Re: [PATCH v8 5/7] drm/msm/dp: incorporate pm_runtime framework into DP driver

From: Dmitry Baryshkov
Date: Wed Nov 29 2023 - 23:01:31 EST


On Wed, 29 Nov 2023 at 19:47, Kuogee Hsieh <quic_khsieh@xxxxxxxxxxx> wrote:
>
> Currently DP driver is executed independent of PM runtime framework.
> This leads msm eDP panel can not being detected by edp_panel driver
> during generic_edp_panel_probe() due to AUX DPCD read failed at
> edp panel driver. Incorporate PM runtime framework into DP driver so
> that host controller's power and clocks are enable/disable through
> PM runtime mechanism. Once PM runtime framework is incorporated into
> DP driver, waking up device from power up path is not necessary. Hence
> remove it.
>
> After incorporating pm_runtime framework into eDP/DP driver,
> dp_pm_suspend() to handle power off both DP phy and controller during
> suspend and dp_pm_resume() to handle power on both DP phy and controller
> during resume are not necessary. Therefore both dp_pm_suspend() and
> dp_pm_resume() are dropped and replace with dp_pm_runtime_suspend() and
> dp_pm_runtime_resume() respectively.

There were comments for v7 of this patch that were not handled in this
revision. Please take care of them.

>
> Changes in v7:
> -- add comments to dp_pm_runtime_resume()
> -- add comments to dp_bridge_hpd_enable()
> -- delete dp->hpd_state = ST_DISCONNECTED from dp_bridge_hpd_notify()
>
> Changes in v6:
> -- delete dp_power_client_deinit(dp->power);
> -- remove if (!dp->dp_display.is_edp) condition checkout at plug_handle()
> -- remove if (!dp->dp_display.is_edp) condition checkout at unplug_handle()
> -- add IRQF_NO_AUTOEN to devm_request_irq()
> -- add enable_irq() and disable_irq() to pm_runtime_resume()/suspend()
> -- del dp->hpd_state = ST_DISCONNECTED from dp_bridge_hpd_disable()
>
> Changes in v5:
> -- remove pm_runtime_put_autosuspend feature, use pm_runtime_put_sync()
> -- squash add pm_runtime_force_suspend()/resume() patch into this patch
>
> Changes in v4:
> -- reworded commit text to explain why pm_framework is required for
> edp panel
> -- reworded commit text to explain autosuspend is choiced
> -- delete EV_POWER_PM_GET and PM_EV_POWER_PUT from changes #3
> -- delete dp_display_pm_get() and dp_display_pm_Put() from changes #3
> -- return value from pm_runtime_resume_and_get() directly
> -- check return value of devm_pm_runtime_enable()
> -- delete pm_runtime_xxx from dp_display_remove()
> -- drop dp_display_host_init() from EV_HPD_INIT_SETUP
> -- drop both dp_pm_prepare() and dp_pm_compete() from this change
> -- delete ST_SUSPENDED state
> -- rewording commit text to add more details regrading the purpose
> of this change
>
> Changes in v3:
> -- incorporate removing pm_runtime_xx() from dp_pwer.c to this patch
> -- use pm_runtime_resume_and_get() instead of pm_runtime_get()
> -- error checking pm_runtime_resume_and_get() return value
> -- add EV_POWER_PM_GET and PM_EV_POWER_PUT to handle HPD_GPIO case
> -- replace dp_pm_suspend() with pm_runtime_force_suspend()
> -- replace dp_pm_resume() with pm_runtime_force_resume()
>
> Signed-off-by: Kuogee Hsieh <quic_khsieh@xxxxxxxxxxx>
> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
> ---
> drivers/gpu/drm/msm/dp/dp_aux.c | 5 +
> drivers/gpu/drm/msm/dp/dp_display.c | 181 ++++++++++++++----------------------
> drivers/gpu/drm/msm/dp/dp_power.c | 16 ----
> drivers/gpu/drm/msm/dp/dp_power.h | 11 ---
> 4 files changed, 75 insertions(+), 138 deletions(-)
>
> diff --git a/drivers/gpu/drm/msm/dp/dp_aux.c b/drivers/gpu/drm/msm/dp/dp_aux.c
> index 8e3b677..10b6eeb 100644
> --- a/drivers/gpu/drm/msm/dp/dp_aux.c
> +++ b/drivers/gpu/drm/msm/dp/dp_aux.c
> @@ -291,6 +291,10 @@ static ssize_t dp_aux_transfer(struct drm_dp_aux *dp_aux,
> return -EINVAL;
> }
>
