Hi Martin

On Fri, 18 Jun 2021 at 03:54, Martin Blumenstingl
[off-list ref] wrote:

Hi Anand,

On Thu, Jun 17, 2021 at 9:44 PM Anand Moon [off-list ref] wrote:
[...]

quoted

+static int phy_meson8b_usb2_reset(struct phy *phy)
+{
+       struct phy_meson8b_usb2_priv *priv = phy_get_drvdata(phy);
+       int ret;
+
+       if (priv->is_enabled) {
+               ret = reset_control_reset(priv->reset);
+               if (ret) {
+                       dev_err(&phy->dev, "Failed to trigger USB reset\n");
+                       return ret;
+               }
+       }
+
+       return 0;
+}

will this reset change the register values back to some kind of default?
If it does then we're not re-applying our desired register values
afterwards - which is probably asking for trouble.

For shared resets (like the one we have here) reset_control_reset will
only trigger the reset line once until all drivers using that reset
line are unloaded.
So effectively this new phy_ops.reset callback will be a no-op.

I know his register is shared between two USB IPs,
but I have not observed any issues.

[...]

quoted

-       priv->reset = devm_reset_control_get_optional_shared(&pdev->dev, NULL);
+       priv->reset = devm_reset_control_get_optional_shared(&pdev->dev, "phy");

I think this breaks compatibility with existing .dtbs and our
dt-bindings (as we're not documenting a "reset-names" property).
What is the goal of this one?

OK, If we pass NULL over here there is the possibility
USB phy will not get registered.

Best regards,
Martin

Thanks

-Anand

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