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, 641 insertions, 0 deletions

diff --git a/Documentation/hwmon/lm90.rst b/Documentation/hwmon/lm90.rst
new file mode 100644
index 000000000..23af17a0a
--- /dev/null
+++ b/Documentation/hwmon/lm90.rst
@@ -0,0 +1,641 @@
+Kernel driver lm90
+==================
+
+Supported chips:
+
+  * National Semiconductor LM84
+
+    Prefix: 'lm84'
+
+    Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e
+
+    Datasheet: Publicly available at the National Semiconductor website
+
+  * National Semiconductor LM90
+
+    Prefix: 'lm90'
+
+    Addresses scanned: I2C 0x4c
+
+    Datasheet: Publicly available at the National Semiconductor website
+
+	       http://www.national.com/pf/LM/LM90.html
+
+  * National Semiconductor LM89
+
+    Prefix: 'lm89' (no auto-detection)
+
+    Addresses scanned: I2C 0x4c and 0x4d
+
+    Datasheet: Publicly available at the National Semiconductor website
+
+	       http://www.national.com/mpf/LM/LM89.html
+
+  * National Semiconductor LM99
+
+    Prefix: 'lm99'
+
+    Addresses scanned: I2C 0x4c and 0x4d
+
+    Datasheet: Publicly available at the National Semiconductor website
+
+	       http://www.national.com/pf/LM/LM99.html
+
+  * National Semiconductor LM86
+
+    Prefix: 'lm86'
+
+    Addresses scanned: I2C 0x4c
+
+    Datasheet: Publicly available at the National Semiconductor website
+
+	       http://www.national.com/mpf/LM/LM86.html
+
+  * Analog Devices ADM1020
+
+    Prefix: 'adm1020'
+
+    Addresses scanned: I2C 0x4c - 0x4e
+
+    Datasheet: Publicly available at the Analog Devices website
+
+  * Analog Devices ADM1021
+
+    Prefix: 'adm1021'
+
+    Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e
+
+    Datasheet: Publicly available at the Analog Devices website
+
+  * Analog Devices ADM1021A/ADM1023
+
+    Prefix: 'adm1023'
+
+    Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e
+
+    Datasheet: Publicly available at the Analog Devices website
+
+  * Analog Devices ADM1032
+
+    Prefix: 'adm1032'
+
+    Addresses scanned: I2C 0x4c and 0x4d
+
+    Datasheet: Publicly available at the ON Semiconductor website
+
+	       https://www.onsemi.com/PowerSolutions/product.do?id=ADM1032
+
+  * Analog Devices ADT7461
+
+    Prefix: 'adt7461'
+
+    Addresses scanned: I2C 0x4c and 0x4d
+
+    Datasheet: Publicly available at the ON Semiconductor website
+
+	       https://www.onsemi.com/PowerSolutions/product.do?id=ADT7461
+
+  * Analog Devices ADT7461A
+
+    Prefix: 'adt7461a'
+
+    Addresses scanned: I2C 0x4c and 0x4d
+
+    Datasheet: Publicly available at the ON Semiconductor website
+
+	       https://www.onsemi.com/PowerSolutions/product.do?id=ADT7461A
+
+  * Analog Devices ADT7481
+
+    Prefix: 'adt7481'
+
+    Addresses scanned: I2C 0x4b and 0x4c
+
+    Datasheet: Publicly available at the ON Semiconductor website
+
+	       https://www.onsemi.com/PowerSolutions/product.do?id=ADT7481
+
+  * Analog Devices ADT7482
+
+    Prefix: 'adt7482'
+
+    Addresses scanned: I2C 0x4c
+
+    Datasheet: Publicly available at the ON Semiconductor website
+
+	       https://www.onsemi.com/PowerSolutions/product.do?id=ADT7482
+
+  * Analog Devices ADT7483A
+
+    Prefix: 'adt7483a'
+
+    Addresses scanned: I2C 0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, 0x4c, 0x4d, 0x4e
+
+    Datasheet: Publicly available at the ON Semiconductor website
+
+	       https://www.onsemi.com/PowerSolutions/product.do?id=ADT7483A
+
+  * ON Semiconductor NCT1008
+
+    Prefix: 'nct1008'
+
+    Addresses scanned: I2C 0x4c and 0x4d
+
+    Datasheet: Publicly available at the ON Semiconductor website
+
+	       https://www.onsemi.com/PowerSolutions/product.do?id=NCT1008
+
+  * ON Semiconductor NCT210
+
+    Prefix: 'adm1021'
+
+    Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e
+
+    Datasheet: Publicly available at the ON Semiconductor website
+
+	       https://www.onsemi.com/PowerSolutions/product.do?id=NCT210
+
+  * ON Semiconductor NCT214
+
+    Prefix: 'nct214'
+
+    Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e
+
+    Datasheet: Publicly available at the ON Semiconductor website
+
+	       https://www.onsemi.com/PowerSolutions/product.do?id=NCT214
