From: eajames.ibm@gmail.com
To: openbmc@lists.ozlabs.org
Cc: "Edward A. James" <eajames@us.ibm.com>
Subject: [RFC linux v3 1/4] Revert "hwmon: Add Power8 OCC hwmon driver"
Date: Wed, 12 Oct 2016 17:42:22 -0500
Message-Id: <1476312142-20064-1-git-send-email-eajames.ibm@gmail.com>
Precedence: list

From: "Edward A. James" <eajames@us.ibm.com>

This reverts commit 7cddcb99cb42cc4a1d72f2d73a78394bb2dcb0f1.
---
 .../devicetree/bindings/i2c/i2c-ibm-occ.txt        |   13 -
 drivers/hwmon/Kconfig                              |   13 -
 drivers/hwmon/Makefile                             |    1 -
 drivers/hwmon/power8_occ_i2c.c                     | 1254 --------------------
 4 files changed, 1281 deletions(-)
 delete mode 100644 Documentation/devicetree/bindings/i2c/i2c-ibm-occ.txt
 delete mode 100644 drivers/hwmon/power8_occ_i2c.c

diff --git a/Documentation/devicetree/bindings/i2c/i2c-ibm-occ.txt b/Documentation/devicetree/bindings/i2c/i2c-ibm-occ.txt
deleted file mode 100644
index 9aab2df..0000000
--- a/Documentation/devicetree/bindings/i2c/i2c-ibm-occ.txt
+++ /dev/null
@@ -1,13 +0,0 @@
-HWMON i2c driver for IBM POWER CPU OCC (On Chip Controller)
-
-Required properties:
- - compatible: must be "ibm,power8-occ-i2c"
- - reg: physical address
-
-Example:
-i2c3: i2c-bus@100 {
-	occ@50 {
-		compatible = "ibm,occ-i2c";
-		reg = <0x50>;
-	};
-};
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index d4de8d5..367496c 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -1226,19 +1226,6 @@ config SENSORS_NSA320
 	  This driver can also be built as a module. If so, the module
 	  will be called nsa320-hwmon.
 
-config SENSORS_POWER8_OCC_I2C
-	tristate "Power8 On Chip Controller i2c driver"
-	depends on I2C
-	help
-	  If you say yes here you get support to monitor Power8 CPU
-	  sensors via the On Chip Controller (OCC) over the i2c bus.
-
-	  Generally this is used by management controllers such as a BMC
-	  on an OpenPower system.
-
-	  This driver can also be built as a module. If so, the module
-	  will be called power8_occ_i2c.
-
 config SENSORS_PCF8591
 	tristate "Philips PCF8591 ADC/DAC"
 	depends on I2C
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index 4455478..d7ccb02 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -128,7 +128,6 @@ obj-$(CONFIG_SENSORS_NCT7802)	+= nct7802.o
 obj-$(CONFIG_SENSORS_NCT7904)	+= nct7904.o
 obj-$(CONFIG_SENSORS_NSA320)	+= nsa320-hwmon.o
 obj-$(CONFIG_SENSORS_NTC_THERMISTOR)	+= ntc_thermistor.o
-obj-$(CONFIG_SENSORS_POWER8_OCC_I2C)	+= power8_occ_i2c.o
 obj-$(CONFIG_SENSORS_PC87360)	+= pc87360.o
 obj-$(CONFIG_SENSORS_PC87427)	+= pc87427.o
 obj-$(CONFIG_SENSORS_PCF8591)	+= pcf8591.o
diff --git a/drivers/hwmon/power8_occ_i2c.c b/drivers/hwmon/power8_occ_i2c.c
deleted file mode 100644
index 6de0e76..0000000
--- a/drivers/hwmon/power8_occ_i2c.c
+++ /dev/null
@@ -1,1254 +0,0 @@
-/*
- * OCC HWMON driver - read IBM Power8 On Chip Controller sensor data via
- * i2c.
- *
- * Copyright 2015 IBM Corp.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- */
-
-#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/mutex.h>
-#include <linux/of.h>
-#include <linux/delay.h>
-#include <linux/kernel.h>
-#include <linux/device.h>
-
-#define OCC_I2C_ADDR 0x50
-#define OCC_I2C_NAME "occ-i2c"
-
-#define OCC_DATA_MAX	4096 /* 4KB at most */
-/* i2c read and write occ sensors */
-#define I2C_READ_ERROR	1
-#define I2C_WRITE_ERROR	2
-
-/* Defined in POWER8 Processor Registers Specification */
-/* To generate attn to OCC */
-#define ATTN_DATA	0x0006B035
-/* For BMC to read/write SRAM */
-#define OCB_ADDRESS		0x0006B070
-#define OCB_DATA		0x0006B075
-#define OCB_STATUS_CONTROL_AND	0x0006B072
-#define OCB_STATUS_CONTROL_OR	0x0006B073
-/* See definition in:
- * https://github.com/open-power/docs/blob/master/occ/OCC_OpenPwr_FW_Interfaces.pdf
- */
-#define OCC_COMMAND_ADDR	0xFFFF6000
-#define OCC_RESPONSE_ADDR	0xFFFF7000
-
-#define MAX_SENSOR_ATTR_LEN	32
-
-enum sensor_t {
-	freq,
-	temp,
-	power,
-	caps,
-	MAX_OCC_SENSOR_TYPE
-};
-
-/* OCC sensor data format */
-struct occ_sensor {
-	uint16_t sensor_id;
-	uint16_t value;
-};
-
-struct power_sensor {
-	uint16_t sensor_id;
-	uint32_t update_tag;
-	uint32_t accumulator;
-	uint16_t value;
-};
-
-struct caps_sensor {
-	uint16_t curr_powercap;
