[PATCH v2] phy: phy-imx8mq-usb: add vbus regulator support

[Marek Vasut]

On 6/9/23 19:28, Tim Harvey wrote:
> Add support for enabling and disabling vbus-supply regulator found
> on several imx8mp boards in the usb3_phy0 and usb3_phy1 nodes.
> 
> Signed-off-by: Tim Harvey <tharvey at gateworks.com>
> Reviewed-by: Adam Ford <aford173 at gmail.com>
> ---
> v2:
>   - protect ret with __maybe_unused in case CONFIG_CLK and
>     CONFIG_DM_REGULATOR not defined
>   - add error prints on failures
>   - add Adam's rb tag
> ---
>   drivers/phy/phy-imx8mq-usb.c | 32 ++++++++++++++++++++++++++++++--
>   1 file changed, 30 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/phy/phy-imx8mq-usb.c b/drivers/phy/phy-imx8mq-usb.c
> index 69f01de55538..53099436b04b 100644
> --- a/drivers/phy/phy-imx8mq-usb.c
> +++ b/drivers/phy/phy-imx8mq-usb.c
> @@ -14,6 +14,7 @@
>   #include <linux/delay.h>
>   #include <linux/err.h>
>   #include <clk.h>
> +#include <power/regulator.h>
>   
>   #define PHY_CTRL0			0x0
>   #define PHY_CTRL0_REF_SSP_EN		BIT(2)
> @@ -81,6 +82,7 @@ struct imx8mq_usb_phy {
>   #endif
>   	void __iomem *base;
>   	enum imx8mpq_phy_type type;

Shouldn't this be in #if CONFIG_IS_ENABLED(DM_REGULATOR) ?

> +	struct udevice *vbus_supply;
>   };
>   
>   static const struct udevice_id imx8mq_usb_phy_of_match[] = {
> @@ -172,10 +174,10 @@ static int imx8mq_usb_phy_power_on(struct phy *usb_phy)
>   {
>   	struct udevice *dev = usb_phy->dev;
>   	struct imx8mq_usb_phy *imx_phy = dev_get_priv(dev);
> +	__maybe_unused int ret;
>   	u32 value;
>   
>   #if CONFIG_IS_ENABLED(CLK)
> -	int ret;
>   	ret = clk_enable(&imx_phy->phy_clk);
>   	if (ret) {
>   		printf("Failed to enable usb phy clock\n");
> @@ -183,6 +185,14 @@ static int imx8mq_usb_phy_power_on(struct phy *usb_phy)
>   	}
>   #endif
>   
> +	if (CONFIG_IS_ENABLED(DM_REGULATOR) && imx_phy->vbus_supply) {
> +		ret = regulator_set_enable(imx_phy->vbus_supply, true);
> +		if (ret) {
> +			pr_err("Failed to enable VBUS regulator: %d\n", ret);

You do need to disable clock enabled above.
This likely needs a fail path with "err: ... return ret;"

> +			return ret;
> +		}
> +	}
> +
>   	/* Disable rx term override */
>   	value = readl(imx_phy->base + PHY_CTRL6);
>   	value &= ~PHY_CTRL6_RXTERM_OVERRIDE_SEL;
> @@ -195,6 +205,7 @@ static int imx8mq_usb_phy_power_off(struct phy *usb_phy)
>   {
>   	struct udevice *dev = usb_phy->dev;
>   	struct imx8mq_usb_phy *imx_phy = dev_get_priv(dev);
> +	__maybe_unused int ret;
>   	u32 value;
>   
>   	/* Override rx term to be 0 */
> @@ -206,6 +217,14 @@ static int imx8mq_usb_phy_power_off(struct phy *usb_phy)
>   	clk_disable(&imx_phy->phy_clk);
>   #endif
>   
> +	if (CONFIG_IS_ENABLED(DM_REGULATOR) && imx_phy->vbus_supply) {
> +		ret = regulator_set_enable(imx_phy->vbus_supply, false);
> +		if (ret) {
> +			pr_err("Failed to disable VBUS regulator: %d\n", ret);

btw with DM, these can be dev_err() .

> +			return ret;
> +		}
> +	}
> +
>   	return 0;
>   }
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