mpq7932.c

  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
 32struct mpq7932_data {
 33	struct pmbus_driver_info info;
 34	struct pmbus_platform_data pdata;
 35};
 36
 37#if IS_ENABLED(CONFIG_SENSORS_MPQ7932_REGULATOR)
 38static 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
 53static const struct regulator_desc mpq7932_regulators_desc_one[] = {
 54	PMBUS_REGULATOR_STEP_ONE_NODE("buck", MPQ7932_N_VOLTAGES,
 55				      MPQ7932_UV_STEP, MPQ7932_BUCK_UV_MIN),
 56};
 57#endif
 58
 59static 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
 75static 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
102static 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
140static 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};
145MODULE_DEVICE_TABLE(of, mpq7932_of_match);
146
147static const struct i2c_device_id mpq7932_id[] = {
148	{ "mpq2286", },
149	{ "mpq7932", },
150	{ },
151};
152MODULE_DEVICE_TABLE(i2c, mpq7932_id);
153
154static 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};
162module_i2c_driver(mpq7932_regulator_driver);
163
164MODULE_AUTHOR("Saravanan Sekar <saravanan@linumiz.com>");
165MODULE_DESCRIPTION("MPQ7932 PMIC regulator driver");
166MODULE_LICENSE("GPL");
167MODULE_IMPORT_NS("PMBUS");