gpio: uapi: clarify the meaning of 'empty' char arrays
Clarify that a char array containing a string is considered 'empty' if
the first character is the null terminator. The remaining characters
are not relevant to this determination.
Signed-off-by: Kent Gibson <warthog618@gmail.com>
Reviewed-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20201005070329.21055-6-warthog618@gmail.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/include/uapi/linux/gpio.h b/include/uapi/linux/gpio.h
index ad3f56d..2072c26 100644
--- a/include/uapi/linux/gpio.h
+++ b/include/uapi/linux/gpio.h
@@ -26,7 +26,7 @@
* struct gpiochip_info - Information about a certain GPIO chip
* @name: the Linux kernel name of this GPIO chip
* @label: a functional name for this GPIO chip, such as a product
- * number, may be empty
+ * number, may be empty (i.e. label[0] == '\0')
* @lines: number of GPIO lines on this chip
*/
struct gpiochip_info {
@@ -203,7 +203,7 @@ struct gpio_v2_line_request {
* struct gpio_v2_line_info - Information about a certain GPIO line
* @name: the name of this GPIO line, such as the output pin of the line on
* the chip, a rail or a pin header name on a board, as specified by the
- * GPIO chip, may be empty
+ * GPIO chip, may be empty (i.e. name[0] == '\0')
* @consumer: a functional name for the consumer of this GPIO line as set
* by whatever is using it, will be empty if there is no current user but
* may also be empty if the consumer doesn't set this up
@@ -315,7 +315,7 @@ struct gpio_v2_line_event {
* @flags: various flags for this line
* @name: the name of this GPIO line, such as the output pin of the line on the
* chip, a rail or a pin header name on a board, as specified by the gpio
- * chip, may be empty
+ * chip, may be empty (i.e. name[0] == '\0')
* @consumer: a functional name for the consumer of this GPIO line as set by
* whatever is using it, will be empty if there is no current user but may
* also be empty if the consumer doesn't set this up