[Gc-linux-cvs] linux/drivers/gpio gpiolib.c,1.1,1.2

[Albert H. <he...@us...>]

Update of /cvsroot/gc-linux/linux/drivers/gpio
In directory ddv4jf1.ch3.sourceforge.com:/tmp/cvs-serv503/drivers/gpio

Modified Files:
	gpiolib.c 
Log Message:
[PATCH] gpiolib: add gpio_direction_is_output

From: Albert Herranz <alb...@ya...>
Date: Sun, 1 Mar 2009 19:10:07 +0100
Subject: [PATCH] gpiolib: add gpio_direction_is_output

Add a function to determine if a given gpio has been already configured
as an output.
This is handy for drivers that require changing multiple times the direction
of a gpio and want to easily avoid redundant direction changes.

Signed-off-by: Albert Herranz <alb...@ya...>


Index: gpiolib.c
===================================================================
RCS file: /cvsroot/gc-linux/linux/drivers/gpio/gpiolib.c,v
retrieving revision 1.1
retrieving revision 1.2
diff -C2 -d -r1.1 -r1.2
*** gpiolib.c	2 Mar 2009 18:33:09 -0000	1.1
--- gpiolib.c	2 Mar 2009 18:33:59 -0000	1.2
***************
*** 997,1000 ****
--- 997,1018 ----
  EXPORT_SYMBOL_GPL(gpio_direction_output);
  
+ /**
+  * gpio_direction_is_output - tell if a gpio is configured as an output
+  * @gpio: gpio in question
+  *
+  * Returns a negative errno if the given gpio is not valid.
+  * Returns a positive non-zero if the gpio is configured as an output.
+  * Returns zero otherwise.
+  */
+ int gpio_direction_is_output(unsigned gpio)
+ {
+ 	struct gpio_desc *desc = &gpio_desc[gpio];
+ 
+ 	if (!gpio_is_valid(gpio))
+ 		return -EINVAL;
+ 
+ 	return test_bit(FLAG_IS_OUT, &desc->flags);
+ }
+ EXPORT_SYMBOL_GPL(gpio_direction_is_output);
  
  /* I/O calls are only valid after configuration completed; the relevant