[PATCH 10/18] ledtrig-blkdev: Add function to associate the trigger with an LED

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Allocate per-LED data structure and initialize with default values

Create /sys/class/leds/<led>/block_devices directory

Increment module reference count.  Module can only be removed when no LEDs
are associated with the trigger.

Signed-off-by: Ian Pilcher <arequipeno@xxxxxxxxx>
---
 drivers/leds/trigger/ledtrig-blkdev.c | 54 +++++++++++++++++++++++++++
 1 file changed, 54 insertions(+)

diff --git a/drivers/leds/trigger/ledtrig-blkdev.c b/drivers/leds/trigger/ledtrig-blkdev.c
index 37ba9bb3542e..bbf71ff18057 100644
--- a/drivers/leds/trigger/ledtrig-blkdev.c
+++ b/drivers/leds/trigger/ledtrig-blkdev.c
@@ -198,3 +198,57 @@ static void blkdev_process(struct work_struct *const work)
 	delay = READ_ONCE(ledtrig_blkdev_interval);
 	WARN_ON_ONCE(!schedule_delayed_work(&ledtrig_blkdev_work, delay));
 }
+
+
+/*
+ *
+ *	Associate an LED with the blkdev trigger
+ *
+ */
+
+static int blkdev_activate(struct led_classdev *const led_dev)
+{
+	struct ledtrig_blkdev_led *led;
+	int ret;
+
+	if (WARN_ON(!try_module_get(THIS_MODULE))) {
+		ret = -ENODEV;		/* -ESHOULDNEVERHAPPEN */
+		goto exit_return;
+	}
+
+	led = kmalloc(sizeof(*led), GFP_KERNEL);
+	if (led == NULL) {
+		ret = -ENOMEM;
+		goto exit_put_module;
+	}
+
+	led->led_dev = led_dev;
+	led->blink_msec = LEDTRIG_BLKDEV_BLINK_MSEC;
+	led->mode = LEDTRIG_BLKDEV_MODE_RW;
+	INIT_HLIST_HEAD(&led->disks);
+
+	ret = mutex_lock_interruptible(&ledtrig_blkdev_mutex);
+	if (ret != 0)
+		goto exit_free;
+
+	led->dir = kobject_create_and_add("block_devices", &led_dev->dev->kobj);
+	if (led->dir == NULL) {
+		ret = -ENOMEM;
+		goto exit_unlock;
+	}
+
+	hlist_add_head(&led->leds_node, &ledtrig_blkdev_leds);
+	led_set_trigger_data(led_dev, led);
+	ret = 0;
+
+exit_unlock:
+	mutex_unlock(&ledtrig_blkdev_mutex);
+exit_free:
+	if (ret != 0)
+		kfree(led);
+exit_put_module:
+	if (ret != 0)
+		module_put(THIS_MODULE);
+exit_return:
+	return ret;
+}
-- 
2.31.1




[Index of Archives]     [Linux ARM Kernel]     [Linux ARM]     [Linux Omap]     [Fedora ARM]     [IETF Annouce]     [Security]     [Bugtraq]     [Linux OMAP]     [Linux MIPS]     [ECOS]     [Asterisk Internet PBX]     [Linux API]

  Powered by Linux