leds: leds-ns2: fix oops at module removal

This patch fixes a regression introduced by commit 72052fcc10
("leds: leds-ns2: add device tree binding").

When the driver is initialized with device tree data, platform_data
pointer is NULL. This causes a kernel oops at removal.

To fix this bug, num_leds is moved into driver_data and platform_data
is not longer used from ns2_led_remove().

Signed-off-by: Simon Guinot <simon.guinot@sequanux.org>
Signed-off-by: Bryan Wu <cooloney@gmail.com>

1 files changed, 25 insertions, 13 deletions

diff --git a/drivers/leds/leds-ns2.c b/drivers/leds/leds-ns2.c
index e02b3136273f..70137b1eecf5 100644
--- a/drivers/leds/leds-ns2.c
+++ b/drivers/leds/leds-ns2.c
@@ -308,10 +308,21 @@ static const struct of_device_id of_ns2_leds_match[] = {
 };
 #endif /* CONFIG_OF_GPIO */
 
+struct ns2_led_priv {
+        int num_leds;
+        struct ns2_led_data leds_data[];
+};
+
+static inline int sizeof_ns2_led_priv(int num_leds)
+{
+        return sizeof(struct ns2_led_priv) +
+                      (sizeof(struct ns2_led_data) * num_leds);
+}
+
 static int ns2_led_probe(struct platform_device *pdev)
 {
         struct ns2_led_platform_data *pdata = pdev->dev.platform_data;
-        struct ns2_led_data *leds_data;
+        struct ns2_led_priv *priv;
         int i;
         int ret;
 
@@ -332,21 +343,23 @@ static int ns2_led_probe(struct platform_device *pdev)
                 return -EINVAL;
 #endif /* CONFIG_OF_GPIO */
 
-        leds_data = devm_kzalloc(&pdev->dev, sizeof(struct ns2_led_data) *
-                                 pdata->num_leds, GFP_KERNEL);
-        if (!leds_data)
+        priv = devm_kzalloc(&pdev->dev,
+                            sizeof_ns2_led_priv(pdata->num_leds), GFP_KERNEL);
+        if (!priv)
                 return -ENOMEM;
+        priv->num_leds = pdata->num_leds;
 
-        for (i = 0; i < pdata->num_leds; i++) {
-                ret = create_ns2_led(pdev, &leds_data[i], &pdata->leds[i]);
+        for (i = 0; i < priv->num_leds; i++) {
+                ret = create_ns2_led(pdev, &priv->leds_data[i],
+                                     &pdata->leds[i]);
                 if (ret < 0) {
                         for (i = i - 1; i >= 0; i--)
-                                delete_ns2_led(&leds_data[i]);
+                                delete_ns2_led(&priv->leds_data[i]);
                         return ret;
                 }
         }
 
-        platform_set_drvdata(pdev, leds_data);
+        platform_set_drvdata(pdev, priv);
 
         return 0;
 }
@@ -354,13 +367,12 @@ static int ns2_led_probe(struct platform_device *pdev)
 static int ns2_led_remove(struct platform_device *pdev)
 {
         int i;
-        struct ns2_led_platform_data *pdata = pdev->dev.platform_data;
-        struct ns2_led_data *leds_data;
+        struct ns2_led_priv *priv;
 
-        leds_data = platform_get_drvdata(pdev);
+        priv = platform_get_drvdata(pdev);
 
-        for (i = 0; i < pdata->num_leds; i++)
-                delete_ns2_led(&leds_data[i]);
+        for (i = 0; i < priv->num_leds; i++)
+                delete_ns2_led(&priv->leds_data[i]);
 
         platform_set_drvdata(pdev, NULL);