diff options
| author | Weike Chen <alvin.chen@intel.com> | 2014-09-17 09:18:41 -0700 |
|---|---|---|
| committer | Linus Walleij <linus.walleij@linaro.org> | 2014-09-23 17:51:38 +0200 |
| commit | 5d60d9efe1447b46f33075fb5841fd83247cdbb2 (patch) | |
| tree | a947ba97594ecc9c521cfd08ab5f29541ba221e2 /drivers/gpio | |
| parent | 67809b974a07042dc61cb9d06e30df7a5f25446a (diff) | |
| download | linux-5d60d9efe1447b46f33075fb5841fd83247cdbb2.tar.bz2 | |
GPIO: gpio-dwapb: Support Debounce
This patch enables 'debounce' for the designware GPIO, and
it is based on Josef Ahmad's previous work.
Reviewed-by: Hock Leong Kweh <hock.leong.kweh@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Weike Chen <alvin.chen@intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'drivers/gpio')
| -rw-r--r-- | drivers/gpio/gpio-dwapb.c | 36 |
1 files changed, 34 insertions, 2 deletions
diff --git a/drivers/gpio/gpio-dwapb.c b/drivers/gpio/gpio-dwapb.c index 551eaf7208f4..db059bb8edc3 100644 --- a/drivers/gpio/gpio-dwapb.c +++ b/drivers/gpio/gpio-dwapb.c @@ -37,6 +37,7 @@ #define GPIO_INTTYPE_LEVEL 0x38 #define GPIO_INT_POLARITY 0x3c #define GPIO_INTSTATUS 0x40 +#define GPIO_PORTA_DEBOUNCE 0x48 #define GPIO_PORTA_EOI 0x4c #define GPIO_EXT_PORTA 0x50 #define GPIO_EXT_PORTB 0x54 @@ -64,6 +65,12 @@ struct dwapb_gpio { struct irq_domain *domain; }; +static inline struct dwapb_gpio_port * +to_dwapb_gpio_port(struct bgpio_chip *bgc) +{ + return container_of(bgc, struct dwapb_gpio_port, bgc); +} + static inline u32 dwapb_read(struct dwapb_gpio *gpio, unsigned int offset) { struct bgpio_chip *bgc = &gpio->ports[0].bgc; @@ -84,8 +91,7 @@ static inline void dwapb_write(struct dwapb_gpio *gpio, unsigned int offset, static int dwapb_gpio_to_irq(struct gpio_chip *gc, unsigned offset) { struct bgpio_chip *bgc = to_bgpio_chip(gc); - struct dwapb_gpio_port *port = container_of(bgc, struct - dwapb_gpio_port, bgc); + struct dwapb_gpio_port *port = to_dwapb_gpio_port(bgc); struct dwapb_gpio *gpio = port->gpio; return irq_find_mapping(gpio->domain, offset); @@ -235,6 +241,28 @@ static int dwapb_irq_set_type(struct irq_data *d, u32 type) return 0; } +static int dwapb_gpio_set_debounce(struct gpio_chip *gc, + unsigned offset, unsigned debounce) +{ + struct bgpio_chip *bgc = to_bgpio_chip(gc); + struct dwapb_gpio_port *port = to_dwapb_gpio_port(bgc); + struct dwapb_gpio *gpio = port->gpio; + unsigned long flags, val_deb; + unsigned long mask = bgc->pin2mask(bgc, offset); + + spin_lock_irqsave(&bgc->lock, flags); + + val_deb = dwapb_read(gpio, GPIO_PORTA_DEBOUNCE); + if (debounce) + dwapb_write(gpio, GPIO_PORTA_DEBOUNCE, val_deb | mask); + else + dwapb_write(gpio, GPIO_PORTA_DEBOUNCE, val_deb & ~mask); + + spin_unlock_irqrestore(&bgc->lock, flags); + + return 0; +} + static irqreturn_t dwapb_irq_handler_mfd(int irq, void *dev_id) { u32 worked; @@ -373,6 +401,10 @@ static int dwapb_gpio_add_port(struct dwapb_gpio *gpio, port->bgc.gc.ngpio = pp->ngpio; port->bgc.gc.base = pp->gpio_base; + /* Only port A support debounce */ + if (pp->idx == 0) + port->bgc.gc.set_debounce = dwapb_gpio_set_debounce; + if (pp->irq) dwapb_configure_irqs(gpio, port, pp); |