org>
2013-03-07 06:46:20 +08:00
static int is_memory(struct acpi_resource *res, void *not_used)
{
struct resource r;
return !acpi_dev_resource_memory(res, &r);
}
/* LPSS main clock device. */
static struct platform_device *lpss_clk_dev;
static inline void lpt_register_clock_device(void)
{
lpss_clk_dev = platform_device_register_simple("clk-lpt", -1, NULL, 0);
}
static int register_device_clock(struct acpi_device *adev,
struct lpss_private_data *pdata)
{
const struct lpss_device_desc *dev_desc = pdata->dev_desc;
const char *devname = dev_name(&adev->dev);
struct clk *clk = ERR_PTR(-ENODEV);
struct lpss_clk_data *clk_data;
const char *parent, *clk_name;
void __iomem *prv_base;
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org>
2013-03-07 06:46:20 +08:00
if (!lpss_clk_dev)
lpt_register_clock_device();
clk_data = platform_get_drvdata(lpss_clk_dev);
if (!clk_data)
return -ENODEV;
clk = clk_data->clk;
if (!pdata->mmio_base
ACPI / LPSS: Add support for exposing LTR registers to user space Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have registers providing access to LTR (Latency Tolerance Reporting) functionality that allows software to monitor and possibly influence the aggressiveness of the platform's active-state power management. For each LPSS device, there are two modes of operation related to LTR, the auto mode and the software mode. In the auto mode the LTR is set up by the platform firmware and managed by hardware. Software can only read the LTR register values to monitor the platform's behavior. In the software mode it is possible to use LTR to control the extent to which the platform will use its built-in power management features. This changeset adds support for reading the LPSS devices' LTR registers and exposing their values to user space for monitoring and diagnostics purposes. It re-uses the MMIO mappings created to access the LPSS devices' clock registers for reading the values of the LTR registers and exposes them to user space through sysfs device attributes. Namely, a new atrribute group, lpss_ltr, is created for each LPSS device. It contains three new attributes: ltr_mode, auto_ltr, sw_ltr. The value of the ltr_mode attribute reflects the LTR mode being used at the moment (software vs auto) and the other two contain the actual register values (raw) whose meaning depends on the LTR mode. All of these attributes are read-only. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-03-07 06:46:28 +08:00
|| pdata->mmio_size < dev_desc->prv_offset + LPSS_CLK_SIZE)
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org>
2013-03-07 06:46:20 +08:00
return -ENODATA;
parent = clk_data->name;
prv_base = pdata->mmio_base + dev_desc->prv_offset;
if (pdata->fixed_clk_rate) {
clk = clk_register_fixed_rate(NULL, devname, parent, 0,
pdata->fixed_clk_rate);
goto out;
}
if (dev_desc->flags & LPSS_CLK_GATE) {
clk = clk_register_gate(NULL, devname, parent, 0,
prv_base, 0, 0, NULL);
parent = devname;
}
if (dev_desc->flags & LPSS_CLK_DIVIDER) {
/* Prevent division by zero */
if (!readl(prv_base))
writel(LPSS_CLK_DIVIDER_DEF_MASK, prv_base);
clk_name = kasprintf(GFP_KERNEL, "%s-div", devname);
if (!clk_name)
return -ENOMEM;
clk = clk_register_fractional_divider(NULL, clk_name, parent,
0, prv_base,
1, 15, 16, 15, 0, NULL);
parent = clk_name;
clk_name = kasprintf(GFP_KERNEL, "%s-update", devname);
if (!clk_name) {
kfree(parent);
return -ENOMEM;
}
clk = clk_register_gate(NULL, clk_name, parent,
CLK_SET_RATE_PARENT | CLK_SET_RATE_GATE,
prv_base, 31, 0, NULL);
kfree(parent);
kfree(clk_name);
}
out:
if (IS_ERR(clk))
return PTR_ERR(clk);
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org>
2013-03-07 06:46:20 +08:00
pdata->clk = clk;
clk_register_clkdev(clk, NULL, devname);
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org>
2013-03-07 06:46:20 +08:00
return 0;
}
static int acpi_lpss_create_device(struct acpi_device *adev,
const struct acpi_device_id *id)
{
struct lpss_device_desc *dev_desc;
struct lpss_private_data *pdata;
struct resource_list_entry *rentry;
struct list_head resource_list;
struct platform_device *pdev;
