Re: [PATCH v6 06/11] drm/mediatek: Add pm runtime support for ovl and rdma

[Dafna Hirschfeld <dafna.hirschfeld@collabora.com>]

On 14.07.21 04:56, Yong Wu wrote:
> From: Yongqiang Niu <yongqiang.niu@mediatek.com>
> 
> Prepare for smi cleaning up "mediatek,larb".
> 
> Display use the dispsys device to call pm_rumtime_get_sync before.
> This patch add pm_runtime_xx with ovl and rdma device whose nodes has
> "iommus" property, then display could help pm_runtime_get for smi via
> ovl or rdma device.
> 
> CC: CK Hu <ck.hu@mediatek.com>
> Signed-off-by: Yongqiang Niu <yongqiang.niu@mediatek.com>
> Signed-off-by: Yong Wu <yong.wu@mediatek.com>
> (Yong: Use pm_runtime_resume_and_get instead of pm_runtime_get_sync)
> Acked-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>
> ---
>   drivers/gpu/drm/mediatek/mtk_disp_ovl.c  |  9 ++++++++-
>   drivers/gpu/drm/mediatek/mtk_disp_rdma.c |  9 ++++++++-
>   drivers/gpu/drm/mediatek/mtk_drm_crtc.c  | 12 +++++++++++-
>   3 files changed, 27 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/mediatek/mtk_disp_ovl.c b/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
> index fa9d79963cd3..ea5760f856ec 100644
> --- a/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
> +++ b/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
> @@ -11,6 +11,7 @@
>   #include <linux/of_device.h>
>   #include <linux/of_irq.h>
>   #include <linux/platform_device.h>
> +#include <linux/pm_runtime.h>
>   #include <linux/soc/mediatek/mtk-cmdq.h>
>   
>   #include "mtk_disp_drv.h"
> @@ -414,15 +415,21 @@ static int mtk_disp_ovl_probe(struct platform_device *pdev)
>   		return ret;
>   	}
>   
> +	pm_runtime_enable(dev);
> +
>   	ret = component_add(dev, &mtk_disp_ovl_component_ops);
> -	if (ret)
> +	if (ret) {
> +		pm_runtime_disable(dev);
>   		dev_err(dev, "Failed to add component: %d\n", ret);
> +	}
>   
>   	return ret;
>   }
>   
>   static int mtk_disp_ovl_remove(struct platform_device *pdev)
>   {
> +	pm_runtime_disable(&pdev->dev);
> +
>   	return 0;
>   }
>   
> diff --git a/drivers/gpu/drm/mediatek/mtk_disp_rdma.c b/drivers/gpu/drm/mediatek/mtk_disp_rdma.c
> index 705f28ceb4dd..0f31d1c8e37c 100644
> --- a/drivers/gpu/drm/mediatek/mtk_disp_rdma.c
> +++ b/drivers/gpu/drm/mediatek/mtk_disp_rdma.c
> @@ -9,6 +9,7 @@
>   #include <linux/of_device.h>
>   #include <linux/of_irq.h>
>   #include <linux/platform_device.h>
> +#include <linux/pm_runtime.h>
>   #include <linux/soc/mediatek/mtk-cmdq.h>
>   
>   #include "mtk_disp_drv.h"
> @@ -327,9 +328,13 @@ static int mtk_disp_rdma_probe(struct platform_device *pdev)
>   
>   	platform_set_drvdata(pdev, priv);
>   
> +	pm_runtime_enable(dev);
> +
>   	ret = component_add(dev, &mtk_disp_rdma_component_ops);
> -	if (ret)
> +	if (ret) {
> +		pm_runtime_disable(dev);
>   		dev_err(dev, "Failed to add component: %d\n", ret);
> +	}
>   
>   	return ret;
>   }
> @@ -338,6 +343,8 @@ static int mtk_disp_rdma_remove(struct platform_device *pdev)
>   {
>   	component_del(&pdev->dev, &mtk_disp_rdma_component_ops);
>   
> +	pm_runtime_disable(&pdev->dev);
> +
>   	return 0;
>   }
>   
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> index 474efb844249..08e3f352377d 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> @@ -557,9 +557,15 @@ static void mtk_drm_crtc_atomic_enable(struct drm_crtc *crtc,
>   		return;
>   	}
>   
> +	ret = pm_runtime_resume_and_get(comp->dev);
> +	if (ret < 0)
> +		DRM_DEV_ERROR(comp->dev, "Failed to enable power domain: %d\n",
> +			      ret);

shouldn't the code return in case of failure here?

Thanks,
Dafna

> +
>   	ret = mtk_crtc_ddp_hw_init(mtk_crtc);
>   	if (ret) {
>   		mtk_smi_larb_put(comp->larb_dev);
> +		pm_runtime_put(comp->dev);
>   		return;
>   	}
>   
> @@ -572,7 +578,7 @@ static void mtk_drm_crtc_atomic_disable(struct drm_crtc *crtc,
>   {
>   	struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);
>   	struct mtk_ddp_comp *comp = mtk_crtc->ddp_comp[0];
> -	int i;
> +	int i, ret;
>   
>   	DRM_DEBUG_DRIVER("%s %d\n", __func__, crtc->base.id);
>   	if (!mtk_crtc->enabled)
> @@ -596,6 +602,10 @@ static void mtk_drm_crtc_atomic_disable(struct drm_crtc *crtc,
>   	drm_crtc_vblank_off(crtc);
>   	mtk_crtc_ddp_hw_fini(mtk_crtc);
>   	mtk_smi_larb_put(comp->larb_dev);
> +	ret = pm_runtime_put(comp->dev);
> +	if (ret < 0)
> +		DRM_DEV_ERROR(comp->dev, "Failed to disable power domain: %d\n",
> +			      ret);
>   
>   	mtk_crtc->enabled = false;
>   }
>