- 根目录:
- drivers
- gpio
- gpio-stmpe.c
/*
* Copyright (C) ST-Ericsson SA 2010
*
* License Terms: GNU General Public License, version 2
* Author: Rabin Vincent <rabin.vincent@stericsson.com> for ST-Ericsson
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/gpio.h>
#include <linux/irq.h>
#include <linux/interrupt.h>
#include <linux/mfd/stmpe.h>
/*
* These registers are modified under the irq bus lock and cached to avoid
* unnecessary writes in bus_sync_unlock.
*/
enum { REG_RE, REG_FE, REG_IE };
#define CACHE_NR_REGS 3
#define CACHE_NR_BANKS (STMPE_NR_GPIOS / 8)
struct stmpe_gpio {
struct gpio_chip chip;
struct stmpe *stmpe;
struct device *dev;
struct mutex irq_lock;
int irq_base;
unsigned norequest_mask;
/* Caches of interrupt control registers for bus_lock */
u8 regs[CACHE_NR_REGS][CACHE_NR_BANKS];
u8 oldregs[CACHE_NR_REGS][CACHE_NR_BANKS];
};
static inline struct stmpe_gpio *to_stmpe_gpio(struct gpio_chip *chip)
{
return container_of(chip, struct stmpe_gpio, chip);
}
static int stmpe_gpio_get(struct gpio_chip *chip, unsigned offset)
{
struct stmpe_gpio *stmpe_gpio = to_stmpe_gpio(chip);
struct stmpe *stmpe = stmpe_gpio->stmpe;
u8 reg = stmpe->regs[STMPE_IDX_GPMR_LSB] - (offset / 8);
u8 mask = 1 << (offset % 8);
int ret;
ret = stmpe_reg_read(stmpe, reg);
if (ret < 0)
return ret;
return !!(ret & mask);
}
static void stmpe_gpio_set(struct gpio_chip *chip, unsigned offset, int val)
{
struct stmpe_gpio *stmpe_gpio = to_stmpe_gpio(chip);
struct stmpe *stmpe = stmpe_gpio->stmpe;
int which = val ? STMPE_IDX_GPSR_LSB : STMPE_IDX_GPCR_LSB;
u8 reg = stmpe->regs[which] - (offset / 8);
u8 mask = 1 << (offset % 8);
/*
* Some variants have single register for gpio set/clear functionality.
* For them we need to write 0 to clear and 1 to set.
*/
if (stmpe->regs[STMPE_IDX_GPSR_LSB] == stmpe->regs[STMPE_IDX_GPCR_LSB])
stmpe_set_bits(stmpe, reg, mask, val ? mask : 0);
else
stmpe_reg_write(stmpe, reg, mask);
}
static int stmpe_gpio_direction_output(struct gpio_chip *chip,
unsigned offset, int val)
{
struct stmpe_gpio *stmpe_gpio = to_stmpe_gpio(chip);
struct stmpe *stmpe = stmpe_gpio->stmpe;
u8 reg = stmpe->regs[STMPE_IDX_GPDR_LSB] - (offset / 8);
u8 mask = 1 << (offset % 8);
stmpe_gpio_set(chip, offset, val);
return stmpe_set_bits(stmpe, reg, mask, mask);
}
static int stmpe_gpio_direction_input(struct gpio_chip *chip,
unsigned offset)
{
struct stmpe_gpio *stmpe_gpio = to_stmpe_gpio(chip);
struct stmpe *stmpe = stmpe_gpio->stmpe;
u8 reg = stmpe->regs[STMPE_IDX_GPDR_LSB] - (offset / 8);
u8 mask = 1 << (offset % 8);
return stmpe_set_bits(stmpe, reg, mask, 0);
}
static int stmpe_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
{
struct stmpe_gpio *stmpe_gpio = to_stmpe_gpio(chip);
return stmpe_gpio->irq_base + offset;
}
static int stmpe_gpio_request(struct gpio_chip *chip, unsigned offset)
{
struct stmpe_gpio *stmpe_gpio = to_stmpe_gpio(chip);
struct stmpe *stmpe = stmpe_gpio->stmpe;
if (stmpe_gpio->norequest_mask & (1 << offset))
return -EINVAL;
return stmpe_set_altfunc(stmpe, 1 << offset, STMPE_BLOCK_GPIO);
}
static struct gpio_chip template_chip = {
.label = "stmpe",
.owner = THIS_MODULE,
.direction_input = stmpe_gpio_direction_input,
.get = stmpe_gpio_get,
.direction_output = stmpe_gpio_direction_output,
.set = stmpe_gpio_set,
.to_irq = stmpe_gpio_to_irq,
.request = stmpe_gpio_request,
.can_sleep = 1,
};
static int stmpe_gpio_irq_set_type(struct irq_data *d, unsigned int type)
{
