Adding upstream version 6.1.76.upstream/6.1.76upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

7 files changed, 2151 insertions, 0 deletions

diff --git a/drivers/hwmon/occ/Kconfig b/drivers/hwmon/occ/Kconfig
new file mode 100644
index 000000000..35a7070db
--- /dev/null
+++ b/drivers/hwmon/occ/Kconfig
@@ -0,0 +1,37 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# On-Chip Controller configuration
+#
+
+config SENSORS_OCC_P8_I2C
+	tristate "POWER8 OCC through I2C"
+	depends on I2C
+	depends on ARM || ARM64 || COMPILE_TEST
+	select SENSORS_OCC
+	help
+	 This option enables support for monitoring sensors provided by the
+	 On-Chip Controller (OCC) on a POWER8 processor. However, this driver
+	 can only run on a baseboard management controller (BMC) connected to
+	 the P8, not the POWER processor itself. Communications with the OCC are
+	 established through I2C bus.
+
+	 This driver can also be built as a module. If so, the module will be
+	 called occ-p8-hwmon.
+
+config SENSORS_OCC_P9_SBE
+	tristate "POWER9 OCC through SBE"
+	depends on FSI_OCC
+	depends on ARM || ARM64 || COMPILE_TEST
+	select SENSORS_OCC
+	help
+	 This option enables support for monitoring sensors provided by the
+	 On-Chip Controller (OCC) on a POWER9 processor. However, this driver
+	 can only run on a baseboard management controller (BMC) connected to
+	 the P9, not the POWER processor itself. Communications with the OCC are
+	 established through SBE fifo on an FSI bus.
+
+	 This driver can also be built as a module. If so, the module will be
+	 called occ-p9-hwmon.
+
+config SENSORS_OCC
+	tristate
diff --git a/drivers/hwmon/occ/Makefile b/drivers/hwmon/occ/Makefile
new file mode 100644
index 000000000..810061765
--- /dev/null
+++ b/drivers/hwmon/occ/Makefile
@@ -0,0 +1,8 @@
+# SPDX-License-Identifier: GPL-2.0-only
+occ-hwmon-common-objs := common.o sysfs.o
+occ-p8-hwmon-objs := p8_i2c.o
+occ-p9-hwmon-objs := p9_sbe.o
+
+obj-$(CONFIG_SENSORS_OCC) += occ-hwmon-common.o
+obj-$(CONFIG_SENSORS_OCC_P8_I2C) += occ-p8-hwmon.o
+obj-$(CONFIG_SENSORS_OCC_P9_SBE) += occ-p9-hwmon.o
diff --git a/drivers/hwmon/occ/common.c b/drivers/hwmon/occ/common.c
new file mode 100644
index 000000000..dd690f700
--- /dev/null
+++ b/drivers/hwmon/occ/common.c
@@ -0,0 +1,1251 @@
+// SPDX-License-Identifier: GPL-2.0+
+// Copyright IBM Corp 2019
+
+#include <linux/device.h>
+#include <linux/export.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/jiffies.h>
+#include <linux/kernel.h>
+#include <linux/math64.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/property.h>
+#include <linux/sysfs.h>
+#include <asm/unaligned.h>
+
+#include "common.h"
+
+#define EXTN_FLAG_SENSOR_ID		BIT(7)
+
+#define OCC_ERROR_COUNT_THRESHOLD	2	/* required by OCC spec */
+
+#define OCC_STATE_SAFE			4
+#define OCC_SAFE_TIMEOUT		msecs_to_jiffies(60000) /* 1 min */
+
+#define OCC_UPDATE_FREQUENCY		msecs_to_jiffies(1000)
+
+#define OCC_TEMP_SENSOR_FAULT		0xFF
+
+#define OCC_FRU_TYPE_VRM		3
+
+/* OCC sensor type and version definitions */
+
+struct temp_sensor_1 {
+	u16 sensor_id;
+	u16 value;
+} __packed;
+
+struct temp_sensor_2 {
+	u32 sensor_id;
+	u8 fru_type;
+	u8 value;
+} __packed;
+
+struct temp_sensor_10 {
+	u32 sensor_id;
+	u8 fru_type;
+	u8 value;
+	u8 throttle;
+	u8 reserved;
+} __packed;
+
+struct freq_sensor_1 {
+	u16 sensor_id;
+	u16 value;
+} __packed;
+
+struct freq_sensor_2 {
+	u32 sensor_id;
+	u16 value;
+} __packed;
+
+struct power_sensor_1 {
+	u16 sensor_id;
+	u32 update_tag;
+	u32 accumulator;
+	u16 value;
+} __packed;
+
+struct power_sensor_2 {
+	u32 sensor_id;
+	u8 function_id;
+	u8 apss_channel;
+	u16 reserved;
+	u32 update_tag;
+	u64 accumulator;
+	u16 value;
+} __packed;
+
+struct power_sensor_data {
+	u16 value;
+	u32 update_tag;
+	u64 accumulator;
+} __packed;
+
+struct power_sensor_data_and_time {
+	u16 update_time;
+	u16 value;
+	u32 update_tag;
+	u64 accumulator;
+} __packed;
+
+struct power_sensor_a0 {
+	u32 sensor_id;
+	struct power_sensor_data_and_time system;
+	u32 reserved;
+	struct power_sensor_data_and_time proc;
+	struct power_sensor_data vdd;
+	struct power_sensor_data vdn;
+} __packed;
+
+struct caps_sensor_2 {
+	u16 cap;
+	u16 system_power;
+	u16 n_cap;
+	u16 max;
+	u16 min;
+	u16 user;
+	u8 user_source;
+} __packed;
+
+struct caps_sensor_3 {
+	u16 cap;
+	u16 system_power;
+	u16 n_cap;
+	u16 max;
+	u16 hard_min;
+	u16 soft_min;
+	u16 user;
+	u8 user_source;
+} __packed;
+
+struct extended_sensor {
+	union {
+		u8 name[4];
+		u32 sensor_id;
+	};
+	u8 flags;
+	u8 reserved;
+	u8 data[6];
+} __packed;
+
+static int occ_poll(struct occ *occ)
+{
+	int rc;
+	u8 cmd[7];
+	struct occ_poll_response_header *header;
+
+	/* big endian */
+	cmd[0] = 0;			/* sequence number */
+	cmd[1] = 0;			/* cmd type */
+	cmd[2] = 0;			/* data length msb */
+	cmd[3] = 1;			/* data length lsb */
+	cmd[4] = occ->poll_cmd_data;	/* data */
+	cmd[5] = 0;			/* checksum msb */
+	cmd[6] = 0;			/* checksum lsb */
+
+	/* mutex should already be locked if necessary */
+	rc = occ->send_cmd(occ, cmd, sizeof(cmd), &occ->resp, sizeof(occ->resp));
+	if (rc) {
+		occ->last_error = rc;
+		if (occ->error_count++ > OCC_ERROR_COUNT_THRESHOLD)
+			occ->error = rc;
+
+		goto done;
+	}
+
+	/* clear error since communication was successful */
+	occ->error_count = 0;
+	occ->last_error = 0;
+	occ->error = 0;
+
+	/* check for safe state */
+	header = (struct occ_poll_response_header *)occ->resp.data;
+	if (header->occ_state == OCC_STATE_SAFE) {
+		if (occ->last_safe) {
+			if (time_after(jiffies,
+				       occ->last_safe + OCC_SAFE_TIMEOUT))
+				occ->error = -EHOSTDOWN;
+		} else {
+			occ->last_safe = jiffies;
+		}
+	} else {
+		occ->last_safe = 0;
+	}
+
+done:
+	occ_sysfs_poll_done(occ);
+	return rc;
+}
+
+static int occ_set_user_power_cap(struct occ *occ, u16 user_power_cap)
+{
+	int rc;
+	u8 cmd[8];
+	u8 resp[8];
+	__be16 user_power_cap_be = cpu_to_be16(user_power_cap);
+
+	cmd[0] = 0;	/* sequence number */
+	cmd[1] = 0x22;	/* cmd type */
+	cmd[2] = 0;	/* data length msb */
+	cmd[3] = 2;	/* data length lsb */
+
+	memcpy(&cmd[4], &user_power_cap_be, 2);
+
+	cmd[6] = 0;	/* checksum msb */
+	cmd[7] = 0;	/* checksum lsb */
+
+	rc = mutex_lock_interruptible(&occ->lock);
+	if (rc)
+		return rc;
+
+	rc = occ->send_cmd(occ, cmd, sizeof(cmd), resp, sizeof(resp));
+
+	mutex_unlock(&occ->lock);
+
+	return rc;
+}
+
+int occ_update_response(struct occ *occ)
+{
+	int rc = mutex_lock_interruptible(&occ->lock);
+
+	if (rc)
+		return rc;
+
+	/* limit the maximum rate of polling the OCC */
+	if (time_after(jiffies, occ->next_update)) {
+		rc = occ_poll(occ);
+		occ->next_update = jiffies + OCC_UPDATE_FREQUENCY;
+	} else {
+		rc = occ->last_error;
+	}
+
+	mutex_unlock(&occ->lock);
+	return rc;
+}
+
+static ssize_t occ_show_temp_1(struct device *dev,
+			       struct device_attribute *attr, char *buf)
+{
+	int rc;
+	u32 val = 0;
+	struct temp_sensor_1 *temp;
+	struct occ *occ = dev_get_drvdata(dev);
+	struct occ_sensors *sensors = &occ->sensors;
+	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
+
+	rc = occ_update_response(occ);
+	if (rc)
+		return rc;
+
+	temp = ((struct temp_sensor_1 *)sensors->temp.data) + sattr->index;
+
+	switch (sattr->nr) {
+	case 0:
+		val = get_unaligned_be16(&temp->sensor_id);
+		break;
+	case 1:
+		/*
+		 * If a sensor reading has expired and couldn't be refreshed,
+		 * OCC returns 0xFFFF for that sensor.
