// SPDX-License-Identifier: GPL-2.0-only /* * Simple MFD - I2C * * Author(s): * Michael Walle <michael@walle.cc> * Lee Jones <lee.jones@linaro.org> * * This driver creates a single register map with the intention for it to be * shared by all sub-devices. Children can use their parent's device structure * (dev.parent) in order to reference it. * * Once the register map has been successfully initialised, any sub-devices * represented by child nodes in Device Tree or via the MFD cells in this file * will be subsequently registered. */ #include <linux/i2c.h> #include <linux/kernel.h> #include <linux/mfd/core.h> #include <linux/module.h> #include <linux/of_platform.h> #include <linux/regmap.h> #include "simple-mfd-i2c.h" static const struct regmap_config regmap_config_8r_8v = { .reg_bits = 8, .val_bits = 8, }; static int simple_mfd_i2c_probe(struct i2c_client *i2c) { const struct simple_mfd_data *simple_mfd_data; const struct regmap_config *regmap_config; struct regmap *regmap; int ret; simple_mfd_data = device_get_match_data(&i2c->dev); /* If no regmap_config is specified, use the default 8reg and 8val bits */ if (!simple_mfd_data || !simple_mfd_data->regmap_config) regmap_config = ®map_config_8r_8v; else regmap_config = simple_mfd_data->regmap_config; regmap = devm_regmap_init_i2c(i2c, regmap_config); if (IS_ERR(regmap)) return PTR_ERR(regmap); /* If no MFD cells are spedified, use register the DT child nodes instead */ if (!simple_mfd_data || !simple_mfd_data->mfd_cell) return devm_of_platform_populate(&i2c->dev); ret = devm_mfd_add_devices(&i2c->dev, PLATFORM_DEVID_AUTO, simple_mfd_data->mfd_cell, simple_mfd_data->mfd_cell_size, NULL, 0, NULL); if (ret) dev_err(&i2c->dev, "Failed to add child devices\n"); return ret; } static const struct of_device_id simple_mfd_i2c_of_match[] = { { .compatible = "kontron,sl28cpld" }, {} }; MODULE_DEVICE_TABLE(of, simple_mfd_i2c_of_match); static struct i2c_driver simple_mfd_i2c_driver = { .probe_new = simple_mfd_i2c_probe, .driver = { .name = "simple-mfd-i2c", .of_match_table = simple_mfd_i2c_of_match, }, }; module_i2c_driver(simple_mfd_i2c_driver); MODULE_AUTHOR("Michael Walle <michael@walle.cc>"); MODULE_DESCRIPTION("Simple MFD - I2C driver"); MODULE_LICENSE("GPL v2");