From: Ian Pilcher <arequipeno@gmail.com>
To: linux-block@vger.kernel.org, linux-leds@vger.kernel.org
Cc: axboe@kernel.dk, pavel@ucw.cz, kabel@kernel.org,
linux-kernel@vger.kernel.org, kernelnewbies@kernelnewbies.org
Subject: [RFC PATCH v3 12/18] ledtrig-blkdev: Add sysfs attributes to [dis]associate LEDs & devices
Date: Wed, 18 Aug 2021 21:50:47 -0500 [thread overview]
Message-ID: <20210819025053.222710-13-arequipeno@gmail.com> (raw)
In-Reply-To: <20210819025053.222710-1-arequipeno@gmail.com>
/sys/class/leds/<led>/add_blkdev - to create device/LED associations
/sys/class/leds/<led>/delete_blkdev to remove device/LED associations
For both attributes, accept multiple device names separated by whitespace
Signed-off-by: Ian Pilcher <arequipeno@gmail.com>
---
drivers/leds/trigger/ledtrig-blkdev.c | 48 +++++++++++++++++++++++++++
1 file changed, 48 insertions(+)
diff --git a/drivers/leds/trigger/ledtrig-blkdev.c b/drivers/leds/trigger/ledtrig-blkdev.c
index a1646752b9a0..15b15aefdfd8 100644
--- a/drivers/leds/trigger/ledtrig-blkdev.c
+++ b/drivers/leds/trigger/ledtrig-blkdev.c
@@ -480,3 +480,51 @@ static int blkdev_disk_add(struct ledtrig_blkdev_led *const led,
exit_return:
return ret;
}
+
+
+/*
+ *
+ * sysfs attributes to add & delete devices from LEDs
+ *
+ */
+
+static ssize_t blkdev_add_or_del(struct device *const dev,
+ struct device_attribute *const attr,
+ const char *const buf, const size_t count);
+
+static struct device_attribute ledtrig_blkdev_attr_add =
+ __ATTR(add_blkdev, 0200, NULL, blkdev_add_or_del);
+
+static struct device_attribute ledtrig_blkdev_attr_del =
+ __ATTR(delete_blkdev, 0200, NULL, blkdev_add_or_del);
+
+static ssize_t blkdev_add_or_del(struct device *const dev,
+ struct device_attribute *const attr,
+ const char *const buf, const size_t count)
+{
+ struct ledtrig_blkdev_led *const led = led_trigger_get_drvdata(dev);
+ const char *const disk_name = blkdev_skip_space(buf);
+ const char *const endp = blkdev_find_space(disk_name);
+ const ptrdiff_t name_len = endp - disk_name; /* always >= 0 */
+ int ret;
+
+ if (name_len == 0) {
+ pr_info("blkdev LED: empty block device name\n");
+ return -EINVAL;
+ }
+
+ if (attr == &ledtrig_blkdev_attr_del) {
+ blkdev_disk_delete(led, disk_name, name_len);
+ } else { /* attr == &ledtrig_blkdev_attr_add */
+ ret = blkdev_disk_add(led, disk_name, name_len);
+ if (ret != 0)
+ return ret;
+ }
+
+ /*
+ * Consume everything up to the next non-whitespace token (or the end
+ * of the input). Avoids "empty block device name" error if there is
+ * whitespace after the last token (e.g. a newline).
+ */
+ return blkdev_skip_space(endp) - buf;
+}
--
2.31.1
next prev parent reply other threads:[~2021-08-19 2:51 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-08-19 2:50 [RFC PATCH v3 00/18] Add block device LED trigger Ian Pilcher
2021-08-19 2:50 ` [RFC PATCH v3 01/18] docs: Add block device (blkdev) LED trigger documentation Ian Pilcher
2021-08-19 2:50 ` [RFC PATCH v3 02/18] block: Add get_disk_by_name() for use by blkdev LED trigger Ian Pilcher
2021-08-19 2:50 ` [RFC PATCH v3 03/18] ledtrig-blkdev: Add file (ledtrig-blkdev.c) for block device " Ian Pilcher
2021-08-19 2:50 ` [RFC PATCH v3 04/18] ledtrig-blkdev: Add misc. helper functions to blkdev " Ian Pilcher
2021-08-19 2:50 ` [RFC PATCH v3 05/18] ledtrig-blkdev: Periodically check devices for activity & blink LEDs Ian Pilcher
2021-08-19 2:50 ` [RFC PATCH v3 06/18] block: Add LED trigger pointer to struct gendisk Ian Pilcher
2021-08-19 2:50 ` [RFC PATCH v3 07/18] ledtrig-blkdev: Add function to initialize gendisk ledtrig member Ian Pilcher
2021-08-19 2:50 ` [RFC PATCH v3 08/18] ledtrig-blkdev: Add function to remove LED/device association Ian Pilcher
2021-08-19 2:50 ` [RFC PATCH v3 09/18] ledtrig-blkdev: Add function to disassociate a device from all LEDs Ian Pilcher
2021-08-19 2:50 ` [RFC PATCH v3 10/18] block: Call LED trigger init/cleanup functions Ian Pilcher
2021-08-19 2:50 ` [RFC PATCH v3 11/18] ledtrig-blkdev: Add function to associate a device with an LED Ian Pilcher
2021-08-19 2:50 ` Ian Pilcher [this message]
2021-08-19 2:50 ` [RFC PATCH v3 13/18] ledtrig-blkdev: Add blink_time & interval sysfs attributes Ian Pilcher
2021-08-19 2:50 ` [RFC PATCH v3 14/18] ledtrig-blkdev: Add mode (read/write/rw) sysfs attributue Ian Pilcher
2021-08-19 2:50 ` [RFC PATCH v3 15/18] ledtrig-blkdev: Add function to associate blkdev trigger with LED Ian Pilcher
2021-08-19 2:50 ` [RFC PATCH v3 16/18] ledtrig-blkdev: Add function to disassociate an LED from the trigger Ian Pilcher
2021-08-19 2:50 ` [RFC PATCH v3 17/18] ledtrig-blkdev: Add initialization function Ian Pilcher
2021-08-19 2:50 ` [RFC PATCH v3 18/18] ledtrig-blkdev: Add config option to enable the trigger Ian Pilcher
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