[U-Boot] [PATCH] usb: ehci: Fix test mode for connected ports

[Simon Glass]

Hi,

On Tue, Sep 17, 2013 at 6:29 PM, Julius Werner <jwerner at chromium.org> wrote:

> The EHCI controller has some very specific requirements for the USB 2.0
> port test modes, which were not closely followed in the initial test
> mode commit. It demands that the host controller is completely shut down
> (all ports suspended, Run/Stop bit unset) when activating test mode, and
> will not work on an already enumerated port.
>
> This patch fixes that by introducing a new ehci_shutdown() function that
> closely follows the procedure listed in EHCI 4.14. Also, when we have
> such a function anyway, we might as well also use it in
> usb_lowlevel_stop() to make the normal host controller shutdown cleaner.
>

Marek this seems like a bug fix - should we pick it up for the release?


>
> Signed-off-by: Julius Werner <jwerner at chromium.org>
> ---
>  drivers/usb/host/ehci-hcd.c | 31 +++++++++++++++++++++++++++++++
>  1 file changed, 31 insertions(+)
>
> diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c
> index fdad739..3143021 100644
> --- a/drivers/usb/host/ehci-hcd.c
> +++ b/drivers/usb/host/ehci-hcd.c
> @@ -190,6 +190,35 @@ out:
>         return ret;
>  }
>
> +static int ehci_shutdown(struct ehci_ctrl *ctrl)
>

Suggest a comment as to what this function does (e.g. a few lines from your
commit message).


> +{
> +       int i, ret = 0;
>

nit: = 0 not needed I think


> +       uint32_t cmd, reg;
> +
> +       cmd = ehci_readl(&ctrl->hcor->or_usbcmd);
> +       cmd &= ~(CMD_PSE | CMD_ASE);
> +       ehci_writel(&ctrl->hcor->or_usbcmd, cmd);
> +       ret = handshake(&ctrl->hcor->or_usbsts, STS_ASS | STS_PSS, 0, 8 *
> 1000);
> +
> +       if (!ret) {
> +               for (i = 0; i < CONFIG_SYS_USB_EHCI_MAX_ROOT_PORTS; i++) {
> +                       reg = ehci_readl(&ctrl->hcor->or_portsc[i]);
> +                       reg |= EHCI_PS_SUSP;
> +                       ehci_writel(&ctrl->hcor->or_portsc[i], reg);
> +               }
> +
> +               cmd &= ~CMD_RUN;
> +               ehci_writel(&ctrl->hcor->or_usbcmd, cmd);
> +               ret = handshake(&ctrl->hcor->or_usbsts, STS_HALT, STS_HALT,
> +                       8 * 1000);
> +       }
> +
> +       if (ret)
> +               printf("EHCI failed to shut down host controller.\n");
> +
> +       return ret;
> +}
> +
>  static int ehci_td_buffer(struct qTD *td, void *buf, size_t sz)
>  {
>         uint32_t delta, next;
> @@ -808,6 +837,7 @@ ehci_submit_root(struct usb_device *dev, unsigned long
> pipe, void *buffer,
>                         }
>                         break;
>                 case USB_PORT_FEAT_TEST:
> +                       ehci_shutdown(ctrl);
>

If it cannot be shut down, I suppose there is nothing that can be done
here. Should this function exit here, or not?


>                         reg &= ~(0xf << 16);
>                         reg |= ((le16_to_cpu(req->index) >> 8) & 0xf) <<
> 16;
>                         ehci_writel(status_reg, reg);
> @@ -878,6 +908,7 @@ unknown:
>
>  int usb_lowlevel_stop(int index)
>  {
> +       ehci_shutdown(&ehcic[index]);
>         return ehci_hcd_stop(index);
>  }
>
> --
> 1.7.12.4
>
>
Regards,
Simon