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, 565 insertions, 0 deletions

diff --git a/drivers/hwmon/max6621.c b/drivers/hwmon/max6621.c
new file mode 100644
index 000000000..7821132e1
--- /dev/null
+++ b/drivers/hwmon/max6621.c
@@ -0,0 +1,565 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Hardware monitoring driver for Maxim MAX6621
+ *
+ * Copyright (c) 2017 Mellanox Technologies. All rights reserved.
+ * Copyright (c) 2017 Vadim Pasternak <vadimp@mellanox.com>
+ */
+
+#include <linux/bitops.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/regmap.h>
+
+#define MAX6621_DRV_NAME		"max6621"
+#define MAX6621_TEMP_INPUT_REG_NUM	9
+#define MAX6621_TEMP_INPUT_MIN		-127000
+#define MAX6621_TEMP_INPUT_MAX		128000
+#define MAX6621_TEMP_ALERT_CHAN_SHIFT	1
+
+#define MAX6621_TEMP_S0D0_REG		0x00
+#define MAX6621_TEMP_S0D1_REG		0x01
+#define MAX6621_TEMP_S1D0_REG		0x02
+#define MAX6621_TEMP_S1D1_REG		0x03
+#define MAX6621_TEMP_S2D0_REG		0x04
+#define MAX6621_TEMP_S2D1_REG		0x05
+#define MAX6621_TEMP_S3D0_REG		0x06
+#define MAX6621_TEMP_S3D1_REG		0x07
+#define MAX6621_TEMP_MAX_REG		0x08
+#define MAX6621_TEMP_MAX_ADDR_REG	0x0a
+#define MAX6621_TEMP_ALERT_CAUSE_REG	0x0b
+#define MAX6621_CONFIG0_REG		0x0c
+#define MAX6621_CONFIG1_REG		0x0d
+#define MAX6621_CONFIG2_REG		0x0e
+#define MAX6621_CONFIG3_REG		0x0f
+#define MAX6621_TEMP_S0_ALERT_REG	0x10
+#define MAX6621_TEMP_S1_ALERT_REG	0x11
+#define MAX6621_TEMP_S2_ALERT_REG	0x12
+#define MAX6621_TEMP_S3_ALERT_REG	0x13
+#define MAX6621_CLEAR_ALERT_REG		0x15
+#define MAX6621_REG_MAX			(MAX6621_CLEAR_ALERT_REG + 1)
+#define MAX6621_REG_TEMP_SHIFT		0x06
+
+#define MAX6621_ENABLE_TEMP_ALERTS_BIT	4
+#define MAX6621_ENABLE_I2C_CRC_BIT	5
+#define MAX6621_ENABLE_ALTERNATE_DATA	6
+#define MAX6621_ENABLE_LOCKUP_TO	7
+#define MAX6621_ENABLE_S0D0_BIT		8
+#define MAX6621_ENABLE_S3D1_BIT		15
+#define MAX6621_ENABLE_TEMP_ALL		GENMASK(MAX6621_ENABLE_S3D1_BIT, \
+						MAX6621_ENABLE_S0D0_BIT)
+#define MAX6621_POLL_DELAY_MASK		0x5
+#define MAX6621_CONFIG0_INIT		(MAX6621_ENABLE_TEMP_ALL | \
+					 BIT(MAX6621_ENABLE_LOCKUP_TO) | \
+					 BIT(MAX6621_ENABLE_I2C_CRC_BIT) | \
+					 MAX6621_POLL_DELAY_MASK)
+#define MAX6621_PECI_BIT_TIME		0x2
+#define MAX6621_PECI_RETRY_NUM		0x3
+#define MAX6621_CONFIG1_INIT		((MAX6621_PECI_BIT_TIME << 8) | \
+					 MAX6621_PECI_RETRY_NUM)
+
+/* Error codes */
+#define MAX6621_TRAN_FAILED	0x8100	/*
+					 * PECI transaction failed for more
+					 * than the configured number of
+					 * consecutive retries.
+					 */
+#define MAX6621_POOL_DIS	0x8101	/*
+					 * Polling disabled for requested
+					 * socket/domain.
+					 */
+#define MAX6621_POOL_UNCOMPLETE	0x8102	/*
+					 * First poll not yet completed for
+					 * requested socket/domain (on
+					 * startup).
