text: /*
   * Hardware monitoring driver for UCD90xxx Sequencer and System Health
   * Controller series
   *
   * Copyright (C) 2011 Ericsson AB.
   *
   * 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.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program; if not, write to the Free Software
   * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
   */
  
  #include <linux/kernel.h>
  #include <linux/module.h>
  #include <linux/of_device.h>
  #include <linux/init.h>
  #include <linux/err.h>
  #include <linux/slab.h>
  #include <linux/i2c.h>
  #include <linux/pmbus.h>
  #include "pmbus.h"
  
  enum chips { ucd9000, ucd90120, ucd90124, ucd90160, ucd9090, ucd90910 };
  
  #define UCD9000_MONITOR_CONFIG		0xd5
  #define UCD9000_NUM_PAGES		0xd6
  #define UCD9000_FAN_CONFIG_INDEX	0xe7
  #define UCD9000_FAN_CONFIG		0xe8
  #define UCD9000_DEVICE_ID		0xfd
  
  #define UCD9000_MON_TYPE(x)	(((x) >> 5) & 0x07)
  #define UCD9000_MON_PAGE(x)	((x) & 0x0f)
  
  #define UCD9000_MON_VOLTAGE	1
  #define UCD9000_MON_TEMPERATURE	2
  #define UCD9000_MON_CURRENT	3
  #define UCD9000_MON_VOLTAGE_HW	4
  
  #define UCD9000_NUM_FAN		4
  
  struct ucd9000_data {
  	u8 fan_data[UCD9000_NUM_FAN][I2C_SMBUS_BLOCK_MAX];
  	struct pmbus_driver_info info;
  };
  #define to_ucd9000_data(_info) container_of(_info, struct ucd9000_data, info)
  
  static int ucd9000_get_fan_config(struct i2c_client *client, int fan)
  {
  	int fan_config = 0;
  	struct ucd9000_data *data
  	  = to_ucd9000_data(pmbus_get_driver_info(client));
  
  	if (data->fan_data[fan][3] & 1)
  		fan_config |= PB_FAN_2_INSTALLED;   /* Use lower bit position */
  
  	/* Pulses/revolution */
  	fan_config |= (data->fan_data[fan][3] & 0x06) >> 1;
  
  	return fan_config;
  }
  
  static int ucd9000_read_byte_data(struct i2c_client *client, int page, int reg)
  {
  	int ret = 0;
  	int fan_config;
  
  	switch (reg) {
  	case PMBUS_FAN_CONFIG_12:
  		if (page > 0)
  			return -ENXIO;
  
  		ret = ucd9000_get_fan_config(client, 0);
  		if (ret < 0)
  			return ret;
  		fan_config = ret << 4;
  		ret = ucd9000_get_fan_config(client, 1);
  		if (ret < 0)
  			return ret;
  		fan_config |= ret;
  		ret = fan_config;
  		break;
  	case PMBUS_FAN_CONFIG_34:
  		if (page > 0)
  			return -ENXIO;
  
  		ret = ucd9000_get_fan_config(client, 2);
  		if (ret < 0)
  			return ret;
  		fan_config = ret << 4;
  		ret = ucd9000_get_fan_config(client, 3);
  		if (ret < 0)
  			return ret;
  		fan_config |= ret;
  		ret = fan_config;
  		break;
  	default:
  		ret = -ENODATA;
  		break;
  	}
  	return ret;
  }
  
  static const struct i2c_device_id ucd9000_id[] = {
  	{"ucd9000", ucd9000},
  	{"ucd90120", ucd90120},
  	{"ucd90124", ucd90124},
  	{"ucd90160", ucd90160},
  	{"ucd9090", ucd9090},
  	{"ucd90910", ucd90910},
  	{}
  };
  MODULE_DEVICE_TABLE(i2c, ucd9000_id);
  
  static const struct of_device_id ucd9000_of_match[] = {
  	{
  		.compatible = "ti,ucd9000",
  		.data = (void *)ucd9000
  	},
  	{
  		.compatible = "ti,ucd90120",
  		.data = (void *)ucd90120
  	},
  	{
  		.compatible = "ti,ucd90124",
  		.data = (void *)ucd90124
  	},
  	{
  		.compatible = "ti,ucd90160",
  		.data = (void *)ucd90160
  	},
  	{
  		.compatible = "ti,ucd9090",
  		.data = (void *)ucd9090
  	},
  	{
  		.compatible = "ti,ucd90910",
  		.data = (void *)ucd90910
  	},
  	{ },
  };
  MODULE_DEVICE_TABLE(of, ucd9000_of_match);
  
  static int ucd9000_probe(struct i2c_client *client,
  			 const struct i2c_device_id *id)
  {
  	u8 block_buffer[I2C_SMBUS_BLOCK_MAX + 1];
  	struct ucd9000_data *data;
  	struct pmbus_driver_info *info;
  	const struct i2c_device_id *mid;
  	enum chips chip;
  	int i, ret;
  