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org>
2013-03-07 06:46:20 +08:00
int ret;
dev_desc = (struct lpss_device_desc *)id->driver_data;
if (!dev_desc) {
pdev = acpi_create_platform_device(adev);
return IS_ERR_OR_NULL(pdev) ? PTR_ERR(pdev) : 1;
}
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org>
2013-03-07 06:46:20 +08:00
pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
if (!pdata)
return -ENOMEM;
INIT_LIST_HEAD(&resource_list);
ret = acpi_dev_get_resources(adev, &resource_list, is_memory, NULL);
if (ret < 0)
goto err_out;
list_for_each_entry(rentry, &resource_list, node)
if (resource_type(&rentry->res) == IORESOURCE_MEM) {
if (dev_desc->prv_size_override)
pdata->mmio_size = dev_desc->prv_size_override;
else
pdata->mmio_size = resource_size(&rentry->res);
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org>
2013-03-07 06:46:20 +08:00
pdata->mmio_base = ioremap(rentry->res.start,
pdata->mmio_size);
if (!pdata->mmio_base)
goto err_out;
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org>
2013-03-07 06:46:20 +08:00
break;
}
acpi_dev_free_resource_list(&resource_list);
pdata->dev_desc = dev_desc;
if (dev_desc->setup)
dev_desc->setup(pdata);
if (dev_desc->flags & LPSS_CLK) {
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org>
2013-03-07 06:46:20 +08:00
ret = register_device_clock(adev, pdata);
if (ret) {
/* Skip the device, but continue the namespace scan. */
ret = 0;
goto err_out;
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org>
2013-03-07 06:46:20 +08:00
}
}
/*
* This works around a known issue in ACPI tables where LPSS devices
* have _PS0 and _PS3 without _PSC (and no power resources), so
* acpi_bus_init_power() will assume that the BIOS has put them into D0.
*/
ret = acpi_device_fix_up_power(adev);
if (ret) {
/* Skip the device, but continue the namespace scan. */
ret = 0;
goto err_out;
}
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org>
2013-03-07 06:46:20 +08:00
adev->driver_data = pdata;
pdev = acpi_create_platform_device(adev);
if (!IS_ERR_OR_NULL(pdev)) {
return 1;
}
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org>
2013-03-07 06:46:20 +08:00
ret = PTR_ERR(pdev);
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org>
2013-03-07 06:46:20 +08:00
adev->driver_data = NULL;
err_out:
kfree(pdata);
return ret;
}
static u32 __lpss_reg_read(struct lpss_private_data *pdata, unsigned int reg)
{
return readl(pdata->mmio_base + pdata->dev_desc->prv_offset + reg);
}
static void __lpss_reg_write(u32 val, struct lpss_private_data *pdata,
unsigned int reg)
{
writel(val, pdata->mmio_base + pdata->dev_desc->prv_offset + reg);
}
ACPI / LPSS: Add support for exposing LTR registers to user space Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have registers providing access to LTR (Latency Tolerance Reporting) functionality that allows software to monitor and possibly influence the aggressiveness of the platform's active-state power management. For each LPSS device, there are two modes of operation related to LTR, the auto mode and the software mode. In the auto mode the LTR is set up by the platform firmware and managed by hardware. Software can only read the LTR register values to monitor the platform's behavior. In the software mode it is possible to use LTR to control the extent to which the platform will use its built-in power management features. This changeset adds support for reading the LPSS devices' LTR registers and exposing their values to user space for monitoring and diagnostics purposes. It re-uses the MMIO mappings created to access the LPSS devices' clock registers for reading the values of the LTR registers and exposes them to user space through sysfs device attributes. Namely, a new atrribute group, lpss_ltr, is created for each LPSS device. It contains three new attributes: ltr_mode, auto_ltr, sw_ltr. The value of the ltr_mode attribute reflects the LTR mode being used at the moment (software vs auto) and the other two contain the actual register values (raw) whose meaning depends on the LTR mode. All of these attributes are read-only. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-03-07 06:46:28 +08:00
static int lpss_reg_read(struct device *dev, unsigned int reg, u32 *val)
{
struct acpi_device *adev;
struct lpss_private_data *pdata;
unsigned long flags;
int ret;
ret = acpi_bus_get_device(ACPI_HANDLE(dev), &adev);
if (WARN_ON(ret))
return ret;
spin_lock_irqsave(&dev->power.lock, flags);
if (pm_runtime_suspended(dev)) {
ret = -EAGAIN;
goto out;
}
pdata = acpi_driver_data(adev);
if (WARN_ON(!pdata || !pdata->mmio_base)) {
ret = -ENODEV;
goto out;
}
*val = __lpss_reg_read(pdata, reg);
ACPI / LPSS: Add support for exposing LTR registers to user space Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have registers providing access to LTR (Latency Tolerance Reporting) functionality that allows software to monitor and possibly influence the aggressiveness of the platform's active-state power management. For each LPSS device, there are two modes of operation related to LTR, the auto mode and the software mode. In the auto mode the LTR is set up by the platform firmware and managed by hardware. Software can only read the LTR register values to monitor the platform's behavior. In the software mode it is possible to use LTR to control the extent to which the platform will use its built-in power management features. This changeset adds support for reading the LPSS devices' LTR registers and exposing their values to user space for monitoring and diagnostics purposes. It re-uses the MMIO mappings created to access the LPSS devices' clock registers for reading the values of the LTR registers and exposes them to user space through sysfs device attributes. Namely, a new atrribute group, lpss_ltr, is created for each LPSS device. It contains three new attributes: ltr_mode, auto_ltr, sw_ltr. The value of the ltr_mode attribute reflects the LTR mode being used at the moment (software vs auto) and the other two contain the actual register values (raw) whose meaning depends on the LTR mode. All of these attributes are read-only. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-03-07 06:46:28 +08:00
out:
spin_unlock_irqrestore(&dev->power.lock, flags);
return ret;
}
static ssize_t lpss_ltr_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
u32 ltr_value = 0;
unsigned int reg;
int ret;
reg = strcmp(attr->attr.name, "auto_ltr") ? LPSS_SW_LTR : LPSS_AUTO_LTR;
ret = lpss_reg_read(dev, reg, &ltr_value);
if (ret)
return ret;
return snprintf(buf, PAGE_SIZE, "%08x\n", ltr_value);
}
static ssize_t lpss_ltr_mode_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
u32 ltr_mode = 0;
char *outstr;
int ret;
ret = lpss_reg_read(dev, LPSS_GENERAL, &ltr_mode);
if (ret)
return ret;
outstr = (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) ? "sw" : "auto";
return sprintf(buf, "%s\n", outstr);
}
static DEVICE_ATTR(auto_ltr, S_IRUSR, lpss_ltr_show, NULL);
static DEVICE_ATTR(sw_ltr, S_IRUSR, lpss_ltr_show, NULL);
static DEVICE_ATTR(ltr_mode, S_IRUSR, lpss_ltr_mode_show, NULL);
static struct attribute *lpss_attrs[] = {
&dev_attr_auto_ltr.attr,
&dev_attr_sw_ltr.attr,
&dev_attr_ltr_mode.attr,
NULL,
};
static struct attribute_group lpss_attr_group = {
.attrs = lpss_attrs,
.name = "lpss_ltr",
};
static void acpi_lpss_set_ltr(struct device *dev, s32 val)
{
struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
u32 ltr_mode, ltr_val;
ltr_mode = __lpss_reg_read(pdata, LPSS_GENERAL);
if (val < 0) {
if (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) {
ltr_mode &= ~LPSS_GENERAL_LTR_MODE_SW;
__lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL);
}
return;
}
ltr_val = __lpss_reg_read(pdata, LPSS_SW_LTR) & ~LPSS_LTR_SNOOP_MASK;
if (val >= LPSS_LTR_SNOOP_LAT_CUTOFF) {
ltr_val |= LPSS_LTR_SNOOP_LAT_32US;
val = LPSS_LTR_MAX_VAL;
} else if (val > LPSS_LTR_MAX_VAL) {
ltr_val |= LPSS_LTR_SNOOP_LAT_32US | LPSS_LTR_SNOOP_REQ;
val >>= LPSS_LTR_SNOOP_LAT_SHIFT;
} else {
ltr_val |= LPSS_LTR_SNOOP_LAT_1US | LPSS_LTR_SNOOP_REQ;
}
ltr_val |= val;
__lpss_reg_write(ltr_val, pdata, LPSS_SW_LTR);
if (!(ltr_mode & LPSS_GENERAL_LTR_MODE_SW)) {
ltr_mode |= LPSS_GENERAL_LTR_MODE_SW;
__lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL);
}
}
#ifdef CONFIG_PM
/**
