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The piix4 driver can obtain the ASF handle through ACPI to >>>>>>> retrieve information about the ASF controller's attributes, such as the >>>>>>> ASF address space and interrupt number, and to handle ASF interrupts. >>>>>> >>>>>> Can you share an excerpt of DSDT to see how it looks like? >>>>> >>>>> Device (ASFC) >>>>> { >>>>> ... >>>> >>>> Can you put the necessary bits for the enumeration (you may replace some IDs if >>>> they are not public yet to something like XX..XX or xx..xx)? >>> >>> Name (_HID, "AMDIXXXX") // _HID: Hardware ID >>> Name (_UID, Zero) // _UID: Unique ID >> >> Thank you! >> >> Now a question, why your case can't have a separate (platform) device driver? > > I evaluated this approach before proposing the change, considering the > option of creating a separate platform driver, which is relatively > easier to implement. > > However, there are a couple of important points to note: > > - ASF is a subset of SMBus. If a system has 3 SMBus ports, this change > would allow one of the ports to handle ASF operations. > > - In the current i2c_piix4 driver, the assumption is that the port > address 0xb20 is designated for auxiliary operations, but this same > port can also be used for ASF. This could lead to a scenario of port > collision. I tried to highlight this in the commit message, and you > can see some dance in piix4_probe(). > > - As a result, users might encounter an error on platforms that > support ASF: "SMBus region 0x%x already in use!" > > This is why I believe it would be more meaningful to integrate the ASF > changes into the SMBus driver. Andy, I posted a new version. Can you please take a look. This has a separate _HID driver for ASF now with piix4 as library. Thanks, Shyam > > Thoughts..? > > Thanks, > Shyam > >> >>>>> Method (_CRS, 0, NotSerialized) // _CRS: Current Resource Settings >>>>> { >>>>> Name (ASBB, ResourceTemplate () >>>>> { >>>>> Interrupt (ResourceConsumer, Level, ActiveLow, Shared, ,, ) >>>>> { >>>>> 0x00000014, >>>>> } >>>>> IO (Decode16, >>>>> 0x0B20, // Range Minimum >>>>> 0x0B20, // Range Maximum >>>> >>>> Typo in value? Shouldn't this be 0x0b3f? >>> >>> Its is 0xb20, that is meant for ASF. >> >> Yes, I mixed up IO() vs. Memory*() resource. The IO() has two values for >> the start address and you fixed that to the above mentioned value. >> >> TL;DR: this looks okay. >> >>>>> 0x00, // Alignment >>>>> 0x20, // Length >>>>> ) >>>>> Memory32Fixed (ReadWrite, >>>>> 0xFEC00040, // Address Base >>>>> 0x00000100, // Address Length >>>>> ) >>>>> }) >>>>> Return (ASBB) /* \_SB_.ASFC._CRS.ASBB */ >>>>> } >>>>> ... >>>>> } >> >> ... >> >>>>>>> + status = acpi_get_handle(NULL, SB800_ASF_ACPI_PATH, &handle); >>>>>>> + if (ACPI_FAILURE(status)) >>>>>>> + return -ENODEV; >>>>>>> + >>>>>>> + adev = acpi_fetch_acpi_dev(handle); >>>>>>> + if (!adev) >>>>>>> + return -ENODEV; >>>>>> >>>>>> This approach I don't like. I would like to see DSDT for that >>>>>> as I mentioned above. >>>>> >>>>> I have posted the DSDT. Can you please elaborate your remarks? >>>> >>>> Not that parts that affect this... >>> >>> Alright, I have posted the _HID enumeration details above. Please let >>> me know if using acpi_fetch_acpi_dev() is acceptable or if there's a >>> better alternative. >> >>> I am open to making changes based on these clarifications. >> >> Since you have a proper Device object in ACPI, it seems to me that you should >> do other way around, i.e. having a platform device driver for this ACPI device >> (based on _HID) and use piix4 as a library for it. >>