linux/drivers/gpio/gpio-tc3589x.c

338 lines
8.4 KiB
C

/*
* 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/init.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/gpio.h>
#include <linux/of.h>
#include <linux/interrupt.h>
#include <linux/mfd/tc3589x.h>
/*
* These registers are modified under the irq bus lock and cached to avoid
* unnecessary writes in bus_sync_unlock.
*/
enum { REG_IBE, REG_IEV, REG_IS, REG_IE };
#define CACHE_NR_REGS 4
#define CACHE_NR_BANKS 3
struct tc3589x_gpio {
struct gpio_chip chip;
struct tc3589x *tc3589x;
struct device *dev;
struct mutex irq_lock;
/* 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 tc3589x_gpio *to_tc3589x_gpio(struct gpio_chip *chip)
{
return container_of(chip, struct tc3589x_gpio, chip);
}
static int tc3589x_gpio_get(struct gpio_chip *chip, unsigned offset)
{
struct tc3589x_gpio *tc3589x_gpio = to_tc3589x_gpio(chip);
struct tc3589x *tc3589x = tc3589x_gpio->tc3589x;
u8 reg = TC3589x_GPIODATA0 + (offset / 8) * 2;
u8 mask = 1 << (offset % 8);
int ret;
ret = tc3589x_reg_read(tc3589x, reg);
if (ret < 0)
return ret;
return ret & mask;
}
static void tc3589x_gpio_set(struct gpio_chip *chip, unsigned offset, int val)
{
struct tc3589x_gpio *tc3589x_gpio = to_tc3589x_gpio(chip);
struct tc3589x *tc3589x = tc3589x_gpio->tc3589x;
u8 reg = TC3589x_GPIODATA0 + (offset / 8) * 2;
unsigned pos = offset % 8;
u8 data[] = {!!val << pos, 1 << pos};
tc3589x_block_write(tc3589x, reg, ARRAY_SIZE(data), data);
}
static int tc3589x_gpio_direction_output(struct gpio_chip *chip,
unsigned offset, int val)
{
struct tc3589x_gpio *tc3589x_gpio = to_tc3589x_gpio(chip);
struct tc3589x *tc3589x = tc3589x_gpio->tc3589x;
u8 reg = TC3589x_GPIODIR0 + offset / 8;
unsigned pos = offset % 8;
tc3589x_gpio_set(chip, offset, val);
return tc3589x_set_bits(tc3589x, reg, 1 << pos, 1 << pos);
}
static int tc3589x_gpio_direction_input(struct gpio_chip *chip,
unsigned offset)
{
struct tc3589x_gpio *tc3589x_gpio = to_tc3589x_gpio(chip);
struct tc3589x *tc3589x = tc3589x_gpio->tc3589x;
u8 reg = TC3589x_GPIODIR0 + offset / 8;
unsigned pos = offset % 8;
return tc3589x_set_bits(tc3589x, reg, 1 << pos, 0);
}
static struct gpio_chip template_chip = {
.label = "tc3589x",
.owner = THIS_MODULE,
.direction_input = tc3589x_gpio_direction_input,
.get = tc3589x_gpio_get,
.direction_output = tc3589x_gpio_direction_output,
.set = tc3589x_gpio_set,
.can_sleep = true,
};
static int tc3589x_gpio_irq_set_type(struct irq_data *d, unsigned int type)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct tc3589x_gpio *tc3589x_gpio = to_tc3589x_gpio(gc);
int offset = d->hwirq;
int regoffset = offset / 8;
int mask = 1 << (offset % 8);
if (type == IRQ_TYPE_EDGE_BOTH) {
tc3589x_gpio->regs[REG_IBE][regoffset] |= mask;
return 0;
}
tc3589x_gpio->regs[REG_IBE][regoffset] &= ~mask;
if (type == IRQ_TYPE_LEVEL_LOW || type == IRQ_TYPE_LEVEL_HIGH)
tc3589x_gpio->regs[REG_IS][regoffset] |= mask;
else
tc3589x_gpio->regs[REG_IS][regoffset] &= ~mask;
if (type == IRQ_TYPE_EDGE_RISING || type == IRQ_TYPE_LEVEL_HIGH)
tc3589x_gpio->regs[REG_IEV][regoffset] |= mask;
else
tc3589x_gpio->regs[REG_IEV][regoffset] &= ~mask;
return 0;
}
static void tc3589x_gpio_irq_lock(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct tc3589x_gpio *tc3589x_gpio = to_tc3589x_gpio(gc);
mutex_lock(&tc3589x_gpio->irq_lock);
}
static void tc3589x_gpio_irq_sync_unlock(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct tc3589x_gpio *tc3589x_gpio = to_tc3589x_gpio(gc);
struct tc3589x *tc3589x = tc3589x_gpio->tc3589x;
static const u8 regmap[] = {
[REG_IBE] = TC3589x_GPIOIBE0,
[REG_IEV] = TC3589x_GPIOIEV0,
[REG_IS] = TC3589x_GPIOIS0,
[REG_IE] = TC3589x_GPIOIE0,
};
int i, j;
for (i = 0; i < CACHE_NR_REGS; i++) {
for (j = 0; j < CACHE_NR_BANKS; j++) {
u8 old = tc3589x_gpio->oldregs[i][j];
u8 new = tc3589x_gpio->regs[i][j];
if (new == old)
continue;
tc3589x_gpio->oldregs[i][j] = new;
