X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=Documentation%2Fgpio.txt;h=8a7c45956d2412d69a26f8de991db19ed25a838f;hb=0f6d504e73b49374c6093efe6aa60ab55058248a;hp=18022e249c53dc1ad991d74d160551fa32f32070;hpb=81faaae45701484bd7368336e02f2a846153b22f;p=linux-2.6-omap-h63xx.git

diff --git a/Documentation/gpio.txt b/Documentation/gpio.txt
index 18022e249c5..8a7c45956d2 100644
--- a/Documentation/gpio.txt
+++ b/Documentation/gpio.txt
@@ -264,7 +264,7 @@ map between them using calls like:
 	/* map GPIO numbers to IRQ numbers */
 	int gpio_to_irq(unsigned gpio);
 
-	/* map IRQ numbers to GPIO numbers */
+	/* map IRQ numbers to GPIO numbers (avoid using this) */
 	int irq_to_gpio(unsigned irq);
 
 Those return either the corresponding number in the other namespace, or
@@ -284,7 +284,8 @@ system wakeup capabilities.
 
 Non-error values returned from irq_to_gpio() would most commonly be used
 with gpio_get_value(), for example to initialize or update driver state
-when the IRQ is edge-triggered.
+when the IRQ is edge-triggered.  Note that some platforms don't support
+this reverse mapping, so you should avoid using it.
 
 
 Emulating Open Drain Signals