+					 */
+#define MAX6621_SD_DIS		0x8103	/*
+					 * Read maximum temperature requested,
+					 * but no sockets/domains enabled or
+					 * all enabled sockets/domains have
+					 * errors; or read maximum temperature
+					 * address requested, but read maximum
+					 * temperature was not called.
+					 */
+#define MAX6621_ALERT_DIS	0x8104	/*
+					 * Get alert socket/domain requested,
+					 * but no alert active.
+					 */
+#define MAX6621_PECI_ERR_MIN	0x8000	/* Intel spec PECI error min value. */
+#define MAX6621_PECI_ERR_MAX	0x80ff	/* Intel spec PECI error max value. */
+
+static const u32 max6621_temp_regs[] = {
+	MAX6621_TEMP_MAX_REG, MAX6621_TEMP_S0D0_REG, MAX6621_TEMP_S1D0_REG,
+	MAX6621_TEMP_S2D0_REG, MAX6621_TEMP_S3D0_REG, MAX6621_TEMP_S0D1_REG,
+	MAX6621_TEMP_S1D1_REG, MAX6621_TEMP_S2D1_REG, MAX6621_TEMP_S3D1_REG,
+};
+
+static const char *const max6621_temp_labels[] = {
+	"maximum",
+	"socket0_0",
+	"socket1_0",
+	"socket2_0",
+	"socket3_0",
+	"socket0_1",
+	"socket1_1",
+	"socket2_1",
+	"socket3_1",
+};
+
+static const int max6621_temp_alert_chan2reg[] = {
+	MAX6621_TEMP_S0_ALERT_REG,
+	MAX6621_TEMP_S1_ALERT_REG,
+	MAX6621_TEMP_S2_ALERT_REG,
+	MAX6621_TEMP_S3_ALERT_REG,
+};
+
+/**
+ * struct max6621_data - private data:
+ *
+ * @client: I2C client;
+ * @regmap: register map handle;
+ * @input_chan2reg: mapping from channel to register;
+ */
+struct max6621_data {
+	struct i2c_client	*client;
+	struct regmap		*regmap;
+	int			input_chan2reg[MAX6621_TEMP_INPUT_REG_NUM + 1];
+};
+
+static long max6621_temp_mc2reg(long val)
+{
+	return (val / 1000L) << MAX6621_REG_TEMP_SHIFT;
+}
+
+static umode_t
+max6621_is_visible(const void *data, enum hwmon_sensor_types type, u32 attr,
+		   int channel)
+{
+	/* Skip channels which are not physically conncted. */
+	if (((struct max6621_data *)data)->input_chan2reg[channel] < 0)
+		return 0;
+
+	switch (type) {
+	case hwmon_temp:
+		switch (attr) {
+		case hwmon_temp_input:
+		case hwmon_temp_label:
+		case hwmon_temp_crit_alarm:
+			return 0444;
+		case hwmon_temp_offset:
+		case hwmon_temp_crit:
+			return 0644;
+		default:
+			break;
+		}
+		break;
+	default:
+		break;
+	}
+
+	return 0;
+}
+
+static int max6621_verify_reg_data(struct device *dev, int regval)
+{
+	if (regval >= MAX6621_PECI_ERR_MIN &&
+	    regval <= MAX6621_PECI_ERR_MAX) {
+		dev_dbg(dev, "PECI error code - err 0x%04x.\n",
+			regval);
+
+		return -EIO;
+	}
+
+	switch (regval) {
+	case MAX6621_TRAN_FAILED:
+		dev_dbg(dev, "PECI transaction failed - err 0x%04x.\n",
+			regval);
+		return -EIO;
+	case MAX6621_POOL_DIS:
+		dev_dbg(dev, "Polling disabled - err 0x%04x.\n", regval);
+		return -EOPNOTSUPP;
+	case MAX6621_POOL_UNCOMPLETE:
+		dev_dbg(dev, "First poll not completed on startup - err 0x%04x.\n",
+			regval);
+		return -EIO;
+	case MAX6621_SD_DIS:
+		dev_dbg(dev, "Resource is disabled - err 0x%04x.\n", regval);
+		return -EOPNOTSUPP;
+	case MAX6621_ALERT_DIS:
+		dev_dbg(dev, "No alert active - err 0x%04x.\n", regval);
+		return -EOPNOTSUPP;
+	default:
+		return 0;
+	}
+}
+
+static int
+max6621_read(struct device *dev, enum hwmon_sensor_types type, u32 attr,
+	     int channel, long *val)
+{
+	struct max6621_data *data = dev_get_drvdata(dev);
+	u32 regval;
+	int reg;
+	s8 temp;
+	int ret;
+
+	switch (type) {
+	case hwmon_temp:
+		switch (attr) {
+		case hwmon_temp_input:
+			reg = data->input_chan2reg[channel];
+			ret = regmap_read(data->regmap, reg, &regval);
+			if (ret)
+				return ret;
+
+			ret = max6621_verify_reg_data(dev, regval);
+			if (ret)
+				return ret;
+
+			/*
+			 * Bit MAX6621_REG_TEMP_SHIFT represents 1 degree step.
