356 lines
9.2 KiB
C
356 lines
9.2 KiB
C
/*
|
|
* Synopsys DesignWare I2C adapter driver (master only).
|
|
*
|
|
* Based on the TI DAVINCI I2C adapter driver.
|
|
*
|
|
* Copyright (C) 2006 Texas Instruments.
|
|
* Copyright (C) 2007 MontaVista Software Inc.
|
|
* Copyright (C) 2009 Provigent Ltd.
|
|
*
|
|
* ----------------------------------------------------------------------------
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to the Free Software
|
|
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
|
|
* ----------------------------------------------------------------------------
|
|
*
|
|
*/
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/delay.h>
|
|
#include <linux/i2c.h>
|
|
#include <linux/clk.h>
|
|
#include <linux/clk-provider.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/err.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/of.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/pm.h>
|
|
#include <linux/pm_runtime.h>
|
|
#include <linux/io.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/acpi.h>
|
|
#include <linux/platform_data/i2c-designware.h>
|
|
#include "i2c-designware-core.h"
|
|
|
|
static struct i2c_algorithm i2c_dw_algo = {
|
|
.master_xfer = i2c_dw_xfer,
|
|
.functionality = i2c_dw_func,
|
|
};
|
|
static u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev)
|
|
{
|
|
return clk_get_rate(dev->clk)/1000;
|
|
}
|
|
|
|
#ifdef CONFIG_ACPI
|
|
static void dw_i2c_acpi_params(struct platform_device *pdev, char method[],
|
|
u16 *hcnt, u16 *lcnt, u32 *sda_hold)
|
|
{
|
|
struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
|
|
acpi_handle handle = ACPI_HANDLE(&pdev->dev);
|
|
union acpi_object *obj;
|
|
|
|
if (ACPI_FAILURE(acpi_evaluate_object(handle, method, NULL, &buf)))
|
|
return;
|
|
|
|
obj = (union acpi_object *)buf.pointer;
|
|
if (obj->type == ACPI_TYPE_PACKAGE && obj->package.count == 3) {
|
|
const union acpi_object *objs = obj->package.elements;
|
|
|
|
*hcnt = (u16)objs[0].integer.value;
|
|
*lcnt = (u16)objs[1].integer.value;
|
|
if (sda_hold)
|
|
*sda_hold = (u32)objs[2].integer.value;
|
|
}
|
|
|
|
kfree(buf.pointer);
|
|
}
|
|
|
|
static int dw_i2c_acpi_configure(struct platform_device *pdev)
|
|
{
|
|
struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
|
|
const struct acpi_device_id *id;
|
|
|
|
dev->adapter.nr = -1;
|
|
dev->tx_fifo_depth = 32;
|
|
dev->rx_fifo_depth = 32;
|
|
|
|
/*
|
|
* Try to get SDA hold time and *CNT values from an ACPI method if
|
|
* it exists for both supported speed modes.
|
|
*/
|
|
dw_i2c_acpi_params(pdev, "SSCN", &dev->ss_hcnt, &dev->ss_lcnt, NULL);
|
|
dw_i2c_acpi_params(pdev, "FMCN", &dev->fs_hcnt, &dev->fs_lcnt,
|
|
&dev->sda_hold_time);
|
|
|
|
/*
|
|
* Provide a way for Designware I2C host controllers that are not
|
|
* based on Intel LPSS to specify their input clock frequency via
|
|
* id->driver_data.
