1 /* 2 * wm8350-i2c.c -- Generic I2C driver for Wolfson WM8350 PMIC 3 * 4 * Copyright 2007, 2008 Wolfson Microelectronics PLC. 5 * 6 * Author: Liam Girdwood 7 * linux@wolfsonmicro.com 8 * 9 * This program is free software; you can redistribute it and/or modify it 10 * under the terms of the GNU General Public License as published by the 11 * Free Software Foundation; either version 2 of the License, or (at your 12 * option) any later version. 13 * 14 */ 15 16 #include <linux/module.h> 17 #include <linux/moduleparam.h> 18 #include <linux/init.h> 19 #include <linux/i2c.h> 20 #include <linux/platform_device.h> 21 #include <linux/mfd/wm8350/core.h> 22 #include <linux/slab.h> 23 24 static int wm8350_i2c_read_device(struct wm8350 *wm8350, char reg, 25 int bytes, void *dest) 26 { 27 int ret; 28 29 ret = i2c_master_send(wm8350->i2c_client, ®, 1); 30 if (ret < 0) 31 return ret; 32 ret = i2c_master_recv(wm8350->i2c_client, dest, bytes); 33 if (ret < 0) 34 return ret; 35 if (ret != bytes) 36 return -EIO; 37 return 0; 38 } 39 40 static int wm8350_i2c_write_device(struct wm8350 *wm8350, char reg, 41 int bytes, void *src) 42 { 43 /* we add 1 byte for device register */ 44 u8 msg[(WM8350_MAX_REGISTER << 1) + 1]; 45 int ret; 46 47 if (bytes > ((WM8350_MAX_REGISTER << 1) + 1)) 48 return -EINVAL; 49 50 msg[0] = reg; 51 memcpy(&msg[1], src, bytes); 52 ret = i2c_master_send(wm8350->i2c_client, msg, bytes + 1); 53 if (ret < 0) 54 return ret; 55 if (ret != bytes + 1) 56 return -EIO; 57 return 0; 58 } 59 60 static int wm8350_i2c_probe(struct i2c_client *i2c, 61 const struct i2c_device_id *id) 62 { 63 struct wm8350 *wm8350; 64 int ret = 0; 65 66 wm8350 = kzalloc(sizeof(struct wm8350), GFP_KERNEL); 67 if (wm8350 == NULL) 68 return -ENOMEM; 69 70 i2c_set_clientdata(i2c, wm8350); 71 wm8350->dev = &i2c->dev; 72 wm8350->i2c_client = i2c; 73 wm8350->read_dev = wm8350_i2c_read_device; 74 wm8350->write_dev = wm8350_i2c_write_device; 75 76 ret = wm8350_device_init(wm8350, i2c->irq, i2c->dev.platform_data); 77 if (ret < 0) 78 goto err; 79 80 return ret; 81 82 err: 83 kfree(wm8350); 84 return ret; 85 } 86 87 static int wm8350_i2c_remove(struct i2c_client *i2c) 88 { 89 struct wm8350 *wm8350 = i2c_get_clientdata(i2c); 90 91 wm8350_device_exit(wm8350); 92 kfree(wm8350); 93 94 return 0; 95 } 96 97 static const struct i2c_device_id wm8350_i2c_id[] = { 98 { "wm8350", 0 }, 99 { "wm8351", 0 }, 100 { "wm8352", 0 }, 101 { } 102 }; 103 MODULE_DEVICE_TABLE(i2c, wm8350_i2c_id); 104 105 106 static struct i2c_driver wm8350_i2c_driver = { 107 .driver = { 108 .name = "wm8350", 109 .owner = THIS_MODULE, 110 }, 111 .probe = wm8350_i2c_probe, 112 .remove = wm8350_i2c_remove, 113 .id_table = wm8350_i2c_id, 114 }; 115 116 static int __init wm8350_i2c_init(void) 117 { 118 return i2c_add_driver(&wm8350_i2c_driver); 119 } 120 /* init early so consumer devices can complete system boot */ 121 subsys_initcall(wm8350_i2c_init); 122 123 static void __exit wm8350_i2c_exit(void) 124 { 125 i2c_del_driver(&wm8350_i2c_driver); 126 } 127 module_exit(wm8350_i2c_exit); 128 129 MODULE_DESCRIPTION("I2C support for the WM8350 AudioPlus PMIC"); 130 MODULE_LICENSE("GPL"); 131