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

[Marek Vasut]

On 7/10/23 17:26, Tim Harvey wrote:
> On Sat, Jul 8, 2023 at 1:55 PM Marek Vasut <marex at denx.de> wrote:
>>
>> 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;
> 
> Hi Marek,
> 
> No, the usage of it is within an 'if (CONFIG_IS_ENABLED(DM_REGULATOR)
> && imx_phy->vbus_supply)' statement

Except if this is not ifdef'd out, the structure is larger for no good 
reason if DM_REGULATOR is DISABLED.

>>>    };
>>>
>>>    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.
> 
> it does get disabled in imx8mq_usb_phy_power_off()

If that called if power_on returns -ERRNO ?

>> This likely needs a fail path with "err: ... return ret;"
> 
> there are no further conditional return paths in this function.

I suspect there should be.

>>> +                     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() .
> 
> Ok, I will send a v3 with that.

Thanks !