Merge tag 'hwmon-for-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging

Pull hwmon updates from Guenter Roeck:
 "Infrastructure:
   - Add notification support

  New drivers:
   - Baikal-T1 PVT sensor driver
   - amd_energy driver to report energy counters
   - Driver for Maxim MAX16601
   - Gateworks System Controller

  Various:
   - applesmc: avoid overlong udelay()
   - dell-smm: Use one DMI match for all XPS models
   - ina2xx: Implement alert functions
   - lm70: Add support for ACPI
   - lm75: Fix coding-style warnings
   - lm90: Add max6654 support to lm90 driver
   - nct7802: Replace container_of() API
   - nct7904: Set default timeout
   - nct7904: Add watchdog function
   - pmbus: Improve initialization of 'currpage' and 'currphase'"

* tag 'hwmon-for-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging: (24 commits)
  hwmon: Add Baikal-T1 PVT sensor driver
  hwmon: Add notification support
  dt-bindings: hwmon: Add Baikal-T1 PVT sensor binding
  hwmon: (applesmc) avoid overlong udelay()
  hwmon: (nct7904) Set default timeout
  hwmon: (amd_energy) Missing platform_driver_unregister() on error in amd_energy_init()
  MAINTAINERS: add entry for AMD energy driver
  hwmon: (amd_energy) Add documentation
  hwmon: Add amd_energy driver to report energy counters
  hwmon: (nct7802) Replace container_of() API
  hwmon: (lm90) Add max6654 support to lm90 driver
  hwmon : (nct6775) Use kobj_to_dev() API
  hwmon: (pmbus) Driver for Maxim MAX16601
  hwmon: (pmbus) Improve initialization of 'currpage' and 'currphase'
  hwmon: (adt7411) update contact email
  hwmon: (lm75) Fix all coding-style warnings on lm75 driver
  hwmon: Reduce indentation level in __hwmon_device_register()
  hwmon: (ina2xx) Implement alert functions
  hwmon: (lm70) Add support for ACPI
  hwmon: (dell-smm) Use one DMI match for all XPS models
  ...

25 files changed, 3416 insertions, 104 deletions

diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 4c62f900bf7e..288ae9f63588 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -324,6 +324,16 @@ config SENSORS_FAM15H_POWER
 	  This driver can also be built as a module. If so, the module
 	  will be called fam15h_power.
 
+config SENSORS_AMD_ENERGY
+	tristate "AMD RAPL MSR based Energy driver"
+	depends on X86
+	help
+	  If you say yes here you get support for core and package energy
+	  sensors, based on RAPL MSR for AMD family 17h and above CPUs.
+
+	  This driver can also be built as a module. If so, the module
+	  will be called as amd_energy.
+
 config SENSORS_APPLESMC
 	tristate "Apple SMC (Motion sensor, light sensor, keyboard backlight)"
 	depends on INPUT && X86
@@ -404,6 +414,31 @@ config SENSORS_ATXP1
 	  This driver can also be built as a module. If so, the module
 	  will be called atxp1.
 
+config SENSORS_BT1_PVT
+	tristate "Baikal-T1 Process, Voltage, Temperature sensor driver"
+	depends on MIPS_BAIKAL_T1 || COMPILE_TEST
+	help
+	  If you say yes here you get support for Baikal-T1 PVT sensor
+	  embedded into the SoC.
+
+	  This driver can also be built as a module. If so, the module will be
+	  called bt1-pvt.
+
+config SENSORS_BT1_PVT_ALARMS
+	bool "Enable Baikal-T1 PVT sensor alarms"
+	depends on SENSORS_BT1_PVT
+	help
+	  Baikal-T1 PVT IP-block provides threshold registers for each
+	  supported sensor. But the corresponding interrupts might be
+	  generated by the thresholds comparator only in synchronization with
+	  a data conversion. Additionally there is only one sensor data can
+	  be converted at a time. All of these makes the interface impossible
+	  to be used for the hwmon alarms implementation without periodic
+	  switch between the PVT sensors. By default the data conversion is
+	  performed on demand from the user-space. If this config is enabled
+	  the data conversion will be periodically performed and the data will be
+	  saved in the internal driver cache.
+
 config SENSORS_DRIVETEMP
 	tristate "Hard disk drives with temperature sensors"
 	depends on SCSI && ATA
@@ -523,6 +558,15 @@ config SENSORS_F75375S
 	  This driver can also be built as a module. If so, the module
 	  will be called f75375s.
 
