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linux/drivers/i2c/busses/i2c-designware-platdrv.c
Alan Cox 0409516a2d i2c: designware: add new bindings 
This may appear as PCI or ACPI depending upon the firmware so we
have to list both. All share the same ACPI identifier but not
the same PCI identifier.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-08-02 13:19:54 +02:00

308 lines
7.8 KiB
C
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/*
* 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/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 "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);
bool fs_mode = dev->master_cfg & DW_IC_CON_SPEED_FAST;
if (!ACPI_HANDLE(&pdev->dev))
return -ENODEV;
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,
fs_mode ? NULL : &dev->sda_hold_time);
dw_i2c_acpi_params(pdev, "FMCN", &dev->fs_hcnt, &dev->fs_lcnt,
fs_mode ? &dev->sda_hold_time : NULL);
return 0;
}
static const struct acpi_device_id dw_i2c_acpi_match[] = {
{ "INT33C2", 0 },
{ "INT33C3", 0 },
{ "INT3432", 0 },
{ "INT3433", 0 },
{ "80860F41", 0 },
{ "808622C1", 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 dw_i2c_probe(struct platform_device *pdev)
{
struct dw_i2c_dev *dev;
struct i2c_adapter *adap;
struct resource *mem;
int irq, r;
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);
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 (pdev->dev.of_node) {
u32 ht = 0;
u32 ic_clk = dev->get_clk_rate_khz(dev);
of_property_read_u32(pdev->dev.of_node,
"i2c-sda-hold-time-ns", &ht);
dev->sda_hold_time = div_u64((u64)ic_clk * ht + 500000,
1000000);
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);
}
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;
dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE |
DW_IC_CON_RESTART_EN | DW_IC_CON_SPEED_FAST;
/* Try first if we can configure the device from ACPI */
r = dw_i2c_acpi_configure(pdev);
if (r) {
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);
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");
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