Re: [PATCH 3/5] phy: tegra: xusb: Parse dual-role mode property

[jckuo]

Reviewed-by: JC Kuo <jckuo@xxxxxxxxxx>

On 1/25/19 7:25 PM, Thierry Reding wrote:
> From: Thierry Reding <treding@xxxxxxxxxx>
>
> The device tree bindings document the "mode" property of "ports"
> subnodes, but the driver was not parsing the property. In preparation
> for adding role switching, parse the property at probe time.
>
> Based on work by JC Kuo <jckuo@xxxxxxxxxx>.
>
> Signed-off-by: Thierry Reding <treding@xxxxxxxxxx>
> ---
>   drivers/phy/tegra/xusb.c | 21 +++++++++++++++++++++
>   drivers/phy/tegra/xusb.h |  3 +++
>   2 files changed, 24 insertions(+)
>
> diff --git a/drivers/phy/tegra/xusb.c b/drivers/phy/tegra/xusb.c
> index e3bc60cfe6a1..57a2d08ef6da 100644
> --- a/drivers/phy/tegra/xusb.c
> +++ b/drivers/phy/tegra/xusb.c
> @@ -546,13 +546,34 @@ static void tegra_xusb_port_unregister(struct tegra_xusb_port *port)
>   	device_unregister(&port->dev);
>   }
>   
> +static const char *const modes[] = {
> +	[USB_DR_MODE_UNKNOWN] = "",
> +	[USB_DR_MODE_HOST] = "host",
> +	[USB_DR_MODE_PERIPHERAL] = "peripheral",
> +	[USB_DR_MODE_OTG] = "otg",
> +};
> +
>   static int tegra_xusb_usb2_port_parse_dt(struct tegra_xusb_usb2_port *usb2)
>   {
>   	struct tegra_xusb_port *port = &usb2->base;
>   	struct device_node *np = port->dev.of_node;
> +	const char *mode;
>   
>   	usb2->internal = of_property_read_bool(np, "nvidia,internal");
>   
> +	if (!of_property_read_string(np, "mode", &mode)) {
> +		int err = match_string(modes, ARRAY_SIZE(modes), mode);
> +		if (err < 0) {
> +			dev_err(&port->dev, "invalid value %s for \"mode\"\n",
> +				mode);
> +			usb2->mode = USB_DR_MODE_UNKNOWN;
> +		} else {
> +			usb2->mode = err;
> +		}
> +	} else {
> +		usb2->mode = USB_DR_MODE_HOST;
> +	}
> +
>   	usb2->supply = devm_regulator_get(&port->dev, "vbus");
>   	return PTR_ERR_OR_ZERO(usb2->supply);
>   }
> diff --git a/drivers/phy/tegra/xusb.h b/drivers/phy/tegra/xusb.h
> index b49dbc36efa3..bb60fc09c752 100644
> --- a/drivers/phy/tegra/xusb.h
> +++ b/drivers/phy/tegra/xusb.h
> @@ -19,6 +19,8 @@
>   #include <linux/mutex.h>
>   #include <linux/workqueue.h>
>   
> +#include <linux/usb/otg.h>
> +
>   /* legacy entry points for backwards-compatibility */
>   int tegra_xusb_padctl_legacy_probe(struct platform_device *pdev);
>   int tegra_xusb_padctl_legacy_remove(struct platform_device *pdev);
> @@ -271,6 +273,7 @@ struct tegra_xusb_usb2_port {
>   	struct tegra_xusb_port base;
>   
>   	struct regulator *supply;
> +	enum usb_dr_mode mode;
>   	bool internal;
>   };
>