Hello Sebastian, Sebastian Reichel <[email protected]> 于2026年6月13日周六 02:01写道：
> Add runtime PM stubs to the Synopsys DesignWare DisplayPort bridge > driver. Support is not enabled automatically and must be hooked up > in the vendor specific glue code. > > Signed-off-by: Sebastian Reichel <[email protected]> > --- > drivers/gpu/drm/bridge/synopsys/dw-dp.c | 27 +++++++++++++++++++++++++++ > include/drm/bridge/dw_dp.h | 3 +++ > 2 files changed, 30 insertions(+) > > diff --git a/drivers/gpu/drm/bridge/synopsys/dw-dp.c > b/drivers/gpu/drm/bridge/synopsys/dw-dp.c > index 7fa38145e35c..7f4f36c61484 100644 > --- a/drivers/gpu/drm/bridge/synopsys/dw-dp.c > +++ b/drivers/gpu/drm/bridge/synopsys/dw-dp.c > @@ -1465,6 +1465,8 @@ static ssize_t dw_dp_aux_transfer(struct drm_dp_aux > *aux, > if (WARN_ON(msg->size > 16)) > return -E2BIG; > > + ACQUIRE(pm_runtime_active_auto, pm)(dp->dev); > + > switch (msg->request & ~DP_AUX_I2C_MOT) { > case DP_AUX_NATIVE_WRITE: > case DP_AUX_I2C_WRITE: > @@ -1655,6 +1657,8 @@ static void dw_dp_bridge_atomic_enable(struct > drm_bridge *bridge, > struct drm_connector_state *conn_state; > int ret; > > + pm_runtime_get_sync(dp->dev); > + > connector = drm_atomic_get_new_connector_for_encoder(state, > bridge->encoder); > if (!connector) { > dev_err(dp->dev, "failed to get connector\n"); > @@ -1709,6 +1713,7 @@ static void dw_dp_bridge_atomic_disable(struct > drm_bridge *bridge, > dw_dp_link_disable(dp); > bitmap_zero(dp->sdp_reg_bank, SDP_REG_BANK_SIZE); > dw_dp_reset(dp); > + pm_runtime_put_autosuspend(dp->dev); > } > > static bool dw_dp_hpd_detect_link(struct dw_dp *dp, struct drm_connector > *connector) > @@ -1729,6 +1734,8 @@ static enum drm_connector_status > dw_dp_bridge_detect(struct drm_bridge *bridge, > { > struct dw_dp *dp = bridge_to_dp(bridge); > > + ACQUIRE(pm_runtime_active_auto, pm)(dp->dev); > This may not work correctly. Per the DW-DP TRM, the " HPD_HOT_PLUG bit is asserted only after the sink is attached and holds HPD high for at least 100ms". Consequently, reading this bit within 100ms after resuming runtime_pm may fail to detect the status. I've verified this behavior on a Rock 5B board—the HPD bit remains unreadable at this point.: +++ b/drivers/gpu/drm/bridge/synopsys/dw-dp.c @@ -1761,12 +1761,17 @@ static enum drm_connector_status dw_dp_bridge_detect(struct drm_bridge *bridge, ACQUIRE(pm_runtime_active_auto, pm)(dp->dev); - if (!dw_dp_hpd_detect(dp)) + if (!dw_dp_hpd_detect(dp)) { + printk(KERN_DEBUG "%s no hpd\n", __func__); return connector_status_disconnected; + } - if (!dw_dp_hpd_detect_link(dp, connector)) + if (!dw_dp_hpd_detect_link(dp, connector)) { + printk(KERN_DEBUG "%s no link\n", __func__); return connector_status_disconnected; + } + printk(KERN_DEBUG "%s connected\n", __func__); return connector_status_connected; } @@ -2149,6 +2154,7 @@ static irqreturn_t dw_dp_irq(int irq, void *data) u32 value; regmap_read(dp->regmap, DW_DP_GENERAL_INTERRUPT, &value); + printk(KERN_DEBUG "%s value: %d\n", __func__, value); if (!value) return IRQ_NONE; bootup [ 5.218035] panthor fb000000.gpu: [drm] Using Transparent Hugepage [ 5.219073] [drm] Initialized panthor 1.9.0 for fb000000.gpu on minor 1 [ 7.953973] r8169 0004:41:00.0 enP4p65s0: Link is Up - 1Gbps/Full - flow control