Hi Thinh,
On Linux kernel v6.3
Test procedure:
- modprobe g_zero
- Connect to PC host
- systemctl suspend
A large delay of 3 seconds is observed. The delay comes from dwc3_gadget_suspend()->dwc3_gadget_run_stop() waiting for DWC3_DSTS_DEVCTRLHLT to be set.
It returns -ETIMEDOUT.
Are we missing something to do a clean stop during suspend?
FYI. Unloading g_zero does not show this delay on stop.
cheers,
-roger
Hi,
On Wed, Apr 26, 2023, Roger Quadros wrote:
> Hi Thinh,
>
> On Linux kernel v6.3
> Test procedure:
>
> - modprobe g_zero
> - Connect to PC host
> - systemctl suspend
>
> A large delay of 3 seconds is observed. The delay comes from dwc3_gadget_suspend()->dwc3_gadget_run_stop() waiting for DWC3_DSTS_DEVCTRLHLT to be set.
> It returns -ETIMEDOUT.
>
> Are we missing something to do a clean stop during suspend?
>
> FYI. Unloading g_zero does not show this delay on stop.
>
> cheers,
> -roger
When clearing run_stop bit and the controller doesn't halt, that usually
means there are active transfers/endpoints that aren't ended yet.
The dwc3_gadget_suspend() doesn't properly do all the cleanup before
clearing the run_stop bit. I think you just need to call
dwc3_gadget_soft_disconnect() in dwc3_gadget_suspend() to fix this.
Thanks,
Thinh
Hi,
On 26/04/2023 23:01, Thinh Nguyen wrote:
> Hi,
>
> On Wed, Apr 26, 2023, Roger Quadros wrote:
>> Hi Thinh,
>>
>> On Linux kernel v6.3
>> Test procedure:
>>
>> - modprobe g_zero
>> - Connect to PC host
>> - systemctl suspend
>>
>> A large delay of 3 seconds is observed. The delay comes from dwc3_gadget_suspend()->dwc3_gadget_run_stop() waiting for DWC3_DSTS_DEVCTRLHLT to be set.
>> It returns -ETIMEDOUT.
>>
>> Are we missing something to do a clean stop during suspend?
>>
>> FYI. Unloading g_zero does not show this delay on stop.
>>
>> cheers,
>> -roger
>
> When clearing run_stop bit and the controller doesn't halt, that usually
> means there are active transfers/endpoints that aren't ended yet.
>
> The dwc3_gadget_suspend() doesn't properly do all the cleanup before
> clearing the run_stop bit. I think you just need to call
> dwc3_gadget_soft_disconnect() in dwc3_gadget_suspend() to fix this.
That seems to do the trick.
How does this look?
-------------------------- drivers/usb/dwc3/gadget.c --------------------------
@@ -4674,11 +4676,18 @@ void dwc3_gadget_exit(struct dwc3 *dwc)
int dwc3_gadget_suspend(struct dwc3 *dwc)
{
unsigned long flags;
+ int ret;
- if (!dwc->gadget_driver)
+ if (!dwc->gadget_driver || !dwc->softconnect)
return 0;
- dwc3_gadget_run_stop(dwc, false, false);
+ ret = dwc3_gadget_soft_disconnect(dwc);
+ if (ret)
+ goto err0;
+
+ ret = dwc3_gadget_run_stop(dwc, false, false);
+ if (ret)
+ goto err1;
spin_lock_irqsave(&dwc->lock, flags);
dwc3_disconnect_gadget(dwc);
@@ -4686,6 +4695,22 @@ int dwc3_gadget_suspend(struct dwc3 *dwc)
spin_unlock_irqrestore(&dwc->lock, flags);
return 0;
+
+err1:
+ /*
+ * In the Synopsys DWC_usb31 1.90a programming guide section
+ * 4.1.9, it specifies that for a reconnect after a
+ * device-initiated disconnect requires a core soft reset
+ * (DCTL.CSftRst) before enabling the run/stop bit.