-	uint16_t curr_powerreading;
-	uint16_t norm_powercap;
-	uint16_t max_powercap;
-	uint16_t min_powercap;
-	uint16_t user_powerlimit;
-};
-
-struct sensor_data_block {
-	uint8_t sensor_type[4];
-	uint8_t reserved0;
-	uint8_t sensor_format;
-	uint8_t sensor_length;
-	uint8_t sensor_num;
-	struct occ_sensor *sensor;
-	struct power_sensor *power;
-	struct caps_sensor *caps;
-};
-
-struct occ_poll_header {
-	uint8_t status;
-	uint8_t ext_status;
-	uint8_t occs_present;
-	uint8_t config;
-	uint8_t occ_state;
-	uint8_t reserved0;
-	uint8_t reserved1;
-	uint8_t error_log_id;
-	uint32_t error_log_addr_start;
-	uint16_t error_log_length;
-	uint8_t reserved2;
-	uint8_t reserved3;
-	uint8_t occ_code_level[16];
-	uint8_t sensor_eye_catcher[6];
-	uint8_t sensor_block_num;
-	uint8_t sensor_data_version;
-};
-
-struct occ_response {
-	uint8_t sequence_num;
-	uint8_t cmd_type;
-	uint8_t rtn_status;
-	uint16_t data_length;
-	struct occ_poll_header header;
-	struct sensor_data_block *blocks;
-	uint16_t chk_sum;
-	int sensor_block_id[MAX_OCC_SENSOR_TYPE];
-};
-
-struct sensor_attr_data {
-	enum sensor_t type;
-	uint32_t hwmon_index;
-	uint32_t attr_id;
-	char name[MAX_SENSOR_ATTR_LEN];
-	struct device_attribute dev_attr;
-};
-
-struct sensor_group {
-	char *name;
-	struct sensor_attr_data *sattr;
-	struct attribute_group group;
-};
-
-/* data private to each client */
-struct occ_drv_data {
-	struct i2c_client	*client;
-	struct device		*hwmon_dev;
-	struct mutex		update_lock;
-	bool			valid;
-	unsigned long		last_updated;
-	/* Minimum timer interval for sampling In jiffies */
-	unsigned long		update_interval;
-	unsigned long		occ_online;
-	uint16_t		user_powercap;
-	struct occ_response	occ_resp;
-	struct sensor_group	sensor_groups[MAX_OCC_SENSOR_TYPE];
-};
-
-static void deinit_occ_resp_buf(struct occ_response *p)
-{
-	int i;
-
-	if (!p)
-		return;
-
-	if (!p->blocks)
-		return;
-
-	for (i = 0; i < p->header.sensor_block_num; i++) {
-		kfree(p->blocks[i].sensor);
-		kfree(p->blocks[i].power);
-		kfree(p->blocks[i].caps);
-	}
-
-	kfree(p->blocks);
-
-	memset(p, 0, sizeof(*p));
-
-	for (i = 0; i < ARRAY_SIZE(p->sensor_block_id); i++)
-		p->sensor_block_id[i] = -1;
-}
-
-static ssize_t occ_i2c_read(struct i2c_client *client, void *buf, size_t count)
-{
-	WARN_ON(count > OCC_DATA_MAX);
-
-	dev_dbg(&client->dev, "i2c_read: reading %zu bytes @0x%x.\n",
-		count, client->addr);
-	return i2c_master_recv(client, buf, count);
-}
-
-static ssize_t occ_i2c_write(struct i2c_client *client, const void *buf,
-				size_t count)
-{
-	WARN_ON(count > OCC_DATA_MAX);
-
-	dev_dbg(&client->dev, "i2c_write: writing %zu bytes @0x%x.\n",
-		count, client->addr);
-	return i2c_master_send(client, buf, count);
-}
-
-/* read 8-byte value and put into data[offset] */
-static int occ_getscomb(struct i2c_client *client, uint32_t address,
-		uint8_t *data, int offset)
-{
-	uint32_t ret;
-	char buf[8];
-	int i;
-
-	/* P8 i2c slave requires address to be shifted by 1 */
-	address = address << 1;
-
-	ret = occ_i2c_write(client, &address,
-		sizeof(address));
-
-	if (ret != sizeof(address))
-		return -I2C_WRITE_ERROR;
-
-	ret = occ_i2c_read(client, buf, sizeof(buf));
-	if (ret != sizeof(buf))
-		return -I2C_READ_ERROR;
-
-	for (i = 0; i < 8; i++)
-		data[offset + i] = buf[7 - i];
-
-	return 0;
-}
-
-static int occ_putscom(struct i2c_client *client, uint32_t address,
-		uint32_t data0, uint32_t data1)
-{
-	uint32_t buf[3];
-	uint32_t ret;
-
-	/* P8 i2c slave requires address to be shifted by 1 */
-	address = address << 1;
-
-	buf[0] = address;
-	buf[1] = data1;
-	buf[2] = data0;
-
-	ret = occ_i2c_write(client, buf, sizeof(buf));
-	if (ret != sizeof(buf))
-		return I2C_WRITE_ERROR;
-
-	return 0;
-}
-
-static void *occ_get_sensor_by_type(struct occ_response *resp, enum sensor_t t)
-{
-	void *sensor;
-
-	if (!resp->blocks)
-		return NULL;
-
-	if (resp->sensor_block_id[t] == -1)
-		return NULL;
-
-	switch (t) {
-	case temp:
-	case freq:
-		sensor = resp->blocks[resp->sensor_block_id[t]].sensor;
-		break;
-	case power:
-		sensor = resp->blocks[resp->sensor_block_id[t]].power;
-		break;
-	case caps:
-		sensor = resp->blocks[resp->sensor_block_id[t]].caps;
-		break;
-	default:
-		sensor = NULL;
-	}
-
-	return sensor;
-}
-
