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

[Marek Vasut]

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 <thar...@gateworks.com>
Reviewed-by: Adam Ford <aford...@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;
  };

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.
This likely needs a fail path with "err: ... return ret;"

+                       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() .

+                       return ret;
+               }
+       }
+
        return 0;
  }

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