[PATCH v2] usb: dwc3: core: Stop processing of pending events if controller is halted

[PATCH v2] usb: dwc3: core: Stop processing of pending events if controller is halted

[Selvarasu Ganesan]

This commit addresses an issue where events were being processed when
the controller was in a halted state. To fix this issue by stop
processing the events as the event count was considered stale or
invalid when the controller was halted.

Fixes: fc8bb91bc83e ("usb: dwc3: implement runtime PM")
Cc: stable <stable@kernel.org>
Signed-off-by: Selvarasu Ganesan <selvarasu.g@samsung.com>
Suggested-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
---

Changes in v2:
- Updated the code changes that suggested by reviewer (Thinh Nguyen).
- Link to v1: https://lore.kernel.org/lkml/20240719110100.329-1-selvarasu.g@samsung.com/
---
 drivers/usb/dwc3/core.c   | 22 +++++++++++++++++++---
 drivers/usb/dwc3/core.h   |  4 ----
 drivers/usb/dwc3/gadget.c | 11 -----------
 3 files changed, 19 insertions(+), 18 deletions(-)

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 9eb085f359ce..65ae5203b89e 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -544,6 +544,7 @@ static int dwc3_alloc_event_buffers(struct dwc3 *dwc, unsigned int length)
 int dwc3_event_buffers_setup(struct dwc3 *dwc)
 {
 	struct dwc3_event_buffer	*evt;
+	u32				reg;
 
 	if (!dwc->ev_buf)
 		return 0;
@@ -556,8 +557,10 @@ int dwc3_event_buffers_setup(struct dwc3 *dwc)
 			upper_32_bits(evt->dma));
 	dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(0),
 			DWC3_GEVNTSIZ_SIZE(evt->length));
-	dwc3_writel(dwc->regs, DWC3_GEVNTCOUNT(0), 0);
 
+	/* Clear any stale event */
+	reg = dwc3_readl(dwc->regs, DWC3_GEVNTCOUNT(0));
+	dwc3_writel(dwc->regs, DWC3_GEVNTCOUNT(0), reg);
 	return 0;
 }
 
@@ -584,7 +587,10 @@ void dwc3_event_buffers_cleanup(struct dwc3 *dwc)
 	dwc3_writel(dwc->regs, DWC3_GEVNTADRHI(0), 0);
 	dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(0), DWC3_GEVNTSIZ_INTMASK
 			| DWC3_GEVNTSIZ_SIZE(0));
-	dwc3_writel(dwc->regs, DWC3_GEVNTCOUNT(0), 0);
+
+	/* Clear any stale event */
+	reg = dwc3_readl(dwc->regs, DWC3_GEVNTCOUNT(0));
+	dwc3_writel(dwc->regs, DWC3_GEVNTCOUNT(0), reg);
 }
 
 static void dwc3_core_num_eps(struct dwc3 *dwc)
@@ -2499,7 +2505,11 @@ static int dwc3_runtime_resume(struct device *dev)
 
 	switch (dwc->current_dr_role) {
 	case DWC3_GCTL_PRTCAP_DEVICE:
-		dwc3_gadget_process_pending_events(dwc);
+		if (dwc->pending_events) {
+			pm_runtime_put(dwc->dev);
+			dwc->pending_events = false;
+			enable_irq(dwc->irq_gadget);
+		}
 		break;
 	case DWC3_GCTL_PRTCAP_HOST:
 	default:
@@ -2589,6 +2599,12 @@ static void dwc3_complete(struct device *dev)
 static const struct dev_pm_ops dwc3_dev_pm_ops = {
 	SET_SYSTEM_SLEEP_PM_OPS(dwc3_suspend, dwc3_resume)
 	.complete = dwc3_complete,
+
+	/*
+	 * Runtime suspend halts the controller on disconnection. It replies on
+	 * platforms with custom connection notification to start the controller
+	 * again.
+	 */
 	SET_RUNTIME_PM_OPS(dwc3_runtime_suspend, dwc3_runtime_resume,
 			dwc3_runtime_idle)
 };
diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index c71240e8f7c7..9c508e0c5cdf 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -1675,7 +1675,6 @@ static inline void dwc3_otg_host_init(struct dwc3 *dwc)
 #if !IS_ENABLED(CONFIG_USB_DWC3_HOST)
 int dwc3_gadget_suspend(struct dwc3 *dwc);
 int dwc3_gadget_resume(struct dwc3 *dwc);
-void dwc3_gadget_process_pending_events(struct dwc3 *dwc);
 #else
 static inline int dwc3_gadget_suspend(struct dwc3 *dwc)
 {
@@ -1687,9 +1686,6 @@ static inline int dwc3_gadget_resume(struct dwc3 *dwc)
 	return 0;
 }
 
