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, 830 insertions, 0 deletions

diff --git a/drivers/hwmon/max6650.c b/drivers/hwmon/max6650.c
new file mode 100644
index 000000000..f8d4534ce
--- /dev/null
+++ b/drivers/hwmon/max6650.c
@@ -0,0 +1,830 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * max6650.c - Part of lm_sensors, Linux kernel modules for hardware
+ *             monitoring.
+ *
+ * (C) 2007 by Hans J. Koch <hjk@hansjkoch.de>
+ *
+ * based on code written by John Morris <john.morris@spirentcom.com>
+ * Copyright (c) 2003 Spirent Communications
+ * and Claus Gindhart <claus.gindhart@kontron.com>
+ *
+ * This module has only been tested with the MAX6650 chip. It should
+ * also work with the MAX6651. It does not distinguish max6650 and max6651
+ * chips.
+ *
+ * The datasheet was last seen at:
+ *
+ *        http://pdfserv.maxim-ic.com/en/ds/MAX6650-MAX6651.pdf
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/jiffies.h>
+#include <linux/i2c.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/err.h>
+#include <linux/of_device.h>
+#include <linux/thermal.h>
+
+/*
+ * Insmod parameters
+ */
+
+/* fan_voltage: 5=5V fan, 12=12V fan, 0=don't change */
+static int fan_voltage;
+/* prescaler: Possible values are 1, 2, 4, 8, 16 or 0 for don't change */
+static int prescaler;
+/* clock: The clock frequency of the chip (max6651 can be clocked externally) */
+static int clock = 254000;
+
+module_param(fan_voltage, int, 0444);
+module_param(prescaler, int, 0444);
+module_param(clock, int, 0444);
+
+/*
+ * MAX 6650/6651 registers
+ */
+
+#define MAX6650_REG_SPEED	0x00
+#define MAX6650_REG_CONFIG	0x02
+#define MAX6650_REG_GPIO_DEF	0x04
+#define MAX6650_REG_DAC		0x06
+#define MAX6650_REG_ALARM_EN	0x08
+#define MAX6650_REG_ALARM	0x0A
+#define MAX6650_REG_TACH0	0x0C
+#define MAX6650_REG_TACH1	0x0E
+#define MAX6650_REG_TACH2	0x10
+#define MAX6650_REG_TACH3	0x12
+#define MAX6650_REG_GPIO_STAT	0x14
+#define MAX6650_REG_COUNT	0x16
+
+/*
+ * Config register bits
+ */
+
+#define MAX6650_CFG_V12			0x08
+#define MAX6650_CFG_PRESCALER_MASK	0x07
+#define MAX6650_CFG_PRESCALER_2		0x01
+#define MAX6650_CFG_PRESCALER_4		0x02
+#define MAX6650_CFG_PRESCALER_8		0x03
+#define MAX6650_CFG_PRESCALER_16	0x04
+#define MAX6650_CFG_MODE_MASK		0x30
+#define MAX6650_CFG_MODE_ON		0x00
+#define MAX6650_CFG_MODE_OFF		0x10
+#define MAX6650_CFG_MODE_CLOSED_LOOP	0x20
+#define MAX6650_CFG_MODE_OPEN_LOOP	0x30
+#define MAX6650_COUNT_MASK		0x03
+
+/*
+ * Alarm status register bits
+ */
+
+#define MAX6650_ALRM_MAX	0x01
+#define MAX6650_ALRM_MIN	0x02
+#define MAX6650_ALRM_TACH	0x04
+#define MAX6650_ALRM_GPIO1	0x08
+#define MAX6650_ALRM_GPIO2	0x10
+
+/* Minimum and maximum values of the FAN-RPM */
+#define FAN_RPM_MIN 240
+#define FAN_RPM_MAX 30000
+
+#define DIV_FROM_REG(reg)	(1 << ((reg) & 7))
+#define DAC_LIMIT(v12)		((v12) ? 180 : 76)
+
+/*
+ * Client data (each client gets its own)
+ */
+
+struct max6650_data {
+	struct i2c_client *client;