+ */
+ dwc3_core_soft_reset(dwc);
+ dwc3_event_buffers_setup(dwc);
+
+ ret = dwc3_gadget_run_stop(dwc, true, false);
+
+err0:
+ dev_info(dwc->dev, "%s error %d\n", __func__, ret);
+ return ret;
}
int dwc3_gadget_resume(struct dwc3 *dwc)
@@ -4695,6 +4720,15 @@ int dwc3_gadget_resume(struct dwc3 *dwc)
if (!dwc->gadget_driver || !dwc->softconnect)
return 0;
+ /*
+ * In the Synopsys DWC_usb31 1.90a programming guide section
+ * 4.1.9, it specifies that for a reconnect after a
+ * device-initiated disconnect requires a core soft reset
+ * (DCTL.CSftRst) before enabling the run/stop bit.
+ */
+ dwc3_core_soft_reset(dwc);
+ dwc3_event_buffers_setup(dwc);
+
ret = __dwc3_gadget_start(dwc);
if (ret < 0)
goto err0;
--
cheers,
-roger
On Thu, Apr 27, 2023, Roger Quadros wrote:
> Hi,
>
> On 26/04/2023 23:01, Thinh Nguyen wrote:
> > Hi,
> >
> > On Wed, Apr 26, 2023, Roger Quadros wrote:
> >> Hi Thinh,
> >>
> >> On Linux kernel v6.3
> >> Test procedure:
> >>
> >> - modprobe g_zero
> >> - Connect to PC host
> >> - systemctl suspend
> >>
> >> A large delay of 3 seconds is observed. The delay comes from dwc3_gadget_suspend()->dwc3_gadget_run_stop() waiting for DWC3_DSTS_DEVCTRLHLT to be set.
> >> It returns -ETIMEDOUT.
> >>
> >> Are we missing something to do a clean stop during suspend?
> >>
> >> FYI. Unloading g_zero does not show this delay on stop.
> >>
> >> cheers,
> >> -roger
> >
> > When clearing run_stop bit and the controller doesn't halt, that usually
> > means there are active transfers/endpoints that aren't ended yet.
> >
> > The dwc3_gadget_suspend() doesn't properly do all the cleanup before
> > clearing the run_stop bit. I think you just need to call
> > dwc3_gadget_soft_disconnect() in dwc3_gadget_suspend() to fix this.
>
> That seems to do the trick.
> How does this look?
>
> -------------------------- drivers/usb/dwc3/gadget.c --------------------------
> @@ -4674,11 +4676,18 @@ void dwc3_gadget_exit(struct dwc3 *dwc)
> int dwc3_gadget_suspend(struct dwc3 *dwc)
> {
> unsigned long flags;
> + int ret;
>
> - if (!dwc->gadget_driver)
> + if (!dwc->gadget_driver || !dwc->softconnect)
> return 0;
>
> - dwc3_gadget_run_stop(dwc, false, false);
> + ret = dwc3_gadget_soft_disconnect(dwc);
> + if (ret)
> + goto err0;
> +
> + ret = dwc3_gadget_run_stop(dwc, false, false);
> + if (ret)
> + goto err1;
>
We already clear run_stop in dwc3_gadget_soft_disconnect().
Can you try the following change (not tested):
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index c0ca4d12f95d..2996bcb4d53d 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -2699,6 +2699,21 @@ static int dwc3_gadget_soft_disconnect(struct dwc3 *dwc)
return ret;
}
+static int dwc3_gadget_soft_connect(struct dwc3 *dwc)
+{
+ /*
+ * In the Synopsys DWC_usb31 1.90a programming guide section
+ * 4.1.9, it specifies that for a reconnect after a
+ * device-initiated disconnect requires a core soft reset
+ * (DCTL.CSftRst) before enabling the run/stop bit.
