[PATCH 0/2] USB:ehci:fix the no SRBN register problem

[PATCH 0/2] USB:ehci:fix the no SRBN register problem

[Longfang Liu]

(1) Add a whitelist for EHCI devices without SBRN registers.
(2) Add Kunpeng920's EHCI device to the whitelist.

Longfang Liu (2):
  USB:ehci:Add a whitelist for EHCI controllers
  USB:ehci:fix Kunpeng920 ehci hardware problem

 drivers/usb/host/ehci-pci.c | 29 +++++++++++++++++++++++++----
 1 file changed, 25 insertions(+), 4 deletions(-)

-- 
2.8.1

[PATCH 1/2] USB:ehci:Add a whitelist for EHCI controllers

[Longfang Liu]

Some types of EHCI controllers do not have SBRN registers.
By comparing the white list, the operation of reading the SBRN
registers is skipped.

Subsequent EHCI controller types without SBRN registers can be
directly added to the white list.

The current patch does not affect the drive function.

Signed-off-by: Longfang Liu <liulongfang@huawei.com>
---
 drivers/usb/host/ehci-pci.c | 27 +++++++++++++++++++++++----
 1 file changed, 23 insertions(+), 4 deletions(-)

diff --git a/drivers/usb/host/ehci-pci.c b/drivers/usb/host/ehci-pci.c
index 3c3820a..6a30afa 100644
--- a/drivers/usb/host/ehci-pci.c
+++ b/drivers/usb/host/ehci-pci.c
@@ -47,6 +47,28 @@ static inline bool is_bypassed_id(struct pci_dev *pdev)
 	return !!pci_match_id(bypass_pci_id_table, pdev);
 }
 
+static const struct usb_nosbrn_whitelist_entry {
+	unsigned short vendor;
+	unsigned short device;
+} usb_nosbrn_whitelist[] = {
+	/* STMICRO ConneXT has no sbrn register */
+	{PCI_VENDOR_ID_STMICRO, PCI_DEVICE_ID_STMICRO_USB_HOST},
+	{}
+};
+
+static bool usb_nosbrn_whitelist_check(struct pci_dev *pdev)
+{
+	const struct usb_nosbrn_whitelist_entry *entry;
+
+	for (entry = usb_nosbrn_whitelist; entry->vendor; entry++) {
+		if (pdev->vendor == entry->vendor &&
+		    pdev->device == entry->device)
+			return true;
+	}
+
+	return false;
+}
+
 /*
  * 0x84 is the offset of in/out threshold register,
  * and it is the same offset as the register of 'hostpc'.
@@ -288,10 +310,7 @@ static int ehci_pci_setup(struct usb_hcd *hcd)
 	}
 
 	/* Serial Bus Release Number is at PCI 0x60 offset */
-	if (pdev->vendor == PCI_VENDOR_ID_STMICRO
-	    && pdev->device == PCI_DEVICE_ID_STMICRO_USB_HOST)
-		;	/* ConneXT has no sbrn register */
-	else
+	if (!usb_nosbrn_whitelist_check(pdev))
 		pci_read_config_byte(pdev, 0x60, &ehci->sbrn);
 
 	/* Keep this around for a while just in case some EHCI
-- 
2.8.1

Re: [PATCH 1/2] USB:ehci:Add a whitelist for EHCI controllers

[Greg KH]

On Thu, Apr 08, 2021 at 05:11:12PM +0800, Longfang Liu wrote:
> Some types of EHCI controllers do not have SBRN registers.
> By comparing the white list, the operation of reading the SBRN
> registers is skipped.
> 
> Subsequent EHCI controller types without SBRN registers can be
> directly added to the white list.
> 
> The current patch does not affect the drive function.
> 
> Signed-off-by: Longfang Liu <liulongfang@huawei.com>
> ---
>  drivers/usb/host/ehci-pci.c | 27 +++++++++++++++++++++++----
>  1 file changed, 23 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/usb/host/ehci-pci.c b/drivers/usb/host/ehci-pci.c
> index 3c3820a..6a30afa 100644
> --- a/drivers/usb/host/ehci-pci.c
> +++ b/drivers/usb/host/ehci-pci.c
> @@ -47,6 +47,28 @@ static inline bool is_bypassed_id(struct pci_dev *pdev)
>  	return !!pci_match_id(bypass_pci_id_table, pdev);
>  }
>  
> +static const struct usb_nosbrn_whitelist_entry {
> +	unsigned short vendor;
> +	unsigned short device;

u16 here please.

