diff options
author | Linus Walleij <linus.walleij@linaro.org> | 2018-09-03 09:52:10 +0200 |
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committer | Linus Walleij <linus.walleij@linaro.org> | 2018-09-10 08:48:51 +0200 |
commit | ab8c1e82935b8cd034d18c5d0cf944a532a83aea (patch) | |
tree | b0f936c0b05058c3521dedd8fe6c74784e42c9fe /drivers | |
parent | gpio: twl4030: Cut down boilerplate (diff) | |
download | linux-ab8c1e82935b8cd034d18c5d0cf944a532a83aea.tar.xz linux-ab8c1e82935b8cd034d18c5d0cf944a532a83aea.zip |
gpio: twl4030: Implement .get_direction()
It's nice to be able to read back the direction of the GPIO
line from the hardware so implement .get_direction() for
twl4030.
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/gpio/gpio-twl4030.c | 42 |
1 files changed, 41 insertions, 1 deletions
diff --git a/drivers/gpio/gpio-twl4030.c b/drivers/gpio/gpio-twl4030.c index 1e47ddff33f6..fbfb648d3502 100644 --- a/drivers/gpio/gpio-twl4030.c +++ b/drivers/gpio/gpio-twl4030.c @@ -154,6 +154,23 @@ static int twl4030_set_gpio_direction(int gpio, int is_input) return ret; } +static int twl4030_get_gpio_direction(int gpio) +{ + u8 d_bnk = gpio >> 3; + u8 d_msk = BIT(gpio & 0x7); + u8 base = REG_GPIODATADIR1 + d_bnk; + int ret = 0; + + ret = gpio_twl4030_read(base); + if (ret < 0) + return ret; + + /* 1 = output, but gpiolib semantics are inverse so invert */ + ret = !(ret & d_msk); + + return ret; +} + static int twl4030_set_gpio_dataout(int gpio, int enable) { u8 d_bnk = gpio >> 3; @@ -359,6 +376,28 @@ static int twl_direction_out(struct gpio_chip *chip, unsigned offset, int value) return ret; } +static int twl_get_direction(struct gpio_chip *chip, unsigned offset) +{ + struct gpio_twl4030_priv *priv = gpiochip_get_data(chip); + /* + * Default 0 = output + * LED GPIOs >= TWL4030_GPIO_MAX are always output + */ + int ret = 0; + + mutex_lock(&priv->mutex); + if (offset < TWL4030_GPIO_MAX) { + ret = twl4030_get_gpio_direction(offset); + if (ret) { + mutex_unlock(&priv->mutex); + return ret; + } + } + mutex_unlock(&priv->mutex); + + return ret; +} + static int twl_to_irq(struct gpio_chip *chip, unsigned offset) { struct gpio_twl4030_priv *priv = gpiochip_get_data(chip); @@ -374,8 +413,9 @@ static const struct gpio_chip template_chip = { .request = twl_request, .free = twl_free, .direction_input = twl_direction_in, - .get = twl_get, .direction_output = twl_direction_out, + .get_direction = twl_get_direction, + .get = twl_get, .set = twl_set, .to_irq = twl_to_irq, .can_sleep = true, |