Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted

Pull networking updates from Jakub Kicinski:
 "Core:

   - Add dedicated kmem_cache for typical/small skb->head, avoid having
     to access struct page at kfree time, and improve memory use.

   - Introduce sysctl to set default RPS configuration for new netdevs.

   - Define Netlink protocol specification format which can be used to
     describe messages used by each family and auto-generate parsers.
     Add tools for generating kernel data structures and uAPI headers.

   - Expose all net/core sysctls inside netns.

   - Remove 4s sleep in netpoll if carrier is instantly detected on
     boot.

   - Add configurable limit of MDB entries per port, and port-vlan.

   - Continue populating drop reasons throughout the stack.

   - Retire a handful of legacy Qdiscs and classifiers.

  Protocols:

   - Support IPv4 big TCP (TSO frames larger than 64kB).

   - Add IP_LOCAL_PORT_RANGE socket option, to control local port range
     on socket by socket basis.

   - Track and report in procfs number of MPTCP sockets used.

   - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path
     manager.

   - IPv6: don't check net.ipv6.route.max_size and rely on garbage
     collection to free memory (similarly to IPv4).

   - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986).

   - ICMP: add per-rate limit counters.

   - Add support for user scanning requests in ieee802154.

   - Remove static WEP support.

   - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate
     reporting.

   - WiFi 7 EHT channel puncturing support (client & AP).

  BPF:

   - Add a rbtree data structure following the "next-gen data structure"
     precedent set by recently added linked list, that is, by using
     kfunc + kptr instead of adding a new BPF map type.

   - Expose XDP hints via kfuncs with initial support for RX hash and
     timestamp metadata.

   - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to
     better support decap on GRE tunnel devices not operating in collect
     metadata.

   - Improve x86 JIT's codegen for PROBE_MEM runtime error checks.

   - Remove the need for trace_printk_lock for bpf_trace_printk and
     bpf_trace_vprintk helpers.

   - Extend libbpf's bpf_tracing.h support for tracing arguments of
     kprobes/uprobes and syscall as a special case.

   - Significantly reduce the search time for module symbols by
     livepatch and BPF.

   - Enable cpumasks to be used as kptrs, which is useful for tracing
     programs tracking which tasks end up running on which CPUs in
     different time intervals.

   - Add support for BPF trampoline on s390x and riscv64.

   - Add capability to export the XDP features supported by the NIC.

   - Add __bpf_kfunc tag for marking kernel functions as kfuncs.

   - Add cgroup.memory=nobpf kernel parameter option to disable BPF
     memory accounting for container environments.

  Netfilter:

   - Remove the CLUSTERIP target. It has been marked as obsolete for
     years, and we still have WARN splats wrt races of the out-of-band
     /proc interface installed by this target.

   - Add 'destroy' commands to nf_tables. They are identical to the
     existing 'delete' commands, but do not return an error if the
     referenced object (set, chain, rule...) did not exist.

  Driver API:

   - Improve cpumask_local_spread() locality to help NICs set the right
     IRQ affinity on AMD platforms.

   - Separate C22 and C45 MDIO bus transactions more clearly.

   - Introduce new DCB table to control DSCP rewrite on egress.

   - Support configuration of Physical Layer Collision Avoidance (PLCA)
     Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of
     shared medium Ethernet.

   - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing
     preemption of low priority frames by high priority frames.

   - Add support for controlling MACSec offload using netlink SET.

   - Rework devlink instance refcounts to allow registration and
     de-registration under the instance lock. Split the code into
     multiple files, drop some of the unnecessarily granular locks and
     factor out common parts of netlink operation handling.

   - Add TX frame aggregation parameters (for USB drivers).

   - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning
     messages with notifications for debug.

   - Allow offloading of UDP NEW connections via act_ct.

   - Add support for per action HW stats in TC.

   - Support hardware miss to TC action (continue processing in SW from
     a specific point in the action chain).

   - Warn if old Wireless Extension user space interface is used with
     modern cfg80211/mac80211 drivers. Do not support Wireless
     Extensions for Wi-Fi 7 devices at all. Everyone should switch to
     using nl80211 interface instead.

   - Improve the CAN bit timing configuration. Use extack to return
     error messages directly to user space, update the SJW handling,
     including the definition of a new default value that will benefit
     CAN-FD controllers, by increasing their oscillator tolerance.