> +} usb_nosbrn_whitelist[] = {
> +	/* STMICRO ConneXT has no sbrn register */
> +	{PCI_VENDOR_ID_STMICRO, PCI_DEVICE_ID_STMICRO_USB_HOST},
> +	{}

trailing , please.

> +};
> +
> +static bool usb_nosbrn_whitelist_check(struct pci_dev *pdev)
> +{
> +	const struct usb_nosbrn_whitelist_entry *entry;
> +
> +	for (entry = usb_nosbrn_whitelist; entry->vendor; entry++) {
> +		if (pdev->vendor == entry->vendor &&
> +		    pdev->device == entry->device)
> +			return true;
> +	}
> +
> +	return false;
> +}
> +
>  /*
>   * 0x84 is the offset of in/out threshold register,
>   * and it is the same offset as the register of 'hostpc'.
> @@ -288,10 +310,7 @@ static int ehci_pci_setup(struct usb_hcd *hcd)
>  	}
>  
>  	/* Serial Bus Release Number is at PCI 0x60 offset */
> -	if (pdev->vendor == PCI_VENDOR_ID_STMICRO
> -	    && pdev->device == PCI_DEVICE_ID_STMICRO_USB_HOST)
> -		;	/* ConneXT has no sbrn register */
> -	else
> +	if (!usb_nosbrn_whitelist_check(pdev))

Doing this as a "negative" is hard to understand.  Should this just be:
	forbid_sbrn_read()
or something like that?

The term "whitelist" is not a good thing to use as it does not really
explain anything here.

thanks,

greg k-h

Re: [PATCH 1/2] USB:ehci:Add a whitelist for EHCI controllers

[liulongfang]

On 2021/4/8 17:22, Greg KH Wrote:
> On Thu, Apr 08, 2021 at 05:11:12PM +0800, Longfang Liu wrote:
>> Some types of EHCI controllers do not have SBRN registers.
>> By comparing the white list, the operation of reading the SBRN
>> registers is skipped.
>>
>> Subsequent EHCI controller types without SBRN registers can be
>> directly added to the white list.
>>
>> The current patch does not affect the drive function.
>>
>> Signed-off-by: Longfang Liu <liulongfang@huawei.com>
>> ---
>>  drivers/usb/host/ehci-pci.c | 27 +++++++++++++++++++++++----
>>  1 file changed, 23 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/usb/host/ehci-pci.c b/drivers/usb/host/ehci-pci.c
>> index 3c3820a..6a30afa 100644
>> --- a/drivers/usb/host/ehci-pci.c
>> +++ b/drivers/usb/host/ehci-pci.c
>> @@ -47,6 +47,28 @@ static inline bool is_bypassed_id(struct pci_dev *pdev)
>>  	return !!pci_match_id(bypass_pci_id_table, pdev);
>>  }
>>  
>> +static const struct usb_nosbrn_whitelist_entry {
>> +	unsigned short vendor;
>> +	unsigned short device;
> 
> u16 here please.
> 
>> +} usb_nosbrn_whitelist[] = {
>> +	/* STMICRO ConneXT has no sbrn register */
>> +	{PCI_VENDOR_ID_STMICRO, PCI_DEVICE_ID_STMICRO_USB_HOST},
>> +	{}
> 
> trailing , please.
> 

Is it necessary to add "," at the end here?

>> +};
>> +
>> +static bool usb_nosbrn_whitelist_check(struct pci_dev *pdev)
>> +{
>> +	const struct usb_nosbrn_whitelist_entry *entry;
>> +
>> +	for (entry = usb_nosbrn_whitelist; entry->vendor; entry++) {
>> +		if (pdev->vendor == entry->vendor &&
>> +		    pdev->device == entry->device)
>> +			return true;
>> +	}
>> +
>> +	return false;
>> +}
>> +
>>  /*
>>   * 0x84 is the offset of in/out threshold register,
>>   * and it is the same offset as the register of 'hostpc'.
>> @@ -288,10 +310,7 @@ static int ehci_pci_setup(struct usb_hcd *hcd)
>>  	}
>>  
>>  	/* Serial Bus Release Number is at PCI 0x60 offset */
>> -	if (pdev->vendor == PCI_VENDOR_ID_STMICRO
>> -	    && pdev->device == PCI_DEVICE_ID_STMICRO_USB_HOST)
>> -		;	/* ConneXT has no sbrn register */
>> -	else
>> +	if (!usb_nosbrn_whitelist_check(pdev))
> 
> Doing this as a "negative" is hard to understand.  Should this just be:
> 	forbid_sbrn_read()
> or something like that?
> 
> The term "whitelist" is not a good thing to use as it does not really
> explain anything here.
> 
> thanks,
> 
> greg k-h
> .
> 
Thanks
Longfang.

