leds: pwm: Use struct_size() helper

One of the more common cases of allocation size calculations is finding the size of a structure that has a zero-sized array at the end, along with memory for some number of elements for that array. For example:

struct led_pwm_priv {
	...
        struct led_pwm_data leds[0];
};

Make use of the struct_size() helper instead of an open-coded version in order to avoid any potential type mistakes.

So, replace the following function:

static inline size_t sizeof_pwm_leds_priv(int num_leds) {
return sizeof(struct led_pwm_priv) +
(sizeof(struct led_pwm_data) * num_leds);
}

with:

struct_size(priv, leds, count)

This code was detected with the help of Coccinelle.

Signed-off-by Gustavo A. R. Silva <[email protected]>

---
 drivers/leds/leds-pwm.c | 8 +-------
 1 file changed, 1 insertion(+), 7 deletions(-)

drivers/leds/leds-pwm.c +1 -7

index d0e1f2710351..8b6965a563e9 100644
@@ -65,12 +65,6 @@ static int led_pwm_set(struct led_classdev *led_cdev,
 	return 0;
 }
 
-static inline size_t sizeof_pwm_leds_priv(int num_leds)
-{
-	return sizeof(struct led_pwm_priv) +
-		      (sizeof(struct led_pwm_data) * num_leds);
-}
-
 static int led_pwm_add(struct device *dev, struct led_pwm_priv *priv,
 		       struct led_pwm *led, struct fwnode_handle *fwnode)
 {

@@ -174,7 +168,7 @@ static int led_pwm_probe(struct platform_device *pdev)
 	if (!count)
 		return -EINVAL;
 
-	priv = devm_kzalloc(&pdev->dev, sizeof_pwm_leds_priv(count),
+	priv = devm_kzalloc(&pdev->dev, struct_size(priv, leds, count),
 			    GFP_KERNEL);
 	if (!priv)
 		return -ENOMEM;

Signature · 1 line

2.23.0

One of the more common cases of allocation size calculations is finding the size of a structure that has a zero-sized array at the end, along with memory for some number of elements for that array. For example:

struct led_pwm_priv {
	...
        struct led_pwm_data leds[0];
};

Make use of the struct_size() helper instead of an open-coded version in order to avoid any potential type mistakes.

So, replace the following function:

static inline size_t sizeof_pwm_leds_priv(int num_leds) {
return sizeof(struct led_pwm_priv) +
(sizeof(struct led_pwm_data) * num_leds);
}

with:

struct_size(priv, leds, count)

This code was detected with the help of Coccinelle.

Signed-off-by Gustavo A. R. Silva <[email protected]>

---
 drivers/leds/leds-pwm.c | 8 +-------
 1 file changed, 1 insertion(+), 7 deletions(-)

drivers/leds/leds-pwm.c +0 -6

index d0e1f2710351..8b6965a563e9 100644
@@ -65,12 +65,6 @@ static int led_pwm_set(struct led_classdev *led_cdev,
 	return 0;
 }
 
-static inline size_t sizeof_pwm_leds_priv(int num_leds)
-{
-	return sizeof(struct led_pwm_priv) +
-		      (sizeof(struct led_pwm_data) * num_leds);
-}
-
 static int led_pwm_add(struct device *dev, struct led_pwm_priv *priv,
 		       struct led_pwm *led, struct fwnode_handle *fwnode)
 {