leds: st1202: Disable channel when brightness is set to zero

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When brightness_set() is called with LED_OFF, only the ILED register is
zeroed; the channel enable bit is left set from probe time. A hardware
channel enabled with ILED=0 still draws a small residual current, causing
a dim glow even when the LED is supposed to be off.

Fix this by splitting st1202_channel_set() into a lockless inner function
__st1202_channel_set() and a locking wrapper, then calling the inner
function from brightness_set() while it already holds the mutex. The
channel is now disabled when value is zero and re-enabled when non-zero,
in the same lock region as the ILED write.

Fixes: 259230378c ("leds: Add LED1202 I2C driver")
Signed-off-by: Manuel Fombuena <fombuena@outlook.com>
Assisted-by: Claude:claude-sonnet-4-6
Link: https://patch.msgid.link/GV1PR08MB8497F11B30FE7D74CAA25135C5F52@GV1PR08MB8497.eurprd08.prod.outlook.com
Signed-off-by: Lee Jones <lee@kernel.org>

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Manuel Fombuena 2026-07-02 23:34:37 +01:00 • committed by Lee Jones

parent 7cbe470366

commit 0767335233

1 changed files with 39 additions and 29 deletions

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drivers/leds/leds-st1202.c

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