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2025-10-06Merge tag 'pci-v6.18-changes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci Pull pci updates from Bjorn Helgaas: "Enumeration: - Add PCI_FIND_NEXT_CAP() and PCI_FIND_NEXT_EXT_CAP() macros that take config space accessor functions. Implement pci_find_capability(), pci_find_ext_capability(), and dwc, dwc endpoint, and cadence capability search interfaces with them (Hans Zhang) - Leave parent unit address 0 in 'interrupt-map' so that when we build devicetree nodes to describe PCI functions that contain multiple peripherals, we can build this property even when interrupt controllers lack 'reg' properties (Lorenzo Pieralisi) - Add a Xeon 6 quirk to disable Extended Tags and limit Max Read Request Size to 128B to avoid a performance issue (Ilpo Järvinen) - Add sysfs 'serial_number' file to expose the Device Serial Number (Matthew Wood) - Fix pci_acpi_preserve_config() memory leak (Nirmoy Das) Resource management: - Align m68k pcibios_enable_device() with other arches (Ilpo Järvinen) - Remove sparc pcibios_enable_device() implementations that don't do anything beyond what pci_enable_resources() does (Ilpo Järvinen) - Remove mips pcibios_enable_resources() and use pci_enable_resources() instead (Ilpo Järvinen) - Clean up bridge window sizing and assignment (Ilpo Järvinen), including: - Leave non-claimed bridge windows disabled - Enable bridges even if a window wasn't assigned because not all windows are required by downstream devices - Preserve bridge window type when releasing the resource, since the type is needed for reassignment - Consolidate selection of bridge windows into two new interfaces, pbus_select_window() and pbus_select_window_for_type(), so this is done consistently - Compute bridge window start and end earlier to avoid logging stale information MSI: - Add quirk to disable MSI on RDC PCI to PCIe bridges (Marcos Del Sol Vives) Error handling: - Align AER with EEH by allowing drivers to request a Bus Reset on Non-Fatal Errors (in addition to the reset on Fatal Errors that we already do) (Lukas Wunner) - If error recovery fails, emit FAILED_RECOVERY uevents for the devices, not for the bridge leading to them. This makes them correspond to BEGIN_RECOVERY uevents (Lukas Wunner) - Align AER with EEH by calling err_handler.error_detected() callbacks to notify drivers if error recovery fails (Lukas Wunner) - Align AER with EEH by restoring device error_state to pci_channel_io_normal before the err_handler.slot_reset() callback. This is earlier than before the err_handler.resume() callback (Lukas Wunner) - Emit a BEGIN_RECOVERY uevent when driver's err_handler.error_detected() requests a reset, as well as when it says recovery is complete or can be done without a reset (Niklas Schnelle) - Align s390 with AER and EEH by emitting uevents during error recovery (Niklas Schnelle) - Align EEH with AER and s390 by emitting BEGIN_RECOVERY, SUCCESSFUL_RECOVERY, or FAILED_RECOVERY uevents depending on the result of err_handler.error_detected() (Niklas Schnelle) - Fix a NULL pointer dereference in aer_ratelimit() when ACPI GHES error information identifies a device without an AER Capability (Breno Leitao) - Update error decoding and TLP Log printing for new errors in current PCIe base spec (Lukas Wunner) - Update error recovery documentation to match the current code and use consistent nomenclature (Lukas Wunner) ASPM: - Enable all ClockPM and ASPM states for devicetree platforms, since there's typically no firmware that enables ASPM This is a risky change that may uncover hardware or configuration defects at boot-time rather than when users enable ASPM via sysfs later. Booting with "pcie_aspm=off" prevents this enabling (Manivannan Sadhasivam) - Remove the qcom