diff options
| author | Changbin Du <changbin.du@gmail.com> | 2019-04-24 19:52:54 +0200 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2019-04-25 23:07:20 +0200 |
| commit | 572c9fa516f532d6cfd7123d7753fe52730f1c59 (patch) | |
| tree | 905366cf7b7dfc5b643cb272f1aaf621de4e5fa4 /Documentation/firmware-guide/acpi/i2c-muxes.rst | |
| parent | Documentation: ACPI: move dsdt-override.txt to admin-guide/acpi and convert t... (diff) | |
| download | linux-572c9fa516f532d6cfd7123d7753fe52730f1c59.tar.xz linux-572c9fa516f532d6cfd7123d7753fe52730f1c59.zip | |
Documentation: ACPI: move i2c-muxes.txt to firmware-guide/acpi and convert to reST
This converts the plain text documentation to reStructuredText format
and adds it to Sphinx TOC tree.
No essential content change.
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'Documentation/firmware-guide/acpi/i2c-muxes.rst')
| -rw-r--r-- | Documentation/firmware-guide/acpi/i2c-muxes.rst | 61 |
1 files changed, 61 insertions, 0 deletions
diff --git a/Documentation/firmware-guide/acpi/i2c-muxes.rst b/Documentation/firmware-guide/acpi/i2c-muxes.rst new file mode 100644 index 000000000000..3a8997ccd7c4 --- /dev/null +++ b/Documentation/firmware-guide/acpi/i2c-muxes.rst @@ -0,0 +1,61 @@ +.. SPDX-License-Identifier: GPL-2.0 + +============== +ACPI I2C Muxes +============== + +Describing an I2C device hierarchy that includes I2C muxes requires an ACPI +Device () scope per mux channel. + +Consider this topology:: + + +------+ +------+ + | SMB1 |-->| MUX0 |--CH00--> i2c client A (0x50) + | | | 0x70 |--CH01--> i2c client B (0x50) + +------+ +------+ + +which corresponds to the following ASL:: + + Device (SMB1) + { + Name (_HID, ...) + Device (MUX0) + { + Name (_HID, ...) + Name (_CRS, ResourceTemplate () { + I2cSerialBus (0x70, ControllerInitiated, I2C_SPEED, + AddressingMode7Bit, "^SMB1", 0x00, + ResourceConsumer,,) + } + + Device (CH00) + { + Name (_ADR, 0) + + Device (CLIA) + { + Name (_HID, ...) + Name (_CRS, ResourceTemplate () { + I2cSerialBus (0x50, ControllerInitiated, I2C_SPEED, + AddressingMode7Bit, "^CH00", 0x00, + ResourceConsumer,,) + } + } + } + + Device (CH01) + { + Name (_ADR, 1) + + Device (CLIB) + { + Name (_HID, ...) + Name (_CRS, ResourceTemplate () { + I2cSerialBus (0x50, ControllerInitiated, I2C_SPEED, + AddressingMode7Bit, "^CH01", 0x00, + ResourceConsumer,,) + } + } + } + } + } |