path: root/Documentation/leds
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authorKim, Milo <Milo.Kim@ti.com>2012-03-23 15:02:09 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2012-03-23 16:58:34 -0700
commit011af7bc7cd188a0310e2d26cdc2cc5d90148b0c (patch)
tree3f3aa08b555bdcb4c4dfe6e8d4bec9c4205ccd79 /Documentation/leds
parent3b49aacd0e56d5bf1b511f6554f17cd65eb8da64 (diff)
drivers/leds/leds-lp5521.c: support led pattern data
The lp5521 has autonomous operation mode without external control. Using lp5521_platform_data, various led patterns can be configurable. For supporting this feature, new functions and device attribute are added. Structure of lp5521_led_pattern: 3 channels are supported - red, green and blue. Pattern(s) of each channel and numbers of pattern(s) are defined in the pla= tform data. Pattern data are hexa codes which include pattern commands such like set pwm, wait, ramp up/down, branch and so on. Pattern mode functions: * lp5521_clear_program_memory Before running new led pattern, program memory should be cleared. * lp5521_write_program_memory Pattern data updated in the program memory via the i2c. * lp5521_get_pattern Get pattern from predefined in the platform data. * lp5521_run_led_pattern Stop current pattern or run new pattern. Transition time is required between different operation mode. Device attribute - 'led_pattern': To load specific led pattern, new device attribute is added. When the lp5521 driver is unloaded, stop current led pattern mode. Documentation updated : description about how to define the led patterns and example. [akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Cc: Arun MURTHY <arun.murthy@stericsson.com> Cc: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com> Cc: Richard Purdie <rpurdie@rpsys.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'Documentation/leds')
1 files changed, 38 insertions, 0 deletions
diff --git a/Documentation/leds/leds-lp5521.txt b/Documentation/leds/leds-lp5521.txt
index e3c66c64591..0e542ab3d4a 100644
--- a/Documentation/leds/leds-lp5521.txt
+++ b/Documentation/leds/leds-lp5521.txt
@@ -111,3 +111,41 @@ static struct lp5521_platform_data lp5521_pdata = {
.clock_mode = LP5521_CLOCK_INT,
.update_config = LP5521_CONFIGS,
+LED patterns : LP5521 has autonomous operation without external control.
+Pattern data can be defined in the platform data.
+example of led pattern data :
+/* RGB(50,5,0) 500ms on, 500ms off, infinite loop */
+static u8 pattern_red[] = {
+ 0x40, 0x32, 0x60, 0x00, 0x40, 0x00, 0x60, 0x00,
+ };
+static u8 pattern_green[] = {
+ 0x40, 0x05, 0x60, 0x00, 0x40, 0x00, 0x60, 0x00,
+ };
+static struct lp5521_led_pattern board_led_patterns[] = {
+ {
+ .r = pattern_red,
+ .g = pattern_green,
+ .size_r = ARRAY_SIZE(pattern_red),
+ .size_g = ARRAY_SIZE(pattern_green),
+ },
+static struct lp5521_platform_data lp5521_platform_data = {
+ .led_config = lp5521_led_config,
+ .num_channels = ARRAY_SIZE(lp5521_led_config),
+ .clock_mode = LP5521_CLOCK_EXT,
+ .patterns = board_led_patterns,
+ .num_patterns = ARRAY_SIZE(board_led_patterns),
+Then predefined led pattern(s) can be executed via the sysfs.
+To start the pattern #1,
+# echo 1 > /sys/bus/i2c/devices/xxxx/led_pattern
+(xxxx : i2c bus & slave address)
+To end the pattern,
+# echo 0 > /sys/bus/i2c/devices/xxxx/led_pattern