  New hardware / drivers:

   - Ethernet:
      - nVidia BlueField-3 support (control traffic driver)
      - Ethernet support for imx93 SoCs
      - Motorcomm yt8531 gigabit Ethernet PHY
      - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA)
      - Microchip LAN8841 PHY (incl. cable diagnostics and PTP)
      - Amlogic gxl MDIO mux

   - WiFi:
      - RealTek RTL8188EU (rtl8xxxu)
      - Qualcomm Wi-Fi 7 devices (ath12k)

   - CAN:
      - Renesas R-Car V4H

  Drivers:

   - Bluetooth:
      - Set Per Platform Antenna Gain (PPAG) for Intel controllers.

   - Ethernet NICs:
      - Intel (1G, igc):
         - support TSN / Qbv / packet scheduling features of i226 model
      - Intel (100G, ice):
         - use GNSS subsystem instead of TTY
         - multi-buffer XDP support
         - extend support for GPIO pins to E823 devices
      - nVidia/Mellanox:
         - update the shared buffer configuration on PFC commands
         - implement PTP adjphase function for HW offset control
         - TC support for Geneve and GRE with VF tunnel offload
         - more efficient crypto key management method
         - multi-port eswitch support
      - Netronome/Corigine:
         - add DCB IEEE support
         - support IPsec offloading for NFP3800
      - Freescale/NXP (enetc):
         - support XDP_REDIRECT for XDP non-linear buffers
         - improve reconfig, avoid link flap and waiting for idle
         - support MAC Merge layer
      - Other NICs:
         - sfc/ef100: add basic devlink support for ef100
         - ionic: rx_push mode operation (writing descriptors via MMIO)
         - bnxt: use the auxiliary bus abstraction for RDMA
         - r8169: disable ASPM and reset bus in case of tx timeout
         - cpsw: support QSGMII mode for J721e CPSW9G
         - cpts: support pulse-per-second output
         - ngbe: add an mdio bus driver
         - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing
         - r8152: handle devices with FW with NCM support
         - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation
         - virtio-net: support multi buffer XDP
         - virtio/vsock: replace virtio_vsock_pkt with sk_buff
         - tsnep: XDP support

   - Ethernet high-speed switches:
      - nVidia/Mellanox (mlxsw):
         - add support for latency TLV (in FW control messages)
      - Microchip (sparx5):
         - separate explicit and implicit traffic forwarding rules, make
           the implicit rules always active
         - add support for egress DSCP rewrite
         - IS0 VCAP support (Ingress Classification)
         - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS
           etc.)
         - ES2 VCAP support (Egress Access Control)
         - support for Per-Stream Filtering and Policing (802.1Q,
           8.6.5.1)

   - Ethernet embedded switches:
      - Marvell (mv88e6xxx):
         - add MAB (port auth) offload support
         - enable PTP receive for mv88e6390
      - NXP (ocelot):
         - support MAC Merge layer
         - support for the the vsc7512 internal copper phys
      - Microchip:
         - lan9303: convert to PHYLINK
         - lan966x: support TC flower filter statistics
         - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x
         - lan937x: support Credit Based Shaper configuration
         - ksz9477: support Energy Efficient Ethernet
      - other:
         - qca8k: convert to regmap read/write API, use bulk operations
         - rswitch: Improve TX timestamp accuracy

   - Intel WiFi (iwlwifi):
      - EHT (Wi-Fi 7) rate reporting
      - STEP equalizer support: transfer some STEP (connection to radio
        on platforms with integrated wifi) related parameters from the
        BIOS to the firmware.

   - Qualcomm 802.11ax WiFi (ath11k):
      - IPQ5018 support
      - Fine Timing Measurement (FTM) responder role support
      - channel 177 support

   - MediaTek WiFi (mt76):
      - per-PHY LED support
      - mt7996: EHT (Wi-Fi 7) support
      - Wireless Ethernet Dispatch (WED) reset support
      - switch to using page pool allocator

   - RealTek WiFi (rtw89):
      - support new version of Bluetooth co-existance

   - Mobile:
      - rmnet: support TX aggregation"

* tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits)
  page_pool: add a comment explaining the fragment counter usage
  net: ethtool: fix __ethtool_dev_mm_supported() implementation
  ethtool: pse-pd: Fix double word in comments
  xsk: add linux/vmalloc.h to xsk.c
  sefltests: netdevsim: wait for devlink instance after netns removal
  selftest: fib_tests: Always cleanup before exit
  net/mlx5e: Align IPsec ASO result memory to be as required by hardware
  net/mlx5e: TC, Set CT miss to the specific ct action instance
  net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG
  net/mlx5: Refactor tc miss handling to a single function
  net/mlx5: Kconfig: Make tc offload depend on tc skb extension
  net/sched: flower: Support hardware miss to tc action
  net/sched: flower: Move filter handle initialization earlier
  net/sched: cls_api: Support hardware miss to tc action
  net/sched: Rename user cookie and act cookie
  sfc: fix builds without CONFIG_RTC_LIB
  sfc: clean up some inconsistent indentings
  net/mlx4_en: Introduce flexible array to silence overflow warning
  net: lan966x: Fix possible deadlock inside PTP
  net/ulp: Remove redundant ->clone() test in inet_clone_ulp().
  ...

1 files changed, 468 insertions, 0 deletions

diff --git a/Documentation/driver-api/gpio/consumer.rst b/Documentation/driver-api/gpio/consumer.rst
new file mode 100644
index 000000000..de6fc79ad
--- /dev/null
+++ b/Documentation/driver-api/gpio/consumer.rst
@@ -0,0 +1,468 @@
+==================================
+GPIO Descriptor Consumer Interface
+==================================
+
+This document describes the consumer interface of the GPIO framework. Note that
+it describes the new descriptor-based interface. For a description of the
+deprecated integer-based GPIO interface please refer to legacy.rst.
+
+
+Guidelines for GPIOs consumers
+==============================
+
+Drivers that can't work without standard GPIO calls should have Kconfig entries
+that depend on GPIOLIB or select GPIOLIB. The functions that allow a driver to
+obtain and use GPIOs are available by including the following file::
+
+	#include <linux/gpio/consumer.h>
+
+There are static inline stubs for all functions in the header file in the case
+where GPIOLIB is disabled. When these stubs are called they will emit
+warnings. These stubs are used for two use cases:
+
+- Simple compile coverage with e.g. COMPILE_TEST - it does not matter that
+  the current platform does not enable or select GPIOLIB because we are not
+  going to execute the system anyway.
+
+- Truly optional GPIOLIB support - where the driver does not really make use
+  of the GPIOs on certain compile-time configurations for certain systems, but
+  will use it under other compile-time configurations. In this case the
+  consumer must make sure not to call into these functions, or the user will
+  be met with console warnings that may be perceived as intimidating.
+
+All the functions that work with the descriptor-based GPIO interface are
+prefixed with ``gpiod_``. The ``gpio_`` prefix is used for the legacy
+interface. No other function in the kernel should use these prefixes. The use
+of the legacy functions is strongly discouraged, new code should use
+<linux/gpio/consumer.h> and descriptors exclusively.
+
+
+Obtaining and Disposing GPIOs
+=============================
+
+With the descriptor-based interface, GPIOs are identified with an opaque,
+non-forgeable handler that must be obtained through a call to one of the
+gpiod_get() functions. Like many other kernel subsystems, gpiod_get() takes the
+device that will use the GPIO and the function the requested GPIO is supposed to
+fulfill::
+
+	struct gpio_desc *gpiod_get(struct device *dev, const char *con_id,
+				    enum gpiod_flags flags)
+
+If a function is implemented by using several GPIOs together (e.g. a simple LED
+device that displays digits), an additional index argument can be specified::
+
+	struct gpio_desc *gpiod_get_index(struct device *dev,
+					  const char *con_id, unsigned int idx,
+					  enum gpiod_flags flags)
+
+For a more detailed description of the con_id parameter in the DeviceTree case
+see Documentation/driver-api/gpio/board.rst
+
+The flags parameter is used to optionally specify a direction and initial value
+for the GPIO. Values can be:
+
+* GPIOD_ASIS or 0 to not initialize the GPIO at all. The direction must be set
+  later with one of the dedicated functions.
+* GPIOD_IN to initialize the GPIO as input.
