linux/drivers/gpio/gpio-tc3589x.c
Mika Westerberg 2956b5d94a pinctrl / gpio: Introduce .set_config() callback for GPIO chips
Currently we already have two pin configuration related callbacks
available for GPIO chips .set_single_ended() and .set_debounce(). In
future we expect to have even more, which does not scale well if we need
to add yet another callback to the GPIO chip structure for each possible
configuration parameter.

Better solution is to reuse what we already have available in the
generic pinconf.

To support this, we introduce a new .set_config() callback for GPIO
chips. The callback takes a single packed pin configuration value as
parameter. This can then be extended easily beyond what is currently
supported by just adding new types to the generic pinconf enum.

If the GPIO driver is backed up by a pinctrl driver the GPIO driver can
just assign gpiochip_generic_config() (introduced in this patch) to
.set_config and that will take care configuration requests are directed
to the pinctrl driver.

We then convert the existing drivers over .set_config() and finally
remove the .set_single_ended() and .set_debounce() callbacks.

Suggested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-26 15:27:37 +01:00

369 lines
9.6 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/init.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/gpio/driver.h>
#include <linux/of.h>
#include <linux/interrupt.h>
#include <linux/mfd/tc3589x.h>
#include <linux/bitops.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 int tc3589x_gpio_get(struct gpio_chip *chip, unsigned int offset)
{
struct tc3589x_gpio *tc3589x_gpio = gpiochip_get_data(chip);
struct tc3589x *tc3589x = tc3589x_gpio->tc3589x;
u8 reg = TC3589x_GPIODATA0 + (offset / 8) * 2;
u8 mask = BIT(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 int offset, int val)
{
struct tc3589x_gpio *tc3589x_gpio = gpiochip_get_data(chip);
struct tc3589x *tc3589x = tc3589x_gpio->tc3589x;
u8 reg = TC3589x_GPIODATA0 + (offset / 8) * 2;
unsigned int pos = offset % 8;
u8 data[] = {val ? BIT(pos) : 0, BIT(pos)};
tc3589x_block_write(tc3589x, reg, ARRAY_SIZE(data), data);
}
static int tc3589x_gpio_direction_output(struct gpio_chip *chip,
unsigned int offset, int val)
{
struct tc3589x_gpio *tc3589x_gpio = gpiochip_get_data(chip);
struct tc3589x *tc3589x = tc3589x_gpio->tc3589x;
u8 reg = TC3589x_GPIODIR0 + offset / 8;
unsigned int pos = offset % 8;
tc3589x_gpio_set(chip, offset, val);
return tc3589x_set_bits(tc3589x, reg, BIT(pos), BIT(pos));
}
static int tc3589x_gpio_direction_input(struct gpio_chip *chip,
unsigned int offset)
{
struct tc3589x_gpio *tc3589x_gpio = gpiochip_get_data(chip);
struct tc3589x *tc3589x = tc3589x_gpio->tc3589x;
u8 reg = TC3589x_GPIODIR0 + offset / 8;
unsigned int pos = offset % 8;
return tc3589x_set_bits(tc3589x, reg, BIT(pos), 0);
}
static int tc3589x_gpio_get_direction(struct gpio_chip *chip,
unsigned int offset)
{
struct tc3589x_gpio *tc3589x_gpio = gpiochip_get_data(chip);
struct tc3589x *tc3589x = tc3589x_gpio->tc3589x;
u8 reg = TC3589x_GPIODIR0 + offset / 8;
unsigned int pos = offset % 8;
int ret;
ret = tc3589x_reg_read(tc3589x, reg);
if (ret < 0)
return ret;
return !(ret & BIT(pos));
}
static int tc3589x_gpio_set_config(struct gpio_chip *chip, unsigned int offset,
unsigned long config)
{
struct tc3589x_gpio *tc3589x_gpio = gpiochip_get_data(chip);
struct tc3589x *tc3589x = tc3589x_gpio->tc3589x;
/*
* These registers are alterated at each second address
* ODM bit 0 = drive to GND or Hi-Z (open drain)
* ODM bit 1 = drive to VDD or Hi-Z (open source)
*/
u8 odmreg = TC3589x_GPIOODM0 + (offset / 8) * 2;
u8 odereg = TC3589x_GPIOODE0 + (offset / 8) * 2;
unsigned int pos = offset % 8;
int ret;
switch (pinconf_to_config_param(config)) {
case PIN_CONFIG_DRIVE_OPEN_DRAIN:
/* Set open drain mode */
ret = tc3589x_set_bits(tc3589x, odmreg, BIT(pos), 0);
if (ret)
return ret;
/* Enable open drain/source mode */
return tc3589x_set_bits(tc3589x, odereg, BIT(pos), BIT(pos));
case PIN_CONFIG_DRIVE_OPEN_SOURCE:
/* Set open source mode */
ret = tc3589x_set_bits(tc3589x, odmreg, BIT(pos), BIT(pos));
if (ret)
return ret;
/* Enable open drain/source mode */
return tc3589x_set_bits(tc3589x, odereg, BIT(pos), BIT(pos));
case PIN_CONFIG_DRIVE_PUSH_PULL:
/* Disable open drain/source mode */
return tc3589x_set_bits(tc3589x, odereg, BIT(pos), 0);
default:
break;
}
return -ENOTSUPP;
}
static const struct gpio_chip template_chip = {
.label = "tc3589x",
.owner = THIS_MODULE,
.get = tc3589x_gpio_get,
.set = tc3589x_gpio_set,
.direction_output = tc3589x_gpio_direction_output,
.direction_input = tc3589x_gpio_direction_input,
.get_direction = tc3589x_gpio_get_direction,
.set_config = tc3589x_gpio_set_config,
.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 = gpiochip_get_data(gc);
int offset = d->hwirq;
int regoffset = offset / 8;
int mask = BIT(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 = gpiochip_get_data(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 = gpiochip_get_data(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 = gpiochip_get_data(gc);
int offset = d->hwirq;
int regoffset = offset / 8;
int mask = BIT(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 = gpiochip_get_data(gc);
int offset = d->hwirq;
int regoffset = offset / 8;
int mask = BIT(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.parent = &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 = devm_gpiochip_add_data(&pdev->dev, &tc3589x_gpio->chip,
tc3589x_gpio);
if (ret) {
dev_err(&pdev->dev, "unable to add gpiochip: %d\n", ret);
return ret;
}
ret = gpiochip_irqchip_add_nested(&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_nested_irqchip(&tc3589x_gpio->chip,
&tc3589x_gpio_irq_chip,
irq);
platform_set_drvdata(pdev, tc3589x_gpio);
return 0;
}
static struct platform_driver tc3589x_gpio_driver = {
.driver.name = "tc3589x-gpio",
.probe = tc3589x_gpio_probe,
};
static int __init tc3589x_gpio_init(void)
{
return platform_driver_register(&tc3589x_gpio_driver);
}
subsys_initcall(tc3589x_gpio_init);