Quoting Kuogee Hsieh (2021-05-05 14:52:01) > 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. > > Signed-off-by: Kuogee Hsieh <khsieh@xxxxxxxxxxxxxx> > --- It works for me, but I question the poking into phy internals below. > drivers/gpu/drm/msm/dp/dp_catalog.c | 5 +-- > drivers/gpu/drm/msm/dp/dp_ctrl.c | 78 +++++++++++++++++++++++++++++++++---- > drivers/gpu/drm/msm/dp/dp_ctrl.h | 2 + > drivers/gpu/drm/msm/dp/dp_display.c | 47 +++++++++++++++++----- > 4 files changed, 111 insertions(+), 21 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..5922259 100644 > --- a/drivers/gpu/drm/msm/dp/dp_ctrl.c > +++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c > @@ -1334,8 +1334,10 @@ static int dp_ctrl_enable_mainlink_clocks(struct dp_ctrl_private *ctrl) > dp_ctrl_set_clock_rate(ctrl, DP_CTRL_PM, "ctrl_link", > ctrl->link->link_params.rate * 1000); > > - phy_configure(phy, &dp_io->phy_opts); > - phy_power_on(phy); > + if (!phy->power_count) { > + phy_configure(phy, &dp_io->phy_opts); > + phy_power_on(phy); > + } > > ret = dp_power_clk_enable(ctrl->power, DP_CTRL_PM, true); > if (ret) > @@ -1414,6 +1416,10 @@ void dp_ctrl_host_deinit(struct dp_ctrl *dp_ctrl) > phy = dp_io->phy; > > dp_catalog_ctrl_enable_irq(ctrl->catalog, false); > + > + if (phy->power_count) > + phy_power_off(phy); > + > phy_exit(phy); > > DRM_DEBUG_DP("Host deinitialized successfully\n"); > @@ -1445,7 +1451,6 @@ static int dp_ctrl_reinitialize_mainlink(struct dp_ctrl_private *ctrl) > > dp_catalog_ctrl_mainlink_ctrl(ctrl->catalog, false); > opts_dp->lanes = ctrl->link->link_params.num_lanes; > - phy_configure(phy, &dp_io->phy_opts); > /* > * Disable and re-enable the mainlink clock since the > * link clock might have been adjusted as part of the > @@ -1456,9 +1461,13 @@ static int dp_ctrl_reinitialize_mainlink(struct dp_ctrl_private *ctrl) > DRM_ERROR("Failed to disable clocks. ret=%d\n", ret); > return ret; > } > - phy_power_off(phy); > - /* hw recommended delay before re-enabling clocks */ > - msleep(20); > + > + if (phy->power_count) { I don't believe members of 'phy' are supposed to be looked at by various phy consumer drivers. Vinod, is that right? > + phy_configure(phy, &dp_io->phy_opts); > + phy_power_off(phy); > + /* hw recommended delay before re-enabling clocks */ > + msleep(20); > + } > > ret = dp_ctrl_enable_mainlink_clocks(ctrl); > if (ret) { > @@ -1487,7 +1496,9 @@ static int dp_ctrl_deinitialize_mainlink(struct dp_ctrl_private *ctrl) > DRM_ERROR("Failed to disable link clocks. ret=%d\n", ret); > } > > - phy_power_off(phy); > + if (phy->power_count) > + phy_power_off(phy); > + Given that init/power_on are both refcounted, maybe the code could call phy_init()/phy_exit() when hpd changes, i.e. the link is up and phy_power_on()/phy_power_off() when the mainlink is supposed to be enabled (I guess when we're going to display bit to the screen?). That way we don't have to check the counts. > phy_exit(phy); > > return 0;