+	struct mutex update_lock; /* protect alarm register updates */
+	int nr_fans;
+	bool valid; /* false until following fields are valid */
+	unsigned long last_updated; /* in jiffies */
+
+	/* register values */
+	u8 speed;
+	u8 config;
+	u8 tach[4];
+	u8 count;
+	u8 dac;
+	u8 alarm;
+	u8 alarm_en;
+	unsigned long cooling_dev_state;
+};
+
+static const u8 tach_reg[] = {
+	MAX6650_REG_TACH0,
+	MAX6650_REG_TACH1,
+	MAX6650_REG_TACH2,
+	MAX6650_REG_TACH3,
+};
+
+static const struct of_device_id __maybe_unused max6650_dt_match[] = {
+	{
+		.compatible = "maxim,max6650",
+		.data = (void *)1
+	},
+	{
+		.compatible = "maxim,max6651",
+		.data = (void *)4
+	},
+	{ },
+};
+MODULE_DEVICE_TABLE(of, max6650_dt_match);
+
+static int dac_to_pwm(int dac, bool v12)
+{
+	/*
+	 * Useful range for dac is 0-180 for 12V fans and 0-76 for 5V fans.
+	 * Lower DAC values mean higher speeds.
+	 */
+	return clamp_val(255 - (255 * dac) / DAC_LIMIT(v12), 0, 255);
+}
+
+static u8 pwm_to_dac(unsigned int pwm, bool v12)
+{
+	int limit = DAC_LIMIT(v12);
+
+	return limit - (limit * pwm) / 255;
+}
+
+static struct max6650_data *max6650_update_device(struct device *dev)
+{
+	struct max6650_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
+	int reg, err = 0;
+	int i;
+
+	mutex_lock(&data->update_lock);
+
+	if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
+		for (i = 0; i < data->nr_fans; i++) {
+			reg = i2c_smbus_read_byte_data(client, tach_reg[i]);
+			if (reg < 0) {
+				err = reg;
+				goto error;
+			}
+			data->tach[i] = reg;
+		}
+
+		/*
+		 * Alarms are cleared on read in case the condition that
+		 * caused the alarm is removed. Keep the value latched here
+		 * for providing the register through different alarm files.
+		 */
+		reg = i2c_smbus_read_byte_data(client, MAX6650_REG_ALARM);
+		if (reg < 0) {
+			err = reg;
+			goto error;
+		}
+		data->alarm |= reg;
+		data->last_updated = jiffies;
+		data->valid = true;
+	}
+
+error:
+	mutex_unlock(&data->update_lock);
+	if (err)
+		data = ERR_PTR(err);
+	return data;
+}
+
+/*
+ * Change the operating mode of the chip (if needed).
+ * mode is one of the MAX6650_CFG_MODE_* values.
+ */
+static int max6650_set_operating_mode(struct max6650_data *data, u8 mode)
+{
+	int result;
+	u8 config = data->config;
+
+	if (mode == (config & MAX6650_CFG_MODE_MASK))
+		return 0;
+
+	config = (config & ~MAX6650_CFG_MODE_MASK) | mode;
+
+	result = i2c_smbus_write_byte_data(data->client, MAX6650_REG_CONFIG,
+					   config);
+	if (result < 0)
+		return result;
+
+	data->config = config;
+
+	return 0;
+}
+
+/*
+ * Set the fan speed to the specified RPM (or read back the RPM setting).
+ * This works in closed loop mode only. Use pwm1 for open loop speed setting.
+ *
+ * The MAX6650/1 will automatically control fan speed when in closed loop
+ * mode.
+ *
+ * Assumptions:
+ *
+ * 1) The MAX6650/1 internal 254kHz clock frequency is set correctly. Use
+ *    the clock module parameter if you need to fine tune this.