+		 */
+		if (temp->value == 0xFFFF)
+			return -EREMOTEIO;
+		val = get_unaligned_be16(&temp->value) * 1000;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return sysfs_emit(buf, "%u\n", val);
+}
+
+static ssize_t occ_show_temp_2(struct device *dev,
+			       struct device_attribute *attr, char *buf)
+{
+	int rc;
+	u32 val = 0;
+	struct temp_sensor_2 *temp;
+	struct occ *occ = dev_get_drvdata(dev);
+	struct occ_sensors *sensors = &occ->sensors;
+	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
+
+	rc = occ_update_response(occ);
+	if (rc)
+		return rc;
+
+	temp = ((struct temp_sensor_2 *)sensors->temp.data) + sattr->index;
+
+	switch (sattr->nr) {
+	case 0:
+		val = get_unaligned_be32(&temp->sensor_id);
+		break;
+	case 1:
+		val = temp->value;
+		if (val == OCC_TEMP_SENSOR_FAULT)
+			return -EREMOTEIO;
+
+		/*
+		 * VRM doesn't return temperature, only alarm bit. This
+		 * attribute maps to tempX_alarm instead of tempX_input for
+		 * VRM
+		 */
+		if (temp->fru_type != OCC_FRU_TYPE_VRM) {
+			/* sensor not ready */
+			if (val == 0)
+				return -EAGAIN;
+
+			val *= 1000;
+		}
+		break;
+	case 2:
+		val = temp->fru_type;
+		break;
+	case 3:
+		val = temp->value == OCC_TEMP_SENSOR_FAULT;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return sysfs_emit(buf, "%u\n", val);
+}
+
+static ssize_t occ_show_temp_10(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	int rc;
+	u32 val = 0;
+	struct temp_sensor_10 *temp;
+	struct occ *occ = dev_get_drvdata(dev);
+	struct occ_sensors *sensors = &occ->sensors;
+	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
+
+	rc = occ_update_response(occ);
+	if (rc)
+		return rc;
+
+	temp = ((struct temp_sensor_10 *)sensors->temp.data) + sattr->index;
+
+	switch (sattr->nr) {
+	case 0:
+		val = get_unaligned_be32(&temp->sensor_id);
+		break;
+	case 1:
+		val = temp->value;
+		if (val == OCC_TEMP_SENSOR_FAULT)
+			return -EREMOTEIO;
+
+		/* sensor not ready */
+		if (val == 0)
+			return -EAGAIN;
+
+		val *= 1000;
+		break;
+	case 2:
+		val = temp->fru_type;
+		break;
+	case 3:
+		val = temp->value == OCC_TEMP_SENSOR_FAULT;
+		break;
+	case 4:
+		val = temp->throttle * 1000;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return sysfs_emit(buf, "%u\n", val);
+}
+
+static ssize_t occ_show_freq_1(struct device *dev,
+			       struct device_attribute *attr, char *buf)
+{
+	int rc;
+	u16 val = 0;
+	struct freq_sensor_1 *freq;
+	struct occ *occ = dev_get_drvdata(dev);
+	struct occ_sensors *sensors = &occ->sensors;
+	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
+
+	rc = occ_update_response(occ);
+	if (rc)
+		return rc;
+
+	freq = ((struct freq_sensor_1 *)sensors->freq.data) + sattr->index;
+
+	switch (sattr->nr) {
+	case 0:
+		val = get_unaligned_be16(&freq->sensor_id);
+		break;
+	case 1:
+		val = get_unaligned_be16(&freq->value);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return sysfs_emit(buf, "%u\n", val);
+}
+
+static ssize_t occ_show_freq_2(struct device *dev,
+			       struct device_attribute *attr, char *buf)
+{
+	int rc;
+	u32 val = 0;
+	struct freq_sensor_2 *freq;
+	struct occ *occ = dev_get_drvdata(dev);
+	struct occ_sensors *sensors = &occ->sensors;
+	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
+
+	rc = occ_update_response(occ);
+	if (rc)
+		return rc;
+
+	freq = ((struct freq_sensor_2 *)sensors->freq.data) + sattr->index;
+
+	switch (sattr->nr) {
+	case 0:
+		val = get_unaligned_be32(&freq->sensor_id);
+		break;
+	case 1:
+		val = get_unaligned_be16(&freq->value);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return sysfs_emit(buf, "%u\n", val);
+}
+
+static ssize_t occ_show_power_1(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	int rc;
+	u64 val = 0;
+	struct power_sensor_1 *power;
+	struct occ *occ = dev_get_drvdata(dev);
+	struct occ_sensors *sensors = &occ->sensors;
+	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
+
+	rc = occ_update_response(occ);
+	if (rc)
+		return rc;
+
+	power = ((struct power_sensor_1 *)sensors->power.data) + sattr->index;
+
+	switch (sattr->nr) {
+	case 0:
+		val = get_unaligned_be16(&power->sensor_id);
+		break;
+	case 1:
+		val = get_unaligned_be32(&power->accumulator) /
+			get_unaligned_be32(&power->update_tag);
+		val *= 1000000ULL;
+		break;
+	case 2:
+		val = (u64)get_unaligned_be32(&power->update_tag) *
+			   occ->powr_sample_time_us;
+		break;
+	case 3:
+		val = get_unaligned_be16(&power->value) * 1000000ULL;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return sysfs_emit(buf, "%llu\n", val);
+}
+
+static u64 occ_get_powr_avg(u64 *accum, u32 *samples)
+{
+	u64 divisor = get_unaligned_be32(samples);
+
+	return (divisor == 0) ? 0 :
+		div64_u64(get_unaligned_be64(accum) * 1000000ULL, divisor);
+}
+
+static ssize_t occ_show_power_2(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	int rc;
+	u64 val = 0;
+	struct power_sensor_2 *power;
+	struct occ *occ = dev_get_drvdata(dev);
+	struct occ_sensors *sensors = &occ->sensors;
+	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
+
+	rc = occ_update_response(occ);
+	if (rc)
+		return rc;
+
+	power = ((struct power_sensor_2 *)sensors->power.data) + sattr->index;
+
+	switch (sattr->nr) {
+	case 0:
+		return sysfs_emit(buf, "%u_%u_%u\n",
+				  get_unaligned_be32(&power->sensor_id),
+				  power->function_id, power->apss_channel);
+	case 1:
+		val = occ_get_powr_avg(&power->accumulator,
+				       &power->update_tag);
+		break;
+	case 2:
+		val = (u64)get_unaligned_be32(&power->update_tag) *
+			   occ->powr_sample_time_us;
+		break;
+	case 3:
+		val = get_unaligned_be16(&power->value) * 1000000ULL;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return sysfs_emit(buf, "%llu\n", val);
+}
+
+static ssize_t occ_show_power_a0(struct device *dev,
+				 struct device_attribute *attr, char *buf)
+{
+	int rc;
+	u64 val = 0;
+	struct power_sensor_a0 *power;
+	struct occ *occ = dev_get_drvdata(dev);
+	struct occ_sensors *sensors = &occ->sensors;
+	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
+
+	rc = occ_update_response(occ);
+	if (rc)
+		return rc;
+
+	power = ((struct power_sensor_a0 *)sensors->power.data) + sattr->index;
+
+	switch (sattr->nr) {
+	case 0:
+		return sysfs_emit(buf, "%u_system\n",
+				  get_unaligned_be32(&power->sensor_id));
+	case 1:
+		val = occ_get_powr_avg(&power->system.accumulator,
+				       &power->system.update_tag);
+		break;
+	case 2:
+		val = (u64)get_unaligned_be32(&power->system.update_tag) *
+			   occ->powr_sample_time_us;
+		break;
+	case 3:
+		val = get_unaligned_be16(&power->system.value) * 1000000ULL;
+		break;
+	case 4:
+		return sysfs_emit(buf, "%u_proc\n",
+				  get_unaligned_be32(&power->sensor_id));
+	case 5:
+		val = occ_get_powr_avg(&power->proc.accumulator,
+				       &power->proc.update_tag);
+		break;
+	case 6:
+		val = (u64)get_unaligned_be32(&power->proc.update_tag) *
+			   occ->powr_sample_time_us;
+		break;
+	case 7:
+		val = get_unaligned_be16(&power->proc.value) * 1000000ULL;
+		break;
+	case 8:
+		return sysfs_emit(buf, "%u_vdd\n",
+				  get_unaligned_be32(&power->sensor_id));
+	case 9:
+		val = occ_get_powr_avg(&power->vdd.accumulator,
+				       &power->vdd.update_tag);
+		break;
+	case 10:
+		val = (u64)get_unaligned_be32(&power->vdd.update_tag) *
+			   occ->powr_sample_time_us;
+		break;
+	case 11:
+		val = get_unaligned_be16(&power->vdd.value) * 1000000ULL;
+		break;
+	case 12:
+		return sysfs_emit(buf, "%u_vdn\n",
+				  get_unaligned_be32(&power->sensor_id));
+	case 13:
+		val = occ_get_powr_avg(&power->vdn.accumulator,
+				       &power->vdn.update_tag);
+		break;
+	case 14:
+		val = (u64)get_unaligned_be32(&power->vdn.update_tag) *
+			   occ->powr_sample_time_us;
+		break;
+	case 15:
+		val = get_unaligned_be16(&power->vdn.value) * 1000000ULL;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return sysfs_emit(buf, "%llu\n", val);
+}
+
+static ssize_t occ_show_caps_1_2(struct device *dev,
+				 struct device_attribute *attr, char *buf)
+{
+	int rc;
+	u64 val = 0;
+	struct caps_sensor_2 *caps;
+	struct occ *occ = dev_get_drvdata(dev);
+	struct occ_sensors *sensors = &occ->sensors;
+	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
+
+	rc = occ_update_response(occ);
+	if (rc)
+		return rc;
+
+	caps = ((struct caps_sensor_2 *)sensors->caps.data) + sattr->index;
+
+	switch (sattr->nr) {
+	case 0:
+		return sysfs_emit(buf, "system\n");
+	case 1:
+		val = get_unaligned_be16(&caps->cap) * 1000000ULL;
+		break;
+	case 2:
+		val = get_unaligned_be16(&caps->system_power) * 1000000ULL;
+		break;
+	case 3:
+		val = get_unaligned_be16(&caps->n_cap) * 1000000ULL;
+		break;
+	case 4:
+		val = get_unaligned_be16(&caps->max) * 1000000ULL;
+		break;
+	case 5:
+		val = get_unaligned_be16(&caps->min) * 1000000ULL;
+		break;
+	case 6:
+		val = get_unaligned_be16(&caps->user) * 1000000ULL;
+		break;
+	case 7:
+		if (occ->sensors.caps.version == 1)
+			return -EINVAL;
+
+		val = caps->user_source;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return sysfs_emit(buf, "%llu\n", val);
+}
+
+static ssize_t occ_show_caps_3(struct device *dev,
+			       struct device_attribute *attr, char *buf)
+{
+	int rc;
+	u64 val = 0;
+	struct caps_sensor_3 *caps;
+	struct occ *occ = dev_get_drvdata(dev);
+	struct occ_sensors *sensors = &occ->sensors;
+	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
+
+	rc = occ_update_response(occ);
+	if (rc)
+		return rc;
+
+	caps = ((struct caps_sensor_3 *)sensors->caps.data) + sattr->index;
+
+	switch (sattr->nr) {
+	case 0:
+		return sysfs_emit(buf, "system\n");
+	case 1:
+		val = get_unaligned_be16(&caps->cap) * 1000000ULL;
+		break;
+	case 2:
+		val = get_unaligned_be16(&caps->system_power) * 1000000ULL;
+		break;
+	case 3:
+		val = get_unaligned_be16(&caps->n_cap) * 1000000ULL;
+		break;
+	case 4:
+		val = get_unaligned_be16(&caps->max) * 1000000ULL;
+		break;
+	case 5:
+		val = get_unaligned_be16(&caps->hard_min) * 1000000ULL;
+		break;
+	case 6:
+		val = get_unaligned_be16(&caps->user) * 1000000ULL;
+		break;
+	case 7:
+		val = caps->user_source;
+		break;
+	case 8:
+		val = get_unaligned_be16(&caps->soft_min) * 1000000ULL;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return sysfs_emit(buf, "%llu\n", val);
+}
+
+static ssize_t occ_store_caps_user(struct device *dev,
+				   struct device_attribute *attr,
+				   const char *buf, size_t count)
+{
+	int rc;
+	u16 user_power_cap;
+	unsigned long long value;
+	struct occ *occ = dev_get_drvdata(dev);
+
+	rc = kstrtoull(buf, 0, &value);
+	if (rc)
+		return rc;
+
+	user_power_cap = div64_u64(value, 1000000ULL); /* microwatt to watt */
+
+	rc = occ_set_user_power_cap(occ, user_power_cap);
+	if (rc)
+		return rc;
+
+	return count;
+}
+
+static ssize_t occ_show_extended(struct device *dev,
+				 struct device_attribute *attr, char *buf)
+{
+	int rc;
+	struct extended_sensor *extn;
+	struct occ *occ = dev_get_drvdata(dev);
+	struct occ_sensors *sensors = &occ->sensors;
+	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
+
+	rc = occ_update_response(occ);
+	if (rc)
+		return rc;
+
+	extn = ((struct extended_sensor *)sensors->extended.data) +
+		sattr->index;
+
+	switch (sattr->nr) {
+	case 0:
+		if (extn->flags & EXTN_FLAG_SENSOR_ID) {
+			rc = sysfs_emit(buf, "%u",
+					get_unaligned_be32(&extn->sensor_id));
+		} else {
+			rc = sysfs_emit(buf, "%4phN\n", extn->name);
+		}
+		break;
+	case 1:
+		rc = sysfs_emit(buf, "%02x\n", extn->flags);
+		break;
+	case 2:
+		rc = sysfs_emit(buf, "%6phN\n", extn->data);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return rc;
+}
+
+/*
+ * Some helper macros to make it easier to define an occ_attribute. Since these
+ * are dynamically allocated, we shouldn't use the existing kernel macros which
+ * stringify the name argument.
+ */
+#define ATTR_OCC(_name, _mode, _show, _store) {				\
+	.attr	= {							\
+		.name = _name,						\
+		.mode = VERIFY_OCTAL_PERMISSIONS(_mode),		\
+	},								\
+	.show	= _show,						\
+	.store	= _store,						\
+}
+
+#define SENSOR_ATTR_OCC(_name, _mode, _show, _store, _nr, _index) {	\
+	.dev_attr	= ATTR_OCC(_name, _mode, _show, _store),	\
+	.index		= _index,					\
+	.nr		= _nr,						\
+}
+
+#define OCC_INIT_ATTR(_name, _mode, _show, _store, _nr, _index)		\
+	((struct sensor_device_attribute_2)				\
+		SENSOR_ATTR_OCC(_name, _mode, _show, _store, _nr, _index))
+
+/*
+ * Allocate and instatiate sensor_device_attribute_2s. It's most efficient to
+ * use our own instead of the built-in hwmon attribute types.
