[PATCH] Define a NO_GPIO macro to compare against and to use as aninvalid GPIO

From: Guennadi Liakhovetski
Date: Thu Jan 31 2008 - 10:26:38 EST


As discussed on i2c mailing list with David Brownell, and number
outside of the 0...MAX_INT range is invalid as a GPIO number.
Define a macro, similar to NO_IRQ, to be used as a deliberate
invalid GPIO, rather than defining a is_valid_gpio() macro.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@xxxxxxxxxxxxxx>

---

As gpiolib doesn't seem to have an own mailing list, sending it directly
to LKML.

include/asm-generic/gpio.h | 4 ++++
1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/include/asm-generic/gpio.h b/include/asm-generic/gpio.h
index f29a502..806b86c 100644
--- a/include/asm-generic/gpio.h
+++ b/include/asm-generic/gpio.h
@@ -16,6 +16,10 @@
#define ARCH_NR_GPIOS 256
#endif

+#ifndef NO_GPIO
+#define NO_GPIO ((unsigned int)-1)
+#endif
+
struct seq_file;

/**
--
1.5.3.4
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/