Re: [PATCH v5 3/9] PCI: endpoint: Pass EPF device ID to the probe function

From: Damien Le Moal
Date: Thu Jun 01 2023 - 19:16:53 EST


On 6/1/23 23:57, Manivannan Sadhasivam wrote:
> Currently, the EPF probe function doesn't get the device ID argument needed
> to correctly identify the device table ID of the EPF device.
>
> When multiple entries are added to the "struct pci_epf_device_id" table,
> the probe function needs to identify the correct one. This is achieved by
> modifying the pci_epf_match_id() function to return the match ID pointer
> and passing it to the driver's probe function.
>
> pci_epf_device_match() function can return bool based on the return value
> of pci_epf_match_id().
>
> Reviewed-by: Kishon Vijay Abraham I <kishon@xxxxxxxxxx>
> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>

[...]

> static int pci_epf_device_match(struct device *dev, struct device_driver *drv)
> @@ -510,8 +510,12 @@ static int pci_epf_device_match(struct device *dev, struct device_driver *drv)
> struct pci_epf *epf = to_pci_epf(dev);
> struct pci_epf_driver *driver = to_pci_epf_driver(drv);
>
> - if (driver->id_table)
> - return pci_epf_match_id(driver->id_table, epf);
> + if (driver->id_table) {
> + if (pci_epf_match_id(driver->id_table, epf))
> + return true;
> + else
> + return false;

return pci_epf_match_id(driver->id_table, epf) != NULL;

is simpler. If you do not like this, at least drop the "else" as it is not
necessary at all.

> + }
>
> return !strcmp(epf->name, drv->name);
> }
> @@ -520,13 +524,15 @@ static int pci_epf_device_probe(struct device *dev)
> {
> struct pci_epf *epf = to_pci_epf(dev);
> struct pci_epf_driver *driver = to_pci_epf_driver(dev->driver);
> + const struct pci_epf_device_id *id;
>
> if (!driver->probe)
> return -ENODEV;
>
> epf->driver = driver;
> + id = pci_epf_match_id(driver->id_table, epf);

Not sure that the id variable is that useful.

>
> - return driver->probe(epf);
> + return driver->probe(epf, id);
> }

--
Damien Le Moal
Western Digital Research