009a789443
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:
|
||
|---|---|---|
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.