+ *
+ * 2) The prescaler (low three bits of the config register) has already
+ *    been set to an appropriate value. Use the prescaler module parameter
+ *    if your BIOS doesn't initialize the chip properly.
+ *
+ * The relevant equations are given on pages 21 and 22 of the datasheet.
+ *
+ * From the datasheet, the relevant equation when in regulation is:
+ *
+ *    [fCLK / (128 x (KTACH + 1))] = 2 x FanSpeed / KSCALE
+ *
+ * where:
+ *
+ *    fCLK is the oscillator frequency (either the 254kHz internal
+ *         oscillator or the externally applied clock)
+ *
+ *    KTACH is the value in the speed register
+ *
+ *    FanSpeed is the speed of the fan in rps
+ *
+ *    KSCALE is the prescaler value (1, 2, 4, 8, or 16)
+ *
+ * When reading, we need to solve for FanSpeed. When writing, we need to
+ * solve for KTACH.
+ *
+ * Note: this tachometer is completely separate from the tachometers
+ * used to measure the fan speeds. Only one fan's speed (fan1) is
+ * controlled.
+ */
+
+static int max6650_set_target(struct max6650_data *data, unsigned long rpm)
+{
+	int kscale, ktach;
+
+	if (rpm == 0)
+		return max6650_set_operating_mode(data, MAX6650_CFG_MODE_OFF);
+
+	rpm = clamp_val(rpm, FAN_RPM_MIN, FAN_RPM_MAX);
+
+	/*
+	 * Divide the required speed by 60 to get from rpm to rps, then
+	 * use the datasheet equation:
+	 *
+	 *     KTACH = [(fCLK x KSCALE) / (256 x FanSpeed)] - 1
+	 */
+
+	kscale = DIV_FROM_REG(data->config);
+	ktach = ((clock * kscale) / (256 * rpm / 60)) - 1;
+	if (ktach < 0)
+		ktach = 0;
+	if (ktach > 255)
+		ktach = 255;
+	data->speed = ktach;
+
+	return i2c_smbus_write_byte_data(data->client, MAX6650_REG_SPEED,
+					 data->speed);
+}
+
+/*
+ * Get gpio alarm status:
+ * Possible values:
+ * 0 = no alarm
+ * 1 = alarm
+ */
+
+static ssize_t alarm_show(struct device *dev,
+			  struct device_attribute *devattr, char *buf)
+{
+	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+	struct max6650_data *data = max6650_update_device(dev);
+	bool alarm;
+
+	if (IS_ERR(data))
+		return PTR_ERR(data);
+
+	alarm = data->alarm & attr->index;
+	if (alarm) {
+		mutex_lock(&data->update_lock);
+		data->alarm &= ~attr->index;
+		data->valid = false;
+		mutex_unlock(&data->update_lock);
+	}
+
+	return sprintf(buf, "%d\n", alarm);
+}
+
+static SENSOR_DEVICE_ATTR_RO(gpio1_alarm, alarm, MAX6650_ALRM_GPIO1);
+static SENSOR_DEVICE_ATTR_RO(gpio2_alarm, alarm, MAX6650_ALRM_GPIO2);
+
+static umode_t max6650_attrs_visible(struct kobject *kobj, struct attribute *a,
+				     int n)
+{
+	struct device *dev = kobj_to_dev(kobj);
+	struct max6650_data *data = dev_get_drvdata(dev);
+	struct device_attribute *devattr;
+
+	/*
+	 * Hide the alarms that have not been enabled by the firmware
+	 */
+
+	devattr = container_of(a, struct device_attribute, attr);
+	if (devattr == &sensor_dev_attr_gpio1_alarm.dev_attr ||
+	    devattr == &sensor_dev_attr_gpio2_alarm.dev_attr) {
