Re: [PATCH v9 1/2] usb: dwc2: assert phy reset when waking up in rk3288 platform

[John Youn <John.Youn@synopsys.com>]

On 12/6/2016 4:00 AM, Ayaka wrote:
> Hello John
>   I still waiting them be merged, but I still can't find it at next-20161206.
> 

Can you resubmit this fixing the checkpatch issues?

You can add my ack:

Acked-by: John Youn <johnyoun@synopsys.com>

Regards,
John


> 從我的 iPad 傳送
> 
>> John Youn <John.Youn@synopsys.com> 於 2016年10月25日 上午9:30 寫道：
>>
>>> On 10/23/2016 2:33 AM, ayaka wrote:
>>>
>>>
>>>> On 10/22/2016 03:27 AM, John Youn wrote:
>>>>> 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@soulik.info>
>>>>> ---
>>>>>  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.
>>> In the last time, cac18ecb6f44b11bc303d7afbae3887b27938fa4 have not been 
>>> merged, I though the
>>> [PATCH v8 1/3] phy: Add reset callback for not generic phy have been 
>>> merged before that. when the rebase abandon it.
>>> Should re-send that patch? As the mainline have not been affected, could 
>>> you arrange a squash for it?
>>
>> Hi Randy,
>>
>> Can you resend the fix to Kishon?
>>
>> The phy_reset patch landed in 4.9-rc so I think he should take the fix
>> for the next -rc. After that we can send the dwc2 change through
>> Felipe.
>>
>> Regards,
>> John
> 
>