[PATCH 3/4 v5] GPIO: gpio-dwapb: Support Debounce
From: Weike Chen <hidden>
Date: 2014-09-17 08:26:44
Also in:
linux-gpio, lkml
Subsystem:
gpio subsystem, synopsys designware apb gpio driver, the rest · Maintainers:
Linus Walleij, Bartosz Golaszewski, Hoan Tran, Linus Torvalds
This patch enables 'debounce' for the designware GPIO, and it is based on Josef Ahmad's previous work. Reviewed-by: Hock Leong Kweh <redacted> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Weike Chen <redacted> --- drivers/gpio/gpio-dwapb.c | 36 ++++++++++++++++++++++++++++++++++-- 1 file changed, 34 insertions(+), 2 deletions(-)
diff --git a/drivers/gpio/gpio-dwapb.c b/drivers/gpio/gpio-dwapb.c
index 551eaf7..db059bb 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);
--
1.7.9.5