Re: [PATCH net-next v3 1/2] pci: Add Cavium PCI vendor id

[David Miller <davem@davemloft.net>]

From: Bjorn Helgaas <bhelgaas@google.com>
Date: Mon, 18 May 2015 11:35:20 -0500

> [+cc Greg]
> 
> On Sat, May 16, 2015 at 4:14 PM, David Miller <davem@davemloft.net> wrote:
>> From: Bjorn Helgaas <bhelgaas@google.com>
>> Date: Sat, 16 May 2015 09:49:40 -0500
>>
>>> Hi Aleksey,
>>>
>>> On Fri, May 15, 2015 at 10:36 PM, Aleksey Makarov
>>> <aleksey.makarov@auriga.com> wrote:
>>>> Signed-off-by: Aleksey Makarov <aleksey.makarov@auriga.com>
>>>> ---
>>>>  include/linux/pci_ids.h | 2 ++
>>>>  1 file changed, 2 insertions(+)
>>>>
>>>> diff --git a/include/linux/pci_ids.h b/include/linux/pci_ids.h
>>>> index e63c02a..3633cc6 100644
>>>> --- a/include/linux/pci_ids.h
>>>> +++ b/include/linux/pci_ids.h
>>>> @@ -2327,6 +2327,8 @@
>>>>  #define PCI_DEVICE_ID_ALTIMA_AC9100    0x03ea
>>>>  #define PCI_DEVICE_ID_ALTIMA_AC1003    0x03eb
>>>>
>>>> +#define PCI_VENDOR_ID_CAVIUM           0x177d
>>>
>>> Please read the note at the top of include/linux/pci_ids.h.  If this
>>> definition is used in two or more drivers, mention that in the
>>> changelog.  Otherwise, just use the bare hex value or a private
>>> #define in your driver.
>>
>> It is referenced from two foo.c files in the same driver.
>>
>> I don't know what policy we want for situations like that.
> 
> The current policy (1d4a433fc4e9 ("PCI: Document pci_ids.h addition
> policy.")) predates me and I don't know the whole rationale.  I can
> see that it might reduce backporting pain for distros.
> 
> If two foo.c files in the same driver share the PCI ID, they likely
> share other things as well, so there's likely a shared .h file where a
> private PCI_VENDOR_ID_CAVIUM could go.
> 
> But this is a vendor ID (not a device ID), and it seems likely that
> there will be other devices from Cavium, so maybe it would make sense
> to apply the policy to device IDs, and go ahead and add vendor IDs to
> pci_ids.h.

That makes sense to me, and therefore this change is probably fine as-is.