369 строки
9.3 KiB
C
369 строки
9.3 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.
|
|
* ----------------------------------------------------------------------------
|
|
*
|
|
*/
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/delay.h>
|
|
#include <linux/dmi.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/property.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 u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev)
|
|
{
|
|
return clk_get_rate(dev->clk)/1000;
|
|
}
|
|
|
|
#ifdef CONFIG_ACPI
|
|
/*
|
|
* The HCNT/LCNT information coming from ACPI should be the most accurate
|
|
* for given platform. However, some systems get it wrong. On such systems
|
|
* we get better results by calculating those based on the input clock.
|
|
*/
|
|
static const struct dmi_system_id dw_i2c_no_acpi_params[] = {
|
|
{
|
|
.ident = "Dell Inspiron 7348",
|
|
.matches = {
|
|
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
|
|
DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 7348"),
|
|
},
|
|
},
|
|
{ }
|
|
};
|
|
|
|
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 (dmi_check_system(dw_i2c_no_acpi_params))
|
|
return;
|
|
|
|
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);
|
|
|
|
id = acpi_match_device(pdev->dev.driver->acpi_match_table, &pdev->dev);
|
|
if (id && id->driver_data)
|
|
dev->accessor_flags |= (u32)id->driver_data;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct acpi_device_id dw_i2c_acpi_match[] = {
|
|
{ "INT33C2", 0 },
|
|
{ "INT33C3", 0 },
|
|
{ "INT3432", 0 },
|
|
{ "INT3433", 0 },
|
|
{ "80860F41", 0 },
|
|
{ "808622C1", 0 },
|
|
{ "AMD0010", ACCESS_INTR_MASK },
|
|
{ "AMDI0510", 0 },
|
|
{ "APMC0D0F", 0 },
|
|
{ }
|
|
};
|
|
MODULE_DEVICE_TABLE(acpi, dw_i2c_acpi_match);
|
|
#else
|
|
static inline int dw_i2c_acpi_configure(struct platform_device *pdev)
|
|
{
|
|
return -ENODEV;
|
|
}
|
|
#endif
|
|
|
|
static int i2c_dw_plat_prepare_clk(struct dw_i2c_dev *i_dev, bool prepare)
|
|
{
|
|
if (IS_ERR(i_dev->clk))
|
|
return PTR_ERR(i_dev->clk);
|
|
|
|
if (prepare)
|
|
return clk_prepare_enable(i_dev->clk);
|
|
|
|
clk_disable_unprepare(i_dev->clk);
|
|
return 0;
|
|
}
|
|
|
|
static int dw_i2c_plat_probe(struct platform_device *pdev)
|
|
{
|
|
struct dw_i2c_platform_data *pdata = dev_get_platdata(&pdev->dev);
|
|
struct dw_i2c_dev *dev;
|
|
struct i2c_adapter *adap;
|
|
struct resource *mem;
|
|
int irq, r;
|
|
u32 clk_freq, ht = 0;
|
|
|
|
irq = platform_get_irq(pdev, 0);
|
|
if (irq < 0)
|
|
return irq;
|
|
|
|
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);
|
|
|
|
dev->dev = &pdev->dev;
|
|
dev->irq = irq;
|
|
platform_set_drvdata(pdev, dev);
|
|
|
|
/* fast mode by default because of legacy reasons */
|
|
clk_freq = 400000;
|
|
|
|
if (pdata) {
|
|
clk_freq = pdata->i2c_scl_freq;
|
|
} else {
|
|
device_property_read_u32(&pdev->dev, "i2c-sda-hold-time-ns",
|
|
&ht);
|
|
device_property_read_u32(&pdev->dev, "i2c-sda-falling-time-ns",
|
|
&dev->sda_falling_time);
|
|
device_property_read_u32(&pdev->dev, "i2c-scl-falling-time-ns",
|
|
&dev->scl_falling_time);
|
|
