From 46158aad96b0a90b52fd345f89951a50b3d1a81f Mon Sep 17 00:00:00 2001 From: Roland Stigge Date: Mon, 5 Mar 2012 23:01:11 +0100 Subject: GPIO: LPC32xx: Add output reading to GPO P3 The chip offers the function to detect the current state of output of the GPO P3 pins. Useful for reading GPIO output state in Linux' GPIO API, e.g. via sysfs. Please note that this only reads back the currently programmed output state, not the actual electrical level in terms of a GPI function. Finally, GPO3 is still just an output. Signed-off-by: Roland Stigge Acked-by: Arnd Bergmann Signed-off-by: Grant Likely --- drivers/gpio/gpio-lpc32xx.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) (limited to 'drivers/gpio') diff --git a/drivers/gpio/gpio-lpc32xx.c b/drivers/gpio/gpio-lpc32xx.c index 14a2f297a0b4..61c2d08d37b6 100644 --- a/drivers/gpio/gpio-lpc32xx.c +++ b/drivers/gpio/gpio-lpc32xx.c @@ -62,9 +62,11 @@ #define GPIO3_PIN_IN_SEL(x, y) (((x) >> GPIO3_PIN_IN_SHIFT(y)) & 1) #define GPIO3_PIN5_IN_SEL(x) (((x) >> 24) & 1) #define GPI3_PIN_IN_SEL(x, y) (((x) >> (y)) & 1) +#define GPO3_PIN_IN_SEL(x, y) (((x) >> (y)) & 1) struct gpio_regs { void __iomem *inp_state; + void __iomem *outp_state; void __iomem *outp_set; void __iomem *outp_clr; void __iomem *dir_set; @@ -145,6 +147,7 @@ static struct gpio_regs gpio_grp_regs_p2 = { static struct gpio_regs gpio_grp_regs_p3 = { .inp_state = LPC32XX_GPIO_P3_INP_STATE, + .outp_state = LPC32XX_GPIO_P3_OUTP_STATE, .outp_set = LPC32XX_GPIO_P3_OUTP_SET, .outp_clr = LPC32XX_GPIO_P3_OUTP_CLR, .dir_set = LPC32XX_GPIO_P2_DIR_SET, @@ -240,6 +243,12 @@ static int __get_gpi_state_p3(struct lpc32xx_gpio_chip *group, return GPI3_PIN_IN_SEL(__raw_readl(group->gpio_grp->inp_state), pin); } +static int __get_gpo_state_p3(struct lpc32xx_gpio_chip *group, + unsigned pin) +{ + return GPO3_PIN_IN_SEL(__raw_readl(group->gpio_grp->outp_state), pin); +} + /* * GENERIC_GPIO primitives. */ @@ -340,6 +349,13 @@ static void lpc32xx_gpo_set_value(struct gpio_chip *chip, unsigned pin, __set_gpo_level_p3(group, pin, value); } +static int lpc32xx_gpo_get_value(struct gpio_chip *chip, unsigned pin) +{ + struct lpc32xx_gpio_chip *group = to_lpc32xx_gpio(chip); + + return __get_gpo_state_p3(group, pin); +} + static int lpc32xx_gpio_request(struct gpio_chip *chip, unsigned pin) { if (pin < chip->ngpio) @@ -427,6 +443,7 @@ static struct lpc32xx_gpio_chip lpc32xx_gpiochip[] = { .label = "gpo_p3", .direction_output = lpc32xx_gpio_dir_out_always, .set = lpc32xx_gpo_set_value, + .get = lpc32xx_gpo_get_value, .request = lpc32xx_gpio_request, .base = LPC32XX_GPO_P3_GRP, .ngpio = LPC32XX_GPO_P3_MAX, -- cgit v1.2.3