+			 * The temperature is given in two's complement and 8
+			 * bits is used for the register conversion.
+			 */
+			temp = (regval >> MAX6621_REG_TEMP_SHIFT);
+			*val = temp * 1000L;
+
+			break;
+		case hwmon_temp_offset:
+			ret = regmap_read(data->regmap, MAX6621_CONFIG2_REG,
+					  &regval);
+			if (ret)
+				return ret;
+
+			ret = max6621_verify_reg_data(dev, regval);
+			if (ret)
+				return ret;
+
+			*val = (regval >> MAX6621_REG_TEMP_SHIFT) *
+			       1000L;
+
+			break;
+		case hwmon_temp_crit:
+			channel -= MAX6621_TEMP_ALERT_CHAN_SHIFT;
+			reg = max6621_temp_alert_chan2reg[channel];
+			ret = regmap_read(data->regmap, reg, &regval);
+			if (ret)
+				return ret;
+
+			ret = max6621_verify_reg_data(dev, regval);
+			if (ret)
+				return ret;
+
+			*val = regval * 1000L;
+
+			break;
+		case hwmon_temp_crit_alarm:
+			/*
+			 * Set val to zero to recover the case, when reading
+			 * MAX6621_TEMP_ALERT_CAUSE_REG results in for example
+			 * MAX6621_ALERT_DIS. Reading will return with error,
+			 * but in such case alarm should be returned as 0.
+			 */
+			*val = 0;
+			ret = regmap_read(data->regmap,
+					  MAX6621_TEMP_ALERT_CAUSE_REG,
+					  &regval);
+			if (ret)
+				return ret;
+
+			ret = max6621_verify_reg_data(dev, regval);
+			if (ret) {
+				/* Do not report error if alert is disabled. */
+				if (regval == MAX6621_ALERT_DIS)
+					return 0;
+				else
+					return ret;
+			}
+
+			/*
+			 * Clear the alert automatically, using send-byte
+			 * smbus protocol for clearing alert.
+			 */
+			if (regval) {
+				ret = i2c_smbus_write_byte(data->client,
+						MAX6621_CLEAR_ALERT_REG);
+				if (ret)
+					return ret;
+			}
+
+			*val = !!regval;
+
+			break;
+		default:
+			return -EOPNOTSUPP;
+		}
+		break;
+
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	return 0;
+}
+
+static int
+max6621_write(struct device *dev, enum hwmon_sensor_types type, u32 attr,
+	      int channel, long val)
+{
+	struct max6621_data *data = dev_get_drvdata(dev);
+	u32 reg;
+
+	switch (type) {
+	case hwmon_temp:
+		switch (attr) {
+		case hwmon_temp_offset:
+			/* Clamp to allowed range to prevent overflow. */
+			val = clamp_val(val, MAX6621_TEMP_INPUT_MIN,
+					MAX6621_TEMP_INPUT_MAX);
+			val = max6621_temp_mc2reg(val);
+
+			return regmap_write(data->regmap,
+					    MAX6621_CONFIG2_REG, val);
+		case hwmon_temp_crit:
+			channel -= MAX6621_TEMP_ALERT_CHAN_SHIFT;
+			reg = max6621_temp_alert_chan2reg[channel];
+			/* Clamp to allowed range to prevent overflow. */
+			val = clamp_val(val, MAX6621_TEMP_INPUT_MIN,
+					MAX6621_TEMP_INPUT_MAX);
+			val = val / 1000L;
+
+			return regmap_write(data->regmap, reg, val);
+		default:
+			return -EOPNOTSUPP;
+		}
+		break;
+
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	return -EOPNOTSUPP;
+}
+
+static int
+max6621_read_string(struct device *dev, enum hwmon_sensor_types type, u32 attr,