+* GPIOD_OUT_LOW to initialize the GPIO as output with a value of 0.
+* GPIOD_OUT_HIGH to initialize the GPIO as output with a value of 1.
+* GPIOD_OUT_LOW_OPEN_DRAIN same as GPIOD_OUT_LOW but also enforce the line
+  to be electrically used with open drain.
+* GPIOD_OUT_HIGH_OPEN_DRAIN same as GPIOD_OUT_HIGH but also enforce the line
+  to be electrically used with open drain.
+
+Note that the initial value is *logical* and the physical line level depends on
+whether the line is configured active high or active low (see
+:ref:`active_low_semantics`).
+
+The two last flags are used for use cases where open drain is mandatory, such
+as I2C: if the line is not already configured as open drain in the mappings
+(see board.rst), then open drain will be enforced anyway and a warning will be
+printed that the board configuration needs to be updated to match the use case.
+
+Both functions return either a valid GPIO descriptor, or an error code checkable
+with IS_ERR() (they will never return a NULL pointer). -ENOENT will be returned
+if and only if no GPIO has been assigned to the device/function/index triplet,
+other error codes are used for cases where a GPIO has been assigned but an error
+occurred while trying to acquire it. This is useful to discriminate between mere
+errors and an absence of GPIO for optional GPIO parameters. For the common
+pattern where a GPIO is optional, the gpiod_get_optional() and
+gpiod_get_index_optional() functions can be used. These functions return NULL
+instead of -ENOENT if no GPIO has been assigned to the requested function::
+
+	struct gpio_desc *gpiod_get_optional(struct device *dev,
+					     const char *con_id,
+					     enum gpiod_flags flags)
+
+	struct gpio_desc *gpiod_get_index_optional(struct device *dev,
+						   const char *con_id,
+						   unsigned int index,
+						   enum gpiod_flags flags)
+
+Note that gpio_get*_optional() functions (and their managed variants), unlike
+the rest of gpiolib API, also return NULL when gpiolib support is disabled.
+This is helpful to driver authors, since they do not need to special case
+-ENOSYS return codes.  System integrators should however be careful to enable
+gpiolib on systems that need it.
+
+For a function using multiple GPIOs all of those can be obtained with one call::
+
+	struct gpio_descs *gpiod_get_array(struct device *dev,
+					   const char *con_id,
+					   enum gpiod_flags flags)
+
+This function returns a struct gpio_descs which contains an array of
+descriptors.  It also contains a pointer to a gpiolib private structure which,
+if passed back to get/set array functions, may speed up I/O processing::
+
+	struct gpio_descs {
+		struct gpio_array *info;
+		unsigned int ndescs;
+		struct gpio_desc *desc[];
+	}
+
+The following function returns NULL instead of -ENOENT if no GPIOs have been
+assigned to the requested function::
+
+	struct gpio_descs *gpiod_get_array_optional(struct device *dev,
+						    const char *con_id,
+						    enum gpiod_flags flags)
+
+Device-managed variants of these functions are also defined::
+
+	struct gpio_desc *devm_gpiod_get(struct device *dev, const char *con_id,
+					 enum gpiod_flags flags)
+
+	struct gpio_desc *devm_gpiod_get_index(struct device *dev,
+					       const char *con_id,
+					       unsigned int idx,
+					       enum gpiod_flags flags)
+
+	struct gpio_desc *devm_gpiod_get_optional(struct device *dev,
+						  const char *con_id,
+						  enum gpiod_flags flags)
+
+	struct gpio_desc *devm_gpiod_get_index_optional(struct device *dev,
+							const char *con_id,
+							unsigned int index,
+							enum gpiod_flags flags)
+
+	struct gpio_descs *devm_gpiod_get_array(struct device *dev,
+						const char *con_id,
+						enum gpiod_flags flags)
+
+	struct gpio_descs *devm_gpiod_get_array_optional(struct device *dev,
+							 const char *con_id,
+							 enum gpiod_flags flags)
+
+A GPIO descriptor can be disposed of using the gpiod_put() function::
+
+	void gpiod_put(struct gpio_desc *desc)
+
+For an array of GPIOs this function can be used::
+
+	void gpiod_put_array(struct gpio_descs *descs)
+
+It is strictly forbidden to use a descriptor after calling these functions.
+It is also not allowed to individually release descriptors (using gpiod_put())
+from an array acquired with gpiod_get_array().
+
+The device-managed variants are, unsurprisingly::
+
+	void devm_gpiod_put(struct device *dev, struct gpio_desc *desc)
+
+	void devm_gpiod_put_array(struct device *dev, struct gpio_descs *descs)
+
+