Re: [PATCH 1/2] USB:ehci:Add a whitelist for EHCI controllers

[Greg KH]

On Thu, Apr 08, 2021 at 09:04:17PM +0800, liulongfang wrote:
> On 2021/4/8 17:22, Greg KH Wrote:
> > On Thu, Apr 08, 2021 at 05:11:12PM +0800, Longfang Liu wrote:
> >> Some types of EHCI controllers do not have SBRN registers.
> >> By comparing the white list, the operation of reading the SBRN
> >> registers is skipped.
> >>
> >> Subsequent EHCI controller types without SBRN registers can be
> >> directly added to the white list.
> >>
> >> The current patch does not affect the drive function.
> >>
> >> Signed-off-by: Longfang Liu <liulongfang@huawei.com>
> >> ---
> >>  drivers/usb/host/ehci-pci.c | 27 +++++++++++++++++++++++----
> >>  1 file changed, 23 insertions(+), 4 deletions(-)
> >>
> >> diff --git a/drivers/usb/host/ehci-pci.c b/drivers/usb/host/ehci-pci.c
> >> index 3c3820a..6a30afa 100644
> >> --- a/drivers/usb/host/ehci-pci.c
> >> +++ b/drivers/usb/host/ehci-pci.c
> >> @@ -47,6 +47,28 @@ static inline bool is_bypassed_id(struct pci_dev *pdev)
> >>  	return !!pci_match_id(bypass_pci_id_table, pdev);
> >>  }
> >>  
> >> +static const struct usb_nosbrn_whitelist_entry {
> >> +	unsigned short vendor;
> >> +	unsigned short device;
> > 
> > u16 here please.
> > 
> >> +} usb_nosbrn_whitelist[] = {
> >> +	/* STMICRO ConneXT has no sbrn register */
> >> +	{PCI_VENDOR_ID_STMICRO, PCI_DEVICE_ID_STMICRO_USB_HOST},
> >> +	{}
> > 
> > trailing , please.
> > 
> 
> Is it necessary to add "," at the end here?

Yes please.

Re: [PATCH 1/2] USB:ehci:Add a whitelist for EHCI controllers

[Oliver Neukum]

Am Donnerstag, den 08.04.2021, 17:11 +0800 schrieb Longfang Liu:
> Some types of EHCI controllers do not have SBRN registers.
> By comparing the white list, the operation of reading the SBRN
> registers is skipped.
> 
> Subsequent EHCI controller types without SBRN registers can be
> directly added to the white list.

Hi,

shouldn't this set a flag for a missing functionality?

	Regards
		Oliver

Re: [PATCH 1/2] USB:ehci:Add a whitelist for EHCI controllers

[liulongfang]

On 2021/4/8 17:33, Oliver Neukum wrote:
> Am Donnerstag, den 08.04.2021, 17:11 +0800 schrieb Longfang Liu:
>> Some types of EHCI controllers do not have SBRN registers.
>> By comparing the white list, the operation of reading the SBRN
>> registers is skipped.
>>
>> Subsequent EHCI controller types without SBRN registers can be
>> directly added to the white list.
> 
> Hi,
> 
> shouldn't this set a flag for a missing functionality?
> 
> 	Regards
> 		Oliver
> 
> 
> .
> 
This flag is ehci->sbrn.
Thanks,
Longfang

[PATCH 2/2] USB:ehci:fix Kunpeng920 ehci hardware problem

[Longfang Liu]

Kunpeng920's EHCI controller does not have SBRN register.
Reading the SBRN register when the controller driver is
initialized will get 0.