+ */
+static int occ_setup_sensor_attrs(struct occ *occ)
+{
+	unsigned int i, s, num_attrs = 0;
+	struct device *dev = occ->bus_dev;
+	struct occ_sensors *sensors = &occ->sensors;
+	struct occ_attribute *attr;
+	struct temp_sensor_2 *temp;
+	ssize_t (*show_temp)(struct device *, struct device_attribute *,
+			     char *) = occ_show_temp_1;
+	ssize_t (*show_freq)(struct device *, struct device_attribute *,
+			     char *) = occ_show_freq_1;
+	ssize_t (*show_power)(struct device *, struct device_attribute *,
+			      char *) = occ_show_power_1;
+	ssize_t (*show_caps)(struct device *, struct device_attribute *,
+			     char *) = occ_show_caps_1_2;
+
+	switch (sensors->temp.version) {
+	case 1:
+		num_attrs += (sensors->temp.num_sensors * 2);
+		break;
+	case 2:
+		num_attrs += (sensors->temp.num_sensors * 4);
+		show_temp = occ_show_temp_2;
+		break;
+	case 0x10:
+		num_attrs += (sensors->temp.num_sensors * 5);
+		show_temp = occ_show_temp_10;
+		break;
+	default:
+		sensors->temp.num_sensors = 0;
+	}
+
+	switch (sensors->freq.version) {
+	case 2:
+		show_freq = occ_show_freq_2;
+		fallthrough;
+	case 1:
+		num_attrs += (sensors->freq.num_sensors * 2);
+		break;
+	default:
+		sensors->freq.num_sensors = 0;
+	}
+
+	switch (sensors->power.version) {
+	case 2:
+		show_power = occ_show_power_2;
+		fallthrough;
+	case 1:
+		num_attrs += (sensors->power.num_sensors * 4);
+		break;
+	case 0xA0:
+		num_attrs += (sensors->power.num_sensors * 16);
+		show_power = occ_show_power_a0;
+		break;
+	default:
+		sensors->power.num_sensors = 0;
+	}
+
+	switch (sensors->caps.version) {
+	case 1:
+		num_attrs += (sensors->caps.num_sensors * 7);
+		break;
+	case 2:
+		num_attrs += (sensors->caps.num_sensors * 8);
+		break;
+	case 3:
+		show_caps = occ_show_caps_3;
+		num_attrs += (sensors->caps.num_sensors * 9);
+		break;
+	default:
+		sensors->caps.num_sensors = 0;
+	}
+
+	switch (sensors->extended.version) {
+	case 1:
+		num_attrs += (sensors->extended.num_sensors * 3);
+		break;
+	default:
+		sensors->extended.num_sensors = 0;
+	}
+
+	occ->attrs = devm_kzalloc(dev, sizeof(*occ->attrs) * num_attrs,
+				  GFP_KERNEL);
+	if (!occ->attrs)
+		return -ENOMEM;
+
+	/* null-terminated list */
+	occ->group.attrs = devm_kzalloc(dev, sizeof(*occ->group.attrs) *
+					num_attrs + 1, GFP_KERNEL);
+	if (!occ->group.attrs)
+		return -ENOMEM;
+
+	attr = occ->attrs;
+
+	for (i = 0; i < sensors->temp.num_sensors; ++i) {
+		s = i + 1;
+		temp = ((struct temp_sensor_2 *)sensors->temp.data) + i;
+
+		snprintf(attr->name, sizeof(attr->name), "temp%d_label", s);
+		attr->sensor = OCC_INIT_ATTR(attr->name, 0444, show_temp, NULL,
+					     0, i);
+		attr++;
+
+		if (sensors->temp.version == 2 &&
+		    temp->fru_type == OCC_FRU_TYPE_VRM) {
+			snprintf(attr->name, sizeof(attr->name),
+				 "temp%d_alarm", s);
+		} else {
+			snprintf(attr->name, sizeof(attr->name),
+				 "temp%d_input", s);
+		}
+
+		attr->sensor = OCC_INIT_ATTR(attr->name, 0444, show_temp, NULL,
+					     1, i);
+		attr++;
+
+		if (sensors->temp.version > 1) {
+			snprintf(attr->name, sizeof(attr->name),
+				 "temp%d_fru_type", s);
+			attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
+						     show_temp, NULL, 2, i);
+			attr++;
+
+			snprintf(attr->name, sizeof(attr->name),
+				 "temp%d_fault", s);
+			attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
+						     show_temp, NULL, 3, i);
+			attr++;
+
+			if (sensors->temp.version == 0x10) {
+				snprintf(attr->name, sizeof(attr->name),
+					 "temp%d_max", s);
+				attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
+							     show_temp, NULL,
+							     4, i);
+				attr++;
+			}
+		}
+	}
+
+	for (i = 0; i < sensors->freq.num_sensors; ++i) {
+		s = i + 1;
+
+		snprintf(attr->name, sizeof(attr->name), "freq%d_label", s);
+		attr->sensor = OCC_INIT_ATTR(attr->name, 0444, show_freq, NULL,
+					     0, i);
+		attr++;
+
+		snprintf(attr->name, sizeof(attr->name), "freq%d_input", s);
+		attr->sensor = OCC_INIT_ATTR(attr->name, 0444, show_freq, NULL,
+					     1, i);
+		attr++;
+	}
+
+	if (sensors->power.version == 0xA0) {
+		/*
+		 * Special case for many-attribute power sensor. Split it into
+		 * a sensor number per power type, emulating several sensors.
+		 */
+		for (i = 0; i < sensors->power.num_sensors; ++i) {
+			unsigned int j;
+			unsigned int nr = 0;
+
+			s = (i * 4) + 1;
+
+			for (j = 0; j < 4; ++j) {
+				snprintf(attr->name, sizeof(attr->name),
+					 "power%d_label", s);
+				attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
+							     show_power, NULL,
+							     nr++, i);
+				attr++;
+
+				snprintf(attr->name, sizeof(attr->name),
+					 "power%d_average", s);
+				attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
+							     show_power, NULL,
+							     nr++, i);
+				attr++;
+
+				snprintf(attr->name, sizeof(attr->name),
+					 "power%d_average_interval", s);
+				attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
+							     show_power, NULL,
+							     nr++, i);
+				attr++;
+
+				snprintf(attr->name, sizeof(attr->name),
+					 "power%d_input", s);
+				attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
+							     show_power, NULL,
+							     nr++, i);
+				attr++;
+
+				s++;
+			}
+		}
+
+		s = (sensors->power.num_sensors * 4) + 1;
+	} else {
+		for (i = 0; i < sensors->power.num_sensors; ++i) {
+			s = i + 1;
+
+			snprintf(attr->name, sizeof(attr->name),
+				 "power%d_label", s);
+			attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
+						     show_power, NULL, 0, i);
+			attr++;
+
+			snprintf(attr->name, sizeof(attr->name),
+				 "power%d_average", s);
+			attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
+						     show_power, NULL, 1, i);
+			attr++;
+
+			snprintf(attr->name, sizeof(attr->name),
+				 "power%d_average_interval", s);
+			attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
+						     show_power, NULL, 2, i);
+			attr++;
+
+			snprintf(attr->name, sizeof(attr->name),
+				 "power%d_input", s);
+			attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
+						     show_power, NULL, 3, i);
+			attr++;
+		}
+
+		s = sensors->power.num_sensors + 1;
+	}
+
+	if (sensors->caps.num_sensors >= 1) {
+		snprintf(attr->name, sizeof(attr->name), "power%d_label", s);
+		attr->sensor = OCC_INIT_ATTR(attr->name, 0444, show_caps, NULL,
+					     0, 0);
+		attr++;
+
+		snprintf(attr->name, sizeof(attr->name), "power%d_cap", s);
+		attr->sensor = OCC_INIT_ATTR(attr->name, 0444, show_caps, NULL,
+					     1, 0);
+		attr++;
+
+		snprintf(attr->name, sizeof(attr->name), "power%d_input", s);
+		attr->sensor = OCC_INIT_ATTR(attr->name, 0444, show_caps, NULL,
+					     2, 0);
+		attr++;
+
+		snprintf(attr->name, sizeof(attr->name),
+			 "power%d_cap_not_redundant", s);
+		attr->sensor = OCC_INIT_ATTR(attr->name, 0444, show_caps, NULL,
+					     3, 0);
+		attr++;
+
+		snprintf(attr->name, sizeof(attr->name), "power%d_cap_max", s);
+		attr->sensor = OCC_INIT_ATTR(attr->name, 0444, show_caps, NULL,
+					     4, 0);
+		attr++;
+
+		snprintf(attr->name, sizeof(attr->name), "power%d_cap_min", s);
+		attr->sensor = OCC_INIT_ATTR(attr->name, 0444, show_caps, NULL,
+					     5, 0);
+		attr++;
+
+		snprintf(attr->name, sizeof(attr->name), "power%d_cap_user",
+			 s);
+		attr->sensor = OCC_INIT_ATTR(attr->name, 0644, show_caps,
+					     occ_store_caps_user, 6, 0);
+		attr++;
+
+		if (sensors->caps.version > 1) {
+			snprintf(attr->name, sizeof(attr->name),
+				 "power%d_cap_user_source", s);
+			attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
+						     show_caps, NULL, 7, 0);
+			attr++;
+
+			if (sensors->caps.version > 2) {
+				snprintf(attr->name, sizeof(attr->name),
+					 "power%d_cap_min_soft", s);
+				attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
+							     show_caps, NULL,
+							     8, 0);
+				attr++;
+			}
+		}