+config SENSORS_GSC
+	tristate "Gateworks System Controller ADC"
+	depends on MFD_GATEWORKS_GSC
+	help
+	  Support for the Gateworks System Controller A/D converters.
+
+	  To compile this driver as a module, choose M here:
+	  the module will be called gsc-hwmon.
+
 config SENSORS_MC13783_ADC
         tristate "Freescale MC13783/MC13892 ADC"
         depends on MFD_MC13XXX
@@ -1198,10 +1242,11 @@ config SENSORS_LM90
 	help
 	  If you say yes here you get support for National Semiconductor LM90,
 	  LM86, LM89 and LM99, Analog Devices ADM1032, ADT7461, and ADT7461A,
-	  Maxim MAX6646, MAX6647, MAX6648, MAX6649, MAX6657, MAX6658, MAX6659,
-	  MAX6680, MAX6681, MAX6692, MAX6695, MAX6696, ON Semiconductor NCT1008,
-	  Winbond/Nuvoton W83L771W/G/AWG/ASG, Philips SA56004, GMT G781, and
-	  Texas Instruments TMP451 sensor chips.
+	  Maxim MAX6646, MAX6647, MAX6648, MAX6649, MAX6654, MAX6657, MAX6658,
+	  MAX6659, MAX6680, MAX6681, MAX6692, MAX6695, MAX6696,
+	  ON Semiconductor NCT1008, Winbond/Nuvoton W83L771W/G/AWG/ASG,
+	  Philips SA56004, GMT G781, and Texas Instruments TMP451
+	  sensor chips.
 
 	  This driver can also be built as a module. If so, the module
 	  will be called lm90.
@@ -1340,10 +1385,12 @@ config SENSORS_NCT7802
 
 config SENSORS_NCT7904
 	tristate "Nuvoton NCT7904"
-	depends on I2C
+	depends on I2C && WATCHDOG
+	select WATCHDOG_CORE
 	help
 	  If you say yes here you get support for the Nuvoton NCT7904
-	  hardware monitoring chip, including manual fan speed control.
+	  hardware monitoring chip, including manual fan speed control
+	  and support for the integrated watchdog.
 
 	  This driver can also be built as a module. If so, the module
 	  will be called nct7904.
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index b0b9c8e57176..3e32c21f5efe 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -45,6 +45,7 @@ obj-$(CONFIG_SENSORS_ADT7411)	+= adt7411.o
 obj-$(CONFIG_SENSORS_ADT7462)	+= adt7462.o
 obj-$(CONFIG_SENSORS_ADT7470)	+= adt7470.o
 obj-$(CONFIG_SENSORS_ADT7475)	+= adt7475.o
+obj-$(CONFIG_SENSORS_AMD_ENERGY) += amd_energy.o
 obj-$(CONFIG_SENSORS_APPLESMC)	+= applesmc.o
 obj-$(CONFIG_SENSORS_ARM_SCMI)	+= scmi-hwmon.o
 obj-$(CONFIG_SENSORS_ARM_SCPI)	+= scpi-hwmon.o
@@ -53,6 +54,7 @@ obj-$(CONFIG_SENSORS_ASC7621)	+= asc7621.o
 obj-$(CONFIG_SENSORS_ASPEED)	+= aspeed-pwm-tacho.o
 obj-$(CONFIG_SENSORS_ATXP1)	+= atxp1.o
 obj-$(CONFIG_SENSORS_AXI_FAN_CONTROL) += axi-fan-control.o
+obj-$(CONFIG_SENSORS_BT1_PVT)	+= bt1-pvt.o
 obj-$(CONFIG_SENSORS_CORETEMP)	+= coretemp.o
 obj-$(CONFIG_SENSORS_DA9052_ADC)+= da9052-hwmon.o
 obj-$(CONFIG_SENSORS_DA9055)+= da9055-hwmon.o
@@ -74,6 +76,7 @@ obj-$(CONFIG_SENSORS_G760A)	+= g760a.o
 obj-$(CONFIG_SENSORS_G762)	+= g762.o
 obj-$(CONFIG_SENSORS_GL518SM)	+= gl518sm.o
 obj-$(CONFIG_SENSORS_GL520SM)	+= gl520sm.o
+obj-$(CONFIG_SENSORS_GSC)	+= gsc-hwmon.o
 obj-$(CONFIG_SENSORS_GPIO_FAN)	+= gpio-fan.o
 obj-$(CONFIG_SENSORS_HIH6130)	+= hih6130.o
 obj-$(CONFIG_SENSORS_ULTRA45)	+= ultra45_env.o
diff --git a/drivers/hwmon/adt7411.c b/drivers/hwmon/adt7411.c
index c7010b91bc13..5a839cc2ed1c 100644
--- a/drivers/hwmon/adt7411.c
+++ b/drivers/hwmon/adt7411.c
@@ -716,7 +716,6 @@ static struct i2c_driver adt7411_driver = {
 
 module_i2c_driver(adt7411_driver);
 
-MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de> and "
-	"Wolfram Sang <w.sang@pengutronix.de>");
+MODULE_AUTHOR("Sascha Hauer, Wolfram Sang <kernel@pengutronix.de>");
 MODULE_DESCRIPTION("ADT7411 driver");
 MODULE_LICENSE("GPL v2");
diff --git a/drivers/hwmon/amd_energy.c b/drivers/hwmon/amd_energy.c
new file mode 100644
index 000000000000..e95b7426106e
--- /dev/null
+++ b/drivers/hwmon/amd_energy.c
@@ -0,0 +1,408 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+/*
+ * Copyright (C) 2020 Advanced Micro Devices, Inc.
+ */
+#include <asm/cpu_device_id.h>
+
+#include <linux/bits.h>
+#include <linux/cpu.h>
+#include <linux/cpumask.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/hwmon.h>
+#include <linux/kernel.h>
+#include <linux/kthread.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/processor.h>
+#include <linux/platform_device.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/topology.h>
+#include <linux/types.h>
+
+#define DRVNAME			"amd_energy"
+
+#define ENERGY_PWR_UNIT_MSR	0xC0010299
+#define ENERGY_CORE_MSR		0xC001029A
+#define ENERGY_PKG_MSR		0xC001029B
+
+#define AMD_ENERGY_UNIT_MASK	0x01F00
+#define AMD_ENERGY_MASK		0xFFFFFFFF
+
+struct sensor_accumulator {
+	u64 energy_ctr;
+	u64 prev_value;
+	char label[10];
+};
+
+struct amd_energy_data {
+	struct hwmon_channel_info energy_info;
+	const struct hwmon_channel_info *info[2];
+	struct hwmon_chip_info chip;
+	struct task_struct *wrap_accumulate;
+	/* Lock around the accumulator */
+	struct mutex lock;
+	/* An accumulator for each core and socket */
+	struct sensor_accumulator *accums;
+	/* Energy Status Units */
+	u64 energy_units;
+	int nr_cpus;
+	int nr_socks;
+	int core_id;
+};
+
+static int amd_energy_read_labels(struct device *dev,
+				  enum hwmon_sensor_types type,
+				  u32 attr, int channel,
+				  const char **str)
+{
+	struct amd_energy_data *data = dev_get_drvdata(dev);
+
+	*str = data->accums[channel].label;
+	return 0;
+}
+
+static void get_energy_units(struct amd_energy_data *data)
+{
+	u64 rapl_units;
+
+	rdmsrl_safe(ENERGY_PWR_UNIT_MSR, &rapl_units);
+	data->energy_units = (rapl_units & AMD_ENERGY_UNIT_MASK) >> 8;
+}
+
+static void accumulate_socket_delta(struct amd_energy_data *data,
+				    int sock, int cpu)
+{
+	struct sensor_accumulator *s_accum;
+	u64 input;
+
+	mutex_lock(&data->lock);
+	rdmsrl_safe_on_cpu(cpu, ENERGY_PKG_MSR, &input);
+	input &= AMD_ENERGY_MASK;
+
+	s_accum = &data->accums[data->nr_cpus + sock];
+	if (input >= s_accum->prev_value)
+		s_accum->energy_ctr +=
+			input - s_accum->prev_value;
+	else
+		s_accum->energy_ctr += UINT_MAX -
+			s_accum->prev_value + input;
+
+	s_accum->prev_value = input;
+	mutex_unlock(&data->lock);
+}
+
+static void accumulate_core_delta(struct amd_energy_data *data)
+{
+	struct sensor_accumulator *c_accum;
+	u64 input;
+	int cpu;
+
+	mutex_lock(&data->lock);
+	if (data->core_id >= data->nr_cpus)
+		data->core_id = 0;
+
+	cpu = data->core_id;
+
+	if (!cpu_online(cpu))
+		goto out;
+
+	rdmsrl_safe_on_cpu(cpu, ENERGY_CORE_MSR, &input);
+	input &= AMD_ENERGY_MASK;
+
+	c_accum = &data->accums[cpu];
+
+	if (input >= c_accum->prev_value)
+		c_accum->energy_ctr +=
+			input - c_accum->prev_value;
+	else
+		c_accum->energy_ctr += UINT_MAX -
+			c_accum->prev_value + input;
+
+	c_accum->prev_value = input;
+
+out:
+	data->core_id++;
+	mutex_unlock(&data->lock);
+}
+
+static void read_accumulate(struct amd_energy_data *data)
+{
+	int sock;
+
+	for (sock = 0; sock < data->nr_socks; sock++) {
+		int cpu;
+
+		cpu = cpumask_first_and(cpu_online_mask,
