1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * mpq7932.c - hwmon with optional regulator driver for mps mpq7932
4 * Copyright 2022 Monolithic Power Systems, Inc
5 *
6 * Author: Saravanan Sekar <saravanan@linumiz.com>
7 */
8
9 #include <linux/bits.h>
10 #include <linux/err.h>
11 #include <linux/i2c.h>
12 #include <linux/init.h>
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/of.h>
16 #include <linux/pmbus.h>
17 #include "pmbus.h"
18
19 #define MPQ7932_BUCK_UV_MIN 206250
20 #define MPQ7932_UV_STEP 6250
21 #define MPQ7932_N_VOLTAGES 256
22 #define MPQ7932_VOUT_MAX 0xFF
23 #define MPQ7932_NUM_PAGES 6
24 #define MPQ2286_NUM_PAGES 1
25
26 #define MPQ7932_TON_DELAY 0x60
27 #define MPQ7932_VOUT_STARTUP_SLEW 0xA3
28 #define MPQ7932_VOUT_SHUTDOWN_SLEW 0xA5
29 #define MPQ7932_VOUT_SLEW_MASK GENMASK(1, 0)
30 #define MPQ7932_TON_DELAY_MASK GENMASK(4, 0)
31
32 struct mpq7932_data {
33 struct pmbus_driver_info info;
34 struct pmbus_platform_data pdata;
35 };
36
37 #if IS_ENABLED(CONFIG_SENSORS_MPQ7932_REGULATOR)
38 static const struct regulator_desc mpq7932_regulators_desc[] = {
39 PMBUS_REGULATOR_STEP("buck", 0, MPQ7932_N_VOLTAGES,
40 MPQ7932_UV_STEP, MPQ7932_BUCK_UV_MIN),
41 PMBUS_REGULATOR_STEP("buck", 1, MPQ7932_N_VOLTAGES,
42 MPQ7932_UV_STEP, MPQ7932_BUCK_UV_MIN),
43 PMBUS_REGULATOR_STEP("buck", 2, MPQ7932_N_VOLTAGES,
44 MPQ7932_UV_STEP, MPQ7932_BUCK_UV_MIN),
45 PMBUS_REGULATOR_STEP("buck", 3, MPQ7932_N_VOLTAGES,
46 MPQ7932_UV_STEP, MPQ7932_BUCK_UV_MIN),
47 PMBUS_REGULATOR_STEP("buck", 4, MPQ7932_N_VOLTAGES,
48 MPQ7932_UV_STEP, MPQ7932_BUCK_UV_MIN),
49 PMBUS_REGULATOR_STEP("buck", 5, MPQ7932_N_VOLTAGES,
50 MPQ7932_UV_STEP, MPQ7932_BUCK_UV_MIN),
51 };
52
53 static const struct regulator_desc mpq7932_regulators_desc_one[] = {
54 PMBUS_REGULATOR_STEP_ONE("buck", MPQ7932_N_VOLTAGES,
55 MPQ7932_UV_STEP, MPQ7932_BUCK_UV_MIN),
56 };
57 #endif
58
mpq7932_write_word_data(struct i2c_client * client,int page,int reg,u16 word)59 static int mpq7932_write_word_data(struct i2c_client *client, int page, int reg,
60 u16 word)
61 {
62 switch (reg) {
63 /*
64 * chip supports only byte access for VOUT_COMMAND otherwise
65 * access results -EREMOTEIO
66 */
67 case PMBUS_VOUT_COMMAND:
68 return pmbus_write_byte_data(client, page, reg, word & 0xFF);
69
70 default:
71 return -ENODATA;
72 }
73 }
74
mpq7932_read_word_data(struct i2c_client * client,int page,int phase,int reg)75 static int mpq7932_read_word_data(struct i2c_client *client, int page,
76 int phase, int reg)
77 {
78 switch (reg) {
79 /*
80 * chip supports neither (PMBUS_VOUT_MARGIN_HIGH, PMBUS_VOUT_MARGIN_LOW)
81 * nor (PMBUS_MFR_VOUT_MIN, PMBUS_MFR_VOUT_MAX). As a result set voltage
82 * fails due to error in pmbus_regulator_get_low_margin, so faked.
83 */
84 case PMBUS_MFR_VOUT_MIN:
85 return 0;
86
87 case PMBUS_MFR_VOUT_MAX:
88 return MPQ7932_VOUT_MAX;
89
90 /*
91 * chip supports only byte access for VOUT_COMMAND otherwise
92 * access results in -EREMOTEIO
93 */
94 case PMBUS_READ_VOUT:
95 return pmbus_read_byte_data(client, page, PMBUS_VOUT_COMMAND);
96
97 default:
98 return -ENODATA;
99 }
100 }
101
mpq7932_probe(struct i2c_client * client)102 static int mpq7932_probe(struct i2c_client *client)
103 {
104 struct mpq7932_data *data;
105 struct pmbus_driver_info *info;
106 struct device *dev = &client->dev;
107 int i;
108
109 data = devm_kzalloc(dev, sizeof(struct mpq7932_data), GFP_KERNEL);
110 if (!data)
111 return -ENOMEM;
112
113 info = &data->info;
114 info->pages = (int)(unsigned long)device_get_match_data(&client->dev);
115 info->format[PSC_VOLTAGE_OUT] = direct;
116 info->m[PSC_VOLTAGE_OUT] = 160;
117 info->b[PSC_VOLTAGE_OUT] = -33;
118 for (i = 0; i < info->pages; i++) {
119 info->func[i] = PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT
120 | PMBUS_HAVE_STATUS_TEMP;
121 }
122
123 #if IS_ENABLED(CONFIG_SENSORS_MPQ7932_REGULATOR)
124 info->num_regulators = info->pages;
125 if (info->num_regulators == 1)
126 info->reg_desc = mpq7932_regulators_desc_one;
127 else
128 info->reg_desc = mpq7932_regulators_desc;
129 #endif
130
131 info->read_word_data = mpq7932_read_word_data;
132 info->write_word_data = mpq7932_write_word_data;
133
134 data->pdata.flags = PMBUS_NO_CAPABILITY;
135 dev->platform_data = &data->pdata;
136
137 return pmbus_do_probe(client, info);
138 }
139
140 static const struct of_device_id mpq7932_of_match[] = {
141 { .compatible = "mps,mpq2286", .data = (void *)MPQ2286_NUM_PAGES },
142 { .compatible = "mps,mpq7932", .data = (void *)MPQ7932_NUM_PAGES },
143 {},
144 };
145 MODULE_DEVICE_TABLE(of, mpq7932_of_match);
146
147 static const struct i2c_device_id mpq7932_id[] = {
148 { "mpq2286", },
149 { "mpq7932", },
150 { },
151 };
152 MODULE_DEVICE_TABLE(i2c, mpq7932_id);
153
154 static struct i2c_driver mpq7932_regulator_driver = {
155 .driver = {
156 .name = "mpq7932",
157 .of_match_table = mpq7932_of_match,
158 },
159 .probe = mpq7932_probe,
160 .id_table = mpq7932_id,
161 };
162 module_i2c_driver(mpq7932_regulator_driver);
163
164 MODULE_AUTHOR("Saravanan Sekar <saravanan@linumiz.com>");
165 MODULE_DESCRIPTION("MPQ7932 PMIC regulator driver");
166 MODULE_LICENSE("GPL");
167 MODULE_IMPORT_NS(PMBUS);
168