+
+  * ON Semiconductor NCT218
+
+    Prefix: 'nct218'
+
+    Addresses scanned: I2C 0x4c - 0x4d
+
+    Datasheet: Publicly available at the ON Semiconductor website
+
+	       https://www.onsemi.com/PowerSolutions/product.do?id=NCT218
+
+  * ON Semiconductor NCT72
+
+    Prefix: 'nct72'
+
+    Addresses scanned: I2C 0x4c - 0x4d
+
+    Datasheet: Publicly available at the ON Semiconductor website
+
+	       https://www.onsemi.com/PowerSolutions/product.do?id=NCT72
+
+  * Maxim MAX1617
+
+    Prefix: 'max1617'
+
+    Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e
+
+    Datasheet: Publicly available at the Maxim website
+
+  * Maxim MAX1617A
+
+    Prefix: 'max1617a'
+
+    Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e
+
+    Datasheet: Publicly available at the Maxim website
+
+  * Maxim MAX6642
+
+    Prefix: 'max6642'
+
+    Addresses scanned: I2C 0x48-0x4f
+
+    Datasheet: Publicly available at the Maxim website
+
+	       http://datasheets.maxim-ic.com/en/ds/MAX6642.pdf
+
+  * Maxim MAX6646
+
+    Prefix: 'max6646'
+
+    Addresses scanned: I2C 0x4d
+
+    Datasheet: Publicly available at the Maxim website
+
+	       http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3497
+
+  * Maxim MAX6647
+
+    Prefix: 'max6646'
+
+    Addresses scanned: I2C 0x4e
+
+    Datasheet: Publicly available at the Maxim website
+
+	       http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3497
+
+  * Maxim MAX6648
+
+    Prefix: 'max6648'
+
+    Addresses scanned: I2C 0x4c
+
+    Datasheet: Publicly available at the Maxim website
+
+	       http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3500
+
+  * Maxim MAX6649
+
+    Prefix: 'max6646'
+
+    Addresses scanned: I2C 0x4c
+
+    Datasheet: Publicly available at the Maxim website
+
+	       http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3497
+
+  * Maxim MAX6654
+
+    Prefix: 'max6654'
+
+    Addresses scanned: I2C 0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b,
+
+			   0x4c, 0x4d and 0x4e
+
+    Datasheet: Publicly available at the Maxim website
+
+	       https://www.maximintegrated.com/en/products/sensors/MAX6654.html
+
+  * Maxim MAX6657
+
+    Prefix: 'max6657'
+
+    Addresses scanned: I2C 0x4c
+
+    Datasheet: Publicly available at the Maxim website
+
+	       http://www.maxim-ic.com/quick_view2.cfm/qv_pk/2578
+
+  * Maxim MAX6658
+
+    Prefix: 'max6657'
+
+    Addresses scanned: I2C 0x4c
+
+    Datasheet: Publicly available at the Maxim website
+
+	       http://www.maxim-ic.com/quick_view2.cfm/qv_pk/2578
+
+  * Maxim MAX6659
+
+    Prefix: 'max6659'
+
+    Addresses scanned: I2C 0x4c, 0x4d, 0x4e
+
+    Datasheet: Publicly available at the Maxim website
+
+	       http://www.maxim-ic.com/quick_view2.cfm/qv_pk/2578
+
+  * Maxim MAX6680
+
+    Prefix: 'max6680'
+
+    Addresses scanned: I2C 0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b,
+
+			   0x4c, 0x4d and 0x4e
+
+    Datasheet: Publicly available at the Maxim website
+
+	       http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3370
+
+  * Maxim MAX6681
+
+    Prefix: 'max6680'
+
+    Addresses scanned: I2C 0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b,
+
+			   0x4c, 0x4d and 0x4e
+
+    Datasheet: Publicly available at the Maxim website
+
+	       http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3370
+
+  * Maxim MAX6692
+
+    Prefix: 'max6648'
+
+    Addresses scanned: I2C 0x4c
+
+    Datasheet: Publicly available at the Maxim website
+
+	       http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3500
+
+  * Maxim MAX6695
+
+    Prefix: 'max6695'
+
+    Addresses scanned: I2C 0x18
+
+    Datasheet: Publicly available at the Maxim website
+
+	       http://www.maxim-ic.com/datasheet/index.mvp/id/4199
+
+  * Maxim MAX6696
+
+    Prefix: 'max6695'
+
+    Addresses scanned: I2C 0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b,
+
+			   0x4c, 0x4d and 0x4e
+
+    Datasheet: Publicly available at the Maxim website
+
+	       http://www.maxim-ic.com/datasheet/index.mvp/id/4199
+
+  * Winbond/Nuvoton W83L771W/G
+
+    Prefix: 'w83l771'
+
+    Addresses scanned: I2C 0x4c
+
+    Datasheet: No longer available
+
+  * Winbond/Nuvoton W83L771AWG/ASG
