Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Thu, 2 Jun 2022 17:20:28 +0300
From:   Laurent Pinchart <laurent.pinchart@ideasonboard.com>
To:     Jiasheng Jiang <jiasheng@iscas.ac.cn>
Cc:     andrzej.hajda@intel.com, narmstrong@baylibre.com,
        robert.foss@linaro.org, jonas@kwiboo.se, jernej.skrabec@gmail.com,
        airlied@linux.ie, daniel@ffwll.ch, maxime@cerno.tech,
        sam@ravnborg.org, alsi@bang-olufsen.dk, jagan@amarulasolutions.com,
        biju.das.jz@bp.renesas.com, l.stach@pengutronix.de,
        dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2] drm: bridge: adv7511: Add check for
 mipi_dsi_driver_register
Message-ID: <YpjHLN2U8DOh9NLH@pendragon.ideasonboard.com>
References: <20220602103401.2980938-1-jiasheng@iscas.ac.cn>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Disposition: inline
In-Reply-To: <20220602103401.2980938-1-jiasheng@iscas.ac.cn>
Precedence: bulk

Hi Jiasheng,

Thank you for the patch.

On Thu, Jun 02, 2022 at 06:34:01PM +0800, Jiasheng Jiang wrote:
> As mipi_dsi_driver_register could return error if fails,
> it should be better to check the return value and return error
> if fails.
> Moreover, if i2c_add_driver fails,  mipi_dsi_driver_register
> should be reverted.
> 
> Fixes: 1e4d58cd7f88 ("drm/bridge: adv7533: Create a MIPI DSI device")
> Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>

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

> ---
> Changelog:
> 
> v1 -> v2
> 
> *Change 1. Add the mipi_dsi_driver_unregister if i2c_add_driver fails.
> ---
>  drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 17 ++++++++++++++---
>  1 file changed, 14 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
> index 5bb9300040dd..2275d15d4a8b 100644
> --- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
> +++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
> @@ -1392,10 +1392,21 @@ static struct i2c_driver adv7511_driver = {
>  
>  static int __init adv7511_init(void)
>  {
> -	if (IS_ENABLED(CONFIG_DRM_MIPI_DSI))
> -		mipi_dsi_driver_register(&adv7533_dsi_driver);
> +	int ret;
> +
> +	if (IS_ENABLED(CONFIG_DRM_MIPI_DSI)) {
> +		ret = mipi_dsi_driver_register(&adv7533_dsi_driver);
> +		if (ret)
> +			return ret;
> +	}
>  
> -	return i2c_add_driver(&adv7511_driver);
> +	ret = i2c_add_driver(&adv7511_driver);
> +	if (ret) {
> +		if (IS_ENABLED(CONFIG_DRM_MIPI_DSI))
> +			mipi_dsi_driver_unregister(&adv7533_dsi_driver);
> +	}
> +
> +	return ret;
>  }
>  module_init(adv7511_init);
>  

-- 
Regards,

Laurent Pinchart