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authorAndy Shevchenko <andriy.shevchenko@linux.intel.com>2022-02-28 23:39:31 +0100
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2022-03-03 20:34:45 +0100
commitd72f06cee0d5cad0056967f0edc2c23b984238ba (patch)
tree620622a3645031df87866240a7f8b22de842a2f7 /Documentation/firmware-guide/acpi
parentACPI: docs: enumeration: Discourage to use custom _DSM methods (diff)
downloadlinux-d72f06cee0d5cad0056967f0edc2c23b984238ba.tar.xz
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ACPI: docs: enumeration: Update UART serial bus resource documentation
In some cases UART serial bus resource may be represented by struct serdev_device. Fixes: 53c7626356c7 ("serdev: Add ACPI support") Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'Documentation/firmware-guide/acpi')
-rw-r--r--Documentation/firmware-guide/acpi/enumeration.rst11
1 files changed, 6 insertions, 5 deletions
diff --git a/Documentation/firmware-guide/acpi/enumeration.rst b/Documentation/firmware-guide/acpi/enumeration.rst
index cda41e4255eb..799ca240e612 100644
--- a/Documentation/firmware-guide/acpi/enumeration.rst
+++ b/Documentation/firmware-guide/acpi/enumeration.rst
@@ -19,16 +19,17 @@ possible we decided to do following:
platform devices.
- Devices behind real busses where there is a connector resource
- are represented as struct spi_device or struct i2c_device
- (standard UARTs are not busses so there is no struct uart_device).
+ are represented as struct spi_device or struct i2c_device. Note
+ that standard UARTs are not busses so there is no struct uart_device,
+ although some of them may be represented by sturct serdev_device.
As both ACPI and Device Tree represent a tree of devices (and their
resources) this implementation follows the Device Tree way as much as
possible.
-The ACPI implementation enumerates devices behind busses (platform, SPI and
-I2C), creates the physical devices and binds them to their ACPI handle in
-the ACPI namespace.
+The ACPI implementation enumerates devices behind busses (platform, SPI,
+I2C, and in some cases UART), creates the physical devices and binds them
+to their ACPI handle in the ACPI namespace.
This means that when ACPI_HANDLE(dev) returns non-NULL the device was
enumerated from ACPI namespace. This handle can be used to extract other