Re: [PATCH 2/5] drm/bridge: simple-bridge: Extend match support for non-DT based systems

From: Laurent Pinchart
Date: Mon Jan 22 2024 - 21:12:15 EST


On Tue, Jan 23, 2024 at 12:32:17AM +0800, Sui Jingfeng wrote:
> Which is intended to be used on non-DT environment, where the simple-bridge
> platform device is created by either the display controller driver side or
> platform firmware subsystem.

Could you give an example of a platform where you intend to use this ?

> To avoid duplication and to keep consistent,
> we choose to reuse the OF match tables. Because the potentional user may
> not has a of_node attached, nor a ACPI match id. If this is the case,
> a software node string property can be provide to fill the niche.

Shouldn't non-DT, non-ACPI platforms use swnodes ?

> Signed-off-by: Sui Jingfeng <sui.jingfeng@xxxxxxxxx>
> ---
> drivers/gpu/drm/bridge/simple-bridge.c | 24 +++++++++++++++++++++++-
> 1 file changed, 23 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/bridge/simple-bridge.c b/drivers/gpu/drm/bridge/simple-bridge.c
> index cbe8e778d7c7..595f672745b9 100644
> --- a/drivers/gpu/drm/bridge/simple-bridge.c
> +++ b/drivers/gpu/drm/bridge/simple-bridge.c
> @@ -166,6 +166,24 @@ static const struct drm_bridge_funcs simple_bridge_bridge_funcs = {
> .disable = simple_bridge_disable,
> };
>
> +static const void *simple_bridge_get_match_data(const struct device *dev)
> +{
> + const struct of_device_id *matches = dev->driver->of_match_table;
> +
> + /* Try to get the match data by software node */
> + while (matches) {
> + if (!matches->compatible[0])
> + break;
> +
> + if (device_is_compatible(dev, matches->compatible))
> + return matches->data;
> +
> + matches++;
> + }
> +
> + return NULL;
> +}
> +
> static int simple_bridge_probe(struct platform_device *pdev)
> {
> struct simple_bridge *sbridge;
> @@ -176,7 +194,10 @@ static int simple_bridge_probe(struct platform_device *pdev)
> return -ENOMEM;
> platform_set_drvdata(pdev, sbridge);
>
> - sbridge->info = of_device_get_match_data(&pdev->dev);
> + if (pdev->dev.of_node)
> + sbridge->info = of_device_get_match_data(&pdev->dev);
> + else
> + sbridge->info = simple_bridge_get_match_data(&pdev->dev);
>
> /* Get the next bridge in the pipeline. */
> remote = of_graph_get_remote_node(pdev->dev.of_node, 1, -1);
> @@ -309,3 +330,4 @@ module_platform_driver(simple_bridge_driver);
> MODULE_AUTHOR("Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx>");
> MODULE_DESCRIPTION("Simple DRM bridge driver");
> MODULE_LICENSE("GPL");
> +MODULE_ALIAS("platform:simple-bridge");

This is an unrelated change.

--
Regards,

Laurent Pinchart