* acpi_lpss_save_ctx() - Save the private registers of LPSS device
* @dev: LPSS device
* @pdata: pointer to the private data of the LPSS device
*
* Most LPSS devices have private registers which may loose their context when
* the device is powered down. acpi_lpss_save_ctx() saves those registers into
* prv_reg_ctx array.
*/
static void acpi_lpss_save_ctx(struct device *dev,
struct lpss_private_data *pdata)
{
unsigned int i;
for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {
unsigned long offset = i * sizeof(u32);
pdata->prv_reg_ctx[i] = __lpss_reg_read(pdata, offset);
dev_dbg(dev, "saving 0x%08x from LPSS reg at offset 0x%02lx\n",
pdata->prv_reg_ctx[i], offset);
}
}
/**
* acpi_lpss_restore_ctx() - Restore the private registers of LPSS device
* @dev: LPSS device
* @pdata: pointer to the private data of the LPSS device
*
* Restores the registers that were previously stored with acpi_lpss_save_ctx().
*/
static void acpi_lpss_restore_ctx(struct device *dev,
struct lpss_private_data *pdata)
{
unsigned int i;
/*
* The following delay is needed or the subsequent write operations may
* fail. The LPSS devices are actually PCI devices and the PCI spec
* expects 10ms delay before the device can be accessed after D3 to D0
* transition.
*/
msleep(10);
for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {
unsigned long offset = i * sizeof(u32);
__lpss_reg_write(pdata->prv_reg_ctx[i], pdata, offset);
dev_dbg(dev, "restoring 0x%08x to LPSS reg at offset 0x%02lx\n",
pdata->prv_reg_ctx[i], offset);
}
}
#ifdef CONFIG_PM_SLEEP
static int acpi_lpss_suspend_late(struct device *dev)
{
struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
int ret;
ret = pm_generic_suspend_late(dev);
if (ret)
return ret;
if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
acpi_lpss_save_ctx(dev, pdata);
return acpi_dev_suspend_late(dev);
}
static int acpi_lpss_resume_early(struct device *dev)
{
struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
int ret;
ret = acpi_dev_resume_early(dev);
if (ret)
return ret;
if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
acpi_lpss_restore_ctx(dev, pdata);
return pm_generic_resume_early(dev);
}
#endif /* CONFIG_PM_SLEEP */
static int acpi_lpss_runtime_suspend(struct device *dev)
{
struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
int ret;
ret = pm_generic_runtime_suspend(dev);
if (ret)
return ret;
if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
acpi_lpss_save_ctx(dev, pdata);
return acpi_dev_runtime_suspend(dev);
}
static int acpi_lpss_runtime_resume(struct device *dev)
{
struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
int ret;
ret = acpi_dev_runtime_resume(dev);
if (ret)
return ret;
if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
acpi_lpss_restore_ctx(dev, pdata);
return pm_generic_runtime_resume(dev);
}
#endif /* CONFIG_PM */
static struct dev_pm_domain acpi_lpss_pm_domain = {
.ops = {
#ifdef CONFIG_PM
#ifdef CONFIG_PM_SLEEP
.prepare = acpi_subsys_prepare,
.complete = acpi_subsys_complete,
.suspend = acpi_subsys_suspend,
.suspend_late = acpi_lpss_suspend_late,
.resume_early = acpi_lpss_resume_early,
.freeze = acpi_subsys_freeze,
.poweroff = acpi_subsys_suspend,
.poweroff_late = acpi_lpss_suspend_late,
.restore_early = acpi_lpss_resume_early,
#endif
.runtime_suspend = acpi_lpss_runtime_suspend,
.runtime_resume = acpi_lpss_runtime_resume,
#endif
},
};
ACPI / LPSS: Add support for exposing LTR registers to user space Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have registers providing access to LTR (Latency Tolerance Reporting) functionality that allows software to monitor and possibly influence the aggressiveness of the platform's active-state power management. For each LPSS device, there are two modes of operation related to LTR, the auto mode and the software mode. In the auto mode the LTR is set up by the platform firmware and managed by hardware. Software can only read the LTR register values to monitor the platform's behavior. In the software mode it is possible to use LTR to control the extent to which the platform will use its built-in power management features. This changeset adds support for reading