  	if (!i2c_check_functionality(client->adapter,
  				     I2C_FUNC_SMBUS_BYTE_DATA |
  				     I2C_FUNC_SMBUS_BLOCK_DATA))
  		return -ENODEV;
  
  	ret = i2c_smbus_read_block_data(client, UCD9000_DEVICE_ID,
  					block_buffer);
  	if (ret < 0) {
  		dev_err(&client->dev, "Failed to read device ID\n");
  		return ret;
  	}
  	block_buffer[ret] = '\0';
  	dev_info(&client->dev, "Device ID %s\n", block_buffer);
  
  	for (mid = ucd9000_id; mid->name[0]; mid++) {
  		if (!strncasecmp(mid->name, block_buffer, strlen(mid->name)))
  			break;
  	}
  	if (!mid->name[0]) {
  		dev_err(&client->dev, "Unsupported device\n");
  		return -ENODEV;
  	}
  
  	if (client->dev.of_node)
  		chip = (enum chips)of_device_get_match_data(&client->dev);
  	else
  		chip = id->driver_data;
  
  	if (chip != ucd9000 && chip != mid->driver_data)
  		dev_notice(&client->dev,
  			   "Device mismatch: Configured %s, detected %s\n",
  			   id->name, mid->name);
  
  	data = devm_kzalloc(&client->dev, sizeof(struct ucd9000_data),
  			    GFP_KERNEL);
  	if (!data)
  		return -ENOMEM;
  	info = &data->info;
  
  	ret = i2c_smbus_read_byte_data(client, UCD9000_NUM_PAGES);
  	if (ret < 0) {
  		dev_err(&client->dev,
  			"Failed to read number of active pages\n");
  		return ret;
  	}
  	info->pages = ret;
  	if (!info->pages) {
  		dev_err(&client->dev, "No pages configured\n");
  		return -ENODEV;
  	}
  
  	/* The internal temperature sensor is always active */
  	info->func[0] = PMBUS_HAVE_TEMP;
  
  	/* Everything else is configurable */
  	ret = i2c_smbus_read_block_data(client, UCD9000_MONITOR_CONFIG,
  					block_buffer);
  	if (ret <= 0) {
  		dev_err(&client->dev, "Failed to read configuration data\n");
  		return -ENODEV;
  	}
  	for (i = 0; i < ret; i++) {
  		int page = UCD9000_MON_PAGE(block_buffer[i]);
  
  		if (page >= info->pages)
  			continue;
  
  		switch (UCD9000_MON_TYPE(block_buffer[i])) {
  		case UCD9000_MON_VOLTAGE:
  		case UCD9000_MON_VOLTAGE_HW:
  			info->func[page] |= PMBUS_HAVE_VOUT
  			  | PMBUS_HAVE_STATUS_VOUT;
  			break;
  		case UCD9000_MON_TEMPERATURE:
  			info->func[page] |= PMBUS_HAVE_TEMP2
  			  | PMBUS_HAVE_STATUS_TEMP;
  			break;
  		case UCD9000_MON_CURRENT:
  			info->func[page] |= PMBUS_HAVE_IOUT
  			  | PMBUS_HAVE_STATUS_IOUT;
  			break;
  		default:
  			break;
  		}
  	}
  
  	/* Fan configuration */
  	if (mid->driver_data == ucd90124) {
  		for (i = 0; i < UCD9000_NUM_FAN; i++) {
  			i2c_smbus_write_byte_data(client,
  						  UCD9000_FAN_CONFIG_INDEX, i);
  			ret = i2c_smbus_read_block_data(client,
  							UCD9000_FAN_CONFIG,
  							data->fan_data[i]);
  			if (ret < 0)
  				return ret;
  		}
  		i2c_smbus_write_byte_data(client, UCD9000_FAN_CONFIG_INDEX, 0);
  
  		info->read_byte_data = ucd9000_read_byte_data;
  		info->func[0] |= PMBUS_HAVE_FAN12 | PMBUS_HAVE_STATUS_FAN12
  		  | PMBUS_HAVE_FAN34 | PMBUS_HAVE_STATUS_FAN34;
  	}
  
  	return pmbus_do_probe(client, mid, info);
  }
  
  /* This is the driver that will be inserted */
  static struct i2c_driver ucd9000_driver = {
  	.driver = {
  		.name = "ucd9000",
  		.of_match_table = of_match_ptr(ucd9000_of_match),
  	},
  	.probe = ucd9000_probe,
  	.remove = pmbus_do_remove,
  	.id_table = ucd9000_id,
  };
  
  module_i2c_driver(ucd9000_driver);
  
  MODULE_AUTHOR("Guenter Roeck");
  MODULE_DESCRIPTION("PMBus driver for TI UCD90xxx");
  MODULE_LICENSE("GPL");
  