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Message-ID: <903c71fb-61af-e12a-ca56-a49d4e930f9f@loongson.cn>
Date:   Tue, 27 Jun 2023 22:57:27 +0800
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Subject: Re: [32/39] drm: renesas: shmobile: Shutdown the display on remove
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To:     Geert Uytterhoeven <geert+renesas@glider.be>,
        Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
        Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>,
        David Airlie <airlied@gmail.com>,
        Daniel Vetter <daniel@ffwll.ch>,
        Thomas Zimmermann <tzimmermann@suse.de>,
        Magnus Damm <magnus.damm@gmail.com>
Cc:     linux-renesas-soc@vger.kernel.org, linux-kernel@vger.kernel.org,
        dri-devel@lists.freedesktop.org
References: <2c28c0a137854d39b6bc997a21bd6d2db1f7a0a5.1687423204.git.geert+renesas@glider.be>
From:   Sui Jingfeng <suijingfeng@loongson.cn>
Organization: Loongson
In-Reply-To: <2c28c0a137854d39b6bc997a21bd6d2db1f7a0a5.1687423204.git.geert+renesas@glider.be>
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Precedence: bulk

Hi

On 2023/6/22 17:21, Geert Uytterhoeven wrote:
> When the device is unbound from the driver, the display may be active.
> Make sure it gets shut down.

would you mind to give a short description why this is necessary.

> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
> ---
>   drivers/gpu/drm/renesas/shmobile/shmob_drm_drv.c | 2 ++
>   1 file changed, 2 insertions(+)
>
> diff --git a/drivers/gpu/drm/renesas/shmobile/shmob_drm_drv.c b/drivers/gpu/drm/renesas/shmobile/shmob_drm_drv.c
> index a29c0c1093725b6e..636f1888b815579b 100644
> --- a/drivers/gpu/drm/renesas/shmobile/shmob_drm_drv.c
> +++ b/drivers/gpu/drm/renesas/shmobile/shmob_drm_drv.c
> @@ -16,6 +16,7 @@
>   #include <linux/pm_runtime.h>
>   #include <linux/slab.h>
>   
> +#include <drm/drm_crtc_helper.h>
>   #include <drm/drm_drv.h>
>   #include <drm/drm_fbdev_generic.h>
>   #include <drm/drm_gem_dma_helper.h>
> @@ -145,6 +146,7 @@ static int shmob_drm_remove(struct platform_device *pdev)
>   	struct drm_device *ddev = &sdev->ddev;
>   
>   	drm_dev_unregister(ddev);
> +	drm_helper_force_disable_all(ddev);
Is it that the DRM core recommend us to use 
drm_atomic_helper_disable_all() ?
>   	drm_kms_helper_poll_fini(ddev);
>   	return 0;
>   }

-- 
Jingfeng