[PATCH v2] pwm: rockchip: Keep enabled PWMs running while probing

[Thierry Reding]

On Sat, Sep 19, 2020 at 03:33:06PM -0400, Simon South wrote:
> Following commit cfc4c189bc70 ("pwm: Read initial hardware state at
> request time") the Rockchip PWM driver can no longer assume a device's
> pwm_state structure has been populated after a call to pwmchip_add().
> Consequently, the test in rockchip_pwm_probe() intended to prevent the
> driver from stopping PWM devices already enabled by the bootloader no
> longer functions reliably and this can lead to the kernel hanging
> during startup, particularly on devices like the Pinebook Pro that use
> a PWM-controlled backlight for their display.
> 
> Avoid this by querying the device directly at probe time to determine
> whether or not it is enabled.
> 
> Fixes: cfc4c189bc70 ("pwm: Read initial hardware state at request time")
> Signed-off-by: Simon South <simon at simonsouth.net>
> ---
>  drivers/pwm/pwm-rockchip.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)

Applied, thanks.

Thierry
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 833 bytes
Desc: not available
URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20200923/24257057/attachment.sig>