]> git.baikalelectronics.ru Git - kernel.git/commit
Revert "pwm: Let pwm_get_state() return the last implemented state"
authorThierry Reding <thierry.reding@gmail.com>
Mon, 21 Oct 2019 10:41:40 +0000 (12:41 +0200)
committerThierry Reding <thierry.reding@gmail.com>
Mon, 21 Oct 2019 14:48:52 +0000 (16:48 +0200)
commitbd5e07695cddc50c2684b9afca3517e30b3f275a
treebaaaa4663cce1e5f33560d4d53e296f8e97dee95
parent83b4b06b7408ce798a220098fbeac6cb0a1db352
Revert "pwm: Let pwm_get_state() return the last implemented state"

It turns out that commit 4c7341e2fbff ("pwm: Let pwm_get_state() return
the last implemented state") causes backlight failures on a number of
boards. The reason is that some of the drivers do not write the full
state through to the hardware registers, which means that ->get_state()
subsequently does not return the correct state. Consumers which rely on
pwm_get_state() returning the current state will therefore get confused
and subsequently try to program a bad state.

Before this change can be made, existing drivers need to be more
carefully audited and fixed to behave as the framework expects. Until
then, keep the original behaviour of returning the software state that
was applied rather than reading the state back from hardware.

Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Tested-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Tested-by: Michal Vokáč <michal.vokac@ysoft.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
drivers/pwm/core.c