-static inline void dwc3_gadget_process_pending_events(struct dwc3 *dwc)
-{
-}
 #endif /* !IS_ENABLED(CONFIG_USB_DWC3_HOST) */
 
 #if IS_ENABLED(CONFIG_USB_DWC3_ULPI)
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 291bc549935b..10178e5eda5a 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -4728,14 +4728,3 @@ int dwc3_gadget_resume(struct dwc3 *dwc)
 
 	return dwc3_gadget_soft_connect(dwc);
 }
-
-void dwc3_gadget_process_pending_events(struct dwc3 *dwc)
-{
-	if (dwc->pending_events) {
-		dwc3_interrupt(dwc->irq_gadget, dwc->ev_buf);
-		dwc3_thread_interrupt(dwc->irq_gadget, dwc->ev_buf);
-		pm_runtime_put(dwc->dev);
-		dwc->pending_events = false;
-		enable_irq(dwc->irq_gadget);
-	}
-}
-- 
2.17.1

Re: [PATCH v2] usb: dwc3: core: Stop processing of pending events if controller is halted

[Thinh Nguyen]

On Tue, Sep 17, 2024, Selvarasu Ganesan wrote:
> This commit addresses an issue where events were being processed when
> the controller was in a halted state. To fix this issue by stop
> processing the events as the event count was considered stale or
> invalid when the controller was halted.
> 
> Fixes: fc8bb91bc83e ("usb: dwc3: implement runtime PM")
> Cc: stable <stable@kernel.org>

Checkpatch doesn't like that format. Fix the Cc stable tag to below:

Cc: stable@kernel.org

> Signed-off-by: Selvarasu Ganesan <selvarasu.g@samsung.com>
> Suggested-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
> ---
> 
> Changes in v2:
> - Updated the code changes that suggested by reviewer (Thinh Nguyen).
> - Link to v1: https://urldefense.com/v3/__https://lore.kernel.org/lkml/20240719110100.329-1-selvarasu.g@samsung.com/__;!!A4F2R9G_pg!bSbBiyBT0X0C8o_Q7P_-KRqpOSZyigMiFe3hDcu78KnopsRHQrLIuOPVU3TZT-jqNHAn2z-U6c6SVEcmr3faZNMd3vU$ 
> ---
>  drivers/usb/dwc3/core.c   | 22 +++++++++++++++++++---
>  drivers/usb/dwc3/core.h   |  4 ----
>  drivers/usb/dwc3/gadget.c | 11 -----------
>  3 files changed, 19 insertions(+), 18 deletions(-)
> 
> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> index 9eb085f359ce..65ae5203b89e 100644
> --- a/drivers/usb/dwc3/core.c
> +++ b/drivers/usb/dwc3/core.c
> @@ -544,6 +544,7 @@ static int dwc3_alloc_event_buffers(struct dwc3 *dwc, unsigned int length)
>  int dwc3_event_buffers_setup(struct dwc3 *dwc)
>  {
>  	struct dwc3_event_buffer	*evt;
> +	u32				reg;
>  
>  	if (!dwc->ev_buf)
>  		return 0;
> @@ -556,8 +557,10 @@ int dwc3_event_buffers_setup(struct dwc3 *dwc)
>  			upper_32_bits(evt->dma));
>  	dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(0),
>  			DWC3_GEVNTSIZ_SIZE(evt->length));
> -	dwc3_writel(dwc->regs, DWC3_GEVNTCOUNT(0), 0);
>  
> +	/* Clear any stale event */
> +	reg = dwc3_readl(dwc->regs, DWC3_GEVNTCOUNT(0));
> +	dwc3_writel(dwc->regs, DWC3_GEVNTCOUNT(0), reg);
>  	return 0;
>  }
>  
> @@ -584,7 +587,10 @@ void dwc3_event_buffers_cleanup(struct dwc3 *dwc)
>  	dwc3_writel(dwc->regs, DWC3_GEVNTADRHI(0), 0);
>  	dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(0), DWC3_GEVNTSIZ_INTMASK
>  			| DWC3_GEVNTSIZ_SIZE(0));
> -	dwc3_writel(dwc->regs, DWC3_GEVNTCOUNT(0), 0);
> +
> +	/* Clear any stale event */
> +	reg = dwc3_readl(dwc->regs, DWC3_GEVNTCOUNT(0));
> +	dwc3_writel(dwc->regs, DWC3_GEVNTCOUNT(0), reg);
>  }
>  
>  static void dwc3_core_num_eps(struct dwc3 *dwc)
> @@ -2499,7 +2505,11 @@ static int dwc3_runtime_resume(struct device *dev)
>  
>  	switch (dwc->current_dr_role) {
>  	case DWC3_GCTL_PRTCAP_DEVICE:
> -		dwc3_gadget_process_pending_events(dwc);
> +		if (dwc->pending_events) {
> +			pm_runtime_put(dwc->dev);
> +			dwc->pending_events = false;
> +			enable_irq(dwc->irq_gadget);
> +		}
>  		break;
>  	case DWC3_GCTL_PRTCAP_HOST:
>  	default:
> @@ -2589,6 +2599,12 @@ static void dwc3_complete(struct device *dev)
>  static const struct dev_pm_ops dwc3_dev_pm_ops = {
>  	SET_SYSTEM_SLEEP_PM_OPS(dwc3_suspend, dwc3_resume)
>  	.complete = dwc3_complete,
> +
> +	/*
> +	 * Runtime suspend halts the controller on disconnection. It replies on

