1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Driver for MPS MPQ8785 Step-Down Converter
4 */
5
6#include <linux/i2c.h>
7#include <linux/bitops.h>
8#include <linux/module.h>
9#include <linux/property.h>
10#include <linux/of_device.h>
11#include "pmbus.h"
12
13#define MPM82504_READ_TEMPERATURE_1_SIGN_POS 9
14
15enum chips { mpm3695, mpm3695_25, mpm82504, mpq8785 };
16
17static u16 voltage_scale_loop_max_val[] = {
18 [mpm3695] = GENMASK(9, 0),
19 [mpm3695_25] = GENMASK(11, 0),
20 [mpm82504] = GENMASK(9, 0),
21 [mpq8785] = GENMASK(10, 0),
22};
23
24static int mpq8785_identify(struct i2c_client *client,
25 struct pmbus_driver_info *info)
26{
27 int vout_mode;
28
29 vout_mode = pmbus_read_byte_data(client, page: 0, reg: PMBUS_VOUT_MODE);
30 if (vout_mode < 0 || vout_mode == 0xff)
31 return vout_mode < 0 ? vout_mode : -ENODEV;
32 switch (vout_mode >> 5) {
33 case 0:
34 info->format[PSC_VOLTAGE_OUT] = linear;
35 break;
36 case 1:
37 case 2:
38 info->format[PSC_VOLTAGE_OUT] = direct;
39 info->m[PSC_VOLTAGE_OUT] = 64;
40 info->b[PSC_VOLTAGE_OUT] = 0;
41 info->R[PSC_VOLTAGE_OUT] = 1;
42 break;
43 default:
44 return -ENODEV;
45 }
46
47 return 0;
48};
49
50static int mpm82504_read_word_data(struct i2c_client *client, int page,
51 int phase, int reg)
52{
53 int ret;
54
55 ret = pmbus_read_word_data(client, page, phase, reg);
56
57 if (ret < 0 || reg != PMBUS_READ_TEMPERATURE_1)
58 return ret;
59
60 /* Fix PMBUS_READ_TEMPERATURE_1 signedness */
61 return sign_extend32(value: ret, MPM82504_READ_TEMPERATURE_1_SIGN_POS) & 0xffff;
62}
63
64static struct pmbus_driver_info mpq8785_info = {
65 .pages = 1,
66 .format[PSC_VOLTAGE_IN] = direct,
67 .format[PSC_CURRENT_OUT] = direct,
68 .format[PSC_TEMPERATURE] = direct,
69 .m[PSC_VOLTAGE_IN] = 4,
70 .b[PSC_VOLTAGE_IN] = 0,
71 .R[PSC_VOLTAGE_IN] = 1,
72 .m[PSC_CURRENT_OUT] = 16,
73 .b[PSC_CURRENT_OUT] = 0,
74 .R[PSC_CURRENT_OUT] = 0,
75 .m[PSC_TEMPERATURE] = 1,
76 .b[PSC_TEMPERATURE] = 0,
77 .R[PSC_TEMPERATURE] = 0,
78 .func[0] =
79 PMBUS_HAVE_VIN | PMBUS_HAVE_STATUS_INPUT |
80 PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT |
81 PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT |
82 PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP,
83};
84
85static const struct i2c_device_id mpq8785_id[] = {
86 { "mpm3695", mpm3695 },
87 { "mpm3695-25", mpm3695_25 },
88 { "mpm82504", mpm82504 },
89 { "mpq8785", mpq8785 },
90 { },
91};
92MODULE_DEVICE_TABLE(i2c, mpq8785_id);
93
94static const struct of_device_id __maybe_unused mpq8785_of_match[] = {
95 { .compatible = "mps,mpm3695", .data = (void *)mpm3695 },
96 { .compatible = "mps,mpm3695-25", .data = (void *)mpm3695_25 },
97 { .compatible = "mps,mpm82504", .data = (void *)mpm82504 },
98 { .compatible = "mps,mpq8785", .data = (void *)mpq8785 },
99 {}
100};
101MODULE_DEVICE_TABLE(of, mpq8785_of_match);
102
103static int mpq8785_probe(struct i2c_client *client)
104{
105 struct device *dev = &client->dev;
106 struct pmbus_driver_info *info;
107 enum chips chip_id;
108 u32 voltage_scale;
109 int ret;
110
111 info = devm_kmemdup(dev, src: &mpq8785_info, len: sizeof(*info), GFP_KERNEL);
112 if (!info)
113 return -ENOMEM;
114
115 if (dev->of_node)
116 chip_id = (kernel_ulong_t)of_device_get_match_data(dev);
117 else
118 chip_id = (kernel_ulong_t)i2c_get_match_data(client);
119
120 switch (chip_id) {
121 case mpm3695:
122 case mpm3695_25:
123 case mpm82504:
124 info->format[PSC_VOLTAGE_OUT] = direct;
125 info->m[PSC_VOLTAGE_OUT] = 8;
126 info->b[PSC_VOLTAGE_OUT] = 0;
127 info->R[PSC_VOLTAGE_OUT] = 2;
128 info->read_word_data = mpm82504_read_word_data;
129 break;
130 case mpq8785:
131 info->identify = mpq8785_identify;
132 break;
133 default:
134 return -ENODEV;
135 }
136
137 if (!device_property_read_u32(dev, propname: "mps,vout-fb-divider-ratio-permille",
138 val: &voltage_scale)) {
139 if (voltage_scale > voltage_scale_loop_max_val[chip_id])
140 return -EINVAL;
141
142 ret = i2c_smbus_write_word_data(client, command: PMBUS_VOUT_SCALE_LOOP,
143 value: voltage_scale);
144 if (ret)
145 return ret;
146 }
147
148 return pmbus_do_probe(client, info);
149};
150
151static struct i2c_driver mpq8785_driver = {
152 .driver = {
153 .name = "mpq8785",
154 .of_match_table = of_match_ptr(mpq8785_of_match),
155 },
156 .probe = mpq8785_probe,
157 .id_table = mpq8785_id,
158};
159
160module_i2c_driver(mpq8785_driver);
161
162MODULE_AUTHOR("Charles Hsu <ythsu0511@gmail.com>");
163MODULE_DESCRIPTION("PMBus driver for MPS MPQ8785");
164MODULE_LICENSE("GPL");
165MODULE_IMPORT_NS("PMBUS");
166

source code of linux/drivers/hwmon/pmbus/mpq8785.c