-static int occ_renew_sensor(struct occ_response *resp, uint8_t sensor_length,
-	uint8_t sensor_num, enum sensor_t t, int block)
-{
-	void *sensor;
-	int ret;
-
-	sensor = occ_get_sensor_by_type(resp, t);
-
-	/* empty sensor block, release older sensor data */
-	if (sensor_num == 0 || sensor_length == 0) {
-		kfree(sensor);
-		return -1;
-	}
-
-	if (!sensor || sensor_num !=
-			resp->blocks[resp->sensor_block_id[t]].sensor_num) {
-		kfree(sensor);
-		switch (t) {
-		case temp:
-		case freq:
-			resp->blocks[block].sensor =
-				kcalloc(sensor_num,
-					sizeof(struct occ_sensor), GFP_KERNEL);
-			if (!resp->blocks[block].sensor) {
-				ret = -ENOMEM;
-				goto err;
-			}
-			break;
-		case power:
-			resp->blocks[block].power =
-				kcalloc(sensor_num,
-					sizeof(struct power_sensor),
-					GFP_KERNEL);
-			if (!resp->blocks[block].power) {
-				ret = -ENOMEM;
-				goto err;
-			}
-			break;
-		case caps:
-			resp->blocks[block].caps =
-				kcalloc(sensor_num,
-					sizeof(struct caps_sensor), GFP_KERNEL);
-			if (!resp->blocks[block].caps) {
-				ret = -ENOMEM;
-				goto err;
-			}
-			break;
-		default:
-			ret = -ENOMEM;
-			goto err;
-		}
-	}
-
-	return 0;
-err:
-	deinit_occ_resp_buf(resp);
-	return ret;
-}
-
-#define RESP_DATA_LENGTH	3
-#define RESP_HEADER_OFFSET	5
-#define SENSOR_STR_OFFSET	37
-#define SENSOR_BLOCK_NUM_OFFSET	43
-#define SENSOR_BLOCK_OFFSET	45
-
-static inline uint16_t get_occdata_length(uint8_t *data)
-{
-	return be16_to_cpup((const __be16 *)&data[RESP_DATA_LENGTH]);
-}
-
-static int parse_occ_response(struct i2c_client *client,
-		uint8_t *data, struct occ_response *resp)
-{
-	int b;
-	int s;
-	int ret;
-	int dnum = SENSOR_BLOCK_OFFSET;
-	struct occ_sensor *f_sensor;
-	struct occ_sensor *t_sensor;
-	struct power_sensor *p_sensor;
-	struct caps_sensor *c_sensor;
-	uint8_t sensor_block_num;
-	uint8_t sensor_type[4];
-	uint8_t sensor_format;
-	uint8_t sensor_length;
-	uint8_t sensor_num;
-
-	/* check if the data is valid */
-	if (strncmp(&data[SENSOR_STR_OFFSET], "SENSOR", 6) != 0) {
-		dev_dbg(&client->dev,
-			"ERROR: no SENSOR String in response\n");
-		ret = -1;
-		goto err;
-	}
-
-	sensor_block_num = data[SENSOR_BLOCK_NUM_OFFSET];
-	if (sensor_block_num == 0) {
-		dev_dbg(&client->dev, "ERROR: SENSOR block num is 0\n");
-		ret = -1;
-		goto err;
-	}
-
-	/* if sensor block has changed, re-malloc */
-	if (sensor_block_num != resp->header.sensor_block_num) {
-		deinit_occ_resp_buf(resp);
-		resp->blocks = kcalloc(sensor_block_num,
-			sizeof(struct sensor_data_block), GFP_KERNEL);
-		if (!resp->blocks)
-			return -ENOMEM;
-	}
-
-	memcpy(&resp->header, &data[RESP_HEADER_OFFSET], sizeof(resp->header));
-	resp->header.error_log_addr_start =
-		be32_to_cpu(resp->header.error_log_addr_start);
-	resp->header.error_log_length =
-		be16_to_cpu(resp->header.error_log_length);
-
-	dev_dbg(&client->dev, "Reading %d sensor blocks\n",
-		resp->header.sensor_block_num);
-	for (b = 0; b < sensor_block_num; b++) {
-		/* 8-byte sensor block head */
-		strncpy(sensor_type, &data[dnum], 4);
-		sensor_format = data[dnum+5];
-		sensor_length = data[dnum+6];
-		sensor_num = data[dnum+7];
-		dnum = dnum + 8;
-
-		dev_dbg(&client->dev,
-			"sensor block[%d]: type: %s, sensor_num: %d\n",
-			b, sensor_type, sensor_num);
-
-		if (strncmp(sensor_type, "FREQ", 4) == 0) {
-			ret = occ_renew_sensor(resp, sensor_length,
-				sensor_num, freq, b);
-			if (ret)
-				continue;
-
-			resp->sensor_block_id[freq] = b;
-			for (s = 0; s < sensor_num; s++) {
-				f_sensor = &resp->blocks[b].sensor[s];
-				f_sensor->sensor_id =
-					be16_to_cpup((const __be16 *)
-							&data[dnum]);
-				f_sensor->value = be16_to_cpup((const __be16 *)
-							&data[dnum+2]);
-				dev_dbg(&client->dev,
-					"sensor[%d]-[%d]: id: %u, value: %u\n",
-					b, s, f_sensor->sensor_id,
-					f_sensor->value);
-				dnum = dnum + sensor_length;
-			}
-		} else if (strncmp(sensor_type, "TEMP", 4) == 0) {
-			ret = occ_renew_sensor(resp, sensor_length,
-				sensor_num, temp, b);
-			if (ret)
-				continue;
-
-			resp->sensor_block_id[temp] = b;
-			for (s = 0; s < sensor_num; s++) {
-				t_sensor = &resp->blocks[b].sensor[s];
-				t_sensor->sensor_id =
-					be16_to_cpup((const __be16 *)
-							&data[dnum]);
-				t_sensor->value = be16_to_cpup((const __be16 *)
