linux/drivers/platform/chrome/cros_ec.c

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// SPDX-License-Identifier: GPL-2.0-only
/*
* ChromeOS EC multi-function device
*
* Copyright (C) 2012 Google, Inc
*
* The ChromeOS EC multi function device is used to mux all the requests
* to the EC device for its multiple features: keyboard controller,
* battery charging and regulator control, firmware update.
*/
#include <linux/of_platform.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/module.h>
mfd / platform: cros_ec: Reorganize platform and mfd includes There is a bit of mess between cros-ec mfd includes and platform includes. For example, we have a linux/mfd/cros_ec.h include that exports the interface implemented in platform/chrome/cros_ec_proto.c. Or we have a linux/mfd/cros_ec_commands.h file that is non related to the multifunction device (in the sense that is not exporting any function of the mfd device). This causes crossed includes between mfd and platform/chrome subsystems and makes the code difficult to read, apart from creating 'curious' situations where a platform/chrome driver includes a linux/mfd/cros_ec.h file just to get the exported functions that are implemented in another platform/chrome driver. In order to have a better separation on what the cros-ec multifunction driver does and what the cros-ec core provides move and rework the affected includes doing: - Move cros_ec_commands.h to include/linux/platform_data/cros_ec_commands.h - Get rid of the parts that are implemented in the platform/chrome/cros_ec_proto.c driver from include/linux/mfd/cros_ec.h to a new file include/linux/platform_data/cros_ec_proto.h - Update all the drivers with the new includes, so - Drivers that only need to know about the protocol include - linux/platform_data/cros_ec_proto.h - linux/platform_data/cros_ec_commands.h - Drivers that need to know about the cros-ec mfd device also include - linux/mfd/cros_ec.h Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Mark Brown <broonie@kernel.org> Acked-by: Wolfram Sang <wsa@the-dreams.de> Acked-by: Neil Armstrong <narmstrong@baylibre.com> Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Acked-by: Sebastian Reichel <sebastian.reichel@collabora.com> Acked-by: Chanwoo Choi <cw00.choi@samsung.com> Reviewed-by: Gwendal Grignou <gwendal@chromium.org> Tested-by: Gwendal Grignou <gwendal@chromium.org> Series changes: 3 - Fix dereferencing pointer to incomplete type 'struct cros_ec_dev' (lkp) Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-09-02 17:53:05 +08:00
#include <linux/platform_data/cros_ec_commands.h>
#include <linux/platform_data/cros_ec_proto.h>
#include <linux/suspend.h>
#include <asm/unaligned.h>
#define CROS_EC_DEV_EC_INDEX 0
#define CROS_EC_DEV_PD_INDEX 1
static struct cros_ec_platform ec_p = {
.ec_name = CROS_EC_DEV_NAME,
.cmd_offset = EC_CMD_PASSTHRU_OFFSET(CROS_EC_DEV_EC_INDEX),
};
static struct cros_ec_platform pd_p = {
.ec_name = CROS_EC_DEV_PD_NAME,
.cmd_offset = EC_CMD_PASSTHRU_OFFSET(CROS_EC_DEV_PD_INDEX),
};
static irqreturn_t ec_irq_handler(int irq, void *data)
{
struct cros_ec_device *ec_dev = data;
ec_dev->last_event_time = cros_ec_get_time_ns();
return IRQ_WAKE_THREAD;
}
static irqreturn_t ec_irq_thread(int irq, void *data)
{
struct cros_ec_device *ec_dev = data;
bool wake_event = true;
int ret;
ret = cros_ec_get_next_event(ec_dev, &wake_event);
/*
* Signal only if wake host events or any interrupt if
* cros_ec_get_next_event() returned an error (default value for
* wake_event is true)
*/
if (wake_event && device_may_wakeup(ec_dev->dev))
pm_wakeup_event(ec_dev->dev, 0);
if (ret > 0)
blocking_notifier_call_chain(&ec_dev->event_notifier,
0, ec_dev);
return IRQ_HANDLED;
}
static int cros_ec_sleep_event(struct cros_ec_device *ec_dev, u8 sleep_event)
{
int ret;
struct {
struct cros_ec_command msg;
union {
struct ec_params_host_sleep_event req0;
struct ec_params_host_sleep_event_v1 req1;
struct ec_response_host_sleep_event_v1 resp1;
