2019-04-24 19:06:34

by Matt Redfearn

[permalink] [raw]
Subject: [PATCH] drm/bridge: adv7511: Fix low refresh rate selection

The driver currently sets register 0xfb (Low Refresh Rate) based on the
value of mode->vrefresh. Firstly, this field is specified to be in Hz,
but the magic numbers used by the code are Hz * 1000. This essentially
leads to the low refresh rate always being set to 0x01, since the
vrefresh value will always be less than 24000. Fix the magic numbers to
be in Hz.
Secondly, according to the comment in drm_modes.h, the field is not
supposed to be used in a functional way anyway. Instead, use the helper
function drm_mode_vrefresh().

Fixes: 9c8af882bf12 ("drm: Add adv7511 encoder driver")
Signed-off-by: Matt Redfearn <[email protected]>

---

drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
index 85c2d407a52..e7ddd3e3db9 100644
--- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
+++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
@@ -747,11 +747,11 @@ static void adv7511_mode_set(struct adv7511 *adv7511,
vsync_polarity = 1;
}

- if (mode->vrefresh <= 24000)
+ if (drm_mode_vrefresh(mode) <= 24)
low_refresh_rate = ADV7511_LOW_REFRESH_RATE_24HZ;
- else if (mode->vrefresh <= 25000)
+ else if (drm_mode_vrefresh(mode) <= 25)
low_refresh_rate = ADV7511_LOW_REFRESH_RATE_25HZ;
- else if (mode->vrefresh <= 30000)
+ else if (drm_mode_vrefresh(mode) <= 30)
low_refresh_rate = ADV7511_LOW_REFRESH_RATE_30HZ;
else
low_refresh_rate = ADV7511_LOW_REFRESH_RATE_NONE;
--
2.17.1


2019-05-11 19:33:50

by Laurent Pinchart

[permalink] [raw]
Subject: Re: [PATCH] drm/bridge: adv7511: Fix low refresh rate selection

Hi Matt,

Thank you for the patch.

On Wed, Apr 24, 2019 at 01:22:27PM +0000, Matt Redfearn wrote:
> The driver currently sets register 0xfb (Low Refresh Rate) based on the
> value of mode->vrefresh. Firstly, this field is specified to be in Hz,
> but the magic numbers used by the code are Hz * 1000. This essentially
> leads to the low refresh rate always being set to 0x01, since the
> vrefresh value will always be less than 24000. Fix the magic numbers to
> be in Hz.
> Secondly, according to the comment in drm_modes.h, the field is not
> supposed to be used in a functional way anyway. Instead, use the helper
> function drm_mode_vrefresh().
>
> Fixes: 9c8af882bf12 ("drm: Add adv7511 encoder driver")
> Signed-off-by: Matt Redfearn <[email protected]>

Wow, a 4.5 year old bug fix, nice :-)

Reviewed-by: Laurent Pinchart <[email protected]>

> ---
>
> drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
> index 85c2d407a52..e7ddd3e3db9 100644
> --- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
> +++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
> @@ -747,11 +747,11 @@ static void adv7511_mode_set(struct adv7511 *adv7511,
> vsync_polarity = 1;
> }
>
> - if (mode->vrefresh <= 24000)
> + if (drm_mode_vrefresh(mode) <= 24)
> low_refresh_rate = ADV7511_LOW_REFRESH_RATE_24HZ;
> - else if (mode->vrefresh <= 25000)
> + else if (drm_mode_vrefresh(mode) <= 25)
> low_refresh_rate = ADV7511_LOW_REFRESH_RATE_25HZ;
> - else if (mode->vrefresh <= 30000)
> + else if (drm_mode_vrefresh(mode) <= 30)
> low_refresh_rate = ADV7511_LOW_REFRESH_RATE_30HZ;
> else
> low_refresh_rate = ADV7511_LOW_REFRESH_RATE_NONE;

--
Regards,

Laurent Pinchart

2019-05-14 18:15:02

by Sean Paul

[permalink] [raw]
Subject: Re: [PATCH] drm/bridge: adv7511: Fix low refresh rate selection

On Sat, May 11, 2019 at 10:32:26PM +0300, Laurent Pinchart wrote:
> Hi Matt,
>
> Thank you for the patch.
>
> On Wed, Apr 24, 2019 at 01:22:27PM +0000, Matt Redfearn wrote:
> > The driver currently sets register 0xfb (Low Refresh Rate) based on the
> > value of mode->vrefresh. Firstly, this field is specified to be in Hz,
> > but the magic numbers used by the code are Hz * 1000. This essentially
> > leads to the low refresh rate always being set to 0x01, since the
> > vrefresh value will always be less than 24000. Fix the magic numbers to
> > be in Hz.
> > Secondly, according to the comment in drm_modes.h, the field is not
> > supposed to be used in a functional way anyway. Instead, use the helper
> > function drm_mode_vrefresh().
> >
> > Fixes: 9c8af882bf12 ("drm: Add adv7511 encoder driver")
> > Signed-off-by: Matt Redfearn <[email protected]>
>
> Wow, a 4.5 year old bug fix, nice :-)
>
> Reviewed-by: Laurent Pinchart <[email protected]>
>

Applied to drm-misc-next-fixes.

Thanks!

Sean

> > ---
> >
> > drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 6 +++---
> > 1 file changed, 3 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
> > index 85c2d407a52..e7ddd3e3db9 100644
> > --- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
> > +++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
> > @@ -747,11 +747,11 @@ static void adv7511_mode_set(struct adv7511 *adv7511,
> > vsync_polarity = 1;
> > }
> >
> > - if (mode->vrefresh <= 24000)
> > + if (drm_mode_vrefresh(mode) <= 24)
> > low_refresh_rate = ADV7511_LOW_REFRESH_RATE_24HZ;
> > - else if (mode->vrefresh <= 25000)
> > + else if (drm_mode_vrefresh(mode) <= 25)
> > low_refresh_rate = ADV7511_LOW_REFRESH_RATE_25HZ;
> > - else if (mode->vrefresh <= 30000)
> > + else if (drm_mode_vrefresh(mode) <= 30)
> > low_refresh_rate = ADV7511_LOW_REFRESH_RATE_30HZ;
> > else
> > low_refresh_rate = ADV7511_LOW_REFRESH_RATE_NONE;
>
> --
> Regards,
>
> Laurent Pinchart
> _______________________________________________
> dri-devel mailing list
> [email protected]
> https://lists.freedesktop.org/mailman/listinfo/dri-devel

--
Sean Paul, Software Engineer, Google / Chromium OS