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authorSascha Hauer <s.hauer@pengutronix.de>2019-04-05 14:51:50 +0200
committerSascha Hauer <s.hauer@pengutronix.de>2019-04-08 10:16:55 +0200
commit1dc748b3b202cadf9b799874d9af8d441ee556bc (patch)
tree58fd3c90a40e2d0128b0c7f36d63d7fc126bb20d /dts/Bindings/leds
parent9688b49cd3bc0b61a019e8e1311236c9975a0777 (diff)
downloadbarebox-1dc748b3b202cadf9b799874d9af8d441ee556bc.tar.gz
barebox-1dc748b3b202cadf9b799874d9af8d441ee556bc.tar.xz
dts: update to v5.1-rc1
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Diffstat (limited to 'dts/Bindings/leds')
-rw-r--r--dts/Bindings/leds/common.txt12
-rw-r--r--dts/Bindings/leds/leds-trigger-pattern.txt49
2 files changed, 61 insertions, 0 deletions
diff --git a/dts/Bindings/leds/common.txt b/dts/Bindings/leds/common.txt
index aa1399814..70876ac11 100644
--- a/dts/Bindings/leds/common.txt
+++ b/dts/Bindings/leds/common.txt
@@ -37,6 +37,18 @@ Optional properties for child nodes:
"ide-disk" - LED indicates IDE disk activity (deprecated),
in new implementations use "disk-activity"
"timer" - LED flashes at a fixed, configurable rate
+ "pattern" - LED alters the brightness for the specified duration with one
+ software timer (requires "led-pattern" property)
+
+- led-pattern : Array of integers with default pattern for certain triggers.
+ Each trigger may parse this property differently:
+ - one-shot : two numbers specifying delay on and delay off (in ms),
+ - timer : two numbers specifying delay on and delay off (in ms),
+ - pattern : the pattern is given by a series of tuples, of
+ brightness and duration (in ms). The exact format is
+ described in:
+ Documentation/devicetree/bindings/leds/leds-trigger-pattern.txt
+
- led-max-microamp : Maximum LED supply current in microamperes. This property
can be made mandatory for the board configurations
diff --git a/dts/Bindings/leds/leds-trigger-pattern.txt b/dts/Bindings/leds/leds-trigger-pattern.txt
new file mode 100644
index 000000000..d3696680b
--- /dev/null
+++ b/dts/Bindings/leds/leds-trigger-pattern.txt
@@ -0,0 +1,49 @@
+* Pattern format for LED pattern trigger
+
+The pattern is given by a series of tuples, of brightness and duration (ms).
+The LED is expected to traverse the series and each brightness value for the
+specified duration. Duration of 0 means brightness should immediately change to
+new value, and writing malformed pattern deactivates any active one.
+
+1. For gradual dimming, the dimming interval now is set as 50 milliseconds. So
+the tuple with duration less than dimming interval (50ms) is treated as a step
+change of brightness, i.e. the subsequent brightness will be applied without
+adding intervening dimming intervals.
+
+The gradual dimming format of the software pattern values should be:
+"brightness_1 duration_1 brightness_2 duration_2 brightness_3 duration_3 ...".
+For example (using sysfs interface):
+
+echo 0 1000 255 2000 > pattern
+
+It will make the LED go gradually from zero-intensity to max (255) intensity in
+1000 milliseconds, then back to zero intensity in 2000 milliseconds:
+
+LED brightness
+ ^
+255-| / \ / \ /
+ | / \ / \ /
+ | / \ / \ /
+ | / \ / \ /
+ 0-| / \/ \/
+ +---0----1----2----3----4----5----6------------> time (s)
+
+2. To make the LED go instantly from one brightness value to another, we should
+use zero-time lengths (the brightness must be same as the previous tuple's). So
+the format should be: "brightness_1 duration_1 brightness_1 0 brightness_2
+duration_2 brightness_2 0 ...".
+For example (using sysfs interface):
+
+echo 0 1000 0 0 255 2000 255 0 > pattern
+
+It will make the LED stay off for one second, then stay at max brightness for
+two seconds:
+
+LED brightness
+ ^
+255-| +---------+ +---------+
+ | | | | |
+ | | | | |
+ | | | | |
+ 0-| -----+ +----+ +----
+ +---0----1----2----3----4----5----6------------> time (s)