Re: [patch 2.6.24-rc6-mm 2/9] gpiolib: add gpio provider infrastructure

[David Brownell <david-b@pacbell.net>]

On Friday 28 December 2007, Sam Ravnborg wrote:
> For this an the other setters of desc->label a small helper function
> would be better. The helper function could then contain the necessary
> ifdef in only one place.

Good point; see the appended.


> > +/* add/remove chips */
> > +extern int gpiochip_add(struct gpio_chip *chip);
> > +extern int __must_check gpiochip_remove(struct gpio_chip *chip);
> 
> The use of "extern" is not needed in .h files for function prototypes.

But it's widely used nonetheless, and many people prefer to
see those annotations.  Heck, /usr/include is full of them...

- Dave


============ CUT HERE
Minor gpiolib.c cleanup: remove most #ifdefs for CONFIG_FS.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
---
 drivers/gpio/gpiolib.c |   22 +++++++++++-----------
 1 file changed, 11 insertions(+), 11 deletions(-)

--- at91.orig/drivers/gpio/gpiolib.c
+++ at91/drivers/gpio/gpiolib.c
@@ -50,6 +50,12 @@ struct gpio_desc {
 };
 static struct gpio_desc gpio_desc[ARCH_NR_GPIOS];
 
+static inline void desc_set_label(struct gpio_desc *d, const char *label)
+{
+#ifdef CONFIG_DEBUG_FS
+	d->label = label;
+#endif
+}
 
 /* Warn when drivers omit gpio_request() calls -- legal but ill-advised
  * when setting direction, and otherwise illegal.  Until board setup code
@@ -61,9 +67,7 @@ static void gpio_ensure_requested(struct
 {
 	if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) {
 		pr_warning("GPIO-%d autorequested\n", (int)(desc - gpio_desc));
-#ifdef CONFIG_DEBUG_FS
-		desc->label = "[auto]";
-#endif
+		desc_set_label(desc, "[auto]");
 	}
 }
 
@@ -178,9 +182,7 @@ int gpio_request(unsigned gpio, const ch
 	 */
 
 	if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) {
-#ifdef CONFIG_DEBUG_FS
-		desc->label = (label == NULL) ? "?" : label;
-#endif
+		desc_set_label(desc, label ? : "?");
 		status = 0;
 	} else
 		status = -EBUSY;
@@ -207,11 +209,9 @@ void gpio_free(unsigned gpio)
 	spin_lock_irqsave(&gpio_lock, flags);
 
 	desc = &gpio_desc[gpio];
-	if (desc->chip && test_and_clear_bit(FLAG_REQUESTED, &desc->flags)) {
-#ifdef CONFIG_DEBUG_FS
-		desc->label = NULL;
-#endif
-	} else
+	if (desc->chip && test_and_clear_bit(FLAG_REQUESTED, &desc->flags))
+		desc_set_label(desc, NULL);
+	else
 		WARN_ON(extra_checks);
 
 	spin_unlock_irqrestore(&gpio_lock, flags);