-							&data[dnum+2]);
-				dev_dbg(&client->dev,
-					"sensor[%d]-[%d]: id: %u, value: %u\n",
-					b, s, t_sensor->sensor_id,
-					t_sensor->value);
-				dnum = dnum + sensor_length;
-			}
-		} else if (strncmp(sensor_type, "POWR", 4) == 0) {
-			ret = occ_renew_sensor(resp, sensor_length,
-				sensor_num, power, b);
-			if (ret)
-				continue;
-
-			resp->sensor_block_id[power] = b;
-			for (s = 0; s < sensor_num; s++) {
-				p_sensor = &resp->blocks[b].power[s];
-				p_sensor->sensor_id =
-					be16_to_cpup((const __be16 *)
-							&data[dnum]);
-				p_sensor->update_tag =
-					be32_to_cpup((const __be32 *)
-							&data[dnum+2]);
-				p_sensor->accumulator =
-					be32_to_cpup((const __be32 *)
-							&data[dnum+6]);
-				p_sensor->value = be16_to_cpup((const __be16 *)
-							&data[dnum+10]);
-
-				dev_dbg(&client->dev,
-					"sensor[%d]-[%d]: id: %u, value: %u\n",
-					b, s, p_sensor->sensor_id,
-					p_sensor->value);
-
-				dnum = dnum + sensor_length;
-			}
-		} else if (strncmp(sensor_type, "CAPS", 4) == 0) {
-			ret = occ_renew_sensor(resp, sensor_length,
-				sensor_num, caps, b);
-			if (ret)
-				continue;
-
-			resp->sensor_block_id[caps] = b;
-			for (s = 0; s < sensor_num; s++) {
-				c_sensor = &resp->blocks[b].caps[s];
-				c_sensor->curr_powercap =
-					be16_to_cpup((const __be16 *)
-							&data[dnum]);
-				c_sensor->curr_powerreading =
-					be16_to_cpup((const __be16 *)
-							&data[dnum+2]);
-				c_sensor->norm_powercap =
-					be16_to_cpup((const __be16 *)
-							&data[dnum+4]);
-				c_sensor->max_powercap =
-					be16_to_cpup((const __be16 *)
-							&data[dnum+6]);
-				c_sensor->min_powercap =
-					be16_to_cpup((const __be16 *)
-							&data[dnum+8]);
-				c_sensor->user_powerlimit =
-					be16_to_cpup((const __be16 *)
-							&data[dnum+10]);
-
-				dnum = dnum + sensor_length;
-				dev_dbg(&client->dev, "CAPS sensor #%d:\n", s);
-				dev_dbg(&client->dev, "curr_powercap is %x\n",
-					c_sensor->curr_powercap);
-				dev_dbg(&client->dev,
-					"curr_powerreading is %x\n",
-					c_sensor->curr_powerreading);
-				dev_dbg(&client->dev, "norm_powercap is %x\n",
-					c_sensor->norm_powercap);
-				dev_dbg(&client->dev, "max_powercap is %x\n",
-					c_sensor->max_powercap);
-				dev_dbg(&client->dev, "min_powercap is %x\n",
-					c_sensor->min_powercap);
-				dev_dbg(&client->dev, "user_powerlimit is %x\n",
-					c_sensor->user_powerlimit);
-			}
-
-		} else {
-			dev_dbg(&client->dev,
-				"ERROR: sensor type %s not supported\n",
-				resp->blocks[b].sensor_type);
-			ret = -1;
-			goto err;
-		}
-
-		strncpy(resp->blocks[b].sensor_type, sensor_type, 4);
-		resp->blocks[b].sensor_format = sensor_format;
-		resp->blocks[b].sensor_length = sensor_length;
-		resp->blocks[b].sensor_num = sensor_num;
-	}
-
-	return 0;
-err:
-	deinit_occ_resp_buf(resp);
-	return ret;
-}
-
-
-/* Refer to OCC interface document for OCC command format
- * https://github.com/open-power/docs/blob/master/occ/OCC_OpenPwr_FW_Interfaces.pdf
- */
-static uint8_t occ_send_cmd(struct i2c_client *client, uint8_t seq,
-		uint8_t type, uint16_t length, uint8_t *data, uint8_t *resp)
-{
-	uint32_t cmd1, cmd2;
-	uint16_t checksum;
-	int i;
-
-	length = cpu_to_le16(length);
-	cmd1 = (seq << 24) | (type << 16) | length;
-	memcpy(&cmd2, data, length);
-	cmd2 <<= ((4 - length) * 8);
-
-	/* checksum: sum of every bytes of cmd1, cmd2 */
-	checksum = 0;
-	for (i = 0; i < 4; i++)
-		checksum += (cmd1 >> (i * 8)) & 0xFF;
-	for (i = 0; i < 4; i++)
-		checksum += (cmd2 >> (i * 8)) & 0xFF;
-	cmd2 |= checksum << ((2 - length) * 8);
-
-	/* Init OCB */
-	occ_putscom(client, OCB_STATUS_CONTROL_OR,  0x08000000, 0x00000000);
-	occ_putscom(client, OCB_STATUS_CONTROL_AND, 0xFBFFFFFF, 0xFFFFFFFF);
-
-	/* Send command */
-	occ_putscom(client, OCB_ADDRESS, OCC_COMMAND_ADDR, 0x00000000);
-	occ_putscom(client, OCB_ADDRESS, OCC_COMMAND_ADDR, 0x00000000);
-	occ_putscom(client, OCB_DATA, cmd1, cmd2);
-
-	/* Trigger attention */
-	occ_putscom(client, ATTN_DATA, 0x01010000, 0x00000000);
-
-	/* Get response data */
-	occ_putscom(client, OCB_ADDRESS, OCC_RESPONSE_ADDR, 0x00000000);
-	occ_getscomb(client, OCB_DATA, resp, 0);
-
-	/* return status */
-	return resp[2];
-}
-