+
+    Prefix: 'w83l771'
+
+    Addresses scanned: I2C 0x4c
+
+    Datasheet: Not publicly available, can be requested from Nuvoton
+
+  * Philips/NXP SA56004X
+
+    Prefix: 'sa56004'
+
+    Addresses scanned: I2C 0x48 through 0x4F
+
+    Datasheet: Publicly available at NXP website
+
+	       http://ics.nxp.com/products/interface/datasheet/sa56004x.pdf
+
+  * GMT G781
+
+    Prefix: 'g781'
+
+    Addresses scanned: I2C 0x4c, 0x4d
+
+    Datasheet: Not publicly available from GMT
+
+  * Texas Instruments TMP451
+
+    Prefix: 'tmp451'
+
+    Addresses scanned: I2C 0x4c
+
+    Datasheet: Publicly available at TI website
+
+	       https://www.ti.com/litv/pdf/sbos686
+
+  * Texas Instruments TMP461
+
+    Prefix: 'tmp461'
+
+    Addresses scanned: I2C 0x48 through 0x4F
+
+    Datasheet: Publicly available at TI website
+
+	       https://www.ti.com/lit/gpn/tmp461
+
+  * Philips NE1617, NE1617A
+
+    Prefix: 'max1617' (probably detected as a max1617)
+
+    Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e
+
+    Datasheets: Publicly available at the Philips website
+
+  * Philips NE1618
+
+    Prefix: 'ne1618'
+
+    Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e
+
+    Datasheets: Publicly available at the Philips website
+
+  * Genesys Logic GL523SM
+
+    Prefix: 'gl523sm'
+
+    Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e
+
+    Datasheet:
+
+  * TI THMC10
+
+    Prefix: 'thmc10'
+
+    Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e
+
+    Datasheet: Publicly available at the TI website
+
+  * Onsemi MC1066
+
+    Prefix: 'mc1066'
+
+    Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e
+
+    Datasheet: Publicly available at the Onsemi website
+
+Author: Jean Delvare <jdelvare@suse.de>
+
+
+Description
+-----------
+
+The LM90 is a digital temperature sensor. It senses its own temperature as
+well as the temperature of up to one external diode. It is compatible
+with many other devices, many of which are supported by this driver.
+
+The family of chips supported by this driver is derived from MAX1617.
+This chip as well as various compatible chips support a local and a remote
+temperature sensor with 8 bit accuracy. Later chips provide improved accuracy
+and other additional features such as hysteresis and temperature offset
+registers.
+
+Note that there is no easy way to differentiate between the MAX6657,
+MAX6658 and MAX6659 variants. The extra features of the MAX6659 are only
+supported by this driver if the chip is located at address 0x4d or 0x4e,
+or if the chip type is explicitly selected as max6659.
+The MAX6680 and MAX6681 only differ in their pinout, therefore they obviously
+can't (and don't need to) be distinguished.
+
+The different chipsets of the family are not strictly identical, although
+very similar. For reference, here comes a non-exhaustive list of specific
+features:
+
+LM84:
+  * 8 bit sensor resolution
+
+ADM1020, ADM1021, GL523SM, MAX1617, NE1617, NE1617A, THMC10:
+  * 8 bit sensor resolution
+  * Low temperature limits
+
+NCT210, NE1618:
+  * 11 bit sensor resolution for remote temperature sensor
+  * Low temperature limits
+
+ADM1021A, ADM1023:
+  * Temperature offset register for remote temperature sensor
+  * 11 bit resolution for remote temperature sensor
+  * Low temperature limits
+
+LM90:
+  * 11 bit resolution for remote temperature sensor
+  * Temperature offset register for remote temperature sensor
+  * Low and critical temperature limits
+  * Configurable conversion rate
+  * Filter and alert configuration register at 0xBF.
+  * ALERT is triggered by temperatures over critical limits.
+
+LM86 and LM89:
+  * Same as LM90
+  * Better external channel accuracy
+
+LM99:
+  * Same as LM89
+  * External temperature shifted by 16 degrees down
+
+ADM1032:
+  * Consecutive alert register at 0x22.
+  * Conversion averaging.
+  * Up to 64 conversions/s.
+  * ALERT is triggered by open remote sensor.
+  * SMBus PEC support for Write Byte and Receive Byte transactions.
+
+ADT7461, ADT7461A, NCT1008:
+  * Extended temperature range (breaks compatibility)
+  * Lower resolution for remote temperature
+  * SMBus PEC support for Write Byte and Receive Byte transactions.
