diff mbox series

[v6] usb: dwc3: fix gadget mode suspend interrupt handler issue

Message ID 20230505014902.27313-1-quic_linyyuan@quicinc.com
State New
Headers show
Series [v6] usb: dwc3: fix gadget mode suspend interrupt handler issue | expand

Commit Message

Linyu Yuan May 5, 2023, 1:49 a.m. UTC
When work in gadget mode, currently driver doesn't update software level
link_state correctly as link state change event is not enabled for most
devices, in function dwc3_gadget_suspend_interrupt(), it will only pass
suspend event to UDC core when software level link state changes, so when
interrupt generated in sequences of suspend -> reset -> conndone ->
suspend, link state is not updated during reset and conndone, so second
suspend interrupt event will not pass to UDC core.

Remove link_state compare in dwc3_gadget_suspend_interrupt() and add a
suspended flag to replace the compare function.

Signed-off-by: Linyu Yuan <quic_linyyuan@quicinc.com>
---
v6: (refer v5 https://lore.kernel.org/linux-usb/1682476780-2367-1-git-send-email-quic_linyyuan@quicinc.com/)
1) change subject
2) only keep suspended flag related change

v5: (refer v4 https://lore.kernel.org/linux-usb/1682393256-15572-1-git-send-email-quic_linyyuan@quicinc.com/)
1) rename suspend_irq_happen to suspended and document it
2) add old_link_state for link change interrupt usage and change accordingly

v4: (refer v3 https://lore.kernel.org/linux-usb/1682053861-21737-1-git-send-email-quic_linyyuan@quicinc.com/)
1) remove link state checking in dwc3_gadget_wakeup_interrupt()
2) remove two switch/case to if opeartion

v3: (refer v2 https://lore.kernel.org/linux-usb/1682042472-21222-1-git-send-email-quic_linyyuan@quicinc.com/)
no code change since v2, changes compare v1 as below,
1) add a flag suspend_irq_happen to simplify dwc3_gadget_suspend_interrupt(),
   it will avoid refer to software level link_state, finally link_state will
   only used in dwc3_gadget_linksts_change_interrupt().
2) remove sw setting of link_state in dwc3_gadget_func_wakeup()
3) add dwc3_gadget_interrupt_early() to correct setting of link_state
   and suspend_irq_happen.

v2: update according v1 discussion
v1: https://lore.kernel.org/linux-usb/1675221286-23833-1-git-send-email-quic_linyyuan@quicinc.com/

 drivers/usb/dwc3/core.h   | 2 ++
 drivers/usb/dwc3/gadget.c | 7 ++++++-
 2 files changed, 8 insertions(+), 1 deletion(-)