Fix replies -> relies

> +	 * platforms with custom connection notification to start the controller
> +	 * again.
> +	 */
>  	SET_RUNTIME_PM_OPS(dwc3_runtime_suspend, dwc3_runtime_resume,
>  			dwc3_runtime_idle)
>  };
> diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
> index c71240e8f7c7..9c508e0c5cdf 100644
> --- a/drivers/usb/dwc3/core.h
> +++ b/drivers/usb/dwc3/core.h
> @@ -1675,7 +1675,6 @@ static inline void dwc3_otg_host_init(struct dwc3 *dwc)
>  #if !IS_ENABLED(CONFIG_USB_DWC3_HOST)
>  int dwc3_gadget_suspend(struct dwc3 *dwc);
>  int dwc3_gadget_resume(struct dwc3 *dwc);
> -void dwc3_gadget_process_pending_events(struct dwc3 *dwc);
>  #else
>  static inline int dwc3_gadget_suspend(struct dwc3 *dwc)
>  {
> @@ -1687,9 +1686,6 @@ static inline int dwc3_gadget_resume(struct dwc3 *dwc)
>  	return 0;
>  }
>  
> -static inline void dwc3_gadget_process_pending_events(struct dwc3 *dwc)
> -{
> -}
>  #endif /* !IS_ENABLED(CONFIG_USB_DWC3_HOST) */
>  
>  #if IS_ENABLED(CONFIG_USB_DWC3_ULPI)
> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
> index 291bc549935b..10178e5eda5a 100644
> --- a/drivers/usb/dwc3/gadget.c
> +++ b/drivers/usb/dwc3/gadget.c
> @@ -4728,14 +4728,3 @@ int dwc3_gadget_resume(struct dwc3 *dwc)
>  
>  	return dwc3_gadget_soft_connect(dwc);
>  }
> -
> -void dwc3_gadget_process_pending_events(struct dwc3 *dwc)
> -{
> -	if (dwc->pending_events) {
> -		dwc3_interrupt(dwc->irq_gadget, dwc->ev_buf);
> -		dwc3_thread_interrupt(dwc->irq_gadget, dwc->ev_buf);
> -		pm_runtime_put(dwc->dev);
> -		dwc->pending_events = false;
> -		enable_irq(dwc->irq_gadget);
> -	}
> -}
> -- 
> 2.17.1
> 

After the minor fixes, you can include this:

Acked-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>

Thanks,
Thinh

Re: [PATCH v2] usb: dwc3: core: Stop processing of pending events if controller is halted

[gregkh]

On Mon, Sep 16, 2024 at 11:00:30PM +0000, Thinh Nguyen wrote:
> On Tue, Sep 17, 2024, Selvarasu Ganesan wrote:
> > This commit addresses an issue where events were being processed when
> > the controller was in a halted state. To fix this issue by stop
> > processing the events as the event count was considered stale or
> > invalid when the controller was halted.
> > 
> > Fixes: fc8bb91bc83e ("usb: dwc3: implement runtime PM")
> > Cc: stable <stable@kernel.org>
> 
> Checkpatch doesn't like that format. Fix the Cc stable tag to below:
> 
> Cc: stable@kernel.org

What?  Why?  That should be fine, exactly what is the warning that this
gives?  That should be fine, as it's what my scripts put into patches
that I create :)

thanks,

greg k-h

Re: [PATCH v2] usb: dwc3: core: Stop processing of pending events if controller is halted

[Thinh Nguyen]

