Hi Lorenzo, On 13/02/19 8:06 PM, Lorenzo Pieralisi wrote: > On Wed, Feb 13, 2019 at 07:08:18PM +0530, Kishon Vijay Abraham I wrote: >> Hi Lorenzo, >> >> On 12/02/19 8:37 PM, Lorenzo Pieralisi wrote: >>> On Mon, Jan 07, 2019 at 12:11:44PM +0530, Kishon Vijay Abraham I wrote: >>> >>> [...] >>> >>>> static int pci_epf_test_bind(struct pci_epf *epf) >>>> { >>>> int ret; >>>> struct pci_epf_test *epf_test = epf_get_drvdata(epf); >>>> struct pci_epf_header *header = epf->header; >>>> + const struct pci_epc_features *epc_features; >>>> + enum pci_barno test_reg_bar = BAR_0; >>>> struct pci_epc *epc = epf->epc; >>>> struct device *dev = &epf->dev; >>>> + bool linkup_notifier = false; >>>> + bool msix_capable = false; >>>> + bool msi_capable = true; >>>> >>>> if (WARN_ON_ONCE(!epc)) >>>> return -EINVAL; >>>> >>>> - if (epc->features & EPC_FEATURE_NO_LINKUP_NOTIFIER) >>>> - epf_test->linkup_notifier = false; >>>> - else >>>> - epf_test->linkup_notifier = true; >>>> - >>>> - epf_test->msix_available = epc->features & EPC_FEATURE_MSIX_AVAILABLE; >>>> + epc_features = pci_epc_get_features(epc, epf->func_no); >>> >>> I think it would work out better if struct pci_epc_features was >>> allocated in the caller (stack) and pci_epc_get_features() take a >>> pointer parameter to it rather than the callee and the callee would just >>> have to fill it out, this also removes data in the driver that is not >>> really useful. >>> >>> Is there any other reason behind the current design choice ? >> >> Some drivers are used by multiple platforms each with different features. In >> such cases it's cleaner to have separate epc_feature table for each platform. >> >> I think the driver should maintain some sort of data to even populate >> pci_epc_features allocated by EP function driver. > > You mean that every EP controller driver should keep a table of > pci_epc_features (instead of a single instance) to be matched using DT > compatible strings to detect the platform variations ? Yes. Thanks Kishon