Re: [PATCH 0/2] pwm: meson: two small bug-fixes

From: Thierry Reding
Date: Thu May 09 2019 - 10:54:16 EST


On Mon, Apr 01, 2019 at 08:18:15PM +0200, Martin Blumenstingl wrote:
> This series applies on top of my other fix "pwm: meson: fix scheduling
> while atomic issue" from [0]
>
> The first patch fixes an issue where the maximum possible pre-divider
> (128) could not be used because there was an off-by-one error in the
> code. I discovered this while testing with the longest supported period
> (349514407ns) when running from XTAL. This is verified to work on my
> Meson8b Odroid-C1 board using "pwm_b" on GPIOX_11.
>
> The second patch was suggested by Uwe Kleine-KÃnig but was actually
> implemented much earlier (back in mid 2018) by Bichao Zheng from
> Amlogic. This patch fixes changing the duty cycle by relying on the
> hardware to re-start the PWM output (instead of adding an artificial
> "constant LOW" of about 20ms - as measured by Bichao Zheng when
> stopping and re-starting the PWM output from within the driver). I
> tested this fix on my Meson8b Odroid-C1 board which uses a PWM driven
> CPU regulator (DVFS with all supported OPPs is still working fine for
> me, although I couldn't observe any issues before this patch).
>
> I also have some code-improvements queued which I'll send in the next
> days, see [1]
>
>
> [0] https://patchwork.kernel.org/cover/10880419/
> [1] https://github.com/xdarklight/linux/commits/meson-pwm-for-5.2-v1
>
>
> Bichao Zheng (1):
> pwm: meson: don't disable pwm when setting duty repeatedly
>
> Martin Blumenstingl (1):
> pwm: meson: consider 128 a valid pre-divider
>
> drivers/pwm/pwm-meson.c | 9 ++-------
> 1 file changed, 2 insertions(+), 7 deletions(-)

Both patches applied, thanks.

Thierry

Attachment: signature.asc
Description: PGP signature