+		    int channel, const char **str)
+{
+	switch (type) {
+	case hwmon_temp:
+		switch (attr) {
+		case hwmon_temp_label:
+			*str = max6621_temp_labels[channel];
+			return 0;
+		default:
+			return -EOPNOTSUPP;
+		}
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	return -EOPNOTSUPP;
+}
+
+static bool max6621_writeable_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case MAX6621_CONFIG0_REG:
+	case MAX6621_CONFIG1_REG:
+	case MAX6621_CONFIG2_REG:
+	case MAX6621_CONFIG3_REG:
+	case MAX6621_TEMP_S0_ALERT_REG:
+	case MAX6621_TEMP_S1_ALERT_REG:
+	case MAX6621_TEMP_S2_ALERT_REG:
+	case MAX6621_TEMP_S3_ALERT_REG:
+	case MAX6621_TEMP_ALERT_CAUSE_REG:
+		return true;
+	}
+	return false;
+}
+
+static bool max6621_readable_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case MAX6621_TEMP_S0D0_REG:
+	case MAX6621_TEMP_S0D1_REG:
+	case MAX6621_TEMP_S1D0_REG:
+	case MAX6621_TEMP_S1D1_REG:
+	case MAX6621_TEMP_S2D0_REG:
+	case MAX6621_TEMP_S2D1_REG:
+	case MAX6621_TEMP_S3D0_REG:
+	case MAX6621_TEMP_S3D1_REG:
+	case MAX6621_TEMP_MAX_REG:
+	case MAX6621_TEMP_MAX_ADDR_REG:
+	case MAX6621_CONFIG0_REG:
+	case MAX6621_CONFIG1_REG:
+	case MAX6621_CONFIG2_REG:
+	case MAX6621_CONFIG3_REG:
+	case MAX6621_TEMP_S0_ALERT_REG:
+	case MAX6621_TEMP_S1_ALERT_REG:
+	case MAX6621_TEMP_S2_ALERT_REG:
+	case MAX6621_TEMP_S3_ALERT_REG:
+		return true;
+	}
+	return false;
+}
+
+static bool max6621_volatile_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case MAX6621_TEMP_S0D0_REG:
+	case MAX6621_TEMP_S0D1_REG:
+	case MAX6621_TEMP_S1D0_REG:
+	case MAX6621_TEMP_S1D1_REG:
+	case MAX6621_TEMP_S2D0_REG:
+	case MAX6621_TEMP_S2D1_REG:
+	case MAX6621_TEMP_S3D0_REG:
+	case MAX6621_TEMP_S3D1_REG:
+	case MAX6621_TEMP_MAX_REG:
+	case MAX6621_TEMP_S0_ALERT_REG:
+	case MAX6621_TEMP_S1_ALERT_REG:
+	case MAX6621_TEMP_S2_ALERT_REG:
+	case MAX6621_TEMP_S3_ALERT_REG:
+	case MAX6621_TEMP_ALERT_CAUSE_REG:
+		return true;
+	}
+	return false;
+}
+
+static const struct reg_default max6621_regmap_default[] = {
+	{ MAX6621_CONFIG0_REG, MAX6621_CONFIG0_INIT },
+	{ MAX6621_CONFIG1_REG, MAX6621_CONFIG1_INIT },
+};
+
+static const struct regmap_config max6621_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 16,
+	.max_register = MAX6621_REG_MAX,
+	.val_format_endian = REGMAP_ENDIAN_LITTLE,
+	.cache_type = REGCACHE_FLAT,
+	.writeable_reg = max6621_writeable_reg,
+	.readable_reg = max6621_readable_reg,
+	.volatile_reg = max6621_volatile_reg,
+	.reg_defaults = max6621_regmap_default,
+	.num_reg_defaults = ARRAY_SIZE(max6621_regmap_default),
+};
+
+static const struct hwmon_channel_info *max6621_info[] = {
+	HWMON_CHANNEL_INFO(chip,
+			   HWMON_C_REGISTER_TZ),
+	HWMON_CHANNEL_INFO(temp,
+			   HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_OFFSET,
+			   HWMON_T_INPUT | HWMON_T_CRIT | HWMON_T_CRIT_ALARM | HWMON_T_LABEL,