> + ret = pm_runtime_resume_and_get(dp_aux->dev);
> + if (ret)
> + return ret;
> +
> mutex_lock(&aux->mutex);
> if (!aux->initted) {
> ret = -EIO;
> @@ -364,6 +368,7 @@ static ssize_t dp_aux_transfer(struct drm_dp_aux *dp_aux,
>
> exit:
> mutex_unlock(&aux->mutex);
> + pm_runtime_put_sync(dp_aux->dev);
>
> return ret;
> }
> diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
> index a99a786..9520d83 100644
> --- a/drivers/gpu/drm/msm/dp/dp_display.c
> +++ b/drivers/gpu/drm/msm/dp/dp_display.c
> @@ -49,7 +49,6 @@ enum {
> ST_CONNECTED,
> ST_DISCONNECT_PENDING,
> ST_DISPLAY_OFF,
> - ST_SUSPENDED,
> };
>
> enum {
> @@ -309,10 +308,6 @@ static void dp_display_unbind(struct device *dev, struct device *master,
> struct dp_display_private *dp = dev_get_dp_display_private(dev);
> struct msm_drm_private *priv = dev_get_drvdata(master);
>
> - /* disable all HPD interrupts */
> - if (dp->core_initialized)
> - dp_catalog_hpd_config_intr(dp->catalog, DP_DP_HPD_INT_MASK, false);
> -
> kthread_stop(dp->ev_tsk);
>
> of_dp_aux_depopulate_bus(dp->aux);
> @@ -542,6 +537,7 @@ static int dp_hpd_plug_handle(struct dp_display_private *dp, u32 data)
> {
> u32 state;
> int ret;
> + struct platform_device *pdev = dp->dp_display.pdev;
>
> mutex_lock(&dp->event_mutex);
>
> @@ -549,7 +545,7 @@ static int dp_hpd_plug_handle(struct dp_display_private *dp, u32 data)
> drm_dbg_dp(dp->drm_dev, "Before, type=%d hpd_state=%d\n",
> dp->dp_display.connector_type, state);
>
> - if (state == ST_DISPLAY_OFF || state == ST_SUSPENDED) {
> + if (state == ST_DISPLAY_OFF) {
> mutex_unlock(&dp->event_mutex);
> return 0;
> }
> @@ -566,7 +562,13 @@ static int dp_hpd_plug_handle(struct dp_display_private *dp, u32 data)
> return 0;
> }
>
> - ret = dp_display_usbpd_configure_cb(&dp->dp_display.pdev->dev);
> + ret = pm_runtime_resume_and_get(&pdev->dev);
> + if (ret) {
> + DRM_ERROR("failed to pm_runtime_resume\n");
> + return ret;
> + }
> +
> + ret = dp_display_usbpd_configure_cb(&pdev->dev);
> if (ret) { /* link train failed */
> dp->hpd_state = ST_DISCONNECTED;
> } else {
> @@ -598,6 +600,7 @@ static void dp_display_handle_plugged_change(struct msm_dp *dp_display,
> static int dp_hpd_unplug_handle(struct dp_display_private *dp, u32 data)
> {
> u32 state;
> + struct platform_device *pdev = dp->dp_display.pdev;
>
> mutex_lock(&dp->event_mutex);
>
> @@ -648,6 +651,7 @@ static int dp_hpd_unplug_handle(struct dp_display_private *dp, u32 data)
> dp->dp_display.connector_type, state);
>
> /* uevent will complete disconnection part */
> + pm_runtime_put_sync(&pdev->dev);
> mutex_unlock(&dp->event_mutex);
> return 0;
> }
> @@ -663,7 +667,7 @@ static int dp_irq_hpd_handle(struct dp_display_private *dp, u32 data)
> drm_dbg_dp(dp->drm_dev, "Before, type=%d hpd_state=%d\n",
> dp->dp_display.connector_type, state);
>
> - if (state == ST_DISPLAY_OFF || state == ST_SUSPENDED) {
> + if (state == ST_DISPLAY_OFF) {
> mutex_unlock(&dp->event_mutex);
> return 0;
> }
> @@ -1076,7 +1080,6 @@ static int hpd_event_thread(void *data)
>
> switch (todo->event_id) {
> case EV_HPD_INIT_SETUP:
> - dp_display_host_init(dp_priv);
> break;
> case EV_HPD_PLUG_INT:
> dp_hpd_plug_handle(dp_priv, todo->data);
> @@ -1168,7 +1171,9 @@ static int dp_display_request_irq(struct dp_display_private *dp)
> }
>
> rc = devm_request_irq(&pdev->dev, dp->irq, dp_display_irq_handler,
> - IRQF_TRIGGER_HIGH, "dp_display_isr", dp);
> + IRQF_TRIGGER_HIGH|IRQF_NO_AUTOEN,
> + "dp_display_isr", dp);
> +
> if (rc < 0) {
> DRM_ERROR("failed to request IRQ%u: %d\n",
> dp->irq, rc);
> @@ -1254,6 +1259,10 @@ static int dp_display_probe(struct platform_device *pdev)
>
> platform_set_drvdata(pdev, &dp->dp_display);
>
> + rc = devm_pm_runtime_enable(&pdev->dev);
> + if (rc)
> + goto err;
> +
> rc = dp_display_request_irq(dp);
> if (rc)
> goto err;
