[RFC PATCH v2 07/10] block: Add sysfs attributes to LEDs associated with blkdev trigger
From: Ian Pilcher <hidden>
Date: 2021-08-09 03:33:14
Also in:
linux-block, linux-leds, lkml
Subsystem:
block layer, the rest · Maintainers:
Jens Axboe, Linus Torvalds
Add blink_on & blink_off attributes to control the duration of each LED blink (blink_on) and the minimum time between blinks (blink_off) in milliseconds Signed-off-by: Ian Pilcher <redacted> --- block/blk-ledtrig.c | 63 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 63 insertions(+)
diff --git a/block/blk-ledtrig.c b/block/blk-ledtrig.c
index f8cb6de203f8..d02f32205985 100644
--- a/block/blk-ledtrig.c
+++ b/block/blk-ledtrig.c@@ -343,3 +343,66 @@ static void blk_ledtrig_deactivate(struct led_classdev *const led) synchronize_rcu(); kfree(bd_led); } + + +/* + * + * Per-LED blink_on & blink_off device attributes + * + */ + +static ssize_t blk_ledtrig_blink_show(struct device *const dev, + struct device_attribute *const attr, + char *const buf); + +static ssize_t blk_ledtrig_blink_store(struct device *const dev, + struct device_attribute *const attr, + const char *const buf, + const size_t count); + +static struct device_attribute blk_ledtrig_attr_blink_on = + __ATTR(blink_on, 0644, + blk_ledtrig_blink_show, blk_ledtrig_blink_store); + +static struct device_attribute blk_ledtrig_attr_blink_off = + __ATTR(blink_off, 0644, + blk_ledtrig_blink_show, blk_ledtrig_blink_store); + +static ssize_t blk_ledtrig_blink_show(struct device *const dev, + struct device_attribute *const attr, + char *const buf) +{ + struct blk_ledtrig_led *const bd_led = led_trigger_get_drvdata(dev); + unsigned int value; + + if (attr == &blk_ledtrig_attr_blink_on) + value = READ_ONCE(bd_led->blink_on); + else // attr == &blk_ledtrig_attr_blink_off + value = READ_ONCE(bd_led->blink_off); + + return sprintf(buf, "%u\n", value); +} + +static ssize_t blk_ledtrig_blink_store(struct device *const dev, + struct device_attribute *const attr, + const char *const buf, + const size_t count) +{ + struct blk_ledtrig_led *const bd_led = led_trigger_get_drvdata(dev); + unsigned int value; + int ret; + + ret = kstrtouint(buf, 0, &value); + if (ret != 0) + return ret; + + if (value > BLK_LEDTRIG_BLINK_MAX) + return -ERANGE; + + if (attr == &blk_ledtrig_attr_blink_on) + WRITE_ONCE(bd_led->blink_on, value); + else // attr == &blk_ledtrig_attr_blink_off + WRITE_ONCE(bd_led->blink_off, value); + + return count; +}
--
2.31.1
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