On Tue, Sep 17, 2024, gregkh@linuxfoundation.org wrote:
> On Mon, Sep 16, 2024 at 11:00:30PM +0000, Thinh Nguyen wrote:
> > On Tue, Sep 17, 2024, Selvarasu Ganesan wrote:
> > > This commit addresses an issue where events were being processed when
> > > the controller was in a halted state. To fix this issue by stop
> > > processing the events as the event count was considered stale or
> > > invalid when the controller was halted.
> > > 
> > > Fixes: fc8bb91bc83e ("usb: dwc3: implement runtime PM")
> > > Cc: stable <stable@kernel.org>
> > 
> > Checkpatch doesn't like that format. Fix the Cc stable tag to below:
> > 
> > Cc: stable@kernel.org
> 
> What?  Why?  That should be fine, exactly what is the warning that this
> gives?  That should be fine, as it's what my scripts put into patches
> that I create :)
> 

This is what checkpatch complains:

WARNING:BAD_STABLE_ADDRESS_STYLE: Invalid email format for stable: 'stable <stable@kernel.org>', prefer 'stable@kernel.org'
#23: 
Cc: stable <stable@kernel.org>

total: 0 errors, 1 warnings, 0 checks, 72 lines checked

BR,
Thinh

Re: [PATCH v2] usb: dwc3: core: Stop processing of pending events if controller is halted

[gregkh]

On Tue, Sep 17, 2024 at 05:47:05AM +0000, Thinh Nguyen wrote:
> On Tue, Sep 17, 2024, gregkh@linuxfoundation.org wrote:
> > On Mon, Sep 16, 2024 at 11:00:30PM +0000, Thinh Nguyen wrote:
> > > On Tue, Sep 17, 2024, Selvarasu Ganesan wrote:
> > > > This commit addresses an issue where events were being processed when
> > > > the controller was in a halted state. To fix this issue by stop
> > > > processing the events as the event count was considered stale or
> > > > invalid when the controller was halted.
> > > > 
> > > > Fixes: fc8bb91bc83e ("usb: dwc3: implement runtime PM")
> > > > Cc: stable <stable@kernel.org>
> > > 
> > > Checkpatch doesn't like that format. Fix the Cc stable tag to below:
> > > 
> > > Cc: stable@kernel.org
> > 
> > What?  Why?  That should be fine, exactly what is the warning that this
> > gives?  That should be fine, as it's what my scripts put into patches
> > that I create :)
> > 
> 
> This is what checkpatch complains:
> 
> WARNING:BAD_STABLE_ADDRESS_STYLE: Invalid email format for stable: 'stable <stable@kernel.org>', prefer 'stable@kernel.org'
> #23: 
> Cc: stable <stable@kernel.org>
> 
> total: 0 errors, 1 warnings, 0 checks, 72 lines checked

Ugh, that's wrong, whatever you want to do here is fine.

Someone should send a patch for checkpatch...

thanks,

greg k-h

Re: [PATCH v2] usb: dwc3: core: Stop processing of pending events if controller is halted

[Selvarasu Ganesan]

On 9/17/2024 12:38 PM, gregkh@linuxfoundation.org wrote:
> On Tue, Sep 17, 2024 at 05:47:05AM +0000, Thinh Nguyen wrote:
>> On Tue, Sep 17, 2024, gregkh@linuxfoundation.org wrote:
>>> On Mon, Sep 16, 2024 at 11:00:30PM +0000, Thinh Nguyen wrote:
>>>> On Tue, Sep 17, 2024, Selvarasu Ganesan wrote:
>>>>> This commit addresses an issue where events were being processed when
>>>>> the controller was in a halted state. To fix this issue by stop
>>>>> processing the events as the event count was considered stale or
>>>>> invalid when the controller was halted.
>>>>>
>>>>> Fixes: fc8bb91bc83e ("usb: dwc3: implement runtime PM")
>>>>> Cc: stable <stable@kernel.org>
>>>> Checkpatch doesn't like that format. Fix the Cc stable tag to below:
>>>>
>>>> Cc: stable@kernel.org
>>> What?  Why?  That should be fine, exactly what is the warning that this
>>> gives?  That should be fine, as it's what my scripts put into patches
>>> that I create :)
>>>
>> This is what checkpatch complains:
>>
>> WARNING:BAD_STABLE_ADDRESS_STYLE: Invalid email format for stable: 'stable <stable@kernel.org>', prefer 'stable@kernel.org'
>> #23:
>> Cc: stable <stable@kernel.org>
>>
>> total: 0 errors, 1 warnings, 0 checks, 72 lines checked
> Ugh, that's wrong, whatever you want to do here is fine.
>
> Someone should send a patch for checkpatch...
>
> thanks,
>
> greg k-h

Hi Greg,

However I already posted new version with address a typo mistake as 
well. Kindly review the same.