+					cpumask_of_node(sock));
+
+		accumulate_socket_delta(data, sock, cpu);
+	}
+
+	accumulate_core_delta(data);
+}
+
+static void amd_add_delta(struct amd_energy_data *data, int ch,
+			  int cpu, long *val, bool is_core)
+{
+	struct sensor_accumulator *s_accum, *c_accum;
+	u64 input;
+
+	mutex_lock(&data->lock);
+	if (!is_core) {
+		rdmsrl_safe_on_cpu(cpu, ENERGY_PKG_MSR, &input);
+		input &= AMD_ENERGY_MASK;
+
+		s_accum = &data->accums[ch];
+		if (input >= s_accum->prev_value)
+			input += s_accum->energy_ctr -
+				  s_accum->prev_value;
+		else
+			input += UINT_MAX - s_accum->prev_value +
+				  s_accum->energy_ctr;
+	} else {
+		rdmsrl_safe_on_cpu(cpu, ENERGY_CORE_MSR, &input);
+		input &= AMD_ENERGY_MASK;
+
+		c_accum = &data->accums[ch];
+		if (input >= c_accum->prev_value)
+			input += c_accum->energy_ctr -
+				 c_accum->prev_value;
+		else
+			input += UINT_MAX - c_accum->prev_value +
+				 c_accum->energy_ctr;
+	}
+
+	/* Energy consumed = (1/(2^ESU) * RAW * 1000000UL) μJoules */
+	*val = div64_ul(input * 1000000UL, BIT(data->energy_units));
+
+	mutex_unlock(&data->lock);
+}
+
+static int amd_energy_read(struct device *dev,
+			   enum hwmon_sensor_types type,
+			   u32 attr, int channel, long *val)
+{
+	struct amd_energy_data *data = dev_get_drvdata(dev);
+	int cpu;
+
+	if (channel >= data->nr_cpus) {
+		cpu = cpumask_first_and(cpu_online_mask,
+					cpumask_of_node
+					(channel - data->nr_cpus));
+		amd_add_delta(data, channel, cpu, val, false);
+	} else {
+		cpu = channel;
+		if (!cpu_online(cpu))
+			return -ENODEV;
+
+		amd_add_delta(data, channel, cpu, val, true);
+	}
+
+	return 0;
+}
+
+static umode_t amd_energy_is_visible(const void *_data,
+				     enum hwmon_sensor_types type,
+				     u32 attr, int channel)
+{
+	return 0444;
+}
+
+static int energy_accumulator(void *p)
+{
+	struct amd_energy_data *data = (struct amd_energy_data *)p;
+
+	while (!kthread_should_stop()) {
+		/*
+		 * Ignoring the conditions such as
+		 * cpu being offline or rdmsr failure
+		 */
+		read_accumulate(data);
+
+		set_current_state(TASK_INTERRUPTIBLE);
+		if (kthread_should_stop())
+			break;
+
+		/*
+		 * On a 240W system, with default resolution the
+		 * Socket Energy status register may wrap around in
+		 * 2^32*15.3 e-6/240 = 273.8041 secs (~4.5 mins)
+		 *
+		 * let us accumulate for every 100secs
+		 */
+		schedule_timeout(msecs_to_jiffies(100000));
+	}
+	return 0;
+}
+
+static const struct hwmon_ops amd_energy_ops = {
+	.is_visible = amd_energy_is_visible,
+	.read = amd_energy_read,
+	.read_string = amd_energy_read_labels,
+};
+
+static int amd_create_sensor(struct device *dev,
+			     struct amd_energy_data *data,
+			     u8 type, u32 config)
+{
+	struct hwmon_channel_info *info = &data->energy_info;
+	struct sensor_accumulator *accums;
+	int i, num_siblings, cpus, sockets;
+	u32 *s_config;
+
+	/* Identify the number of siblings per core */
+	num_siblings = ((cpuid_ebx(0x8000001e) >> 8) & 0xff) + 1;
+
+	sockets = num_possible_nodes();
+
+	/*
+	 * Energy counter register is accessed at core level.
+	 * Hence, filterout the siblings.
+	 */
+	cpus = num_present_cpus() / num_siblings;
+
+	s_config = devm_kcalloc(dev, cpus + sockets,
+				sizeof(u32), GFP_KERNEL);
+	if (!s_config)
+		return -ENOMEM;
+
+	accums = devm_kcalloc(dev, cpus + sockets,
+			      sizeof(struct sensor_accumulator),
+			      GFP_KERNEL);
+	if (!accums)
+		return -ENOMEM;
+
+	info->type = type;
+	info->config = s_config;
+
+	data->nr_cpus = cpus;
+	data->nr_socks = sockets;
+	data->accums = accums;
+
+	for (i = 0; i < cpus + sockets; i++) {