> @@ -1276,115 +1285,52 @@ static void dp_display_remove(struct platform_device *pdev)
> struct dp_display_private *dp = dev_get_dp_display_private(&pdev->dev);
>
> component_del(&pdev->dev, &dp_display_comp_ops);
> - dp_power_client_deinit(dp->power);
> dp_display_deinit_sub_modules(dp);
>
> platform_set_drvdata(pdev, NULL);
> }
>
> -static int dp_pm_resume(struct device *dev)
> +static int dp_pm_runtime_suspend(struct device *dev)
> {
> - struct platform_device *pdev = to_platform_device(dev);
> - struct msm_dp *dp_display = platform_get_drvdata(pdev);
> - struct dp_display_private *dp;
> - int sink_count = 0;
> -
> - dp = container_of(dp_display, struct dp_display_private, dp_display);
> -
> - mutex_lock(&dp->event_mutex);
> -
> - drm_dbg_dp(dp->drm_dev,
> - "Before, type=%d core_inited=%d phy_inited=%d power_on=%d\n",
> - dp->dp_display.connector_type, dp->core_initialized,
> - dp->phy_initialized, dp_display->power_on);
> -
> - /* start from disconnected state */
> - dp->hpd_state = ST_DISCONNECTED;
> -
> - /* turn on dp ctrl/phy */
> - dp_display_host_init(dp);
> -
> - if (dp_display->is_edp)
> - dp_catalog_ctrl_hpd_enable(dp->catalog);
> + struct dp_display_private *dp = dev_get_dp_display_private(dev);
>
> - if (dp_catalog_link_is_connected(dp->catalog)) {
> - /*
> - * set sink to normal operation mode -- D0
> - * before dpcd read
> - */
> - dp_display_host_phy_init(dp);
> - dp_link_psm_config(dp->link, &dp->panel->link_info, false);
> - sink_count = drm_dp_read_sink_count(dp->aux);
> - if (sink_count < 0)
> - sink_count = 0;
> + disable_irq(dp->irq);
>
> + if (dp->dp_display.is_edp) {
> dp_display_host_phy_exit(dp);
> + dp_catalog_ctrl_hpd_disable(dp->catalog);
> }
> -
> - dp->link->sink_count = sink_count;
> - /*
> - * can not declared display is connected unless
> - * HDMI cable is plugged in and sink_count of
> - * dongle become 1
> - * also only signal audio when disconnected
> - */
> - if (dp->link->sink_count) {
> - dp->dp_display.link_ready = true;
> - } else {
> - dp->dp_display.link_ready = false;
> - dp_display_handle_plugged_change(dp_display, false);
> - }
> -
> - drm_dbg_dp(dp->drm_dev,
> - "After, type=%d sink=%d conn=%d core_init=%d phy_init=%d power=%d\n",
> - dp->dp_display.connector_type, dp->link->sink_count,
> - dp->dp_display.link_ready, dp->core_initialized,
> - dp->phy_initialized, dp_display->power_on);
> -
> - mutex_unlock(&dp->event_mutex);
> + dp_display_host_deinit(dp);
>
> return 0;
> }
>
> -static int dp_pm_suspend(struct device *dev)
> +static int dp_pm_runtime_resume(struct device *dev)
> {
> - struct platform_device *pdev = to_platform_device(dev);
> - struct msm_dp *dp_display = platform_get_drvdata(pdev);
> - struct dp_display_private *dp;
> -
> - dp = container_of(dp_display, struct dp_display_private, dp_display);
> -
> - mutex_lock(&dp->event_mutex);
> -
> - drm_dbg_dp(dp->drm_dev,
> - "Before, type=%d core_inited=%d phy_inited=%d power_on=%d\n",
> - dp->dp_display.connector_type, dp->core_initialized,
> - dp->phy_initialized, dp_display->power_on);
> -
> - /* mainlink enabled */
> - if (dp_power_clk_status(dp->power, DP_CTRL_PM))
> - dp_ctrl_off_link_stream(dp->ctrl);
> -
> - dp_display_host_phy_exit(dp);
> -
> - /* host_init will be called at pm_resume */
> - dp_display_host_deinit(dp);
> -
> - dp->hpd_state = ST_SUSPENDED;
> -
> - drm_dbg_dp(dp->drm_dev,
> - "After, type=%d core_inited=%d phy_inited=%d power_on=%d\n",
> - dp->dp_display.connector_type, dp->core_initialized,
> - dp->phy_initialized, dp_display->power_on);
> + struct dp_display_private *dp = dev_get_dp_display_private(dev);
>
> - mutex_unlock(&dp->event_mutex);
> + /*
> + * for eDP, host cotroller, HPD block and PHY are enabled here
> + * but with HPD irq disabled
> + *
> + * for DP, only host controller is enabled here.