the LPSS devices' LTR registers and exposing their values to user space for monitoring and diagnostics purposes. It re-uses the MMIO mappings created to access the LPSS devices' clock registers for reading the values of the LTR registers and exposes them to user space through sysfs device attributes. Namely, a new atrribute group, lpss_ltr, is created for each LPSS device. It contains three new attributes: ltr_mode, auto_ltr, sw_ltr. The value of the ltr_mode attribute reflects the LTR mode being used at the moment (software vs auto) and the other two contain the actual register values (raw) whose meaning depends on the LTR mode. All of these attributes are read-only. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-03-07 06:46:28 +08:00
static int acpi_lpss_platform_notify(struct notifier_block *nb,
unsigned long action, void *data)
{
struct platform_device *pdev = to_platform_device(data);
struct lpss_private_data *pdata;
struct acpi_device *adev;
const struct acpi_device_id *id;
id = acpi_match_device(acpi_lpss_device_ids, &pdev->dev);
if (!id || !id->driver_data)
return 0;
if (acpi_bus_get_device(ACPI_HANDLE(&pdev->dev), &adev))
return 0;
pdata = acpi_driver_data(adev);
if (!pdata)
ACPI / LPSS: Add support for exposing LTR registers to user space Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have registers providing access to LTR (Latency Tolerance Reporting) functionality that allows software to monitor and possibly influence the aggressiveness of the platform's active-state power management. For each LPSS device, there are two modes of operation related to LTR, the auto mode and the software mode. In the auto mode the LTR is set up by the platform firmware and managed by hardware. Software can only read the LTR register values to monitor the platform's behavior. In the software mode it is possible to use LTR to control the extent to which the platform will use its built-in power management features. This changeset adds support for reading the LPSS devices' LTR registers and exposing their values to user space for monitoring and diagnostics purposes. It re-uses the MMIO mappings created to access the LPSS devices' clock registers for reading the values of the LTR registers and exposes them to user space through sysfs device attributes. Namely, a new atrribute group, lpss_ltr, is created for each LPSS device. It contains three new attributes: ltr_mode, auto_ltr, sw_ltr. The value of the ltr_mode attribute reflects the LTR mode being used at the moment (software vs auto) and the other two contain the actual register values (raw) whose meaning depends on the LTR mode. All of these attributes are read-only. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-03-07 06:46:28 +08:00
return 0;
if (pdata->mmio_base &&
pdata->mmio_size < pdata->dev_desc->prv_offset + LPSS_LTR_SIZE) {
ACPI / LPSS: Add support for exposing LTR registers to user space Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have registers providing access to LTR (Latency Tolerance Reporting) functionality that allows software to monitor and possibly influence the aggressiveness of the platform's active-state power management. For each LPSS device, there are two modes of operation related to LTR, the auto mode and the software mode. In the auto mode the LTR is set up by the platform firmware and managed by hardware. Software can only read the LTR register values to monitor the platform's behavior. In the software mode it is possible to use LTR to control the extent to which the platform will use its built-in power management features. This changeset adds support for reading the LPSS devices' LTR registers and exposing their values to user space for monitoring and diagnostics purposes. It re-uses the MMIO mappings created to access the LPSS devices' clock registers for reading the values of the LTR registers and exposes them to user space through sysfs device attributes. Namely, a new atrribute group, lpss_ltr, is created for each LPSS device. It contains three new attributes: ltr_mode, auto_ltr, sw_ltr. The value of the ltr_mode attribute reflects the LTR mode being used at the moment (software vs auto) and the other two contain the actual register values (raw) whose meaning depends on the LTR mode. All of these attributes are read-only. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-03-07 06:46:28 +08:00