code that enabled ASPM (Manivannan Sadhasivam) Power management: - If a device has already been disconnected, e.g., by a hotplug removal, don't bother trying to resume it to D0 when detaching the driver. This avoids annoying "Unable to change power state from D3cold to D0" messages (Mario Limonciello) - Ensure devices are powered up before config reads for 'max_link_width', 'current_link_speed', 'current_link_width', 'secondary_bus_number', and 'subordinate_bus_number' sysfs files. This prevents using invalid data (~0) in drivers or lspci and, depending on how the PCIe controller reports errors, may avoid error interrupts or crashes (Brian Norris) Virtualization: - Add rescan/remove locking when enabling/disabling SR-IOV, which avoids list corruption on s390, where disabling SR-IOV also generates hotplug events (Niklas Schnelle) Peer-to-peer DMA: - Free struct p2p_pgmap, not a member within it, in the pci_p2pdma_add_resource() error path (Sungho Kim) Endpoint framework: - Document sysfs interface for BAR assignment of vNTB endpoint functions (Jerome Brunet) - Fix array underflow in endpoint BAR test case (Dan Carpenter) - Skip endpoint IRQ test if the IRQ is out of range to avoid false errors (Christian Bruel) - Fix endpoint test case for controllers with fixed-size BARs smaller than requested by the test (Marek Vasut) - Restore inbound translation when disabling doorbell so the endpoint doorbell test case can be run more than once (Niklas Cassel) - Avoid a NULL pointer dereference when releasing DMA channels in endpoint DMA test case (Shin'ichiro Kawasaki) - Convert tegra194 interrupt number to MSI vector to fix endpoint Kselftest MSI_TEST test case (Niklas Cassel) - Reset tegra194 BARs when running in endpoint mode so the BAR tests don't overwrite the ATU settings in BAR4 (Niklas Cassel) - Handle errors in tegra194 BPMP transactions so we don't mistakenly skip future PERST# assertion (Vidya Sagar) AMD MDB PCIe controller driver: - Update DT binding example to separate PERST# to a Root Port stanza to make multiple Root Ports possible in the future (Sai Krishna Musham) - Add driver support for PERST# being described in a Root Port stanza, falling back to the host bridge if not found there (Sai Krishna Musham) Freescale i.MX6 PCIe controller driver: - Enable the 3.3V Vaux supply if available so devices can request wakeup with either Beacon or WAKE# (Richard Zhu) MediaTek PCIe Gen3 controller driver: - Add optional sys clock ready time setting to avoid sys_clk_rdy signal glitching in MT6991 and MT8196 (AngeloGioacchino Del Regno) - Add DT binding and driver support for MT6991 and MT8196 (AngeloGioacchino Del Regno) NVIDIA Tegra PCIe controller driver: - When asserting PERST#, disable the controller instead of mistakenly disabling the PLL twice (Nagarjuna Kristam) - Convert struct tegra_msi mask_lock to raw spinlock to avoid a lock nesting error (Marek Vasut) Qualcomm PCIe controller driver: - Select PCI Power Control Slot driver so slot voltage rails can be turned on/off if described in Root Port devicetree node (Qiang Yu) - Parse only PCI bridge child nodes in devicetree, skipping unrelated nodes such as OPP (Operating Performance Points), which caused probe failures (Krishna Chaitanya Chundru) - Add 8.0 GT/s and 32.0 GT/s equalization settings (Ziyue Zhang) - Consolidate Root Port 'phy' and 'reset' properties in struct qcom_pcie_port, regardless of whether we got them from the Root Port node or the host bridge node (Manivannan Sadhasivam) - Fetch and map the ELBI register space in the DWC core rather than in each driver individually (Krishna Chaitanya Chundru) - Enable ECAM mechanism in DWC core by setting up iATU with 'CFG Shift Feature' and use this in the qcom driver (Krishna Chaitanya Chundru) - Add SM8750 compatible