On Wed, Aug 09, 2023 at 07:28:51PM -0400, Alistair Francis wrote:
> The PCIe 6 specification added support for the Data Object Exchange (DOE).
> When DOE is supported the Discovery Data Object Protocol must be
> implemented. The protocol allows a requester to obtain information about
> the other DOE protocols supported by the device.
>
> The kernel is already querying the DOE protocols supported and cacheing
> the values. This patch exposes the values via sysfs. This will allow
> userspace to determine which DOE protocols are supported by the PCIe
> device.
>
> By exposing the information to userspace tools like lspci can relay the
> information to users. By listing all of the supported protocols we can
> allow userspace to parse and support the list, which might include
> vendor specific protocols as well as yet to be supported protocols.
>
> Signed-off-by: Alistair Francis <alistair.francis@xxxxxxx>
> ---
> v3:
> - Expose each DOE feature as a separate file
But you don't actually have anything in the sysfs files, why not?
> --- a/drivers/pci/doe.c
> +++ b/drivers/pci/doe.c
> @@ -56,6 +56,10 @@ struct pci_doe_mb {
> wait_queue_head_t wq;
> struct workqueue_struct *work_queue;
> unsigned long flags;
> +
> +#ifdef CONFIG_SYSFS
> + struct device_attribute *sysfs_attrs;
> +#endif
Please don't put #ifdefs in .c files if you can prevent it. I think
this will work just fine if you don't have the #ifdef. And who would be
using pci without sysfs?
> + attrs[i].attr.mode = 0444;
> + attrs[i].show = NULL;
Why set to NULL something that is already NULL? Did you just forget to
actually set the proper show callback here?
> +#ifdef CONFIG_PCI_DOE
> + retval = doe_sysfs_init(pdev);
> + if (retval)
> + return retval;
> +#endif
Again, no #ifdef in .c files please, put this in the .h file like
normal.
thanks,
greg k-h
