Re: [PATCH v2] drm/msm/dp: handle irq_hpd with sink_count = 0 correctly

[khsieh]

On 2021-05-12 11:50, Stephen Boyd wrote:
> Quoting Kuogee Hsieh (2021-05-12 10:29:18)
> > irq_hpd interrupt should be handled after dongle plugged in and
> > before dongle unplugged. Hence irq_hpd interrupt is enabled at
> > the end of the plugin handle and disabled at the beginning of
> > unplugged handle. Current irq_hpd with sink_count = 0 is wrongly
> > handled same as the dongle unplugged which tears down the mainlink
> > and disables the phy. This patch fixes this problem by only tearing
> > down the mainlink but keeping phy enabled at irq_hpd with
> > sink_count = 0 handle so that next irq_hpe with sink_count =1 can be
> > handled by setup mainlink only.
> >
> > Changes in v2:
> > -- add ctrl->phy_Power_count
> >
> > Signed-off-by: Kuogee Hsieh <khsieh@xxxxxxxxxxxxxx>
> > ---
> >  drivers/gpu/drm/msm/dp/dp_catalog.c |  5 +--
> >  drivers/gpu/drm/msm/dp/dp_ctrl.c    | 83 
> > ++++++++++++++++++++++++++++++++++---
> >  drivers/gpu/drm/msm/dp/dp_ctrl.h    |  2 +
> >  drivers/gpu/drm/msm/dp/dp_display.c | 46 +++++++++++++++-----
> >  4 files changed, 118 insertions(+), 18 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/msm/dp/dp_catalog.c 
> > b/drivers/gpu/drm/msm/dp/dp_catalog.c
> > index b1a9b1b..f4f53f2 100644
> > --- a/drivers/gpu/drm/msm/dp/dp_catalog.c
> > +++ b/drivers/gpu/drm/msm/dp/dp_catalog.c
> > @@ -582,10 +582,9 @@ void dp_catalog_ctrl_hpd_config(struct dp_catalog 
> > *dp_catalog)
> >
> >         u32 reftimer = dp_read_aux(catalog, REG_DP_DP_HPD_REFTIMER);
> >
> > -       /* enable HPD interrupts */
> > +       /* enable HPD plug and unplug interrupts */
> >         dp_catalog_hpd_config_intr(dp_catalog,
> > -               DP_DP_HPD_PLUG_INT_MASK | DP_DP_IRQ_HPD_INT_MASK
> > -               | DP_DP_HPD_UNPLUG_INT_MASK | 
> > DP_DP_HPD_REPLUG_INT_MASK, true);
> > +               DP_DP_HPD_PLUG_INT_MASK | DP_DP_HPD_UNPLUG_INT_MASK, 
> > true);
> >
> >         /* Configure REFTIMER and enable it */
> >         reftimer |= DP_DP_HPD_REFTIMER_ENABLE;
> > diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.c 
> > b/drivers/gpu/drm/msm/dp/dp_ctrl.c
> > index 8d59eb9..b5bed5f 100644
> > --- a/drivers/gpu/drm/msm/dp/dp_ctrl.c
> > +++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c
> > @@ -77,6 +77,8 @@ struct dp_ctrl_private {
> >         struct dp_parser *parser;
> >         struct dp_catalog *catalog;
> >
> > +       int phy_power_count;
>
> This is still redundant. Please restructure the code to call the power
> on/off function in one place and the init/exit function in another so
> that we don't have to reference count it.

ok, v3 patch uploaded