+ */
+ dwc3_core_soft_reset(dwc);
+
+ dwc3_event_buffers_setup(dwc);
+ __dwc3_gadget_start(dwc);
+ return dwc3_gadget_run_stop(dwc, true);
+}
+
static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on)
{
struct dwc3 *dwc = gadget_to_dwc(g);
@@ -2737,21 +2752,10 @@ static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on)
synchronize_irq(dwc->irq_gadget);
- if (!is_on) {
+ if (!is_on)
ret = dwc3_gadget_soft_disconnect(dwc);
- } else {
- /*
- * In the Synopsys DWC_usb31 1.90a programming guide section
- * 4.1.9, it specifies that for a reconnect after a
- * device-initiated disconnect requires a core soft reset
- * (DCTL.CSftRst) before enabling the run/stop bit.
- */
- dwc3_core_soft_reset(dwc);
-
- dwc3_event_buffers_setup(dwc);
- __dwc3_gadget_start(dwc);
- ret = dwc3_gadget_run_stop(dwc, true);
- }
+ else
+ ret = dwc3_gadget_soft_connect(dwc);
pm_runtime_put(dwc->dev);
@@ -4655,42 +4659,39 @@ void dwc3_gadget_exit(struct dwc3 *dwc)
int dwc3_gadget_suspend(struct dwc3 *dwc)
{
unsigned long flags;
+ int ret;
if (!dwc->gadget_driver)
return 0;
- dwc3_gadget_run_stop(dwc, false);
+ ret = dwc3_gadget_soft_disconnect(dwc);
+ if (ret)
+ goto err;
spin_lock_irqsave(&dwc->lock, flags);
dwc3_disconnect_gadget(dwc);
- __dwc3_gadget_stop(dwc);
spin_unlock_irqrestore(&dwc->lock, flags);
return 0;
+
+err:
+ /*
+ * Attempt to reset the controller's state. Likely no
+ * communication can be established until the host
+ * performs a port reset.
+ */
+ if (dwc->softconnect)
+ dwc3_gadget_soft_connect(dwc);
+
+ return ret;
}
int dwc3_gadget_resume(struct dwc3 *dwc)
{
- int ret;
-
if (!dwc->gadget_driver || !dwc->softconnect)
return 0;
- ret = __dwc3_gadget_start(dwc);
- if (ret < 0)
- goto err0;
-
- ret = dwc3_gadget_run_stop(dwc, true);
- if (ret < 0)
- goto err1;
-
- return 0;
-
-err1:
- __dwc3_gadget_stop(dwc);
-
-err0:
- return ret;
+ return dwc3_gadget_soft_connect(dwc);
}
void dwc3_gadget_process_pending_events(struct dwc3 *dwc)
--
Thanks,
Thinh
On 28/04/2023 01:13, Thinh Nguyen wrote:
> On Thu, Apr 27, 2023, Roger Quadros wrote:
>> Hi,
>>
>> On 26/04/2023 23:01, Thinh Nguyen wrote:
>>> Hi,
>>>
>>> On Wed, Apr 26, 2023, Roger Quadros wrote:
>>>> Hi Thinh,
>>>>
>>>> On Linux kernel v6.3
>>>> Test procedure:
>>>>
>>>> - modprobe g_zero
>>>> - Connect to PC host
>>>> - systemctl suspend
>>>>
>>>> A large delay of 3 seconds is observed. The delay comes from dwc3_gadget_suspend()->dwc3_gadget_run_stop() waiting for DWC3_DSTS_DEVCTRLHLT to be set.
>>>> It returns -ETIMEDOUT.
>>>>
>>>> Are we missing something to do a clean stop during suspend?
>>>>
>>>> FYI. Unloading g_zero does not show this delay on stop.
>>>>
>>>> cheers,
>>>> -roger
>>>
>>> When clearing run_stop bit and the controller doesn't halt, that usually
>>> means there are active transfers/endpoints that aren't ended yet.
>>>
>>> The dwc3_gadget_suspend() doesn't properly do all the cleanup before
>>> clearing the run_stop bit. I think you just need to call
>>> dwc3_gadget_soft_disconnect() in dwc3_gadget_suspend() to fix this.
