diff options
Diffstat (limited to 'drivers/gpio/gpio-tc3589x.c')
| -rw-r--r-- | drivers/gpio/gpio-tc3589x.c | 368 |
1 files changed, 368 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-tc3589x.c b/drivers/gpio/gpio-tc3589x.c new file mode 100644 index 000000000..1436098b1 --- /dev/null +++ b/drivers/gpio/gpio-tc3589x.c @@ -0,0 +1,368 @@ +/* + * 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, 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.irq.domain, + 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); |