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

From: Ayaka
Date: Tue Dec 06 2016 - 07:00:48 EST


Hello John
I still waiting them be merged, but I still can't find it at next-20161206.

從我的 iPad 傳送

> John Youn <John.Youn@xxxxxxxxxxxx> 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@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