to qcom,pcie-sm8550.yaml (Krishna Chaitanya Chundru) - Update qcom,pcie-x1e80100.yaml to allow fifth PCIe host on Qualcomm Glymur, which is compatible with X1E80100 but doesn't have the cnoc_sf_axi clock (Qiang Yu) Renesas R-Car PCIe controller driver: - Fix a typo that prevented correct PHY initialization (Marek Vasut) - Add a missing 1ms delay after PWR reset assertion as required by the V4H manual (Marek Vasut) - Assure reset has completed before DBI access to avoid SError (Marek Vasut) - Fix inverted PHY initialization check, which sometimes led to timeouts and failure to start the controller (Marek Vasut) - Pass the correct IRQ domain to generic_handle_domain_irq() to fix a regression when converting to msi_create_parent_irq_domain() (Claudiu Beznea) - Drop the spinlock protecting the PMSR register - it's no longer required since pci_lock already serializes accesses (Marek Vasut) - Convert struct rcar_msi mask_lock to raw spinlock to avoid a lock nesting error (Marek Vasut) SOPHGO PCIe controller driver: - Check for existence of struct cdns_pcie.ops before using it to allow Cadence drivers that don't need to supply ops (Chen Wang) - Add DT binding and driver for the SOPHGO SG2042 PCIe controller (Chen Wang) STMicroelectronics STM32MP25 PCIe controller driver: - Update pinctrl documentation of initial states and use in runtime suspend/resume (Christian Bruel) - Add pinctrl_pm_select_init_state() for use by stm32 driver, which needs it during resume (Christian Bruel) - Add devicetree bindings and drivers for the STMicroelectronics STM32MP25 in host and endpoint modes (Christian Bruel) Synopsys DesignWare PCIe controller driver: - Add support for x16 in devicetree 'num-lanes' property (Konrad Dybcio) - Verify that if DT specifies a single IRQ for all eDMA channels, it is named 'dma' (Niklas Cassel) TI J721E PCIe driver: - Add MODULE_DEVICE_TABLE() so driver can be autoloaded (Siddharth Vadapalli) - Power controller off before configuring the glue layer so the controller latches the correct values on power-on (Siddharth Vadapalli) TI Keystone PCIe controller driver: - Use devm_request_irq() so 'ks-pcie-error-irq' is freed when driver exits with error (Siddharth Vadapalli) - Add Peripheral Virtualization Unit (PVU), which restricts DMA from PCIe devices to specific regions of host memory, to the ti,am65 binding (Jan Kiszka) Xilinx NWL PCIe controller driver: - Clear bootloader E_ECAM_CONTROL before merging in the new driver value to avoid writing invalid values (Jani Nurminen)" * tag 'pci-v6.18-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci: (141 commits) PCI/AER: Avoid NULL pointer dereference in aer_ratelimit() MAINTAINERS: Add entry for ST STM32MP25 PCIe drivers PCI: stm32-ep: Add PCIe Endpoint support for STM32MP25 dt-bindings: PCI: Add STM32MP25 PCIe Endpoint bindings PCI: stm32: Add PCIe host support for STM32MP25 PCI: xilinx-nwl: Fix ECAM programming PCI: j721e: Fix incorrect error message in probe() PCI: keystone: Use devm_request_irq() to free "ks-pcie-error-irq" on exit dt-bindings: PCI: qcom,pcie-x1e80100: Set clocks minItems for the fifth Glymur PCIe Controller PCI: dwc: Support 16-lane operation PCI: Add lockdep assertion in pci_stop_and_remove_bus_device() PCI/IOV: Add PCI rescan-remove locking when enabling/disabling SR-IOV PCI: rcar-host: Convert struct rcar_msi mask_lock into raw spinlock PCI: tegra194: Rename 'root_bus' to 'root_port_bus' in tegra_pcie_downstream_dev_to_D0() PCI: tegra: Convert struct tegra_msi mask_lock into raw spinlock PCI: rcar-gen4: Fix inverted break condition in PHY initialization PCI: rcar-gen4: Assure reset occurs before DBI access PCI: rcar-gen4: Add missing 1ms delay after PWR reset assertion PCI: Set up bridge resources earlier PCI: rcar-host: Drop PMSR spinlock ...
