summaryrefslogtreecommitdiff
path: root/drivers/hwmon/pmbus/mp5990.c
blob: 5d1d5eac89daa931bcd992de0cb05fce87abba20 (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
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Driver for MPS MP5990 Hot-Swap Controller
 */

#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/of_device.h>
#include "pmbus.h"

#define MP5990_EFUSE_CFG	(0xC4)
#define MP5990_VOUT_FORMAT	BIT(9)

struct mp5990_data {
	struct pmbus_driver_info info;
	u8 vout_mode;
	u8 vout_linear_exponent;
};

#define to_mp5990_data(x)  container_of(x, struct mp5990_data, info)

static int mp5990_read_byte_data(struct i2c_client *client, int page, int reg)
{
	const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
	struct mp5990_data *data = to_mp5990_data(info);

	switch (reg) {
	case PMBUS_VOUT_MODE:
		if (data->vout_mode == linear) {
			/*
			 * The VOUT format used by the chip is linear11,
			 * not linear16. Report that VOUT is in linear mode
			 * and return exponent value extracted while probing
			 * the chip.
			 */
			return data->vout_linear_exponent;
		}

		/*
		 * The datasheet does not support the VOUT command,
		 * but the device responds with a default value of 0x17.
		 * In the standard, 0x17 represents linear mode.
		 * Therefore, we should report that VOUT is in direct
		 * format when the chip is configured for it.
		 */
		return PB_VOUT_MODE_DIRECT;

	default:
		return -ENODATA;
	}
}

static int mp5990_read_word_data(struct i2c_client *client, int page,
				 int phase, int reg)
{
	const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
	struct mp5990_data *data = to_mp5990_data(info);
	int ret;
	s32 mantissa;

	switch (reg) {
	case PMBUS_READ_VOUT:
		ret = pmbus_read_word_data(client, page, phase, reg);
		if (ret < 0)
			return ret;
		/*
		 * Because the VOUT format used by the chip is linear11 and not
		 * linear16, we disregard bits[15:11]. The exponent is reported
		 * as part of the VOUT_MODE command.
		 */
		if (data->vout_mode == linear) {
			mantissa = ((s16)((ret & 0x7ff) << 5)) >> 5;
			ret = mantissa;
		}
		break;
	default:
		return -ENODATA;
	}

	return ret;
}

static struct pmbus_driver_info mp5990_info = {
	.pages = 1,
	.format[PSC_VOLTAGE_IN] = direct,
	.format[PSC_VOLTAGE_OUT] = direct,
	.format[PSC_CURRENT_OUT] = direct,
	.format[PSC_POWER] = direct,
	.format[PSC_TEMPERATURE] = direct,
	.m[PSC_VOLTAGE_IN] = 32,
	.b[PSC_VOLTAGE_IN] = 0,
	.R[PSC_VOLTAGE_IN] = 0,
	.m[PSC_VOLTAGE_OUT] = 32,
	.b[PSC_VOLTAGE_OUT] = 0,
	.R[PSC_VOLTAGE_OUT] = 0,
	.m[PSC_CURRENT_OUT] = 16,
	.b[PSC_CURRENT_OUT] = 0,
	.R[PSC_CURRENT_OUT] = 0,
	.m[PSC_POWER] = 1,
	.b[PSC_POWER] = 0,
	.R[PSC_POWER] = 0,
	.m[PSC_TEMPERATURE] = 1,
	.b[PSC_TEMPERATURE] = 0,
	.R[PSC_TEMPERATURE] = 0,
	.func[0] =
		PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | PMBUS_HAVE_PIN |
		PMBUS_HAVE_TEMP | PMBUS_HAVE_IOUT |
		PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP,
	.read_byte_data = mp5990_read_byte_data,
	.read_word_data = mp5990_read_word_data,
};

static int mp5990_probe(struct i2c_client *client)
{
	struct pmbus_driver_info *info;
	struct mp5990_data *data;
	int ret;

	data = devm_kzalloc(&client->dev, sizeof(struct mp5990_data),
			    GFP_KERNEL);
	if (!data)
		return -ENOMEM;

	memcpy(&data->info, &mp5990_info, sizeof(*info));
	info = &data->info;

	/* Read Vout Config */
	ret = i2c_smbus_read_word_data(client, MP5990_EFUSE_CFG);
	if (ret < 0) {
		dev_err(&client->dev, "Can't get vout mode.");
		return ret;
	}

	/*
	 * EFUSE_CFG (0xC4) bit9=1 is linear mode, bit=0 is direct mode.
	 */
	if (ret & MP5990_VOUT_FORMAT) {
		data->vout_mode = linear;
		data->info.format[PSC_VOLTAGE_IN] = linear;
		data->info.format[PSC_VOLTAGE_OUT] = linear;
		data->info.format[PSC_CURRENT_OUT] = linear;
		data->info.format[PSC_POWER] = linear;
		ret = i2c_smbus_read_word_data(client, PMBUS_READ_VOUT);
		if (ret < 0) {
			dev_err(&client->dev, "Can't get vout exponent.");
			return ret;
		}
		data->vout_linear_exponent = (u8)((ret >> 11) & 0x1f);
	} else {
		data->vout_mode = direct;
	}
	return pmbus_do_probe(client, info);
}

static const struct of_device_id mp5990_of_match[] = {
	{ .compatible = "mps,mp5990" },
	{}
};

static const struct i2c_device_id mp5990_id[] = {
	{"mp5990"},
	{ }
};
MODULE_DEVICE_TABLE(i2c, mp5990_id);

static struct i2c_driver mp5990_driver = {
	.driver = {
		   .name = "mp5990",
		   .of_match_table = mp5990_of_match,
	},
	.probe = mp5990_probe,
	.id_table = mp5990_id,
};
module_i2c_driver(mp5990_driver);

MODULE_AUTHOR("Peter Yin <peter.yin@quantatw.com>");
MODULE_DESCRIPTION("PMBus driver for MP5990 HSC");
MODULE_LICENSE("GPL");
MODULE_IMPORT_NS(PMBUS);