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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * TI/National Semiconductor LP3943 MFD Core Driver4 *5 * Copyright 2013 Texas Instruments6 *7 * Author: Milo Kim <milo.kim@ti.com>8 *9 * Driver structure:10 * LP3943 is an integrated device capable of driving 16 output channels.11 * It can be used for a GPIO expander and PWM generators.12 *13 * LED control General usage for a device14 * ___________ ____________________________15 *16 * LP3943 MFD ---- GPIO expander leds-gpio eg) HW enable pin17 * |18 * --- PWM generator leds-pwm eg) PWM input19 *20 * Internal two PWM channels are used for LED dimming effect.21 * And each output pin can be used as a GPIO as well.22 * The LED functionality can work with GPIOs or PWMs.23 * LEDs can be controlled with legacy leds-gpio(static brightness) or24 * leds-pwm drivers(dynamic brightness control).25 * Alternatively, it can be used for generic GPIO and PWM controller.26 * For example, a GPIO is HW enable pin of a device.27 * A PWM is input pin of a backlight device.28 */29 30#include <linux/err.h>31#include <linux/gpio.h>32#include <linux/i2c.h>33#include <linux/mfd/core.h>34#include <linux/mfd/lp3943.h>35#include <linux/module.h>36#include <linux/of.h>37#include <linux/slab.h>38 39#define LP3943_MAX_REGISTERS 0x0940 41/* Register configuration for pin MUX */42static const struct lp3943_reg_cfg lp3943_mux_cfg[] = {43 /* address, mask, shift */44 { LP3943_REG_MUX0, 0x03, 0 },45 { LP3943_REG_MUX0, 0x0C, 2 },46 { LP3943_REG_MUX0, 0x30, 4 },47 { LP3943_REG_MUX0, 0xC0, 6 },48 { LP3943_REG_MUX1, 0x03, 0 },49 { LP3943_REG_MUX1, 0x0C, 2 },50 { LP3943_REG_MUX1, 0x30, 4 },51 { LP3943_REG_MUX1, 0xC0, 6 },52 { LP3943_REG_MUX2, 0x03, 0 },53 { LP3943_REG_MUX2, 0x0C, 2 },54 { LP3943_REG_MUX2, 0x30, 4 },55 { LP3943_REG_MUX2, 0xC0, 6 },56 { LP3943_REG_MUX3, 0x03, 0 },57 { LP3943_REG_MUX3, 0x0C, 2 },58 { LP3943_REG_MUX3, 0x30, 4 },59 { LP3943_REG_MUX3, 0xC0, 6 },60};61 62static const struct mfd_cell lp3943_devs[] = {63 {64 .name = "lp3943-pwm",65 .of_compatible = "ti,lp3943-pwm",66 },67 {68 .name = "lp3943-gpio",69 .of_compatible = "ti,lp3943-gpio",70 },71};72 73int lp3943_read_byte(struct lp3943 *lp3943, u8 reg, u8 *read)74{75 int ret;76 unsigned int val;77 78 ret = regmap_read(lp3943->regmap, reg, &val);79 if (ret < 0)80 return ret;81 82 *read = (u8)val;83 return 0;84}85EXPORT_SYMBOL_GPL(lp3943_read_byte);86 87int lp3943_write_byte(struct lp3943 *lp3943, u8 reg, u8 data)88{89 return regmap_write(lp3943->regmap, reg, data);90}91EXPORT_SYMBOL_GPL(lp3943_write_byte);92 93int lp3943_update_bits(struct lp3943 *lp3943, u8 reg, u8 mask, u8 data)94{95 return regmap_update_bits(lp3943->regmap, reg, mask, data);96}97EXPORT_SYMBOL_GPL(lp3943_update_bits);98 99static const struct regmap_config lp3943_regmap_config = {100 .reg_bits = 8,101 .val_bits = 8,102 .max_register = LP3943_MAX_REGISTERS,103};104 105static int lp3943_probe(struct i2c_client *cl)106{107 struct lp3943 *lp3943;108 struct device *dev = &cl->dev;109 110 lp3943 = devm_kzalloc(dev, sizeof(*lp3943), GFP_KERNEL);111 if (!lp3943)112 return -ENOMEM;113 114 lp3943->regmap = devm_regmap_init_i2c(cl, &lp3943_regmap_config);115 if (IS_ERR(lp3943->regmap))116 return PTR_ERR(lp3943->regmap);117 118 lp3943->pdata = dev_get_platdata(dev);119 lp3943->dev = dev;120 lp3943->mux_cfg = lp3943_mux_cfg;121 i2c_set_clientdata(cl, lp3943);122 123 return devm_mfd_add_devices(dev, -1, lp3943_devs,124 ARRAY_SIZE(lp3943_devs),125 NULL, 0, NULL);126}127 128static const struct i2c_device_id lp3943_ids[] = {129 { "lp3943" },130 { }131};132MODULE_DEVICE_TABLE(i2c, lp3943_ids);133 134#ifdef CONFIG_OF135static const struct of_device_id lp3943_of_match[] = {136 { .compatible = "ti,lp3943", },137 { }138};139MODULE_DEVICE_TABLE(of, lp3943_of_match);140#endif141 142static struct i2c_driver lp3943_driver = {143 .probe = lp3943_probe,144 .driver = {145 .name = "lp3943",146 .of_match_table = of_match_ptr(lp3943_of_match),147 },148 .id_table = lp3943_ids,149};150 151module_i2c_driver(lp3943_driver);152 153MODULE_DESCRIPTION("LP3943 MFD Core Driver");154MODULE_AUTHOR("Milo Kim");155MODULE_LICENSE("GPL");156