1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Simple MFD - I2C
  4 *
  5 * Author(s):
  6 * 	Michael Walle <michael@walle.cc>
  7 * 	Lee Jones <lee.jones@linaro.org>
  8 *
  9 * This driver creates a single register map with the intention for it to be
 10 * shared by all sub-devices.  Children can use their parent's device structure
 11 * (dev.parent) in order to reference it.
 12 *
 13 * Once the register map has been successfully initialised, any sub-devices
 14 * represented by child nodes in Device Tree or via the MFD cells in this file
 15 * will be subsequently registered.
 16 */
 17
 18#include <linux/i2c.h>
 19#include <linux/kernel.h>
 20#include <linux/mfd/core.h>
 21#include <linux/module.h>
 22#include <linux/of_platform.h>
 23#include <linux/regmap.h>
 24
 25#include "simple-mfd-i2c.h"
 26
 27static const struct regmap_config regmap_config_8r_8v = {
 28	.reg_bits = 8,
 29	.val_bits = 8,
 30};
 31
 32static int simple_mfd_i2c_probe(struct i2c_client *i2c)
 33{
 34	const struct simple_mfd_data *simple_mfd_data;
 35	const struct regmap_config *regmap_config;
 36	struct regmap *regmap;
 37	int ret;
 38
 39	simple_mfd_data = device_get_match_data(&i2c->dev);
 40
 41	/* If no regmap_config is specified, use the default 8reg and 8val bits */
 42	if (!simple_mfd_data || !simple_mfd_data->regmap_config)
 43		regmap_config = &regmap_config_8r_8v;
 44	else
 45		regmap_config = simple_mfd_data->regmap_config;
 46
 47	regmap = devm_regmap_init_i2c(i2c, regmap_config);
 48	if (IS_ERR(regmap))
 49		return PTR_ERR(regmap);
 50
 51	/* If no MFD cells are specified, register using the DT child nodes instead */
 52	if (!simple_mfd_data || !simple_mfd_data->mfd_cell)
 53		return devm_of_platform_populate(&i2c->dev);
 54
 55	ret = devm_mfd_add_devices(&i2c->dev, PLATFORM_DEVID_AUTO,
 56				   simple_mfd_data->mfd_cell,
 57				   simple_mfd_data->mfd_cell_size,
 58				   NULL, 0, NULL);
 59	if (ret)
 60		dev_err(&i2c->dev, "Failed to add child devices\n");
 61
 62	return ret;
 63}
 64
 65static const struct mfd_cell sy7636a_cells[] = {
 66	{ .name = "sy7636a-regulator", },
 67	{ .name = "sy7636a-temperature", },
 68};
 69
 70static const struct simple_mfd_data silergy_sy7636a = {
 71	.mfd_cell = sy7636a_cells,
 72	.mfd_cell_size = ARRAY_SIZE(sy7636a_cells),
 73};
 74
 75static const struct mfd_cell max5970_cells[] = {
 76	{ .name = "max5970-regulator", },
 77	{ .name = "max5970-iio", },
 78	{ .name = "max5970-led", },
 79};
 80
 81static const struct simple_mfd_data maxim_max5970 = {
 82	.mfd_cell = max5970_cells,
 83	.mfd_cell_size = ARRAY_SIZE(max5970_cells),
 84};
 85
 86static const struct of_device_id simple_mfd_i2c_of_match[] = {
 87	{ .compatible = "kontron,sl28cpld" },
 88	{ .compatible = "silergy,sy7636a", .data = &silergy_sy7636a},
 89	{ .compatible = "maxim,max5970", .data = &maxim_max5970},
 90	{ .compatible = "maxim,max5978", .data = &maxim_max5970},
 91	{}
 92};
 93MODULE_DEVICE_TABLE(of, simple_mfd_i2c_of_match);
 94
 95static struct i2c_driver simple_mfd_i2c_driver = {
 96	.probe = simple_mfd_i2c_probe,
 97	.driver = {
 98		.name = "simple-mfd-i2c",
 99		.of_match_table = simple_mfd_i2c_of_match,
100	},
101};
102module_i2c_driver(simple_mfd_i2c_driver);
103
104MODULE_AUTHOR("Michael Walle <michael@walle.cc>");
105MODULE_DESCRIPTION("Simple MFD - I2C driver");
106MODULE_LICENSE("GPL v2");