Comments

Thinh Nguyen May 8, 2023, 10:13 p.m. UTC | #1
On Mon, May 08, 2023, Linyu Yuan wrote:
> 
> On 5/6/2023 8:32 AM, Thinh Nguyen wrote:
> > On Fri, May 05, 2023, Linyu Yuan wrote:
> > > When work in gadget mode, currently driver doesn't update software level
> > > link_state correctly as link state change event is not enabled for most
> > > devices, in function dwc3_gadget_suspend_interrupt(), it will only pass
> > > suspend event to UDC core when software level link state changes, so when
> > > interrupt generated in sequences of suspend -> reset -> conndone ->
> > > suspend, link state is not updated during reset and conndone, so second
> > > suspend interrupt event will not pass to UDC core.
> > > 
> > > Remove link_state compare in dwc3_gadget_suspend_interrupt() and add a
> > > suspended flag to replace the compare function.
> > > 
> > > Signed-off-by: Linyu Yuan <quic_linyyuan@quicinc.com>
> > > ---
> > > v6: (refer v5 https://urldefense.com/v3/__https://lore.kernel.org/linux-usb/1682476780-2367-1-git-send-email-quic_linyyuan@quicinc.com/__;!!A4F2R9G_pg!dIQ2VHccmZTXp1-59hTFfEhc65W0gatf1n2wmBfs5Yb0ipjHksD_ESQSmgXky1o1sc4wEZ5qp9JKV7IKmk5Km4bJzi2pGg$ )
> > > 1) change subject
> > > 2) only keep suspended flag related change
> > > 
> > > v5: (refer v4 https://urldefense.com/v3/__https://lore.kernel.org/linux-usb/1682393256-15572-1-git-send-email-quic_linyyuan@quicinc.com/__;!!A4F2R9G_pg!dIQ2VHccmZTXp1-59hTFfEhc65W0gatf1n2wmBfs5Yb0ipjHksD_ESQSmgXky1o1sc4wEZ5qp9JKV7IKmk5Km4ZXmsKSvQ$ )
> > > 1) rename suspend_irq_happen to suspended and document it
> > > 2) add old_link_state for link change interrupt usage and change accordingly
> > > 
> > > v4: (refer v3 https://urldefense.com/v3/__https://lore.kernel.org/linux-usb/1682053861-21737-1-git-send-email-quic_linyyuan@quicinc.com/__;!!A4F2R9G_pg!dIQ2VHccmZTXp1-59hTFfEhc65W0gatf1n2wmBfs5Yb0ipjHksD_ESQSmgXky1o1sc4wEZ5qp9JKV7IKmk5Km4aqWNUh-Q$ )
> > > 1) remove link state checking in dwc3_gadget_wakeup_interrupt()
> > > 2) remove two switch/case to if opeartion
> > > 
> > > v3: (refer v2 https://urldefense.com/v3/__https://lore.kernel.org/linux-usb/1682042472-21222-1-git-send-email-quic_linyyuan@quicinc.com/__;!!A4F2R9G_pg!dIQ2VHccmZTXp1-59hTFfEhc65W0gatf1n2wmBfs5Yb0ipjHksD_ESQSmgXky1o1sc4wEZ5qp9JKV7IKmk5Km4bRmn0HNA$ )
> > > no code change since v2, changes compare v1 as below,
> > > 1) add a flag suspend_irq_happen to simplify dwc3_gadget_suspend_interrupt(),
> > >     it will avoid refer to software level link_state, finally link_state will
> > >     only used in dwc3_gadget_linksts_change_interrupt().
> > > 2) remove sw setting of link_state in dwc3_gadget_func_wakeup()
> > > 3) add dwc3_gadget_interrupt_early() to correct setting of link_state
> > >     and suspend_irq_happen.
> > > 
> > > v2: update according v1 discussion
> > > v1: https://urldefense.com/v3/__https://lore.kernel.org/linux-usb/1675221286-23833-1-git-send-email-quic_linyyuan@quicinc.com/__;!!A4F2R9G_pg!dIQ2VHccmZTXp1-59hTFfEhc65W0gatf1n2wmBfs5Yb0ipjHksD_ESQSmgXky1o1sc4wEZ5qp9JKV7IKmk5Km4ZBn_TPEw$
> > > 
> > >   drivers/usb/dwc3/core.h   | 2 ++
> > >   drivers/usb/dwc3/gadget.c | 7 ++++++-
> > >   2 files changed, 8 insertions(+), 1 deletion(-)
> > > 
> > > diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
> > > index d56457c02996..efacaacbbeb2 100644
> > > --- a/drivers/usb/dwc3/core.h
> > > +++ b/drivers/usb/dwc3/core.h
> > > @@ -1116,6 +1116,7 @@ struct dwc3_scratchpad_array {
> > >    * @dis_metastability_quirk: set to disable metastability quirk.
> > >    * @dis_split_quirk: set to disable split boundary.
> > >    * @wakeup_configured: set if the device is configured for remote wakeup.
> > > + * @suspended: set if suspend irq happen to avoid possible consective suspend.
> > Can we rephrase to: "set to track suspend event due to U3/L2"
> 
> 
> thanks, sure.
> 
> 
> > 
> > >    * @imod_interval: set the interrupt moderation interval in 250ns
> > >    *			increments or 0 to disable.
> > >    * @max_cfg_eps: current max number of IN eps used across all USB configs.
> > > @@ -1332,6 +1333,7 @@ struct dwc3 {
> > >   	unsigned		dis_split_quirk:1;
> > >   	unsigned		async_callbacks:1;
> > >   	unsigned		wakeup_configured:1;
> > > +	unsigned		suspended:1;
> > >   	u16			imod_interval;
> > > diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
> > > index c0ca4d12f95d..2c750534b405 100644
> > > --- a/drivers/usb/dwc3/gadget.c
> > > +++ b/drivers/usb/dwc3/gadget.c
> > > @@ -4303,8 +4303,10 @@ static void dwc3_gadget_suspend_interrupt(struct dwc3 *dwc,
> > >   {
> > >   	enum dwc3_link_state next = evtinfo & DWC3_LINK_STATE_MASK;
> > > -	if (dwc->link_state != next && next == DWC3_LINK_STATE_U3)
> > > +	if (!dwc->suspended && next == DWC3_LINK_STATE_U3) {
> > > +		dwc->suspended = true;
> > >   		dwc3_suspend_gadget(dwc);
> > > +	}
> > >   	dwc->link_state = next;
> > >   }
> > > @@ -4312,6 +4314,9 @@ static void dwc3_gadget_suspend_interrupt(struct dwc3 *dwc,
> > >   static void dwc3_gadget_interrupt(struct dwc3 *dwc,
> > >   		const struct dwc3_event_devt *event)
> > >   {
> > > +	if  (event->type != DWC3_DEVICE_EVENT_SUSPEND)
> > Minor nit: spacing between if and (.
> 
> 
> thanks for point it out.
> 
> 
> > 
> > While this may work because the next suspend event won't come until a
> > resume/reset/disconnect event occur, let's clear this only on reset,
> > resume, and disconnect events.
> 
> 
> seem only clear on these three events is not correct.
> 
> how about suspend -> wakeup -> suspend interrupt sequences ?
> 
> this is mentioned in V1.
> 
> 