-static int occ_get_all(struct i2c_client *client, struct occ_response *occ_resp)
-{
-	uint8_t *occ_data;
-	uint16_t num_bytes;
-	int i;
-	int ret;
-	uint8_t poll_cmd_data;
-
-	poll_cmd_data = 0x10;
-
-	/*
-	 * TODO: fetch header, and then allocate the rest of the buffer based
-	 * on the header size. Assuming the OCC has a fixed sized header
-	 */
-	occ_data = devm_kzalloc(&client->dev, OCC_DATA_MAX, GFP_KERNEL);
-
-	ret = occ_send_cmd(client, 0, 0, 1, &poll_cmd_data, occ_data);
-	if (ret) {
-		dev_err(&client->dev, "ERROR: OCC Poll: 0x%x\n", ret);
-		ret = -EINVAL;
-		goto out;
-	}
-
-	num_bytes = get_occdata_length(occ_data);
-
-	dev_dbg(&client->dev, "OCC data length: %d\n", num_bytes);
-
-	if (num_bytes > OCC_DATA_MAX) {
-		dev_dbg(&client->dev, "ERROR: OCC data length must be < 4KB\n");
-		ret = -EINVAL;
-		goto out;
-	}
-
-	if (num_bytes <= 0) {
-		dev_dbg(&client->dev, "ERROR: OCC data length is zero\n");
-		ret = -EINVAL;
-		goto out;
-	}
-
-	/* read remaining data */
-	for (i = 8; i < num_bytes + 8; i = i + 8)
-		occ_getscomb(client, OCB_DATA, occ_data, i);
-
-	ret = parse_occ_response(client, occ_data, occ_resp);
-
-out:
-	devm_kfree(&client->dev, occ_data);
-	return ret;
-}
-
-
-static int occ_update_device(struct device *dev)
-{
-	struct occ_drv_data *data = dev_get_drvdata(dev);
-	struct i2c_client *client = data->client;
-	int ret = 0;
-
-	mutex_lock(&data->update_lock);
-
-	if (time_after(jiffies, data->last_updated + data->update_interval)
-	    || !data->valid) {
-		data->valid = 1;
-		ret = occ_get_all(client, &data->occ_resp);
-		if (ret)
-			data->valid = 0;
-		data->last_updated = jiffies;
-	}
-	mutex_unlock(&data->update_lock);
-
-	return ret;
-}
-
-
-static void *occ_get_sensor(struct device *hwmon_dev, enum sensor_t t)
-{
-	struct device *dev = hwmon_dev->parent;
-	struct occ_drv_data *data = dev_get_drvdata(dev);
-	int ret;
-
-	ret = occ_update_device(dev);
-	if (ret != 0) {
-		dev_dbg(dev, "ERROR: cannot get occ sensor data: %d\n", ret);
-		return NULL;
-	}
-
-	return occ_get_sensor_by_type(&data->occ_resp, t);
-}
-
-static int occ_get_sensor_value(struct device *hwmon_dev, enum sensor_t t,
-					int index)
-{
-	void *sensor;
-
-	if (t == caps)
-		return -1;
-
-	sensor = occ_get_sensor(hwmon_dev, t);
-
-	if (!sensor)
-		return -1;
-
-	if (t == power)
-		return ((struct power_sensor *)sensor)[index].value;
-
-	return ((struct occ_sensor *)sensor)[index].value;
-}
-
-static int occ_get_sensor_id(struct device *hwmon_dev, enum sensor_t t,
-					int index)
-{
-	void *sensor;
-
-	if (t == caps)
-		return -1;
-
-	sensor = occ_get_sensor(hwmon_dev, t);
-
-	if (!sensor)
-		return -1;
-
-	if (t == power)
-		return ((struct power_sensor *)sensor)[index].sensor_id;
-
-	return ((struct occ_sensor *)sensor)[index].sensor_id;
-}
-
-/* sysfs attributes for occ hwmon device */
-
-static ssize_t show_input(struct device *hwmon_dev,
-				struct device_attribute *da, char *buf)
-{
-	struct sensor_attr_data *sdata = container_of(da,
-					struct sensor_attr_data, dev_attr);
-	int val;
-
-	val = occ_get_sensor_value(hwmon_dev, sdata->type,
-					sdata->hwmon_index - 1);
-	if (sdata->type == temp)
-		/* in millidegree Celsius */
-		val *= 1000;
-
-	return snprintf(buf, PAGE_SIZE - 1, "%d\n", val);
-}
-
-static ssize_t show_label(struct device *hwmon_dev,
-			struct device_attribute *da, char *buf)
-{
-	struct sensor_attr_data *sdata = container_of(da,
-					struct sensor_attr_data, dev_attr);
-	int val;
-
-	val = occ_get_sensor_id(hwmon_dev, sdata->type,
-					sdata->hwmon_index - 1);
-
-	return snprintf(buf, PAGE_SIZE - 1, "%d\n", val);
-}
-
-static ssize_t show_caps(struct device *hwmon_dev,
-		struct device_attribute *da, char *buf)
-{
-	struct sensor_attr_data *sdata = container_of(da,
-					struct sensor_attr_data, dev_attr);
-	int nr = sdata->attr_id;
-	int n = sdata->hwmon_index - 1;
-	struct caps_sensor *sensor;
-	int val;
-
-	sensor = occ_get_sensor(hwmon_dev, caps);
-	if (!sensor) {
-		val = -1;
-		return snprintf(buf, PAGE_SIZE - 1, "%d\n", val);
-	}
-
-	switch (nr) {
-	case 0:
-		val = sensor[n].curr_powercap;
-		break;
-	case 1:
-		val = sensor[n].curr_powerreading;
-		break;
-	case 2:
-		val = sensor[n].norm_powercap;
-		break;
-	case 3:
-		val = sensor[n].max_powercap;
-		break;
-	case 4:
-		val = sensor[n].min_powercap;