+Using GPIOs
+===========
+
+Setting Direction
+-----------------
+The first thing a driver must do with a GPIO is setting its direction. If no
+direction-setting flags have been given to gpiod_get*(), this is done by
+invoking one of the gpiod_direction_*() functions::
+
+	int gpiod_direction_input(struct gpio_desc *desc)
+	int gpiod_direction_output(struct gpio_desc *desc, int value)
+
+The return value is zero for success, else a negative errno. It should be
+checked, since the get/set calls don't return errors and since misconfiguration
+is possible. You should normally issue these calls from a task context. However,
+for spinlock-safe GPIOs it is OK to use them before tasking is enabled, as part
+of early board setup.
+
+For output GPIOs, the value provided becomes the initial output value. This
+helps avoid signal glitching during system startup.
+
+A driver can also query the current direction of a GPIO::
+
+	int gpiod_get_direction(const struct gpio_desc *desc)
+
+This function returns 0 for output, 1 for input, or an error code in case of error.
+
+Be aware that there is no default direction for GPIOs. Therefore, **using a GPIO
+without setting its direction first is illegal and will result in undefined
+behavior!**
+
+
+Spinlock-Safe GPIO Access
+-------------------------
+Most GPIO controllers can be accessed with memory read/write instructions. Those
+don't need to sleep, and can safely be done from inside hard (non-threaded) IRQ
+handlers and similar contexts.
+
+Use the following calls to access GPIOs from an atomic context::
+
+	int gpiod_get_value(const struct gpio_desc *desc);
+	void gpiod_set_value(struct gpio_desc *desc, int value);
+
+The values are boolean, zero for low, nonzero for high. When reading the value
+of an output pin, the value returned should be what's seen on the pin. That
+won't always match the specified output value, because of issues including
+open-drain signaling and output latencies.
+
+The get/set calls do not return errors because "invalid GPIO" should have been
+reported earlier from gpiod_direction_*(). However, note that not all platforms
+can read the value of output pins; those that can't should always return zero.
+Also, using these calls for GPIOs that can't safely be accessed without sleeping
+(see below) is an error.
+
+
+GPIO Access That May Sleep
+--------------------------
+Some GPIO controllers must be accessed using message based buses like I2C or
+SPI. Commands to read or write those GPIO values require waiting to get to the
+head of a queue to transmit a command and get its response. This requires
+sleeping, which can't be done from inside IRQ handlers.
+
+Platforms that support this type of GPIO distinguish them from other GPIOs by
+returning nonzero from this call::
+
+	int gpiod_cansleep(const struct gpio_desc *desc)
+
+To access such GPIOs, a different set of accessors is defined::
+
+	int gpiod_get_value_cansleep(const struct gpio_desc *desc)
+	void gpiod_set_value_cansleep(struct gpio_desc *desc, int value)
+
+Accessing such GPIOs requires a context which may sleep, for example a threaded
+IRQ handler, and those accessors must be used instead of spinlock-safe
+accessors without the cansleep() name suffix.
+
+Other than the fact that these accessors might sleep, and will work on GPIOs
+that can't be accessed from hardIRQ handlers, these calls act the same as the
+spinlock-safe calls.
+
+
+.. _active_low_semantics:
+
+The active low and open drain semantics
+---------------------------------------
+As a consumer should not have to care about the physical line level, all of the
+gpiod_set_value_xxx() or gpiod_set_array_value_xxx() functions operate with
+the *logical* value. With this they take the active low property into account.
+This means that they check whether the GPIO is configured to be active low,
+and if so, they manipulate the passed value before the physical line level is
+driven.
+
+The same is applicable for open drain or open source output lines: those do not
+actively drive their output high (open drain) or low (open source), they just
+switch their output to a high impedance value. The consumer should not need to
+care. (For details read about open drain in driver.rst.)
+
+With this, all the gpiod_set_(array)_value_xxx() functions interpret the
+parameter "value" as "asserted" ("1") or "de-asserted" ("0"). The physical line
+level will be driven accordingly.
+
+As an example, if the active low property for a dedicated GPIO is set, and the