+	}
+
+	for (i = 0; i < sensors->extended.num_sensors; ++i) {
+		s = i + 1;
+
+		snprintf(attr->name, sizeof(attr->name), "extn%d_label", s);
+		attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
+					     occ_show_extended, NULL, 0, i);
+		attr++;
+
+		snprintf(attr->name, sizeof(attr->name), "extn%d_flags", s);
+		attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
+					     occ_show_extended, NULL, 1, i);
+		attr++;
+
+		snprintf(attr->name, sizeof(attr->name), "extn%d_input", s);
+		attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
+					     occ_show_extended, NULL, 2, i);
+		attr++;
+	}
+
+	/* put the sensors in the group */
+	for (i = 0; i < num_attrs; ++i) {
+		sysfs_attr_init(&occ->attrs[i].sensor.dev_attr.attr);
+		occ->group.attrs[i] = &occ->attrs[i].sensor.dev_attr.attr;
+	}
+
+	return 0;
+}
+
+/* only need to do this once at startup, as OCC won't change sensors on us */
+static void occ_parse_poll_response(struct occ *occ)
+{
+	unsigned int i, old_offset, offset = 0, size = 0;
+	struct occ_sensor *sensor;
+	struct occ_sensors *sensors = &occ->sensors;
+	struct occ_response *resp = &occ->resp;
+	struct occ_poll_response *poll =
+		(struct occ_poll_response *)&resp->data[0];
+	struct occ_poll_response_header *header = &poll->header;
+	struct occ_sensor_data_block *block = &poll->block;
+
+	dev_info(occ->bus_dev, "OCC found, code level: %.16s\n",
+		 header->occ_code_level);
+
+	for (i = 0; i < header->num_sensor_data_blocks; ++i) {
+		block = (struct occ_sensor_data_block *)((u8 *)block + offset);
+		old_offset = offset;
+		offset = (block->header.num_sensors *
+			  block->header.sensor_length) + sizeof(block->header);
+		size += offset;
+
+		/* validate all the length/size fields */
+		if ((size + sizeof(*header)) >= OCC_RESP_DATA_BYTES) {
+			dev_warn(occ->bus_dev, "exceeded response buffer\n");
+			return;
+		}
+
+		dev_dbg(occ->bus_dev, " %04x..%04x: %.4s (%d sensors)\n",
+			old_offset, offset - 1, block->header.eye_catcher,
+			block->header.num_sensors);
+
+		/* match sensor block type */
+		if (strncmp(block->header.eye_catcher, "TEMP", 4) == 0)
+			sensor = &sensors->temp;
+		else if (strncmp(block->header.eye_catcher, "FREQ", 4) == 0)
+			sensor = &sensors->freq;
+		else if (strncmp(block->header.eye_catcher, "POWR", 4) == 0)
+			sensor = &sensors->power;
+		else if (strncmp(block->header.eye_catcher, "CAPS", 4) == 0)
+			sensor = &sensors->caps;
+		else if (strncmp(block->header.eye_catcher, "EXTN", 4) == 0)
+			sensor = &sensors->extended;
+		else {
+			dev_warn(occ->bus_dev, "sensor not supported %.4s\n",
+				 block->header.eye_catcher);
+			continue;
+		}
+
+		sensor->num_sensors = block->header.num_sensors;
+		sensor->version = block->header.sensor_format;
+		sensor->data = &block->data;
+	}
+
+	dev_dbg(occ->bus_dev, "Max resp size: %u+%zd=%zd\n", size,
+		sizeof(*header), size + sizeof(*header));
+}
+
+int occ_active(struct occ *occ, bool active)
+{
+	int rc = mutex_lock_interruptible(&occ->lock);
+
+	if (rc)
+		return rc;
+
+	if (active) {
+		if (occ->active) {
+			rc = -EALREADY;
+			goto unlock;
+		}
+
+		occ->error_count = 0;
+		occ->last_safe = 0;
+
+		rc = occ_poll(occ);
+		if (rc < 0) {
+			dev_err(occ->bus_dev,
+				"failed to get OCC poll response=%02x: %d\n",
+				occ->resp.return_status, rc);
+			goto unlock;
+		}
+
+		occ->active = true;
+		occ->next_update = jiffies + OCC_UPDATE_FREQUENCY;
+		occ_parse_poll_response(occ);
+
+		rc = occ_setup_sensor_attrs(occ);
+		if (rc) {
+			dev_err(occ->bus_dev,
+				"failed to setup sensor attrs: %d\n", rc);
+			goto unlock;
+		}
+
+		occ->hwmon = hwmon_device_register_with_groups(occ->bus_dev,
+							       "occ", occ,
+							       occ->groups);
+		if (IS_ERR(occ->hwmon)) {
+			rc = PTR_ERR(occ->hwmon);
+			occ->hwmon = NULL;
+			dev_err(occ->bus_dev,
+				"failed to register hwmon device: %d\n", rc);
+			goto unlock;
+		}
+	} else {
+		if (!occ->active) {
+			rc = -EALREADY;
+			goto unlock;
+		}
+
+		if (occ->hwmon)
+			hwmon_device_unregister(occ->hwmon);
+		occ->active = false;
+		occ->hwmon = NULL;
+	}
+
+unlock:
+	mutex_unlock(&occ->lock);
+	return rc;
+}
+
+int occ_setup(struct occ *occ)
+{
+	int rc;
+
+	mutex_init(&occ->lock);
+	occ->groups[0] = &occ->group;
+
+	rc = occ_setup_sysfs(occ);
+	if (rc) {
+		dev_err(occ->bus_dev, "failed to setup sysfs: %d\n", rc);
+		return rc;
+	}
+
+	if (!device_property_read_bool(occ->bus_dev, "ibm,no-poll-on-init")) {
+		rc = occ_active(occ, true);
+		if (rc)
+			occ_shutdown_sysfs(occ);
+	}
+
+	return rc;
+}
+EXPORT_SYMBOL_GPL(occ_setup);
+
+void occ_shutdown(struct occ *occ)
+{
+	mutex_lock(&occ->lock);
+
+	occ_shutdown_sysfs(occ);
+
+	if (occ->hwmon)
+		hwmon_device_unregister(occ->hwmon);
+	occ->hwmon = NULL;
+
+	mutex_unlock(&occ->lock);
+}
+EXPORT_SYMBOL_GPL(occ_shutdown);
+
+MODULE_AUTHOR("Eddie James <eajames@linux.ibm.com>");
+MODULE_DESCRIPTION("Common OCC hwmon code");
+MODULE_LICENSE("GPL");
diff --git a/drivers/hwmon/occ/common.h b/drivers/hwmon/occ/common.h
new file mode 100644
index 000000000..7ac4b2feb
--- /dev/null
+++ b/drivers/hwmon/occ/common.h
@@ -0,0 +1,136 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/* Copyright IBM Corp 2019 */
+
+#ifndef OCC_COMMON_H
+#define OCC_COMMON_H
+
+#include <linux/hwmon-sysfs.h>
+#include <linux/mutex.h>
+#include <linux/sysfs.h>
+
+struct device;
+
+#define OCC_RESP_DATA_BYTES		4089
+
+/*
+ * Same response format for all OCC versions.
+ * Allocate the largest possible response.
+ */
+struct occ_response {
+	u8 seq_no;
+	u8 cmd_type;
+	u8 return_status;
+	__be16 data_length;
+	u8 data[OCC_RESP_DATA_BYTES];
+	__be16 checksum;
+} __packed;
+
+struct occ_sensor_data_block_header {
+	u8 eye_catcher[4];
+	u8 reserved;
+	u8 sensor_format;
+	u8 sensor_length;
+	u8 num_sensors;
+} __packed;
+
+struct occ_sensor_data_block {
+	struct occ_sensor_data_block_header header;
+	u32 data;
+} __packed;
+
+struct occ_poll_response_header {
+	u8 status;
+	u8 ext_status;
+	u8 occs_present;
+	u8 config_data;
+	u8 occ_state;
+	u8 mode;
+	u8 ips_status;
+	u8 error_log_id;
+	__be32 error_log_start_address;
+	__be16 error_log_length;
+	u16 reserved;
+	u8 occ_code_level[16];
+	u8 eye_catcher[6];
+	u8 num_sensor_data_blocks;
+	u8 sensor_data_block_header_version;
+} __packed;
+
+struct occ_poll_response {
+	struct occ_poll_response_header header;
+	struct occ_sensor_data_block block;
+} __packed;
+
+struct occ_sensor {
+	u8 num_sensors;
+	u8 version;
+	void *data;	/* pointer to sensor data start within response */
+};
+
+/*
+ * OCC only provides one sensor data block of each type, but any number of
+ * sensors within that block.
+ */
+struct occ_sensors {
+	struct occ_sensor temp;
+	struct occ_sensor freq;
+	struct occ_sensor power;
+	struct occ_sensor caps;
+	struct occ_sensor extended;
+};
+
+/*
+ * Use our own attribute struct so we can dynamically allocate space for the
+ * name.
+ */
+struct occ_attribute {
+	char name[32];
+	struct sensor_device_attribute_2 sensor;
+};
+
+struct occ {
+	struct device *bus_dev;
+
+	struct occ_response resp;
+	struct occ_sensors sensors;
+
+	int powr_sample_time_us;	/* average power sample time */
+	u8 poll_cmd_data;		/* to perform OCC poll command */
+	int (*send_cmd)(struct occ *occ, u8 *cmd, size_t len, void *resp,
+			size_t resp_len);
+
+	unsigned long next_update;
+	struct mutex lock;		/* lock OCC access */
+
+	struct device *hwmon;
+	struct occ_attribute *attrs;
+	struct attribute_group group;
+	const struct attribute_group *groups[2];
+
+	bool active;
+	int error;                      /* final transfer error after retry */
+	int last_error;			/* latest transfer error */
+	unsigned int error_count;       /* number of xfr errors observed */
+	unsigned long last_safe;        /* time OCC entered "safe" state */
+
+	/*
+	 * Store the previous state data for comparison in order to notify
+	 * sysfs readers of state changes.
