diff options
author | Michael Hennerich <michael.hennerich@analog.com> | 2010-10-27 15:33:19 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2010-10-27 18:03:07 -0700 |
commit | 459773ae8dbbd480886d186181c6bc2e8556025f (patch) | |
tree | 38d738b858105a46a473bcae0958e2ded77a2e21 /drivers/gpio/adp5588-gpio.c | |
parent | ead6db084392349ad33323b1bb2916058dd7e82b (diff) | |
download | linux-459773ae8dbbd480886d186181c6bc2e8556025f.tar.gz |
gpio: adp5588-gpio: support interrupt controller
Implement irq_chip functionality on ADP5588/5587 GPIO expanders. Only
level sensitive interrupts are supported. Interrupts provided by this
irq_chip must be requested using request_threaded_irq().
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/gpio/adp5588-gpio.c')
-rw-r--r-- | drivers/gpio/adp5588-gpio.c | 277 |
1 files changed, 256 insertions, 21 deletions
diff --git a/drivers/gpio/adp5588-gpio.c b/drivers/gpio/adp5588-gpio.c index 2e8e9e24f887..0871f78af593 100644 --- a/drivers/gpio/adp5588-gpio.c +++ b/drivers/gpio/adp5588-gpio.c @@ -1,8 +1,8 @@ /* * GPIO Chip driver for Analog Devices - * ADP5588 I/O Expander and QWERTY Keypad Controller + * ADP5588/ADP5587 I/O Expander and QWERTY Keypad Controller * - * Copyright 2009 Analog Devices Inc. + * Copyright 2009-2010 Analog Devices Inc. * * Licensed under the GPL-2 or later. */ @@ -13,21 +13,34 @@ #include <linux/init.h> #include <linux/i2c.h> #include <linux/gpio.h> +#include <linux/interrupt.h> +#include <linux/irq.h> #include <linux/i2c/adp5588.h> -#define DRV_NAME "adp5588-gpio" -#define MAXGPIO 18 -#define ADP_BANK(offs) ((offs) >> 3) -#define ADP_BIT(offs) (1u << ((offs) & 0x7)) +#define DRV_NAME "adp5588-gpio" + +/* + * Early pre 4.0 Silicon required to delay readout by at least 25ms, + * since the Event Counter Register updated 25ms after the interrupt + * asserted. + */ +#define WA_DELAYED_READOUT_REVID(rev) ((rev) < 4) struct adp5588_gpio { struct i2c_client *client; struct gpio_chip gpio_chip; struct mutex lock; /* protect cached dir, dat_out */ + /* protect serialized access to the interrupt controller bus */ + struct mutex irq_lock; unsigned gpio_start; + unsigned irq_base; uint8_t dat_out[3]; uint8_t dir[3]; + uint8_t int_lvl[3]; + uint8_t int_en[3]; + uint8_t irq_mask[3]; + uint8_t irq_stat[3]; }; static int adp5588_gpio_read(struct i2c_client *client, u8 reg) @@ -55,8 +68,8 @@ static int adp5588_gpio_get_value(struct gpio_chip *chip, unsigned off) struct adp5588_gpio *dev = container_of(chip, struct adp5588_gpio, gpio_chip); - return !!(adp5588_gpio_read(dev->client, GPIO_DAT_STAT1 + ADP_BANK(off)) - & ADP_BIT(off)); + return !!(adp5588_gpio_read(dev->client, + GPIO_DAT_STAT1 + ADP5588_BANK(off)) & ADP5588_BIT(off)); } static void adp5588_gpio_set_value(struct gpio_chip *chip, @@ -66,8 +79,8 @@ static void adp5588_gpio_set_value(struct gpio_chip *chip, struct adp5588_gpio *dev = container_of(chip, struct adp5588_gpio, gpio_chip); - bank = ADP_BANK(off); - bit = ADP_BIT(off); + bank = ADP5588_BANK(off); + bit = ADP5588_BIT(off); mutex_lock(&dev->lock); if (val) @@ -87,10 +100,10 @@ static int adp5588_gpio_direction_input(struct gpio_chip *chip, unsigned off) struct adp5588_gpio *dev = container_of(chip, struct adp5588_gpio, gpio_chip); - bank = ADP_BANK(off); + bank = ADP5588_BANK(off); mutex_lock(&dev->lock); - dev->dir[bank] &= ~ADP_BIT(off); + dev->dir[bank] &= ~ADP5588_BIT(off); ret = adp5588_gpio_write(dev->client, GPIO_DIR1 + bank, dev->dir[bank]); mutex_unlock(&dev->lock); @@ -105,8 +118,8 @@ static int adp5588_gpio_direction_output(struct gpio_chip *chip, struct adp5588_gpio *dev = container_of(chip, struct adp5588_gpio, gpio_chip); - bank = ADP_BANK(off); - bit = ADP_BIT(off); + bank = ADP5588_BANK(off); + bit = ADP5588_BIT(off); mutex_lock(&dev->lock); dev->dir[bank] |= bit; @@ -125,6 +138,213 @@ static int adp5588_gpio_direction_output(struct gpio_chip *chip, return ret; } +#ifdef CONFIG_GPIO_ADP5588_IRQ +static int adp5588_gpio_to_irq(struct gpio_chip *chip, unsigned off) +{ + struct adp5588_gpio *dev = + container_of(chip, struct adp5588_gpio, gpio_chip); + return dev->irq_base + off; +} + +static void adp5588_irq_bus_lock(unsigned int irq) +{ + struct adp5588_gpio *dev = get_irq_chip_data(irq); + mutex_lock(&dev->irq_lock); +} + + /* + * genirq core code can issue chip->mask/unmask from atomic context. + * This doesn't work for slow busses where an access needs to sleep. + * bus_sync_unlock() is therefore called outside the atomic context, + * syncs the current irq mask state with the slow external controller + * and unlocks the bus. + */ + +static void adp5588_irq_bus_sync_unlock(unsigned int irq) +{ + struct adp5588_gpio *dev = get_irq_chip_data(irq); + int i; + + for (i = 0; i <= ADP5588_BANK(ADP5588_MAXGPIO); i++) + if (dev->int_en[i] ^ dev->irq_mask[i]) { + dev->int_en[i] = dev->irq_mask[i]; + adp5588_gpio_write(dev->client, GPIO_INT_EN1 + i, + dev->int_en[i]); + } + + mutex_unlock(&dev->irq_lock); +} + +static void adp5588_irq_mask(unsigned int irq) +{ + struct adp5588_gpio *dev = get_irq_chip_data(irq); + unsigned gpio = irq - dev->irq_base; + + dev->irq_mask[ADP5588_BANK(gpio)] &= ~ADP5588_BIT(gpio); +} + +static void adp5588_irq_unmask(unsigned int irq) +{ + struct adp5588_gpio *dev = get_irq_chip_data(irq); + unsigned gpio = irq - dev->irq_base; + + dev->irq_mask[ADP5588_BANK(gpio)] |= ADP5588_BIT(gpio); +} + +static int adp5588_irq_set_type(unsigned int irq, unsigned int type) +{ + struct adp5588_gpio *dev = get_irq_chip_data(irq); + uint16_t gpio = irq - dev->irq_base; + unsigned bank, bit; + + if ((type & IRQ_TYPE_EDGE_BOTH)) { + dev_err(&dev->client->dev, "irq %d: unsupported type %d\n", + irq, type); + return -EINVAL; + } + + bank = ADP5588_BANK(gpio); + bit = ADP5588_BIT(gpio); + + if (type & IRQ_TYPE_LEVEL_HIGH) + dev->int_lvl[bank] |= bit; + else if (type & IRQ_TYPE_LEVEL_LOW) + dev->int_lvl[bank] &= ~bit; + else + return -EINVAL; + + adp5588_gpio_direction_input(&dev->gpio_chip, gpio); + adp5588_gpio_write(dev->client, GPIO_INT_LVL1 + bank, + dev->int_lvl[bank]); + + return 0; +} + +static struct irq_chip adp5588_irq_chip = { + .name = "adp5588", + .mask = adp5588_irq_mask, + .unmask = adp5588_irq_unmask, + .bus_lock = adp5588_irq_bus_lock, + .bus_sync_unlock = adp5588_irq_bus_sync_unlock, + .set_type = adp5588_irq_set_type, +}; + +static int adp5588_gpio_read_intstat(struct i2c_client *client, u8 *buf) +{ + int ret = i2c_smbus_read_i2c_block_data(client, GPIO_INT_STAT1, 3, buf); + + if (ret < 0) + dev_err(&client->dev, "Read INT_STAT Error\n"); + + return ret; +} + +static irqreturn_t adp5588_irq_handler(int irq, void *devid) +{ + struct adp5588_gpio *dev = devid; + unsigned status, bank, bit, pending; + int ret; + status = adp5588_gpio_read(dev->client, INT_STAT); + + if (status & ADP5588_GPI_INT) { + ret = adp5588_gpio_read_intstat(dev->client, dev->irq_stat); + if (ret < 0) + memset(dev->irq_stat, 0, ARRAY_SIZE(dev->irq_stat)); + + for (bank = 0; bank <= ADP5588_BANK(ADP5588_MAXGPIO); + bank++, bit = 0) { + pending = dev->irq_stat[bank] & dev->irq_mask[bank]; + + while (pending) { + if (pending & (1 << bit)) { + handle_nested_irq(dev->irq_base + + (bank << 3) + bit); + pending &= ~(1 << bit); + + } + bit++; + } + } + } + + adp5588_gpio_write(dev->client, INT_STAT, status); /* Status is W1C */ + + return IRQ_HANDLED; +} + +static int adp5588_irq_setup(struct adp5588_gpio *dev) +{ + struct i2c_client *client = dev->client; + struct adp5588_gpio_platform_data *pdata = client->dev.platform_data; + unsigned gpio; + int ret; + + adp5588_gpio_write(client, CFG, ADP5588_AUTO_INC); + adp5588_gpio_write(client, INT_STAT, -1); /* status is W1C */ + adp5588_gpio_read_intstat(client, dev->irq_stat); /* read to clear */ + + dev->irq_base = pdata->irq_base; + mutex_init(&dev->irq_lock); + + for (gpio = 0; gpio < dev->gpio_chip.ngpio; gpio++) { + int irq = gpio + dev->irq_base; + set_irq_chip_data(irq, dev); + set_irq_chip_and_handler(irq, &adp5588_irq_chip, + handle_level_irq); + set_irq_nested_thread(irq, 1); +#ifdef CONFIG_ARM + /* + * ARM needs us to explicitly flag the IRQ as VALID, + * once we do so, it will also set the noprobe. + */ + set_irq_flags(irq, IRQF_VALID); +#else + set_irq_noprobe(irq); +#endif + } + + ret = request_threaded_irq(client->irq, + NULL, + adp5588_irq_handler, + IRQF_TRIGGER_FALLING | IRQF_ONESHOT, + dev_name(&client->dev), dev); + if (ret) { + dev_err(&client->dev, "failed to request irq %d\n", + client->irq); + goto out; + } + + dev->gpio_chip.to_irq = adp5588_gpio_to_irq; + adp5588_gpio_write(client, CFG, + ADP5588_AUTO_INC | ADP5588_INT_CFG | ADP5588_GPI_INT); + + return 0; + +out: + dev->irq_base = 0; + return ret; +} + +static void adp5588_irq_teardown(struct adp5588_gpio *dev) +{ + if (dev->irq_base) + free_irq(dev->client->irq, dev); +} + +#else +static int adp5588_irq_setup(struct adp5588_gpio *dev) +{ + struct i2c_client *client = dev->client; + dev_warn(&client->dev, "interrupt support not compiled in\n"); + + return 0; +} + +static void adp5588_irq_teardown(struct adp5588_gpio *dev) +{ +} +#endif /* CONFIG_GPIO_ADP5588_IRQ */ + static int __devinit adp5588_gpio_probe(struct i2c_client *client, const struct i2c_device_id *id) { @@ -160,37 +380,46 @@ static int __devinit adp5588_gpio_probe(struct i2c_client *client, gc->can_sleep = 1; gc->base = pdata->gpio_start; - gc->ngpio = MAXGPIO; + gc->ngpio = ADP5588_MAXGPIO; gc->label = client->name; gc->owner = THIS_MODULE; mutex_init(&dev->lock); - ret = adp5588_gpio_read(dev->client, DEV_ID); if (ret < 0) goto err; revid = ret & ADP5588_DEVICE_ID_MASK; - for (i = 0, ret = 0; i <= ADP_BANK(MAXGPIO); i++) { + for (i = 0, ret = 0; i <= ADP5588_BANK(ADP5588_MAXGPIO); i++) { dev->dat_out[i] = adp5588_gpio_read(client, GPIO_DAT_OUT1 + i); dev->dir[i] = adp5588_gpio_read(client, GPIO_DIR1 + i); ret |= adp5588_gpio_write(client, KP_GPIO1 + i, 0); ret |= adp5588_gpio_write(client, GPIO_PULL1 + i, (pdata->pullup_dis_mask >> (8 * i)) & 0xFF); - + ret |= adp5588_gpio_write(client, GPIO_INT_EN1 + i, 0); if (ret) goto err; } + if (pdata->irq_base) { + if (WA_DELAYED_READOUT_REVID(revid)) { + dev_warn(&client->dev, "GPIO int not supported\n"); + } else { + ret = adp5588_irq_setup(dev); + if (ret) + goto err; + } + } + ret = gpiochip_add(&dev->gpio_chip); if (ret) - goto err; + goto err_irq; - dev_info(&client->dev, "gpios %d..%d on a %s Rev. %d\n", + dev_info(&client->dev, "gpios %d..%d (IRQ Base %d) on a %s Rev. %d\n", gc->base, gc->base + gc->ngpio - 1, - client->name, revid); + pdata->irq_base, client->name, revid); if (pdata->setup) { ret = pdata->setup(client, gc->base, gc->ngpio, pdata->context); @@ -199,8 +428,11 @@ static int __devinit adp5588_gpio_probe(struct i2c_client *client, } i2c_set_clientdata(client, dev); + return 0; +err_irq: + adp5588_irq_teardown(dev); err: kfree(dev); return ret; @@ -222,6 +454,9 @@ static int __devexit adp5588_gpio_remove(struct i2c_client *client) } } + if (dev->irq_base) + free_irq(dev->client->irq, dev); + ret = gpiochip_remove(&dev->gpio_chip); if (ret) { dev_err(&client->dev, "gpiochip_remove failed %d\n", ret); |