Re: [PATCH] drm/stm: add sleep power management

From: Philippe CORNU
Date: Tue Mar 26 2019 - 09:02:40 EST


(+ Benjamin)

Dear Yannick,
Many thanks for your patch.
Acked-by: Philippe Cornu <philippe.cornu@xxxxxx>

Dear Benjamin,
May I ask you please to merge this patch + "drm/stm: dw_mipi_dsi-stm:
add sleep power management" on drm-misc, if you agree of course and when
you think it is the right time (next week?)
Big thanks,

Philippe :-)


On 3/21/19 9:15 AM, Yannick Fertrà wrote:
> Implements system sleep power management ops.
>
> Signed-off-by: Yannick Fertrà <yannick.fertre@xxxxxx>
> ---
> drivers/gpu/drm/stm/drv.c | 35 +++++++++++++++++++++++++++++++++++
> drivers/gpu/drm/stm/ltdc.c | 24 ++++++++++++++++++++++++
> drivers/gpu/drm/stm/ltdc.h | 3 +++
> 3 files changed, 62 insertions(+)
>
> diff --git a/drivers/gpu/drm/stm/drv.c b/drivers/gpu/drm/stm/drv.c
> index 0a7f933..5834ef5 100644
> --- a/drivers/gpu/drm/stm/drv.c
> +++ b/drivers/gpu/drm/stm/drv.c
> @@ -129,6 +129,40 @@ static void drv_unload(struct drm_device *ddev)
> drm_mode_config_cleanup(ddev);
> }
>
> +static __maybe_unused int drv_suspend(struct device *dev)
> +{
> + struct drm_device *ddev = dev_get_drvdata(dev);
> + struct ltdc_device *ldev = ddev->dev_private;
> + struct drm_atomic_state *state;
> +
> + drm_kms_helper_poll_disable(ddev);
> + state = drm_atomic_helper_suspend(ddev);
> + if (IS_ERR(state)) {
> + drm_kms_helper_poll_enable(ddev);
> + return PTR_ERR(state);
> + }
> + ldev->suspend_state = state;
> + ltdc_suspend(ddev);
> +
> + return 0;
> +}
> +
> +static __maybe_unused int drv_resume(struct device *dev)
> +{
> + struct drm_device *ddev = dev_get_drvdata(dev);
> + struct ltdc_device *ldev = ddev->dev_private;
> +
> + ltdc_resume(ddev);
> + drm_atomic_helper_resume(ddev, ldev->suspend_state);
> + drm_kms_helper_poll_enable(ddev);
> +
> + return 0;
> +}
> +
> +static const struct dev_pm_ops drv_pm_ops = {
> + SET_SYSTEM_SLEEP_PM_OPS(drv_suspend, drv_resume)
> +};
> +
> static int stm_drm_platform_probe(struct platform_device *pdev)
> {
> struct device *dev = &pdev->dev;
> @@ -186,6 +220,7 @@ static struct platform_driver stm_drm_platform_driver = {
> .driver = {
> .name = "stm32-display",
> .of_match_table = drv_dt_ids,
> + .pm = &drv_pm_ops,
> },
> };
>
> diff --git a/drivers/gpu/drm/stm/ltdc.c b/drivers/gpu/drm/stm/ltdc.c
> index b1741a9..32fd6a3 100644
> --- a/drivers/gpu/drm/stm/ltdc.c
> +++ b/drivers/gpu/drm/stm/ltdc.c
> @@ -1062,6 +1062,30 @@ static int ltdc_get_caps(struct drm_device *ddev)
> return 0;
> }
>
> +void ltdc_suspend(struct drm_device *ddev)
> +{
> + struct ltdc_device *ldev = ddev->dev_private;
> +
> + DRM_DEBUG_DRIVER("\n");
> + clk_disable_unprepare(ldev->pixel_clk);
> +}
> +
> +int ltdc_resume(struct drm_device *ddev)
> +{
> + struct ltdc_device *ldev = ddev->dev_private;
> + int ret;
> +
> + DRM_DEBUG_DRIVER("\n");
> +
> + ret = clk_prepare_enable(ldev->pixel_clk);
> + if (ret) {
> + DRM_ERROR("failed to enable pixel clock (%d)\n", ret);
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> int ltdc_load(struct drm_device *ddev)
> {
> struct platform_device *pdev = to_platform_device(ddev->dev);
> diff --git a/drivers/gpu/drm/stm/ltdc.h b/drivers/gpu/drm/stm/ltdc.h
> index e46f477..a1ad0ae 100644
> --- a/drivers/gpu/drm/stm/ltdc.h
> +++ b/drivers/gpu/drm/stm/ltdc.h
> @@ -36,6 +36,7 @@ struct ltdc_device {
> u32 error_status;
> u32 irq_status;
> struct fps_info plane_fpsi[LTDC_MAX_LAYER];
> + struct drm_atomic_state *suspend_state;
> };
>
> bool ltdc_crtc_scanoutpos(struct drm_device *dev, unsigned int pipe,
> @@ -45,5 +46,7 @@ bool ltdc_crtc_scanoutpos(struct drm_device *dev, unsigned int pipe,
>
> int ltdc_load(struct drm_device *ddev);
> void ltdc_unload(struct drm_device *ddev);
> +void ltdc_suspend(struct drm_device *ddev);
> +int ltdc_resume(struct drm_device *ddev);
>
> #endif
>