+gpiod_set_(array)_value_xxx() passes "asserted" ("1"), the physical line level
+will be driven low.
+
+To summarize::
+
+  Function (example)                 line property          physical line
+  gpiod_set_raw_value(desc, 0);      don't care             low
+  gpiod_set_raw_value(desc, 1);      don't care             high
+  gpiod_set_value(desc, 0);          default (active high)  low
+  gpiod_set_value(desc, 1);          default (active high)  high
+  gpiod_set_value(desc, 0);          active low             high
+  gpiod_set_value(desc, 1);          active low             low
+  gpiod_set_value(desc, 0);          open drain             low
+  gpiod_set_value(desc, 1);          open drain             high impedance
+  gpiod_set_value(desc, 0);          open source            high impedance
+  gpiod_set_value(desc, 1);          open source            high
+
+It is possible to override these semantics using the set_raw/get_raw functions
+but it should be avoided as much as possible, especially by system-agnostic drivers
+which should not need to care about the actual physical line level and worry about
+the logical value instead.
+
+
+Accessing raw GPIO values
+-------------------------
+Consumers exist that need to manage the logical state of a GPIO line, i.e. the value
+their device will actually receive, no matter what lies between it and the GPIO
+line.
+
+The following set of calls ignore the active-low or open drain property of a GPIO and
+work on the raw line value::
+
+	int gpiod_get_raw_value(const struct gpio_desc *desc)
+	void gpiod_set_raw_value(struct gpio_desc *desc, int value)
+	int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc)
+	void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value)
+	int gpiod_direction_output_raw(struct gpio_desc *desc, int value)
+
+The active low state of a GPIO can also be queried and toggled using the
+following calls::
+
+	int gpiod_is_active_low(const struct gpio_desc *desc)
+	void gpiod_toggle_active_low(struct gpio_desc *desc)
+
+Note that these functions should only be used with great moderation; a driver
+should not have to care about the physical line level or open drain semantics.
+
+
+Access multiple GPIOs with a single function call
+-------------------------------------------------
+The following functions get or set the values of an array of GPIOs::
+
+	int gpiod_get_array_value(unsigned int array_size,
+				  struct gpio_desc **desc_array,
+				  struct gpio_array *array_info,
+				  unsigned long *value_bitmap);
+	int gpiod_get_raw_array_value(unsigned int array_size,
+				      struct gpio_desc **desc_array,
+				      struct gpio_array *array_info,
+				      unsigned long *value_bitmap);
+	int gpiod_get_array_value_cansleep(unsigned int array_size,
+					   struct gpio_desc **desc_array,
+					   struct gpio_array *array_info,
+					   unsigned long *value_bitmap);
+	int gpiod_get_raw_array_value_cansleep(unsigned int array_size,
+					   struct gpio_desc **desc_array,
+					   struct gpio_array *array_info,
+					   unsigned long *value_bitmap);
+
+	int gpiod_set_array_value(unsigned int array_size,
+				  struct gpio_desc **desc_array,
+				  struct gpio_array *array_info,
+				  unsigned long *value_bitmap)
+	int gpiod_set_raw_array_value(unsigned int array_size,
+				      struct gpio_desc **desc_array,
+				      struct gpio_array *array_info,
+				      unsigned long *value_bitmap)
+	int gpiod_set_array_value_cansleep(unsigned int array_size,
+					   struct gpio_desc **desc_array,
+					   struct gpio_array *array_info,
+					   unsigned long *value_bitmap)
+	int gpiod_set_raw_array_value_cansleep(unsigned int array_size,
+					       struct gpio_desc **desc_array,
+					       struct gpio_array *array_info,
+					       unsigned long *value_bitmap)
+
+The array can be an arbitrary set of GPIOs. The functions will try to access
+GPIOs belonging to the same bank or chip simultaneously if supported by the
+corresponding chip driver. In that case a significantly improved performance
+can be expected. If simultaneous access is not possible the GPIOs will be
+accessed sequentially.
+
+The functions take four arguments:
+
+	* array_size	- the number of array elements
+	* desc_array	- an array of GPIO descriptors
+	* array_info	- optional information obtained from gpiod_get_array()
+	* value_bitmap	- a bitmap to store the GPIOs' values (get) or
+          a bitmap of values to assign to the GPIOs (set)
+
+The descriptor array can be obtained using the gpiod_get_array() function
