Subject: Re: [PATCH v3 3/3] drm/bridge/synopsys: dsi: explicitly request
 exclusive reset control
To: Philippe CORNU <philippe.cornu@st.com>,
        Archit Taneja <architt@codeaurora.org>,
        Laurent Pinchart <Laurent.pinchart@ideasonboard.com>,
        David Airlie <airlied@linux.ie>,
        Philipp Zabel <p.zabel@pengutronix.de>,
        dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org
Cc: Yannick Fertre <yannick.fertre@st.com>,
        Benjamin Gaignard <benjamin.gaignard@linaro.org>,
        Vincent Abriou <vincent.abriou@st.com>,
        Alexandre Torgue <alexandre.torgue@st.com>,
        Maxime Coquelin <mcoquelin.stm32@gmail.com>,
        Gabriel Fernandez <gabriel.fernandez@st.com>,
        Ludovic Barre <ludovic.barre@st.com>,
        Fabien Dessenne <fabien.dessenne@st.com>,
        Mickael Reulier <mickael.reulier@st.com>
From: Andrzej Hajda <a.hajda@samsung.com>
Message-id: <c531303a-7cd7-b705-f9a1-fb6ec18b3818@samsung.com>
Date: Fri, 01 Sep 2017 15:45:09 +0200
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On 01.08.2017 15:23, Philippe CORNU wrote:
> Based on patch "Convert drivers to explicit reset API" from Philipp Zabel
>
> Commit a53e35db70d1 ("reset: Ensure drivers are explicit when requesting
> reset lines") started to transition the reset control request API calls
> to explicitly state whether the driver needs exclusive or shared reset
> control behavior. Convert all drivers requesting exclusive resets to the
> explicit API call so the temporary transition helpers can be removed.
>
> No functional changes.
>
> Cc: Philipp Zabel <p.zabel@pengutronix.de>
> Signed-off-by: Philippe CORNU <philippe.cornu@st.com>
> Acked-by: Philipp Zabel <p.zabel@pengutronix.de>
> ---
>  drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c | 10 +++-------
>  1 file changed, 3 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
> index 781340d..4e1f91e 100644
> --- a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
> +++ b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
> @@ -885,15 +885,11 @@ static int dw_mipi_dsi_bridge_attach(struct drm_bridge *bridge)
>  	 * Note that the reset was not defined in the initial device tree, so
>  	 * we have to be prepared for it not being found.
>  	 */
> -	apb_rst = devm_reset_control_get(dev, "apb");
> +	apb_rst = devm_reset_control_get_optional_exclusive(dev, "apb");
>  	if (IS_ERR(apb_rst)) {
>  		ret = PTR_ERR(apb_rst);
> -		if (ret == -ENOENT) {
> -			apb_rst = NULL;
> -		} else {
> -			dev_err(dev, "Unable to get reset control: %d\n", ret);
> -			return ERR_PTR(ret);
> -		}
> +		dev_err(dev, "Unable to get reset control: %d\n", ret);

I think in case of deferred probing it shouldn't be dev_err, but this is
rather suggestion.

> +		return ERR_PTR(ret);
  
return apb_rst;

With this fixed:
Reviewed-by: Andrzej Hajda <a.hajda@samsung.com>

 --
Regards
Andrzej

>  	}
>  
>  	if (apb_rst) {