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Date:   Wed, 1 Nov 2023 15:59:51 +0200
From:   Laurent Pinchart <laurent.pinchart@ideasonboard.com>
To:     Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Cc:     Aradhya Bhatia <a-bhatia1@ti.com>,
        Devarsh Thakkar <devarsht@ti.com>,
        Jyri Sarha <jyri.sarha@iki.fi>,
        Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
        Maxime Ripard <mripard@kernel.org>,
        Thomas Zimmermann <tzimmermann@suse.de>,
        David Airlie <airlied@gmail.com>,
        Daniel Vetter <daniel@ffwll.ch>,
        dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 05/10] drm/tidss: Return error value from from softreset
Message-ID: <20231101135951.GU12764@pendragon.ideasonboard.com>
References: <20231101-tidss-probe-v1-0-45149e0f9415@ideasonboard.com>
 <20231101-tidss-probe-v1-5-45149e0f9415@ideasonboard.com>
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In-Reply-To: <20231101-tidss-probe-v1-5-45149e0f9415@ideasonboard.com>
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Hi Tomi,

Thank you for the patch.

On Wed, Nov 01, 2023 at 11:17:42AM +0200, Tomi Valkeinen wrote:
> Return an error value from dispc_softreset() so that the caller can
> handle the errors.
> 
> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
> ---
>  drivers/gpu/drm/tidss/tidss_dispc.c | 17 ++++++++++++-----
>  1 file changed, 12 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/gpu/drm/tidss/tidss_dispc.c b/drivers/gpu/drm/tidss/tidss_dispc.c
> index 9430625e2d62..cdbb88289082 100644
> --- a/drivers/gpu/drm/tidss/tidss_dispc.c
> +++ b/drivers/gpu/drm/tidss/tidss_dispc.c
> @@ -2702,7 +2702,7 @@ static void dispc_init_errata(struct dispc_device *dispc)
>  	}
>  }
>  
> -static void dispc_softreset(struct dispc_device *dispc)
> +static int dispc_softreset(struct dispc_device *dispc)
>  {
>  	u32 val;
>  	int ret;
> @@ -2712,8 +2712,12 @@ static void dispc_softreset(struct dispc_device *dispc)
>  	/* Wait for reset to complete */
>  	ret = readl_poll_timeout(dispc->base_common + DSS_SYSSTATUS,
>  				 val, val & 1, 100, 5000);
> -	if (ret)
> -		dev_warn(dispc->dev, "failed to reset dispc\n");
> +	if (ret) {
> +		dev_err(dispc->dev, "failed to reset dispc\n");
> +		return ret;
> +	}
> +
> +	return 0;
>  }
>  
>  int dispc_init(struct tidss_device *tidss)
> @@ -2828,8 +2832,11 @@ int dispc_init(struct tidss_device *tidss)
>  	tidss->dispc = dispc;
>  
>  	/* K2G display controller does not support soft reset */
> -	if (feat->subrev != DISPC_K2G)
> -		dispc_softreset(dispc);
> +	if (feat->subrev != DISPC_K2G) {
> +		r = dispc_softreset(dispc);
> +		if (r)
> +			return r;

tidss->dispc will be set in this case. Could that cause problems ?

> +	}
>  
>  	return 0;
>  }
> 

-- 
Regards,

Laurent Pinchart