I meant "Wakeup" event, there's no resume event. When the host sends a
resume signal and the device is able to process it, then the driver gets
the Wakeup event.

Thanks,
Thinh
Thinh Nguyen May 8, 2023, 10:19 p.m. UTC | #2
On Mon, May 08, 2023, Thinh Nguyen wrote:
> On Mon, May 08, 2023, Linyu Yuan wrote:
> > 
> > On 5/6/2023 8:32 AM, Thinh Nguyen wrote:
> > > On Fri, May 05, 2023, Linyu Yuan wrote:
> > > > When work in gadget mode, currently driver doesn't update software level
> > > > link_state correctly as link state change event is not enabled for most
> > > > devices, in function dwc3_gadget_suspend_interrupt(), it will only pass
> > > > suspend event to UDC core when software level link state changes, so when
> > > > interrupt generated in sequences of suspend -> reset -> conndone ->
> > > > suspend, link state is not updated during reset and conndone, so second
> > > > suspend interrupt event will not pass to UDC core.
> > > > 
> > > > Remove link_state compare in dwc3_gadget_suspend_interrupt() and add a
> > > > suspended flag to replace the compare function.
> > > > 
> > > > Signed-off-by: Linyu Yuan <quic_linyyuan@quicinc.com>
> > > > ---
> > > > v6: (refer v5 https://urldefense.com/v3/__https://lore.kernel.org/linux-usb/1682476780-2367-1-git-send-email-quic_linyyuan@quicinc.com/__;!!A4F2R9G_pg!dIQ2VHccmZTXp1-59hTFfEhc65W0gatf1n2wmBfs5Yb0ipjHksD_ESQSmgXky1o1sc4wEZ5qp9JKV7IKmk5Km4bJzi2pGg$ )
> > > > 1) change subject
> > > > 2) only keep suspended flag related change
> > > > 
> > > > v5: (refer v4 https://urldefense.com/v3/__https://lore.kernel.org/linux-usb/1682393256-15572-1-git-send-email-quic_linyyuan@quicinc.com/__;!!A4F2R9G_pg!dIQ2VHccmZTXp1-59hTFfEhc65W0gatf1n2wmBfs5Yb0ipjHksD_ESQSmgXky1o1sc4wEZ5qp9JKV7IKmk5Km4ZXmsKSvQ$ )
> > > > 1) rename suspend_irq_happen to suspended and document it
> > > > 2) add old_link_state for link change interrupt usage and change accordingly
> > > > 
> > > > v4: (refer v3 https://urldefense.com/v3/__https://lore.kernel.org/linux-usb/1682053861-21737-1-git-send-email-quic_linyyuan@quicinc.com/__;!!A4F2R9G_pg!dIQ2VHccmZTXp1-59hTFfEhc65W0gatf1n2wmBfs5Yb0ipjHksD_ESQSmgXky1o1sc4wEZ5qp9JKV7IKmk5Km4aqWNUh-Q$ )
> > > > 1) remove link state checking in dwc3_gadget_wakeup_interrupt()
> > > > 2) remove two switch/case to if opeartion
> > > > 
> > > > v3: (refer v2 https://urldefense.com/v3/__https://lore.kernel.org/linux-usb/1682042472-21222-1-git-send-email-quic_linyyuan@quicinc.com/__;!!A4F2R9G_pg!dIQ2VHccmZTXp1-59hTFfEhc65W0gatf1n2wmBfs5Yb0ipjHksD_ESQSmgXky1o1sc4wEZ5qp9JKV7IKmk5Km4bRmn0HNA$ )
> > > > no code change since v2, changes compare v1 as below,
> > > > 1) add a flag suspend_irq_happen to simplify dwc3_gadget_suspend_interrupt(),
> > > >     it will avoid refer to software level link_state, finally link_state will
> > > >     only used in dwc3_gadget_linksts_change_interrupt().
> > > > 2) remove sw setting of link_state in dwc3_gadget_func_wakeup()
> > > > 3) add dwc3_gadget_interrupt_early() to correct setting of link_state
> > > >     and suspend_irq_happen.
> > > > 