} u;
} __packed buf;
memset(&buf, 0, sizeof(buf));
if (ec_dev->host_sleep_v1) {
buf.u.req1.sleep_event = sleep_event;
buf.u.req1.suspend_params.sleep_timeout_ms =
EC_HOST_SLEEP_TIMEOUT_DEFAULT;
buf.msg.outsize = sizeof(buf.u.req1);
if ((sleep_event == HOST_SLEEP_EVENT_S3_RESUME) ||
(sleep_event == HOST_SLEEP_EVENT_S0IX_RESUME))
buf.msg.insize = sizeof(buf.u.resp1);
buf.msg.version = 1;
} else {
buf.u.req0.sleep_event = sleep_event;
buf.msg.outsize = sizeof(buf.u.req0);
}
buf.msg.command = EC_CMD_HOST_SLEEP_EVENT;
ret = cros_ec_cmd_xfer(ec_dev, &buf.msg);
/* For now, report failure to transition to S0ix with a warning. */
if (ret >= 0 && ec_dev->host_sleep_v1 &&
(sleep_event == HOST_SLEEP_EVENT_S0IX_RESUME)) {
ec_dev->last_resume_result =
buf.u.resp1.resume_response.sleep_transitions;
WARN_ONCE(buf.u.resp1.resume_response.sleep_transitions &
EC_HOST_RESUME_SLEEP_TIMEOUT,
"EC detected sleep transition timeout. Total slp_s0 transitions: %d",
buf.u.resp1.resume_response.sleep_transitions &
EC_HOST_RESUME_SLEEP_TRANSITIONS_MASK);
}
return ret;
}
/**
* cros_ec_register() - Register a new ChromeOS EC, using the provided info.
* @ec_dev: Device to register.
*
* Before calling this, allocate a pointer to a new device and then fill
* in all the fields up to the --private-- marker.
*
* Return: 0 on success or negative error code.
*/
int cros_ec_register(struct cros_ec_device *ec_dev)
{
struct device *dev = ec_dev->dev;
int err = 0;
BLOCKING_INIT_NOTIFIER_HEAD(&ec_dev->event_notifier);
ec_dev->max_request = sizeof(struct ec_params_hello);
ec_dev->max_response = sizeof(struct ec_response_get_protocol_info);
ec_dev->max_passthru = 0;
ec_dev->din = devm_kzalloc(dev, ec_dev->din_size, GFP_KERNEL);
if (!ec_dev->din)
return -ENOMEM;
ec_dev->dout = devm_kzalloc(dev, ec_dev->dout_size, GFP_KERNEL);
if (!ec_dev->dout)
return -ENOMEM;
mutex_init(&ec_dev->lock);
err = cros_ec_query_all(ec_dev);
if (err) {
dev_err(dev, "Cannot identify the EC: error %d\n", err);
return err;
}
if (ec_dev->irq > 0) {
err = devm_request_threaded_irq(dev, ec_dev->irq,
ec_irq_handler,
ec_irq_thread,
IRQF_TRIGGER_LOW | IRQF_ONESHOT,
"chromeos-ec", ec_dev);
if (err) {
dev_err(dev, "Failed to request IRQ %d: %d",
ec_dev->irq, err);
return err;
}
}
mfd / platform: cros_ec: Handle chained ECs as platform devices An MFD is a device that contains several sub-devices (cells). For instance, the ChromeOS EC fits in this description as usually contains a charger and can have other devices with different functions like a Real-Time Clock, an Audio codec, a Real-Time Clock, ... If you look at the driver, though, we're doing something odd. We have two MFD cros-ec drivers where one of them (cros-ec-core) instantiates another MFD driver as sub-driver (cros-ec-dev), and the latest instantiates the different sub-devices (Real-Time Clock, Audio codec, etc). MFD ------------------------------------------ cros-ec-core |___ mfd-cellA (cros-ec-dev) | |__ mfd-cell0 | |__ mfd-cell1 | |__ ... | |___ mfd-cellB (cros-ec-dev) |__ mfd-cell0 |__ mfd-cell1 |__ ... The problem that was trying to solve is to describe some kind of topology for the case where we have an EC (cros-ec) chained with another EC (cros-pd). Apart from that this extends the bounds of what MFD was designed to do we might be interested on have other kinds of topology that can't be implemented in that way. Let's prepare the code to move the cros-ec-core part from MFD to platform/chrome as this is clearly a platform specific thing non-related to a MFD device. platform/chrome | MFD ------------------------------------------ | cros-ec ________|___ cros-ec-dev | |__ mfd-cell0 | |__ mfd-cell1 | |__ ... | cros-pd ________|___ cros-ec-dev | |__ mfd-cell0 | |__ mfd-cell1 | |__ ... Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Gwendal Grignou <gwendal@chromium.org> Tested-by: Gwendal Grignou <gwendal@chromium.org> Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-09-02 17:53:00 +08:00
