diff mbox series

usb: host: xhci: Do not re-initialize the XHCI HC if being removed

Message ID 20230523015354.18497-1-quic_wcheng@quicinc.com (mailing list archive)
State Superseded
Headers show
Series usb: host: xhci: Do not re-initialize the XHCI HC if being removed | expand

Commit Message

Wesley Cheng May 23, 2023, 1:53 a.m. UTC
During XHCI resume, if there was a host controller error detected the
routine will attempt to re-initialize the XHCI HC, so that it can return
back to an operational state.  If the XHCI host controller is being
removed, this sequence would be already handled within the XHCI halt path,
leading to a duplicate set of reg ops/calls.  In addition, since the XHCI
bus is being removed, the overhead added in restarting the HCD is
unnecessary.  Check for the XHC state before setting the reinit_xhc
parameter, which is responsible for triggering the restart.

Signed-off-by: Wesley Cheng <quic_wcheng@quicinc.com>
---
 drivers/usb/host/xhci.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Comments

Sergey Shtylyov May 23, 2023, 8:45 a.m. UTC | #1
Hello!

On 5/23/23 4:53 AM, Wesley Cheng wrote:

> During XHCI resume, if there was a host controller error detected the
> routine will attempt to re-initialize the XHCI HC, so that it can return
> back to an operational state.  If the XHCI host controller is being
> removed, this sequence would be already handled within the XHCI halt path,
> leading to a duplicate set of reg ops/calls.  In addition, since the XHCI
> bus is being removed, the overhead added in restarting the HCD is
> unnecessary.  Check for the XHC state before setting the reinit_xhc
> parameter, which is responsible for triggering the restart.
> 
> Signed-off-by: Wesley Cheng <quic_wcheng@quicinc.com>
> ---
>  drivers/usb/host/xhci.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
> index b81313ffeb76..2017ed3ae4a7 100644
> --- a/drivers/usb/host/xhci.c
> +++ b/drivers/usb/host/xhci.c
> @@ -1028,7 +1028,8 @@ int xhci_resume(struct xhci_hcd *xhci, pm_message_t msg)
>  	temp = readl(&xhci->op_regs->status);
>  
>  	/* re-initialize the HC on Restore Error, or Host Controller Error */
> -	if (temp & (STS_SRE | STS_HCE)) {
> +	if ((temp & (STS_SRE | STS_HCE)) &&
> +		!(xhci->xhc_state & XHCI_STATE_REMOVING)) {

  Please add one more tab here in order not to blend it with the following lines.

>  		reinit_xhc = true;
>  		if (!xhci->broken_suspend)
>  			xhci_warn(xhci, "xHC error in resume, USBSTS 0x%x, Reinit\n", temp);

MBR, Sergey
Greg KH May 23, 2023, 4:33 p.m. UTC | #2
On Tue, May 23, 2023 at 11:45:27AM +0300, Sergey Shtylyov wrote:
> Hello!
> 
> On 5/23/23 4:53 AM, Wesley Cheng wrote:
> 
> > During XHCI resume, if there was a host controller error detected the
> > routine will attempt to re-initialize the XHCI HC, so that it can return
> > back to an operational state.  If the XHCI host controller is being
> > removed, this sequence would be already handled within the XHCI halt path,
> > leading to a duplicate set of reg ops/calls.  In addition, since the XHCI
> > bus is being removed, the overhead added in restarting the HCD is
> > unnecessary.  Check for the XHC state before setting the reinit_xhc
> > parameter, which is responsible for triggering the restart.
> > 
> > Signed-off-by: Wesley Cheng <quic_wcheng@quicinc.com>
> > ---
> >  drivers/usb/host/xhci.c | 3 ++-
> >  1 file changed, 2 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
> > index b81313ffeb76..2017ed3ae4a7 100644
> > --- a/drivers/usb/host/xhci.c
> > +++ b/drivers/usb/host/xhci.c
> > @@ -1028,7 +1028,8 @@ int xhci_resume(struct xhci_hcd *xhci, pm_message_t msg)
> >  	temp = readl(&xhci->op_regs->status);
> >  
> >  	/* re-initialize the HC on Restore Error, or Host Controller Error */
> > -	if (temp & (STS_SRE | STS_HCE)) {
> > +	if ((temp & (STS_SRE | STS_HCE)) &&
> > +		!(xhci->xhc_state & XHCI_STATE_REMOVING)) {
> 
>   Please add one more tab here in order not to blend it with the following lines.

Ick, no, please do not do that, it needs to move left instead.

greg k-h
Sergey Shtylyov May 23, 2023, 4:42 p.m. UTC | #3
On 5/23/23 7:33 PM, Greg KH wrote:

>>> During XHCI resume, if there was a host controller error detected the
>>> routine will attempt to re-initialize the XHCI HC, so that it can return
>>> back to an operational state.  If the XHCI host controller is being
>>> removed, this sequence would be already handled within the XHCI halt path,
>>> leading to a duplicate set of reg ops/calls.  In addition, since the XHCI
>>> bus is being removed, the overhead added in restarting the HCD is
>>> unnecessary.  Check for the XHC state before setting the reinit_xhc
>>> parameter, which is responsible for triggering the restart.
>>>
>>> Signed-off-by: Wesley Cheng <quic_wcheng@quicinc.com>
>>> ---
>>>  drivers/usb/host/xhci.c | 3 ++-
>>>  1 file changed, 2 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
>>> index b81313ffeb76..2017ed3ae4a7 100644
>>> --- a/drivers/usb/host/xhci.c
>>> +++ b/drivers/usb/host/xhci.c
>>> @@ -1028,7 +1028,8 @@ int xhci_resume(struct xhci_hcd *xhci, pm_message_t msg)
>>>  	temp = readl(&xhci->op_regs->status);
>>>  
>>>  	/* re-initialize the HC on Restore Error, or Host Controller Error */
>>> -	if (temp & (STS_SRE | STS_HCE)) {
>>> +	if ((temp & (STS_SRE | STS_HCE)) &&
>>> +		!(xhci->xhc_state & XHCI_STATE_REMOVING)) {
>>
>>   Please add one more tab here in order not to blend it with the following lines.
> 
> Ick, no, please do not do that, it needs to move left instead.

   Don't we usually use 2 tabs to indent the continuation lines in the USB code?

> greg k-h

MBR, Sergey
diff mbox series

Patch

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index b81313ffeb76..2017ed3ae4a7 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -1028,7 +1028,8 @@  int xhci_resume(struct xhci_hcd *xhci, pm_message_t msg)
 	temp = readl(&xhci->op_regs->status);
 
 	/* re-initialize the HC on Restore Error, or Host Controller Error */
-	if (temp & (STS_SRE | STS_HCE)) {
+	if ((temp & (STS_SRE | STS_HCE)) &&
+		!(xhci->xhc_state & XHCI_STATE_REMOVING)) {
 		reinit_xhc = true;
 		if (!xhci->broken_suspend)
 			xhci_warn(xhci, "xHC error in resume, USBSTS 0x%x, Reinit\n", temp);