+		s_config[i] = config;
+		if (i < cpus)
+			scnprintf(accums[i].label, 10,
+				  "Ecore%03u", i);
+		else
+			scnprintf(accums[i].label, 10,
+				  "Esocket%u", (i - cpus));
+	}
+
+	return 0;
+}
+
+static int amd_energy_probe(struct platform_device *pdev)
+{
+	struct device *hwmon_dev;
+	struct amd_energy_data *data;
+	struct device *dev = &pdev->dev;
+
+	data = devm_kzalloc(dev,
+			    sizeof(struct amd_energy_data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->chip.ops = &amd_energy_ops;
+	data->chip.info = data->info;
+
+	dev_set_drvdata(dev, data);
+	/* Populate per-core energy reporting */
+	data->info[0] = &data->energy_info;
+	amd_create_sensor(dev, data, hwmon_energy,
+			  HWMON_E_INPUT | HWMON_E_LABEL);
+
+	mutex_init(&data->lock);
+	get_energy_units(data);
+
+	hwmon_dev = devm_hwmon_device_register_with_info(dev, DRVNAME,
+							 data,
+							 &data->chip,
+							 NULL);
+	if (IS_ERR(hwmon_dev))
+		return PTR_ERR(hwmon_dev);
+
+	data->wrap_accumulate = kthread_run(energy_accumulator, data,
+					    "%s", dev_name(hwmon_dev));
+	if (IS_ERR(data->wrap_accumulate))
+		return PTR_ERR(data->wrap_accumulate);
+
+	return PTR_ERR_OR_ZERO(data->wrap_accumulate);
+}
+
+static int amd_energy_remove(struct platform_device *pdev)
+{
+	struct amd_energy_data *data = dev_get_drvdata(&pdev->dev);
+
+	if (data && data->wrap_accumulate)
+		kthread_stop(data->wrap_accumulate);
+
+	return 0;
+}
+
+static const struct platform_device_id amd_energy_ids[] = {
+	{ .name = DRVNAME, },
+	{}
+};
+MODULE_DEVICE_TABLE(platform, amd_energy_ids);
+
+static struct platform_driver amd_energy_driver = {
+	.probe = amd_energy_probe,
+	.remove	= amd_energy_remove,
+	.id_table = amd_energy_ids,
+	.driver = {
+		.name = DRVNAME,
+	},
+};
+
+static struct platform_device *amd_energy_platdev;
+
+static const struct x86_cpu_id cpu_ids[] __initconst = {
+	X86_MATCH_VENDOR_FAM(AMD, 0x17, NULL),
+	{}
+};
+MODULE_DEVICE_TABLE(x86cpu, cpu_ids);
+
+static int __init amd_energy_init(void)
+{
+	int ret;
+
+	if (!x86_match_cpu(cpu_ids))
+		return -ENODEV;
+
+	ret = platform_driver_register(&amd_energy_driver);
+	if (ret)
+		return ret;
+
+	amd_energy_platdev = platform_device_alloc(DRVNAME, 0);
+	if (!amd_energy_platdev) {
+		platform_driver_unregister(&amd_energy_driver);
+		return -ENOMEM;
+	}
+
+	ret = platform_device_add(amd_energy_platdev);
+	if (ret) {
+		platform_device_put(amd_energy_platdev);
+		platform_driver_unregister(&amd_energy_driver);
+		return ret;
+	}
+
+	return ret;
+}
+
+static void __exit amd_energy_exit(void)
+{
+	platform_device_unregister(amd_energy_platdev);
+	platform_driver_unregister(&amd_energy_driver);
+}
+
+module_init(amd_energy_init);
+module_exit(amd_energy_exit);
+
+MODULE_DESCRIPTION("Driver for AMD Energy reporting from RAPL MSR via HWMON interface");
+MODULE_AUTHOR("Naveen Krishna Chatradhi <nchatrad@amd.com>");
+MODULE_LICENSE("GPL");
diff --git a/drivers/hwmon/applesmc.c b/drivers/hwmon/applesmc.c
index ec93b8d673f5..316618409315 100644
--- a/drivers/hwmon/applesmc.c
+++ b/drivers/hwmon/applesmc.c
@@ -156,14 +156,19 @@ static struct workqueue_struct *applesmc_led_wq;
  */
 static int wait_read(void)
 {
+	unsigned long end = jiffies + (APPLESMC_MAX_WAIT * HZ) / USEC_PER_SEC;
 	u8 status;
 	int us;
+
 	for (us = APPLESMC_MIN_WAIT; us < APPLESMC_MAX_WAIT; us <<= 1) {
-		udelay(us);
+		usleep_range(us, us * 16);
 		status = inb(APPLESMC_CMD_PORT);
 		/* read: wait for smc to settle */
 		if (status & 0x01)
 			return 0;
+		/* timeout: give up */
+		if (time_after(jiffies, end))
+			break;
 	}
 
