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>
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 @@
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 @@
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 @@
}
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 @@
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);
/**