dev_err(&pdev->dev, "MMIO size insufficient to access LTR\n");
return 0;
}
switch (action) {
case BUS_NOTIFY_ADD_DEVICE:
pdev->dev.pm_domain = &acpi_lpss_pm_domain;
if (pdata->dev_desc->flags & LPSS_LTR)
return sysfs_create_group(&pdev->dev.kobj,
&lpss_attr_group);
break;
case BUS_NOTIFY_DEL_DEVICE:
if (pdata->dev_desc->flags & LPSS_LTR)
sysfs_remove_group(&pdev->dev.kobj, &lpss_attr_group);
pdev->dev.pm_domain = NULL;
break;
default:
break;
}
ACPI / LPSS: Add support for exposing LTR registers to user space Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have registers providing access to LTR (Latency Tolerance Reporting) functionality that allows software to monitor and possibly influence the aggressiveness of the platform's active-state power management. For each LPSS device, there are two modes of operation related to LTR, the auto mode and the software mode. In the auto mode the LTR is set up by the platform firmware and managed by hardware. Software can only read the LTR register values to monitor the platform's behavior. In the software mode it is possible to use LTR to control the extent to which the platform will use its built-in power management features. This changeset adds support for reading the LPSS devices' LTR registers and exposing their values to user space for monitoring and diagnostics purposes. It re-uses the MMIO mappings created to access the LPSS devices' clock registers for reading the values of the LTR registers and exposes them to user space through sysfs device attributes. Namely, a new atrribute group, lpss_ltr, is created for each LPSS device. It contains three new attributes: ltr_mode, auto_ltr, sw_ltr. The value of the ltr_mode attribute reflects the LTR mode being used at the moment (software vs auto) and the other two contain the actual register values (raw) whose meaning depends on the LTR mode. All of these attributes are read-only. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-03-07 06:46:28 +08:00
return 0;
ACPI / LPSS: Add support for exposing LTR registers to user space Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have registers providing access to LTR (Latency Tolerance Reporting) functionality that allows software to monitor and possibly influence the aggressiveness of the platform's active-state power management. For each LPSS device, there are two modes of operation related to LTR, the auto mode and the software mode. In the auto mode the LTR is set up by the platform firmware and managed by hardware. Software can only read the LTR register values to monitor the platform's behavior. In the software mode it is possible to use LTR to control the extent to which the platform will use its built-in power management features. This changeset adds support for reading the LPSS devices' LTR registers and exposing their values to user space for monitoring and diagnostics purposes. It re-uses the MMIO mappings created to access the LPSS devices' clock registers for reading the values of the LTR registers and exposes them to user space through sysfs device attributes. Namely, a new atrribute group, lpss_ltr, is created for each LPSS device. It contains three new attributes: ltr_mode, auto_ltr, sw_ltr. The value of the ltr_mode attribute reflects the LTR mode being used at the moment (software vs auto) and the other two contain the actual register values (raw) whose meaning depends on the LTR mode. All of these attributes are read-only. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-03-07 06:46:28 +08:00
}
static struct notifier_block acpi_lpss_nb = {
.notifier_call = acpi_lpss_platform_notify,
};
static void acpi_lpss_bind(struct device *dev)
{
struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
if (!pdata || !pdata->mmio_base || !(pdata->dev_desc->flags & LPSS_LTR))
return;
if (pdata->mmio_size >= pdata->dev_desc->prv_offset + LPSS_LTR_SIZE)