+  * 10 bit temperature resolution
+
+ADT7481, ADT7482, ADT7483:
+  * Temperature offset register
+  * SMBus PEC support
+  * 10 bit temperature resolution for external sensors
+  * Two remote sensors
+  * Selectable address (ADT7483)
+
+MAX6642:
+  * No critical limit register
+  * Conversion rate not configurable
+  * Better local resolution (10 bit)
+  * 10 bit external sensor resolution
+
+MAX6646, MAX6647, MAX6649:
+  * Better local resolution
+  * Extended range unsigned external temperature
+
+MAX6648, MAX6692:
+  * Better local resolution
+  * Unsigned temperature
+
+MAX6654, MAX6690:
+  * Better local resolution
+  * Selectable address
+  * Remote sensor type selection
+  * Extended temperature range
+  * Extended resolution only available when conversion rate <= 1 Hz
+
+MAX6657 and MAX6658:
+  * Better local resolution
+  * Remote sensor type selection
+
+MAX6659:
+  * Better local resolution
+  * Selectable address
+  * Second critical temperature limit
+  * Remote sensor type selection
+
+MAX6680 and MAX6681:
+  * Selectable address
+  * Remote sensor type selection
+
+MAX6695 and MAX6696:
+  * Better local resolution
+  * Selectable address (max6696)
+  * Second critical temperature limit
+  * Two remote sensors
+
+W83L771W/G
+  * The G variant is lead-free, otherwise similar to the W.
+  * Filter and alert configuration register at 0xBF
+  * Moving average (depending on conversion rate)
+
+W83L771AWG/ASG
+  * Successor of the W83L771W/G, same features.
+  * The AWG and ASG variants only differ in package format.
+  * Diode ideality factor configuration (remote sensor) at 0xE3
+
+SA56004X:
+  * Better local resolution
+
+All temperature values are given in degrees Celsius. Resolution
+is 1.0 degree for the local temperature, 0.125 degree for the remote
+temperature, except for the MAX6654, MAX6657, MAX6658 and MAX6659 which have
+a resolution of 0.125 degree for both temperatures.
+
+Each sensor has its own high and low limits, plus a critical limit.
+Additionally, there is a relative hysteresis value common to both critical
+values. To make life easier to user-space applications, two absolute values
+are exported, one for each channel, but these values are of course linked.
+Only the local hysteresis can be set from user-space, and the same delta
+applies to the remote hysteresis.
+
+The lm90 driver will not update its values more frequently than configured with
+the update_interval attribute; reading them more often will do no harm, but will
+return 'old' values.
+
+SMBus Alert Support
+-------------------
+
+This driver has basic support for SMBus alert. When an alert is received,
+the status register is read and the faulty temperature channel is logged.
+
+The Analog Devices chips (ADM1032, ADT7461 and ADT7461A) and ON
+Semiconductor chips (NCT1008) do not implement the SMBus alert protocol
+properly so additional care is needed: the ALERT output is disabled when
+an alert is received, and is re-enabled only when the alarm is gone.
+Otherwise the chip would block alerts from other chips in the bus as long
+as the alarm is active.
+
+PEC Support
+-----------
+
+The ADM1032 is the only chip of the family which supports PEC. It does
+not support PEC on all transactions though, so some care must be taken.
+
+When reading a register value, the PEC byte is computed and sent by the
+ADM1032 chip. However, in the case of a combined transaction (SMBus Read
+Byte), the ADM1032 computes the CRC value over only the second half of
+the message rather than its entirety, because it thinks the first half
+of the message belongs to a different transaction. As a result, the CRC
+value differs from what the SMBus master expects, and all reads fail.
+
+For this reason, the lm90 driver will enable PEC for the ADM1032 only if
+the bus supports the SMBus Send Byte and Receive Byte transaction types.
+These transactions will be used to read register values, instead of
+SMBus Read Byte, and PEC will work properly.
+
+Additionally, the ADM1032 doesn't support SMBus Send Byte with PEC.
+Instead, it will try to write the PEC value to the register (because the
+SMBus Send Byte transaction with PEC is similar to a Write Byte transaction
+without PEC), which is not what we want. Thus, PEC is explicitly disabled
+on SMBus Send Byte transactions in the lm90 driver.
+
+PEC on byte data transactions represents a significant increase in bandwidth
+usage (+33% for writes, +25% for reads) in normal conditions. With the need
+to use two SMBus transaction for reads, this overhead jumps to +50%. Worse,
+two transactions will typically mean twice as much delay waiting for
+transaction completion, effectively doubling the register cache refresh time.
+I guess reliability comes at a price, but it's quite expensive this time.
+
+So, as not everyone might enjoy the slowdown, PEC is disabled by default and
+can be enabled through sysfs. Just write 1 to the "pec" file and PEC will be
+enabled. Write 0 to that file to disable PEC again.