Re: [PATCH 09/11] drm/tegra: convert to struct drm_edid

[Daniel Vetter <daniel@ffwll.ch>]

On Tue, May 14, 2024 at 03:55:15PM +0300, Jani Nikula wrote:
> Prefer the struct drm_edid based functions for reading the EDID and
> updating the connector.
> 
> Signed-off-by: Jani Nikula <jani.nikula@intel.com>
> 
> ---
> 
> Cc: Thierry Reding <thierry.reding@gmail.com>
> Cc: Mikko Perttunen <mperttunen@nvidia.com>
> Cc: Jonathan Hunter <jonathanh@nvidia.com>
> Cc: linux-tegra@vger.kernel.org
> ---
>  drivers/gpu/drm/tegra/drm.h    |  2 +-
>  drivers/gpu/drm/tegra/output.c | 29 +++++++++++++++++------------
>  2 files changed, 18 insertions(+), 13 deletions(-)
> 
> diff --git a/drivers/gpu/drm/tegra/drm.h b/drivers/gpu/drm/tegra/drm.h
> index 682011166a8f..2f3781e04b0a 100644
> --- a/drivers/gpu/drm/tegra/drm.h
> +++ b/drivers/gpu/drm/tegra/drm.h
> @@ -133,7 +133,7 @@ struct tegra_output {
>  	struct drm_bridge *bridge;
>  	struct drm_panel *panel;
>  	struct i2c_adapter *ddc;
> -	const struct edid *edid;
> +	const struct drm_edid *drm_edid;
>  	struct cec_notifier *cec;
>  	unsigned int hpd_irq;
>  	struct gpio_desc *hpd_gpio;
> diff --git a/drivers/gpu/drm/tegra/output.c b/drivers/gpu/drm/tegra/output.c
> index 4da3c3d1abbc..e6b5863fec71 100644
> --- a/drivers/gpu/drm/tegra/output.c
> +++ b/drivers/gpu/drm/tegra/output.c
> @@ -21,7 +21,7 @@
>  int tegra_output_connector_get_modes(struct drm_connector *connector)
>  {
>  	struct tegra_output *output = connector_to_output(connector);
> -	struct edid *edid = NULL;
> +	const struct drm_edid *drm_edid;
>  	int err = 0;
>  
>  	/*
> @@ -34,18 +34,17 @@ int tegra_output_connector_get_modes(struct drm_connector *connector)
>  			return err;
>  	}
>  
> -	if (output->edid)
> -		edid = kmemdup(output->edid, sizeof(*edid), GFP_KERNEL);
> +	if (output->drm_edid)
> +		drm_edid = drm_edid_dup(output->drm_edid);
>  	else if (output->ddc)
> -		edid = drm_get_edid(connector, output->ddc);
> +		drm_edid = drm_edid_read_ddc(connector, output->ddc);

Annoyingly the dsi output is the only one not using
drm_connector_init_with_ddc() despite that I think it could, so we can't
yet use drm_edid_read here ...

>  
> -	cec_notifier_set_phys_addr_from_edid(output->cec, edid);
> -	drm_connector_update_edid_property(connector, edid);
> +	drm_edid_connector_update(connector, drm_edid);
> +	cec_notifier_set_phys_addr(output->cec,
> +				   connector->display_info.source_physical_address);
>  
> -	if (edid) {
> -		err = drm_add_edid_modes(connector, edid);
> -		kfree(edid);
> -	}
> +	err = drm_edid_connector_add_modes(connector);
> +	drm_edid_free(drm_edid);
>  
>  	return err;
>  }
> @@ -98,6 +97,7 @@ static irqreturn_t hpd_irq(int irq, void *data)
>  int tegra_output_probe(struct tegra_output *output)
>  {
>  	struct device_node *ddc, *panel;
> +	const void *edid;
>  	unsigned long flags;
>  	int err, size;
>  
> @@ -124,8 +124,6 @@ int tegra_output_probe(struct tegra_output *output)
>  			return PTR_ERR(output->panel);
>  	}
>  
> -	output->edid = of_get_property(output->of_node, "nvidia,edid", &size);
> -

I think you can/should also delete tegra_output.edid completely, since not
doing that freaked me out a bit until I checked everything :-) At least if
I didn't git grep the wrong regex.

With that bikeshed addressed:

Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

>  	ddc = of_parse_phandle(output->of_node, "nvidia,ddc-i2c-bus", 0);
>  	if (ddc) {
>  		output->ddc = of_get_i2c_adapter_by_node(ddc);
> @@ -137,6 +135,9 @@ int tegra_output_probe(struct tegra_output *output)
>  		}
>  	}
>  
> +	edid = of_get_property(output->of_node, "nvidia,edid", &size);
> +	output->drm_edid = drm_edid_alloc(edid, size);
> +
>  	output->hpd_gpio = devm_fwnode_gpiod_get(output->dev,
>  					of_fwnode_handle(output->of_node),
>  					"nvidia,hpd",
> @@ -187,6 +188,8 @@ int tegra_output_probe(struct tegra_output *output)
>  	if (output->ddc)
>  		i2c_put_adapter(output->ddc);
>  
> +	drm_edid_free(output->drm_edid);
> +
>  	return err;
>  }
>  
> @@ -197,6 +200,8 @@ void tegra_output_remove(struct tegra_output *output)
>  
>  	if (output->ddc)
>  		i2c_put_adapter(output->ddc);
> +
> +	drm_edid_free(output->drm_edid);
>  }
>  
>  int tegra_output_init(struct drm_device *drm, struct tegra_output *output)
> -- 
> 2.39.2
> 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch