[PATCH v1 1/2] gpiolib: Unify expectations about ->request() returned value

[PATCH v1 1/2] gpiolib: Unify expectations about ->request() returned value

[Andy Shevchenko]

Half of the code in the GPIO library is written in an expectation that
any non-zero value returned from the ->request() callback is an error code,
while some code checks only for negative values.

Unify expectations about ->request() returned value to be non-zero
for an error and 0 for the success.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/gpio/gpiolib-sysfs.c | 2 +-
 drivers/gpio/gpiolib.c       | 6 +++---
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/gpio/gpiolib-sysfs.c b/drivers/gpio/gpiolib-sysfs.c
index fe580d6b8d0d..f3b886e2132c 100644
--- a/drivers/gpio/gpiolib-sysfs.c
+++ b/drivers/gpio/gpiolib-sysfs.c
@@ -476,7 +476,7 @@ static ssize_t export_store(struct class *class,
 	 */
 
 	status = gpiod_request(desc, "sysfs");
-	if (status < 0) {
+	if (status) {
 		if (status == -EPROBE_DEFER)
 			status = -ENODEV;
 		goto done;
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 4df1f1a23a8b..0e6dddce207d 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -1985,7 +1985,7 @@ static int gpiod_request_commit(struct gpio_desc *desc, const char *label)
 			ret = -EINVAL;
 		spin_lock_irqsave(&gpio_lock, flags);
 
-		if (ret < 0) {
+		if (ret) {
 			desc_set_label(desc, NULL);
 			kfree_const(label);
 			clear_bit(FLAG_REQUESTED, &desc->flags);
@@ -2051,7 +2051,7 @@ int gpiod_request(struct gpio_desc *desc, const char *label)
 
 	if (try_module_get(gdev->owner)) {
 		ret = gpiod_request_commit(desc, label);
-		if (ret < 0)
+		if (ret)
 			module_put(gdev->owner);
 		else
 			get_device(&gdev->dev);
@@ -3968,7 +3968,7 @@ struct gpio_desc *__must_check gpiod_get_index(struct device *dev,
 	 * the device name as label
 	 */
 	ret = gpiod_request(desc, con_id ? con_id : devname);
-	if (ret < 0) {
+	if (ret) {
 		if (ret == -EBUSY && flags & GPIOD_FLAGS_BIT_NONEXCLUSIVE) {
 			/*
 			 * This happens when there are several consumers for
-- 
2.28.0

[PATCH v1 2/2] gpiolib: split error path in gpiod_request_commit()

[Andy Shevchenko]

For better maintenance and micro optimization split error path
in the gpiod_request_commit().

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/gpio/gpiolib.c | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 0e6dddce207d..43ddcf454b5f 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -1968,11 +1968,9 @@ static int gpiod_request_commit(struct gpio_desc *desc, const char *label)
 
 	if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) {
 		desc_set_label(desc, label ? : "?");
-		ret = 0;
 	} else {
-		kfree_const(label);
 		ret = -EBUSY;
-		goto done;
+		goto out_free_unlock;
 	}
 
 	if (gc->request) {
@@ -1987,9 +1985,8 @@ static int gpiod_request_commit(struct gpio_desc *desc, const char *label)
 
 		if (ret) {
 			desc_set_label(desc, NULL);
-			kfree_const(label);
 			clear_bit(FLAG_REQUESTED, &desc->flags);
-			goto done;
+			goto out_free_unlock;
 		}
 	}
 	if (gc->get_direction) {
@@ -1998,8 +1995,12 @@ static int gpiod_request_commit(struct gpio_desc *desc, const char *label)
 		gpiod_get_direction(desc);
 		spin_lock_irqsave(&gpio_lock, flags);
 	}
-done:
 	spin_unlock_irqrestore(&gpio_lock, flags);
+	return 0;
+
+out_free_unlock:
+	spin_unlock_irqrestore(&gpio_lock, flags);
+	kfree_const(label);
 	return ret;
 }
 
-- 
2.28.0

Re: [PATCH v1 2/2] gpiolib: split error path in gpiod_request_commit()

[Bartosz Golaszewski]

On Wed, Oct 21, 2020 at 1:25 PM Andy Shevchenko
<andriy.shevchenko@linux.intel.com> wrote:
>
> For better maintenance and micro optimization split error path
> in the gpiod_request_commit().
>
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
>

Applied, thanks!

Bartosz

Re: [PATCH v1 1/2] gpiolib: Unify expectations about ->request() returned value

[Bartosz Golaszewski]

On Wed, Oct 21, 2020 at 1:25 PM Andy Shevchenko
<andriy.shevchenko@linux.intel.com> wrote:
>
> Half of the code in the GPIO library is written in an expectation that
> any non-zero value returned from the ->request() callback is an error code,
> while some code checks only for negative values.
>
> Unify expectations about ->request() returned value to be non-zero
> for an error and 0 for the success.
>
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---

Applied, thanks!

Bartosz