+		if (!(data->alarm_en & to_sensor_dev_attr(devattr)->index))
+			return 0;
+	}
+
+	return a->mode;
+}
+
+static struct attribute *max6650_attrs[] = {
+	&sensor_dev_attr_gpio1_alarm.dev_attr.attr,
+	&sensor_dev_attr_gpio2_alarm.dev_attr.attr,
+	NULL
+};
+
+static const struct attribute_group max6650_group = {
+	.attrs = max6650_attrs,
+	.is_visible = max6650_attrs_visible,
+};
+
+static const struct attribute_group *max6650_groups[] = {
+	&max6650_group,
+	NULL
+};
+
+static int max6650_init_client(struct max6650_data *data,
+			       struct i2c_client *client)
+{
+	struct device *dev = &client->dev;
+	int reg;
+	int err;
+	u32 voltage;
+	u32 prescale;
+	u32 target_rpm;
+
+	if (of_property_read_u32(dev->of_node, "maxim,fan-microvolt",
+				 &voltage))
+		voltage = fan_voltage;
+	else
+		voltage /= 1000000; /* Microvolts to volts */
+	if (of_property_read_u32(dev->of_node, "maxim,fan-prescale",
+				 &prescale))
+		prescale = prescaler;
+
+	reg = i2c_smbus_read_byte_data(client, MAX6650_REG_CONFIG);
+	if (reg < 0) {
+		dev_err(dev, "Error reading config register, aborting.\n");
+		return reg;
+	}
+
+	switch (voltage) {
+	case 0:
+		break;
+	case 5:
+		reg &= ~MAX6650_CFG_V12;
+		break;
+	case 12:
+		reg |= MAX6650_CFG_V12;
+		break;
+	default:
+		dev_err(dev, "illegal value for fan_voltage (%d)\n", voltage);
+	}
+
+	switch (prescale) {
+	case 0:
+		break;
+	case 1:
+		reg &= ~MAX6650_CFG_PRESCALER_MASK;
+		break;
+	case 2:
+		reg = (reg & ~MAX6650_CFG_PRESCALER_MASK)
+			 | MAX6650_CFG_PRESCALER_2;
+		break;
+	case  4:
+		reg = (reg & ~MAX6650_CFG_PRESCALER_MASK)
+			 | MAX6650_CFG_PRESCALER_4;
+		break;
+	case  8:
+		reg = (reg & ~MAX6650_CFG_PRESCALER_MASK)
+			 | MAX6650_CFG_PRESCALER_8;
+		break;
+	case 16:
+		reg = (reg & ~MAX6650_CFG_PRESCALER_MASK)
+			 | MAX6650_CFG_PRESCALER_16;
+		break;
+	default:
+		dev_err(dev, "illegal value for prescaler (%d)\n", prescale);
+	}
+
+	dev_info(dev, "Fan voltage: %dV, prescaler: %d.\n",
+		 (reg & MAX6650_CFG_V12) ? 12 : 5,
+		 1 << (reg & MAX6650_CFG_PRESCALER_MASK));
+
+	err = i2c_smbus_write_byte_data(client, MAX6650_REG_CONFIG, reg);
+	if (err) {
+		dev_err(dev, "Config write error, aborting.\n");
+		return err;
+	}
+	data->config = reg;
+
+	reg = i2c_smbus_read_byte_data(client, MAX6650_REG_SPEED);
+	if (reg < 0) {
+		dev_err(dev, "Failed to read speed register, aborting.\n");
+		return reg;
+	}
+	data->speed = reg;
+
+	reg = i2c_smbus_read_byte_data(client, MAX6650_REG_DAC);
+	if (reg < 0) {
+		dev_err(dev, "Failed to read DAC register, aborting.\n");
+		return reg;
+	}
+	data->dac = reg;
+
+	reg = i2c_smbus_read_byte_data(client, MAX6650_REG_COUNT);
+	if (reg < 0) {
+		dev_err(dev, "Failed to read count register, aborting.\n");
+		return reg;
+	}
+	data->count = reg;
+
+	reg = i2c_smbus_read_byte_data(client, MAX6650_REG_ALARM_EN);
+	if (reg < 0) {
+		dev_err(dev, "Failed to read alarm configuration, aborting.\n");
+		return reg;
+	}
+	data->alarm_en = reg;
+
