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linux/drivers/mfd/tc35892.c
Wolfram Sang fbae3fb154 i2c: Remove all i2c_set_clientdata(client, NULL) in drivers 
I2C drivers can use the clientdata-pointer to point to private data. As I2C
devices are not really unregistered, but merely detached from their driver, it
used to be the drivers obligation to clear this pointer during remove() or a
failed probe(). As a couple of drivers forgot to do this, it was agreed that it
was cleaner if the i2c-core does this clearance when appropriate, as there is
no guarantee for the lifetime of the clientdata-pointer after remove() anyhow.
This feature was added to the core with commit
e4a7b9b04d to fix the faulty drivers.

As there is no need anymore to clear the clientdata-pointer, remove all current
occurrences in the drivers to simplify the code and prevent confusion.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Richard Purdie <rpurdie@linux.intel.com>
Acked-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-06-03 11:33:58 +02:00

345 lines
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/*
* Copyright (C) ST-Ericsson SA 2010
*
* License Terms: GNU General Public License, version 2
* Author: Hanumath Prasad <hanumath.prasad@stericsson.com> for ST-Ericsson
* Author: Rabin Vincent <rabin.vincent@stericsson.com> for ST-Ericsson
*/
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/mfd/core.h>
#include <linux/mfd/tc35892.h>
/**
* tc35892_reg_read() - read a single TC35892 register
* @tc35892: Device to read from
* @reg: Register to read
*/
int tc35892_reg_read(struct tc35892 *tc35892, u8 reg)
{
int ret;
ret = i2c_smbus_read_byte_data(tc35892->i2c, reg);
if (ret < 0)
dev_err(tc35892->dev, "failed to read reg %#x: %d\n",
reg, ret);
return ret;
}
EXPORT_SYMBOL_GPL(tc35892_reg_read);
/**
* tc35892_reg_read() - write a single TC35892 register
* @tc35892: Device to write to
* @reg: Register to read
* @data: Value to write
*/
int tc35892_reg_write(struct tc35892 *tc35892, u8 reg, u8 data)
{
int ret;
ret = i2c_smbus_write_byte_data(tc35892->i2c, reg, data);
if (ret < 0)
dev_err(tc35892->dev, "failed to write reg %#x: %d\n",
reg, ret);
return ret;
}
EXPORT_SYMBOL_GPL(tc35892_reg_write);
/**
* tc35892_block_read() - read multiple TC35892 registers
* @tc35892: Device to read from
* @reg: First register
* @length: Number of registers
* @values: Buffer to write to
*/
int tc35892_block_read(struct tc35892 *tc35892, u8 reg, u8 length, u8 *values)
{
int ret;
ret = i2c_smbus_read_i2c_block_data(tc35892->i2c, reg, length, values);
if (ret < 0)
dev_err(tc35892->dev, "failed to read regs %#x: %d\n",
reg, ret);
return ret;
}
EXPORT_SYMBOL_GPL(tc35892_block_read);
/**
* tc35892_block_write() - write multiple TC35892 registers
* @tc35892: Device to write to
* @reg: First register
* @length: Number of registers
* @values: Values to write
*/
int tc35892_block_write(struct tc35892 *tc35892, u8 reg, u8 length,
const u8 *values)
{
int ret;
ret = i2c_smbus_write_i2c_block_data(tc35892->i2c, reg, length,
values);
if (ret < 0)
dev_err(tc35892->dev, "failed to write regs %#x: %d\n",
reg, ret);
return ret;
}
EXPORT_SYMBOL_GPL(tc35892_block_write);
/**
* tc35892_set_bits() - set the value of a bitfield in a TC35892 register
* @tc35892: Device to write to
* @reg: Register to write
* @mask: Mask of bits to set
* @values: Value to set
*/
int tc35892_set_bits(struct tc35892 *tc35892, u8 reg, u8 mask, u8 val)
{
int ret;
mutex_lock(&tc35892->lock);
ret = tc35892_reg_read(tc35892, reg);
if (ret < 0)
goto out;
ret &= ~mask;
ret |= val;
ret = tc35892_reg_write(tc35892, reg, ret);
out:
mutex_unlock(&tc35892->lock);
return ret;
}
EXPORT_SYMBOL_GPL(tc35892_set_bits);
static struct resource gpio_resources[] = {
{
.start = TC35892_INT_GPIIRQ,
.end = TC35892_INT_GPIIRQ,
.flags = IORESOURCE_IRQ,
},
};
static struct mfd_cell tc35892_devs[] = {
{
.name = "tc35892-gpio",
.num_resources = ARRAY_SIZE(gpio_resources),
.resources = &gpio_resources[0],
},
};
static irqreturn_t tc35892_irq(int irq, void *data)
{
struct tc35892 *tc35892 = data;
int status;
status = tc35892_reg_read(tc35892, TC35892_IRQST);
if (status < 0)
return IRQ_NONE;
while (status) {
int bit = __ffs(status);
handle_nested_irq(tc35892->irq_base + bit);
status &= ~(1 << bit);
}
/*
* A dummy read or write (to any register) appears to be necessary to
* have the last interrupt clear (for example, GPIO IC write) take
* effect.