2025-10-03Merge tag 'docs-6.18' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "It has been a relatively busy cycle in docsland, with changes all over: - Bring the kernel memory-model docs into the Sphinx build in the "literal include" mode. - Lots of build-infrastructure work, further cleaning up long-term kernel-doc technical debt. The sphinx-pre-install tool has been converted to Python and updated for current systems. - A new tool to detect when documents have been moved and generate HTML redirects; this can be used on kernel.org (or any other site hosting the rendered docs) to avoid breaking links. - Automated processing of the YAML files describing the netlink protocol. - A significant update of the maintainer's PGP guide. ... and a seemingly endless series of typo fixes, build-problem fixes, etc" * tag 'docs-6.18' of git://git.lwn.net/linux: (193 commits) Documentation/features: Update feature lists for 6.17-rc7 docs: remove cdomain.py Documentation/process: submitting-patches: fix typo in "were do" docs: dev-tools/lkmm: Fix typo of missing file extension Documentation: trace: histogram: Convert ftrace docs cross-reference Documentation: trace: histogram-design: Wrap introductory note in note:: directive Documentation: trace: historgram-design: Separate sched_waking histogram section heading and the following diagram Documentation: trace: histogram-design: Trim trailing vertices in diagram explanation text Documentation: trace: histogram: Fix histogram trigger subsection number order docs: driver-api: fix spelling of "buses". Documentation: fbcon: Use admonition directives Documentation: fbcon: Reindent 8th step of attach/detach/unload Documentation: fbcon: Add boot options and attach/detach/unload section headings docs: filesystems: sysfs: add remaining top level sysfs directory descriptions docs: filesystems: sysfs: clarify symlink destinations in dev and bus/devices descriptions docs: filesystems: sysfs: remove top level sysfs net directory docs: maintainer: Fix ambiguous subheading formatting docs: kdoc: a few more dump_typedef() tweaks docs: kdoc: remove redundant comment stripping in dump_typedef() docs: kdoc: remove some dead code in dump_typedef() ...
2025-09-08pinctrl: generic: rename PIN_CONFIG_OUTPUT to LEVELLinus Walleij
This generic pin config property is confusingly named so let's rename it to make things clearer. There are already drivers in the tree that use PIN_CONFIG_OUTPUT to *read* the value of an output driven pin, which is a big semantic confusion for the head: are we then reading the setting of the output or the actual value/level that is put out on the pin? We already have PIN_CONFIG_OUTPUT_ENABLE that turns on driver buffers for output, so this can by logical conclusion only drive the voltage level if it should be any different. But if we read the pin, are we then reading the *setting* of the output value or the *actual* value we can see on the line? If the pin has not first been set into output mode with PIN_CONFIG_OUTPUT_ENABLE, but is instead in some input mode or tristate, what will reading this property actually return? Reading the current users reading this property it is clear that what we read is the logical level of the pin as 0 or 1 depending on if it is low or high. Rename it to PIN_CONFIG_LEVEL so it is crystal clear that we set or read the voltage level of the pin and nothing else. Acked-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2025-08-29docs: driver-api pinctrl cleanupAlex Tran
Replace FIXME comments in the pinctrl documentation example with proper cleanup code: - Add devm_pinctrl_put() calls in error paths (pinctrl_lookup_state, pinctrl_select_state) after successful devm_pinctrl_get() - Set foo->p to NULL when devm_pinctrl_get() fails - Add ret variable for cleaner error handling - provides proper example of pinctrl resource management on failure Signed-off-by: Alex Tran <alex.t.tran@gmail.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20250827074525.685863-1-alex.t.tran@gmail.com
2025-08-27Documentation: pinctrl: Describe PM helper functions for standard states.Christian Bruel
Clarify documentation for predefined standard state names 'default', 'init', 'sleep', 'idle' and their associated PM API. Signed-off-by: Christian Bruel <christian.bruel@foss.st.com> Signed-off-by: Manivannan Sadhasivam <mani@kernel.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Link: https://patch.msgid.link/20250820075411.1178729-2-christian.bruel@foss.st.com
2024-07-16docs/pinctrl: fix typo in mapping exampleMarc Ferland
Small typo. The device name in the example should be "foo-i2c.0" and not "foo-i2c.o". Signed-off-by: Marc Ferland <marc.ferland@sonatest.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20240709183919.3337131-1-marc.ferland@sonatest.com
2023-02-22Merge tag 'docs-6.3' of git://git.lwn.net/linuxLinus Torvalds
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 ...