+	 */
+	int prev_error;
+	u8 prev_stat;
+	u8 prev_ext_stat;
+	u8 prev_occs_present;
+	u8 prev_ips_status;
+	u8 prev_mode;
+};
+
+int occ_active(struct occ *occ, bool active);
+int occ_setup(struct occ *occ);
+int occ_setup_sysfs(struct occ *occ);
+void occ_shutdown(struct occ *occ);
+void occ_shutdown_sysfs(struct occ *occ);
+void occ_sysfs_poll_done(struct occ *occ);
+int occ_update_response(struct occ *occ);
+
+#endif /* OCC_COMMON_H */
diff --git a/drivers/hwmon/occ/p8_i2c.c b/drivers/hwmon/occ/p8_i2c.c
new file mode 100644
index 000000000..9e1744fcc
--- /dev/null
+++ b/drivers/hwmon/occ/p8_i2c.c
@@ -0,0 +1,257 @@
+// SPDX-License-Identifier: GPL-2.0+
+// Copyright IBM Corp 2019
+
+#include <linux/device.h>
+#include <linux/errno.h>
+#include <linux/fsi-occ.h>
+#include <linux/i2c.h>
+#include <linux/jiffies.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <asm/unaligned.h>
+
+#include "common.h"
+
+#define OCC_TIMEOUT_MS			1000
+#define OCC_CMD_IN_PRG_WAIT_MS		50
+
+/* OCB (on-chip control bridge - interface to OCC) registers */
+#define OCB_DATA1			0x6B035
+#define OCB_ADDR			0x6B070
+#define OCB_DATA3			0x6B075
+
+/* OCC SRAM address space */
+#define OCC_SRAM_ADDR_CMD		0xFFFF6000
+#define OCC_SRAM_ADDR_RESP		0xFFFF7000
+
+#define OCC_DATA_ATTN			0x20010000
+
+struct p8_i2c_occ {
+	struct occ occ;
+	struct i2c_client *client;
+};
+
+#define to_p8_i2c_occ(x)	container_of((x), struct p8_i2c_occ, occ)
+
+static int p8_i2c_occ_getscom(struct i2c_client *client, u32 address, u8 *data)
+{
+	ssize_t rc;
+	__be64 buf;
+	struct i2c_msg msgs[2];
+
+	/* p8 i2c slave requires shift */
+	address <<= 1;
+
+	msgs[0].addr = client->addr;
+	msgs[0].flags = client->flags & I2C_M_TEN;
+	msgs[0].len = sizeof(u32);
+	/* address is a scom address; bus-endian */
+	msgs[0].buf = (char *)&address;
+
+	/* data from OCC is big-endian */
+	msgs[1].addr = client->addr;
+	msgs[1].flags = (client->flags & I2C_M_TEN) | I2C_M_RD;
+	msgs[1].len = sizeof(u64);
+	msgs[1].buf = (char *)&buf;
+
+	rc = i2c_transfer(client->adapter, msgs, 2);
+	if (rc < 0)
+		return rc;
+
+	*(u64 *)data = be64_to_cpu(buf);
+
+	return 0;
+}
+
+static int p8_i2c_occ_putscom(struct i2c_client *client, u32 address, u8 *data)
+{
+	u32 buf[3];
+	ssize_t rc;
+
+	/* p8 i2c slave requires shift */
+	address <<= 1;
+
+	/* address is bus-endian; data passed through from user as-is */
+	buf[0] = address;
+	memcpy(&buf[1], &data[4], sizeof(u32));
+	memcpy(&buf[2], data, sizeof(u32));
+
+	rc = i2c_master_send(client, (const char *)buf, sizeof(buf));
+	if (rc < 0)
+		return rc;
+	else if (rc != sizeof(buf))
+		return -EIO;
+
+	return 0;
+}
+
+static int p8_i2c_occ_putscom_u32(struct i2c_client *client, u32 address,
+				  u32 data0, u32 data1)
+{
+	u8 buf[8];
+
+	memcpy(buf, &data0, 4);
+	memcpy(buf + 4, &data1, 4);
+
+	return p8_i2c_occ_putscom(client, address, buf);
+}
+
+static int p8_i2c_occ_putscom_be(struct i2c_client *client, u32 address,
+				 u8 *data, size_t len)
+{
+	__be32 data0 = 0, data1 = 0;
+
+	memcpy(&data0, data, min_t(size_t, len, 4));
+	if (len > 4) {
+		len -= 4;
+		memcpy(&data1, data + 4, min_t(size_t, len, 4));
+	}
+
+	return p8_i2c_occ_putscom_u32(client, address, be32_to_cpu(data0),
+				      be32_to_cpu(data1));
+}
+
+static int p8_i2c_occ_send_cmd(struct occ *occ, u8 *cmd, size_t len,
+			       void *resp, size_t resp_len)
+{
+	int i, rc;
+	unsigned long start;
+	u16 data_length;
+	const unsigned long timeout = msecs_to_jiffies(OCC_TIMEOUT_MS);
+	const long wait_time = msecs_to_jiffies(OCC_CMD_IN_PRG_WAIT_MS);
+	struct p8_i2c_occ *ctx = to_p8_i2c_occ(occ);
+	struct i2c_client *client = ctx->client;
+	struct occ_response *or = (struct occ_response *)resp;
+
+	start = jiffies;
+
+	/* set sram address for command */
+	rc = p8_i2c_occ_putscom_u32(client, OCB_ADDR, OCC_SRAM_ADDR_CMD, 0);
+	if (rc)
+		return rc;
+
+	/* write command (expected to already be BE), we need bus-endian... */
+	rc = p8_i2c_occ_putscom_be(client, OCB_DATA3, cmd, len);
+	if (rc)
+		return rc;
+
+	/* trigger OCC attention */
+	rc = p8_i2c_occ_putscom_u32(client, OCB_DATA1, OCC_DATA_ATTN, 0);
+	if (rc)
+		return rc;
+
+	do {
+		/* set sram address for response */
+		rc = p8_i2c_occ_putscom_u32(client, OCB_ADDR,
+					    OCC_SRAM_ADDR_RESP, 0);
+		if (rc)
+			return rc;
+
+		rc = p8_i2c_occ_getscom(client, OCB_DATA3, (u8 *)resp);
+		if (rc)
+			return rc;
+
+		/* wait for OCC */
+		if (or->return_status == OCC_RESP_CMD_IN_PRG) {
+			rc = -EALREADY;
+
+			if (time_after(jiffies, start + timeout))
+				break;
+
+			set_current_state(TASK_INTERRUPTIBLE);
+			schedule_timeout(wait_time);
+		}
+	} while (rc);
+
+	/* check the OCC response */
+	switch (or->return_status) {
+	case OCC_RESP_CMD_IN_PRG:
+		rc = -ETIMEDOUT;
+		break;
+	case OCC_RESP_SUCCESS:
+		rc = 0;
+		break;
+	case OCC_RESP_CMD_INVAL:
+	case OCC_RESP_CMD_LEN_INVAL:
+	case OCC_RESP_DATA_INVAL:
+	case OCC_RESP_CHKSUM_ERR:
+		rc = -EINVAL;
+		break;
+	case OCC_RESP_INT_ERR:
+	case OCC_RESP_BAD_STATE:
+	case OCC_RESP_CRIT_EXCEPT:
+	case OCC_RESP_CRIT_INIT:
+	case OCC_RESP_CRIT_WATCHDOG:
+	case OCC_RESP_CRIT_OCB:
+	case OCC_RESP_CRIT_HW:
+		rc = -EREMOTEIO;
+		break;
+	default:
+		rc = -EPROTO;
+	}
+
+	if (rc < 0)
+		return rc;
+
+	data_length = get_unaligned_be16(&or->data_length);
+	if ((data_length + 7) > resp_len)
+		return -EMSGSIZE;
+
+	/* fetch the rest of the response data */
+	for (i = 8; i < data_length + 7; i += 8) {
+		rc = p8_i2c_occ_getscom(client, OCB_DATA3, ((u8 *)resp) + i);
+		if (rc)
+			return rc;
+	}
+
+	return 0;
+}
+
+static int p8_i2c_occ_probe(struct i2c_client *client)
+{
+	struct occ *occ;
+	struct p8_i2c_occ *ctx = devm_kzalloc(&client->dev, sizeof(*ctx),
+					      GFP_KERNEL);
+	if (!ctx)
+		return -ENOMEM;
+
+	ctx->client = client;
+	occ = &ctx->occ;
+	occ->bus_dev = &client->dev;
+	dev_set_drvdata(&client->dev, occ);
+
+	occ->powr_sample_time_us = 250;
+	occ->poll_cmd_data = 0x10;		/* P8 OCC poll data */
+	occ->send_cmd = p8_i2c_occ_send_cmd;
+
+	return occ_setup(occ);
+}
+
+static void p8_i2c_occ_remove(struct i2c_client *client)
+{
+	struct occ *occ = dev_get_drvdata(&client->dev);
+
+	occ_shutdown(occ);
+}
+
+static const struct of_device_id p8_i2c_occ_of_match[] = {
+	{ .compatible = "ibm,p8-occ-hwmon" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, p8_i2c_occ_of_match);
+
+static struct i2c_driver p8_i2c_occ_driver = {
+	.class = I2C_CLASS_HWMON,
+	.driver = {
+		.name = "occ-hwmon",
+		.of_match_table = p8_i2c_occ_of_match,