+			   HWMON_T_INPUT | HWMON_T_CRIT | HWMON_T_CRIT_ALARM | HWMON_T_LABEL,
+			   HWMON_T_INPUT | HWMON_T_CRIT | HWMON_T_CRIT_ALARM | HWMON_T_LABEL,
+			   HWMON_T_INPUT | HWMON_T_CRIT | HWMON_T_CRIT_ALARM | HWMON_T_LABEL,
+			   HWMON_T_INPUT | HWMON_T_LABEL,
+			   HWMON_T_INPUT | HWMON_T_LABEL,
+			   HWMON_T_INPUT | HWMON_T_LABEL,
+			   HWMON_T_INPUT | HWMON_T_LABEL),
+	NULL
+};
+
+static const struct hwmon_ops max6621_hwmon_ops = {
+	.read = max6621_read,
+	.write = max6621_write,
+	.read_string = max6621_read_string,
+	.is_visible = max6621_is_visible,
+};
+
+static const struct hwmon_chip_info max6621_chip_info = {
+	.ops = &max6621_hwmon_ops,
+	.info = max6621_info,
+};
+
+static int max6621_probe(struct i2c_client *client)
+{
+	struct device *dev = &client->dev;
+	struct max6621_data *data;
+	struct device *hwmon_dev;
+	int i;
+	int ret;
+
+	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->regmap = devm_regmap_init_i2c(client, &max6621_regmap_config);
+	if (IS_ERR(data->regmap))
+		return PTR_ERR(data->regmap);
+
+	i2c_set_clientdata(client, data);
+	data->client = client;
+
+	/* Set CONFIG0 register masking temperature alerts and PEC. */
+	ret = regmap_write(data->regmap, MAX6621_CONFIG0_REG,
+			   MAX6621_CONFIG0_INIT);
+	if (ret)
+		return ret;
+
+	/* Set CONFIG1 register for PEC access retry number. */
+	ret = regmap_write(data->regmap, MAX6621_CONFIG1_REG,
+			   MAX6621_CONFIG1_INIT);
+	if (ret)
+		return ret;
+
+	/* Sync registers with hardware. */
+	regcache_mark_dirty(data->regmap);
+	ret = regcache_sync(data->regmap);
+	if (ret)
+		return ret;
+
+	/* Verify which temperature input registers are enabled. */
+	for (i = 0; i < MAX6621_TEMP_INPUT_REG_NUM; i++) {
+		ret = i2c_smbus_read_word_data(client, max6621_temp_regs[i]);
+		if (ret < 0)
+			return ret;
+		ret = max6621_verify_reg_data(dev, ret);
+		if (ret) {
+			data->input_chan2reg[i] = -1;
+			continue;
+		}
+
+		data->input_chan2reg[i] = max6621_temp_regs[i];
+	}
+
+	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
+							 data,
+							 &max6621_chip_info,
+							 NULL);
+
+	return PTR_ERR_OR_ZERO(hwmon_dev);
+}
+
+static const struct i2c_device_id max6621_id[] = {
+	{ MAX6621_DRV_NAME, 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, max6621_id);
+
+static const struct of_device_id __maybe_unused max6621_of_match[] = {
+	{ .compatible = "maxim,max6621" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, max6621_of_match);
+
+static struct i2c_driver max6621_driver = {
+	.class		= I2C_CLASS_HWMON,
+	.driver = {
+		.name = MAX6621_DRV_NAME,
+		.of_match_table = of_match_ptr(max6621_of_match),
+	},
+	.probe_new	= max6621_probe,
+	.id_table	= max6621_id,
+};
+
+module_i2c_driver(max6621_driver);
+
+MODULE_AUTHOR("Vadim Pasternak <vadimp@mellanox.com>");
+MODULE_DESCRIPTION("Driver for Maxim MAX6621");
+MODULE_LICENSE("GPL");