https://lore.kernel.org/lkml/20240916231813.206-1-selvarasu.g@samsung.com/

Thanks,
Selva
>

Re: [PATCH v2] usb: dwc3: core: Stop processing of pending events if controller is halted

[gregkh]

On Tue, Sep 17, 2024 at 09:52:00PM +0530, Selvarasu Ganesan wrote:
> 
> On 9/17/2024 12:38 PM, gregkh@linuxfoundation.org wrote:
> > On Tue, Sep 17, 2024 at 05:47:05AM +0000, Thinh Nguyen wrote:
> >> On Tue, Sep 17, 2024, gregkh@linuxfoundation.org wrote:
> >>> On Mon, Sep 16, 2024 at 11:00:30PM +0000, Thinh Nguyen wrote:
> >>>> On Tue, Sep 17, 2024, Selvarasu Ganesan wrote:
> >>>>> This commit addresses an issue where events were being processed when
> >>>>> the controller was in a halted state. To fix this issue by stop
> >>>>> processing the events as the event count was considered stale or
> >>>>> invalid when the controller was halted.
> >>>>>
> >>>>> Fixes: fc8bb91bc83e ("usb: dwc3: implement runtime PM")
> >>>>> Cc: stable <stable@kernel.org>
> >>>> Checkpatch doesn't like that format. Fix the Cc stable tag to below:
> >>>>
> >>>> Cc: stable@kernel.org
> >>> What?  Why?  That should be fine, exactly what is the warning that this
> >>> gives?  That should be fine, as it's what my scripts put into patches
> >>> that I create :)
> >>>
> >> This is what checkpatch complains:
> >>
> >> WARNING:BAD_STABLE_ADDRESS_STYLE: Invalid email format for stable: 'stable <stable@kernel.org>', prefer 'stable@kernel.org'
> >> #23:
> >> Cc: stable <stable@kernel.org>
> >>
> >> total: 0 errors, 1 warnings, 0 checks, 72 lines checked
> > Ugh, that's wrong, whatever you want to do here is fine.
> >
> > Someone should send a patch for checkpatch...
> >
> > thanks,
> >
> > greg k-h
> 
> Hi Greg,
> 
> However I already posted new version with address a typo mistake as 
> well. Kindly review the same.
> 
> https://lore.kernel.org/lkml/20240916231813.206-1-selvarasu.g@samsung.com/

It's the middle of the merge window, I'll look at it after -rc1 is out,
thanks.

greg k-h

Re: [PATCH v2] usb: dwc3: core: Stop processing of pending events if controller is halted

[Thinh Nguyen]

++Joe Perches, Dwaipayan Ray

On Tue, Sep 17, 2024, gregkh@linuxfoundation.org wrote:
> On Tue, Sep 17, 2024 at 05:47:05AM +0000, Thinh Nguyen wrote:
> > On Tue, Sep 17, 2024, gregkh@linuxfoundation.org wrote:
> > > On Mon, Sep 16, 2024 at 11:00:30PM +0000, Thinh Nguyen wrote:
> > > > On Tue, Sep 17, 2024, Selvarasu Ganesan wrote:
> > > > > This commit addresses an issue where events were being processed when
> > > > > the controller was in a halted state. To fix this issue by stop
> > > > > processing the events as the event count was considered stale or
> > > > > invalid when the controller was halted.
> > > > > 
> > > > > Fixes: fc8bb91bc83e ("usb: dwc3: implement runtime PM")
> > > > > Cc: stable <stable@kernel.org>
> > > > 
> > > > Checkpatch doesn't like that format. Fix the Cc stable tag to below:
> > > > 
> > > > Cc: stable@kernel.org
> > > 
> > > What?  Why?  That should be fine, exactly what is the warning that this
> > > gives?  That should be fine, as it's what my scripts put into patches
> > > that I create :)
> > > 
> > 
> > This is what checkpatch complains:
> > 
> > WARNING:BAD_STABLE_ADDRESS_STYLE: Invalid email format for stable: 'stable <stable@kernel.org>', prefer 'stable@kernel.org'
> > #23: 
> > Cc: stable <stable@kernel.org>
> > 
> > total: 0 errors, 1 warnings, 0 checks, 72 lines checked
> 
> Ugh, that's wrong, whatever you want to do here is fine.
> 
> Someone should send a patch for checkpatch...
> 

I included the maintainer Joe and Dwaipayan base on the below related change:
fccaebf00e60 ("checkpatch: improve email parsing")

Seems checkpatch doesn't like stable address that begins with a name?
Hopefully they can help take a look.

Thanks,
Thinh