From d72f06cee0d5cad0056967f0edc2c23b984238ba Mon Sep 17 00:00:00 2001
From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Date: Tue, 1 Mar 2022 00:39:31 +0200
Subject: [PATCH] ACPI: docs: enumeration: Update UART serial bus resource documentation
Git-commit: d72f06cee0d5cad0056967f0edc2c23b984238ba
Patch-mainline: v5.18-rc1
References: git-fixes
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>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
Documentation/firmware-guide/acpi/enumeration.rst | 11 ++++++-----
1 file 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
--
2.31.1