+	if (!of_property_read_u32(client->dev.of_node, "maxim,fan-target-rpm",
+				  &target_rpm)) {
+		max6650_set_target(data, target_rpm);
+		max6650_set_operating_mode(data, MAX6650_CFG_MODE_CLOSED_LOOP);
+	}
+
+	return 0;
+}
+
+static int max6650_get_max_state(struct thermal_cooling_device *cdev,
+				 unsigned long *state)
+{
+	*state = 255;
+
+	return 0;
+}
+
+static int max6650_get_cur_state(struct thermal_cooling_device *cdev,
+				 unsigned long *state)
+{
+	struct max6650_data *data = cdev->devdata;
+
+	*state = data->cooling_dev_state;
+
+	return 0;
+}
+
+static int max6650_set_cur_state(struct thermal_cooling_device *cdev,
+				 unsigned long state)
+{
+	struct max6650_data *data = cdev->devdata;
+	struct i2c_client *client = data->client;
+	int err;
+
+	state = clamp_val(state, 0, 255);
+
+	mutex_lock(&data->update_lock);
+
+	data->dac = pwm_to_dac(state, data->config & MAX6650_CFG_V12);
+	err = i2c_smbus_write_byte_data(client, MAX6650_REG_DAC, data->dac);
+	if (!err) {
+		max6650_set_operating_mode(data, state ?
+					   MAX6650_CFG_MODE_OPEN_LOOP :
+					   MAX6650_CFG_MODE_OFF);
+		data->cooling_dev_state = state;
+	}
+
+	mutex_unlock(&data->update_lock);
+
+	return err;
+}
+
+static const struct thermal_cooling_device_ops max6650_cooling_ops = {
+	.get_max_state = max6650_get_max_state,
+	.get_cur_state = max6650_get_cur_state,
+	.set_cur_state = max6650_set_cur_state,
+};
+
+static int max6650_read(struct device *dev, enum hwmon_sensor_types type,
+			u32 attr, int channel, long *val)
+{
+	struct max6650_data *data = max6650_update_device(dev);
+	int mode;
+
+	if (IS_ERR(data))
+		return PTR_ERR(data);
+
+	switch (type) {
+	case hwmon_pwm:
+		switch (attr) {
+		case hwmon_pwm_input:
+			*val = dac_to_pwm(data->dac,
+					  data->config & MAX6650_CFG_V12);
+			break;
+		case hwmon_pwm_enable:
+			/*
+			 * Possible values:
+			 * 0 = Fan always on
+			 * 1 = Open loop, Voltage is set according to speed,
+			 *     not regulated.
+			 * 2 = Closed loop, RPM for all fans regulated by fan1
+			 *     tachometer
+			 * 3 = Fan off
+			 */
+			mode = (data->config & MAX6650_CFG_MODE_MASK) >> 4;
+			*val = (4 - mode) & 3; /* {0 1 2 3} -> {0 3 2 1} */
+			break;
+		default:
+			return -EOPNOTSUPP;
+		}
+		break;
+	case hwmon_fan:
+		switch (attr) {
+		case hwmon_fan_input:
+			/*
+			 * Calculation details:
+			 *
+			 * Each tachometer counts over an interval given by the
+			 * "count" register (0.25, 0.5, 1 or 2 seconds).
+			 * The driver assumes that the fans produce two pulses
+			 * per revolution (this seems to be the most common).
+			 */
+			*val = DIV_ROUND_CLOSEST(data->tach[channel] * 120,
+						 DIV_FROM_REG(data->count));
+			break;
+		case hwmon_fan_div:
+			*val = DIV_FROM_REG(data->count);
+			break;
+		case hwmon_fan_target:
+			/*
+			 * Use the datasheet equation:
+			 *    FanSpeed = KSCALE x fCLK / [256 x (KTACH + 1)]
+			 * then multiply by 60 to give rpm.