/* Register a platform device for the main EC instance */
ec_dev->ec = platform_device_register_data(ec_dev->dev, "cros-ec-dev",
PLATFORM_DEVID_AUTO, &ec_p,
sizeof(struct cros_ec_platform));
if (IS_ERR(ec_dev->ec)) {
dev_err(ec_dev->dev,
"Failed to create CrOS EC platform device\n");
return PTR_ERR(ec_dev->ec);
}
if (ec_dev->max_passthru) {
/*
mfd / platform: cros_ec: Handle chained ECs as platform devices An MFD is a device that contains several sub-devices (cells). For instance, the ChromeOS EC fits in this description as usually contains a charger and can have other devices with different functions like a Real-Time Clock, an Audio codec, a Real-Time Clock, ... If you look at the driver, though, we're doing something odd. We have two MFD cros-ec drivers where one of them (cros-ec-core) instantiates another MFD driver as sub-driver (cros-ec-dev), and the latest instantiates the different sub-devices (Real-Time Clock, Audio codec, etc). MFD ------------------------------------------ cros-ec-core |___ mfd-cellA (cros-ec-dev) | |__ mfd-cell0 | |__ mfd-cell1 | |__ ... | |___ mfd-cellB (cros-ec-dev) |__ mfd-cell0 |__ mfd-cell1 |__ ... The problem that was trying to solve is to describe some kind of topology for the case where we have an EC (cros-ec) chained with another EC (cros-pd). Apart from that this extends the bounds of what MFD was designed to do we might be interested on have other kinds of topology that can't be implemented in that way. Let's prepare the code to move the cros-ec-core part from MFD to platform/chrome as this is clearly a platform specific thing non-related to a MFD device. platform/chrome | MFD ------------------------------------------ | cros-ec ________|___ cros-ec-dev | |__ mfd-cell0 | |__ mfd-cell1 | |__ ... | cros-pd ________|___ cros-ec-dev | |__ mfd-cell0 | |__ mfd-cell1 | |__ ... Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Gwendal Grignou <gwendal@chromium.org> Tested-by: Gwendal Grignou <gwendal@chromium.org> Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-09-02 17:53:00 +08:00
* Register a platform device for the PD behind the main EC.
* We make the following assumptions:
* - behind an EC, we have a pd
* - only one device added.
* - the EC is responsive at init time (it is not true for a
mfd / platform: cros_ec: Handle chained ECs as platform devices An MFD is a device that contains several sub-devices (cells). For instance, the ChromeOS EC fits in this description as usually contains a charger and can have other devices with different functions like a Real-Time Clock, an Audio codec, a Real-Time Clock, ... If you look at the driver, though, we're doing something odd. We have two MFD cros-ec drivers where one of them (cros-ec-core) instantiates another MFD driver as sub-driver (cros-ec-dev), and the latest instantiates the different sub-devices (Real-Time Clock, Audio codec, etc). MFD ------------------------------------------ cros-ec-core |___ mfd-cellA (cros-ec-dev) | |__ mfd-cell0 | |__ mfd-cell1 | |__ ... | |___ mfd-cellB (cros-ec-dev) |__ mfd-cell0 |__ mfd-cell1 |__ ... The problem that was trying to solve is to describe some kind of topology for the case where we have an EC (cros-ec) chained with another EC (cros-pd). Apart from that this extends the bounds of what MFD was designed to do we might be interested on have other kinds of topology that can't be implemented in that way. Let's prepare the code to move the cros-ec-core part from MFD to platform/chrome as this is clearly a platform specific thing non-related to a MFD device. platform/chrome | MFD ------------------------------------------ | cros-ec ________|___ cros-ec-dev | |__ mfd-cell0 | |__ mfd-cell1 | |__ ... | cros-pd ________|___ cros-ec-dev | |__ mfd-cell0 | |__ mfd-cell1 | |__ ... Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Gwendal Grignou <gwendal@chromium.org> Tested-by: Gwendal Grignou <gwendal@chromium.org> Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-09-02 17:53:00 +08:00
* sensor hub).
