Re: [PATCH v11 05/10] drm/mediatek: Add MT8195 Embedded DisplayPort driver

From: CK Hu
Date: Mon Jun 20 2022 - 02:49:59 EST


Hi, Bo-Chen:

On Fri, 2022-06-10 at 18:55 +0800, Bo-Chen Chen wrote:
> From: Markus Schneider-Pargmann <msp@xxxxxxxxxxxx>
>
> This patch adds a embedded displayport driver for the MediaTek mt8195
> SoC.
>
> It supports the MT8195, the embedded DisplayPort units. It offers
> DisplayPort 1.4 with up to 4 lanes.
>
> The driver creates a child device for the phy. The child device will
> never exist without the parent being active. As they are sharing a
> register range, the parent passes a regmap pointer to the child so
> that
> both can work with the same register range. The phy driver sets
> device
> data that is read by the parent to get the phy device that can be
> used
> to control the phy properties.
>
> This driver is based on an initial version by
> Jitao shi <jitao.shi@xxxxxxxxxxxx>
>
> Signed-off-by: Markus Schneider-Pargmann <msp@xxxxxxxxxxxx>
> Signed-off-by: Guillaume Ranquet <granquet@xxxxxxxxxxxx>
> [Bo-Chen: Cleanup the drivers and modify comments from reviewers]
> Signed-off-by: Bo-Chen Chen <rex-bc.chen@xxxxxxxxxxxx>
> ---

[snip]

> +
> +static int mtk_dp_probe(struct platform_device *pdev)
> +{
> + struct mtk_dp *mtk_dp;
> + struct device *dev = &pdev->dev;
> + int ret;
> + int irq_num = 0;
> +
> + mtk_dp = devm_kzalloc(dev, sizeof(*mtk_dp), GFP_KERNEL);
> + if (!mtk_dp)
> + return -ENOMEM;
> +
> + mtk_dp->dev = dev;
> +
> + irq_num = platform_get_irq(pdev, 0);
> + if (irq_num < 0)
> + return dev_err_probe(dev, irq_num,
> + "failed to request dp irq
> resource\n");
> +
> + mtk_dp->next_bridge = devm_drm_of_get_bridge(dev, dev->of_node,
> 1, 0);
> + if (IS_ERR(mtk_dp->next_bridge))
> + return dev_err_probe(dev, PTR_ERR(mtk_dp->next_bridge),
> + "Failed to get bridge\n");
> +
> + ret = mtk_dp_dt_parse(mtk_dp, pdev);
> + if (ret)
> + return dev_err_probe(dev, ret, "Failed to parse dt\n");
> +
> + drm_dp_aux_init(&mtk_dp->aux);
> + mtk_dp->aux.name = "aux_mtk_dp";
> + mtk_dp->aux.transfer = mtk_dp_aux_transfer;

In the comment of drm_dp_aux_init(), drm_dp_aux_init() is used before
drm_dp_aux_register(). So I think we still need to call
drm_dp_aux_register().

Regards,
CK

> +
> + ret = devm_request_threaded_irq(dev, irq_num, mtk_dp_hpd_event,
> + mtk_dp_hpd_event_thread,
> + IRQ_TYPE_LEVEL_HIGH,
> dev_name(dev),
> + mtk_dp);
> + if (ret)
> + return dev_err_probe(dev, -EPROBE_DEFER,
> + "failed to request mediatek dptx
> irq\n");
> +
> + mutex_init(&mtk_dp->dp_lock);
> +
> + platform_set_drvdata(pdev, mtk_dp);
> +
> + mtk_dp->phy_dev = platform_device_register_data(dev, "mediatek-
> dp-phy",
> + PLATFORM_DEVID_
> AUTO,
> + &mtk_dp->regs,
> + sizeof(struct
> regmap *));
> + if (IS_ERR(mtk_dp->phy_dev))
> + return dev_err_probe(dev, PTR_ERR(mtk_dp->phy_dev),
> + "Failed to create device mediatek-
> dp-phy\n");
> +
> + mtk_dp_get_calibration_data(mtk_dp);
> +
> + mtk_dp->phy = devm_phy_get(&mtk_dp->phy_dev->dev, "dp");
> +
> + if (IS_ERR(mtk_dp->phy)) {
> + platform_device_unregister(mtk_dp->phy_dev);
> + return dev_err_probe(dev, PTR_ERR(mtk_dp->phy),
> + "Failed to get phy\n");
> + }
> +
> + mtk_dp->bridge.funcs = &mtk_dp_bridge_funcs;
> + mtk_dp->bridge.of_node = dev->of_node;
> +
> + mtk_dp->bridge.ops =
> + DRM_BRIDGE_OP_DETECT | DRM_BRIDGE_OP_EDID |
> DRM_BRIDGE_OP_HPD;
> + mtk_dp->bridge.type = DRM_MODE_CONNECTOR_eDP;
> +
> + drm_bridge_add(&mtk_dp->bridge);
> +
> + pm_runtime_enable(dev);
> + pm_runtime_get_sync(dev);
> +
> + return 0;
> +}