/* * I2C driver for Maxim MAX8925 * * Copyright (C) 2009 Marvell International Ltd. * Haojian Zhuang <haojian.zhuang@marvell.com> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ #include <linux/kernel.h> #include <linux/module.h> #include <linux/platform_device.h> #include <linux/i2c.h> #include <linux/mfd/max8925.h> #include <linux/slab.h> #define RTC_I2C_ADDR 0x68 #define ADC_I2C_ADDR 0x47 static inline int max8925_read_device(struct i2c_client *i2c, int reg, int bytes, void *dest) { int ret; if (bytes > 1) ret = i2c_smbus_read_i2c_block_data(i2c, reg, bytes, dest); else { ret = i2c_smbus_read_byte_data(i2c, reg); if (ret < 0) return ret; *(unsigned char *)dest = (unsigned char)ret; } return ret; } static inline int max8925_write_device(struct i2c_client *i2c, int reg, int bytes, void *src) { unsigned char buf[9]; int ret; buf[0] = (unsigned char)reg; memcpy(&buf[1], src, bytes); ret = i2c_master_send(i2c, buf, bytes + 1); if (ret < 0) return ret; return 0; } int max8925_reg_read(struct i2c_client *i2c, int reg) { struct max8925_chip *chip = i2c_get_clientdata(i2c); unsigned char data = 0; int ret; mutex_lock(&chip->io_lock); ret = max8925_read_device(i2c, reg, 1, &data); mutex_unlock(&chip->io_lock); if (ret < 0) return ret; else return (int)data; } EXPORT_SYMBOL(max8925_reg_read); int max8925_reg_write(struct i2c_client *i2c, int reg, unsigned char data) { struct max8925_chip *chip = i2c_get_clientdata(i2c); int ret; mutex_lock(&chip->io_lock); ret = max8925_write_device(i2c, reg, 1, &data); mutex_unlock(&chip->io_lock); return ret; } EXPORT_SYMBOL(max8925_reg_write); int max8925_bulk_read(struct i2c_client *i2c, int reg, int count, unsigned char *buf) { struct max8925_chip *chip = i2c_get_clientdata(i2c); int ret; mutex_lock(&chip->io_lock); ret = max8925_read_device(i2c, reg, count, buf); mutex_unlock(&chip->io_lock); return ret; } EXPORT_SYMBOL(max8925_bulk_read); int max8925_bulk_write(struct i2c_client *i2c, int reg, int count, unsigned char *buf) { struct max8925_chip *chip = i2c_get_clientdata(i2c); int ret; mutex_lock(&chip->io_lock); ret = max8925_write_device(i2c, reg, count, buf); mutex_unlock(&chip->io_lock); return ret; } EXPORT_SYMBOL(max8925_bulk_write); int max8925_set_bits(struct i2c_client *i2c, int reg, unsigned char mask, unsigned char data) { struct max8925_chip *chip = i2c_get_clientdata(i2c); unsigned char value; int ret; mutex_lock(&chip->io_lock); ret = max8925_read_device(i2c, reg, 1, &value); if (ret < 0) goto out; value &= ~mask; value |= data; ret = max8925_write_device(i2c, reg, 1, &value); out: mutex_unlock(&chip->io_lock); return ret; } EXPORT_SYMBOL(max8925_set_bits); static const struct i2c_device_id max8925_id_table[] = { { "max8925", 0 }, { }, }; MODULE_DEVICE_TABLE(i2c, max8925_id_table); static int max8925_dt_init(struct device_node *np, struct device *dev, struct max8925_platform_data *pdata) { int ret; ret = of_property_read_u32(np, "maxim,tsc-irq", &pdata->tsc_irq); if (ret) { dev_err(dev, "Not found maxim,tsc-irq property\n"); return -EINVAL; } return 0; } static int max8925_probe(struct i2c_client *client, const struct i2c_device_id *id) { struct max8925_platform_data *pdata = dev_get_platdata(&client->dev); static struct max8925_chip *chip; struct device_node *node = client->dev.of_node; if (node && !pdata) { /* parse DT to get platform data */ pdata = devm_kzalloc(&client->dev, sizeof(struct max8925_platform_data), GFP_KERNEL); if (!pdata) return -ENOMEM; if (max8925_dt_init(node, &client->dev, pdata)) return -EINVAL; } else if (!pdata) { pr_info("%s: platform data is missing\n", __func__); return -EINVAL; } chip = devm_kzalloc(&client->dev, sizeof(struct max8925_chip), GFP_KERNEL); if (chip == NULL) return -ENOMEM; chip->i2c = client; chip->dev = &client->dev; i2c_set_clientdata(client, chip); dev_set_drvdata(chip->dev, chip); mutex_init(&chip->io_lock); chip->rtc = i2c_new_dummy(chip->i2c->adapter, RTC_I2C_ADDR); if (!chip->rtc) { dev_err(chip->dev, "Failed to allocate I2C device for RTC\n"); return -ENODEV; } i2c_set_clientdata(chip->rtc, chip); chip->adc = i2c_new_dummy(chip->i2c->adapter, ADC_I2C_ADDR); if (!chip->adc) { dev_err(chip->dev, "Failed to allocate I2C device for ADC\n"); i2c_unregister_device(chip->rtc); return -ENODEV; } i2c_set_clientdata(chip->adc, chip); device_init_wakeup(&client->dev, 1); max8925_device_init(chip, pdata); return 0; } static int max8925_remove(struct i2c_client *client) { struct max8925_chip *chip = i2c_get_clientdata(client); max8925_device_exit(chip); i2c_unregister_device(chip->adc); i2c_unregister_device(chip->rtc); return 0; } #ifdef CONFIG_PM_SLEEP static int max8925_suspend(struct device *dev) { struct i2c_client *client = container_of(dev, struct i2c_client, dev); struct max8925_chip *chip = i2c_get_clientdata(client); if (device_may_wakeup(dev) && chip->wakeup_flag) enable_irq_wake(chip->core_irq); return 0; } static int max8925_resume(struct device *dev) { struct i2c_client *client = container_of(dev, struct i2c_client, dev); struct max8925_chip *chip = i2c_get_clientdata(client); if (device_may_wakeup(dev) && chip->wakeup_flag) disable_irq_wake(chip->core_irq); return 0; } #endif static SIMPLE_DEV_PM_OPS(max8925_pm_ops, max8925_suspend, max8925_resume); static const struct of_device_id max8925_dt_ids[] = { { .compatible = "maxim,max8925", }, {}, }; MODULE_DEVICE_TABLE(of, max8925_dt_ids); static struct i2c_driver max8925_driver = { .driver = { .name = "max8925", .owner = THIS_MODULE, .pm = &max8925_pm_ops, .of_match_table = max8925_dt_ids, }, .probe = max8925_probe, .remove = max8925_remove, .id_table = max8925_id_table, }; static int __init max8925_i2c_init(void) { int ret; ret = i2c_add_driver(&max8925_driver); if (ret != 0) pr_err("Failed to register MAX8925 I2C driver: %d\n", ret); return ret; } subsys_initcall(max8925_i2c_init); static void __exit max8925_i2c_exit(void) { i2c_del_driver(&max8925_driver); } module_exit(max8925_i2c_exit); MODULE_DESCRIPTION("I2C Driver for Maxim 8925"); MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>"); MODULE_LICENSE("GPL");