compat: backport LED class software blinking

Signed-off-by: Felix Fietkau <nbd@openwrt.org>

diff --git a/compat/compat-2.6.37.c b/compat/compat-2.6.37.c
index 81f466f3b58a23f143d63ecf705556437f04d60d..669402d880d1e808be7fe3ce1dd8e7693d368c47 100644 (file)
--- a/compat/compat-2.6.37.c
+++ b/compat/compat-2.6.37.c
@@ -152,3 +152,175 @@ int compat_genl_unregister_family(struct genl_family *family)
 }
 EXPORT_SYMBOL(compat_genl_unregister_family);
 
+#ifdef CONFIG_LEDS_CLASS
+
+#undef led_brightness_set
+#undef led_classdev_unregister
+
+spinlock_t led_lock;
+static LIST_HEAD(led_timers);
+
+struct led_timer {
+       struct list_head list;
+       struct led_classdev *cdev;
+       struct timer_list blink_timer;
+       unsigned long blink_delay_on;
+       unsigned long blink_delay_off;
+       int blink_brightness;
+};
+
+static void led_brightness_set(struct led_classdev *led_cdev,
+                              enum led_brightness brightness)
+{
+       led_cdev->brightness = brightness;
+       led_cdev->brightness_set(led_cdev, brightness);
+}
+
+static struct led_timer *led_get_timer(struct led_classdev *led_cdev)
+{
+       struct led_timer *p;
+       unsigned long flags;
+
+       spin_lock_irqsave(&led_lock, flags);
+       list_for_each_entry(p, &led_timers, list) {
+               if (p->cdev == led_cdev)
+                       goto found;
+       }
+       p = NULL;
+found:
+       spin_unlock_irqrestore(&led_lock, flags);
+       return p;
+}
+
+static void led_stop_software_blink(struct led_timer *led)
+{
+       del_timer_sync(&led->blink_timer);
+       led->blink_delay_on = 0;
+       led->blink_delay_off = 0;
+}
+
+static void led_timer_function(unsigned long data)
+{
+       struct led_timer *led = (struct led_timer *)data;
+       unsigned long brightness;
+       unsigned long delay;
+
+       if (!led->blink_delay_on || !led->blink_delay_off) {
+               led->cdev->brightness_set(led->cdev, LED_OFF);
+               return;
+       }
+
+       brightness = led->cdev->brightness;
+       if (!brightness) {
+               /* Time to switch the LED on. */
+               brightness = led->blink_brightness;
+               delay = led->blink_delay_on;
+       } else {
+               /* Store the current brightness value to be able
+                * to restore it when the delay_off period is over.
+                */
+               led->blink_brightness = brightness;
+               brightness = LED_OFF;
+               delay = led->blink_delay_off;
+       }
+
+       led_brightness_set(led->cdev, brightness);
+       mod_timer(&led->blink_timer, jiffies + msecs_to_jiffies(delay));
+}
+
+static struct led_timer *led_new_timer(struct led_classdev *led_cdev)
+{
+       struct led_timer *led;
+       unsigned long flags;
+
+       led = kzalloc(sizeof(struct led_timer), GFP_ATOMIC);
+       if (!led)
+               return NULL;
+
+       led->cdev = led_cdev;
+       init_timer(&led->blink_timer);
+       led->blink_timer.function = led_timer_function;
+       led->blink_timer.data = (unsigned long) led;
+
+       spin_lock_irqsave(&led_lock, flags);
+       list_add(&led->list, &led_timers);
+       spin_unlock_irqrestore(&led_lock, flags);
+
+       return led;
+}
+
+void led_blink_set(struct led_classdev *led_cdev,
+                  unsigned long *delay_on,
+                  unsigned long *delay_off)
+{
+       struct led_timer *led = led_get_timer(led_cdev);
+       int current_brightness;
+
+       if (!led) {
+               led = led_new_timer(led_cdev);
+               if (!led)
+                       return;
+       }
+
+       /* blink with 1 Hz as default if nothing specified */
+       if (!*delay_on && !*delay_off)
+               *delay_on = *delay_off = 500;
+
+       if (led->blink_delay_on == *delay_on &&
+           led->blink_delay_off == *delay_off)
+               return;
+
+       current_brightness = led_cdev->brightness;
+       if (current_brightness)
+               led->blink_brightness = current_brightness;
+       if (!led->blink_brightness)
+               led->blink_brightness = led_cdev->max_brightness;
+
+       led_stop_software_blink(led);
+       led->blink_delay_on = *delay_on;
+       led->blink_delay_off = *delay_off;
+
+       /* never on - don't blink */
+       if (!*delay_on)
+               return;
+
+       /* never off - just set to brightness */
+       if (!*delay_off) {
+               led_brightness_set(led_cdev, led->blink_brightness);
+               return;
+       }
+
+       mod_timer(&led->blink_timer, jiffies + 1);
+}
+EXPORT_SYMBOL(led_blink_set);
+
+void compat_led_brightness_set(struct led_classdev *led_cdev,
+                              enum led_brightness brightness)
+{
+       struct led_timer *led = led_get_timer(led_cdev);
+
+       if (led)
+               led_stop_software_blink(led);
+
+       return led_cdev->brightness_set(led_cdev, brightness);
+}
+EXPORT_SYMBOL(compat_led_brightness_set);
+
+void compat_led_classdev_unregister(struct led_classdev *led_cdev)
+{
+       struct led_timer *led = led_get_timer(led_cdev);
+       unsigned long flags;
+
+       if (led) {
+               del_timer_sync(&led->blink_timer);
+               spin_lock_irqsave(&led_lock, flags);
+               list_del(&led->list);
+               spin_unlock_irqrestore(&led_lock, flags);
+               kfree(led);
+       }
+
+       led_classdev_unregister(led_cdev);
+}
+EXPORT_SYMBOL(compat_led_classdev_unregister);
+
+#endif

diff --git a/include/linux/compat-2.6.37.h b/include/linux/compat-2.6.37.h
index 6c026a34c31857a9c6229c530ce3c04ea82790e9..502d2b198340376308a95c519f4099eefe2898f8 100644 (file)
--- a/include/linux/compat-2.6.37.h
+++ b/include/linux/compat-2.6.37.h
@@ -6,6 +6,7 @@
 #if (LINUX_VERSION_CODE < KERNEL_VERSION(2,6,37))
 
 #include <linux/skbuff.h>
+#include <linux/leds.h>
 
 #define SDIO_CLASS_BT_AMP      0x09    /* Type-A Bluetooth AMP interface */
 
@@ -93,6 +94,18 @@ int genl_unregister_family(struct genl_family *family);
 #define genl_register_mc_group(_fam, _grp) genl_register_mc_group(&(_fam)->family, _grp)
 #define genl_unregister_mc_group(_fam, _grp) genl_unregister_mc_group(&(_fam)->family, _grp)
 
+
+extern void led_blink_set(struct led_classdev *led_cdev,
+                         unsigned long *delay_on,
+                         unsigned long *delay_off);
+
+#define led_classdev_unregister compat_led_classdev_unregister
+extern void compat_led_classdev_unregister(struct led_classdev *led_cdev);
+
+#define led_brightness_set compat_led_brightness_set
+extern void compat_led_brightness_set(struct led_classdev *led_cdev,
+                                     enum led_brightness brightness);
+
 #endif /* (LINUX_VERSION_CODE < KERNEL_VERSION(2,6,37)) */
 
 #endif /* LINUX_26_37_COMPAT_H */