+or one of its variants. If the group of descriptors returned by that function
+matches the desired group of GPIOs, those GPIOs can be accessed by simply using
+the struct gpio_descs returned by gpiod_get_array()::
+
+	struct gpio_descs *my_gpio_descs = gpiod_get_array(...);
+	gpiod_set_array_value(my_gpio_descs->ndescs, my_gpio_descs->desc,
+			      my_gpio_descs->info, my_gpio_value_bitmap);
+
+It is also possible to access a completely arbitrary array of descriptors. The
+descriptors may be obtained using any combination of gpiod_get() and
+gpiod_get_array(). Afterwards the array of descriptors has to be setup
+manually before it can be passed to one of the above functions.  In that case,
+array_info should be set to NULL.
+
+Note that for optimal performance GPIOs belonging to the same chip should be
+contiguous within the array of descriptors.
+
+Still better performance may be achieved if array indexes of the descriptors
+match hardware pin numbers of a single chip.  If an array passed to a get/set
+array function matches the one obtained from gpiod_get_array() and array_info
+associated with the array is also passed, the function may take a fast bitmap
+processing path, passing the value_bitmap argument directly to the respective
+.get/set_multiple() callback of the chip.  That allows for utilization of GPIO
+banks as data I/O ports without much loss of performance.
+
+The return value of gpiod_get_array_value() and its variants is 0 on success
+or negative on error. Note the difference to gpiod_get_value(), which returns
+0 or 1 on success to convey the GPIO value. With the array functions, the GPIO
+values are stored in value_array rather than passed back as return value.
+
+
+GPIOs mapped to IRQs
+--------------------
+GPIO lines can quite often be used as IRQs. You can get the IRQ number
+corresponding to a given GPIO using the following call::
+
+	int gpiod_to_irq(const struct gpio_desc *desc)
+
+It will return an IRQ number, or a negative errno code if the mapping can't be
+done (most likely because that particular GPIO cannot be used as IRQ). It is an
+unchecked error to use a GPIO that wasn't set up as an input using
+gpiod_direction_input(), or to use an IRQ number that didn't originally come
+from gpiod_to_irq(). gpiod_to_irq() is not allowed to sleep.
+
+Non-error values returned from gpiod_to_irq() can be passed to request_irq() or
+free_irq(). They will often be stored into IRQ resources for platform devices,
+by the board-specific initialization code. Note that IRQ trigger options are
+part of the IRQ interface, e.g. IRQF_TRIGGER_FALLING, as are system wakeup
+capabilities.
+
+
+GPIOs and ACPI
+==============
+
+On ACPI systems, GPIOs are described by GpioIo()/GpioInt() resources listed by
+the _CRS configuration objects of devices.  Those resources do not provide
+connection IDs (names) for GPIOs, so it is necessary to use an additional
+mechanism for this purpose.
+
+Systems compliant with ACPI 5.1 or newer may provide a _DSD configuration object
+which, among other things, may be used to provide connection IDs for specific
+GPIOs described by the GpioIo()/GpioInt() resources in _CRS.  If that is the
+case, it will be handled by the GPIO subsystem automatically.  However, if the
+_DSD is not present, the mappings between GpioIo()/GpioInt() resources and GPIO
+connection IDs need to be provided by device drivers.
+
+For details refer to Documentation/firmware-guide/acpi/gpio-properties.rst
+
+
+Interacting With the Legacy GPIO Subsystem
+==========================================
+Many kernel subsystems and drivers still handle GPIOs using the legacy
+integer-based interface. It is strongly recommended to update these to the new
+gpiod interface. For cases where both interfaces need to be used, the following
+two functions allow to convert a GPIO descriptor into the GPIO integer namespace
+and vice-versa::
+
+	int desc_to_gpio(const struct gpio_desc *desc)
+	struct gpio_desc *gpio_to_desc(unsigned gpio)
+
+The GPIO number returned by desc_to_gpio() can safely be used as a parameter of
+the gpio\_*() functions for as long as the GPIO descriptor `desc` is not freed.
+All the same, a GPIO number passed to gpio_to_desc() must first be properly
+acquired using e.g. gpio_request_one(), and the returned GPIO descriptor is only
+considered valid until that GPIO number is released using gpio_free().
+
+Freeing a GPIO obtained by one API with the other API is forbidden and an
+unchecked error.