xref: /linux/drivers/hwmon/pmbus/mpq7932.c (revision 0678df8271820bcf8fb4f877129f05d68a237de4)
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 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 
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 
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 
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