Commit Graph

13 Commits

Author SHA1 Message Date
Linus Torvalds 70756b49be It has been a moderately calm cycle for documentation; the significant
changes include:
 
 - Some significant additions to the memory-management documentation
 
 - Some improvements to navigation in the HTML-rendered docs
 
 - More Spanish and Chinese translations
 
 ...and the usual set of typo fixes and such.
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Merge tag 'docs-6.3' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "It has been a moderately calm cycle for documentation; the significant
  changes include:

   - Some significant additions to the memory-management documentation

   - Some improvements to navigation in the HTML-rendered docs

   - More Spanish and Chinese translations

  ... and the usual set of typo fixes and such"

* tag 'docs-6.3' of git://git.lwn.net/linux: (68 commits)
  Documentation/watchdog/hpwdt: Fix Format
  Documentation/watchdog/hpwdt: Fix Reference
  Documentation: core-api: padata: correct spelling
  docs/mm: Physical Memory: correct spelling in reference to CONFIG_PAGE_EXTENSION
  docs: Use HTML comments for the kernel-toc SPDX line
  docs: Add more information to the HTML sidebar
  Documentation: KVM: Update AMD memory encryption link
  printk: Document that CONFIG_BOOT_PRINTK_DELAY required for boot_delay=
  Documentation: userspace-api: correct spelling
  Documentation: sparc: correct spelling
  Documentation: driver-api: correct spelling
  Documentation: admin-guide: correct spelling
  docs: add workload-tracing document to admin-guide
  docs/admin-guide/mm: remove useless markup
  docs/mm: remove useless markup
  docs/mm: Physical Memory: remove useless markup
  docs/sp_SP: Add process magic-number translation
  docs: ftrace: always use canonical ftrace path
  Doc/damon: fix the data path error
  dma-buf: Add "dma-buf" to title of documentation
  ...
2023-02-22 12:00:20 -08:00
Maximilian Luz b09ee1cd59 platform/surface: aggregator: Rename top-level request functions to avoid ambiguities
We currently have a struct ssam_request_sync and a function
ssam_request_sync(). While this is valid C, there are some downsides to
it.

One of these is that current Sphinx versions (>= 3.0) cannot
disambiguate between the two (see disucssion and pull request linked
below). It instead emits a "WARNING: Duplicate C declaration" and links
for the struct and function in the resulting documentation link to the
same entry (i.e. both to either function or struct documentation)
instead of their respective own entries.

While we could just ignore that and wait for a fix, there's also a point
to be made that the current naming can be somewhat confusing when
searching (e.g. via grep) or trying to understand the levels of
abstraction at play:

We currently have struct ssam_request_sync and associated functions
ssam_request_sync_[alloc|free|init|wait|...]() operating on this struct.
However, function ssam_request_sync() is one abstraction level above
this. Similarly, ssam_request_sync_with_buffer() is not a function
operating on struct ssam_request_sync, but rather a sibling to
ssam_request_sync(), both using the struct under the hood.

Therefore, rename the top level request functions:

  ssam_request_sync() -> ssam_request_do_sync()
  ssam_request_sync_with_buffer() -> ssam_request_do_sync_with_buffer()
  ssam_request_sync_onstack() -> ssam_request_do_sync_onstack()

Link: https://lore.kernel.org/all/085e0ada65c11da9303d07e70c510dc45f21315b.1656756450.git.mchehab@kernel.org/
Link: https://github.com/sphinx-doc/sphinx/pull/8313
Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20221220175608.1436273-2-luzmaximilian@gmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2023-02-02 22:48:20 +01:00
Maximilian Luz 3f88b459a7 platform/surface: aggregator: Improve documentation and handling of message target and source IDs
The `tid_in` and `tid_out` fields of the serial hub protocol command
struct (struct ssh_command) are actually source and target IDs,
indicating the peer from which the message originated and the peer for
which it is intended.

Change the naming of those fields accordingly and improve the protocol
documentation. Additionally, introduce an enum containing all currently
known peers, i.e. targets and sources.

Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20221202223327.690880-3-luzmaximilian@gmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2023-02-02 22:48:20 +01:00
Randy Dunlap 7852fe3a09 Documentation: driver-api: correct spelling
Correct spelling problems for Documentation/driver-api/ as reported
by codespell.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: linux-media@vger.kernel.org
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: nvdimm@lists.linux.dev
Cc: Vinod Koul <vkoul@kernel.org>
Cc: dmaengine@vger.kernel.org
Cc: linux-raid@vger.kernel.org
Cc: linux-usb@vger.kernel.org
Acked-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Song Liu <song@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20230129231053.20863-3-rdunlap@infradead.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2023-02-02 11:05:16 -07:00
Maximilian Luz 5c1e88b98c platform/surface: aggregator: Allow notifiers to avoid communication on unregistering
When SSAM client devices have been (physically) hot-removed,
communication attempts with those devices may fail and time out. This
can even extend to event notifiers, due to which timeouts may occur
during device removal, slowing down that process.

Add a parameter to the notifier unregister function that allows skipping
communication with the EC to prevent this. Furthermore, add wrappers for
registering and unregistering notifiers belonging to SSAM client devices
that automatically check if the device has been marked as hot-removed
and communication should be avoided.

Note that non-SSAM client devices can generally not be hot-removed, so
also add a convenience wrapper for those, defaulting to allow
communication.

Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20220527023447.2460025-4-luzmaximilian@gmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2022-06-13 17:25:07 +02:00
Linus Torvalds 776ba3ad65 platform-drivers-x86 for v5.14-1
Highlights:
  - New think-lmi driver adding support for changing BIOS settings from
    within Linux using the standard firmware-attributes class sysfs API
  - MS Surface aggregator-cdev now also supports forwarding events to
    user-space (for debugging / new driver development purposes only)
  - New intel_skl_int3472 driver this provides the necessary glue to
    translate ACPI table information to GPIOs, regulators, etc. for
    camera sensors on Intel devices with IPU3 attached MIPI cameras
  - A whole bunch of other fixes + device-specific quirk additions
  - New devm_work_autocancel() devm-helpers.h function
 
 Note this also contains merges of the following immutable branches/tags
 shared with other subsystems:
  - platform-drivers-x86-goodix-v5.14-1
  - intel-gpio-v5.14-1
  - linux-pm/acpi-scan
  - devm-helpers-v5.14-1
 
 The following is an automated git shortlog grouped by driver:
 
 ACPI:
  -  scan: initialize local variable to avoid garbage being returned
  -  scan: Add function to fetch dependent of ACPI device
  -  scan: Extend acpi_walk_dep_device_list()
  -  scan: Rearrange dep_unmet initialization
 
 Add intel_skl_int3472 driver:
  - Add intel_skl_int3472 driver
 
 ISST:
  -  Use numa node id for cpu pci dev mapping
  -  Optimize CPU to PCI device mapping
 
 Input:
  -  goodix - platform/x86: touchscreen_dmi - Move upside down quirks to touchscreen_dmi.c
 
 MAINTAINERS:
  -  Update IRC link for Surface System Aggregator subsystem
  -  Update info for telemetry
 
 Merge remote-tracking branch 'linux-pm/acpi-scan' into review-hans:
  - Merge remote-tracking branch 'linux-pm/acpi-scan' into review-hans
 
 Merge tag 'devm-helpers-v5.14-1' into review-hans:
  - Merge tag 'devm-helpers-v5.14-1' into review-hans
 
 Merge tag 'intel-gpio-v5.14-1' into review-hans:
  - Merge tag 'intel-gpio-v5.14-1' into review-hans
 
 Merge tag 'platform-drivers-x86-goodix-v5.14-1' into review-hans:
  - Merge tag 'platform-drivers-x86-goodix-v5.14-1' into review-hans
 
 Remove "default n" entries:
  - Remove "default n" entries
 
 Rename hp-wireless to wireless-hotkey:
  - Rename hp-wireless to wireless-hotkey
 
 asus-nb-wmi:
  -  Revert "add support for ASUS ROG Zephyrus G14 and G15"
  -  Revert "Drop duplicate DMI quirk structures"
 
 dcdbas:
  -  drop unneeded assignment in host_control_smi()
 
 dell-privacy:
  -  Add support for Dell hardware privacy
 
 dell-wmi:
  -  Rename dell-wmi.c to dell-wmi-base.c
 
 dell-wmi-sysman:
  -  Change user experience when Admin/System Password is modified
  -  fw_attr_inuse can be static
  -  Use firmware_attributes_class helper
  -  Make populate_foo_data functions more robust
 