tc3589x_reg_write(tc3589x, regmap[i] + j * 8, new);
}
}
mutex_unlock(&tc3589x_gpio->irq_lock);
}
static void tc3589x_gpio_irq_mask(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct tc3589x_gpio *tc3589x_gpio = to_tc3589x_gpio(gc);
int offset = d->hwirq;
int regoffset = offset / 8;
int mask = 1 << (offset % 8);
tc3589x_gpio->regs[REG_IE][regoffset] &= ~mask;
}
static void tc3589x_gpio_irq_unmask(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct tc3589x_gpio *tc3589x_gpio = to_tc3589x_gpio(gc);
int offset = d->hwirq;
int regoffset = offset / 8;
int mask = 1 << (offset % 8);
tc3589x_gpio->regs[REG_IE][regoffset] |= mask;
}
static struct irq_chip tc3589x_gpio_irq_chip = {
.name = "tc3589x-gpio",
.irq_bus_lock = tc3589x_gpio_irq_lock,
.irq_bus_sync_unlock = tc3589x_gpio_irq_sync_unlock,
.irq_mask = tc3589x_gpio_irq_mask,
.irq_unmask = tc3589x_gpio_irq_unmask,
.irq_set_type = tc3589x_gpio_irq_set_type,
};
static irqreturn_t tc3589x_gpio_irq(int irq, void *dev)
{
struct tc3589x_gpio *tc3589x_gpio = dev;
struct tc3589x *tc3589x = tc3589x_gpio->tc3589x;
u8 status[CACHE_NR_BANKS];
int ret;
int i;
ret = tc3589x_block_read(tc3589x, TC3589x_GPIOMIS0,
ARRAY_SIZE(status), status);
if (ret < 0)
return IRQ_NONE;
for (i = 0; i < ARRAY_SIZE(status); i++) {
unsigned int stat = status[i];
if (!stat)
continue;
while (stat) {
int bit = __ffs(stat);
int line = i * 8 + bit;
int irq = irq_find_mapping(tc3589x_gpio->chip.irqdomain,
line);
handle_nested_irq(irq);
stat &= ~(1 << bit);
}
tc3589x_reg_write(tc3589x, TC3589x_GPIOIC0 + i, status[i]);
}
return IRQ_HANDLED;
}
static int tc3589x_gpio_probe(struct platform_device *pdev)
{
struct tc3589x *tc3589x = dev_get_drvdata(pdev->dev.parent);
struct device_node *np = pdev->dev.of_node;
struct tc3589x_gpio *tc3589x_gpio;
int ret;
int irq;
if (!np) {
dev_err(&pdev->dev, "No Device Tree node found\n");
return -EINVAL;
}
irq = platform_get_irq(pdev, 0);
if (irq < 0)
return irq;
tc3589x_gpio = devm_kzalloc(&pdev->dev, sizeof(struct tc3589x_gpio),
GFP_KERNEL);
if (!tc3589x_gpio)
return -ENOMEM;
mutex_init(&tc3589x_gpio->irq_lock);
tc3589x_gpio->dev = &pdev->dev;
tc3589x_gpio->tc3589x = tc3589x;
tc3589x_gpio->chip = template_chip;
tc3589x_gpio->chip.ngpio = tc3589x->num_gpio;
tc3589x_gpio->chip.dev = &pdev->dev;
tc3589x_gpio->chip.base = -1;
tc3589x_gpio->chip.of_node = np;
/* Bring the GPIO module out of reset */
ret = tc3589x_set_bits(tc3589x, TC3589x_RSTCTRL,
TC3589x_RSTCTRL_GPIRST, 0);
if (ret < 0)
return ret;
ret = devm_request_threaded_irq(&pdev->dev,
irq, NULL, tc3589x_gpio_irq,
IRQF_ONESHOT, "tc3589x-gpio",
tc3589x_gpio);
if (ret) {
dev_err(&pdev->dev, "unable to get irq: %d\n", ret);
return ret;
}
ret = gpiochip_add(&tc3589x_gpio->chip);
if (ret) {
dev_err(&pdev->dev, "unable to add gpiochip: %d\n", ret);
return ret;
}
ret = gpiochip_irqchip_add(&tc3589x_gpio->chip,
&tc3589x_gpio_irq_chip,
0,
handle_simple_irq,
IRQ_TYPE_NONE);
if (ret) {
dev_err(&pdev->dev,
"could not connect irqchip to gpiochip\n");
return ret;
}
gpiochip_set_chained_irqchip(&tc3589x_gpio->chip,
&tc3589x_gpio_irq_chip,
irq,
NULL);
platform_set_drvdata(pdev, tc3589x_gpio);
return 0;
}
static int tc3589x_gpio_remove(struct platform_device *pdev)
{
struct tc3589x_gpio *tc3589x_gpio = platform_get_drvdata(pdev);
gpiochip_remove(&tc3589x_gpio->chip);
return 0;
}
static struct platform_driver tc3589x_gpio_driver = {
.driver.name = "tc3589x-gpio",
.driver.owner = THIS_MODULE,
.probe = tc3589x_gpio_probe,
.remove = tc3589x_gpio_remove,
};
static int __init tc3589x_gpio_init(void)
{
return platform_driver_register(&tc3589x_gpio_driver);
}
subsys_initcall(tc3589x_gpio_init);
static void __exit tc3589x_gpio_exit(void)
{
platform_driver_unregister(&tc3589x_gpio_driver);
}
module_exit(tc3589x_gpio_exit);
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("TC3589x GPIO driver");
MODULE_AUTHOR("Hanumath Prasad, Rabin Vincent");