 	pr_warn("wait_read() fail: 0x%02x\n", status);
@@ -178,10 +183,11 @@ static int send_byte(u8 cmd, u16 port)
 {
 	u8 status;
 	int us;
+	unsigned long end = jiffies + (APPLESMC_MAX_WAIT * HZ) / USEC_PER_SEC;
 
 	outb(cmd, port);
 	for (us = APPLESMC_MIN_WAIT; us < APPLESMC_MAX_WAIT; us <<= 1) {
-		udelay(us);
+		usleep_range(us, us * 16);
 		status = inb(APPLESMC_CMD_PORT);
 		/* write: wait for smc to settle */
 		if (status & 0x02)
@@ -190,7 +196,7 @@ static int send_byte(u8 cmd, u16 port)
 		if (status & 0x04)
 			return 0;
 		/* timeout: give up */
-		if (us << 1 == APPLESMC_MAX_WAIT)
+		if (time_after(jiffies, end))
 			break;
 		/* busy: long wait and resend */
 		udelay(APPLESMC_RETRY_WAIT);
diff --git a/drivers/hwmon/bt1-pvt.c b/drivers/hwmon/bt1-pvt.c
new file mode 100644
index 000000000000..1a9772fb1f73
--- /dev/null
+++ b/drivers/hwmon/bt1-pvt.c
@@ -0,0 +1,1146 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2020 BAIKAL ELECTRONICS, JSC
+ *
+ * Authors:
+ *   Maxim Kaurkin <maxim.kaurkin@baikalelectronics.ru>
+ *   Serge Semin <Sergey.Semin@baikalelectronics.ru>
+ *
+ * Baikal-T1 Process, Voltage, Temperature sensor driver
+ */
+
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/completion.h>
+#include <linux/device.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/hwmon.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/ktime.h>
+#include <linux/limits.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/seqlock.h>
+#include <linux/sysfs.h>
+#include <linux/types.h>
+
+#include "bt1-pvt.h"
+
+/*
+ * For the sake of the code simplification we created the sensors info table
+ * with the sensor names, activation modes, threshold registers base address
+ * and the thresholds bit fields.
+ */
+static const struct pvt_sensor_info pvt_info[] = {
+	PVT_SENSOR_INFO(0, "CPU Core Temperature", hwmon_temp, TEMP, TTHRES),
+	PVT_SENSOR_INFO(0, "CPU Core Voltage", hwmon_in, VOLT, VTHRES),
+	PVT_SENSOR_INFO(1, "CPU Core Low-Vt", hwmon_in, LVT, LTHRES),
+	PVT_SENSOR_INFO(2, "CPU Core High-Vt", hwmon_in, HVT, HTHRES),
+	PVT_SENSOR_INFO(3, "CPU Core Standard-Vt", hwmon_in, SVT, STHRES),
+};
+
+/*
+ * The original translation formulae of the temperature (in degrees of Celsius)
+ * to PVT data and vice-versa are following:
+ * N = 1.8322e-8*(T^4) + 2.343e-5*(T^3) + 8.7018e-3*(T^2) + 3.9269*(T^1) +
+ *     1.7204e2,
+ * T = -1.6743e-11*(N^4) + 8.1542e-8*(N^3) + -1.8201e-4*(N^2) +
+ *     3.1020e-1*(N^1) - 4.838e1,
+ * where T = [-48.380, 147.438]C and N = [0, 1023].
+ * They must be accordingly altered to be suitable for the integer arithmetics.
+ * The technique is called 'factor redistribution', which just makes sure the
+ * multiplications and divisions are made so to have a result of the operations
+ * within the integer numbers limit. In addition we need to translate the
+ * formulae to accept millidegrees of Celsius. Here what they look like after
+ * the alterations:
+ * N = (18322e-20*(T^4) + 2343e-13*(T^3) + 87018e-9*(T^2) + 39269e-3*T +
+ *     17204e2) / 1e4,
+ * T = -16743e-12*(D^4) + 81542e-9*(D^3) - 182010e-6*(D^2) + 310200e-3*D -
+ *     48380,