-		break;
-	case 5:
-		val = sensor[n].user_powerlimit;
-		break;
-	default:
-		val = -1;
-	}
-
-	return snprintf(buf, PAGE_SIZE - 1, "%d\n", val);
-}
-
-static ssize_t show_update_interval(struct device *hwmon_dev,
-				struct device_attribute *attr, char *buf)
-{
-	struct device *dev = hwmon_dev->parent;
-	struct occ_drv_data *data = dev_get_drvdata(dev);
-
-	return snprintf(buf, PAGE_SIZE - 1, "%u\n",
-		jiffies_to_msecs(data->update_interval));
-}
-
-static ssize_t set_update_interval(struct device *hwmon_dev,
-				struct device_attribute *attr,
-				const char *buf, size_t count)
-{
-	struct device *dev = hwmon_dev->parent;
-	struct occ_drv_data *data = dev_get_drvdata(dev);
-	unsigned long val;
-	int err;
-
-	err = kstrtoul(buf, 10, &val);
-	if (err)
-		return err;
-
-	data->update_interval = msecs_to_jiffies(val);
-	return count;
-}
-static DEVICE_ATTR(update_interval, S_IWUSR | S_IRUGO,
-		show_update_interval, set_update_interval);
-
-static ssize_t show_name(struct device *hwmon_dev,
-				struct device_attribute *attr, char *buf)
-{
-	return snprintf(buf, PAGE_SIZE - 1, "%s\n", OCC_I2C_NAME);
-}
-static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
-
-static ssize_t show_user_powercap(struct device *hwmon_dev,
-				struct device_attribute *attr, char *buf)
-{
-	struct device *dev = hwmon_dev->parent;
-	struct occ_drv_data *data = dev_get_drvdata(dev);
-
-	return snprintf(buf, PAGE_SIZE - 1, "%u\n", data->user_powercap);
-}
-
-
-static ssize_t set_user_powercap(struct device *hwmon_dev,
-				struct device_attribute *attr,
-				const char *buf, size_t count)
-{
-	struct device *dev = hwmon_dev->parent;
-	struct occ_drv_data *data = dev_get_drvdata(dev);
-	struct i2c_client *client = data->client;
-	uint16_t val;
-	uint8_t resp[8];
-	int err;
-
-	err = kstrtou16(buf, 10, &val);
-	if (err)
-		return err;
-
-	dev_dbg(dev, "set user powercap to: %u\n", val);
-	val = cpu_to_le16(val);
-	err = occ_send_cmd(client, 0, 0x22, 2, (uint8_t *)&val, resp);
-	if (err != 0) {
-		dev_dbg(dev,
-			"ERROR: Set User Powercap: wrong return status: %x\n",
-			err);
-		if (err == 0x13)
-			dev_info(dev,
-				"ERROR: set invalid powercap value: %x\n", val);
-		return -EINVAL;
-	}
-	data->user_powercap = val;
-	return count;
-}
-static DEVICE_ATTR(user_powercap, S_IWUSR | S_IRUGO,
-		show_user_powercap, set_user_powercap);
-
-static void deinit_sensor_groups(struct device *hwmon_dev,
-					struct sensor_group *sensor_groups)
-{
-	int cnt;
-
-	for (cnt = 0; cnt < MAX_OCC_SENSOR_TYPE; cnt++) {
-		if (sensor_groups[cnt].group.attrs)
-			devm_kfree(hwmon_dev, sensor_groups[cnt].group.attrs);
-		if (sensor_groups[cnt].sattr)
-			devm_kfree(hwmon_dev, sensor_groups[cnt].sattr);
-		sensor_groups[cnt].group.attrs = NULL;
-		sensor_groups[cnt].sattr = NULL;
-	}
-}
-
-static void occ_remove_hwmon_attrs(struct device *hwmon_dev)
-{
-	struct occ_drv_data *data = dev_get_drvdata(hwmon_dev->parent);
-	struct sensor_group *sensor_groups = data->sensor_groups;
-	int i;
-
-	if (!hwmon_dev)
-		return;
-
-	device_remove_file(hwmon_dev, &dev_attr_update_interval);
-	device_remove_file(hwmon_dev, &dev_attr_name);
-	device_remove_file(hwmon_dev, &dev_attr_user_powercap);
-
-	for (i = 0; i < MAX_OCC_SENSOR_TYPE; i++)
-		sysfs_remove_group(&hwmon_dev->kobj, &sensor_groups[i].group);
-
-	deinit_sensor_groups(hwmon_dev, sensor_groups);
-}
-
-static void sensor_attr_init(struct sensor_attr_data *sdata,
-				char *sensor_group_name,
-				char *attr_name,
-				ssize_t (*show)(struct device *dev,
-						struct device_attribute *attr,
-						char *buf))
-{
-	sysfs_attr_init(&sdata->dev_attr.attr);
-
-	snprintf(sdata->name, MAX_SENSOR_ATTR_LEN, "%s%d_%s",
-		sensor_group_name, sdata->hwmon_index, attr_name);
-	sdata->dev_attr.attr.name = sdata->name;
-	sdata->dev_attr.attr.mode = S_IRUGO;
-	sdata->dev_attr.show = show;
-}
-
-/* create hwmon sensor sysfs attributes */
-static int create_sensor_group(struct device *hwmon_dev, enum sensor_t type,
-				int sensor_num)
-{
-	struct occ_drv_data *data = dev_get_drvdata(hwmon_dev->parent);
-	struct sensor_group *sensor_groups = data->sensor_groups;
-	struct sensor_attr_data *sdata;
-	int ret;
-	int cnt;
-
-	/* each sensor has 'label' and 'input' attributes */
