Commit d72f06ce authored by Andy Shevchenko's avatar Andy Shevchenko Committed by Rafael J. Wysocki
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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: 53c76263 ("serdev: Add ACPI support")
Signed-off-by: default avatarAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent b625fe69

Documentation/firmware-guide/acpi/enumeration.rst

+6 −5
Original line number Diff line number Diff line
@@ -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