gpio: define gpio_is_valid()
Introduce a gpio_is_valid() predicate; use it in gpiolib.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@pengutronix.de>
[ use inline function; follow the gpio_* naming convention;
work without gpiolib; all programming interfaces need docs ]
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/asm-generic/gpio.h b/include/asm-generic/gpio.h
index 7e77b6f..464c5b3 100644
--- a/include/asm-generic/gpio.h
+++ b/include/asm-generic/gpio.h
@@ -16,6 +16,12 @@
#define ARCH_NR_GPIOS 256
#endif
+static inline int gpio_is_valid(int number)
+{
+ /* only some non-negative numbers are valid */
+ return ((unsigned)number) < ARCH_NR_GPIOS;
+}
+
struct seq_file;
struct module;
@@ -99,6 +105,12 @@
#else
+static inline int gpio_is_valid(int number)
+{
+ /* only non-negative numbers are valid */
+ return number >= 0;
+}
+
/* platforms that don't directly support access to GPIOs through I2C, SPI,
* or other blocking infrastructure can use these wrappers.
*/