*/
tc35892_reg_read(tc35892, TC35892_IRQST);
return IRQ_HANDLED;
}
static void tc35892_irq_dummy(unsigned int irq)
{
/* No mask/unmask at this level */
}
static struct irq_chip tc35892_irq_chip = {
.name = "tc35892",
.mask = tc35892_irq_dummy,
.unmask = tc35892_irq_dummy,
};
static int tc35892_irq_init(struct tc35892 *tc35892)
{
int base = tc35892->irq_base;
int irq;
for (irq = base; irq < base + TC35892_NR_INTERNAL_IRQS; irq++) {
set_irq_chip_data(irq, tc35892);
set_irq_chip_and_handler(irq, &tc35892_irq_chip,
handle_edge_irq);
set_irq_nested_thread(irq, 1);
#ifdef CONFIG_ARM
set_irq_flags(irq, IRQF_VALID);
#else
set_irq_noprobe(irq);
#endif
}
return 0;
}
static void tc35892_irq_remove(struct tc35892 *tc35892)
{
int base = tc35892->irq_base;
int irq;
for (irq = base; irq < base + TC35892_NR_INTERNAL_IRQS; irq++) {
#ifdef CONFIG_ARM
set_irq_flags(irq, 0);
#endif
set_irq_chip_and_handler(irq, NULL, NULL);
set_irq_chip_data(irq, NULL);
}
}
static int tc35892_chip_init(struct tc35892 *tc35892)
{
int manf, ver, ret;
manf = tc35892_reg_read(tc35892, TC35892_MANFCODE);
if (manf < 0)
return manf;
ver = tc35892_reg_read(tc35892, TC35892_VERSION);
if (ver < 0)
return ver;
if (manf != TC35892_MANFCODE_MAGIC) {
dev_err(tc35892->dev, "unknown manufacturer: %#x\n", manf);
return -EINVAL;
}
dev_info(tc35892->dev, "manufacturer: %#x, version: %#x\n", manf, ver);
/* Put everything except the IRQ module into reset */
ret = tc35892_reg_write(tc35892, TC35892_RSTCTRL,
TC35892_RSTCTRL_TIMRST
| TC35892_RSTCTRL_ROTRST
| TC35892_RSTCTRL_KBDRST
| TC35892_RSTCTRL_GPIRST);
if (ret < 0)
return ret;
/* Clear the reset interrupt. */
return tc35892_reg_write(tc35892, TC35892_RSTINTCLR, 0x1);
}
static int __devinit tc35892_probe(struct i2c_client *i2c,
const struct i2c_device_id *id)
{
struct tc35892_platform_data *pdata = i2c->dev.platform_data;
struct tc35892 *tc35892;
int ret;
if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_SMBUS_BYTE_DATA
| I2C_FUNC_SMBUS_I2C_BLOCK))
return -EIO;
tc35892 = kzalloc(sizeof(struct tc35892), GFP_KERNEL);
if (!tc35892)
return -ENOMEM;
mutex_init(&tc35892->lock);
tc35892->dev = &i2c->dev;
tc35892->i2c = i2c;
tc35892->pdata = pdata;
tc35892->irq_base = pdata->irq_base;
tc35892->num_gpio = id->driver_data;
i2c_set_clientdata(i2c, tc35892);
ret = tc35892_chip_init(tc35892);
if (ret)
goto out_free;
ret = tc35892_irq_init(tc35892);
if (ret)
goto out_free;
ret = request_threaded_irq(tc35892->i2c->irq, NULL, tc35892_irq,
IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
"tc35892", tc35892);
if (ret) {
dev_err(tc35892->dev, "failed to request IRQ: %d\n", ret);
goto out_removeirq;
}
ret = mfd_add_devices(tc35892->dev, -1, tc35892_devs,
ARRAY_SIZE(tc35892_devs), NULL,
tc35892->irq_base);
if (ret) {
dev_err(tc35892->dev, "failed to add children\n");
goto out_freeirq;
}
return 0;
out_freeirq:
free_irq(tc35892->i2c->irq, tc35892);
out_removeirq:
tc35892_irq_remove(tc35892);
out_free:
kfree(tc35892);
return ret;
}
static int __devexit tc35892_remove(struct i2c_client *client)
{
struct tc35892 *tc35892 = i2c_get_clientdata(client);
mfd_remove_devices(tc35892->dev);
free_irq(tc35892->i2c->irq, tc35892);
tc35892_irq_remove(tc35892);
kfree(tc35892);
return 0;
}
static const struct i2c_device_id tc35892_id[] = {
{ "tc35892", 24 },
{ }
};
MODULE_DEVICE_TABLE(i2c, tc35892_id);
static struct i2c_driver tc35892_driver = {
.driver.name = "tc35892",
.driver.owner = THIS_MODULE,
.probe = tc35892_probe,
.remove = __devexit_p(tc35892_remove),
.id_table = tc35892_id,
};
static int __init tc35892_init(void)
{
return i2c_add_driver(&tc35892_driver);
}
subsys_initcall(tc35892_init);
static void __exit tc35892_exit(void)
{
i2c_del_driver(&tc35892_driver);
}
module_exit(tc35892_exit);
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("TC35892 MFD core driver");
MODULE_AUTHOR("Hanumath Prasad, Rabin Vincent");
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