diff options
author | Philipp Zabel <p.zabel@pengutronix.de> | 2014-01-07 11:34:11 (GMT) |
---|---|---|
committer | Linus Walleij <linus.walleij@linaro.org> | 2014-02-07 08:47:02 (GMT) |
commit | ef70bbe1aaa612f75360e5df5952fddec50b7ca9 (patch) | |
tree | 2f80756c83780e9ed9c67401af16022a749543c0 /drivers/gpio/gpiolib.c | |
parent | 25b35da7f4cce82271859f1b6eabd9f3bd41a2bb (diff) | |
download | linux-ef70bbe1aaa612f75360e5df5952fddec50b7ca9.tar.xz |
gpio: make gpiod_direction_output take a logical value
The documentation was not clear about whether
gpio_direction_output should take a logical value or the physical
level on the output line, i.e. whether the ACTIVE_LOW status
would be taken into account.
This converts gpiod_direction_output to use the logical level
and adds a new gpiod_direction_output_raw for the raw value.
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'drivers/gpio/gpiolib.c')
-rw-r--r-- | drivers/gpio/gpiolib.c | 67 |
1 files changed, 48 insertions, 19 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 50c4922..80da9f1 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -350,9 +350,9 @@ static ssize_t gpio_direction_store(struct device *dev, if (!test_bit(FLAG_EXPORT, &desc->flags)) status = -EIO; else if (sysfs_streq(buf, "high")) - status = gpiod_direction_output(desc, 1); + status = gpiod_direction_output_raw(desc, 1); else if (sysfs_streq(buf, "out") || sysfs_streq(buf, "low")) - status = gpiod_direction_output(desc, 0); + status = gpiod_direction_output_raw(desc, 0); else if (sysfs_streq(buf, "in")) status = gpiod_direction_input(desc); else @@ -1590,7 +1590,7 @@ int gpio_request_one(unsigned gpio, unsigned long flags, const char *label) if (flags & GPIOF_DIR_IN) err = gpiod_direction_input(desc); else - err = gpiod_direction_output(desc, + err = gpiod_direction_output_raw(desc, (flags & GPIOF_INIT_HIGH) ? 1 : 0); if (err) @@ -1756,28 +1756,13 @@ fail: } EXPORT_SYMBOL_GPL(gpiod_direction_input); -/** - * gpiod_direction_output - set the GPIO direction to input - * @desc: GPIO to set to output - * @value: initial output value of the GPIO - * - * Set the direction of the passed GPIO to output, such as gpiod_set_value() can - * be called safely on it. The initial value of the output must be specified. - * - * Return 0 in case of success, else an error code. - */ -int gpiod_direction_output(struct gpio_desc *desc, int value) +static int _gpiod_direction_output_raw(struct gpio_desc *desc, int value) { unsigned long flags; struct gpio_chip *chip; int status = -EINVAL; int offset; - if (!desc || !desc->chip) { - pr_warn("%s: invalid GPIO\n", __func__); - return -EINVAL; - } - /* GPIOs used for IRQs shall not be set as output */ if (test_bit(FLAG_USED_AS_IRQ, &desc->flags)) { gpiod_err(desc, @@ -1840,6 +1825,50 @@ fail: gpiod_dbg(desc, "%s: gpio status %d\n", __func__, status); return status; } + +/** + * gpiod_direction_output_raw - set the GPIO direction to output + * @desc: GPIO to set to output + * @value: initial output value of the GPIO + * + * Set the direction of the passed GPIO to output, such as gpiod_set_value() can + * be called safely on it. The initial value of the output must be specified + * as raw value on the physical line without regard for the ACTIVE_LOW status. + * + * Return 0 in case of success, else an error code. + */ +int gpiod_direction_output_raw(struct gpio_desc *desc, int value) +{ + if (!desc || !desc->chip) { + pr_warn("%s: invalid GPIO\n", __func__); + return -EINVAL; + } + return _gpiod_direction_output_raw(desc, value); +} +EXPORT_SYMBOL_GPL(gpiod_direction_output_raw); + +/** + * gpiod_direction_output - set the GPIO direction to input + * @desc: GPIO to set to output + * @value: initial output value of the GPIO + * + * Set the direction of the passed GPIO to output, such as gpiod_set_value() can + * be called safely on it. The initial value of the output must be specified + * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into + * account. + * + * Return 0 in case of success, else an error code. + */ +int gpiod_direction_output(struct gpio_desc *desc, int value) +{ + if (!desc || !desc->chip) { + pr_warn("%s: invalid GPIO\n", __func__); + return -EINVAL; + } + if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) + value = !value; + return _gpiod_direction_output_raw(desc, value); +} EXPORT_SYMBOL_GPL(gpiod_direction_output); /** |