device_property_read_u32(&pdev->dev, "clock-frequency",
|
|
&clk_freq);
|
|
}
|
|
|
|
if (has_acpi_companion(&pdev->dev))
|
|
dw_i2c_acpi_configure(pdev);
|
|
|
|
/*
|
|
* 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;
|
|
}
|
|
|
|
r = i2c_dw_eval_lock_support(dev);
|
|
if (r)
|
|
return r;
|
|
|
|
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);
|
|
if (!i2c_dw_plat_prepare_clk(dev, true)) {
|
|
dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz;
|
|
|
|
if (!dev->sda_hold_time && ht)
|
|
dev->sda_hold_time = div_u64(
|
|
(u64)dev->get_clk_rate_khz(dev) * 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;
|
|
}
|
|
|
|
adap = &dev->adapter;
|
|
adap->owner = THIS_MODULE;
|
|
adap->class = I2C_CLASS_DEPRECATED;
|
|
ACPI_COMPANION_SET(&adap->dev, ACPI_COMPANION(&pdev->dev));
|
|
adap->dev.of_node = pdev->dev.of_node;
|
|
|
|
if (dev->pm_runtime_disabled) {
|
|
pm_runtime_forbid(&pdev->dev);
|
|
} else {
|
|
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);
|
|
}
|
|
|
|
r = i2c_dw_probe(dev);
|
|
if (r && !dev->pm_runtime_disabled)
|
|
pm_runtime_disable(&pdev->dev);
|
|
|
|
return r;
|
|
}
|
|
|
|
static int dw_i2c_plat_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_dont_use_autosuspend(&pdev->dev);
|
|
pm_runtime_put_sync(&pdev->dev);
|
|
if (!dev->pm_runtime_disabled)
|
|
pm_runtime_disable(&pdev->dev);
|
|
|
|
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_SLEEP
|
|
static int dw_i2c_plat_prepare(struct device *dev)
|
|
{
|
|
return pm_runtime_suspended(dev);
|
|
}
|
|
|
|
static void dw_i2c_plat_complete(struct device *dev)
|
|
{
|
|
if (dev->power.direct_complete)
|
|
pm_request_resume(dev);
|
|
}
|
|
#else
|
|
#define dw_i2c_plat_prepare NULL
|
|
#define dw_i2c_plat_complete NULL
|
|
#endif
|
|
|
|
#ifdef CONFIG_PM
|
|
static int dw_i2c_plat_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);
|
|
i2c_dw_plat_prepare_clk(i_dev, false);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int dw_i2c_plat_resume(struct device *dev)
|
|
{
|
|
struct platform_device *pdev = to_platform_device(dev);
|
|
struct dw_i2c_dev *i_dev = platform_get_drvdata(pdev);
|
|
|
|
i2c_dw_plat_prepare_clk(i_dev, true);
|
|
|
|
if (!i_dev->pm_runtime_disabled)
|
|
i2c_dw_init(i_dev);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct dev_pm_ops dw_i2c_dev_pm_ops = {
|
|
.prepare = dw_i2c_plat_prepare,
|
|
.complete = dw_i2c_plat_complete,
|
|
SET_SYSTEM_SLEEP_PM_OPS(dw_i2c_plat_suspend, dw_i2c_plat_resume)
|
|
SET_RUNTIME_PM_OPS(dw_i2c_plat_suspend, dw_i2c_plat_resume, NULL)
|
|
};
|
|
|
|
#define DW_I2C_DEV_PMOPS (&dw_i2c_dev_pm_ops)
|
|
#else
|
|
#define DW_I2C_DEV_PMOPS NULL
|
|
#endif
|
|
|
|
/* work with hotplug and coldplug */
|
|
MODULE_ALIAS("platform:i2c_designware");
|
|
|
|
static struct platform_driver dw_i2c_driver = {
|
|
.probe = dw_i2c_plat_probe,
|
|
.remove = dw_i2c_plat_remove,
|
|
.driver = {
|
|
.name = "i2c_designware",
|
|
.of_match_table = of_match_ptr(dw_i2c_of_match),
|
|
.acpi_match_table = ACPI_PTR(dw_i2c_acpi_match),
|
|
.pm = DW_I2C_DEV_PMOPS,
|
|
},
|
|
};
|
|
|
|
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");
|