From: Ian Pilcher <arequipeno@gmail.com>
To: axboe@kernel.dk, pavel@ucw.cz
Cc: linux-leds@vger.kernel.org, linux-block@vger.kernel.org,
linux@vger.kernel.org, gregkh@linuxfoundation.org,
kabel@kernel.org
Subject: [PATCH 18/18] ledtrig-blkdev: Add initialization & exit functions
Date: Fri, 3 Sep 2021 15:45:48 -0500 [thread overview]
Message-ID: <20210903204548.2745354-19-arequipeno@gmail.com> (raw)
In-Reply-To: <20210903204548.2745354-1-arequipeno@gmail.com>
Init function:
* Initialize interval (convert default value to jiffies)
* Initialize __ledtrig_blkdev_disk_cleanup function pointer
* Register the block device LED trigger
Exit functioon:
* Unregister the LED trigger
* Set __ledtrig_blkdev_disk_cleanup back to NULL
Signed-off-by: Ian Pilcher <arequipeno@gmail.com>
---
drivers/leds/trigger/ledtrig-blkdev.c | 78 +++++++++++++++++++++++++++
1 file changed, 78 insertions(+)
diff --git a/drivers/leds/trigger/ledtrig-blkdev.c b/drivers/leds/trigger/ledtrig-blkdev.c
index ec167633e329..e6ff5baada2e 100644
--- a/drivers/leds/trigger/ledtrig-blkdev.c
+++ b/drivers/leds/trigger/ledtrig-blkdev.c
@@ -687,3 +687,81 @@ static ssize_t blkdev_mode_store(struct device *const dev,
static struct device_attribute ledtrig_blkdev_attr_mode =
__ATTR(mode, 0644, blkdev_mode_show, blkdev_mode_store);
+
+
+/*
+ *
+ * Initialization - register the trigger
+ *
+ */
+
+static struct attribute *ledtrig_blkdev_attrs[] = {
+ &ledtrig_blkdev_attr_add.attr,
+ &ledtrig_blkdev_attr_del.attr,
+ &ledtrig_blkdev_attr_blink_time.attr,
+ &ledtrig_blkdev_attr_interval.attr,
+ &ledtrig_blkdev_attr_mode.attr,
+ NULL
+};
+
+static const struct attribute_group ledtrig_blkdev_attr_group = {
+ .attrs = ledtrig_blkdev_attrs,
+};
+
+static const struct attribute_group *ledtrig_blkdev_attr_groups[] = {
+ &ledtrig_blkdev_attr_group,
+ NULL
+};
+
+static struct led_trigger ledtrig_blkdev_trigger = {
+ .name = "blkdev",
+ .activate = blkdev_activate,
+ .deactivate = blkdev_deactivate,
+ .groups = ledtrig_blkdev_attr_groups,
+};
+
+static int __init blkdev_init(void)
+{
+ int ret;
+
+ ret = mutex_lock_interruptible(&ledtrig_blkdev_mutex);
+ if (ret != 0)
+ return ret;
+
+ ledtrig_blkdev_interval = msecs_to_jiffies(LEDTRIG_BLKDEV_INTERVAL);
+ __ledtrig_blkdev_disk_cleanup = blkdev_disk_cleanup;
+
+ /*
+ * Can't call led_trigger_register() with ledtrig_blkdev_mutex locked.
+ * If an LED has blkdev as its default_trigger, blkdev_activate() will
+ * be called for that LED, and it will try to lock the mutex, which will
+ * hang.
+ */
+ mutex_unlock(&ledtrig_blkdev_mutex);
+
+ ret = led_trigger_register(&ledtrig_blkdev_trigger);
+ if (ret != 0) {
+ mutex_lock(&ledtrig_blkdev_mutex);
+ __ledtrig_blkdev_disk_cleanup = NULL;
+ mutex_unlock(&ledtrig_blkdev_mutex);
+ }
+
+ return ret;
+}
+module_init(blkdev_init);
+
+static void __exit blkdev_exit(void)
+{
+ mutex_lock(&ledtrig_blkdev_mutex);
+
+ /*
+ * It's OK to call led_trigger_unregister() with the mutex locked,
+ * because the module can only be unloaded when no LEDs are using
+ * the blkdev trigger, so blkdev_deactivate() won't be called.
