2023-07-28 12:15:13

by Dan Carpenter

Subject: Re: [PATCH v3 3/3] drm/panel-simple: allow LVDS format override

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.

regards,
dan carpenter

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

2023-07-28 13:36:04

by Johannes Zink

Subject: Re: [PATCH v3 3/3] drm/panel-simple: allow LVDS format override

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
>
>

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