>>
>> That seems to do the trick.
>> How does this look?
>>
>> -------------------------- drivers/usb/dwc3/gadget.c --------------------------
>> @@ -4674,11 +4676,18 @@ void dwc3_gadget_exit(struct dwc3 *dwc)
>> int dwc3_gadget_suspend(struct dwc3 *dwc)
>> {
>> unsigned long flags;
>> + int ret;
>>
>> - if (!dwc->gadget_driver)
>> + if (!dwc->gadget_driver || !dwc->softconnect)
>> return 0;
>>
>> - dwc3_gadget_run_stop(dwc, false, false);
>> + ret = dwc3_gadget_soft_disconnect(dwc);
>> + if (ret)
>> + goto err0;
>> +
>> + ret = dwc3_gadget_run_stop(dwc, false, false);
>> + if (ret)
>> + goto err1;
>>
>
> We already clear run_stop in dwc3_gadget_soft_disconnect().
>
> Can you try the following change (not tested):
>
> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
> index c0ca4d12f95d..2996bcb4d53d 100644
> --- a/drivers/usb/dwc3/gadget.c
> +++ b/drivers/usb/dwc3/gadget.c
> @@ -2699,6 +2699,21 @@ static int dwc3_gadget_soft_disconnect(struct dwc3 *dwc)
> return ret;
> }
>
> +static int dwc3_gadget_soft_connect(struct dwc3 *dwc)
> +{
> + /*
> + * In the Synopsys DWC_usb31 1.90a programming guide section
> + * 4.1.9, it specifies that for a reconnect after a
> + * device-initiated disconnect requires a core soft reset
> + * (DCTL.CSftRst) before enabling the run/stop bit.
> + */
> + dwc3_core_soft_reset(dwc);
> +
> + dwc3_event_buffers_setup(dwc);
> + __dwc3_gadget_start(dwc);
> + return dwc3_gadget_run_stop(dwc, true);
return dwc3_gadget_run_stop(dwc, true, false);
> +}> +
> static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on)
> {
> struct dwc3 *dwc = gadget_to_dwc(g);
> @@ -2737,21 +2752,10 @@ static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on)
>
> synchronize_irq(dwc->irq_gadget);
>
> - if (!is_on) {
> + if (!is_on)
> ret = dwc3_gadget_soft_disconnect(dwc);
> - } else {
> - /*
> - * In the Synopsys DWC_usb31 1.90a programming guide section
> - * 4.1.9, it specifies that for a reconnect after a
> - * device-initiated disconnect requires a core soft reset
> - * (DCTL.CSftRst) before enabling the run/stop bit.
> - */
> - dwc3_core_soft_reset(dwc);
> -
> - dwc3_event_buffers_setup(dwc);
> - __dwc3_gadget_start(dwc);
> - ret = dwc3_gadget_run_stop(dwc, true);
> - }
> + else
> + ret = dwc3_gadget_soft_connect(dwc);
>
> pm_runtime_put(dwc->dev);
>
> @@ -4655,42 +4659,39 @@ void dwc3_gadget_exit(struct dwc3 *dwc)
> int dwc3_gadget_suspend(struct dwc3 *dwc)
> {
> unsigned long flags;
> + int ret;
>
> if (!dwc->gadget_driver)
We need to check for dwc->softconnect here. If it is not set that means
controller has already stopped so we can simply exit.
> return 0;
>
> - dwc3_gadget_run_stop(dwc, false);
> + ret = dwc3_gadget_soft_disconnect(dwc);
> + if (ret)
> + goto err;
>
> spin_lock_irqsave(&dwc->lock, flags);
> dwc3_disconnect_gadget(dwc);
> - __dwc3_gadget_stop(dwc);
> spin_unlock_irqrestore(&dwc->lock, flags);
>
> return 0;
> +
> +err:
> + /*
> + * Attempt to reset the controller's state. Likely no
> + * communication can be established until the host
> + * performs a port reset.
