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@xxxxxxxxxx>
>> ---
>> 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.
