leds: cpcap: Add "blink" device file to control LED blinking

To avoid permission problems using the LED class trigger files

Signed-off-by: Mike Lockwood <lockwood@android.com>

diff --git a/drivers/leds/leds-ld-cpcap.c b/drivers/leds/leds-ld-cpcap.c
index 0c114f18c60831f98f4a06bfa994f6668be7c267..acd0fe4fe2271856d1a04e79bc0da5f7984164fe 100755 (executable)
--- a/drivers/leds/leds-ld-cpcap.c
+++ b/drivers/leds/leds-ld-cpcap.c
@@ -52,15 +52,10 @@ static void cpcap_set(struct led_classdev *led_cdev,
 }
 EXPORT_SYMBOL(cpcap_set);
 
-static int cpcap_led_blink(struct led_classdev *led_cdev,
-                              unsigned long *delay_on,
-                              unsigned long *delay_off)
+static void
+cpcap_led_set_blink(struct cpcap_led_data *info, unsigned long blink)
 {
-       struct cpcap_led_data *info =
-               container_of(led_cdev, struct cpcap_led_data,
-                        cpcap_class_dev);
-
-       info->blink_val = *delay_on;
+       info->blink_val = blink;
 
        if (info->pdata->blink_able) {
                if(info->blink_val) {
@@ -70,7 +65,17 @@ static int cpcap_led_blink(struct led_classdev *led_cdev,
                        schedule_work(&info->brightness_work);
                }
        }
+}
+
+static int cpcap_led_blink(struct led_classdev *led_cdev,
+                              unsigned long *delay_on,
+                              unsigned long *delay_off)
+{
+       struct cpcap_led_data *info =
+               container_of(led_cdev, struct cpcap_led_data,
+                        cpcap_class_dev);
 
+       cpcap_led_set_blink(info, *delay_on);
        return 0;
 }
 
@@ -134,6 +139,29 @@ static void cpcap_brightness_work(struct work_struct *work)
        }
 }
 
+static ssize_t blink_show(struct device *dev,
+               struct device_attribute *attr, char *buf)
+{
+       struct led_classdev *led_cdev = dev_get_drvdata(dev);
+       struct cpcap_led_data *info =
+               container_of(led_cdev, struct cpcap_led_data, cpcap_class_dev);
+
+       return sprintf(buf, "%u\n", info->blink_val);
+}
+
+static ssize_t blink_store(struct device *dev,
+               struct device_attribute *attr, const char *buf, size_t size)
+{
+       struct led_classdev *led_cdev = dev_get_drvdata(dev);
+       struct cpcap_led_data *info =
+               container_of(led_cdev, struct cpcap_led_data, cpcap_class_dev);
+       unsigned long blink = simple_strtoul(buf, NULL, 10);
+       cpcap_led_set_blink(info, blink);
+       return size;
+}
+
+static DEVICE_ATTR(blink, 0644, blink_show, blink_store);
+
 static int cpcap_probe(struct platform_device *pdev)
 {
        int ret = 0;
@@ -182,10 +210,22 @@ static int cpcap_probe(struct platform_device *pdev)
                goto err_reg_button_class_failed;
        }
 
+       /* Create a device file to control blinking.
+        * We do this to avoid problems setting permissions on the
+        * timer trigger delay_on and delay_off files.
+        */
+       ret = device_create_file(info->cpcap_class_dev.dev, &dev_attr_blink);
+       if (ret < 0) {
+               pr_err("%s:device_create_file failed for blink\n", __func__);
+               goto err_device_create_file_failed;
+       }
+
        INIT_WORK(&info->brightness_work, cpcap_brightness_work);
 
        return ret;
 
+err_device_create_file_failed:
+       led_classdev_unregister(&info->cpcap_class_dev);
 err_reg_button_class_failed:
        if (info->regulator)
                regulator_put(info->regulator);
@@ -198,6 +238,7 @@ static int cpcap_remove(struct platform_device *pdev)
 {
        struct cpcap_led_data *info = platform_get_drvdata(pdev);
 
+       device_remove_file(info->cpcap_class_dev.dev, &dev_attr_blink);
        if (info->regulator)
                regulator_put(info->regulator);
        led_classdev_unregister(&info->cpcap_class_dev);