*/
mfd / platform: cros_ec: Handle chained ECs as platform devices An MFD is a device that contains several sub-devices (cells). For instance, the ChromeOS EC fits in this description as usually contains a charger and can have other devices with different functions like a Real-Time Clock, an Audio codec, a Real-Time Clock, ... If you look at the driver, though, we're doing something odd. We have two MFD cros-ec drivers where one of them (cros-ec-core) instantiates another MFD driver as sub-driver (cros-ec-dev), and the latest instantiates the different sub-devices (Real-Time Clock, Audio codec, etc). MFD ------------------------------------------ cros-ec-core |___ mfd-cellA (cros-ec-dev) | |__ mfd-cell0 | |__ mfd-cell1 | |__ ... | |___ mfd-cellB (cros-ec-dev) |__ mfd-cell0 |__ mfd-cell1 |__ ... The problem that was trying to solve is to describe some kind of topology for the case where we have an EC (cros-ec) chained with another EC (cros-pd). Apart from that this extends the bounds of what MFD was designed to do we might be interested on have other kinds of topology that can't be implemented in that way. Let's prepare the code to move the cros-ec-core part from MFD to platform/chrome as this is clearly a platform specific thing non-related to a MFD device. platform/chrome | MFD ------------------------------------------ | cros-ec ________|___ cros-ec-dev | |__ mfd-cell0 | |__ mfd-cell1 | |__ ... | cros-pd ________|___ cros-ec-dev | |__ mfd-cell0 | |__ mfd-cell1 | |__ ... Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Gwendal Grignou <gwendal@chromium.org> Tested-by: Gwendal Grignou <gwendal@chromium.org> Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-09-02 17:53:00 +08:00
ec_dev->pd = platform_device_register_data(ec_dev->dev,
"cros-ec-dev",
PLATFORM_DEVID_AUTO, &pd_p,
sizeof(struct cros_ec_platform));
if (IS_ERR(ec_dev->pd)) {
dev_err(ec_dev->dev,
"Failed to create CrOS PD platform device\n");
platform_device_unregister(ec_dev->ec);
return PTR_ERR(ec_dev->pd);
}
}
if (IS_ENABLED(CONFIG_OF) && dev->of_node) {
err = devm_of_platform_populate(dev);
if (err) {
mfd / platform: cros_ec: Handle chained ECs as platform devices An MFD is a device that contains several sub-devices (cells). For instance, the ChromeOS EC fits in this description as usually contains a charger and can have other devices with different functions like a Real-Time Clock, an Audio codec, a Real-Time Clock, ... If you look at the driver, though, we're doing something odd. We have two MFD cros-ec drivers where one of them (cros-ec-core) instantiates another MFD driver as sub-driver (cros-ec-dev), and the latest instantiates the different sub-devices (Real-Time Clock, Audio codec, etc). MFD ------------------------------------------ cros-ec-core |___ mfd-cellA (cros-ec-dev) | |__ mfd-cell0 | |__ mfd-cell1 | |__ ... | |___ mfd-cellB (cros-ec-dev) |__ mfd-cell0 |__ mfd-cell1 |__ ... The problem that was trying to solve is to describe some kind of topology for the case where we have an EC (cros-ec) chained with another EC (cros-pd). Apart from that this extends the bounds of what MFD was designed to do we might be interested on have other kinds of topology that can't be implemented in that way. Let's prepare the code to move the cros-ec-core part from MFD to platform/chrome as this is clearly a platform specific thing non-related to a MFD device. platform/chrome | MFD ------------------------------------------ | cros-ec ________|___ cros-ec-dev | |__ mfd-cell0 | |__ mfd-cell1 | |__ ... | cros-pd ________|___ cros-ec-dev | |__ mfd-cell0 | |__ mfd-cell1 | |__ ... Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Gwendal Grignou <gwendal@chromium.org> Tested-by: Gwendal Grignou <gwendal@chromium.org> Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-09-02 17:53:00 +08:00
platform_device_unregister(ec_dev->pd);
platform_device_unregister(ec_dev->ec);
dev_err(dev, "Failed to register sub-devices\n");
return err;
}
}
/*
* Clear sleep event - this will fail harmlessly on platforms that
* don't implement the sleep event host command.
*/
err = cros_ec_sleep_event(ec_dev, 0);
if (err < 0)
dev_dbg(ec_dev->dev, "Error %d clearing sleep event to ec",
err);
dev_info(dev, "Chrome EC device registered\n");
return 0;
}
EXPORT_SYMBOL(cros_ec_register);
/**
* cros_ec_unregister() - Remove a ChromeOS EC.
* @ec_dev: Device to unregister.
*
* Call this to deregister a ChromeOS EC, then clean up any private data.
*
* Return: 0 on success or negative error code.