+			 */
+			*val = 60 * DIV_FROM_REG(data->config) * clock /
+				(256 * (data->speed + 1));
+			break;
+		case hwmon_fan_min_alarm:
+			*val = !!(data->alarm & MAX6650_ALRM_MIN);
+			data->alarm &= ~MAX6650_ALRM_MIN;
+			data->valid = false;
+			break;
+		case hwmon_fan_max_alarm:
+			*val = !!(data->alarm & MAX6650_ALRM_MAX);
+			data->alarm &= ~MAX6650_ALRM_MAX;
+			data->valid = false;
+			break;
+		case hwmon_fan_fault:
+			*val = !!(data->alarm & MAX6650_ALRM_TACH);
+			data->alarm &= ~MAX6650_ALRM_TACH;
+			data->valid = false;
+			break;
+		default:
+			return -EOPNOTSUPP;
+		}
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+	return 0;
+}
+
+static const u8 max6650_pwm_modes[] = {
+	MAX6650_CFG_MODE_ON,
+	MAX6650_CFG_MODE_OPEN_LOOP,
+	MAX6650_CFG_MODE_CLOSED_LOOP,
+	MAX6650_CFG_MODE_OFF,
+};
+
+static int max6650_write(struct device *dev, enum hwmon_sensor_types type,
+			 u32 attr, int channel, long val)
+{
+	struct max6650_data *data = dev_get_drvdata(dev);
+	int ret = 0;
+	u8 reg;
+
+	mutex_lock(&data->update_lock);
+
+	switch (type) {
+	case hwmon_pwm:
+		switch (attr) {
+		case hwmon_pwm_input:
+			reg = pwm_to_dac(clamp_val(val, 0, 255),
+					 data->config & MAX6650_CFG_V12);
+			ret = i2c_smbus_write_byte_data(data->client,
+							MAX6650_REG_DAC, reg);
+			if (ret)
+				break;
+			data->dac = reg;
+			break;
+		case hwmon_pwm_enable:
+			if (val < 0 || val >= ARRAY_SIZE(max6650_pwm_modes)) {
+				ret = -EINVAL;
+				break;
+			}
+			ret = max6650_set_operating_mode(data,
+						max6650_pwm_modes[val]);
+			break;
+		default:
+			ret = -EOPNOTSUPP;
+			break;
+		}
+		break;
+	case hwmon_fan:
+		switch (attr) {
+		case hwmon_fan_div:
+			switch (val) {
+			case 1:
+				reg = 0;
+				break;
+			case 2:
+				reg = 1;
+				break;
+			case 4:
+				reg = 2;
+				break;
+			case 8:
+				reg = 3;
+				break;
+			default:
+				ret = -EINVAL;
+				goto error;
+			}
+			ret = i2c_smbus_write_byte_data(data->client,
+							MAX6650_REG_COUNT, reg);
+			if (ret)
+				break;
+			data->count = reg;
+			break;
+		case hwmon_fan_target:
+			if (val < 0) {
+				ret = -EINVAL;
+				break;
+			}
+			ret = max6650_set_target(data, val);
+			break;
+		default:
+			ret = -EOPNOTSUPP;
+			break;
+		}
+		break;
+	default:
+		ret = -EOPNOTSUPP;
+		break;
+	}
+
+error:
+	mutex_unlock(&data->update_lock);
+	return ret;
+}
+
+static umode_t max6650_is_visible(const void *_data,
+				  enum hwmon_sensor_types type, u32 attr,
+				  int channel)
+{
+	const struct max6650_data *data = _data;
+
+	if (channel && (channel >= data->nr_fans || type != hwmon_fan))
+		return 0;
+
+	switch (type) {
+	case hwmon_fan:
+		switch (attr) {
+		case hwmon_fan_input:
+			return 0444;
+		case hwmon_fan_target:
+		case hwmon_fan_div:
+			return 0644;
+		case hwmon_fan_min_alarm:
+			if (data->alarm_en & MAX6650_ALRM_MIN)
