Re: [PATCH v2 10/13] leds: st1202: Clear unused pattern slots in blink_set()

[sashiko-bot@kernel.org]

> st1202_blink_set() programs slots 0 and 1 of its own channel and leaves
> slots 2 to 7 at ST1202_PATTERN_PWM_FULL, the value both st1202_led_set()
> and st1202_led_pattern_clear() leave behind. Nothing keeps those slots
> out of the output except the duration registers being zero, and those
> are shared by all twelve channels.
> 
> Another channel programming a hardware pattern longer than two steps
> writes those durations again and re-arms the sequencer, so the blinking
> channel drives full scale for the extra steps. With two LEDs on one
> device, blinking one and giving the other a four step pattern, the
> blinking channel lights during the two steps it never programmed.
> 
> Zero the channel's own unused slots, the same invariant
> st1202_led_pattern_set() applies to the slots beyond its pattern length.
> blink_set() already zeroes durations 2 to 7 when it runs; the slots are
> exposed only when another channel sets those shared durations again.
> 
> A channel whose blink is shorter than the active timeline still loses
> its own timing, because the sequencer has one set of duration registers.
> This only stops it emitting output it never asked for.
> 
> Fixes: 35cbd34a6a05 ("leds: st1202: Add hardware-accelerated blink support")
> Signed-off-by: Manuel Fombuena <fombuena@outlook.com>

Sashiko has reviewed this patch and found no issues. It looks great!

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