diff options
| author | Rabin Vincent <rabin@rab.in> | 2015-07-22 16:05:18 +0300 |
|---|---|---|
| committer | Linus Walleij <linus.walleij@linaro.org> | 2015-07-27 16:01:05 +0300 |
| commit | 91492a44b998cf762150de8f1b40bda1902e8ea7 (patch) | |
| tree | 31ca1c400a6e8d0921125fbe20b156eb35db25de | |
| parent | 1296fba1a397b173d45534885a0934a7c005d7e3 (diff) | |
| download | linux-91492a44b998cf762150de8f1b40bda1902e8ea7.tar.xz | |
gpio: generic: support input-only chips
Allow chips to indicates that they are input-only and thus cannot set
the output value. This will be used by the gpio-etraxfs driver.
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
| -rw-r--r-- | drivers/gpio/gpio-generic.c | 23 | ||||
| -rw-r--r-- | include/linux/basic_mmio_gpio.h | 1 |
2 files changed, 21 insertions, 3 deletions
diff --git a/drivers/gpio/gpio-generic.c b/drivers/gpio/gpio-generic.c index 802e6d2c64e9..a3f07537fe62 100644 --- a/drivers/gpio/gpio-generic.c +++ b/drivers/gpio/gpio-generic.c @@ -153,6 +153,10 @@ static int bgpio_get(struct gpio_chip *gc, unsigned int gpio) return !!(bgc->read_reg(bgc->reg_dat) & bgc->pin2mask(bgc, gpio)); } +static void bgpio_set_none(struct gpio_chip *gc, unsigned int gpio, int val) +{ +} + static void bgpio_set(struct gpio_chip *gc, unsigned int gpio, int val) { struct bgpio_chip *bgc = to_bgpio_chip(gc); @@ -279,6 +283,12 @@ static int bgpio_simple_dir_in(struct gpio_chip *gc, unsigned int gpio) return 0; } +static int bgpio_dir_out_err(struct gpio_chip *gc, unsigned int gpio, + int val) +{ + return -EINVAL; +} + static int bgpio_simple_dir_out(struct gpio_chip *gc, unsigned int gpio, int val) { @@ -460,6 +470,9 @@ static int bgpio_setup_io(struct bgpio_chip *bgc, bgc->reg_set = set; bgc->gc.set = bgpio_set_set; bgc->gc.set_multiple = bgpio_set_multiple_set; + } else if (flags & BGPIOF_NO_OUTPUT) { + bgc->gc.set = bgpio_set_none; + bgc->gc.set_multiple = NULL; } else { bgc->gc.set = bgpio_set; bgc->gc.set_multiple = bgpio_set_multiple; @@ -476,7 +489,8 @@ static int bgpio_setup_io(struct bgpio_chip *bgc, static int bgpio_setup_direction(struct bgpio_chip *bgc, void __iomem *dirout, - void __iomem *dirin) + void __iomem *dirin, + unsigned long flags) { if (dirout && dirin) { return -EINVAL; @@ -491,7 +505,10 @@ static int bgpio_setup_direction(struct bgpio_chip *bgc, bgc->gc.direction_input = bgpio_dir_in_inv; bgc->gc.get_direction = bgpio_get_dir_inv; } else { - bgc->gc.direction_output = bgpio_simple_dir_out; + if (flags & BGPIOF_NO_OUTPUT) + bgc->gc.direction_output = bgpio_dir_out_err; + else + bgc->gc.direction_output = bgpio_simple_dir_out; bgc->gc.direction_input = bgpio_simple_dir_in; } @@ -543,7 +560,7 @@ int bgpio_init(struct bgpio_chip *bgc, struct device *dev, if (ret) return ret; - ret = bgpio_setup_direction(bgc, dirout, dirin); + ret = bgpio_setup_direction(bgc, dirout, dirin, flags); if (ret) return ret; diff --git a/include/linux/basic_mmio_gpio.h b/include/linux/basic_mmio_gpio.h index 14eea946e640..ed3768f4ecc7 100644 --- a/include/linux/basic_mmio_gpio.h +++ b/include/linux/basic_mmio_gpio.h @@ -75,5 +75,6 @@ int bgpio_init(struct bgpio_chip *bgc, struct device *dev, #define BGPIOF_UNREADABLE_REG_DIR BIT(2) /* reg_dir is unreadable */ #define BGPIOF_BIG_ENDIAN_BYTE_ORDER BIT(3) #define BGPIOF_READ_OUTPUT_REG_SET BIT(4) /* reg_set stores output value */ +#define BGPIOF_NO_OUTPUT BIT(5) /* only input */ #endif /* __BASIC_MMIO_GPIO_H */ |