+				return 0444;
+			break;
+		case hwmon_fan_max_alarm:
+			if (data->alarm_en & MAX6650_ALRM_MAX)
+				return 0444;
+			break;
+		case hwmon_fan_fault:
+			if (data->alarm_en & MAX6650_ALRM_TACH)
+				return 0444;
+			break;
+		default:
+			break;
+		}
+		break;
+	case hwmon_pwm:
+		switch (attr) {
+		case hwmon_pwm_input:
+		case hwmon_pwm_enable:
+			return 0644;
+		default:
+			break;
+		}
+		break;
+	default:
+		break;
+	}
+	return 0;
+}
+
+static const struct hwmon_channel_info *max6650_info[] = {
+	HWMON_CHANNEL_INFO(fan, HWMON_F_INPUT | HWMON_F_TARGET | HWMON_F_DIV |
+			   HWMON_F_MIN_ALARM | HWMON_F_MAX_ALARM |
+			   HWMON_F_FAULT,
+			   HWMON_F_INPUT, HWMON_F_INPUT, HWMON_F_INPUT),
+	HWMON_CHANNEL_INFO(pwm, HWMON_PWM_INPUT | HWMON_PWM_ENABLE),
+	NULL
+};
+
+static const struct hwmon_ops max6650_hwmon_ops = {
+	.read = max6650_read,
+	.write = max6650_write,
+	.is_visible = max6650_is_visible,
+};
+
+static const struct hwmon_chip_info max6650_chip_info = {
+	.ops = &max6650_hwmon_ops,
+	.info = max6650_info,
+};
+
+static const struct i2c_device_id max6650_id[];
+
+static int max6650_probe(struct i2c_client *client)
+{
+	struct thermal_cooling_device *cooling_dev;
+	struct device *dev = &client->dev;
+	const struct of_device_id *of_id =
+		of_match_device(of_match_ptr(max6650_dt_match), dev);
+	struct max6650_data *data;
+	struct device *hwmon_dev;
+	int err;
+
+	data = devm_kzalloc(dev, sizeof(struct max6650_data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->client = client;
+	i2c_set_clientdata(client, data);
+	mutex_init(&data->update_lock);
+	data->nr_fans = of_id ? (int)(uintptr_t)of_id->data :
+				i2c_match_id(max6650_id, client)->driver_data;
+
+	/*
+	 * Initialize the max6650 chip
+	 */
+	err = max6650_init_client(data, client);
+	if (err)
+		return err;
+
+	hwmon_dev = devm_hwmon_device_register_with_info(dev,
+							 client->name, data,
+							 &max6650_chip_info,
+							 max6650_groups);
+	err = PTR_ERR_OR_ZERO(hwmon_dev);
+	if (err)
+		return err;
+
+	if (IS_ENABLED(CONFIG_THERMAL)) {
+		cooling_dev = devm_thermal_of_cooling_device_register(dev,
+						dev->of_node, client->name,
+						data, &max6650_cooling_ops);
+		if (IS_ERR(cooling_dev)) {
+			dev_warn(dev, "thermal cooling device register failed: %ld\n",
+				 PTR_ERR(cooling_dev));
+		}
+	}
+
+	return 0;
+}
+
+static const struct i2c_device_id max6650_id[] = {
+	{ "max6650", 1 },
+	{ "max6651", 4 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, max6650_id);
+
+static struct i2c_driver max6650_driver = {
+	.driver = {
+		.name	= "max6650",
+		.of_match_table = of_match_ptr(max6650_dt_match),
+	},
+	.probe_new	= max6650_probe,
+	.id_table	= max6650_id,
+};
+
+module_i2c_driver(max6650_driver);
+
+MODULE_AUTHOR("Hans J. Koch");
+MODULE_DESCRIPTION("MAX6650 sensor driver");
+MODULE_LICENSE("GPL");