struct stmpe_gpio *stmpe_gpio = irq_data_get_irq_chip_data(d);
int offset = d->irq - stmpe_gpio->irq_base;
int regoffset = offset / 8;
int mask = 1 << (offset % 8);
if (type == IRQ_TYPE_LEVEL_LOW || type == IRQ_TYPE_LEVEL_HIGH)
return -EINVAL;
/* STMPE801 doesn't have RE and FE registers */
if (stmpe_gpio->stmpe->partnum == STMPE801)
return 0;
if (type == IRQ_TYPE_EDGE_RISING)
stmpe_gpio->regs[REG_RE][regoffset] |= mask;
else
stmpe_gpio->regs[REG_RE][regoffset] &= ~mask;
if (type == IRQ_TYPE_EDGE_FALLING)
stmpe_gpio->regs[REG_FE][regoffset] |= mask;
else
stmpe_gpio->regs[REG_FE][regoffset] &= ~mask;
return 0;
}
static void stmpe_gpio_irq_lock(struct irq_data *d)
{
struct stmpe_gpio *stmpe_gpio = irq_data_get_irq_chip_data(d);
mutex_lock(&stmpe_gpio->irq_lock);
}
static void stmpe_gpio_irq_sync_unlock(struct irq_data *d)
{
struct stmpe_gpio *stmpe_gpio = irq_data_get_irq_chip_data(d);
struct stmpe *stmpe = stmpe_gpio->stmpe;
int num_banks = DIV_ROUND_UP(stmpe->num_gpios, 8);
static const u8 regmap[] = {
[REG_RE] = STMPE_IDX_GPRER_LSB,
[REG_FE] = STMPE_IDX_GPFER_LSB,
[REG_IE] = STMPE_IDX_IEGPIOR_LSB,
};
int i, j;
for (i = 0; i < CACHE_NR_REGS; i++) {
/* STMPE801 doesn't have RE and FE registers */
if ((stmpe->partnum == STMPE801) &&
(i != REG_IE))
continue;
for (j = 0; j < num_banks; j++) {
u8 old = stmpe_gpio->oldregs[i][j];
u8 new = stmpe_gpio->regs[i][j];
if (new == old)
continue;
stmpe_gpio->oldregs[i][j] = new;
stmpe_reg_write(stmpe, stmpe->regs[regmap[i]] - j, new);
}
}
mutex_unlock(&stmpe_gpio->irq_lock);
}
static void stmpe_gpio_irq_mask(struct irq_data *d)
{
struct stmpe_gpio *stmpe_gpio = irq_data_get_irq_chip_data(d);
int offset = d->irq - stmpe_gpio->irq_base;
int regoffset = offset / 8;
int mask = 1 << (offset % 8);
stmpe_gpio->regs[REG_IE][regoffset] &= ~mask;
}
static void stmpe_gpio_irq_unmask(struct irq_data *d)
{
struct stmpe_gpio *stmpe_gpio = irq_data_get_irq_chip_data(d);
int offset = d->irq - stmpe_gpio->irq_base;
int regoffset = offset / 8;
int mask = 1 << (offset % 8);
stmpe_gpio->regs[REG_IE][regoffset] |= mask;
}
static struct irq_chip stmpe_gpio_irq_chip = {
.name = "stmpe-gpio",
.irq_bus_lock = stmpe_gpio_irq_lock,
.irq_bus_sync_unlock = stmpe_gpio_irq_sync_unlock,
.irq_mask = stmpe_gpio_irq_mask,
.irq_unmask = stmpe_gpio_irq_unmask,
.irq_set_type = stmpe_gpio_irq_set_type,
};
static irqreturn_t stmpe_gpio_irq(int irq, void *dev)
{
struct stmpe_gpio *stmpe_gpio = dev;
struct stmpe *stmpe = stmpe_gpio->stmpe;
u8 statmsbreg = stmpe->regs[STMPE_IDX_ISGPIOR_MSB];
int num_banks = DIV_ROUND_UP(stmpe->num_gpios, 8);
u8 status[num_banks];
int ret;
int i;
ret = stmpe_block_read(stmpe, statmsbreg, num_banks, status);
if (ret < 0)
return IRQ_NONE;
for (i = 0; i < num_banks; i++) {
int bank = num_banks - i - 1;
unsigned int enabled = stmpe_gpio->regs[REG_IE][bank];
unsigned int stat = status[i];
stat &= enabled;
if (!stat)
continue;
while (stat) {
int bit = __ffs(stat);
int line = bank * 8 + bit;
handle_nested_irq(stmpe_gpio->irq_base + line);
stat &= ~(1 << bit);
}
stmpe_reg_write(stmpe, statmsbreg + i, status[i]);
/* Edge detect register is not present on 801 */
if (stmpe->partnum != STMPE801)
stmpe_reg_write(stmpe, stmpe->regs[STMPE_IDX_GPEDR_MSB]
+ i, status[i]);
}
return IRQ_HANDLED;
}
static int __devinit stmpe_gpio_irq_init(struct stmpe_gpio *stmpe_gpio)
{
int base = stmpe_gpio->irq_base;
int irq;
for (irq = base; irq < base + stmpe_gpio->chip.ngpio; irq++) {