-	sensor_groups[type].group.attrs = devm_kzalloc(hwmon_dev,
-						sizeof(struct attribute *) *
-						sensor_num * 2 + 1, GFP_KERNEL);
-	if (!sensor_groups[type].group.attrs) {
-		ret = -ENOMEM;
-		goto err;
-	}
-
-	sensor_groups[type].sattr = devm_kzalloc(hwmon_dev,
-					sizeof(struct sensor_attr_data) *
-					sensor_num * 2, GFP_KERNEL);
-	if (!sensor_groups[type].sattr) {
-		ret = -ENOMEM;
-		goto err;
-	}
-
-	for (cnt = 0; cnt < sensor_num; cnt++) {
-		sdata = &sensor_groups[type].sattr[cnt];
-		/* hwomon attributes index starts from 1 */
-		sdata->hwmon_index = cnt + 1;
-		sdata->type = type;
-		sensor_attr_init(sdata, sensor_groups[type].name, "input",
-					show_input);
-		sensor_groups[type].group.attrs[cnt] = &sdata->dev_attr.attr;
-
-		sdata = &sensor_groups[type].sattr[cnt + sensor_num];
-		sdata->hwmon_index = cnt + 1;
-		sdata->type = type;
-		sensor_attr_init(sdata, sensor_groups[type].name, "label",
-					show_label);
-		sensor_groups[type].group.attrs[cnt + sensor_num] =
-			&sdata->dev_attr.attr;
-	}
-
-	ret = sysfs_create_group(&hwmon_dev->kobj, &sensor_groups[type].group);
-	if (ret)
-		goto err;
-
-	return ret;
-err:
-	deinit_sensor_groups(hwmon_dev, sensor_groups);
-	return ret;
-}
-
-static void caps_sensor_attr_init(struct sensor_attr_data *sdata,
-					char *attr_name, uint32_t hwmon_index,
-					uint32_t attr_id)
-{
-	sdata->type = caps;
-	sdata->hwmon_index = hwmon_index;
-	sdata->attr_id = attr_id;
-
-	/* FIXME, to be compatible with user space app, we do not
-	 * generate caps1_* attributes.
-	 */
-	if (sdata->hwmon_index == 1)
-		snprintf(sdata->name, MAX_SENSOR_ATTR_LEN, "%s_%s",
-			"caps", attr_name);
-	else
-		snprintf(sdata->name, MAX_SENSOR_ATTR_LEN, "%s%d_%s",
-			"caps", sdata->hwmon_index, attr_name);
-
-	sysfs_attr_init(&sdata->dev_attr.attr);
-	sdata->dev_attr.attr.name = sdata->name;
-	sdata->dev_attr.attr.mode = S_IRUGO;
-	sdata->dev_attr.show = show_caps;
-}
-
-static char *caps_sensor_name[] = {
-	"curr_powercap",
-	"curr_powerreading",
-	"norm_powercap",
-	"max_powercap",
-	"min_powercap",
-	"user_powerlimit",
-};
-
-static int create_caps_sensor_group(struct device *hwmon_dev, int sensor_num)
-{
-	struct occ_drv_data *data = dev_get_drvdata(hwmon_dev->parent);
-	struct sensor_group *sensor_groups = data->sensor_groups;
-	int field_num = ARRAY_SIZE(caps_sensor_name);
-	struct sensor_attr_data *sdata;
-	int ret;
-	int cnt;
-	int i;
-
-	sensor_groups[caps].group.attrs = devm_kzalloc(hwmon_dev,
-						sizeof(struct attribute *) *
-						sensor_num * field_num + 1,
-						GFP_KERNEL);
-	if (!sensor_groups[caps].group.attrs) {
-		ret = -ENOMEM;
-		goto err;
-	}
-
-	sensor_groups[caps].sattr = devm_kzalloc(hwmon_dev,
-					sizeof(struct sensor_attr_data) *
-					sensor_num * field_num,
-					GFP_KERNEL);
-	if (!sensor_groups[caps].sattr) {
-		ret = -ENOMEM;
-		goto err;
-	}
-
-	for (cnt = 0; cnt < sensor_num; cnt++) {
-		for (i = 0; i < field_num; i++) {
-			sdata = &sensor_groups[caps].sattr[cnt * field_num + i];
-			caps_sensor_attr_init(sdata, caps_sensor_name[i],
-						cnt + 1, i);
-			sensor_groups[caps].group.attrs[cnt * field_num + i] =
-						&sdata->dev_attr.attr;
-		}
-	}
-
-	ret = sysfs_create_group(&hwmon_dev->kobj, &sensor_groups[caps].group);
-	if (ret)
-		goto err;
-
-	return ret;
-err:
-	deinit_sensor_groups(hwmon_dev, sensor_groups);
-	return ret;
-}
-
-static int occ_create_hwmon_attrs(struct device *dev)
-{
-	struct occ_drv_data *drv_data = dev_get_drvdata(dev);
-	struct device *hwmon_dev = drv_data->hwmon_dev;
-	struct sensor_group *sensor_groups = drv_data->sensor_groups;
-	int i;
-	int sensor_num;
-	int ret;
-	struct occ_response *rsp;
-	enum sensor_t t;
-
-	rsp = &drv_data->occ_resp;
-
-	for (i = 0; i < ARRAY_SIZE(rsp->sensor_block_id); i++)
-		rsp->sensor_block_id[i] = -1;
-
-	/* read sensor data from occ. */
-	ret = occ_update_device(dev);
-	if (ret != 0) {
-		dev_dbg(dev, "ERROR: cannot get occ sensor data: %d\n", ret);
-		return ret;
-	}
-	if (!rsp->blocks)
-		return -1;
-
-	ret = device_create_file(hwmon_dev, &dev_attr_name);
-	if (ret)
-		goto error;
-
-	ret = device_create_file(hwmon_dev, &dev_attr_update_interval);
-	if (ret)
-		goto error;
-
-	if (rsp->sensor_block_id[caps] >= 0) {
-		/* user powercap: only for master OCC */