+	},
+	.probe_new = p8_i2c_occ_probe,
+	.remove = p8_i2c_occ_remove,
+};
+
+module_i2c_driver(p8_i2c_occ_driver);
+
+MODULE_AUTHOR("Eddie James <eajames@linux.ibm.com>");
+MODULE_DESCRIPTION("BMC P8 OCC hwmon driver");
+MODULE_LICENSE("GPL");
diff --git a/drivers/hwmon/occ/p9_sbe.c b/drivers/hwmon/occ/p9_sbe.c
new file mode 100644
index 000000000..96521363b
--- /dev/null
+++ b/drivers/hwmon/occ/p9_sbe.c
@@ -0,0 +1,205 @@
+// SPDX-License-Identifier: GPL-2.0+
+// Copyright IBM Corp 2019
+
+#include <linux/device.h>
+#include <linux/errno.h>
+#include <linux/slab.h>
+#include <linux/fsi-occ.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+#include <linux/mutex.h>
+#include <linux/platform_device.h>
+#include <linux/string.h>
+#include <linux/sysfs.h>
+
+#include "common.h"
+
+#define OCC_CHECKSUM_RETRIES	3
+
+struct p9_sbe_occ {
+	struct occ occ;
+	bool sbe_error;
+	void *ffdc;
+	size_t ffdc_len;
+	size_t ffdc_size;
+	struct mutex sbe_error_lock;	/* lock access to ffdc data */
+	struct device *sbe;
+};
+
+#define to_p9_sbe_occ(x)	container_of((x), struct p9_sbe_occ, occ)
+
+static ssize_t ffdc_read(struct file *filp, struct kobject *kobj,
+			 struct bin_attribute *battr, char *buf, loff_t pos,
+			 size_t count)
+{
+	ssize_t rc = 0;
+	struct occ *occ = dev_get_drvdata(kobj_to_dev(kobj));
+	struct p9_sbe_occ *ctx = to_p9_sbe_occ(occ);
+
+	mutex_lock(&ctx->sbe_error_lock);
+	if (ctx->sbe_error) {
+		rc = memory_read_from_buffer(buf, count, &pos, ctx->ffdc,
+					     ctx->ffdc_len);
+		if (pos >= ctx->ffdc_len)
+			ctx->sbe_error = false;
+	}
+	mutex_unlock(&ctx->sbe_error_lock);
+
+	return rc;
+}
+static BIN_ATTR_RO(ffdc, OCC_MAX_RESP_WORDS * 4);
+
+static bool p9_sbe_occ_save_ffdc(struct p9_sbe_occ *ctx, const void *resp,
+				 size_t resp_len)
+{
+	bool notify = false;
+
+	mutex_lock(&ctx->sbe_error_lock);
+	if (!ctx->sbe_error) {
+		if (resp_len > ctx->ffdc_size) {
+			kvfree(ctx->ffdc);
+			ctx->ffdc = kvmalloc(resp_len, GFP_KERNEL);
+			if (!ctx->ffdc) {
+				ctx->ffdc_len = 0;
+				ctx->ffdc_size = 0;
+				goto done;
+			}
+
+			ctx->ffdc_size = resp_len;
+		}
+
+		notify = true;
+		ctx->sbe_error = true;
+		ctx->ffdc_len = resp_len;
+		memcpy(ctx->ffdc, resp, resp_len);
+	}
+
+done:
+	mutex_unlock(&ctx->sbe_error_lock);
+	return notify;
+}
+
+static int p9_sbe_occ_send_cmd(struct occ *occ, u8 *cmd, size_t len,
+			       void *resp, size_t resp_len)
+{
+	size_t original_resp_len = resp_len;
+	struct p9_sbe_occ *ctx = to_p9_sbe_occ(occ);
+	int rc, i;
+
+	for (i = 0; i < OCC_CHECKSUM_RETRIES; ++i) {
+		rc = fsi_occ_submit(ctx->sbe, cmd, len, resp, &resp_len);
+		if (rc >= 0)
+			break;
+		if (resp_len) {
+			if (p9_sbe_occ_save_ffdc(ctx, resp, resp_len))
+				sysfs_notify(&occ->bus_dev->kobj, NULL,
+					     bin_attr_ffdc.attr.name);
+			return rc;
+		}
+		if (rc != -EBADE)
+			return rc;
+		resp_len = original_resp_len;
+	}
+
+	switch (((struct occ_response *)resp)->return_status) {
+	case OCC_RESP_CMD_IN_PRG:
+		rc = -ETIMEDOUT;
+		break;
+	case OCC_RESP_SUCCESS:
+		rc = 0;
+		break;
+	case OCC_RESP_CMD_INVAL:
+	case OCC_RESP_CMD_LEN_INVAL:
+	case OCC_RESP_DATA_INVAL:
+	case OCC_RESP_CHKSUM_ERR:
+		rc = -EINVAL;
+		break;
+	case OCC_RESP_INT_ERR:
+	case OCC_RESP_BAD_STATE:
+	case OCC_RESP_CRIT_EXCEPT:
+	case OCC_RESP_CRIT_INIT:
+	case OCC_RESP_CRIT_WATCHDOG:
+	case OCC_RESP_CRIT_OCB:
+	case OCC_RESP_CRIT_HW:
+		rc = -EREMOTEIO;
+		break;
+	default:
+		rc = -EPROTO;
+	}
+
+	return rc;
+}
+
+static int p9_sbe_occ_probe(struct platform_device *pdev)
+{
+	int rc;
+	struct occ *occ;
+	struct p9_sbe_occ *ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx),
+					      GFP_KERNEL);
+	if (!ctx)
+		return -ENOMEM;
+
+	mutex_init(&ctx->sbe_error_lock);
+
+	ctx->sbe = pdev->dev.parent;
+	occ = &ctx->occ;
+	occ->bus_dev = &pdev->dev;
+	platform_set_drvdata(pdev, occ);
+
+	occ->powr_sample_time_us = 500;
+	occ->poll_cmd_data = 0x20;		/* P9 OCC poll data */
+	occ->send_cmd = p9_sbe_occ_send_cmd;
+
+	rc = occ_setup(occ);
+	if (rc == -ESHUTDOWN)
+		rc = -ENODEV;	/* Host is shutdown, don't spew errors */
+
+	if (!rc) {
+		rc = device_create_bin_file(occ->bus_dev, &bin_attr_ffdc);
+		if (rc) {
+			dev_warn(occ->bus_dev,
+				 "failed to create SBE error ffdc file\n");
+			rc = 0;
+		}
+	}
+
+	return rc;
+}
+
+static int p9_sbe_occ_remove(struct platform_device *pdev)
+{
+	struct occ *occ = platform_get_drvdata(pdev);
+	struct p9_sbe_occ *ctx = to_p9_sbe_occ(occ);
+
+	device_remove_bin_file(occ->bus_dev, &bin_attr_ffdc);
+
+	ctx->sbe = NULL;
+	occ_shutdown(occ);
+
+	kvfree(ctx->ffdc);
+
+	return 0;
+}
+
+static const struct of_device_id p9_sbe_occ_of_match[] = {
+	{ .compatible = "ibm,p9-occ-hwmon" },
+	{ .compatible = "ibm,p10-occ-hwmon" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, p9_sbe_occ_of_match);
+
+static struct platform_driver p9_sbe_occ_driver = {
+	.driver = {
+		.name = "occ-hwmon",
+		.of_match_table = p9_sbe_occ_of_match,
+	},
+	.probe	= p9_sbe_occ_probe,
+	.remove = p9_sbe_occ_remove,
+};
+
+module_platform_driver(p9_sbe_occ_driver);
+
+MODULE_AUTHOR("Eddie James <eajames@linux.ibm.com>");
+MODULE_DESCRIPTION("BMC P9 OCC hwmon driver");
+MODULE_LICENSE("GPL");
diff --git a/drivers/hwmon/occ/sysfs.c b/drivers/hwmon/occ/sysfs.c
new file mode 100644
index 000000000..2317301fc
--- /dev/null
+++ b/drivers/hwmon/occ/sysfs.c
@@ -0,0 +1,257 @@
+// SPDX-License-Identifier: GPL-2.0+
+// Copyright IBM Corp 2019
+
+#include <linux/bitops.h>
+#include <linux/device.h>
+#include <linux/export.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/kernel.h>
+#include <linux/kstrtox.h>
+#include <linux/sysfs.h>
+
+#include "common.h"
+
+/* OCC status register */
+#define OCC_STAT_MASTER			BIT(7)
+
+/* OCC extended status register */
+#define OCC_EXT_STAT_DVFS_OT		BIT(7)
+#define OCC_EXT_STAT_DVFS_POWER		BIT(6)
+#define OCC_EXT_STAT_MEM_THROTTLE	BIT(5)
+#define OCC_EXT_STAT_QUICK_DROP		BIT(4)
+#define OCC_EXT_STAT_DVFS_VDD		BIT(3)
+#define OCC_EXT_STAT_GPU_THROTTLE	GENMASK(2, 0)
+
+static ssize_t occ_active_store(struct device *dev,
+				struct device_attribute *attr,
+				const char *buf, size_t count)
+{
+	int rc;
+	bool active;
+	struct occ *occ = dev_get_drvdata(dev);
+
+	rc = kstrtobool(buf, &active);
+	if (rc)
+		return rc;
+
+	rc = occ_active(occ, active);
+	if (rc)
+		return rc;
+
+	return count;
+}
+
+static ssize_t occ_sysfs_show(struct device *dev,
+			      struct device_attribute *attr, char *buf)
+{
+	int rc;
+	int val = 0;
