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

[Marek Vasut]

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 ?

Thanks