| Message ID | 20190527102616.28315-1-vivek.gautam@codeaurora.org (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
| Series | [1/1] drm/panel: truly: Add additional delay after pulling down reset gpio | expand |
On 27/05/2019 12:26, Vivek Gautam wrote: > MTP SDM845 panel seems to need additional delay to bring panel > to a workable state. Running modetest without this change displays > blurry artifacts. > > Signed-off-by: Vivek Gautam <vivek.gautam@codeaurora.org> > --- > drivers/gpu/drm/panel/panel-truly-nt35597.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/gpu/drm/panel/panel-truly-nt35597.c b/drivers/gpu/drm/panel/panel-truly-nt35597.c > index fc2a66c53db4..aa7153fd3be4 100644 > --- a/drivers/gpu/drm/panel/panel-truly-nt35597.c > +++ b/drivers/gpu/drm/panel/panel-truly-nt35597.c > @@ -280,6 +280,7 @@ static int truly_35597_power_on(struct truly_nt35597 *ctx) > gpiod_set_value(ctx->reset_gpio, 1); > usleep_range(10000, 20000); > gpiod_set_value(ctx->reset_gpio, 0); > + usleep_range(10000, 20000); I'm not sure usleep_range() makes sense with these values. AFAIU, usleep_range() is typically used for sub-jiffy sleeps, and is based on HRT to generate an interrupt. Once we get into jiffy granularity, it seems to me msleep() is good enough. IIUC, it would piggy-back on the jiffy timer interrupt. In short, why not just use msleep(10); ? Regards.
On 5/28/2019 2:13 PM, Marc Gonzalez wrote: > On 27/05/2019 12:26, Vivek Gautam wrote: > >> MTP SDM845 panel seems to need additional delay to bring panel >> to a workable state. Running modetest without this change displays >> blurry artifacts. >> >> Signed-off-by: Vivek Gautam <vivek.gautam@codeaurora.org> >> --- >> drivers/gpu/drm/panel/panel-truly-nt35597.c | 1 + >> 1 file changed, 1 insertion(+) >> >> diff --git a/drivers/gpu/drm/panel/panel-truly-nt35597.c b/drivers/gpu/drm/panel/panel-truly-nt35597.c >> index fc2a66c53db4..aa7153fd3be4 100644 >> --- a/drivers/gpu/drm/panel/panel-truly-nt35597.c >> +++ b/drivers/gpu/drm/panel/panel-truly-nt35597.c >> @@ -280,6 +280,7 @@ static int truly_35597_power_on(struct truly_nt35597 *ctx) >> gpiod_set_value(ctx->reset_gpio, 1); >> usleep_range(10000, 20000); >> gpiod_set_value(ctx->reset_gpio, 0); >> + usleep_range(10000, 20000); > I'm not sure usleep_range() makes sense with these values. > > AFAIU, usleep_range() is typically used for sub-jiffy sleeps, and is based > on HRT to generate an interrupt. > > Once we get into jiffy granularity, it seems to me msleep() is good enough. > IIUC, it would piggy-back on the jiffy timer interrupt. > > In short, why not just use msleep(10); ? I am just maintaining the symmetry across older code. Thanks Vivek > > Regards.
Hi Vivek, On Mon, May 27, 2019 at 03:56:16PM +0530, Vivek Gautam wrote: > MTP SDM845 panel seems to need additional delay to bring panel > to a workable state. Running modetest without this change displays > blurry artifacts. > > Signed-off-by: Vivek Gautam <vivek.gautam@codeaurora.org> added to drm-misc-next Sam > --- > drivers/gpu/drm/panel/panel-truly-nt35597.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/gpu/drm/panel/panel-truly-nt35597.c b/drivers/gpu/drm/panel/panel-truly-nt35597.c > index fc2a66c53db4..aa7153fd3be4 100644 > --- a/drivers/gpu/drm/panel/panel-truly-nt35597.c > +++ b/drivers/gpu/drm/panel/panel-truly-nt35597.c > @@ -280,6 +280,7 @@ static int truly_35597_power_on(struct truly_nt35597 *ctx) > gpiod_set_value(ctx->reset_gpio, 1); > usleep_range(10000, 20000); > gpiod_set_value(ctx->reset_gpio, 0); > + usleep_range(10000, 20000); > > return 0; > } > -- > QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member > of Code Aurora Forum, hosted by The Linux Foundation > > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel
On Wed, Jun 5, 2019 at 1:54 PM Sam Ravnborg <sam@ravnborg.org> wrote: > > Hi Vivek, > > On Mon, May 27, 2019 at 03:56:16PM +0530, Vivek Gautam wrote: > > MTP SDM845 panel seems to need additional delay to bring panel > > to a workable state. Running modetest without this change displays > > blurry artifacts. > > > > Signed-off-by: Vivek Gautam <vivek.gautam@codeaurora.org> > > added to drm-misc-next Thanks a lot. Best regards Vivek > > Sam > > > --- > > drivers/gpu/drm/panel/panel-truly-nt35597.c | 1 + > > 1 file changed, 1 insertion(+) > > > > diff --git a/drivers/gpu/drm/panel/panel-truly-nt35597.c b/drivers/gpu/drm/panel/panel-truly-nt35597.c > > index fc2a66c53db4..aa7153fd3be4 100644 > > --- a/drivers/gpu/drm/panel/panel-truly-nt35597.c > > +++ b/drivers/gpu/drm/panel/panel-truly-nt35597.c > > @@ -280,6 +280,7 @@ static int truly_35597_power_on(struct truly_nt35597 *ctx) > > gpiod_set_value(ctx->reset_gpio, 1); > > usleep_range(10000, 20000); > > gpiod_set_value(ctx->reset_gpio, 0); > > + usleep_range(10000, 20000); > > > > return 0; > > } > > -- > > QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member > > of Code Aurora Forum, hosted by The Linux Foundation > > > > _______________________________________________ > > dri-devel mailing list > > dri-devel@lists.freedesktop.org > > https://lists.freedesktop.org/mailman/listinfo/dri-devel
diff --git a/drivers/gpu/drm/panel/panel-truly-nt35597.c b/drivers/gpu/drm/panel/panel-truly-nt35597.c index fc2a66c53db4..aa7153fd3be4 100644 --- a/drivers/gpu/drm/panel/panel-truly-nt35597.c +++ b/drivers/gpu/drm/panel/panel-truly-nt35597.c @@ -280,6 +280,7 @@ static int truly_35597_power_on(struct truly_nt35597 *ctx) gpiod_set_value(ctx->reset_gpio, 1); usleep_range(10000, 20000); gpiod_set_value(ctx->reset_gpio, 0); + usleep_range(10000, 20000); return 0; }
MTP SDM845 panel seems to need additional delay to bring panel to a workable state. Running modetest without this change displays blurry artifacts. Signed-off-by: Vivek Gautam <vivek.gautam@codeaurora.org> --- drivers/gpu/drm/panel/panel-truly-nt35597.c | 1 + 1 file changed, 1 insertion(+)