[PATCH v5] phy: phy-imx8mq-usb: add vbus regulator support

[Tim Harvey]

On Wed, Jul 12, 2023 at 6:55 PM Marek Vasut <marex at denx.de> wrote:
>
> On 7/13/23 02:40, 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.
> >
> > While we are at it replace '#if CONFIG_IS_ENABLED(CLK)' with
> > 'if (CONFIG_IS_ENABLED(CLK))' as a cleanup.
> >
> > 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>
> > ---
> > v5:
> >   - remove #if CONFIG_IS_ENABLED around struct members
> >     (you can not conditionally include if using if (CONFIG_IS_ENABLED(foo)) )
> >   - replace clk '#if CONFIG_IS_ENABLED(CLK)' with 'if (CONFIG_IS_ENABLED(CLK))'
> >
> > 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 | 68 +++++++++++++++++++++++++-----------
> >   1 file changed, 48 insertions(+), 20 deletions(-)
> >
> > diff --git a/drivers/phy/phy-imx8mq-usb.c b/drivers/phy/phy-imx8mq-usb.c
> > index 69f01de55538..532b0235e2bc 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)
> > @@ -76,11 +78,10 @@ enum imx8mpq_phy_type {
> >   };
> >
> >   struct imx8mq_usb_phy {
> > -#if CONFIG_IS_ENABLED(CLK)
> >       struct clk phy_clk;
> > -#endif
> >       void __iomem *base;
> >       enum imx8mpq_phy_type type;
> > +     struct udevice *vbus_supply;
> >   };
> >
> >   static const struct udevice_id imx8mq_usb_phy_of_match[] = {
> > @@ -172,16 +173,24 @@ 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);
> > +     int ret;
> >       u32 value;
> >
>
> int ret; goes below u32 value (nitpick)
>
> > -#if CONFIG_IS_ENABLED(CLK)
> > -     int ret;
> > -     ret = clk_enable(&imx_phy->phy_clk);
> > -     if (ret) {
> > -             printf("Failed to enable usb phy clock\n");
> > -             return ret;
> > +     if (CONFIG_IS_ENABLED(CLK)) {
> > +             ret = clk_enable(&imx_phy->phy_clk);
> > +             if (ret) {
> > +                     printf("Failed to enable usb phy clock\n");
> > +                     return ret;
> > +             }
> > +     }
> > +
> > +     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;
> > +             }
> >       }
> > -#endif
> >
> >       /* Disable rx term override */
> >       value = readl(imx_phy->base + PHY_CTRL6);
> > @@ -189,12 +198,17 @@ static int imx8mq_usb_phy_power_on(struct phy *usb_phy)
> >       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);
> > +     int ret;
> >       u32 value;
>
> DTTO
>
> >       /* Override rx term to be 0 */
> > @@ -202,9 +216,16 @@ static int imx8mq_usb_phy_power_off(struct phy *usb_phy)
> >       value |= PHY_CTRL6_RXTERM_OVERRIDE_SEL;
> >       writel(value, imx_phy->base + PHY_CTRL6);
> >
> > -#if CONFIG_IS_ENABLED(CLK)
> > -     clk_disable(&imx_phy->phy_clk);
> > -#endif
> > +     if (CONFIG_IS_ENABLED(CLK))
> > +             clk_disable(&imx_phy->phy_clk);
>
> It would really be good to have this in two patches, i.e. the clock
> clean up first, and the regulator addition second.

ok, I'll submit a v5 with 2 patches then.

Note that the __maybe_unused from previous revisions will not be there
as is not needed as if (CONFIG_IS_ENABLED(foo)) is always compiled in.
All of these changes from '#ifdef' to 'if (CONFIG_IS_ENABLED)' is not
shrinking code.... I hope everyone understands that.

best regards,

Tim