ID conflict between bdc_pci and "720p FaceTime HD Camera"

ID conflict between bdc_pci and "720p FaceTime HD Camera"

[Xavier Gnata]

Hello,

The development of a driver for
02:00.0 Multimedia controller [0480]: Broadcom Corporation 720p FaceTime 
HD Camera [14e4:1570]
has started. It is still in an early stage but it's progressing and it 
already streams.
https://github.com/patjak/bcwc_pcie

However, as you can see, this webcam shares the exact same ID as bdc_pci 
0x1570 .

Could we use e.g. PCI_CLASS in bdc_pci to avoid grabbing the webcam 
incorrectly?
The FaceTime HD Camera has PCI_CLASS 0x048000
I hope that bdc_pci has another PCI_CLASS.
Or maybe there is a better way to distinguish bdc_pci from FaceTime HD 
Camera. What do you think?

Regards,
Xavier

Re: ID conflict between bdc_pci and "720p FaceTime HD Camera"

[Bjorn Helgaas]

[+cc Ashwini, Felipe]

On Sun, Jan 17, 2016 at 04:35:30PM +0100, Xavier Gnata wrote:
> Hello,
> 
> The development of a driver for
> 02:00.0 Multimedia controller [0480]: Broadcom Corporation 720p
> FaceTime HD Camera [14e4:1570]
> has started. It is still in an early stage but it's progressing and
> it already streams.
> https://github.com/patjak/bcwc_pcie
> 
> However, as you can see, this webcam shares the exact same ID as
> bdc_pci 0x1570 .
> 
> Could we use e.g. PCI_CLASS in bdc_pci to avoid grabbing the webcam
> incorrectly?
> The FaceTime HD Camera has PCI_CLASS 0x048000
> I hope that bdc_pci has another PCI_CLASS.
> Or maybe there is a better way to distinguish bdc_pci from FaceTime
> HD Camera. What do you think?

This is what the PCI Vendor/Device IDs are for.  It's a shame that
Broadcom apparently screwed up and used the same IDs in two different
devices.

At least, I *assume* they're different.  I can't really tell what the
bdc_pci driver does, so it's conceivable that it's using the same
device in a different way than you are.

If they really are different devices, using the class code sounds like
a reasonable way to differentiate them.

Bjorn

Re: ID conflict between bdc_pci and "720p FaceTime HD Camera"

[Xavier Gnata]

On 19/01/2016 23:58, Bjorn Helgaas wrote:
> [+cc Ashwini, Felipe]
>
> On Sun, Jan 17, 2016 at 04:35:30PM +0100, Xavier Gnata wrote:
>> Hello,
>>
>> The development of a driver for
>> 02:00.0 Multimedia controller [0480]: Broadcom Corporation 720p
>> FaceTime HD Camera [14e4:1570]
>> has started. It is still in an early stage but it's progressing and
>> it already streams.
>> https://github.com/patjak/bcwc_pcie
>>
>> However, as you can see, this webcam shares the exact same ID as
>> bdc_pci 0x1570 .
>>
>> Could we use e.g. PCI_CLASS in bdc_pci to avoid grabbing the webcam
>> incorrectly?
>> The FaceTime HD Camera has PCI_CLASS 0x048000
>> I hope that bdc_pci has another PCI_CLASS.
>> Or maybe there is a better way to distinguish bdc_pci from FaceTime
>> HD Camera. What do you think?
>
> This is what the PCI Vendor/Device IDs are for.  It's a shame that
> Broadcom apparently screwed up and used the same IDs in two different
> devices.
>
> At least, I *assume* they're different.  I can't really tell what the
> bdc_pci driver does, so it's conceivable that it's using the same
> device in a different way than you are.
>
> If they really are different devices, using the class code sounds like
> a reasonable way to differentiate them.
>
> Bjorn
>

bdc is "Broadcom's USB3.0 device controller IP" in the SOC world which 
is connected through PCIe on FPGA-PCIe based platform.
Nothing to do with the Facetime HD webcam of a macbook air.
Broadcom screwed up.

The issue is that I don't have access to such a BDC.
I also don't find it in
http://pcidatabase.com/vendor_details.php?id=767
which lists 0x1570 as being the webcam.

Where can we find the PCI class of this "Broadcom's USB3.0 device 
controller IP" ? Ashwini?

Xavier