diff mbox

[v2] gpiolib: fix warning about iterator

Message ID 1451223410-8985-1-git-send-email-sudipm.mukherjee@gmail.com
State New
Headers show

Commit Message

Sudip Mukherjee Dec. 27, 2015, 1:36 p.m. UTC
We were getting build warning about "iterator" being used uninitialized.
Use iterator properly to fix the build warning and in the process remove
the variable "pos" which is not required now.

Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
---

v1: at the end of the loop iterator will point to head and we are trying
to check its field.

 drivers/gpio/gpiolib.c | 20 ++++++++++++--------
 1 file changed, 12 insertions(+), 8 deletions(-)

Comments

Linus Walleij Dec. 28, 2015, 12:35 a.m. UTC | #1
On Sun, Dec 27, 2015 at 2:36 PM, Sudip Mukherjee
<sudipm.mukherjee@gmail.com> wrote:

> We were getting build warning about "iterator" being used uninitialized.
> Use iterator properly to fix the build warning and in the process remove
> the variable "pos" which is not required now.
>
> Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
> ---
>
> v1: at the end of the loop iterator will point to head and we are trying
> to check its field.

OK took the v1 out and applied this version instead.

Yours,
Linus Walleij
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diff mbox

Patch

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index d72ac1f..6972b4e 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -189,23 +189,21 @@  EXPORT_SYMBOL_GPL(gpiod_get_direction);
  */
 static int gpiochip_add_to_list(struct gpio_chip *chip)
 {
-	struct list_head *pos;
 	struct gpio_chip *iterator;
 	struct gpio_chip *previous = NULL;
 
 	if (list_empty(&gpio_chips)) {
-		pos = gpio_chips.next;
-		goto found;
+		list_add_tail(&chip->list, &gpio_chips);
+		return 0;
 	}
 
-	list_for_each(pos, &gpio_chips) {
-		iterator = list_entry(pos, struct gpio_chip, list);
+	list_for_each_entry(iterator, &gpio_chips, list) {
 		if (iterator->base >= chip->base + chip->ngpio) {
 			/*
 			 * Iterator is the first GPIO chip so there is no
 			 * previous one
 			 */
-			if (previous == NULL) {
+			if (!previous) {
 				goto found;
 			} else {
 				/*
@@ -221,7 +219,13 @@  static int gpiochip_add_to_list(struct gpio_chip *chip)
 		previous = iterator;
 	}
 
-	/* We are beyond the last chip in the list */
+	/*
+	 * We are beyond the last chip in the list and iterator now
+	 * points to the head.
+	 * Let iterator point to the last chip in the list.
+	 */
+
+	iterator = list_last_entry(&gpio_chips, struct gpio_chip, list);
 	if (iterator->base + iterator->ngpio <= chip->base)
 		goto found;
 
@@ -230,7 +234,7 @@  static int gpiochip_add_to_list(struct gpio_chip *chip)
 	return -EBUSY;
 
 found:
-	list_add_tail(&chip->list, pos);
+	list_add_tail(&chip->list, &iterator->list);
 	return 0;
 }