*/
mfd / platform: cros_ec: Handle chained ECs as platform devices An MFD is a device that contains several sub-devices (cells). For instance, the ChromeOS EC fits in this description as usually contains a charger and can have other devices with different functions like a Real-Time Clock, an Audio codec, a Real-Time Clock, ... If you look at the driver, though, we're doing something odd. We have two MFD cros-ec drivers where one of them (cros-ec-core) instantiates another MFD driver as sub-driver (cros-ec-dev), and the latest instantiates the different sub-devices (Real-Time Clock, Audio codec, etc). MFD ------------------------------------------ cros-ec-core |___ mfd-cellA (cros-ec-dev) | |__ mfd-cell0 | |__ mfd-cell1 | |__ ... | |___ mfd-cellB (cros-ec-dev) |__ mfd-cell0 |__ mfd-cell1 |__ ... The problem that was trying to solve is to describe some kind of topology for the case where we have an EC (cros-ec) chained with another EC (cros-pd). Apart from that this extends the bounds of what MFD was designed to do we might be interested on have other kinds of topology that can't be implemented in that way. Let's prepare the code to move the cros-ec-core part from MFD to platform/chrome as this is clearly a platform specific thing non-related to a MFD device. platform/chrome | MFD ------------------------------------------ | cros-ec ________|___ cros-ec-dev | |__ mfd-cell0 | |__ mfd-cell1 | |__ ... | cros-pd ________|___ cros-ec-dev | |__ mfd-cell0 | |__ mfd-cell1 | |__ ... Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Gwendal Grignou <gwendal@chromium.org> Tested-by: Gwendal Grignou <gwendal@chromium.org> Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-09-02 17:53:00 +08:00
int cros_ec_unregister(struct cros_ec_device *ec_dev)
{
if (ec_dev->pd)
platform_device_unregister(ec_dev->pd);
platform_device_unregister(ec_dev->ec);
return 0;
}
EXPORT_SYMBOL(cros_ec_unregister);
#ifdef CONFIG_PM_SLEEP
/**
* cros_ec_suspend() - Handle a suspend operation for the ChromeOS EC device.
* @ec_dev: Device to suspend.
*
* This can be called by drivers to handle a suspend event.
*
* Return: 0 on success or negative error code.
*/
int cros_ec_suspend(struct cros_ec_device *ec_dev)
{
struct device *dev = ec_dev->dev;
int ret;
u8 sleep_event;
sleep_event = (!IS_ENABLED(CONFIG_ACPI) || pm_suspend_via_firmware()) ?
HOST_SLEEP_EVENT_S3_SUSPEND :
HOST_SLEEP_EVENT_S0IX_SUSPEND;
ret = cros_ec_sleep_event(ec_dev, sleep_event);
if (ret < 0)
dev_dbg(ec_dev->dev, "Error %d sending suspend event to ec",
ret);
if (device_may_wakeup(dev))
ec_dev->wake_enabled = !enable_irq_wake(ec_dev->irq);
disable_irq(ec_dev->irq);
ec_dev->was_wake_device = ec_dev->wake_enabled;
ec_dev->suspended = true;
return 0;
}
EXPORT_SYMBOL(cros_ec_suspend);
static void cros_ec_report_events_during_suspend(struct cros_ec_device *ec_dev)
{
while (ec_dev->mkbp_event_supported &&
cros_ec_get_next_event(ec_dev, NULL) > 0)
blocking_notifier_call_chain(&ec_dev->event_notifier,
1, ec_dev);
}
/**
* cros_ec_resume() - Handle a resume operation for the ChromeOS EC device.
* @ec_dev: Device to resume.
*
* This can be called by drivers to handle a resume event.
*
* Return: 0 on success or negative error code.
*/
int cros_ec_resume(struct cros_ec_device *ec_dev)
{
int ret;
u8 sleep_event;
ec_dev->suspended = false;
enable_irq(ec_dev->irq);
sleep_event = (!IS_ENABLED(CONFIG_ACPI) || pm_suspend_via_firmware()) ?
HOST_SLEEP_EVENT_S3_RESUME :
HOST_SLEEP_EVENT_S0IX_RESUME;
ret = cros_ec_sleep_event(ec_dev, sleep_event);
if (ret < 0)
dev_dbg(ec_dev->dev, "Error %d sending resume event to ec",
ret);
if (ec_dev->wake_enabled) {
disable_irq_wake(ec_dev->irq);
ec_dev->wake_enabled = 0;
}
/*
* Let the mfd devices know about events that occur during
* suspend. This way the clients know what to do with them.
*/
cros_ec_report_events_during_suspend(ec_dev);
return 0;
}
EXPORT_SYMBOL(cros_ec_resume);
#endif
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("ChromeOS EC core driver");