On Thu, Dec 6, 2018 at 8:49 PM Stephan Gerhold <stephan@xxxxxxxxxxx> wrote:
>
> Commit 211f658b7b40 ("usb: dwc3: pci: Use devm functions to get
> the phy GPIOs") changed the code to claim the PHY GPIOs permanently
> for Intel Baytrail devices.
>
> This causes issues when the actual PHY driver attempts to claim the
> same GPIO descriptors. For example, tusb1210 now fails to probe with:
>
> tusb1210: probe of dwc3.0.auto.ulpi failed with error -16 (EBUSY)
>
> dwc3-pci needs to turn on the PHY once before dwc3 is loaded, but
> usually the PHY driver will then hold the GPIOs to turn off the
> PHY when requested (e.g. during suspend).
>
> To fix the problem, this reverts the commit to restore the old
> behavior to put the GPIOs immediately after usage.
>
> Link: https://www.spinics.net/lists/linux-usb/msg174681.html
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Stephan Gerhold <stephan@xxxxxxxxxxx>
> ---
> drivers/usb/dwc3/dwc3-pci.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/usb/dwc3/dwc3-pci.c b/drivers/usb/dwc3/dwc3-pci.c
> index 842795856bf4..fdc6e4e403e8 100644
> --- a/drivers/usb/dwc3/dwc3-pci.c
> +++ b/drivers/usb/dwc3/dwc3-pci.c
> @@ -170,20 +170,20 @@ static int dwc3_pci_quirks(struct dwc3_pci *dwc)
> * put the gpio descriptors again here because the phy driver
> * might want to grab them, too.
> */
> - gpio = devm_gpiod_get_optional(&pdev->dev, "cs",
> - GPIOD_OUT_LOW);
> + gpio = gpiod_get_optional(&pdev->dev, "cs", GPIOD_OUT_LOW);
> if (IS_ERR(gpio))
> return PTR_ERR(gpio);
>
> gpiod_set_value_cansleep(gpio, 1);
> + gpiod_put(gpio);
>
> - gpio = devm_gpiod_get_optional(&pdev->dev, "reset",
> - GPIOD_OUT_LOW);
> + gpio = gpiod_get_optional(&pdev->dev, "reset", GPIOD_OUT_LOW);
> if (IS_ERR(gpio))
> return PTR_ERR(gpio);
>
> if (gpio) {
> gpiod_set_value_cansleep(gpio, 1);
> + gpiod_put(gpio);
> usleep_range(10000, 11000);
If something happens to GPIO line in between of these lines, the sleep
might become obsolete. Shouldn't gpiod_put() be placed after?
> }
> }
--
With Best Regards,
Andy Shevchenko