+	struct occ *occ = dev_get_drvdata(dev);
+	struct occ_poll_response_header *header;
+	struct sensor_device_attribute *sattr = to_sensor_dev_attr(attr);
+
+	if (occ->active) {
+		rc = occ_update_response(occ);
+		if (rc)
+			return rc;
+
+		header = (struct occ_poll_response_header *)occ->resp.data;
+
+		switch (sattr->index) {
+		case 0:
+			val = !!(header->status & OCC_STAT_MASTER);
+			break;
+		case 1:
+			val = 1;
+			break;
+		case 2:
+			val = !!(header->ext_status & OCC_EXT_STAT_DVFS_OT);
+			break;
+		case 3:
+			val = !!(header->ext_status & OCC_EXT_STAT_DVFS_POWER);
+			break;
+		case 4:
+			val = !!(header->ext_status &
+				 OCC_EXT_STAT_MEM_THROTTLE);
+			break;
+		case 5:
+			val = !!(header->ext_status & OCC_EXT_STAT_QUICK_DROP);
+			break;
+		case 6:
+			val = header->occ_state;
+			break;
+		case 7:
+			if (header->status & OCC_STAT_MASTER)
+				val = hweight8(header->occs_present);
+			else
+				val = 1;
+			break;
+		case 8:
+			val = header->ips_status;
+			break;
+		case 9:
+			val = header->mode;
+			break;
+		case 10:
+			val = !!(header->ext_status & OCC_EXT_STAT_DVFS_VDD);
+			break;
+		case 11:
+			val = header->ext_status & OCC_EXT_STAT_GPU_THROTTLE;
+			break;
+		default:
+			return -EINVAL;
+		}
+	} else {
+		if (sattr->index == 1)
+			val = 0;
+		else if (sattr->index <= 11)
+			val = -ENODATA;
+		else
+			return -EINVAL;
+	}
+
+	return sysfs_emit(buf, "%d\n", val);
+}
+
+static ssize_t occ_error_show(struct device *dev,
+			      struct device_attribute *attr, char *buf)
+{
+	struct occ *occ = dev_get_drvdata(dev);
+
+	occ_update_response(occ);
+
+	return sysfs_emit(buf, "%d\n", occ->error);
+}
+
+static SENSOR_DEVICE_ATTR(occ_master, 0444, occ_sysfs_show, NULL, 0);
+static SENSOR_DEVICE_ATTR(occ_active, 0644, occ_sysfs_show, occ_active_store,
+			  1);
+static SENSOR_DEVICE_ATTR(occ_dvfs_overtemp, 0444, occ_sysfs_show, NULL, 2);
+static SENSOR_DEVICE_ATTR(occ_dvfs_power, 0444, occ_sysfs_show, NULL, 3);
+static SENSOR_DEVICE_ATTR(occ_mem_throttle, 0444, occ_sysfs_show, NULL, 4);
+static SENSOR_DEVICE_ATTR(occ_quick_pwr_drop, 0444, occ_sysfs_show, NULL, 5);
+static SENSOR_DEVICE_ATTR(occ_state, 0444, occ_sysfs_show, NULL, 6);
+static SENSOR_DEVICE_ATTR(occs_present, 0444, occ_sysfs_show, NULL, 7);
+static SENSOR_DEVICE_ATTR(occ_ips_status, 0444, occ_sysfs_show, NULL, 8);
+static SENSOR_DEVICE_ATTR(occ_mode, 0444, occ_sysfs_show, NULL, 9);
+static SENSOR_DEVICE_ATTR(occ_dvfs_vdd, 0444, occ_sysfs_show, NULL, 10);
+static SENSOR_DEVICE_ATTR(occ_gpu_throttle, 0444, occ_sysfs_show, NULL, 11);
+static DEVICE_ATTR_RO(occ_error);
+
+static struct attribute *occ_attributes[] = {
+	&sensor_dev_attr_occ_master.dev_attr.attr,
+	&sensor_dev_attr_occ_active.dev_attr.attr,
+	&sensor_dev_attr_occ_dvfs_overtemp.dev_attr.attr,
+	&sensor_dev_attr_occ_dvfs_power.dev_attr.attr,
+	&sensor_dev_attr_occ_mem_throttle.dev_attr.attr,
+	&sensor_dev_attr_occ_quick_pwr_drop.dev_attr.attr,
+	&sensor_dev_attr_occ_state.dev_attr.attr,
+	&sensor_dev_attr_occs_present.dev_attr.attr,
+	&sensor_dev_attr_occ_ips_status.dev_attr.attr,
+	&sensor_dev_attr_occ_mode.dev_attr.attr,
+	&sensor_dev_attr_occ_dvfs_vdd.dev_attr.attr,
+	&sensor_dev_attr_occ_gpu_throttle.dev_attr.attr,
+	&dev_attr_occ_error.attr,
+	NULL
+};
+
+static const struct attribute_group occ_sysfs = {
+	.attrs = occ_attributes,
+};
+
+void occ_sysfs_poll_done(struct occ *occ)
+{
+	const char *name;
+	struct occ_poll_response_header *header =
+		(struct occ_poll_response_header *)occ->resp.data;
+
+	/*
+	 * On the first poll response, we haven't yet created the sysfs
+	 * attributes, so don't make any notify calls.
+	 */
+	if (!occ->active)
+		goto done;
+
+	if ((header->status & OCC_STAT_MASTER) !=
+	    (occ->prev_stat & OCC_STAT_MASTER)) {
+		name = sensor_dev_attr_occ_master.dev_attr.attr.name;
+		sysfs_notify(&occ->bus_dev->kobj, NULL, name);
+	}
+
+	if ((header->ext_status & OCC_EXT_STAT_DVFS_OT) !=
+	    (occ->prev_ext_stat & OCC_EXT_STAT_DVFS_OT)) {
+		name = sensor_dev_attr_occ_dvfs_overtemp.dev_attr.attr.name;
+		sysfs_notify(&occ->bus_dev->kobj, NULL, name);
+	}
+
+	if ((header->ext_status & OCC_EXT_STAT_DVFS_POWER) !=
+	    (occ->prev_ext_stat & OCC_EXT_STAT_DVFS_POWER)) {
+		name = sensor_dev_attr_occ_dvfs_power.dev_attr.attr.name;
+		sysfs_notify(&occ->bus_dev->kobj, NULL, name);
+	}
+
+	if ((header->ext_status & OCC_EXT_STAT_MEM_THROTTLE) !=
+	    (occ->prev_ext_stat & OCC_EXT_STAT_MEM_THROTTLE)) {
+		name = sensor_dev_attr_occ_mem_throttle.dev_attr.attr.name;
+		sysfs_notify(&occ->bus_dev->kobj, NULL, name);
+	}
+
+	if ((header->ext_status & OCC_EXT_STAT_QUICK_DROP) !=
+	    (occ->prev_ext_stat & OCC_EXT_STAT_QUICK_DROP)) {
+		name = sensor_dev_attr_occ_quick_pwr_drop.dev_attr.attr.name;
+		sysfs_notify(&occ->bus_dev->kobj, NULL, name);
+	}
+
+	if ((header->ext_status & OCC_EXT_STAT_DVFS_VDD) !=
+	    (occ->prev_ext_stat & OCC_EXT_STAT_DVFS_VDD)) {
+		name = sensor_dev_attr_occ_dvfs_vdd.dev_attr.attr.name;
+		sysfs_notify(&occ->bus_dev->kobj, NULL, name);
+	}
+
+	if ((header->ext_status & OCC_EXT_STAT_GPU_THROTTLE) !=
+	    (occ->prev_ext_stat & OCC_EXT_STAT_GPU_THROTTLE)) {
+		name = sensor_dev_attr_occ_gpu_throttle.dev_attr.attr.name;
+		sysfs_notify(&occ->bus_dev->kobj, NULL, name);
+	}
+
+	if ((header->status & OCC_STAT_MASTER) &&
+	    header->occs_present != occ->prev_occs_present) {
+		name = sensor_dev_attr_occs_present.dev_attr.attr.name;
+		sysfs_notify(&occ->bus_dev->kobj, NULL, name);
+	}
+
+	if (header->ips_status != occ->prev_ips_status) {
+		name = sensor_dev_attr_occ_ips_status.dev_attr.attr.name;
+		sysfs_notify(&occ->bus_dev->kobj, NULL, name);
+	}
+
+	if (header->mode != occ->prev_mode) {
+		name = sensor_dev_attr_occ_mode.dev_attr.attr.name;
+		sysfs_notify(&occ->bus_dev->kobj, NULL, name);
+	}
+
+	if (occ->error && occ->error != occ->prev_error) {
+		name = dev_attr_occ_error.attr.name;
+		sysfs_notify(&occ->bus_dev->kobj, NULL, name);
+	}
+
+	/* no notifications for OCC state; doesn't indicate error condition */
+
+done:
+	occ->prev_error = occ->error;
+	occ->prev_stat = header->status;
+	occ->prev_ext_stat = header->ext_status;
+	occ->prev_occs_present = header->occs_present;
+	occ->prev_ips_status = header->ips_status;
+	occ->prev_mode = header->mode;
+}
+
+int occ_setup_sysfs(struct occ *occ)
+{
+	return sysfs_create_group(&occ->bus_dev->kobj, &occ_sysfs);
+}
+
+void occ_shutdown_sysfs(struct occ *occ)
+{
+	sysfs_remove_group(&occ->bus_dev->kobj, &occ_sysfs);
+}