1 /* 2 * max8698.c - mfd core driver for the Maxim 8998 3 * 4 * Copyright (C) 2009-2010 Samsung Electronics 5 * Kyungmin Park <kyungmin.park@samsung.com> 6 * Marek Szyprowski <m.szyprowski@samsung.com> 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License as published by 10 * the Free Software Foundation; either version 2 of the License, or 11 * (at your option) any later version. 12 * 13 * This program is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 * GNU General Public License for more details. 17 * 18 * You should have received a copy of the GNU General Public License 19 * along with this program; if not, write to the Free Software 20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 21 */ 22 23 #include <linux/module.h> 24 #include <linux/moduleparam.h> 25 #include <linux/init.h> 26 #include <linux/slab.h> 27 #include <linux/i2c.h> 28 #include <linux/mutex.h> 29 #include <linux/mfd/core.h> 30 #include <linux/mfd/max8998.h> 31 #include <linux/mfd/max8998-private.h> 32 33 static struct mfd_cell max8998_devs[] = { 34 { 35 .name = "max8998-pmic", 36 } 37 }; 38 39 static int max8998_i2c_device_read(struct max8998_dev *max8998, u8 reg, u8 *dest) 40 { 41 struct i2c_client *client = max8998->i2c_client; 42 int ret; 43 44 mutex_lock(&max8998->iolock); 45 ret = i2c_smbus_read_byte_data(client, reg); 46 mutex_unlock(&max8998->iolock); 47 if (ret < 0) 48 return ret; 49 50 ret &= 0xff; 51 *dest = ret; 52 return 0; 53 } 54 55 static int max8998_i2c_device_write(struct max8998_dev *max8998, u8 reg, u8 value) 56 { 57 struct i2c_client *client = max8998->i2c_client; 58 int ret; 59 60 mutex_lock(&max8998->iolock); 61 ret = i2c_smbus_write_byte_data(client, reg, value); 62 mutex_unlock(&max8998->iolock); 63 return ret; 64 } 65 66 static int max8998_i2c_device_update(struct max8998_dev *max8998, u8 reg, 67 u8 val, u8 mask) 68 { 69 struct i2c_client *client = max8998->i2c_client; 70 int ret; 71 72 mutex_lock(&max8998->iolock); 73 ret = i2c_smbus_read_byte_data(client, reg); 74 if (ret >= 0) { 75 u8 old_val = ret & 0xff; 76 u8 new_val = (val & mask) | (old_val & (~mask)); 77 ret = i2c_smbus_write_byte_data(client, reg, new_val); 78 if (ret >= 0) 79 ret = 0; 80 } 81 mutex_unlock(&max8998->iolock); 82 return ret; 83 } 84 85 static int max8998_i2c_probe(struct i2c_client *i2c, 86 const struct i2c_device_id *id) 87 { 88 struct max8998_dev *max8998; 89 int ret = 0; 90 91 max8998 = kzalloc(sizeof(struct max8998_dev), GFP_KERNEL); 92 if (max8998 == NULL) 93 return -ENOMEM; 94 95 i2c_set_clientdata(i2c, max8998); 96 max8998->dev = &i2c->dev; 97 max8998->i2c_client = i2c; 98 max8998->dev_read = max8998_i2c_device_read; 99 max8998->dev_write = max8998_i2c_device_write; 100 max8998->dev_update = max8998_i2c_device_update; 101 mutex_init(&max8998->iolock); 102 103 ret = mfd_add_devices(max8998->dev, -1, 104 max8998_devs, ARRAY_SIZE(max8998_devs), 105 NULL, 0); 106 if (ret < 0) 107 goto err; 108 109 return ret; 110 111 err: 112 mfd_remove_devices(max8998->dev); 113 kfree(max8998); 114 return ret; 115 } 116 117 static int max8998_i2c_remove(struct i2c_client *i2c) 118 { 119 struct max8998_dev *max8998 = i2c_get_clientdata(i2c); 120 121 mfd_remove_devices(max8998->dev); 122 kfree(max8998); 123 124 return 0; 125 } 126 127 static const struct i2c_device_id max8998_i2c_id[] = { 128 { "max8998", 0 }, 129 { } 130 }; 131 MODULE_DEVICE_TABLE(i2c, max8998_i2c_id); 132 133 static struct i2c_driver max8998_i2c_driver = { 134 .driver = { 135 .name = "max8998", 136 .owner = THIS_MODULE, 137 }, 138 .probe = max8998_i2c_probe, 139 .remove = max8998_i2c_remove, 140 .id_table = max8998_i2c_id, 141 }; 142 143 static int __init max8998_i2c_init(void) 144 { 145 return i2c_add_driver(&max8998_i2c_driver); 146 } 147 /* init early so consumer devices can complete system boot */ 148 subsys_initcall(max8998_i2c_init); 149 150 static void __exit max8998_i2c_exit(void) 151 { 152 i2c_del_driver(&max8998_i2c_driver); 153 } 154 module_exit(max8998_i2c_exit); 155 156 MODULE_DESCRIPTION("MAXIM 8998 multi-function core driver"); 157 MODULE_AUTHOR("Kyungmin Park <kyungmin.park@samsung.com>"); 158 MODULE_LICENSE("GPL"); 159