2023-02-02Documentation: driver-api: correct spellingRandy Dunlap
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>
2023-01-17pinctrl: Proofreading and updating the documentation (part 2)Bagas Sanjaya
Do the following: - update the "Definitions" style in two sections - don't use "I" for technical documentation - inline the remaining (variables, function names, file paths) Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Linus Walleij <linus.walleij@linaro.org>
2023-01-17pinctrl: Proofreading and updating the documentation accordinglyAndy Shevchenko
Proofreading and updating the documentation accordingly, i.e. fixed: - ambiguity of foo_set_mux() implementation and explanations - semantics in some of the examples, e.g. _probe() --> _init() - references to the callbacks to make them start with dot - references to the legacy API by replacing them with newer one - indentation in some of the examples - double words or phrases updated: - unsigned --> unsigned int in some of the examples - use struct pingroup and PINCTRL_PINGROUP() in some of the examples - use struct pinfunction and PINCTRL_PINFUNCTION() in some of the examples and enabled: - syntax highlighting for the examples in the programming languages - chapter references Yet to clarify: - "gpioN" menton for the default function when requesting GPIO Co-developed-by: Bagas Sanjaya <bagasdotme@gmail.com> Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Linus Walleij <linus.walleij@linaro.org>
2022-11-09docs/pinctrl: fix runtime pinmuxing exampleSiarhei Volkau
The example declares "struct pinctrl *p" but refers to "foo->p" which isn't declared in the context of the example. Signed-off-by: Siarhei Volkau <lis8215@gmail.com> Link: https://lore.kernel.org/r/20221101205159.1468069-3-lis8215@gmail.com Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2022-11-09docs/pinctrl: fix pinctrl_select_state examplesSiarhei Volkau
The function requires two arguments. Signed-off-by: Siarhei Volkau <lis8215@gmail.com> Link: https://lore.kernel.org/r/20221101205159.1468069-2-lis8215@gmail.com Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2021-05-28docs/pinctrl: fix the reference to the u300 platformDario Binacchi
With commit ce1380c9f4bc ("ARM: remove u300 platform") it is wrong to use arch/arm/mach-u300/Kconfig file as example. Since the u300 platform has been replaced by the u8500, let's use its Kconfig as example. Signed-off-by: Dario Binacchi <dariobin@libero.it> Link: https://lore.kernel.org/r/20210527201309.13308-1-dariobin@libero.it Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2021-04-08docs: pin-control: Fix error path for control state exampleNiklas Söderlund
The error is constructed using the wrong variable. Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se> Link: https://lore.kernel.org/r/20210328164222.720525-1-niklas.soderlund+renesas@ragnatech.se Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2021-03-10docs/pinctrl: document debugfs filesDrew Fustini
Document debugfs directories and files created for pinctrl subsystem. Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Drew Fustini <drew@beagleboard.org> Link: https://lore.kernel.org/r/20210302053059.1049035-5-drew@beagleboard.org Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2021-03-10Documentation: rename pinctl to pin-controlDrew Fustini
pinctl is not ideal as pinctrl (with an 'r') is much more common. Linus state that pin-control.rst would be the best name for the documentation. Link: https://lore.kernel.org/linux-gpio/20210126050817.GA187797@x1/#t Suggested-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Drew Fustini <drew@beagleboard.org> Link: https://lore.kernel.org/r/20210302053059.1049035-4-drew@beagleboard.org Signed-off-by: Linus Walleij <linus.walleij@linaro.org>