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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
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Merge tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-mediagrafted
Pull media updates from Mauro Carvalho Chehab: - v4l2-core: added ISP statistics support and per-block validation - v4l2-core: Allow unknown HDR10 white point and luminance - New camera sensors: Sony IMX678 and IMX471m, Himax HM1092 IR sensor - New codec: Milos: VPU v2.0 codec support - isp driver: gained support for Dreamchip RPPX1 ISP framework - vsp1 driver: gained support for RZ/T2H and RZ/N2H - Novalake driver: gained CVS support for new NVL hardware - dvb-core: fix feed leak on failed DMX_ADD_PID - several driver fixes, cleanups and minor improvements * tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (308 commits) media: ipu-bridge: check all DMI entries when overriding sensor rotation media: v4l2-async: avoid deleting unlinked ASC entry on link error media: rzg2l-cru: Align bytesperline to hardware DMA stride requirement media: intel/ipu6: fix async notifier cleanup leak on parse error media: staging/ipu7: fix async notifier UAF on probe error path media: amd: isp4: fix self-deadlock in isp4sd_pwron_and_init() error path media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem() media: rcar-isp: Fix VSPX reference leaks media: rcar-isp: Release ISPCORE resources media: i2c: imx415: Release runtime PM reference on VBLANK error media: i2c: imx415: Return test pattern write errors media: renesas: vsp1: Declare index variables in for loop statement media: renesas: vsp1: Make reset control optional to support platforms without a reset line media: dt-bindings: media: renesas,vsp1: Document RZ/T2H and RZ/N2H SoCs media: dt-bindings: media: renesas,fcp: Document RZ/T2H and RZ/N2H SoCs media: nxp: imx8-isi: Add additional 32-bit RGB format support media: nxp: imx8-isi: Add 16-bit raw Bayer format support media: nxp: imx8-isi: Implement per-stream reference counting for multiplexed streams media: nxp: imx8-isi: Use BIT_ULL() for 64-bit stream masks media: nxp: imx8-isi: Correct color map between V4L2 and ISI ...
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+.. SPDX-License-Identifier: GPL-2.0
+
+====================
+ACPI CA Debug Output
+====================
+
+The ACPI CA can generate debug output. This document describes how to use this
+facility.
+
+Compile-time configuration
+==========================
+
+The ACPI CA debug output is globally enabled by CONFIG_ACPI_DEBUG. If this
+config option is not set, the debug messages are not even built into the kernel.
+
+Boot- and run-time configuration
+================================
+
+When CONFIG_ACPI_DEBUG=y, you can select the component and level of messages
+you're interested in. At boot-time, use the acpi.debug_layer and
+acpi.debug_level kernel command line options. After boot, you can use the
+debug_layer and debug_level files in /sys/module/acpi/parameters/ to control
+the debug messages.
+
+debug_layer (component)
+=======================
+
+The "debug_layer" is a mask that selects components of interest, e.g., a
+specific part of the ACPI interpreter. To build the debug_layer bitmask, look
+for the "#define _COMPONENT" in an ACPI source file.
+
+You can set the debug_layer mask at boot-time using the acpi.debug_layer
+command line argument, and you can change it after boot by writing values
+to /sys/module/acpi/parameters/debug_layer.
+
+The possible components are defined in include/acpi/acoutput.h.
+
+Reading /sys/module/acpi/parameters/debug_layer shows the supported mask values::
+
+ ACPI_UTILITIES 0x00000001
+ ACPI_HARDWARE 0x00000002
+ ACPI_EVENTS 0x00000004
+ ACPI_TABLES 0x00000008
+ ACPI_NAMESPACE 0x00000010
+ ACPI_PARSER 0x00000020
+ ACPI_DISPATCHER 0x00000040
+ ACPI_EXECUTER 0x00000080
+ ACPI_RESOURCES 0x00000100
+ ACPI_CA_DEBUGGER 0x00000200
+ ACPI_OS_SERVICES 0x00000400
+ ACPI_CA_DISASSEMBLER 0x00000800
+ ACPI_COMPILER 0x00001000
+ ACPI_TOOLS 0x00002000
+
+debug_level
+===========
+
+The "debug_level" is a mask that selects different types of messages, e.g.,
+those related to initialization, method execution, informational messages, etc.
+To build debug_level, look at the level specified in an ACPI_DEBUG_PRINT()
+statement.
+
+The ACPI interpreter uses several different levels, but the Linux
+ACPI core and ACPI drivers generally only use ACPI_LV_INFO.
+
+You can set the debug_level mask at boot-time using the acpi.debug_level
+command line argument, and you can change it after boot by writing values
+to /sys/module/acpi/parameters/debug_level.
+
+The possible levels are defined in include/acpi/acoutput.h. Reading
+/sys/module/acpi/parameters/debug_level shows the supported mask values,
+currently these::
+
+ ACPI_LV_INIT 0x00000001
+ ACPI_LV_DEBUG_OBJECT 0x00000002
+ ACPI_LV_INFO 0x00000004
+ ACPI_LV_INIT_NAMES 0x00000020
+ ACPI_LV_PARSE 0x00000040
+ ACPI_LV_LOAD 0x00000080
+ ACPI_LV_DISPATCH 0x00000100
+ ACPI_LV_EXEC 0x00000200
+ ACPI_LV_NAMES 0x00000400
+ ACPI_LV_OPREGION 0x00000800
+ ACPI_LV_BFIELD 0x00001000
+ ACPI_LV_TABLES 0x00002000
+ ACPI_LV_VALUES 0x00004000
+ ACPI_LV_OBJECTS 0x00008000
+ ACPI_LV_RESOURCES 0x00010000
+ ACPI_LV_USER_REQUESTS 0x00020000
+ ACPI_LV_PACKAGE 0x00040000
+ ACPI_LV_ALLOCATIONS 0x00100000
+ ACPI_LV_FUNCTIONS 0x00200000
+ ACPI_LV_OPTIMIZATIONS 0x00400000
+ ACPI_LV_MUTEX 0x01000000
+ ACPI_LV_THREADS 0x02000000
+ ACPI_LV_IO 0x04000000
+ ACPI_LV_INTERRUPTS 0x08000000
+ ACPI_LV_AML_DISASSEMBLE 0x10000000
+ ACPI_LV_VERBOSE_INFO 0x20000000
+ ACPI_LV_FULL_TABLES 0x40000000
+ ACPI_LV_EVENTS 0x80000000
+
+Examples
+========
+
+For example, drivers/acpi/acpica/evxfevnt.c contains this::
+
+ #define _COMPONENT ACPI_EVENTS
+ ...
+ ACPI_DEBUG_PRINT((ACPI_DB_INIT, "ACPI mode disabled\n"));
+
+To turn on this message, set the ACPI_EVENTS bit in acpi.debug_layer
+and the ACPI_LV_INIT bit in acpi.debug_level. (The ACPI_DEBUG_PRINT
+statement uses ACPI_DB_INIT, which is a macro based on the ACPI_LV_INIT
+definition.)
+
+Enable all AML "Debug" output (stores to the Debug object while interpreting
+AML) during boot::
+
+ acpi.debug_layer=0xffffffff acpi.debug_level=0x2
+
+Enable all ACPI hardware-related messages::
+
+ acpi.debug_layer=0x2 acpi.debug_level=0xffffffff
+
+Enable all ACPI_DB_INFO messages after boot::
+
+ # echo 0x4 > /sys/module/acpi/parameters/debug_level
+
+Show all valid component values::
+
+ # cat /sys/module/acpi/parameters/debug_layer