[PATCH v4] phy: phy-imx8mq-usb: add vbus regulator support

[Tim Harvey]

On Wed, Jul 12, 2023 at 2:15 AM Marek Vasut <marex at denx.de> wrote:
>
> On 7/11/23 22:13, Tim Harvey wrote:
> > On Mon, Jul 10, 2023 at 4:18 PM Marek Vasut <marex at denx.de> wrote:
> >>
> >> On 7/11/23 00:49, 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>
> >>> Reviewed-by: Marek Vasut <marex at denx.de>
> >>> ---
> >>> v4:
> >>>    - use regulator_set_enable_if_allowed to handle regulator reference counting
> >>>      errors
> >>>    - added Marek's rb tag
> >>>
> >>> v3:
> >>>    - change pr_err to dev_err
> >>>    - add #if CONFIG_IS_ENABLED around vbus_supply in struct
> >>>    - add fail path to disable clock if regulator enable failed
> >>>
> >>> 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 | 39 ++++++++++++++++++++++++++++++++++--
> >>>    1 file changed, 37 insertions(+), 2 deletions(-)
> >>>
> >>> diff --git a/drivers/phy/phy-imx8mq-usb.c b/drivers/phy/phy-imx8mq-usb.c
> >>> index 69f01de55538..6cbcb2338cfe 100644
> >>> --- a/drivers/phy/phy-imx8mq-usb.c
> >>> +++ b/drivers/phy/phy-imx8mq-usb.c
> >>> @@ -14,6 +14,8 @@
> >>>    #include <linux/delay.h>
> >>>    #include <linux/err.h>
> >>>    #include <clk.h>
> >>> +#include <dm/device_compat.h>
> >>> +#include <power/regulator.h>
> >>>
> >>>    #define PHY_CTRL0                   0x0
> >>>    #define PHY_CTRL0_REF_SSP_EN                BIT(2)
> >>> @@ -81,6 +83,9 @@ struct imx8mq_usb_phy {
> >>>    #endif
> >>>        void __iomem *base;
> >>>        enum imx8mpq_phy_type type;
> >>> +#if CONFIG_IS_ENABLED(DM_REGULATOR)
> >>> +     struct udevice *vbus_supply;
> >>> +#endif
> >>>    };
> >>>
> >>>    static const struct udevice_id imx8mq_usb_phy_of_match[] = {
> >>> @@ -172,10 +177,10 @@ 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");
> >>> @@ -183,18 +188,31 @@ 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_if_allowed(imx_phy->vbus_supply, true);
> >>> +             if (ret && ret != -ENOSYS) {
> >>> +                     dev_err(dev, "Failed to enable VBUS regulator: %d\n", ret);
> >>> +                     goto err;
> >>> +             }
> >>> +     }
> >>> +
> >>>        /* Disable rx term override */
> >>>        value = readl(imx_phy->base + PHY_CTRL6);
> >>>        value &= ~PHY_CTRL6_RXTERM_OVERRIDE_SEL;
> >>>        writel(value, imx_phy->base + PHY_CTRL6);
> >>>
> >>>        return 0;
> >>> +
> >>> +err:
> >>> +     clk_disable(&imx_phy->phy_clk);
> >>> +     return ret;
> >>>    }
> >>>
> >>>    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 +224,14 @@ 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_if_allowed(imx_phy->vbus_supply, false);
> >>> +             if (ret && ret != -ENOSYS) {
> >>> +                     dev_err(dev, "Failed to disable VBUS regulator: %d\n", ret);
> >>> +                     return ret;
> >>> +             }
> >>> +     }
> >>> +
> >>>        return 0;
> >>>    }
> >>>
> >>> @@ -224,6 +250,7 @@ struct phy_ops imx8mq_usb_phy_ops = {
> >>>    int imx8mq_usb_phy_probe(struct udevice *dev)
> >>>    {
> >>>        struct imx8mq_usb_phy *priv = dev_get_priv(dev);
> >>> +     __maybe_unused int ret;
> >>>
> >>>        priv->type = dev_get_driver_data(dev);
> >>>        priv->base = dev_read_addr_ptr(dev);
> >>> @@ -232,7 +259,6 @@ int imx8mq_usb_phy_probe(struct udevice *dev)
> >>>                return -EINVAL;
> >>>
> >>>    #if CONFIG_IS_ENABLED(CLK)
> >>> -     int ret;
> >>
> >> I _think_ if you were to convert this #if CONFIG...() to if
> >> (CONFIG...()), you would be able to drop the __maybe_unused . Separate
> >> conversion patch would be better though.
> >
> > Hi Marek,
>
> Hi,
>
> > Yes, I thought about that as well and felt it should be a separate
> > followup cleanup patch.
>
> Can you please send such a follow up patch ?
>

Yes, I'll send a follow-up today. It looks like Stefano is picking
this up from the imx tree... is that where it should be picked up or
should this be through you and the usb tree?

Tim