off [ 8.601273] dw_dp_rockchip_runtime_resume ret: 0 [ 8.702748] dw_dp_irq value: 1 // (HPD irq 100 100ms after runtime_resume) [ 8.714236] dw_dp_irq value: 2 [ 8.714775] dw_dp_irq value: 2 [ 8.715201] dw_dp_irq value: 2 [ 8.715710] dw_dp_irq value: 2 [ 8.715744] dw_dp_bridge_detect connected [ 9.226752] dw_dp_rockchip_runtime_suspend Then run modetest: # modetest trying to open device '/dev/dri/card1'... is not a KMS device trying to open device '/dev/dri/card0'... done opened device `RockChip Soc DRM` on driver `rockchip` (version 1.0.0 at 0) Encoders: id crtc type possible crtcs possible clones 86 0 TMDS 0x00000004 0x00000001 88 0 TMDS 0x00000001 0x00000002 92 0 TMDS 0x00000002 0x00000004 Connectors: id encoder status name size (mm) modes encoders 87 0 disconnected DP-1 0x0 0 86 props: 1 EDID: [ 13.809398] rockchip-pm-domain fd8d8000.power-management:power-controller: sync_state() pending due to fdee0000.hdmi_receiver [ 29.225506] dw_dp_rockchip_runtime_resume ret: 0 [ 29.225940] dw_dp_bridge_detect no hpd // no HPD read here [ 29.326986] dw_dp_irq value: 1 // HPD irq ater 100ms [ 29.346609] dw_dp_irq value: 2 [ 29.347150] dw_dp_irq value: 2 [ 29.347578] dw_dp_irq value: 2 [ 29.348092] dw_dp_irq value: 2 if I add a mdelay(110) after ACQUIRE pm_runtime, the hdp can be read. index 02ca7fe725876..5959e79eb3e2b 100644 --- a/drivers/gpu/drm/bridge/synopsys/dw-dp.c +++ b/drivers/gpu/drm/bridge/synopsys/dw-dp.c @@ -1760,7 +1760,7 @@ static enum drm_connector_status dw_dp_bridge_detect(struct drm_bridge *bridge, struct dw_dp *dp = bridge_to_dp(bridge); ACQUIRE(pm_runtime_active_auto, pm)(dp->dev); - + mdelay(110); [ 13.816944] rockchip-pm-domain fd8d8000.power-management:power-controller: sync_state() pending due to fdee0000.hdmi_receiver [ 42.735529] dw_dp_rockchip_runtime_resume ret: 0 [ 42.837035] dw_dp_irq value: 1 [ 42.857458] dw_dp_irq value: 2 [ 42.857979] dw_dp_irq value: 2 [ 42.858387] dw_dp_irq value: 2 [ 42.858880] dw_dp_irq value: 2 [ 42.858897] dw_dp_bridge_detect connected + > if (!dw_dp_hpd_detect(dp)) > return connector_status_disconnected; > > @@ -2153,6 +2160,26 @@ void dw_dp_unbind(struct dw_dp *dp) > } > EXPORT_SYMBOL_GPL(dw_dp_unbind); > > +int dw_dp_runtime_suspend(struct dw_dp *dp) > +{ > + clk_disable_unprepare(dp->aux_clk); > + clk_disable_unprepare(dp->apb_clk); > + > + return 0; > +} > +EXPORT_SYMBOL_GPL(dw_dp_runtime_suspend); > + > +int dw_dp_runtime_resume(struct dw_dp *dp) > +{ > + clk_prepare_enable(dp->apb_clk); > + clk_prepare_enable(dp->aux_clk); > + > + dw_dp_init_hw(dp); > + > + return 0; > +} > +EXPORT_SYMBOL_GPL(dw_dp_runtime_resume); > + > MODULE_AUTHOR("Andy Yan <[email protected]>"); > MODULE_DESCRIPTION("DW DP Core Library"); > MODULE_LICENSE("GPL"); > diff --git a/include/drm/bridge/dw_dp.h b/include/drm/bridge/dw_dp.h > index 2127afa26b2c..3037e0290861 100644 > --- a/include/drm/bridge/dw_dp.h > +++ b/include/drm/bridge/dw_dp.h > @@ -28,4 +28,7 @@ struct dw_dp_plat_data { > struct dw_dp *dw_dp_bind(struct device *dev, struct drm_encoder *encoder, > const struct dw_dp_plat_data *plat_data); > void dw_dp_unbind(struct dw_dp *dp); > + > +int dw_dp_runtime_suspend(struct dw_dp *dp); > +int dw_dp_runtime_resume(struct dw_dp *dp); > #endif /* __DW_DP__ */ > > -- > 2.53.0 > > >
