[PATCH v1 2/5] drm/msm/dp: incorporate pm_runtime framework into DP driver
Dmitry Baryshkov
dmitry.baryshkov at linaro.org
Sat Jul 8 00:04:48 UTC 2023
On 08/07/2023 02:52, Kuogee Hsieh wrote:
> Incorporating pm runtime framework into DP driver so that power
> and clock resource handling can be centralized allowing easier
> control of these resources in preparation of registering aux bus
> uring probe.
>
> Signed-off-by: Kuogee Hsieh <quic_khsieh at quicinc.com>
> ---
> drivers/gpu/drm/msm/dp/dp_aux.c | 3 ++
> drivers/gpu/drm/msm/dp/dp_display.c | 75 +++++++++++++++++++++++++++++--------
> 2 files changed, 63 insertions(+), 15 deletions(-)
>
> diff --git a/drivers/gpu/drm/msm/dp/dp_aux.c b/drivers/gpu/drm/msm/dp/dp_aux.c
> index 8e3b677..c592064 100644
> --- a/drivers/gpu/drm/msm/dp/dp_aux.c
> +++ b/drivers/gpu/drm/msm/dp/dp_aux.c
> @@ -291,6 +291,7 @@ static ssize_t dp_aux_transfer(struct drm_dp_aux *dp_aux,
> return -EINVAL;
> }
>
> + pm_runtime_get_sync(dp_aux->dev);
Let me quote the function's documentation:
Consider using pm_runtime_resume_and_get() instead of it, especially if
its return value is checked by the caller, as this is likely to result
in cleaner code.
So two notes concerning the whole patch:
- error checking is missing
- please use pm_runtime_resume_and_get() instead.
> mutex_lock(&aux->mutex);
> if (!aux->initted) {
> ret = -EIO;
> @@ -364,6 +365,8 @@ static ssize_t dp_aux_transfer(struct drm_dp_aux *dp_aux,
>
> exit:
> mutex_unlock(&aux->mutex);
> + pm_runtime_mark_last_busy(dp_aux->dev);
> + pm_runtime_put_autosuspend(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 76f1395..2c5706a 100644
> --- a/drivers/gpu/drm/msm/dp/dp_display.c
> +++ b/drivers/gpu/drm/msm/dp/dp_display.c
> @@ -309,6 +309,10 @@ static int dp_display_bind(struct device *dev, struct device *master,
> goto end;
> }
>
> + pm_runtime_enable(dev);
devm_pm_runtime_enable() removes need for a cleanup.
> + pm_runtime_set_autosuspend_delay(dev, 1000);
> + pm_runtime_use_autosuspend(dev);
Why do you want to use autosuspend here?
> +
> return 0;
> end:
> return rc;
> @@ -320,9 +324,8 @@ 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);
> + pm_runtime_dont_use_autosuspend(dev);
> + pm_runtime_disable(dev);
>
> kthread_stop(dp->ev_tsk);
>
> @@ -466,10 +469,12 @@ static void dp_display_host_init(struct dp_display_private *dp)
> dp->dp_display.connector_type, dp->core_initialized,
> dp->phy_initialized);
>
> - dp_power_init(dp->power);
> - dp_ctrl_reset_irq_ctrl(dp->ctrl, true);
> - dp_aux_init(dp->aux);
> - dp->core_initialized = true;
> + if (!dp->core_initialized) {
> + dp_power_init(dp->power);
> + dp_ctrl_reset_irq_ctrl(dp->ctrl, true);
> + dp_aux_init(dp->aux);
> + dp->core_initialized = true;
> + }
Is this relevant to PM runtime? I don't think so.
> }
>
> static void dp_display_host_deinit(struct dp_display_private *dp)
> @@ -478,10 +483,12 @@ static void dp_display_host_deinit(struct dp_display_private *dp)
> dp->dp_display.connector_type, dp->core_initialized,
> dp->phy_initialized);
>
> - dp_ctrl_reset_irq_ctrl(dp->ctrl, false);
> - dp_aux_deinit(dp->aux);
> - dp_power_deinit(dp->power);
> - dp->core_initialized = false;
> + if (dp->core_initialized) {
> + dp_ctrl_reset_irq_ctrl(dp->ctrl, false);
> + dp_aux_deinit(dp->aux);
> + dp_power_deinit(dp->power);
> + dp->core_initialized = false;
> + }
> }
>
> static int dp_display_usbpd_configure_cb(struct device *dev)
> @@ -1304,6 +1311,39 @@ static int dp_display_remove(struct platform_device *pdev)
> dp_display_deinit_sub_modules(dp);
>
> platform_set_drvdata(pdev, NULL);
> + pm_runtime_put_sync_suspend(&pdev->dev);
> +
> + return 0;
> +}
> +
> +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;
> +
> + dp = container_of(dp_display, struct dp_display_private, dp_display);
> +
> + dp_display_host_phy_exit(dp);
> + dp_catalog_ctrl_hpd_enable(dp->catalog);
What? NO!
> + dp_display_host_deinit(dp);
> +
> + return 0;
> +}
> +
> +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);
> +
> + dp_display_host_init(dp);
> + if (dp_display->is_edp) {
> + dp_catalog_ctrl_hpd_enable(dp->catalog);
> + dp_display_host_phy_init(dp);
> + }
>
> return 0;
> }
> @@ -1409,6 +1449,7 @@ static int dp_pm_suspend(struct device *dev)
> }
>
> static const struct dev_pm_ops dp_pm_ops = {
> + SET_RUNTIME_PM_OPS(dp_pm_runtime_suspend, dp_pm_runtime_resume, NULL)
> .suspend = dp_pm_suspend,
> .resume = dp_pm_resume,
With the runtime PM in place, can we change suspend/resume to use
pm_runtime_force_suspend() and pm_runtime_force_resume() ?
> };
> @@ -1493,10 +1534,6 @@ 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);
Are you going to populate the AUX bus (which can cause AUX bus access)
without waking up the device?
> -
> /*
> * The code below assumes that the panel will finish probing
> * by the time devm_of_dp_aux_populate_ep_devices() returns.
> @@ -1604,6 +1641,7 @@ void dp_bridge_atomic_enable(struct drm_bridge *drm_bridge,
> dp_hpd_plug_handle(dp_display, 0);
Nearly the same question. Resume device before accessing registers.
>
> mutex_lock(&dp_display->event_mutex);
> + pm_runtime_get_sync(&dp_display->pdev->dev);
>
> state = dp_display->hpd_state;
> if (state != ST_DISPLAY_OFF && state != ST_MAINLINK_READY) {
> @@ -1684,6 +1722,8 @@ 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_display->pdev->dev);
> mutex_unlock(&dp_display->event_mutex);
> }
>
> @@ -1723,6 +1763,8 @@ void dp_bridge_hpd_enable(struct drm_bridge *bridge)
> struct dp_display_private *dp = container_of(dp_display, struct dp_display_private, dp_display);
>
> mutex_lock(&dp->event_mutex);
> + pm_runtime_get_sync(&dp->pdev->dev);
> +
> dp_catalog_ctrl_hpd_enable(dp->catalog);
>
> /* enable HDP interrupts */
> @@ -1744,6 +1786,9 @@ void dp_bridge_hpd_disable(struct drm_bridge *bridge)
> dp_catalog_ctrl_hpd_disable(dp->catalog);
>
> dp_display->internal_hpd = false;
> +
> + pm_runtime_mark_last_busy(&dp->pdev->dev);
> + pm_runtime_put_autosuspend(&dp->pdev->dev);
> mutex_unlock(&dp->event_mutex);
> }
>
--
With best wishes
Dmitry
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