 dell-wmi-sysman/think-lmi:
  -  Make fw_attr_class global static
 
 devm-helpers:
  -  Add resource managed version of work init
 
 docs:
  -  driver-api: Update Surface Aggregator user-space interface documentation
 
 extcon:
  -  extcon-max8997: Simplify driver using devm
  -  extcon-max8997: Fix IRQ freeing at error path
  -  extcon-max77693.c: Fix potential work-queue cancellation race
  -  extcon-max14577: Fix potential work-queue cancellation race
 
 firmware_attributes_class:
  -  Create helper file for handling firmware-attributes class registration events
 
 gpio:
  -  wcove: Split error handling for CTRL and IRQ registers
  -  wcove: Unify style of to_reg() with to_ireg()
  -  wcove: Use IRQ hardware number getter instead of direct access
  -  crystalcove: remove platform_set_drvdata() + cleanup probe
 
 gpiolib:
  -  acpi: Add acpi_gpio_get_io_resource()
  -  acpi: Introduce acpi_get_and_request_gpiod() helper
 
 hdaps:
  -  Constify static attribute_group struct
 
 ideapad-laptop:
  -  Ignore VPC event bit 10
 
 intel_cht_int33fe:
  -  Move to its own subfolder
  -  Correct "displayport" fwnode reference
 
 intel_ips:
  -  fix set but unused warning in read_mgtv
 
 intel_pmt_crashlog:
  -  Constify static attribute_group struct
 
 intel_skl_int3472:
  -  Uninitialized variable in skl_int3472_handle_gpio_resources()
  -  Move to intel/ subfolder
  -  Provide skl_int3472_unregister_clock()
  -  Provide skl_int3472_unregister_regulator()
  -  Use ACPI GPIO resource directly
  -  Fix dependencies (drop CLKDEV_LOOKUP)
  -  Free ACPI device resources after use
 
 mfd:
  -  tps68470: Remove tps68470 MFD driver
 
 platform/mellanox:
  -  mlxreg-hotplug: Revert "move to use request_irq by IRQF_NO_AUTOEN flag"
 
 platform/surface:
  -  aggregator: Use list_move_tail instead of list_del/list_add_tail in ssh_packet_layer.c
  -  aggregator: Use list_move_tail instead of list_del/list_add_tail in ssh_request_layer.c
  -  aggregator: Drop unnecessary variable initialization
  -  aggregator: Do not return uninitialized value
  -  aggregator_cdev: Add lockdep support
  -  aggregator_cdev: Allow enabling of events from user-space
  -  aggregator_cdev: Add support for forwarding events to user-space
  -  aggregator: Update copyright
  -  aggregator: Allow enabling of events without notifiers
  -  aggregator: Allow registering notifiers without enabling events
  -  dtx: Add missing mutex_destroy() call in failure path
  -  aggregator: Fix event disable function
  -  aggregator_registry: Consolidate node groups for 5th- and 6th-gen devices
  -  aggregator_registry: Add support for 13" Intel Surface Laptop 4
  -  aggregator_registry: Update comments for 15" AMD Surface Laptop 4
 
 samsung-laptop:
  -  set debugfs blobs to read only
  -  use octal numbers for rwx file permissions
 
 tc1100-wmi:
  -  Constify static attribute_group struct
 
 think-lmi:
  -  Move kfree(setting->possible_values) to tlmi_attr_setting_release()
  -  Split current_value to reflect only the value
  -  Fix issues with duplicate attributes
  -  Return EINVAL when kbdlang gets set to a 0 length string
  -  Add missing MODULE_DEVICE_TABLE
  -  Avoid potential read before start of the buffer
  -  Fix check for admin password being set
  -  Add WMI interface support on Lenovo platforms
 
 thinkpad-lmi:
  -  Remove unused display_name member from struct tlmi_pwd_setting
 
 thinkpad_acpi:
  -  Add X1 Carbon Gen 9 second fan support
  -  Fix inconsistent indenting
 
 tools/power/x86/intel-speed-select:
  -  v1.10 release
  -  Fix uncore memory frequency display
 
 toshiba_acpi:
  -  Fix missing error code in toshiba_acpi_setup_keyboard()
 
 toshiba_haps:
  -  Fix missing newline in pr_debug call in toshiba_haps_notify
 
 touchscreen_dmi:
  -  Fix Chuwi Hi10 Pro comment
  -  Add info for the Goodix GT912 panel of TM800A550L tablets
  -  Add an extra entry for the upside down Goodix touchscreen on Teclast X89 tablets
 
 x86/platform/uv:
  -  Constify static attribute_group struct
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Merge tag 'platform-drivers-x86-v5.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86