> > > > v2: update according v1 discussion
> > > > v1: https://urldefense.com/v3/__https://lore.kernel.org/linux-usb/1675221286-23833-1-git-send-email-quic_linyyuan@quicinc.com/__;!!A4F2R9G_pg!dIQ2VHccmZTXp1-59hTFfEhc65W0gatf1n2wmBfs5Yb0ipjHksD_ESQSmgXky1o1sc4wEZ5qp9JKV7IKmk5Km4ZBn_TPEw$
> > > > 
> > > >   drivers/usb/dwc3/core.h   | 2 ++
> > > >   drivers/usb/dwc3/gadget.c | 7 ++++++-
> > > >   2 files changed, 8 insertions(+), 1 deletion(-)
> > > > 
> > > > diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
> > > > index d56457c02996..efacaacbbeb2 100644
> > > > --- a/drivers/usb/dwc3/core.h
> > > > +++ b/drivers/usb/dwc3/core.h
> > > > @@ -1116,6 +1116,7 @@ struct dwc3_scratchpad_array {
> > > >    * @dis_metastability_quirk: set to disable metastability quirk.
> > > >    * @dis_split_quirk: set to disable split boundary.
> > > >    * @wakeup_configured: set if the device is configured for remote wakeup.
> > > > + * @suspended: set if suspend irq happen to avoid possible consective suspend.
> > > Can we rephrase to: "set to track suspend event due to U3/L2"
> > 
> > 
> > thanks, sure.
> > 
> > 
> > > 
> > > >    * @imod_interval: set the interrupt moderation interval in 250ns
> > > >    *			increments or 0 to disable.
> > > >    * @max_cfg_eps: current max number of IN eps used across all USB configs.
> > > > @@ -1332,6 +1333,7 @@ struct dwc3 {
> > > >   	unsigned		dis_split_quirk:1;
> > > >   	unsigned		async_callbacks:1;
> > > >   	unsigned		wakeup_configured:1;
> > > > +	unsigned		suspended:1;
> > > >   	u16			imod_interval;
> > > > diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
> > > > index c0ca4d12f95d..2c750534b405 100644
> > > > --- a/drivers/usb/dwc3/gadget.c
> > > > +++ b/drivers/usb/dwc3/gadget.c
> > > > @@ -4303,8 +4303,10 @@ static void dwc3_gadget_suspend_interrupt(struct dwc3 *dwc,
> > > >   {
> > > >   	enum dwc3_link_state next = evtinfo & DWC3_LINK_STATE_MASK;
> > > > -	if (dwc->link_state != next && next == DWC3_LINK_STATE_U3)
> > > > +	if (!dwc->suspended && next == DWC3_LINK_STATE_U3) {
> > > > +		dwc->suspended = true;
> > > >   		dwc3_suspend_gadget(dwc);
> > > > +	}
> > > >   	dwc->link_state = next;
> > > >   }
> > > > @@ -4312,6 +4314,9 @@ static void dwc3_gadget_suspend_interrupt(struct dwc3 *dwc,
> > > >   static void dwc3_gadget_interrupt(struct dwc3 *dwc,
> > > >   		const struct dwc3_event_devt *event)
> > > >   {
> > > > +	if  (event->type != DWC3_DEVICE_EVENT_SUSPEND)
> > > Minor nit: spacing between if and (.
> > 
> > 
> > thanks for point it out.
> > 
> > 
> > > 
> > > While this may work because the next suspend event won't come until a
> > > resume/reset/disconnect event occur, let's clear this only on reset,
> > > resume, and disconnect events.
> > 
> > 
> > seem only clear on these three events is not correct.
> > 
> > how about suspend -> wakeup -> suspend interrupt sequences ?
> > 
> > this is mentioned in V1.
> > 
> > 
> 
> I meant "Wakeup" event, there's no resume event. When the host sends a
> resume signal and the device is able to process it, then the driver gets
> the Wakeup event.
> 