-		ret = device_create_file(hwmon_dev, &dev_attr_user_powercap);
-		if (ret)
-			goto error;
-	}
-
-	sensor_groups[freq].name = "freq";
-	sensor_groups[temp].name = "temp";
-	sensor_groups[power].name = "power";
-	sensor_groups[caps].name =  "caps";
-
-	for (t = 0; t < MAX_OCC_SENSOR_TYPE; t++) {
-		if (rsp->sensor_block_id[t] < 0)
-			continue;
-
-		sensor_num =
-			rsp->blocks[rsp->sensor_block_id[t]].sensor_num;
-		if (t == caps)
-			ret = create_caps_sensor_group(hwmon_dev, sensor_num);
-		else
-			ret = create_sensor_group(hwmon_dev, t, sensor_num);
-		if (ret)
-			goto error;
-	}
-
-	return 0;
-error:
-	dev_err(dev, "ERROR: cannot create hwmon attributes\n");
-	occ_remove_hwmon_attrs(drv_data->hwmon_dev);
-	return ret;
-}
-
-static ssize_t show_occ_online(struct device *dev,
-				struct device_attribute *attr, char *buf)
-{
-	struct occ_drv_data *data = dev_get_drvdata(dev);
-
-	return snprintf(buf, PAGE_SIZE - 1, "%lu\n", data->occ_online);
-}
-
-static ssize_t set_occ_online(struct device *dev,
-				struct device_attribute *attr,
-				const char *buf, size_t count)
-{
-	struct occ_drv_data *data = dev_get_drvdata(dev);
-	unsigned long val;
-	int err;
-
-	err = kstrtoul(buf, 10, &val);
-	if (err)
-		return err;
-
-	if (val == 1) {
-		if (data->occ_online == 1)
-			return count;
-
-		/* populate hwmon sysfs attr using sensor data */
-		dev_dbg(dev, "occ register hwmon @0x%x\n", data->client->addr);
-
-		data->hwmon_dev = hwmon_device_register(dev);
-		if (IS_ERR(data->hwmon_dev))
-			return PTR_ERR(data->hwmon_dev);
-
-		err = occ_create_hwmon_attrs(dev);
-		if (err) {
-			hwmon_device_unregister(data->hwmon_dev);
-			return err;
-		}
-		data->hwmon_dev->parent = dev;
-	} else if (val == 0) {
-		if (data->occ_online == 0)
-			return count;
-
-		occ_remove_hwmon_attrs(data->hwmon_dev);
-		hwmon_device_unregister(data->hwmon_dev);
-		data->hwmon_dev = NULL;
-	} else
-		return -EINVAL;
-
-	data->occ_online = val;
-	return count;
-}
-
-static DEVICE_ATTR(online, S_IWUSR | S_IRUGO,
-		show_occ_online, set_occ_online);
-
-static int occ_create_i2c_sysfs_attr(struct device *dev)
-{
-	/* create an i2c sysfs attribute, to indicate whether OCC is active */
-	return device_create_file(dev, &dev_attr_online);
-}
-
-
-/* device probe and removal */
-
-enum occ_type {
-	occ_id,
-};
-
-static int occ_probe(struct i2c_client *client, const struct i2c_device_id *id)
-{
-	struct device *dev = &client->dev;
-	struct occ_drv_data *data;
-
-	data = devm_kzalloc(dev, sizeof(struct occ_drv_data), GFP_KERNEL);
-	if (!data)
-		return -ENOMEM;
-
-	data->client = client;
-	i2c_set_clientdata(client, data);
-	mutex_init(&data->update_lock);
-	data->update_interval = HZ;
-
-	occ_create_i2c_sysfs_attr(dev);
-
-	dev_info(dev, "occ i2c driver ready: i2c addr@0x%x\n", client->addr);
-
-	return 0;
-}
-
-static int occ_remove(struct i2c_client *client)
-{
-	struct occ_drv_data *data = i2c_get_clientdata(client);
-
-	/* free allocated sensor memory */
-	deinit_occ_resp_buf(&data->occ_resp);
-
-	device_remove_file(&client->dev, &dev_attr_online);
-
-	if (!data->hwmon_dev)
-		return 0;
-
-	occ_remove_hwmon_attrs(data->hwmon_dev);
-	hwmon_device_unregister(data->hwmon_dev);
-	return 0;
-}
-
-/* used by old-style board info. */
-static const struct i2c_device_id occ_ids[] = {
-	{ OCC_I2C_NAME, occ_id, },
-	{ /* LIST END */ }
-};
-MODULE_DEVICE_TABLE(i2c, occ_ids);
-
-/* use by device table */
-static const struct of_device_id i2c_occ_of_match[] = {
-	{.compatible = "ibm,occ-i2c"},
-	{},
-};
-MODULE_DEVICE_TABLE(of, i2c_occ_of_match);
-
-/* i2c-core uses i2c-detect() to detect device in bellow address list.
- *  If exists, address will be assigned to client.
- * It is also possible to read address from device table.
- */
-static const unsigned short normal_i2c[] = {0x50, 0x51, I2C_CLIENT_END };
-
-static struct i2c_driver occ_driver = {
-	.class		= I2C_CLASS_HWMON,
-	.driver = {
-		.name	= OCC_I2C_NAME,
-		.pm	= NULL,
-		.of_match_table = i2c_occ_of_match,
-	},
-	.probe		= occ_probe,
-	.remove		= occ_remove,
-	.id_table       = occ_ids,
-	.address_list	= normal_i2c,
-};
-
-module_i2c_driver(occ_driver);
-
-MODULE_AUTHOR("Li Yi <shliyi@cn.ibm.com>");
-MODULE_DESCRIPTION("BMC OCC hwmon driver");
-MODULE_LICENSE("GPL");
-- 
1.9.1