On Thu, Feb 15, 2018 at 12:19 PM, John Garry <john.garry@xxxxxxxxxx> wrote: >> Nothing apart from only being used by arm64 platforms today, which is >> circumstantial. >> >>> >>> I understand you need to find a place to add the: >>> >>> acpi_indirect_io_scan_init() >>> >>> to be called from core ACPI code because ACPI can't handle probe >>> dependencies in any other way but other than that this patch is >>> a Hisilicon ACPI driver - there is nothing generic in it (or at >>> least there are no standard bindings to make it so). >>> >>> Whether a callback from ACPI core code (acpi_scan_init()) to a driver >>> specific hook is sane or not that's the question and the only reason >>> why you want to add this in drivers/acpi/arm64 rather than, say, >>> drivers/bus (as you do for the DT driver). >>> >>> I do not know Rafael's opinion on the above, I would like to help >>> you make forward progress but please understand my concerns, mostly >>> on FW side. >>> >> >> I did mention an alternative in my "ping" in v12 patch 7/9 (Feb 1), but >> no response to this specific note so I kept on the same path. >> >> Here's what I then wrote: >> "I think another solution - which you may prefer - is to avoid adding >> this scan handler (and all this other scan code) and add a check like >> acpi_is_serial_bus_slave() [which checks the device parent versus a list >> of known indirectIO hosts] to not enumerate these children, and do it >> from the LLDD host probe instead (https://lkml.org/lkml/2017/6/16/250)" >> > > Hi Rafael, Lorenzo, > > I can avoid adding the scan handler in acpi_indirectio.c by skipping the > child enumeration, like with this change in scan.c: > > +static const struct acpi_device_id indirect_io_hosts[] = { > + {"HISI0191", 0}, /* HiSilicon LPC host */ > + {}, > +}; > + > +static bool acpi_is_indirect_io_slave(struct acpi_device *device) > +{ Why don't you put the table definition here? > + struct acpi_device *parent = dev->parent; > + > + if (!parent || acpi_match_device_ids(parent, indirect_io_hosts)) > + return false; > + > + return true; return parent && !acpi_match_device_ids(parent, indirect_io_hosts); > +} > + > static bool acpi_is_serial_bus_slave(struct acpi_device *device) > { > struct list_head resource_list; > bool is_serial_bus_slave = false; > > + if (acpi_is_indirect_io_slave(device)) > + return true; > + > /* Macs use device properties in lieu of _CRS resources */ > > > This means I can move all this scan code into the LLDD. > > What do you think? Please let me know. If Lorenzo agrees, that will be fine by me modulo the above remarks. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