irq_set_chip_data(irq, stmpe_gpio);
irq_set_chip_and_handler(irq, &stmpe_gpio_irq_chip,
handle_simple_irq);
irq_set_nested_thread(irq, 1);
#ifdef CONFIG_ARM
set_irq_flags(irq, IRQF_VALID);
#else
irq_set_noprobe(irq);
#endif
}
return 0;
}
static void stmpe_gpio_irq_remove(struct stmpe_gpio *stmpe_gpio)
{
int base = stmpe_gpio->irq_base;
int irq;
for (irq = base; irq < base + stmpe_gpio->chip.ngpio; irq++) {
#ifdef CONFIG_ARM
set_irq_flags(irq, 0);
#endif
irq_set_chip_and_handler(irq, NULL, NULL);
irq_set_chip_data(irq, NULL);
}
}
static int __devinit stmpe_gpio_probe(struct platform_device *pdev)
{
struct stmpe *stmpe = dev_get_drvdata(pdev->dev.parent);
struct stmpe_gpio_platform_data *pdata;
struct stmpe_gpio *stmpe_gpio;
int ret;
int irq = 0;
pdata = stmpe->pdata->gpio;
irq = platform_get_irq(pdev, 0);
stmpe_gpio = kzalloc(sizeof(struct stmpe_gpio), GFP_KERNEL);
if (!stmpe_gpio)
return -ENOMEM;
mutex_init(&stmpe_gpio->irq_lock);
stmpe_gpio->dev = &pdev->dev;
stmpe_gpio->stmpe = stmpe;
stmpe_gpio->norequest_mask = pdata ? pdata->norequest_mask : 0;
stmpe_gpio->chip = template_chip;
stmpe_gpio->chip.ngpio = stmpe->num_gpios;
stmpe_gpio->chip.dev = &pdev->dev;
stmpe_gpio->chip.base = pdata ? pdata->gpio_base : -1;
if (irq >= 0)
stmpe_gpio->irq_base = stmpe->irq_base + STMPE_INT_GPIO(0);
else
dev_info(&pdev->dev,
"device configured in no-irq mode; "
"irqs are not available\n");
ret = stmpe_enable(stmpe, STMPE_BLOCK_GPIO);
if (ret)
goto out_free;
if (irq >= 0) {
ret = stmpe_gpio_irq_init(stmpe_gpio);
if (ret)
goto out_disable;
ret = request_threaded_irq(irq, NULL, stmpe_gpio_irq,
IRQF_ONESHOT, "stmpe-gpio", stmpe_gpio);
if (ret) {
dev_err(&pdev->dev, "unable to get irq: %d\n", ret);
goto out_removeirq;
}
}
ret = gpiochip_add(&stmpe_gpio->chip);
if (ret) {
dev_err(&pdev->dev, "unable to add gpiochip: %d\n", ret);
goto out_freeirq;
}
if (pdata && pdata->setup)
pdata->setup(stmpe, stmpe_gpio->chip.base);
platform_set_drvdata(pdev, stmpe_gpio);
return 0;
out_freeirq:
if (irq >= 0)
free_irq(irq, stmpe_gpio);
out_removeirq:
if (irq >= 0)
stmpe_gpio_irq_remove(stmpe_gpio);
out_disable:
stmpe_disable(stmpe, STMPE_BLOCK_GPIO);
out_free:
kfree(stmpe_gpio);
return ret;
}
static int __devexit stmpe_gpio_remove(struct platform_device *pdev)
{
struct stmpe_gpio *stmpe_gpio = platform_get_drvdata(pdev);
struct stmpe *stmpe = stmpe_gpio->stmpe;
struct stmpe_gpio_platform_data *pdata = stmpe->pdata->gpio;
int irq = platform_get_irq(pdev, 0);
int ret;
if (pdata && pdata->remove)
pdata->remove(stmpe, stmpe_gpio->chip.base);
ret = gpiochip_remove(&stmpe_gpio->chip);
if (ret < 0) {
dev_err(stmpe_gpio->dev,
"unable to remove gpiochip: %d\n", ret);
return ret;
}
stmpe_disable(stmpe, STMPE_BLOCK_GPIO);
if (irq >= 0) {
free_irq(irq, stmpe_gpio);
stmpe_gpio_irq_remove(stmpe_gpio);
}
platform_set_drvdata(pdev, NULL);
kfree(stmpe_gpio);
return 0;
}
static struct platform_driver stmpe_gpio_driver = {
.driver.name = "stmpe-gpio",
.driver.owner = THIS_MODULE,
.probe = stmpe_gpio_probe,
.remove = __devexit_p(stmpe_gpio_remove),
};
static int __init stmpe_gpio_init(void)
{
return platform_driver_register(&stmpe_gpio_driver);
}
subsys_initcall(stmpe_gpio_init);
static void __exit stmpe_gpio_exit(void)
{
platform_driver_unregister(&stmpe_gpio_driver);
}
module_exit(stmpe_gpio_exit);
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("STMPExxxx GPIO driver");
MODULE_AUTHOR("Rabin Vincent <rabin.vincent@stericsson.com>");