aboutsummaryrefslogtreecommitdiff
path: root/drivers/hwmon/pmbus/pmbus.c
blob: da5fe361a94051c9230d3ff8a7f2feaa3d1bdd17 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
/*
 * Hardware monitoring driver for PMBus devices
 *
 * Copyright (c) 2010, 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/init.h>
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/mutex.h>
#include <linux/i2c.h>
#include "pmbus.h"

/*
 * Find sensor groups and status registers on each page.
 */
static void pmbus_find_sensor_groups(struct i2c_client *client,
				     struct pmbus_driver_info *info)
{
	int page;

	/* Sensors detected on page 0 only */
	if (pmbus_check_word_register(client, 0, PMBUS_READ_VIN))
		info->func[0] |= PMBUS_HAVE_VIN;
	if (pmbus_check_word_register(client, 0, PMBUS_READ_VCAP))
		info->func[0] |= PMBUS_HAVE_VCAP;
	if (pmbus_check_word_register(client, 0, PMBUS_READ_IIN))
		info->func[0] |= PMBUS_HAVE_IIN;
	if (pmbus_check_word_register(client, 0, PMBUS_READ_PIN))
		info->func[0] |= PMBUS_HAVE_PIN;
	if (info->func[0]
	    && pmbus_check_byte_register(client, 0, PMBUS_STATUS_INPUT))
		info->func[0] |= PMBUS_HAVE_STATUS_INPUT;
	if (pmbus_check_byte_register(client, 0, PMBUS_FAN_CONFIG_12) &&
	    pmbus_check_word_register(client, 0, PMBUS_READ_FAN_SPEED_1)) {
		info->func[0] |= PMBUS_HAVE_FAN12;
		if (pmbus_check_byte_register(client, 0, PMBUS_STATUS_FAN_12))
			info->func[0] |= PMBUS_HAVE_STATUS_FAN12;
	}
	if (pmbus_check_byte_register(client, 0, PMBUS_FAN_CONFIG_34) &&
	    pmbus_check_word_register(client, 0, PMBUS_READ_FAN_SPEED_3)) {
		info->func[0] |= PMBUS_HAVE_FAN34;
		if (pmbus_check_byte_register(client, 0, PMBUS_STATUS_FAN_34))
			info->func[0] |= PMBUS_HAVE_STATUS_FAN34;
	}
	if (pmbus_check_word_register(client, 0, PMBUS_READ_TEMPERATURE_1))
		info->func[0] |= PMBUS_HAVE_TEMP;
	if (pmbus_check_word_register(client, 0, PMBUS_READ_TEMPERATURE_2))
		info->func[0] |= PMBUS_HAVE_TEMP2;
	if (pmbus_check_word_register(client, 0, PMBUS_READ_TEMPERATURE_3))
		info->func[0] |= PMBUS_HAVE_TEMP3;
	if (info->func[0] & (PMBUS_HAVE_TEMP | PMBUS_HAVE_TEMP2
			     | PMBUS_HAVE_TEMP3)
	    && pmbus_check_byte_register(client, 0,
					 PMBUS_STATUS_TEMPERATURE))
			info->func[0] |= PMBUS_HAVE_STATUS_TEMP;

	/* Sensors detected on all pages */
	for (page = 0; page < info->pages; page++) {
		if (pmbus_check_word_register(client, page, PMBUS_READ_VOUT)) {
			info->func[page] |= PMBUS_HAVE_VOUT;
			if (pmbus_check_byte_register(client, page,
						      PMBUS_STATUS_VOUT))
				info->func[page] |= PMBUS_HAVE_STATUS_VOUT;
		}
		if (pmbus_check_word_register(client, page, PMBUS_READ_IOUT)) {
			info->func[page] |= PMBUS_HAVE_IOUT;
			if (pmbus_check_byte_register(client, 0,
						      PMBUS_STATUS_IOUT))
				info->func[page] |= PMBUS_HAVE_STATUS_IOUT;
		}
		if (pmbus_check_word_register(client, page, PMBUS_READ_POUT))
			info->func[page] |= PMBUS_HAVE_POUT;
	}
}

