From: Hans de Goede hdegoede@redhat.com
[ Upstream commit 009a789443fe4c8e6b1ecb7c16b4865c026184cd ]
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: 0afa877a5650 ("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 Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/acpi/pmic/intel_pmic.c | 51 +++++++++++++++++++--------------- 1 file changed, 28 insertions(+), 23 deletions(-)
diff --git a/drivers/acpi/pmic/intel_pmic.c b/drivers/acpi/pmic/intel_pmic.c index 452041398b347..36d5a5d50b2ff 100644 --- a/drivers/acpi/pmic/intel_pmic.c +++ b/drivers/acpi/pmic/intel_pmic.c @@ -211,31 +211,36 @@ static acpi_status intel_pmic_regs_handler(u32 function, void *handler_context, void *region_context) { struct intel_pmic_opregion *opregion = region_context; - int result = 0; + int result = -EINVAL; + + if (function == ACPI_WRITE) { + switch (address) { + case 0: + return AE_OK; + case 1: + opregion->ctx.addr |= (*value64 & 0xff) << 8; + return AE_OK; + case 2: + opregion->ctx.addr |= *value64 & 0xff; + return AE_OK; + case 3: + opregion->ctx.val = *value64 & 0xff; + return AE_OK; + case 4: + if (*value64) { + result = regmap_write(opregion->regmap, opregion->ctx.addr, + opregion->ctx.val); + } else { + result = regmap_read(opregion->regmap, opregion->ctx.addr, + &opregion->ctx.val); + } + opregion->ctx.addr = 0; + } + }
- switch (address) { - case 0: - return AE_OK; - case 1: - opregion->ctx.addr |= (*value64 & 0xff) << 8; - return AE_OK; - case 2: - opregion->ctx.addr |= *value64 & 0xff; + if (function == ACPI_READ && address == 3) { + *value64 = opregion->ctx.val; return AE_OK; - case 3: - opregion->ctx.val = *value64 & 0xff; - return AE_OK; - case 4: - if (*value64) { - result = regmap_write(opregion->regmap, opregion->ctx.addr, - opregion->ctx.val); - } else { - result = regmap_read(opregion->regmap, opregion->ctx.addr, - &opregion->ctx.val); - if (result == 0) - *value64 = opregion->ctx.val; - } - memset(&opregion->ctx, 0x00, sizeof(opregion->ctx)); }
if (result < 0) {