On 10/20/2016 11:38 AM, Randy Li wrote:
> On the rk3288 USB host-only port (the one that's not the OTG-enabled
> port) the PHY can get into a bad state when a wakeup is asserted (not
> just a wakeup from full system suspend but also a wakeup from
> autosuspend).
>
> We can get the PHY out of its bad state by asserting its "port reset",
> but unfortunately that seems to assert a reset onto the USB bus so it
> could confuse things if we don't actually deenumerate / reenumerate the
> device.
>
> We can also get the PHY out of its bad state by fully resetting it using
> the reset from the CRU (clock reset unit) in chip, which does a more full
> reset. The CRU-based reset appears to actually cause devices on the bus
> to be removed and reinserted, which fixes the problem (albeit in a hacky
> way).
>
> It's unfortunate that we need to do a full re-enumeration of devices at
> wakeup time, but this is better than alternative of letting the bus get
> wedged.
>
> Signed-off-by: Randy Li <ayaka@xxxxxxxxxxx>
> ---
> drivers/usb/dwc2/core.h | 1 +
> drivers/usb/dwc2/core_intr.c | 11 +++++++++++
> drivers/usb/dwc2/platform.c | 9 +++++++++
> 3 files changed, 21 insertions(+)
>
> diff --git a/drivers/usb/dwc2/core.h b/drivers/usb/dwc2/core.h
> index 2a21a04..e91ddbc 100644
> --- a/drivers/usb/dwc2/core.h
> +++ b/drivers/usb/dwc2/core.h
> @@ -859,6 +859,7 @@ struct dwc2_hsotg {
> unsigned int ll_hw_enabled:1;
>
> struct phy *phy;
> + struct work_struct phy_rst_work;
> struct usb_phy *uphy;
> struct dwc2_hsotg_plat *plat;
> struct regulator_bulk_data supplies[ARRAY_SIZE(dwc2_hsotg_supply_names)];
> diff --git a/drivers/usb/dwc2/core_intr.c b/drivers/usb/dwc2/core_intr.c
> index d85c5c9..c3d2168 100644
> --- a/drivers/usb/dwc2/core_intr.c
> +++ b/drivers/usb/dwc2/core_intr.c
> @@ -345,6 +345,7 @@ static void dwc2_handle_session_req_intr(struct dwc2_hsotg *hsotg)
> static void dwc2_handle_wakeup_detected_intr(struct dwc2_hsotg *hsotg)
> {
> int ret;
> + struct device_node *np = hsotg->dev->of_node;
>
> /* Clear interrupt */
> dwc2_writel(GINTSTS_WKUPINT, hsotg->regs + GINTSTS);
> @@ -379,6 +380,16 @@ static void dwc2_handle_wakeup_detected_intr(struct dwc2_hsotg *hsotg)
> /* Restart the Phy Clock */
> pcgcctl &= ~PCGCTL_STOPPCLK;
> dwc2_writel(pcgcctl, hsotg->regs + PCGCTL);
> +
> + /*
> + * It is a quirk in Rockchip RK3288, causing by
> + * a hardware bug. This will propagate out and
> + * eventually we'll re-enumerate the device.
> + * Not great but the best we can do
> + */
> + if (of_device_is_compatible(np, "rockchip,rk3288-usb"))
> + schedule_work(&hsotg->phy_rst_work);
> +
> mod_timer(&hsotg->wkp_timer,
> jiffies + msecs_to_jiffies(71));
> } else {
> diff --git a/drivers/usb/dwc2/platform.c b/drivers/usb/dwc2/platform.c
> index 8e1728b..65953cf 100644
> --- a/drivers/usb/dwc2/platform.c
> +++ b/drivers/usb/dwc2/platform.c
> @@ -366,6 +366,14 @@ int dwc2_lowlevel_hw_disable(struct dwc2_hsotg *hsotg)
> return ret;
> }
>
> +/* Only used to reset usb phy at interrupter runtime */
> +static void dwc2_reset_phy_work(struct work_struct *data)
> +{
> + struct dwc2_hsotg *hsotg = container_of(data, struct dwc2_hsotg,
> + phy_rst_work);
> + phy_reset(hsotg->phy);
> +}
> +
> static int dwc2_lowlevel_hw_init(struct dwc2_hsotg *hsotg)
> {
> int i, ret;
> @@ -410,6 +418,7 @@ static int dwc2_lowlevel_hw_init(struct dwc2_hsotg *hsotg)
> return ret;
> }
> }
> + INIT_WORK(&hsotg->phy_rst_work, dwc2_reset_phy_work);
>
> if (!hsotg->phy) {
> hsotg->uphy = devm_usb_get_phy(hsotg->dev, USB_PHY_TYPE_USB2);
>
Hi Randy,
This fails compile if CONFIG_GENERIC_PHY is disabled. I think you need
to make a fix to your phy_reset patch first.
Regards,
John
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