On Fri, May 3, 2024 at 5:12 PM Lucas Stach <l.stach@xxxxxxxxxxxxxx> wrote:
>
> There is no reason to enable the controller clock in driver probe, as
> there is no HW initialization done in this function. Instead rely on
> either runtime PM to handle the controller clock or statically enable
> it in the driver bind routine, after which real hardware access is
> required to work.
>
> Signed-off-by: Lucas Stach <l.stach@xxxxxxxxxxxxxx>
> ---
> .../drm/bridge/analogix/analogix_dp_core.c | 78 +++++++++++--------
> 1 file changed, 45 insertions(+), 33 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
> index 0af2a70ae5bf..9e3308257586 100644
> --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
> +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
> @@ -1658,8 +1658,6 @@ analogix_dp_probe(struct device *dev, struct analogix_dp_plat_data *plat_data)
> return ERR_CAST(dp->clock);
> }
>
> - clk_prepare_enable(dp->clock);
> -
> res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>
> dp->reg_base = devm_ioremap_resource(&pdev->dev, res);
> @@ -1721,6 +1719,29 @@ analogix_dp_probe(struct device *dev, struct analogix_dp_plat_data *plat_data)
> }
> EXPORT_SYMBOL_GPL(analogix_dp_probe);
>
> +
> +int analogix_dp_suspend(struct analogix_dp_device *dp)
> +{
> + clk_disable_unprepare(dp->clock);
> +
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(analogix_dp_suspend);
> +
> +int analogix_dp_resume(struct analogix_dp_device *dp)
> +{
> + int ret;
> +
> + ret = clk_prepare_enable(dp->clock);
> + if (ret < 0) {
> + DRM_ERROR("Failed to prepare_enable the clock clk [%d]\n", ret);
> + return ret;
> + }
> +
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(analogix_dp_resume);
> +
> int analogix_dp_bind(struct analogix_dp_device *dp, struct drm_device *drm_dev)
> {
> int ret;
> @@ -1728,9 +1749,15 @@ int analogix_dp_bind(struct analogix_dp_device *dp, struct drm_device *drm_dev)
> dp->drm_dev = drm_dev;
> dp->encoder = dp->plat_data->encoder;
>
> - pm_runtime_use_autosuspend(dp->dev);
> - pm_runtime_set_autosuspend_delay(dp->dev, 100);
> - pm_runtime_enable(dp->dev);
> + if (IS_ENABLED(CONFIG_PM)) {
> + pm_runtime_use_autosuspend(dp->dev);
> + pm_runtime_set_autosuspend_delay(dp->dev, 100);
> + pm_runtime_enable(dp->dev);
> + } else {
> + ret = analogix_dp_resume(dp);
> + if (ret)
> + return ret;
> + }
>
> dp->aux.name = "DP-AUX";
> dp->aux.transfer = analogix_dpaux_transfer;
> @@ -1754,8 +1781,12 @@ int analogix_dp_bind(struct analogix_dp_device *dp, struct drm_device *drm_dev)
> err_unregister_aux:
> drm_dp_aux_unregister(&dp->aux);
> err_disable_pm_runtime:
> - pm_runtime_dont_use_autosuspend(dp->dev);
> - pm_runtime_disable(dp->dev);
> + if (IS_ENABLED(CONFIG_PM)) {
> + pm_runtime_dont_use_autosuspend(dp->dev);
> + pm_runtime_disable(dp->dev);
> + } else {
> + analogix_dp_suspend(dp);
> + }
>
> return ret;
> }
> @@ -1772,40 +1803,21 @@ void analogix_dp_unbind(struct analogix_dp_device *dp)
> }
>
> drm_dp_aux_unregister(&dp->aux);
> - pm_runtime_dont_use_autosuspend(dp->dev);
> - pm_runtime_disable(dp->dev);
> +
> + if (IS_ENABLED(CONFIG_PM)) {
> + pm_runtime_dont_use_autosuspend(dp->dev);
> + pm_runtime_disable(dp->dev);
> + } else {
> + analogix_dp_suspend(dp);
> + }
> }
> EXPORT_SYMBOL_GPL(analogix_dp_unbind);
>
> void analogix_dp_remove(struct analogix_dp_device *dp)
> {
> - clk_disable_unprepare(dp->clock);
> }
> EXPORT_SYMBOL_GPL(analogix_dp_remove);
>
> -#ifdef CONFIG_PM
> -int analogix_dp_suspend(struct analogix_dp_device *dp)
> -{
> - clk_disable_unprepare(dp->clock);
> - return 0;
> -}
> -EXPORT_SYMBOL_GPL(analogix_dp_suspend);
> -
> -int analogix_dp_resume(struct analogix_dp_device *dp)
> -{
> - int ret;
> -
> - ret = clk_prepare_enable(dp->clock);
> - if (ret < 0) {
> - DRM_ERROR("Failed to prepare_enable the clock clk [%d]\n", ret);
> - return ret;
> - }
> -
> - return 0;
> -}
> -EXPORT_SYMBOL_GPL(analogix_dp_resume);
> -#endif
> -
> int analogix_dp_start_crc(struct drm_connector *connector)
> {
> struct analogix_dp_device *dp = to_dp(connector);
> --
> 2.39.2
>
Reviewed-by: Robert Foss <rfoss@xxxxxxxxxx>
