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 #include <linux/pm.h> 14 15 #include "ad7879.h" 16 17 #define AD7879_DEVID 0x79 /* AD7879-1/AD7889-1 */ 18 19 /* All registers are word-sized. 20 * AD7879 uses a high-byte first convention. 21 */ 22 static int ad7879_i2c_read(struct device *dev, u8 reg) 23 { 24 struct i2c_client *client = to_i2c_client(dev); 25 26 return i2c_smbus_read_word_swapped(client, reg); 27 } 28 29 static int ad7879_i2c_multi_read(struct device *dev, 30 u8 first_reg, u8 count, u16 *buf) 31 { 32 struct i2c_client *client = to_i2c_client(dev); 33 u8 idx; 34 35 i2c_smbus_read_i2c_block_data(client, first_reg, count * 2, (u8 *)buf); 36 37 for (idx = 0; idx < count; ++idx) 38 buf[idx] = swab16(buf[idx]); 39 40 return 0; 41 } 42 43 static int ad7879_i2c_write(struct device *dev, u8 reg, u16 val) 44 { 45 struct i2c_client *client = to_i2c_client(dev); 46 47 return i2c_smbus_write_word_swapped(client, reg, val); 48 } 49 50 static const struct ad7879_bus_ops ad7879_i2c_bus_ops = { 51 .bustype = BUS_I2C, 52 .read = ad7879_i2c_read, 53 .multi_read = ad7879_i2c_multi_read, 54 .write = ad7879_i2c_write, 55 }; 56 57 static int ad7879_i2c_probe(struct i2c_client *client, 58 const struct i2c_device_id *id) 59 { 60 struct ad7879 *ts; 61 62 if (!i2c_check_functionality(client->adapter, 63 I2C_FUNC_SMBUS_WORD_DATA)) { 64 dev_err(&client->dev, "SMBUS Word Data not Supported\n"); 65 return -EIO; 66 } 67 68 ts = ad7879_probe(&client->dev, AD7879_DEVID, client->irq, 69 &ad7879_i2c_bus_ops); 70 if (IS_ERR(ts)) 71 return PTR_ERR(ts); 72 73 i2c_set_clientdata(client, ts); 74 75 return 0; 76 } 77 78 static int ad7879_i2c_remove(struct i2c_client *client) 79 { 80 struct ad7879 *ts = i2c_get_clientdata(client); 81 82 ad7879_remove(ts); 83 84 return 0; 85 } 86 87 static const struct i2c_device_id ad7879_id[] = { 88 { "ad7879", 0 }, 89 { "ad7889", 0 }, 90 { } 91 }; 92 MODULE_DEVICE_TABLE(i2c, ad7879_id); 93 94 static struct i2c_driver ad7879_i2c_driver = { 95 .driver = { 96 .name = "ad7879", 97 .pm = &ad7879_pm_ops, 98 }, 99 .probe = ad7879_i2c_probe, 100 .remove = ad7879_i2c_remove, 101 .id_table = ad7879_id, 102 }; 103 104 module_i2c_driver(ad7879_i2c_driver); 105 106 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>"); 107 MODULE_DESCRIPTION("AD7879(-1) touchscreen I2C bus driver"); 108 MODULE_LICENSE("GPL"); 109