Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Date:   Mon, 1 Jul 2019 00:17:26 +0300
From:   Laurent Pinchart <laurent.pinchart@ideasonboard.com>
To:     Rob Clark <robdclark@gmail.com>
Cc:     dri-devel@lists.freedesktop.org, linux-arm-msm@vger.kernel.org,
        freedreno@lists.freedesktop.org, aarch64-laptops@lists.linaro.org,
        Rob Clark <robdclark@chromium.org>,
        Andrzej Hajda <a.hajda@samsung.com>,
        David Airlie <airlied@linux.ie>,
        Daniel Vetter <daniel@ffwll.ch>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 4/4] drm/bridge: ti-sn65dsi86: use helper to lookup
 panel-id
Message-ID: <20190630211726.GJ7043@pendragon.ideasonboard.com>
References: <20190630203614.5290-1-robdclark@gmail.com>
 <20190630203614.5290-5-robdclark@gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Disposition: inline
In-Reply-To: <20190630203614.5290-5-robdclark@gmail.com>
User-Agent: Mutt/1.10.1 (2018-07-13)
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

Hi Rob,

Thank you for the patch.

On Sun, Jun 30, 2019 at 01:36:08PM -0700, Rob Clark wrote:
> From: Rob Clark <robdclark@chromium.org>
> 
> Use the drm_of_find_panel_id() helper to decide which endpoint to use
> when looking up panel.  This way we can support devices that have
> multiple possible panels, such as the aarch64 laptops.
> 
> Signed-off-by: Rob Clark <robdclark@chromium.org>
> ---
>  drivers/gpu/drm/bridge/ti-sn65dsi86.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/bridge/ti-sn65dsi86.c b/drivers/gpu/drm/bridge/ti-sn65dsi86.c
> index 2719d9c0864b..56c66a43f1a6 100644
> --- a/drivers/gpu/drm/bridge/ti-sn65dsi86.c
> +++ b/drivers/gpu/drm/bridge/ti-sn65dsi86.c
> @@ -790,7 +790,7 @@ static int ti_sn_bridge_probe(struct i2c_client *client,
>  			      const struct i2c_device_id *id)
>  {
>  	struct ti_sn_bridge *pdata;
> -	int ret;
> +	int ret, panel_id;
>  
>  	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
>  		DRM_ERROR("device doesn't support I2C\n");
> @@ -811,7 +811,8 @@ static int ti_sn_bridge_probe(struct i2c_client *client,
>  
>  	pdata->dev = &client->dev;
>  
> -	ret = drm_of_find_panel_or_bridge(pdata->dev->of_node, 1, 0,
> +	panel_id = drm_of_find_panel_id();
> +	ret = drm_of_find_panel_or_bridge(pdata->dev->of_node, 1, panel_id,
>  					  &pdata->panel, NULL);
>  	if (ret) {
>  		DRM_ERROR("could not find any panel node\n");

No, I'm sorry, but that's a no-go. We can't patch every single bridge
driver to support this hack. We need a solution implemented at another
level that will not spread throughout the whole subsystem.

-- 
Regards,

Laurent Pinchart