> + * HPD block is enabled at dp_bridge_hpd_enable()
> + * PHY will be enabled at plugin handler later
> + */
> + dp_display_host_init(dp);
> + if (dp->dp_display.is_edp) {
> + dp_catalog_ctrl_hpd_enable(dp->catalog);
> + dp_display_host_phy_init(dp);
> + }
>
> + enable_irq(dp->irq);
> return 0;
> }
>
> static const struct dev_pm_ops dp_pm_ops = {
> - .suspend = dp_pm_suspend,
> - .resume = dp_pm_resume,
> + SET_RUNTIME_PM_OPS(dp_pm_runtime_suspend, dp_pm_runtime_resume, NULL)
> + SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
> + pm_runtime_force_resume)
> };
>
> static struct platform_driver dp_display_driver = {
> @@ -1467,10 +1413,6 @@ static int dp_display_get_next_bridge(struct msm_dp *dp)
> aux_bus = of_get_child_by_name(dev->of_node, "aux-bus");
>
> if (aux_bus && dp->is_edp) {
> - dp_display_host_init(dp_priv);
> - dp_catalog_ctrl_hpd_enable(dp_priv->catalog);
> - dp_display_host_phy_init(dp_priv);
> -
> /*
> * The code below assumes that the panel will finish probing
> * by the time devm_of_dp_aux_populate_ep_devices() returns.
> @@ -1567,6 +1509,11 @@ void dp_bridge_atomic_enable(struct drm_bridge *drm_bridge,
> dp_hpd_plug_handle(dp_display, 0);
>
> mutex_lock(&dp_display->event_mutex);
> + if (pm_runtime_resume_and_get(&dp->pdev->dev)) {
> + DRM_ERROR("failed to pm_runtime_resume\n");
> + mutex_unlock(&dp_display->event_mutex);
> + return;
> + }
>
> state = dp_display->hpd_state;
> if (state != ST_DISPLAY_OFF && state != ST_MAINLINK_READY) {
> @@ -1631,10 +1578,9 @@ void dp_bridge_atomic_post_disable(struct drm_bridge *drm_bridge,
> mutex_lock(&dp_display->event_mutex);
>
> state = dp_display->hpd_state;
> - if (state != ST_DISCONNECT_PENDING && state != ST_CONNECTED) {
> - mutex_unlock(&dp_display->event_mutex);
> - return;
> - }
> + if (state != ST_DISCONNECT_PENDING && state != ST_CONNECTED)
> + drm_dbg_dp(dp->drm_dev, "type=%d wrong hpd_state=%d\n",
> + dp->connector_type, state);
>
> dp_display_disable(dp_display);
>
> @@ -1647,6 +1593,8 @@ void dp_bridge_atomic_post_disable(struct drm_bridge *drm_bridge,
> }
>
> drm_dbg_dp(dp->drm_dev, "type=%d Done\n", dp->connector_type);
> +
> + pm_runtime_put_sync(&dp->pdev->dev);
> mutex_unlock(&dp_display->event_mutex);
> }
>
> @@ -1685,7 +1633,21 @@ void dp_bridge_hpd_enable(struct drm_bridge *bridge)
> struct msm_dp *dp_display = dp_bridge->dp_display;
> struct dp_display_private *dp = container_of(dp_display, struct dp_display_private, dp_display);
>
> + /*
> + * this is for external DP with hpd irq enabled case,
> + * step-1: dp_pm_runtime_resume() enable dp host only
> + * step-2: enable hdp block and have hpd irq enabled here
> + * step-3: waiting for plugin irq while phy is not initialized
> + * step-4: DP PHY is initialized at plugin handler before link training
> + *
> + */
> mutex_lock(&dp->event_mutex);
> + if (pm_runtime_resume_and_get(&dp_display->pdev->dev)) {
> + DRM_ERROR("failed to resume power\n");