+ */
+ led_trigger_unregister(&ledtrig_blkdev_trigger);
+ __ledtrig_blkdev_disk_cleanup = NULL;
+
+ mutex_unlock(&ledtrig_blkdev_mutex);
+}
+module_exit(blkdev_exit);
--
2.31.1
next prev parent reply other threads:[~2021-09-03 20:46 UTC|newest]
Thread overview: 43+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-09-03 20:45 [PATCH 00/18] Introduce block device LED trigger Ian Pilcher
2021-09-03 20:45 ` [PATCH 01/18] docs: Add block device (blkdev) LED trigger documentation Ian Pilcher
2021-09-04 6:29 ` Pavel Machek
2021-09-05 14:49 ` Ian Pilcher
2021-09-05 18:42 ` Pavel Machek
2021-09-05 23:13 ` Ian Pilcher
2021-09-03 20:45 ` [PATCH 02/18] ledtrig-blkdev: Add build infra for block device LED trigger Ian Pilcher
2021-09-03 20:45 ` [PATCH 03/18] ledtrig-blkdev: Add function placeholders needed by block changes Ian Pilcher
2021-09-04 16:57 ` kernel test robot
2021-09-03 20:45 ` [PATCH 04/18] block: Add block device LED trigger integrations Ian Pilcher
2021-09-03 20:45 ` [PATCH 05/18] ledtrig-blkdev: Implement functions called from block subsystem Ian Pilcher
2021-09-03 20:45 ` [PATCH 06/18] ledtrig-blkdev: Add function to get gendisk by name Ian Pilcher
2021-09-03 20:45 ` [PATCH 07/18] ledtrig-blkdev: Add constants, data types, and global variables Ian Pilcher
2021-09-03 20:45 ` [PATCH 08/18] ledtrig-blkdev: Add miscellaneous helper functions Ian Pilcher
2021-09-04 6:00 ` Greg KH
2021-09-04 22:43 ` Ian Pilcher
2021-09-03 20:45 ` [PATCH 09/18] ledtrig-blkdev: Periodically check devices for activity & blink LEDs Ian Pilcher
2021-09-04 6:01 ` Greg KH
2021-09-05 14:39 ` Ian Pilcher
2021-09-05 14:51 ` Greg KH
2021-09-05 14:56 ` Ian Pilcher
2021-09-05 15:12 ` Greg KH
2021-09-05 16:55 ` Eric Biggers
2021-09-03 20:45 ` [PATCH 10/18] ledtrig-blkdev: Add function to associate the trigger with an LED Ian Pilcher
2021-09-03 20:45 ` [PATCH 11/18] ledtrig-blkdev: Add function to associate a device " Ian Pilcher
2021-09-03 20:45 ` [PATCH 12/18] ledtrig-blkdev: Add function to remove LED/device association Ian Pilcher
2021-09-03 20:45 ` [PATCH 13/18] ledtrig-blkdev: Add function to disassociate a device from all LEDs Ian Pilcher
2021-09-03 20:45 ` [PATCH 14/18] ledtrig-blkdev: Add function to disassociate an LED from the trigger Ian Pilcher
2021-09-03 20:45 ` [PATCH 15/18] ledtrig-blkdev: Add sysfs attributes to [un]link LEDs & devices Ian Pilcher
2021-09-04 5:57 ` Greg KH
2021-09-04 21:28 ` Ian Pilcher
2021-09-04 5:59 ` Greg KH
2021-09-04 22:35 ` Ian Pilcher
2021-09-05 14:51 ` Greg KH
2021-09-05 15:33 ` Ian Pilcher
2021-09-05 16:43 ` Greg KH
2021-09-03 20:45 ` [PATCH 16/18] ledtrig-blkdev: Add blink_time & interval sysfs attributes Ian Pilcher
2021-09-03 20:45 ` [PATCH 17/18] ledtrig-blkdev: Add mode (read/write/rw) sysfs attributue Ian Pilcher
2021-09-04 5:57 ` Greg KH
2021-09-04 21:01 ` Ian Pilcher
2021-09-05 14:50 ` Greg KH
2021-09-03 20:45 ` Ian Pilcher [this message]
2021-09-04 6:35 ` [PATCH 00/18] Introduce block device LED trigger Pavel Machek
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