1/* 2 * AD7879-1/AD7889-1 touchscreen (I2C bus) 3 * 4 * Copyright (C) 2008-2010 Michael Hennerich, Analog Devices Inc. 5 * 6 * Licensed under the GPL-2 or later. 7 */ 8 9#include <linux/input.h> /* BUS_I2C */ 10#include <linux/i2c.h> 11#include <linux/module.h> 12#include <linux/types.h> 13 14#include "ad7879.h" 15 16#define AD7879_DEVID 0x79 /* AD7879-1/AD7889-1 */ 17 18#ifdef CONFIG_PM 19static int ad7879_i2c_suspend(struct i2c_client *client, pm_message_t message) 20{ 21 struct ad7879 *ts = i2c_get_clientdata(client); 22 23 ad7879_suspend(ts); 24 25 return 0; 26} 27 28static int ad7879_i2c_resume(struct i2c_client *client) 29{ 30 struct ad7879 *ts = i2c_get_clientdata(client); 31 32 ad7879_resume(ts); 33 34 return 0; 35} 36#else 37# define ad7879_i2c_suspend NULL 38# define ad7879_i2c_resume NULL 39#endif 40 41/* All registers are word-sized. 42 * AD7879 uses a high-byte first convention. 43 */ 44static int ad7879_i2c_read(struct device *dev, u8 reg) 45{ 46 struct i2c_client *client = to_i2c_client(dev); 47 48 return swab16(i2c_smbus_read_word_data(client, reg)); 49} 50 51static int ad7879_i2c_multi_read(struct device *dev, 52 u8 first_reg, u8 count, u16 *buf) 53{ 54 struct i2c_client *client = to_i2c_client(dev); 55 u8 idx; 56 57 i2c_smbus_read_i2c_block_data(client, first_reg, count * 2, (u8 *)buf); 58 59 for (idx = 0; idx < count; ++idx) 60 buf[idx] = swab16(buf[idx]); 61 62 return 0; 63} 64 65static int ad7879_i2c_write(struct device *dev, u8 reg, u16 val) 66{ 67 struct i2c_client *client = to_i2c_client(dev); 68 69 return i2c_smbus_write_word_data(client, reg, swab16(val)); 70} 71 72static const struct ad7879_bus_ops ad7879_i2c_bus_ops = { 73 .bustype = BUS_I2C, 74 .read = ad7879_i2c_read, 75 .multi_read = ad7879_i2c_multi_read, 76 .write = ad7879_i2c_write, 77}; 78 79static int __devinit ad7879_i2c_probe(struct i2c_client *client, 80 const struct i2c_device_id *id) 81{ 82 struct ad7879 *ts; 83 84 if (!i2c_check_functionality(client->adapter, 85 I2C_FUNC_SMBUS_WORD_DATA)) { 86 dev_err(&client->dev, "SMBUS Word Data not Supported\n"); 87 return -EIO; 88 } 89 90 ts = ad7879_probe(&client->dev, AD7879_DEVID, client->irq, 91 &ad7879_i2c_bus_ops); 92 if (IS_ERR(ts)) 93 return PTR_ERR(ts); 94 95 i2c_set_clientdata(client, ts); 96 97 return 0; 98} 99 100static int __devexit ad7879_i2c_remove(struct i2c_client *client) 101{ 102 struct ad7879 *ts = i2c_get_clientdata(client); 103 104 ad7879_remove(ts); 105 106 return 0; 107} 108 109static const struct i2c_device_id ad7879_id[] = { 110 { "ad7879", 0 }, 111 { "ad7889", 0 }, 112 { } 113}; 114MODULE_DEVICE_TABLE(i2c, ad7879_id); 115 116static struct i2c_driver ad7879_i2c_driver = { 117 .driver = { 118 .name = "ad7879", 119 .owner = THIS_MODULE, 120 }, 121 .probe = ad7879_i2c_probe, 122 .remove = __devexit_p(ad7879_i2c_remove), 123 .suspend = ad7879_i2c_suspend, 124 .resume = ad7879_i2c_resume, 125 .id_table = ad7879_id, 126}; 127 128static int __init ad7879_i2c_init(void) 129{ 130 return i2c_add_driver(&ad7879_i2c_driver); 131} 132module_init(ad7879_i2c_init); 133 134static void __exit ad7879_i2c_exit(void) 135{ 136 i2c_del_driver(&ad7879_i2c_driver); 137} 138module_exit(ad7879_i2c_exit); 139 140MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>"); 141MODULE_DESCRIPTION("AD7879(-1) touchscreen I2C bus driver"); 142MODULE_LICENSE("GPL"); 143MODULE_ALIAS("i2c:ad7879"); 144