Re: [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 <ma...@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 <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;

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 !