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>

diff --git a/drivers/leds/leds-ns2.c b/drivers/leds/leds-ns2.c
index e02b3136273f997ce0f04ae8d09b21b6ebbe6ea6..70137b1eecf5bdebe130a9f3a079567bb53df9c3 100644 (file)
--- 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);