/drivers/hwmon/max8688.c

  1/*
  2 * Hardware monitoring driver for Maxim MAX8688
  3 *
  4 * Copyright (c) 2011 Ericsson AB.
  5 *
  6 * This program is free software; you can redistribute it and/or modify
  7 * it under the terms of the GNU General Public License as published by
  8 * the Free Software Foundation; either version 2 of the License, or
  9 * (at your option) any later version.
 10 *
 11 * This program is distributed in the hope that it will be useful,
 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 14 * GNU General Public License for more details.
 15 *
 16 * You should have received a copy of the GNU General Public License
 17 * along with this program; if not, write to the Free Software
 18 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 19 */
 20
 21#include <linux/kernel.h>
 22#include <linux/module.h>
 23#include <linux/init.h>
 24#include <linux/err.h>
 25#include <linux/i2c.h>
 26#include "pmbus.h"
 27
 28#define MAX8688_MFG_STATUS		0xd8
 29
 30#define MAX8688_STATUS_OC_FAULT		(1 << 4)
 31#define MAX8688_STATUS_OV_FAULT		(1 << 5)
 32#define MAX8688_STATUS_OV_WARNING	(1 << 8)
 33#define MAX8688_STATUS_UV_FAULT		(1 << 9)
 34#define MAX8688_STATUS_UV_WARNING	(1 << 10)
 35#define MAX8688_STATUS_UC_FAULT		(1 << 11)
 36#define MAX8688_STATUS_OC_WARNING	(1 << 12)
 37#define MAX8688_STATUS_OT_FAULT		(1 << 13)
 38#define MAX8688_STATUS_OT_WARNING	(1 << 14)
 39
 40static int max8688_read_byte_data(struct i2c_client *client, int page, int reg)
 41{
 42	int ret = 0;
 43	int mfg_status;
 44
 45	if (page)
 46		return -EINVAL;
 47
 48	switch (reg) {
 49	case PMBUS_STATUS_VOUT:
 50		mfg_status = pmbus_read_word_data(client, 0,
 51						  MAX8688_MFG_STATUS);
 52		if (mfg_status < 0)
 53			return mfg_status;
 54		if (mfg_status & MAX8688_STATUS_UV_WARNING)
 55			ret |= PB_VOLTAGE_UV_WARNING;
 56		if (mfg_status & MAX8688_STATUS_UV_FAULT)
 57			ret |= PB_VOLTAGE_UV_FAULT;
 58		if (mfg_status & MAX8688_STATUS_OV_WARNING)
 59			ret |= PB_VOLTAGE_OV_WARNING;
 60		if (mfg_status & MAX8688_STATUS_OV_FAULT)
 61			ret |= PB_VOLTAGE_OV_FAULT;
 62		break;
 63	case PMBUS_STATUS_IOUT:
 64		mfg_status = pmbus_read_word_data(client, 0,
 65						  MAX8688_MFG_STATUS);
 66		if (mfg_status < 0)
 67			return mfg_status;
 68		if (mfg_status & MAX8688_STATUS_UC_FAULT)
 69			ret |= PB_IOUT_UC_FAULT;
 70		if (mfg_status & MAX8688_STATUS_OC_WARNING)
 71			ret |= PB_IOUT_OC_WARNING;
 72		if (mfg_status & MAX8688_STATUS_OC_FAULT)
 73			ret |= PB_IOUT_OC_FAULT;
 74		break;
 75	case PMBUS_STATUS_TEMPERATURE:
 76		mfg_status = pmbus_read_word_data(client, 0,
 77						  MAX8688_MFG_STATUS);
 78		if (mfg_status < 0)
 79			return mfg_status;
 80		if (mfg_status & MAX8688_STATUS_OT_WARNING)
 81			ret |= PB_TEMP_OT_WARNING;
 82		if (mfg_status & MAX8688_STATUS_OT_FAULT)
 83			ret |= PB_TEMP_OT_FAULT;
 84		break;
 85	default:
 86		ret = -ENODATA;
 87		break;
 88	}
 89	return ret;
 90}
 91
 92static struct pmbus_driver_info max8688_info = {
 93	.pages = 1,
 94	.direct[PSC_VOLTAGE_IN] = true,
 95	.direct[PSC_VOLTAGE_OUT] = true,
 96	.direct[PSC_TEMPERATURE] = true,
 97	.direct[PSC_CURRENT_OUT] = true,
 98	.m[PSC_VOLTAGE_IN] = 19995,
 99	.b[PSC_VOLTAGE_IN] = 0,
100	.R[PSC_VOLTAGE_IN] = -1,
101	.m[PSC_VOLTAGE_OUT] = 19995,
102	.b[PSC_VOLTAGE_OUT] = 0,
103	.R[PSC_VOLTAGE_OUT] = -1,
104	.m[PSC_CURRENT_OUT] = 23109,
105	.b[PSC_CURRENT_OUT] = 0,
106	.R[PSC_CURRENT_OUT] = -2,
107	.m[PSC_TEMPERATURE] = -7612,
108	.b[PSC_TEMPERATURE] = 335,
109	.R[PSC_TEMPERATURE] = -3,
110	.func[0] = PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT | PMBUS_HAVE_TEMP
111		| PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT
112		| PMBUS_HAVE_STATUS_TEMP,
113	.read_byte_data = max8688_read_byte_data,
114};
115
116static int max8688_probe(struct i2c_client *client,
117			 const struct i2c_device_id *id)
118{
119	return pmbus_do_probe(client, id, &max8688_info);
120}
121
122static int max8688_remove(struct i2c_client *client)
123{
124	return pmbus_do_remove(client);
125}
126
127static const struct i2c_device_id max8688_id[] = {
128	{"max8688", 0},
129	{ }
130};
131
132MODULE_DEVICE_TABLE(i2c, max8688_id);
133
134/* This is the driver that will be inserted */
135static struct i2c_driver max8688_driver = {
136	.driver = {
137		   .name = "max8688",
138		   },
139	.probe = max8688_probe,
140	.remove = max8688_remove,
141	.id_table = max8688_id,
142};
143
144static int __init max8688_init(void)
145{
146	return i2c_add_driver(&max8688_driver);
147}
148
149static void __exit max8688_exit(void)
150{
151	i2c_del_driver(&max8688_driver);
152}
153
154MODULE_AUTHOR("Guenter Roeck");
155MODULE_DESCRIPTION("PMBus driver for Maxim MAX8688");
156MODULE_LICENSE("GPL");
157module_init(max8688_init);
158module_exit(max8688_exit);