|
|
*/
|
|
id = acpi_match_device(pdev->dev.driver->acpi_match_table, &pdev->dev);
|
|
if (id && id->driver_data)
|
|
clk_register_fixed_rate(&pdev->dev, dev_name(&pdev->dev), NULL,
|
|
CLK_IS_ROOT, id->driver_data);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void dw_i2c_acpi_unconfigure(struct platform_device *pdev)
|
|
{
|
|
struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
|
|
const struct acpi_device_id *id;
|
|
|
|
id = acpi_match_device(pdev->dev.driver->acpi_match_table, &pdev->dev);
|
|
if (id && id->driver_data)
|
|
clk_unregister(dev->clk);
|
|
}
|
|
|
|
static const struct acpi_device_id dw_i2c_acpi_match[] = {
|
|
{ "INT33C2", 0 },
|
|
{ "INT33C3", 0 },
|
|
{ "INT3432", 0 },
|
|
{ "INT3433", 0 },
|
|
{ "80860F41", 0 },
|
|
{ "808622C1", 0 },
|
|
{ "AMD0010", 133 * 1000 * 1000 },
|
|
{ }
|
|
};
|
|
MODULE_DEVICE_TABLE(acpi, dw_i2c_acpi_match);
|
|
#else
|
|
static inline int dw_i2c_acpi_configure(struct platform_device *pdev)
|
|
{
|
|
return -ENODEV;
|
|
}
|
|
static inline void dw_i2c_acpi_unconfigure(struct platform_device *pdev) { }
|
|
#endif
|
|
|
|
static int dw_i2c_probe(struct platform_device *pdev)
|
|
{
|
|
struct dw_i2c_dev *dev;
|
|
struct i2c_adapter *adap;
|
|
struct resource *mem;
|
|
struct dw_i2c_platform_data *pdata;
|
|
int irq, r;
|
|
u32 clk_freq, ht = 0;
|
|
|
|
irq = platform_get_irq(pdev, 0);
|
|
if (irq < 0) {
|
|
dev_err(&pdev->dev, "no irq resource?\n");
|
|
return irq; /* -ENXIO */
|
|
}
|
|
|
|
dev = devm_kzalloc(&pdev->dev, sizeof(struct dw_i2c_dev), GFP_KERNEL);
|
|
if (!dev)
|
|
return -ENOMEM;
|
|
|
|
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
|
dev->base = devm_ioremap_resource(&pdev->dev, mem);
|
|
if (IS_ERR(dev->base))
|
|
return PTR_ERR(dev->base);
|
|
|
|
init_completion(&dev->cmd_complete);
|
|
mutex_init(&dev->lock);
|
|
dev->dev = &pdev->dev;
|
|
dev->irq = irq;
|
|
platform_set_drvdata(pdev, dev);
|
|
|
|
/* fast mode by default because of legacy reasons */
|
|
clk_freq = 400000;
|
|
|
|
if (ACPI_COMPANION(&pdev->dev)) {
|
|
dw_i2c_acpi_configure(pdev);
|
|
} else if (pdev->dev.of_node) {
|
|
of_property_read_u32(pdev->dev.of_node,
|
|
"i2c-sda-hold-time-ns", &ht);
|
|
|
|
of_property_read_u32(pdev->dev.of_node,
|
|
"i2c-sda-falling-time-ns",
|
|
&dev->sda_falling_time);
|
|
of_property_read_u32(pdev->dev.of_node,
|
|
"i2c-scl-falling-time-ns",
|
|
&dev->scl_falling_time);
|
|
|
|
of_property_read_u32(pdev->dev.of_node, "clock-frequency",
|
|
&clk_freq);
|
|
|
|
/* Only standard mode at 100kHz and fast mode at 400kHz
|
|
* are supported.
|
|
*/
|
|
if (clk_freq != 100000 && clk_freq != 400000) {
|
|
dev_err(&pdev->dev, "Only 100kHz and 400kHz supported");
|
|
return -EINVAL;
|
|
}
|
|
} else {
|
|
pdata = dev_get_platdata(&pdev->dev);
|
|
if (pdata)
|
|
clk_freq = pdata->i2c_scl_freq;
|
|
}
|
|
|
|
dev->functionality =
|
|
I2C_FUNC_I2C |
|
|
I2C_FUNC_10BIT_ADDR |
|
|
I2C_FUNC_SMBUS_BYTE |
|
|
I2C_FUNC_SMBUS_BYTE_DATA |
|
|
I2C_FUNC_SMBUS_WORD_DATA |
|
|
I2C_FUNC_SMBUS_I2C_BLOCK;
|
|
if (clk_freq == 100000)
|
|
dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE |
|
|
DW_IC_CON_RESTART_EN | DW_IC_CON_SPEED_STD;
|
|
else
|
|
dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE |
|
|
DW_IC_CON_RESTART_EN | DW_IC_CON_SPEED_FAST;
|
|
|
|
dev->clk = devm_clk_get(&pdev->dev, NULL);
|
|
dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz;
|
|
if (IS_ERR(dev->clk))
|
|
return PTR_ERR(dev->clk);
|
|
clk_prepare_enable(dev->clk);
|
|
|
|
if (!dev->sda_hold_time && ht) {
|
