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

From: John Youn
Date: Tue Dec 06 2016 - 14:43:56 EST


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@xxxxxxxxxxxx>

Regards,
John


> åæç iPad åé
>
>> John Youn <John.Youn@xxxxxxxxxxxx> æ 2016å10æ25æ äå9:30 åéï
>>
>>> 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@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.
>>> 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
>
>