RE: [PATCH v5 04/15] PCI: Add pci_find_vsec_capability() to find a specific VSEC

Gustavo Pimentel
2021-02-11T19:44:14Z

On Thu, Feb 11, 2021 at 12:50:46, Krzysztof Wilczyński <kw@linux.com>
wrote:

> Hi Gustavo,
>
> [...]
> > + * Typically this function will be called by the pci driver, which passes
>
> It would be "PCI" here.

Nicely catch.

>
> > + * through argument the 'struct pci_dev *' already pointing for the device
> > + * config space that is associated with the vendor and device ID which will
> > + * know which ID to search and what to do with it, however, it might be
>
> Probably "there might be".

I've rephrased it.

>
> > + * cases that this function could be called outside of this scope and
> > + * therefore is the caller responsibility to check the vendor and/or
> [...]
>
> A suggestion. This commit message is a little hard to read and could be
> improved.
>
> It might just be me (by and large, and I am not a native English
> speaker), but it's actually easier to figure out what the function does
> after reading the implementation that from the comment. :)

I have also rephrased it. I hope it would be better, but I don't see how.

"Adds another helper to ones that already exist called
pci_find_vsec_capability. This helper crawls through the device PCI
config space searching for a specific ID on the Vendor-Specific Extended
Capabilities section.

The Vendor-Specific Extended Capability (VSEC) is a special PCI
capability (acts like container) defined by PCI-SIG that allows the one
or more proprietary capabilities defined by the vendor which aren't
standard or shared between the manufactures.

-Gustavo

>
> Krzysztof