+ * where T = [-48380, 147438] mC and N = [0, 1023].
+ */
+static const struct pvt_poly poly_temp_to_N = {
+	.total_divider = 10000,
+	.terms = {
+		{4, 18322, 10000, 10000},
+		{3, 2343, 10000, 10},
+		{2, 87018, 10000, 10},
+		{1, 39269, 1000, 1},
+		{0, 1720400, 1, 1}
+	}
+};
+
+static const struct pvt_poly poly_N_to_temp = {
+	.total_divider = 1,
+	.terms = {
+		{4, -16743, 1000, 1},
+		{3, 81542, 1000, 1},
+		{2, -182010, 1000, 1},
+		{1, 310200, 1000, 1},
+		{0, -48380, 1, 1}
+	}
+};
+
+/*
+ * Similar alterations are performed for the voltage conversion equations.
+ * The original formulae are:
+ * N = 1.8658e3*V - 1.1572e3,
+ * V = (N + 1.1572e3) / 1.8658e3,
+ * where V = [0.620, 1.168] V and N = [0, 1023].
+ * After the optimization they looks as follows:
+ * N = (18658e-3*V - 11572) / 10,
+ * V = N * 10^5 / 18658 + 11572 * 10^4 / 18658.
+ */
+static const struct pvt_poly poly_volt_to_N = {
+	.total_divider = 10,
+	.terms = {
+		{1, 18658, 1000, 1},
+		{0, -11572, 1, 1}
+	}
+};
+
+static const struct pvt_poly poly_N_to_volt = {
+	.total_divider = 10,
+	.terms = {
+		{1, 100000, 18658, 1},
+		{0, 115720000, 1, 18658}
+	}
+};
+
+/*
+ * Here is the polynomial calculation function, which performs the
+ * redistributed terms calculations. It's pretty straightforward. We walk
+ * over each degree term up to the free one, and perform the redistributed
+ * multiplication of the term coefficient, its divider (as for the rationale
+ * fraction representation), data power and the rational fraction divider
+ * leftover. Then all of this is collected in a total sum variable, which
+ * value is normalized by the total divider before being returned.
+ */
+static long pvt_calc_poly(const struct pvt_poly *poly, long data)
+{
+	const struct pvt_poly_term *term = poly->terms;
+	long tmp, ret = 0;
+	int deg;
+
+	do {
+		tmp = term->coef;
+		for (deg = 0; deg < term->deg; ++deg)
+			tmp = mult_frac(tmp, data, term->divider);
+		ret += tmp / term->divider_leftover;
+	} while ((term++)->deg);
+
+	return ret / poly->total_divider;
+}
+
+static inline u32 pvt_update(void __iomem *reg, u32 mask, u32 data)
+{
+	u32 old;
+
+	old = readl_relaxed(reg);
+	writel((old & ~mask) | (data & mask), reg);
+
+	return old & mask;
+}
+
+/*
+ * Baikal-T1 PVT mode can be updated only when the controller is disabled.
+ * So first we disable it, then set the new mode together with the controller
+ * getting back enabled. The same concerns the temperature trim and
+ * measurements timeout. If it is necessary the interface mutex is supposed
+ * to be locked at the time the operations are performed.
+ */
+static inline void pvt_set_mode(struct pvt_hwmon *pvt, u32 mode)
+{
+	u32 old;
+
+	mode = FIELD_PREP(PVT_CTRL_MODE_MASK, mode);
+
+	old = pvt_update(pvt->regs + PVT_CTRL, PVT_CTRL_EN, 0);
+	pvt_update(pvt->regs + PVT_CTRL, PVT_CTRL_MODE_MASK | PVT_CTRL_EN,
+		   mode | old);
+}
+
+static inline u32 pvt_calc_trim(long temp)
+{
+	temp = clamp_val(temp, 0, PVT_TRIM_TEMP);
+
+	return DIV_ROUND_UP(temp, PVT_TRIM_STEP);
+}
+
+static inline void pvt_set_trim(struct pvt_hwmon *pvt, u32 trim)
+{
+	u32 old;
+
+	trim = FIELD_PREP(PVT_CTRL_TRIM_MASK, trim);