> + mutex_unlock(&dp->event_mutex);
> + return;
> + }
> +
> dp_catalog_ctrl_hpd_enable(dp->catalog);
>
> /* enable HDP interrupts */
> @@ -1707,6 +1669,8 @@ void dp_bridge_hpd_disable(struct drm_bridge *bridge)
> dp_catalog_ctrl_hpd_disable(dp->catalog);
>
> dp_display->internal_hpd = false;
> +
> + pm_runtime_put_sync(&dp_display->pdev->dev);
> mutex_unlock(&dp->event_mutex);
> }
>
> @@ -1721,11 +1685,6 @@ void dp_bridge_hpd_notify(struct drm_bridge *bridge,
> if (dp_display->internal_hpd)
> return;
>
> - if (!dp->core_initialized) {
> - drm_dbg_dp(dp->drm_dev, "not initialized\n");
> - return;
> - }
> -
> if (!dp_display->link_ready && status == connector_status_connected)
> dp_add_event(dp, EV_HPD_PLUG_INT, 0, 0);
> else if (dp_display->link_ready && status == connector_status_disconnected)
> diff --git a/drivers/gpu/drm/msm/dp/dp_power.c b/drivers/gpu/drm/msm/dp/dp_power.c
> index 5cb84ca..863c766 100644
> --- a/drivers/gpu/drm/msm/dp/dp_power.c
> +++ b/drivers/gpu/drm/msm/dp/dp_power.c
> @@ -152,20 +152,9 @@ int dp_power_client_init(struct dp_power *dp_power)
>
> power = container_of(dp_power, struct dp_power_private, dp_power);
>
> - pm_runtime_enable(power->dev);
> -
> return dp_power_clk_init(power);
> }
>
> -void dp_power_client_deinit(struct dp_power *dp_power)
> -{
> - struct dp_power_private *power;
> -
> - power = container_of(dp_power, struct dp_power_private, dp_power);
> -
> - pm_runtime_disable(power->dev);
> -}
> -
> int dp_power_init(struct dp_power *dp_power)
> {
> int rc = 0;
> @@ -173,11 +162,7 @@ int dp_power_init(struct dp_power *dp_power)
>
> power = container_of(dp_power, struct dp_power_private, dp_power);
>
> - pm_runtime_get_sync(power->dev);
> -
> rc = dp_power_clk_enable(dp_power, DP_CORE_PM, true);
> - if (rc)
> - pm_runtime_put_sync(power->dev);
>
> return rc;
> }
> @@ -189,7 +174,6 @@ int dp_power_deinit(struct dp_power *dp_power)
> power = container_of(dp_power, struct dp_power_private, dp_power);
>
> dp_power_clk_enable(dp_power, DP_CORE_PM, false);
> - pm_runtime_put_sync(power->dev);
> return 0;
> }
>
> diff --git a/drivers/gpu/drm/msm/dp/dp_power.h b/drivers/gpu/drm/msm/dp/dp_power.h
> index a3dec20..55ada51 100644
> --- a/drivers/gpu/drm/msm/dp/dp_power.h
> +++ b/drivers/gpu/drm/msm/dp/dp_power.h
> @@ -81,17 +81,6 @@ int dp_power_clk_enable(struct dp_power *power, enum dp_pm_type pm_type,
> int dp_power_client_init(struct dp_power *power);
>
> /**
> - * dp_power_clinet_deinit() - de-initialize clock and regulator modules
> - *
> - * @power: instance of power module
> - * return: 0 for success, error for failure.
> - *
> - * This API will de-initialize the DisplayPort's clocks and regulator
> - * modules.
> - */
> -void dp_power_client_deinit(struct dp_power *power);
> -
> -/**
> * dp_power_get() - configure and get the DisplayPort power module data
> *
> * @parser: instance of parser module
> --
> 2.7.4
>


--
With best wishes
Dmitry