|
u32 ic_clk = dev->get_clk_rate_khz(dev);
|
|
|
|
dev->sda_hold_time = div_u64((u64)ic_clk * ht + 500000,
|
|
1000000);
|
|
}
|
|
|
|
if (!dev->tx_fifo_depth) {
|
|
u32 param1 = i2c_dw_read_comp_param(dev);
|
|
|
|
dev->tx_fifo_depth = ((param1 >> 16) & 0xff) + 1;
|
|
dev->rx_fifo_depth = ((param1 >> 8) & 0xff) + 1;
|
|
dev->adapter.nr = pdev->id;
|
|
}
|
|
r = i2c_dw_init(dev);
|
|
if (r)
|
|
return r;
|
|
|
|
i2c_dw_disable_int(dev);
|
|
r = devm_request_irq(&pdev->dev, dev->irq, i2c_dw_isr, IRQF_SHARED,
|
|
pdev->name, dev);
|
|
if (r) {
|
|
dev_err(&pdev->dev, "failure requesting irq %i\n", dev->irq);
|
|
return r;
|
|
}
|
|
|
|
adap = &dev->adapter;
|
|
i2c_set_adapdata(adap, dev);
|
|
adap->owner = THIS_MODULE;
|
|
adap->class = I2C_CLASS_DEPRECATED;
|
|
strlcpy(adap->name, "Synopsys DesignWare I2C adapter",
|
|
sizeof(adap->name));
|
|
adap->algo = &i2c_dw_algo;
|
|
adap->dev.parent = &pdev->dev;
|
|
adap->dev.of_node = pdev->dev.of_node;
|
|
|
|
r = i2c_add_numbered_adapter(adap);
|
|
if (r) {
|
|
dev_err(&pdev->dev, "failure adding adapter\n");
|
|
return r;
|
|
}
|
|
|
|
pm_runtime_set_autosuspend_delay(&pdev->dev, 1000);
|
|
pm_runtime_use_autosuspend(&pdev->dev);
|
|
pm_runtime_set_active(&pdev->dev);
|
|
pm_runtime_enable(&pdev->dev);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int dw_i2c_remove(struct platform_device *pdev)
|
|
{
|
|
struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
|
|
|
|
pm_runtime_get_sync(&pdev->dev);
|
|
|
|
i2c_del_adapter(&dev->adapter);
|
|
|
|
i2c_dw_disable(dev);
|
|
|
|
pm_runtime_put(&pdev->dev);
|
|
pm_runtime_disable(&pdev->dev);
|
|
|
|
if (ACPI_COMPANION(&pdev->dev))
|
|
dw_i2c_acpi_unconfigure(pdev);
|
|
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_OF
|
|
static const struct of_device_id dw_i2c_of_match[] = {
|
|
{ .compatible = "snps,designware-i2c", },
|
|
{},
|
|
};
|
|
MODULE_DEVICE_TABLE(of, dw_i2c_of_match);
|
|
#endif
|
|
|
|
#ifdef CONFIG_PM
|
|
static int dw_i2c_suspend(struct device *dev)
|
|
{
|
|
struct platform_device *pdev = to_platform_device(dev);
|
|
struct dw_i2c_dev *i_dev = platform_get_drvdata(pdev);
|
|
|
|
i2c_dw_disable(i_dev);
|
|
clk_disable_unprepare(i_dev->clk);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int dw_i2c_resume(struct device *dev)
|
|
{
|
|
struct platform_device *pdev = to_platform_device(dev);
|
|
struct dw_i2c_dev *i_dev = platform_get_drvdata(pdev);
|
|
|
|
clk_prepare_enable(i_dev->clk);
|
|
i2c_dw_init(i_dev);
|
|
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
static UNIVERSAL_DEV_PM_OPS(dw_i2c_dev_pm_ops, dw_i2c_suspend,
|
|
dw_i2c_resume, NULL);
|
|
|
|
/* work with hotplug and coldplug */
|
|
MODULE_ALIAS("platform:i2c_designware");
|
|
|
|
static struct platform_driver dw_i2c_driver = {
|
|
.probe = dw_i2c_probe,
|
|
.remove = dw_i2c_remove,
|
|
.driver = {
|
|
.name = "i2c_designware",
|
|
.owner = THIS_MODULE,
|
|
.of_match_table = of_match_ptr(dw_i2c_of_match),
|
|
.acpi_match_table = ACPI_PTR(dw_i2c_acpi_match),
|
|
.pm = &dw_i2c_dev_pm_ops,
|
|
},
|
|
};
|
|
|
|
static int __init dw_i2c_init_driver(void)
|
|
{
|
|
return platform_driver_register(&dw_i2c_driver);
|
|
}
|
|
subsys_initcall(dw_i2c_init_driver);
|
|
|
|
static void __exit dw_i2c_exit_driver(void)
|
|
{
|
|
platform_driver_unregister(&dw_i2c_driver);
|
|
}
|
|
module_exit(dw_i2c_exit_driver);
|
|
|
|
MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>");
|
|
MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter");
|
|
MODULE_LICENSE("GPL");
|