> + */
> + if (dwc->softconnect)
> + dwc3_gadget_soft_connect(dwc);
> +
> + return ret;
> }
>
> int dwc3_gadget_resume(struct dwc3 *dwc)
> {
> - int ret;
> -
> if (!dwc->gadget_driver || !dwc->softconnect)
> return 0;
>
> - ret = __dwc3_gadget_start(dwc);
> - if (ret < 0)
> - goto err0;
> -
> - ret = dwc3_gadget_run_stop(dwc, true);
> - if (ret < 0)
> - goto err1;
> -
> - return 0;
> -
> -err1:
> - __dwc3_gadget_stop(dwc);
> -
> -err0:
> - return ret;
> + return dwc3_gadget_soft_connect(dwc);
> }
>
> void dwc3_gadget_process_pending_events(struct dwc3 *dwc)
Everything else looks ok. I will send a patch soon.
--
cheers,
-roger
On Fri, Apr 28, 2023, Roger Quadros wrote:
>
>
> On 28/04/2023 01:13, Thinh Nguyen wrote:
> > On Thu, Apr 27, 2023, Roger Quadros wrote:
> >> Hi,
> >>
> >> On 26/04/2023 23:01, Thinh Nguyen wrote:
> >>> Hi,
> >>>
> >>> On Wed, Apr 26, 2023, Roger Quadros wrote:
> >>>> Hi Thinh,
> >>>>
> >>>> On Linux kernel v6.3
> >>>> Test procedure:
> >>>>
> >>>> - modprobe g_zero
> >>>> - Connect to PC host
> >>>> - systemctl suspend
> >>>>
> >>>> A large delay of 3 seconds is observed. The delay comes from dwc3_gadget_suspend()->dwc3_gadget_run_stop() waiting for DWC3_DSTS_DEVCTRLHLT to be set.
> >>>> It returns -ETIMEDOUT.
> >>>>
> >>>> Are we missing something to do a clean stop during suspend?
> >>>>
> >>>> FYI. Unloading g_zero does not show this delay on stop.
> >>>>
> >>>> cheers,
> >>>> -roger
> >>>
> >>> When clearing run_stop bit and the controller doesn't halt, that usually
> >>> means there are active transfers/endpoints that aren't ended yet.
> >>>
> >>> The dwc3_gadget_suspend() doesn't properly do all the cleanup before
> >>> clearing the run_stop bit. I think you just need to call
> >>> dwc3_gadget_soft_disconnect() in dwc3_gadget_suspend() to fix this.
> >>
> >> That seems to do the trick.
> >> How does this look?
> >>
> >> -------------------------- drivers/usb/dwc3/gadget.c --------------------------
> >> @@ -4674,11 +4676,18 @@ void dwc3_gadget_exit(struct dwc3 *dwc)
> >> int dwc3_gadget_suspend(struct dwc3 *dwc)
> >> {
> >> unsigned long flags;
> >> + int ret;
> >>
> >> - if (!dwc->gadget_driver)
> >> + if (!dwc->gadget_driver || !dwc->softconnect)
> >> return 0;
> >>
> >> - dwc3_gadget_run_stop(dwc, false, false);
> >> + ret = dwc3_gadget_soft_disconnect(dwc);
> >> + if (ret)
> >> + goto err0;
> >> +
> >> + ret = dwc3_gadget_run_stop(dwc, false, false);
> >> + if (ret)
> >> + goto err1;
> >>
> >
> > We already clear run_stop in dwc3_gadget_soft_disconnect().
> >
> > Can you try the following change (not tested):
> >
> > diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
> > index c0ca4d12f95d..2996bcb4d53d 100644
> > --- a/drivers/usb/dwc3/gadget.c
> > +++ b/drivers/usb/dwc3/gadget.c
> > @@ -2699,6 +2699,21 @@ static int dwc3_gadget_soft_disconnect(struct dwc3 *dwc)
> > return ret;
> > }
> >
> > +static int dwc3_gadget_soft_connect(struct dwc3 *dwc)
> > +{
> > + /*
> > + * In the Synopsys DWC_usb31 1.90a programming guide section
> > + * 4.1.9, it specifies that for a reconnect after a
> > + * device-initiated disconnect requires a core soft reset
> > + * (DCTL.CSftRst) before enabling the run/stop bit.