+
+	old = pvt_update(pvt->regs + PVT_CTRL, PVT_CTRL_EN, 0);
+	pvt_update(pvt->regs + PVT_CTRL, PVT_CTRL_TRIM_MASK | PVT_CTRL_EN,
+		   trim | old);
+}
+
+static inline void pvt_set_tout(struct pvt_hwmon *pvt, u32 tout)
+{
+	u32 old;
+
+	old = pvt_update(pvt->regs + PVT_CTRL, PVT_CTRL_EN, 0);
+	writel(tout, pvt->regs + PVT_TTIMEOUT);
+	pvt_update(pvt->regs + PVT_CTRL, PVT_CTRL_EN, old);
+}
+
+/*
+ * This driver can optionally provide the hwmon alarms for each sensor the PVT
+ * controller supports. The alarms functionality is made compile-time
+ * configurable due to the hardware interface implementation peculiarity
+ * described further in this comment. So in case if alarms are unnecessary in
+ * your system design it's recommended to have them disabled to prevent the PVT
+ * IRQs being periodically raised to get the data cache/alarms status up to
+ * date.
+ *
+ * Baikal-T1 PVT embedded controller is based on the Analog Bits PVT sensor,
+ * but is equipped with a dedicated control wrapper. It exposes the PVT
+ * sub-block registers space via the APB3 bus. In addition the wrapper provides
+ * a common interrupt vector of the sensors conversion completion events and
+ * threshold value alarms. Alas the wrapper interface hasn't been fully thought
+ * through. There is only one sensor can be activated at a time, for which the
+ * thresholds comparator is enabled right after the data conversion is
+ * completed. Due to this if alarms need to be implemented for all available
+ * sensors we can't just set the thresholds and enable the interrupts. We need
+ * to enable the sensors one after another and let the controller to detect
+ * the alarms by itself at each conversion. This also makes pointless to handle
+ * the alarms interrupts, since in occasion they happen synchronously with
+ * data conversion completion. The best driver design would be to have the
+ * completion interrupts enabled only and keep the converted value in the
+ * driver data cache. This solution is implemented if hwmon alarms are enabled
+ * in this driver. In case if the alarms are disabled, the conversion is
+ * performed on demand at the time a sensors input file is read.
+ */
+
+#if defined(CONFIG_SENSORS_BT1_PVT_ALARMS)
+
+#define pvt_hard_isr NULL
+
+static irqreturn_t pvt_soft_isr(int irq, void *data)
+{
+	const struct pvt_sensor_info *info;
+	struct pvt_hwmon *pvt = data;
+	struct pvt_cache *cache;
+	u32 val, thres_sts, old;
+
+	/*
+	 * DVALID bit will be cleared by reading the data. We need to save the
+	 * status before the next conversion happens. Threshold events will be
+	 * handled a bit later.
+	 */
+	thres_sts = readl(pvt->regs + PVT_RAW_INTR_STAT);
+
+	/*
+	 * Then lets recharge the PVT interface with the next sampling mode.
+	 * Lock the interface mutex to serialize trim, timeouts and alarm
+	 * thresholds settings.
+	 */
+	cache = &pvt->cache[pvt->sensor];
+	info = &pvt_info[pvt->sensor];
+	pvt->sensor = (pvt->sensor == PVT_SENSOR_LAST) ?
+		      PVT_SENSOR_FIRST : (pvt->sensor + 1);
+
+	/*
+	 * For some reason we have to mask the interrupt before changing the
+	 * mode, otherwise sometim