When rebooting the EHCI driver, ehci_shutdown() will be called.
if the sbrn flag is 0, ehci_shutdown() will return directly.
The sbrn flag being 0 will cause the EHCI interrupt signal to
not be turned off after reboot. this interrupt that is not closed
will cause an exception to the device sharing the interrupt.

Therefore, the EHCI controller of kunpeng920 needs to be added
to the whitelist without SBRN register.

Signed-off-by: Longfang Liu <liulongfang@huawei.com>
---
 drivers/usb/host/ehci-pci.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/usb/host/ehci-pci.c b/drivers/usb/host/ehci-pci.c
index 6a30afa..c392a26 100644
--- a/drivers/usb/host/ehci-pci.c
+++ b/drivers/usb/host/ehci-pci.c
@@ -53,6 +53,8 @@ static const struct usb_nosbrn_whitelist_entry {
 } usb_nosbrn_whitelist[] = {
 	/* STMICRO ConneXT has no sbrn register */
 	{PCI_VENDOR_ID_STMICRO, PCI_DEVICE_ID_STMICRO_USB_HOST},
+	/* HUAWEI Kunpeng920 HiSilicon USB EHCI has no sbrn register */
+	{PCI_VENDOR_ID_HUAWEI, 0xa239},
 	{}
 };
 
-- 
2.8.1

[PATCH 0/2] USB:ehci:fix the no SRBN register problem

[Longfang Liu]

(1) Add a whitelist for EHCI devices without SBRN registers.
(2) Add Kunpeng920's EHCI device to the whitelist.

Longfang Liu (2):
  USB:ehci:Add a whitelist for EHCI controllers
  USB:ehci:fix Kunpeng920 ehci hardware problem

 drivers/usb/host/ehci-pci.c | 29 +++++++++++++++++++++++++----
 1 file changed, 25 insertions(+), 4 deletions(-)

-- 
2.8.1

[PATCH 1/2] USB:ehci:Add a whitelist for EHCI controllers

[Longfang Liu]

Some types of EHCI controllers do not have SBRN registers.
By comparing the white list, the operation of reading the SBRN
registers is skipped.

Subsequent EHCI controller types without SBRN registers can be
directly added to the white list.

The current patch does not affect the drive function.

Signed-off-by: Longfang Liu <liulongfang@huawei.com>
---
 drivers/usb/host/ehci-pci.c | 27 +++++++++++++++++++++++----
 1 file changed, 23 insertions(+), 4 deletions(-)

diff --git a/drivers/usb/host/ehci-pci.c b/drivers/usb/host/ehci-pci.c
index 3c3820a..6a30afa 100644
--- a/drivers/usb/host/ehci-pci.c
+++ b/drivers/usb/host/ehci-pci.c
@@ -47,6 +47,28 @@ static inline bool is_bypassed_id(struct pci_dev *pdev)
 	return !!pci_match_id(bypass_pci_id_table, pdev);
 }
 
+static const struct usb_nosbrn_whitelist_entry {
+	unsigned short vendor;
+	unsigned short device;
+} usb_nosbrn_whitelist[] = {
+	/* STMICRO ConneXT has no sbrn register */
+	{PCI_VENDOR_ID_STMICRO, PCI_DEVICE_ID_STMICRO_USB_HOST},
+	{}
+};
+
+static bool usb_nosbrn_whitelist_check(struct pci_dev *pdev)
+{
+	const struct usb_nosbrn_whitelist_entry *entry;
+
+	for (entry = usb_nosbrn_whitelist; entry->vendor; entry++) {
+		if (pdev->vendor == entry->vendor &&
+		    pdev->device == entry->device)
+			return true;
+	}
+
+	return false;
+}
+
 /*
  * 0x84 is the offset of in/out threshold register,
  * and it is the same offset as the register of 'hostpc'.
@@ -288,10 +310,7 @@ static int ehci_pci_setup(struct usb_hcd *hcd)
 	}
 
 	/* Serial Bus Release Number is at PCI 0x60 offset */
-	if (pdev->vendor == PCI_VENDOR_ID_STMICRO
-	    && pdev->device == PCI_DEVICE_ID_STMICRO_USB_HOST)
-		;	/* ConneXT has no sbrn register */
-	else
+	if (!usb_nosbrn_whitelist_check(pdev))
 		pci_read_config_byte(pdev, 0x60, &ehci->sbrn);
 
 	/* Keep this around for a while just in case some EHCI
-- 
2.8.1