> > + */
> > + dwc3_core_soft_reset(dwc);
> > +
> > + dwc3_event_buffers_setup(dwc);
> > + __dwc3_gadget_start(dwc);
> > + return dwc3_gadget_run_stop(dwc, true);
>
> return dwc3_gadget_run_stop(dwc, true, false);
You need to rebase your change to Greg's usb-next.
>
> > +}> +
> > static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on)
> > {
> > struct dwc3 *dwc = gadget_to_dwc(g);
> > @@ -2737,21 +2752,10 @@ static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on)
> >
> > synchronize_irq(dwc->irq_gadget);
> >
> > - if (!is_on) {
> > + if (!is_on)
> > ret = dwc3_gadget_soft_disconnect(dwc);
> > - } else {
> > - /*
> > - * In the Synopsys DWC_usb31 1.90a programming guide section
> > - * 4.1.9, it specifies that for a reconnect after a
> > - * device-initiated disconnect requires a core soft reset
> > - * (DCTL.CSftRst) before enabling the run/stop bit.
> > - */
> > - dwc3_core_soft_reset(dwc);
> > -
> > - dwc3_event_buffers_setup(dwc);
> > - __dwc3_gadget_start(dwc);
> > - ret = dwc3_gadget_run_stop(dwc, true);
> > - }
> > + else
> > + ret = dwc3_gadget_soft_connect(dwc);
> >
> > pm_runtime_put(dwc->dev);
> >
> > @@ -4655,42 +4659,39 @@ void dwc3_gadget_exit(struct dwc3 *dwc)
> > int dwc3_gadget_suspend(struct dwc3 *dwc)
> > {
> > unsigned long flags;
> > + int ret;
> >
> > if (!dwc->gadget_driver)
>
> We need to check for dwc->softconnect here. If it is not set that means
> controller has already stopped so we can simply exit.
That makes sense. Perhaps that can be a separate change?
>
> > return 0;
> >
> > - dwc3_gadget_run_stop(dwc, false);
> > + ret = dwc3_gadget_soft_disconnect(dwc);
> > + if (ret)
> > + goto err;
> >
> > spin_lock_irqsave(&dwc->lock, flags);
> > dwc3_disconnect_gadget(dwc);
> > - __dwc3_gadget_stop(dwc);
> > spin_unlock_irqrestore(&dwc->lock, flags);
> >
> > return 0;
> > +
> > +err:
> > + /*
> > + * Attempt to reset the controller's state. Likely no
> > + * communication can be established until the host
> > + * performs a port reset.
> > + */
> > + if (dwc->softconnect)
If we check dwc->softconnect at start, we can skip the check here.
> > + dwc3_gadget_soft_connect(dwc);
> > +
> > + return ret;
> > }
> >
> > int dwc3_gadget_resume(struct dwc3 *dwc)
> > {
> > - int ret;
> > -
> > if (!dwc->gadget_driver || !dwc->softconnect)
> > return 0;
> >
> > - ret = __dwc3_gadget_start(dwc);
> > - if (ret < 0)
> > - goto err0;
> > -
> > - ret = dwc3_gadget_run_stop(dwc, true);
> > - if (ret < 0)
> > - goto err1;
> > -
> > - return 0;
> > -
> > -err1:
> > - __dwc3_gadget_stop(dwc);
> > -
> > -err0:
> > - return ret;
> > + return dwc3_gadget_soft_connect(dwc);
> > }
> >
> > void dwc3_gadget_process_pending_events(struct dwc3 *dwc)
>
> Everything else looks ok. I will send a patch soon.
>
Thanks,
Thinh