| Message ID | 20190930103840.18970-8-tomi.valkeinen@ti.com |
|---|---|
| State | Accepted |
| Commit | bebf00512cc2c2a942a6dc47674bf44b7a3cb681 |
| Headers | show |
| Series | drm/omap: misc improvements | expand |
Hi Tomi, Thank you for the patch. On Mon, Sep 30, 2019 at 01:38:40PM +0300, Tomi Valkeinen wrote: > If use_mclk is false, mclk_mode is written to a register without > initialization. This doesn't cause any ill effects as the written value > is not used when use_mclk is false. > > To fix this, write use_mclk only when use_mclk is true. > > Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> > --- > drivers/gpu/drm/omapdrm/dss/hdmi4_core.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/omapdrm/dss/hdmi4_core.c b/drivers/gpu/drm/omapdrm/dss/hdmi4_core.c > index 5d5d5588ebc1..c4ffe96e28bc 100644 > --- a/drivers/gpu/drm/omapdrm/dss/hdmi4_core.c > +++ b/drivers/gpu/drm/omapdrm/dss/hdmi4_core.c > @@ -542,8 +542,9 @@ static void hdmi_core_audio_config(struct hdmi_core_data *core, > } > > /* Set ACR clock divisor */ > - REG_FLD_MOD(av_base, > - HDMI_CORE_AV_FREQ_SVAL, cfg->mclk_mode, 2, 0); > + if (cfg->use_mclk) > + REG_FLD_MOD(av_base, HDMI_CORE_AV_FREQ_SVAL, > + cfg->mclk_mode, 2, 0); > > r = hdmi_read_reg(av_base, HDMI_CORE_AV_ACR_CTRL); > /*
On 08/10/2019 17:21, Tony Lindgren wrote: > * Tomi Valkeinen <tomi.valkeinen@ti.com> [191008 14:17]: >> On 08/10/2019 17:13, Tony Lindgren wrote: >>> * Tomi Valkeinen <tomi.valkeinen@ti.com> [190930 10:38]: >>>> If use_mclk is false, mclk_mode is written to a register without >>>> initialization. This doesn't cause any ill effects as the written value >>>> is not used when use_mclk is false. >>>> >>>> To fix this, write use_mclk only when use_mclk is true. >>> >>> Hey nice catch. Based on a quick test looks like this fixes an >>> issue where power consumption stays higher after using HDMI. >>> >>> Would be nice to have merged in the v5.4-rc series: >>> >>> Tested-by: Tony Lindgren <tony@atomide.com> >> >> Really? Ok, well, then it was a good random find =). > > Yeah so it seems :) Earlier I thought there's still some > clkctrl setting wrong after using HDMI, but did not see > anything diffing the clkctrl registers before and after > and gave up. > >> I did already push this to drm-misc-next, as I thought it does not have any >> real effect. I'll check if it's ok to push to drm-misc-fixes too, with Cc >> stable. > > OK great thanks. Pushing this to fixes too would cause conflicts, so we shouldn't push without good reason. How much power saving you see? I think this can still be sent to stable later, after it has been merged to mainline. Tomi
diff --git a/drivers/gpu/drm/omapdrm/dss/hdmi4_core.c b/drivers/gpu/drm/omapdrm/dss/hdmi4_core.c index 5d5d5588ebc1..c4ffe96e28bc 100644 --- a/drivers/gpu/drm/omapdrm/dss/hdmi4_core.c +++ b/drivers/gpu/drm/omapdrm/dss/hdmi4_core.c @@ -542,8 +542,9 @@ static void hdmi_core_audio_config(struct hdmi_core_data *core, } /* Set ACR clock divisor */ - REG_FLD_MOD(av_base, - HDMI_CORE_AV_FREQ_SVAL, cfg->mclk_mode, 2, 0); + if (cfg->use_mclk) + REG_FLD_MOD(av_base, HDMI_CORE_AV_FREQ_SVAL, + cfg->mclk_mode, 2, 0); r = hdmi_read_reg(av_base, HDMI_CORE_AV_ACR_CTRL); /*
If use_mclk is false, mclk_mode is written to a register without initialization. This doesn't cause any ill effects as the written value is not used when use_mclk is false. To fix this, write use_mclk only when use_mclk is true. Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com> --- drivers/gpu/drm/omapdrm/dss/hdmi4_core.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)