dev->power.set_latency_tolerance = acpi_lpss_set_ltr;
else
dev_err(dev, "MMIO size insufficient to access LTR\n");
}
static void acpi_lpss_unbind(struct device *dev)
{
dev->power.set_latency_tolerance = NULL;
}
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org>
2013-03-07 06:46:20 +08:00
static struct acpi_scan_handler lpss_handler = {
.ids = acpi_lpss_device_ids,
.attach = acpi_lpss_create_device,
.bind = acpi_lpss_bind,
.unbind = acpi_lpss_unbind,
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org>
2013-03-07 06:46:20 +08:00
};
void __init acpi_lpss_init(void)
{
ACPI / LPSS: Add support for exposing LTR registers to user space Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have registers providing access to LTR (Latency Tolerance Reporting) functionality that allows software to monitor and possibly influence the aggressiveness of the platform's active-state power management. For each LPSS device, there are two modes of operation related to LTR, the auto mode and the software mode. In the auto mode the LTR is set up by the platform firmware and managed by hardware. Software can only read the LTR register values to monitor the platform's behavior. In the software mode it is possible to use LTR to control the extent to which the platform will use its built-in power management features. This changeset adds support for reading the LPSS devices' LTR registers and exposing their values to user space for monitoring and diagnostics purposes. It re-uses the MMIO mappings created to access the LPSS devices' clock registers for reading the values of the LTR registers and exposes them to user space through sysfs device attributes. Namely, a new atrribute group, lpss_ltr, is created for each LPSS device. It contains three new attributes: ltr_mode, auto_ltr, sw_ltr. The value of the ltr_mode attribute reflects the LTR mode being used at the moment (software vs auto) and the other two contain the actual register values (raw) whose meaning depends on the LTR mode. All of these attributes are read-only. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-03-07 06:46:28 +08:00
if (!lpt_clk_init()) {
bus_register_notifier(&platform_bus_type, &acpi_lpss_nb);
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org>
2013-03-07 06:46:20 +08:00
acpi_scan_add_handler(&lpss_handler);
ACPI / LPSS: Add support for exposing LTR registers to user space Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have registers providing access to LTR (Latency Tolerance Reporting) functionality that allows software to monitor and possibly influence the aggressiveness of the platform's active-state power management. For each LPSS device, there are two modes of operation related to LTR, the auto mode and the software mode. In the auto mode the LTR is set up by the platform firmware and managed by hardware. Software can only read the LTR register values to monitor the platform's behavior. In the software mode it is possible to use LTR to control the extent to which the platform will use its built-in power management features. This changeset adds support for reading the LPSS devices' LTR registers and exposing their values to user space for monitoring and diagnostics purposes. It re-uses the MMIO mappings created to access the LPSS devices' clock registers for reading the values of the LTR registers and exposes them to user space through sysfs device attributes. Namely, a new atrribute group, lpss_ltr, is created for each LPSS device. It contains three new attributes: ltr_mode, auto_ltr, sw_ltr. The value of the ltr_mode attribute reflects the LTR mode being used at the moment (software vs auto) and the other two contain the actual register values (raw) whose meaning depends on the LTR mode. All of these attributes are read-only. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-03-07 06:46:28 +08:00
}
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org>
2013-03-07 06:46:20 +08:00
}
#else
static struct acpi_scan_handler lpss_handler = {
.ids = acpi_lpss_device_ids,
};
void __init acpi_lpss_init(void)
{
acpi_scan_add_handler(&lpss_handler);
}
#endif /* CONFIG_X86_INTEL_LPSS */