On Thu, Sep 30, 2021 at 06:28:12PM -0700, David E. Box wrote: > Intel Platform Monitoring Technology (PMT) support is indicated by presence > of an Intel defined PCIe DVSEC structure with a PMT ID. However DVSEC > structures may also be used by Intel to indicate support for other > capabilities unrelated to PMT. The Out Of Band Management Services Module > (OOBMSM) is an example of a device that can have both PMT and non-PMT > capabilities. In order to support these capabilities it is necessary to > modify the intel_pmt driver to handle the creation of platform devices more > generically. To that end the following changes are made. > > Convert the driver and child drivers from MFD to the Auxiliary Bus. This > architecture is more suitable anyway since the driver partitions a > multifunctional PCIe device. This also moves the driver out of the MFD > subsystem and into platform/x86/intel. > > Before, devices were named by their capability (e.g. pmt_telemetry). > Instead, generically name them by their capability ID (e.g. > intel_extended_cap.2). This allows the IDs to be created automatically, > minimizing the code needed to support future capabilities. However, to > ensure that unsupported devices aren't created, use an allow list to > specify supported capabilities. Along these lines, rename the driver from > intel_pmt to intel_extended_caps to better reflect the purpose. > > Signed-off-by: David E. Box <david.e.box@xxxxxxxxxxxxxxx> > --- > > V1: New patch. However incorporates some elements of [1] which was > dropped. Namely enumerating features generically and creating an > allow list. Also cleans up probe by moving some code to functions > and using a bool instead of an int to track whether a device was > added. > > [1] https://lore.kernel.org/all/20210922213007.2738388-3-david.e.box@xxxxxxxxxxxxxxx/ <...> > +static int extended_caps_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) > +{ > + struct extended_caps_platform_info *info; > + bool have_devices = false; > + unsigned long quirks = 0; > + int ret; > + > + ret = pcim_enable_device(pdev); > + if (ret) > + return ret; > + > + info = (struct extended_caps_platform_info *)id->driver_data; pci_get_drvdata() in all places and no need to cast void *. > + if (info) > + quirks = info->quirks; > + > + have_devices |= extended_caps_walk_dvsec(pdev, quirks); > + > + if (info && (info->quirks & EXT_CAPS_QUIRK_NO_DVSEC)) > + have_devices |= extended_caps_walk_header(pdev, quirks, info->capabilities); > + > + if (!have_devices) > + return -ENODEV; > + > + return 0; > +} <...> > -static struct platform_driver pmt_telem_driver = { > - .driver = { > - .name = TELEM_DEV_NAME, > - }, > - .remove = pmt_telem_remove, > - .probe = pmt_telem_probe, > +static const struct auxiliary_device_id pmt_telem_aux_id_table[] = { > + { .name = "intel_extended_caps.2", }, Why "2" in the name? Thanks > + {}, > +}; > +MODULE_DEVICE_TABLE(auxiliary, pmt_telem_aux_id_table); > + > +static struct auxiliary_driver pmt_telem_aux_driver = { > + .id_table = pmt_telem_aux_id_table, > + .remove = pmt_telem_remove, > + .probe = pmt_telem_probe, > }; >
