ACPI: PMIC: Fix intel_pmic_regs_handler() read accesses
The handling of PMIC register reads through writing 0 to address 4 of the OpRegion is wrong. Instead of returning the read value through the value64, which is a no-op for function == ACPI_WRITE calls, store the value and then on a subsequent function == ACPI_READ with address == 3 (the address for the value field of the OpRegion) return the stored value. This has been tested on a Xiaomi Mi Pad 2 and makes the ACPI battery dev there mostly functional (unfortunately there are still other issues). Here are the SET() / GET() functions of the PMIC ACPI device, which use this OpRegion, which clearly show the new behavior to be correct: OperationRegion (REGS, 0x8F, Zero, 0x50) Field (REGS, ByteAcc, NoLock, Preserve) { CLNT, 8, SA, 8, OFF, 8, VAL, 8, RWM, 8 } Method (GET, 3, Serialized) { If ((AVBE == One)) { CLNT = Arg0 SA = Arg1 OFF = Arg2 RWM = Zero If ((AVBG == One)) { GPRW = Zero } } Return (VAL) /* \_SB_.PCI0.I2C7.PMI5.VAL_ */ } Method (SET, 4, Serialized) { If ((AVBE == One)) { CLNT = Arg0 SA = Arg1 OFF = Arg2 VAL = Arg3 RWM = One If ((AVBG == One)) { GPRW = One } } } Fixes: 0afa877a ("ACPI / PMIC: intel: add REGS operation region support") Signed-off-by:Hans de Goede <hdegoede@redhat.com> Signed-off-by:
Rafael J. Wysocki <rafael.j.wysocki@intel.com>
parent
c0d6586a
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