/*
* 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");
