diff options
Diffstat (limited to 'drivers/gpio')
| -rw-r--r-- | drivers/gpio/Kconfig | 7 | ||||
| -rw-r--r-- | drivers/gpio/pca953x.c | 249 |
2 files changed, 244 insertions, 12 deletions
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig index f3549b8..c5cc7d9 100644 --- a/drivers/gpio/Kconfig +++ b/drivers/gpio/Kconfig @@ -134,6 +134,13 @@ config GPIO_PCA953X This driver can also be built as a module. If so, the module will be called pca953x. +config GPIO_PCA953X_IRQ + bool "Interrupt controller support for PCA953x" + depends on GPIO_PCA953X=y + help + Say yes here to enable the pca953x to be used as an interrupt + controller. It requires the driver to be built in the kernel. + config GPIO_PCF857X tristate "PCF857x, PCA{85,96}7x, and MAX732[89] I2C GPIO expanders" depends on I2C diff --git a/drivers/gpio/pca953x.c b/drivers/gpio/pca953x.c index 6a2fb3f..ab5daab 100644 --- a/drivers/gpio/pca953x.c +++ b/drivers/gpio/pca953x.c @@ -14,6 +14,8 @@ #include <linux/module.h> #include <linux/init.h> #include <linux/gpio.h> +#include <linux/interrupt.h> +#include <linux/irq.h> #include <linux/i2c.h> #include <linux/i2c/pca953x.h> #ifdef CONFIG_OF_GPIO @@ -26,23 +28,28 @@ #define PCA953X_INVERT 2 #define PCA953X_DIRECTION 3 +#define PCA953X_GPIOS 0x00FF +#define PCA953X_INT 0x0100 + static const struct i2c_device_id pca953x_id[] = { - { "pca9534", 8, }, - { "pca9535", 16, }, + { "pca9534", 8 | PCA953X_INT, }, + { "pca9535", 16 | PCA953X_INT, }, { "pca9536", 4, }, - { "pca9537", 4, }, - { "pca9538", 8, }, - { "pca9539", 16, }, - { "pca9554", 8, }, - { "pca9555", 16, }, + { "pca9537", 4 | PCA953X_INT, }, + { "pca9538", 8 | PCA953X_INT, }, + { "pca9539", 16 | PCA953X_INT, }, + { "pca9554", 8 | PCA953X_INT, }, + { "pca9555", 16 | PCA953X_INT, }, { "pca9556", 8, }, { "pca9557", 8, }, { "max7310", 8, }, - { "max7315", 8, }, - { "pca6107", 8, }, - { "tca6408", 8, }, - { "tca6416", 16, }, + { "max7312", 16 | PCA953X_INT, }, + { "max7313", 16 | PCA953X_INT, }, + { "max7315", 8 | PCA953X_INT, }, + { "pca6107", 8 | PCA953X_INT, }, + { "tca6408", 8 | PCA953X_INT, }, + { "tca6416", 16 | PCA953X_INT, }, /* NYET: { "tca6424", 24, }, */ { } }; @@ -53,6 +60,15 @@ struct pca953x_chip { uint16_t reg_output; uint16_t reg_direction; +#ifdef CONFIG_GPIO_PCA953X_IRQ + struct mutex irq_lock; + uint16_t irq_mask; + uint16_t irq_stat; + uint16_t irq_trig_raise; + uint16_t irq_trig_fall; + int irq_base; +#endif + struct i2c_client *client; struct pca953x_platform_data *dyn_pdata; struct gpio_chip gpio_chip; @@ -202,6 +218,210 @@ static void pca953x_setup_gpio(struct pca953x_chip *chip, int gpios) gc->names = chip->names; } +#ifdef CONFIG_GPIO_PCA953X_IRQ +static int pca953x_gpio_to_irq(struct gpio_chip *gc, unsigned off) +{ + struct pca953x_chip *chip; + + chip = container_of(gc, struct pca953x_chip, gpio_chip); + return chip->irq_base + off; +} + +static void pca953x_irq_mask(unsigned int irq) +{ + struct pca953x_chip *chip = get_irq_chip_data(irq); + + chip->irq_mask &= ~(1 << (irq - chip->irq_base)); +} + +static void pca953x_irq_unmask(unsigned int irq) +{ + struct pca953x_chip *chip = get_irq_chip_data(irq); + + chip->irq_mask |= 1 << (irq - chip->irq_base); +} + +static void pca953x_irq_bus_lock(unsigned int irq) +{ + struct pca953x_chip *chip = get_irq_chip_data(irq); + + mutex_lock(&chip->irq_lock); +} + +static void pca953x_irq_bus_sync_unlock(unsigned int irq) +{ + struct pca953x_chip *chip = get_irq_chip_data(irq); + + mutex_unlock(&chip->irq_lock); +} + +static int pca953x_irq_set_type(unsigned int irq, unsigned int type) +{ + struct pca953x_chip *chip = get_irq_chip_data(irq); + uint16_t level = irq - chip->irq_base; + uint16_t mask = 1 << level; + + if (!