/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@xxxxxxxxx>
---
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
