Re: [PATCH] phy: tegra: xusb: Default otg mode to peripheral

[Jon Hunter <jonathanh@nvidia.com>]

On 05/05/2025 08:44, Aaron Kling wrote:
> On Sun, Apr 20, 2025 at 8:44 PM Aaron Kling <webgeek1234@gmail.com> wrote:
>>
>> On Sun, Apr 13, 2025 at 11:45 PM Aaron Kling <webgeek1234@gmail.com> wrote:
>>>
>>> On Fri, Apr 4, 2025 at 3:18 AM Aaron Kling via B4 Relay
>>> <devnull+webgeek1234.gmail.com@kernel.org> wrote:
>>>>
>>>> From: Aaron Kling <webgeek1234@gmail.com>
>>>>
>>>> Currently, if usb-role-switch is set and role-switch-default-mode is
>>>> not, a xusb port will be inoperable until that port is hotplugged,
>>>> because the driver defaults to role none. Instead of requiring all
>>>> devices to set the default mode, assume that the port is primarily
>>>> intended for use in device mode. This assumption already has precedence
>>>> in the synopsys dwc3 driver.
>>>>
>>>> Signed-off-by: Aaron Kling <webgeek1234@gmail.com>
>>>> ---
>>>>   drivers/phy/tegra/xusb.c | 8 +++-----
>>>>   1 file changed, 3 insertions(+), 5 deletions(-)
>>>>
>>>> diff --git a/drivers/phy/tegra/xusb.c b/drivers/phy/tegra/xusb.c
>>>> index 79d4814d758d5e1f0e8200d61e131606adbb0e2d..c56e83216d0f566a09b67377172fb04c8406f4cf 100644
>>>> --- a/drivers/phy/tegra/xusb.c
>>>> +++ b/drivers/phy/tegra/xusb.c
>>>> @@ -731,13 +731,11 @@ static void tegra_xusb_parse_usb_role_default_mode(struct tegra_xusb_port *port)
>>>>
>>>>          if (mode == USB_DR_MODE_HOST)
>>>>                  role = USB_ROLE_HOST;
>>>> -       else if (mode == USB_DR_MODE_PERIPHERAL)
>>>> +       else
>>>>                  role = USB_ROLE_DEVICE;
>>>>
>>>> -       if (role != USB_ROLE_NONE) {
>>>> -               usb_role_switch_set_role(port->usb_role_sw, role);
>>>> -               dev_dbg(&port->dev, "usb role default mode is %s", modes[mode]);
>>>> -       }
>>>> +       usb_role_switch_set_role(port->usb_role_sw, role);
>>>> +       dev_dbg(&port->dev, "usb role default mode is %s", modes[mode]);
>>>>   }
>>>>
>>>>   static int tegra_xusb_usb2_port_parse_dt(struct tegra_xusb_usb2_port *usb2)
>>>>
>>>> ---
>>>> base-commit: 91e5bfe317d8f8471fbaa3e70cf66cae1314a516
>>>> change-id: 20250404-xusb-peripheral-c45b1637f33b
>>>>
>>>> Best regards,
>>>> --
>>>> Aaron Kling <webgeek1234@gmail.com>
>>>>
>>>>
>>>
>>> Friendly reminder about this patch.
>>>
>>> Sincerely,
>>> Aaron
>>
>> Friendly re-reminder about this series.
>>
>> Sincerely,
>> Aaron Kling
> 
> It has been over a month since this patch was submitted. And neither
> this nor any other patch I've submitted since have been reviewed or
> responded to by any Tegra subsystem maintainer. Is there anyone else
> that can review these and pick them up? Or is there any other path
> forward for series that get ignored by the subsystem maintainers?


Sorry for the delay. I have had a look at this patch and I am not sure 
about this. The function you are changing is called 
'tegra_xusb_parse_usb_role_default_mode' and it is doing precisely what 
it was intended to do. In other words, parse device-tree and set the 
mode accordingly. So forcing the mode in this function does not feel 
correct.

Also from the description it is not 100% clear to me the exact scenario 
where this is really a problem.

Jon

-- 
nvpublic