(type & IRQ_TYPE_EDGE_BOTH)) { + dev_err(&chip->client->dev, "irq %d: unsupported type %d\n", + irq, type); + return -EINVAL; + } + + if (type & IRQ_TYPE_EDGE_FALLING) + chip->irq_trig_fall |= mask; + else + chip->irq_trig_fall &= ~mask; + + if (type & IRQ_TYPE_EDGE_RISING) + chip->irq_trig_raise |= mask; + else + chip->irq_trig_raise &= ~mask; + + return pca953x_gpio_direction_input(&chip->gpio_chip, level); +} + +static struct irq_chip pca953x_irq_chip = { + .name = "pca953x", + .mask = pca953x_irq_mask, + .unmask = pca953x_irq_unmask, + .bus_lock = pca953x_irq_bus_lock, + .bus_sync_unlock = pca953x_irq_bus_sync_unlock, + .set_type = pca953x_irq_set_type, +}; + +static uint16_t pca953x_irq_pending(struct pca953x_chip *chip) +{ + uint16_t cur_stat; + uint16_t old_stat; + uint16_t pending; + uint16_t trigger; + int ret; + + ret = pca953x_read_reg(chip, PCA953X_INPUT, &cur_stat); + if (ret) + return 0; + + /* Remove output pins from the equation */ + cur_stat &= chip->reg_direction; + + old_stat = chip->irq_stat; + trigger = (cur_stat ^ old_stat) & chip->irq_mask; + + if (!trigger) + return 0; + + chip->irq_stat = cur_stat; + + pending = (old_stat & chip->irq_trig_fall) | + (cur_stat & chip->irq_trig_raise); + pending &= trigger; + + return pending; +} + +static irqreturn_t pca953x_irq_handler(int irq, void *devid) +{ + struct pca953x_chip *chip = devid; + uint16_t pending; + uint16_t level; + + pending = pca953x_irq_pending(chip); + + if (!pending) + return IRQ_HANDLED; + + do { + level = __ffs(pending); + handle_nested_irq(level + chip->irq_base); + + pending &= ~(1 << level); + } while (pending); + + return IRQ_HANDLED; +} + +static int pca953x_irq_setup(struct pca953x_chip *chip, + const struct i2c_device_id *id) +{ + struct i2c_client *client = chip->client; + struct pca953x_platform_data *pdata = client->dev.platform_data; + int ret; + + if (pdata->irq_base && (id->driver_data & PCA953X_INT)) { + int lvl; + + ret = pca953x_read_reg(chip, PCA953X_INPUT, + &chip->irq_stat); + if (ret) + goto out_failed; + + /* + * There is no way to know which GPIO line generated the + * interrupt. We have to rely on the previous read for + * this purpose. + */ + chip->irq_stat &= chip->reg_direction; + chip->irq_base = pdata->irq_base; + mutex_init(&chip->irq_lock); + + for (lvl = 0; lvl < chip->gpio_chip.ngpio; lvl++) { + int irq = lvl + chip->irq_base; + + set_irq_chip_data(irq, chip); + set_irq_chip_and_handler(irq, &pca953x_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 + } + + ret = request_threaded_irq(client->irq, + NULL, + pca953x_irq_handler, + IRQF_TRIGGER_FALLING | IRQF_ONESHOT, + dev_name(&client->dev), chip); + if (ret) { + dev_err(&client->dev, "failed to request irq %d\n", + client->irq); + goto out_failed; + } + + chip->gpio_chip.to_irq = pca953x_gpio_to_irq; + } + + return 0; + +out_failed: + chip->irq_base = 0; + return ret; +} + +static void pca953x_irq_teardown(struct pca953x_chip *chip) +{ + if (chip->irq_base) + free_irq(chip->client->irq, chip); +} +#else /* CONFIG_GPIO_PCA953X_IRQ */ +static int pca953x_irq_setup(struct pca953x_chip *chip, + const struct i2c_device_id *id) +{ + struct i2c_client *client = chip->client; + struct pca953x_platform_data *pdata = client->dev.platform_data; + + if (pdata->irq_base && (id->driver_data & PCA953X_INT)) + dev_warn(&client->dev, "interrupt support not compiled in\n"); + + return 0; +} + +static void pca953x_irq_teardown(struct pca953x_chip *chip) +{ +} +#endif + /* * Handlers for alternative sources of platform_data */ @@ -286,7 +506,7 @@ static int __devinit pca953x_probe(struct i2c_client *client, /* initialize cached registers from their original values. * we can't share this chip with another i2c master. */ - pca953x_setup_gpio(chip, id->driver_data); + pca953x_setup_gpio(chip, id->driver_data & PCA953X_GPIOS); ret = pca953x_read_reg(chip, PCA953X_OUTPUT, &chip->reg_output); if (ret) @@ -301,6 +521,9 @@ static int __devinit pca953x_probe(struct i2c_client *client, if (ret) goto out_failed; + ret = pca953x_irq_setup(chip, id); + if (ret) + goto out_failed; ret = gpiochip_add(&chip->gpio_chip); if (ret) @@ -317,6 +540,7 @@ static int __devinit pca953x_probe(struct i2c_client *client, return 0; out_failed: + pca953x_irq_teardown(chip); kfree(chip->dyn_pdata); kfree(chip); return ret; @@ -345,6 +569,7 @@ static int pca953x_remove(struct i2c_client *client) return ret; } + pca953x_irq_teardown(chip); kfree(chip->dyn_pdata); kfree(chip); return 0; |
