kernel/linux.git/Documentation/firmware-guide, branch v5.10.257

Documentation: ACPI: Fix parent device references

2025-08-28T14:22:39+00:00

commit e65cb011349e653ded541dddd6469c2ca813edcf upstream. The _CRS resources in many cases want to have ResourceSource field to be a type of ACPI String. This means that to compile properly we need to enclosure the name path into double quotes. This will in practice defer the interpretation to a run-time stage, However, this may be interpreted differently on different OSes and ACPI interpreter implementations. In particular ACPICA might not correctly recognize the leading '^' (caret) character and will not resolve the relative name path properly. On top of that, this piece may be used in SSDTs which are loaded after the DSDT and on itself may also not resolve relative name paths outside of their own scopes. With this all said, fix documentation to use fully-qualified name paths always to avoid any misinterpretations, which is proven to work. Fixes: 8eb5c87a92c0 ("i2c: add ACPI support for I2C mux ports") Reported-by: Yevhen Kondrashyn Cc: All applicable Signed-off-by: Andy Shevchenko Link: https://patch.msgid.link/20250710170225.961303-1-andriy.shevchenko@linux.intel.com Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

Documentation: ACPI: EINJ: Fix obsolete example

2022-08-25T09:37:53+00:00

commit 9066e151c37950af92c3be6a7270daa8e8063db9 upstream. Since commit 488dac0c9237 ("libfs: fix error cast of negative value in simple_attr_write()"), the EINJ debugfs interface no longer accepts negative values as input. Attempt to do so will result in EINVAL. Fixes: 488dac0c9237 ("libfs: fix error cast of negative value in simple_attr_write()") Signed-off-by: Qifu Zhang Reviewed-by: Tony Luck Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

Documentation: ACPI: Fix data node reference documentation

2022-01-27T09:54:29+00:00

commit a11174952205d082f1658fab4314f0caf706e0a8 upstream. The data node reference documentation was missing a package that must contain the property values, instead property name and multiple values being present in a single package. This is not aligned with the _DSD spec. Fix it by adding the package for the values. Also add the missing "reg" properties to two numbered nodes. Fixes: b10134a3643d ("ACPI: property: Document hierarchical data extension references") Signed-off-by: Sakari Ailus Reviewed-by: Andy Shevchenko Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

Documentation: ACPI: fix spelling mistakes

2020-11-10T17:48:56+00:00

Signed-off-by: Flavio Suligoi Signed-off-by: Rafael J. Wysocki

Documentation: firmware-guide: gpio-properties: Clarify initial output state

2020-11-09T17:59:43+00:00

GpioIo() doesn't provide an explicit state for an output pin. Linux tries to be smart and uses a common sense based on other parameters. Document how it looks like in the code. Signed-off-by: Andy Shevchenko Reviewed-by: Mika Westerberg Signed-off-by: Rafael J. Wysocki

Documentation: firmware-guide: gpio-properties: active_low only for GpioIo()

2020-11-09T17:59:43+00:00

It appears that people may misinterpret active_low field in _DSD for GpioInt() resource. Add a paragraph to clarify this. Reported-by: Ricardo Ribalda Signed-off-by: Andy Shevchenko Reviewed-by: Mika Westerberg Reviewed-by: Ricardo Ribalda Signed-off-by: Rafael J. Wysocki

Documentation: firmware-guide: gpio-properties: Fix factual mistakes

2020-11-09T17:59:42+00:00

Fix factual mistakes and style issues in GPIO properties document. This converts IoRestriction from InputOnly to OutputOnly as pins in the example are used as outputs. Signed-off-by: Andy Shevchenko Signed-off-by: Rafael J. Wysocki

docs: add some new files to their respective index.rst files

2020-09-10T16:48:20+00:00

There were some new file additions for Kernel 5.7 and 5.8 that weren't added at the corresponding index file. Signed-off-by: Mauro Carvalho Chehab Link: https://lore.kernel.org/r/9fd4d04f0d122ff38b5342a0098d99cc2f546652.1599660067.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet

ACPI: Replace HTTP links with HTTPS ones

2020-07-27T12:47:08+00:00

Rationale: Reduces attack surface on kernel devs opening the links for MITM as HTTPS traffic is much harder to manipulate. Deterministic algorithm: For each file: If not .svg: For each line: If doesn't contain `\bxmlns\b`: For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`: If neither `\bgnu\.org/license`, nor `\bmozilla\.org/MPL\b`: If both the HTTP and HTTPS versions return 200 OK and serve the same content: Replace HTTP with HTTPS. Signed-off-by: Alexander A. Klimov Acked-by: Vishal Verma Acked-by: Sakari Ailus Signed-off-by: Rafael J. Wysocki

usb: typec: Add firmware documentation for the Intel PMC mux control

2020-05-13T12:20:49+00:00

Adding documentation that describes how the PMC mux-agent function is described in the ACPI tables. Signed-off-by: Heikki Krogerus Link: https://lore.kernel.org/r/20200507150900.12102-4-heikki.krogerus@linux.intel.com Signed-off-by: Greg Kroah-Hartman