Actually, we do call it "resume/remote wakeup event", but we just named
it "wakeup" interrupt here in dwc3.

Another thing, can you clear the suspended flag when remote wakeup is
successful also?

Thanks,
Thinh
diff mbox series

Patch

diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index d56457c02996..efacaacbbeb2 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -1116,6 +1116,7 @@  struct dwc3_scratchpad_array {
  * @dis_metastability_quirk: set to disable metastability quirk.
  * @dis_split_quirk: set to disable split boundary.
  * @wakeup_configured: set if the device is configured for remote wakeup.
+ * @suspended: set if suspend irq happen to avoid possible consective suspend.
  * @imod_interval: set the interrupt moderation interval in 250ns
  *			increments or 0 to disable.
  * @max_cfg_eps: current max number of IN eps used across all USB configs.
@@ -1332,6 +1333,7 @@  struct dwc3 {
 	unsigned		dis_split_quirk:1;
 	unsigned		async_callbacks:1;
 	unsigned		wakeup_configured:1;
+	unsigned		suspended:1;
 
 	u16			imod_interval;
 
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index c0ca4d12f95d..2c750534b405 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -4303,8 +4303,10 @@  static void dwc3_gadget_suspend_interrupt(struct dwc3 *dwc,
 {
 	enum dwc3_link_state next = evtinfo & DWC3_LINK_STATE_MASK;
 
-	if (dwc->link_state != next && next == DWC3_LINK_STATE_U3)
+	if (!dwc->suspended && next == DWC3_LINK_STATE_U3) {
+		dwc->suspended = true;
 		dwc3_suspend_gadget(dwc);
+	}
 
 	dwc->link_state = next;
 }
@@ -4312,6 +4314,9 @@  static void dwc3_gadget_suspend_interrupt(struct dwc3 *dwc,
 static void dwc3_gadget_interrupt(struct dwc3 *dwc,
 		const struct dwc3_event_devt *event)
 {
+	if  (event->type != DWC3_DEVICE_EVENT_SUSPEND)
+		dwc->suspended = false;
+
 	switch (event->type) {
 	case DWC3_DEVICE_EVENT_DISCONNECT:
 		dwc3_gadget_disconnect_interrupt(dwc);