/*
 * Identify chip parameters.
 */
static int pmbus_identify(struct i2c_client *client,
			  struct pmbus_driver_info *info)
{
	int ret = 0;

	if (!info->pages) {
		/*
		 * Check if the PAGE command is supported. If it is,
		 * keep setting the page number until it fails or until the
		 * maximum number of pages has been reached. Assume that
		 * this is the number of pages supported by the chip.
		 */
		if (pmbus_check_byte_register(client, 0, PMBUS_PAGE)) {
			int page;

			for (page = 1; page < PMBUS_PAGES; page++) {
				if (pmbus_set_page(client, page) < 0)
					break;
			}
			pmbus_set_page(client, 0);
			info->pages = page;
		} else {
			info->pages = 1;
		}
	}

	if (pmbus_check_byte_register(client, 0, PMBUS_VOUT_MODE)) {
		int vout_mode;

		vout_mode = pmbus_read_byte_data(client, 0, PMBUS_VOUT_MODE);
		if (vout_mode >= 0 && vout_mode != 0xff) {
			switch (vout_mode >> 5) {
			case 0:
				break;
			case 1:
				info->format[PSC_VOLTAGE_OUT] = vid;
				break;
			case 2:
				info->format[PSC_VOLTAGE_OUT] = direct;
				break;
			default:
				ret = -ENODEV;
				goto abort;
			}
		}
	}

	/*
	 * We should check if the COEFFICIENTS register is supported.
	 * If it is, and the chip is configured for direct mode, we can read
	 * the coefficients from the chip, one set per group of sensor
	 * registers.
	 *
	 * To do this, we will need access to a chip which actually supports the
	 * COEFFICIENTS command, since the command is too complex to implement
	 * without testing it. Until then, abort if a chip configured for direct
	 * mode was detected.
	 */
	if (info->format[PSC_VOLTAGE_OUT] == direct) {
		ret = -ENODEV;
		goto abort;
	}

	/* Try to find sensor groups  */
	pmbus_find_sensor_groups(client, info);
abort:
	return ret;
}

static int pmbus_probe(struct i2c_client *client,
		       const struct i2c_device_id *id)
{
	struct pmbus_driver_info *info;
	int ret;

	info = kzalloc(sizeof(struct pmbus_driver_info), GFP_KERNEL);
	if (!info)
		return -ENOMEM;

	info->pages = id->driver_data;
	info->identify = pmbus_identify;

	ret = pmbus_do_probe(client, id, info);
	if (ret < 0)
		goto out;
	return 0;

out:
	kfree(info);
	return ret;
}

static int pmbus_remove(struct i2c_client *client)
{
	const struct pmbus_driver_info *info;

	info = pmbus_get_driver_info(client);
	pmbus_do_remove(client);
	kfree(info);
	return 0;
}

/*
 * Use driver_data to set the number of pages supported by the chip.
 */
static const struct i2c_device_id pmbus_id[] = {
	{"adp4000", 1},
	{"bmr453", 1},
	{"bmr454", 1},
	{"ncp4200", 1},
	{"ncp4208", 1},
	{"pdt003", 1},
	{"pdt006", 1},
	{"pdt012", 1},
	{"pmbus", 0},
	{"udt020", 1},
	{}
};

MODULE_DEVICE_TABLE(i2c, pmbus_id);

/* This is the driver that will be inserted */
static struct i2c_driver pmbus_driver = {
	.driver = {
		   .name = "pmbus",
		   },
	.probe = pmbus_probe,
	.remove = pmbus_remove,
	.id_table = pmbus_id,
};

module_i2c_driver(pmbus_driver);

MODULE_AUTHOR("Guenter Roeck");
MODULE_DESCRIPTION("Generic PMBus driver");
MODULE_LICENSE("GPL");