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Message-ID: <f511c66b-10b3-0af1-3bb5-801060c3a55e@pengutronix.de>
Date:   Fri, 28 Jul 2023 14:21:19 +0200
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Subject: Re: [PATCH v3 3/3] drm/panel-simple: allow LVDS format override
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To:     Dan Carpenter <dan.carpenter@linaro.org>
Cc:     Neil Armstrong <neil.armstrong@linaro.org>,
        Conor Dooley <conor+dt@kernel.org>,
        Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>,
        Dan Carpenter <error27@gmail.com>,
        Daniel Vetter <daniel@ffwll.ch>, devicetree@vger.kernel.org,
        Sam Ravnborg <sam@ravnborg.org>, linux-kernel@vger.kernel.org,
        dri-devel@lists.freedesktop.org, Rob Herring <robh+dt@kernel.org>,
        Thierry Reding <thierry.reding@gmail.com>,
        Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        patchwork-jzi@pengutronix.de, David Airlie <airlied@gmail.com>,
        kernel@pengutronix.de, kernel test robot <lkp@intel.com>
References: <20230523-simplepanel_support_nondefault_datamapping-v3-0-78ede374d3d9@pengutronix.de>
 <20230523-simplepanel_support_nondefault_datamapping-v3-3-78ede374d3d9@pengutronix.de>
 <1cd00596-604d-4fbf-b9d1-9ee0f05cb373@kadam.mountain>
From:   Johannes Zink <j.zink@pengutronix.de>
In-Reply-To: <1cd00596-604d-4fbf-b9d1-9ee0f05cb373@kadam.mountain>
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Hi Dan,

thanks for your feedback.

On 7/28/23 14:03, Dan Carpenter wrote:
> On Fri, Jul 28, 2023 at 01:54:40PM +0200, Johannes Zink wrote:
>> @@ -556,7 +602,7 @@ static int panel_simple_probe(struct device *dev, const struct panel_desc *desc)
>>   	struct device_node *ddc;
>>   	int connector_type;
>>   	u32 bus_flags;
>> -	int err;
>> +	int err, ret;
> 
> I don't like this at all...
> 
>>   
>>   	panel = devm_kzalloc(dev, sizeof(*panel), GFP_KERNEL);
>>   	if (!panel)
>> @@ -601,6 +647,13 @@ static int panel_simple_probe(struct device *dev, const struct panel_desc *desc)
>>   			panel_simple_parse_panel_timing_node(dev, panel, &dt);
>>   	}
>>   
>> +	if (desc->connector_type == DRM_MODE_CONNECTOR_LVDS) {
>> +		/* Optional data-mapping property for overriding bus format */
>> +		ret = panel_simple_override_nondefault_lvds_datamapping(dev, panel);
>> +		if (ret)
>> +			goto free_ddc;
> 
> This *looks* like we are returning an error but we aren't.  I think we
> should be.  If not then we need to have a discussion about that and
> add some comments.
> 

Good catch. This should actually be err instead of ret. This way we'd make sure
to return -ENOMEM from panel_simple_probe() in case an error occured due
to devm_kmemdup failing in panel_simple_override_nondefault_lvds_datamapping().

I'll send a v4 with that fixed.

Thanks for having my back!
Johannes

> regards,
> dan carpenter
> 
>> +	}
>> +
>>   	connector_type = desc->connector_type;
>>   	/* Catch common mistakes for panels. */
>>   	switch (connector_type) {
>>
>> -- 
>> 2.39.2
> 
> 

-- 
Pengutronix e.K.                | Johannes Zink                  |
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