Pull x86 platform driver updates from Hans de Goede:
 "Highlights:

   - New think-lmi driver adding support for changing Lenovo Thinkpad
     BIOS settings from within Linux using the standard firmware-
     attributes class sysfs API

   - MS Surface aggregator-cdev now also supports forwarding events to
     user-space (for debugging / new driver development purposes only)

   - New intel_skl_int3472 driver this provides the necessary glue to
     translate ACPI table information to GPIOs, regulators, etc. for
     camera sensors on Intel devices with IPU3 attached MIPI cameras

   - A whole bunch of other fixes + device-specific quirk additions

   - New devm_work_autocancel() devm-helpers.h function"

* tag 'platform-drivers-x86-v5.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86: (83 commits)
  platform/x86: dell-wmi-sysman: Change user experience when Admin/System Password is modified
  platform/x86: intel_skl_int3472: Uninitialized variable in skl_int3472_handle_gpio_resources()
  platform/x86: think-lmi: Move kfree(setting->possible_values) to tlmi_attr_setting_release()
  platform/x86: think-lmi: Split current_value to reflect only the value
  platform/x86: think-lmi: Fix issues with duplicate attributes
  platform/x86: think-lmi: Return EINVAL when kbdlang gets set to a 0 length string
  platform/x86: intel_cht_int33fe: Move to its own subfolder
  platform/x86: intel_skl_int3472: Move to intel/ subfolder
  platform/x86: intel_skl_int3472: Provide skl_int3472_unregister_clock()
  platform/x86: intel_skl_int3472: Provide skl_int3472_unregister_regulator()
  platform/x86: intel_skl_int3472: Use ACPI GPIO resource directly
  platform/x86: intel_skl_int3472: Fix dependencies (drop CLKDEV_LOOKUP)
  platform/x86: intel_skl_int3472: Free ACPI device resources after use
  platform/x86: Remove "default n" entries
  platform/x86: ISST: Use numa node id for cpu pci dev mapping
  platform/x86: ISST: Optimize CPU to PCI device mapping
  tools/power/x86/intel-speed-select: v1.10 release
  tools/power/x86/intel-speed-select: Fix uncore memory frequency display
  extcon: extcon-max8997: Simplify driver using devm
  extcon: extcon-max8997: Fix IRQ freeing at error path
  ...
2021-06-30 11:15:39 -07:00
Mauro Carvalho Chehab bbbaf2264d docs: driver-api: surface_aggregator: avoid using ReST :doc:`foo` markup
The :doc:`foo` tag is auto-generated via automarkup.py.
So, use the filename at the sources, instead of :doc:`foo`.

Acked-by: Maximilian Luz <luzmaximilian@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/6097027b4de4c9015485cb73b297b98660c4296d.1623824363.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-06-17 13:24:38 -06:00
Maximilian Luz 8ae200547a docs: driver-api: Update Surface Aggregator user-space interface documentation
Update the controller-device user-space interface (cdev) documentation
for the newly introduced IOCTLs and event interface.

Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20210604134755.535590-8-luzmaximilian@gmail.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2021-06-16 17:47:53 +02:00
Maximilian Luz f614a1e23a docs: driver-api: Add Surface DTX driver documentation
Add documentation for the user-space interface of the Surface DTX
(detachment system) driver, used on Microsoft Surface Book series
devices.

Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20210308184819.437438-4-luzmaximilian@gmail.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2021-03-17 18:39:39 +01:00
Maximilian Luz 03ee318391 platform/surface: aggregator: Make SSAM_DEFINE_SYNC_REQUEST_x define static functions
The SSAM_DEFINE_SYNC_REQUEST_x() macros are intended to reduce
boiler-plate code for SSAM request definitions by defining a wrapper
function for the specified request. The client device variants of those
macros, i.e. SSAM_DEFINE_SYNC_REQUEST_CL_x() in particular rely on the
multi-device (MD) variants, e.g.:

    #define SSAM_DEFINE_SYNC_REQUEST_CL_R(name, rtype, spec...)   \
        SSAM_DEFINE_SYNC_REQUEST_MD_R(__raw_##name, rtype, spec)  \
        int name(struct ssam_device *sdev, rtype *ret)            \
        {                                                         \
            return __raw_##name(sdev->ctrl, sdev->uid.target,     \
                                sdev->uid.instance, ret);         \
        }

This now creates the problem that it is not possible to declare the
generated functions static via

    static SSAM_DEFINE_SYNC_REQUEST_CL_R(...)

as this will only apply to the function defined by the multi-device
macro, i.e. SSAM_DEFINE_SYNC_REQUEST_MD_R(). Thus compiling with
`-Wmissing-prototypes' rightfully complains that there is a 'static'
keyword missing.

To solve this, make all SSAM_DEFINE_SYNC_REQUEST_x() macros define
static functions. Non-client-device macros are also changed for
consistency. In general, we expect those functions to be only used
locally in the respective drivers for the corresponding interfaces, so
having to define a wrapper function to be able to export this should be
the odd case out.

Reported-by: kernel test robot <lkp@intel.com>
Fixes: b78b4982d7 ("platform/surface: Add platform profile driver")
Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20210304190524.1172197-1-luzmaximilian@gmail.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2021-03-08 11:33:28 +01:00
Maximilian Luz fc00bc8ac1 platform/surface: Add Surface ACPI Notify driver
The Surface ACPI Notify (SAN) device provides an ACPI interface to the
Surface Aggregator EC, specifically the Surface Serial Hub interface.
This interface allows EC requests to be made from ACPI code and can
convert a subset of EC events back to ACPI notifications.

Specifically, this interface provides a GenericSerialBus operation
region ACPI code can execute a request by writing the request command
data and payload to this operation region and reading back the
corresponding response via a write-then-read operation. Furthermore,
this interface provides a _DSM method to be called when certain events
from the EC have been received, essentially turning them into ACPI
notifications.

The driver provided in this commit essentially takes care of translating
the request data written to the operation region, executing the request,
waiting for it to finish, and finally writing and translating back the
response (if the request has one). Furthermore, this driver takes care
of enabling the events handled via ACPI _DSM calls. Lastly, this driver
also exposes an interface providing discrete GPU (dGPU) power-on
notifications on the Surface Book 2, which are also received via the
operation region interface (but not handled by the SAN driver directly),
making them accessible to other drivers (such as a dGPU hot-plug driver
that may be added later on).

On 5th and 6th generation Surface devices (Surface Pro 5/2017, Pro 6,
Book 2, Laptop 1 and 2), the SAN interface provides full battery and
thermal subsystem access, as well as other EC based functionality. On
those models, battery and thermal sensor devices are implemented as
standard ACPI devices of that type, however, forward ACPI calls to the
corresponding Surface Aggregator EC request via the SAN interface and
receive corresponding notifications (e.g. battery information change)
from it. This interface is therefore required to provide said
functionality on those devices.

Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20201221183959.1186143-10-luzmaximilian@gmail.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2021-01-07 00:06:39 +01:00
Maximilian Luz 178f6ab77e platform/surface: Add Surface Aggregator user-space interface
Add a misc-device providing user-space access to the Surface Aggregator
EC, mainly intended for debugging, testing, and reverse-engineering.
This interface gives user-space applications the ability to send
requests to the EC and receive the corresponding responses.

The device-file is managed by a pseudo platform-device and corresponding
driver to avoid dependence on the dedicated bus, allowing it to be
loaded in a minimal configuration.

A python library and scripts to access this device can be found at [1].

[1]: https://github.com/linux-surface/surface-aggregator-module/tree/master/scripts/ssam

Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20201221183959.1186143-9-luzmaximilian@gmail.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2021-01-07 00:06:39 +01:00
Maximilian Luz 8d7792823d docs: driver-api: Add Surface Aggregator subsystem documentation
Add documentation for the Surface Aggregator subsystem and its client
drivers, giving an overview of the subsystem, its use-cases, its
internal structure and internal API, as well as its external API for
writing client drivers.

Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20201221183959.1186143-8-luzmaximilian@gmail.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2021-01-07 00:06:39 +01:00