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

[Marek Vasut]

On 7/13/23 18:55, Tim Harvey wrote:
> 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.

I believe we are all in agreement, yes.