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Date: Mon, 13 May 2024 00:20:38 +0300
From: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
To: Sui Jingfeng <sui.jingfeng@linux.dev>
Cc: Maxime Ripard <mripard@kernel.org>,
	Andrzej Hajda <andrzej.hajda@intel.com>,
	Neil Armstrong <neil.armstrong@linaro.org>,
	Robert Foss <rfoss@kernel.org>, Jonas Karlman <jonas@kwiboo.se>,
	Jernej Skrabec <jernej.skrabec@gmail.com>,
	Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
	Thomas Zimmermann <tzimmermann@suse.de>,
	dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] drm/bridge: synopsys: dw-mipi-dsi: Remove a redundant
 check on existence of bridge->encoder
Message-ID: <20240512212038.GR17158@pendragon.ideasonboard.com>
References: <20240511144713.325156-1-sui.jingfeng@linux.dev>
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In-Reply-To: <20240511144713.325156-1-sui.jingfeng@linux.dev>

Hi Sui,

Thank you for the patch.

On Sat, May 11, 2024 at 10:47:13PM +0800, Sui Jingfeng wrote:
> In the dw_mipi_dsi_bridge_attach() function, the check on the existence
> of bridge->encoder is not necessary, as it has already been done in the
> drm_bridge_attach() function. And the check on the drm bridge core
> happens before check in the implementation. Hence, it is guaranteed that
> the .encoder member of the struct drm_bridge is not NULL when
> dw_mipi_dsi_bridge_attach() function gets called.
> 
> Remove the redundant checking codes "if (!bridge->encoder) { ... }".
> 
> Signed-off-by: Sui Jingfeng <sui.jingfeng@linux.dev>

Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

> ---
>  drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c | 5 -----
>  1 file changed, 5 deletions(-)
> 
> diff --git a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
> index 824fb3c65742..c4e9d96933dc 100644
> --- a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
> +++ b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
> @@ -1071,11 +1071,6 @@ static int dw_mipi_dsi_bridge_attach(struct drm_bridge *bridge,
>  {
>  	struct dw_mipi_dsi *dsi = bridge_to_dsi(bridge);
>  
> -	if (!bridge->encoder) {
> -		DRM_ERROR("Parent encoder object not found\n");
> -		return -ENODEV;
> -	}
> -
>  	/* Set the encoder type as caller does not know it */
>  	bridge->encoder->encoder_type = DRM_MODE_ENCODER_DSI;
>  

-- 
Regards,

Laurent Pinchart