14397c98aSMike Frysinger /* 24397c98aSMike Frysinger * AD7879-1/AD7889-1 touchscreen (I2C bus) 34397c98aSMike Frysinger * 44397c98aSMike Frysinger * Copyright (C) 2008-2010 Michael Hennerich, Analog Devices Inc. 54397c98aSMike Frysinger * 64397c98aSMike Frysinger * Licensed under the GPL-2 or later. 74397c98aSMike Frysinger */ 84397c98aSMike Frysinger 94397c98aSMike Frysinger #include <linux/input.h> /* BUS_I2C */ 104397c98aSMike Frysinger #include <linux/i2c.h> 114397c98aSMike Frysinger #include <linux/module.h> 124397c98aSMike Frysinger #include <linux/types.h> 13d5dc9ac3SMark Brown #include <linux/pm.h> 144397c98aSMike Frysinger 154397c98aSMike Frysinger #include "ad7879.h" 164397c98aSMike Frysinger 174397c98aSMike Frysinger #define AD7879_DEVID 0x79 /* AD7879-1/AD7889-1 */ 184397c98aSMike Frysinger 194397c98aSMike Frysinger /* All registers are word-sized. 204397c98aSMike Frysinger * AD7879 uses a high-byte first convention. 214397c98aSMike Frysinger */ 224397c98aSMike Frysinger static int ad7879_i2c_read(struct device *dev, u8 reg) 234397c98aSMike Frysinger { 244397c98aSMike Frysinger struct i2c_client *client = to_i2c_client(dev); 254397c98aSMike Frysinger 264397c98aSMike Frysinger return swab16(i2c_smbus_read_word_data(client, reg)); 274397c98aSMike Frysinger } 284397c98aSMike Frysinger 294397c98aSMike Frysinger static int ad7879_i2c_multi_read(struct device *dev, 304397c98aSMike Frysinger u8 first_reg, u8 count, u16 *buf) 314397c98aSMike Frysinger { 3216ea10a7SMichael Hennerich struct i2c_client *client = to_i2c_client(dev); 334397c98aSMike Frysinger u8 idx; 344397c98aSMike Frysinger 3516ea10a7SMichael Hennerich i2c_smbus_read_i2c_block_data(client, first_reg, count * 2, (u8 *)buf); 3616ea10a7SMichael Hennerich 374397c98aSMike Frysinger for (idx = 0; idx < count; ++idx) 3816ea10a7SMichael Hennerich buf[idx] = swab16(buf[idx]); 394397c98aSMike Frysinger 404397c98aSMike Frysinger return 0; 414397c98aSMike Frysinger } 424397c98aSMike Frysinger 434397c98aSMike Frysinger static int ad7879_i2c_write(struct device *dev, u8 reg, u16 val) 444397c98aSMike Frysinger { 454397c98aSMike Frysinger struct i2c_client *client = to_i2c_client(dev); 464397c98aSMike Frysinger 474397c98aSMike Frysinger return i2c_smbus_write_word_data(client, reg, swab16(val)); 484397c98aSMike Frysinger } 494397c98aSMike Frysinger 504397c98aSMike Frysinger static const struct ad7879_bus_ops ad7879_i2c_bus_ops = { 514397c98aSMike Frysinger .bustype = BUS_I2C, 524397c98aSMike Frysinger .read = ad7879_i2c_read, 534397c98aSMike Frysinger .multi_read = ad7879_i2c_multi_read, 544397c98aSMike Frysinger .write = ad7879_i2c_write, 554397c98aSMike Frysinger }; 564397c98aSMike Frysinger 574397c98aSMike Frysinger static int __devinit ad7879_i2c_probe(struct i2c_client *client, 584397c98aSMike Frysinger const struct i2c_device_id *id) 594397c98aSMike Frysinger { 604397c98aSMike Frysinger struct ad7879 *ts; 614397c98aSMike Frysinger 624397c98aSMike Frysinger if (!i2c_check_functionality(client->adapter, 634397c98aSMike Frysinger I2C_FUNC_SMBUS_WORD_DATA)) { 644397c98aSMike Frysinger dev_err(&client->dev, "SMBUS Word Data not Supported\n"); 654397c98aSMike Frysinger return -EIO; 664397c98aSMike Frysinger } 674397c98aSMike Frysinger 684397c98aSMike Frysinger ts = ad7879_probe(&client->dev, AD7879_DEVID, client->irq, 694397c98aSMike Frysinger &ad7879_i2c_bus_ops); 704397c98aSMike Frysinger if (IS_ERR(ts)) 714397c98aSMike Frysinger return PTR_ERR(ts); 724397c98aSMike Frysinger 734397c98aSMike Frysinger i2c_set_clientdata(client, ts); 744397c98aSMike Frysinger 754397c98aSMike Frysinger return 0; 764397c98aSMike Frysinger } 774397c98aSMike Frysinger 784397c98aSMike Frysinger static int __devexit ad7879_i2c_remove(struct i2c_client *client) 794397c98aSMike Frysinger { 804397c98aSMike Frysinger struct ad7879 *ts = i2c_get_clientdata(client); 814397c98aSMike Frysinger 824397c98aSMike Frysinger ad7879_remove(ts); 834397c98aSMike Frysinger 844397c98aSMike Frysinger return 0; 854397c98aSMike Frysinger } 864397c98aSMike Frysinger 874397c98aSMike Frysinger static const struct i2c_device_id ad7879_id[] = { 884397c98aSMike Frysinger { "ad7879", 0 }, 894397c98aSMike Frysinger { "ad7889", 0 }, 904397c98aSMike Frysinger { } 914397c98aSMike Frysinger }; 924397c98aSMike Frysinger MODULE_DEVICE_TABLE(i2c, ad7879_id); 934397c98aSMike Frysinger 944397c98aSMike Frysinger static struct i2c_driver ad7879_i2c_driver = { 954397c98aSMike Frysinger .driver = { 964397c98aSMike Frysinger .name = "ad7879", 974397c98aSMike Frysinger .owner = THIS_MODULE, 988672bd93SDmitry Torokhov .pm = &ad7879_pm_ops, 994397c98aSMike Frysinger }, 1004397c98aSMike Frysinger .probe = ad7879_i2c_probe, 1014397c98aSMike Frysinger .remove = __devexit_p(ad7879_i2c_remove), 1024397c98aSMike Frysinger .id_table = ad7879_id, 1034397c98aSMike Frysinger }; 1044397c98aSMike Frysinger 1054397c98aSMike Frysinger static int __init ad7879_i2c_init(void) 1064397c98aSMike Frysinger { 1074397c98aSMike Frysinger return i2c_add_driver(&ad7879_i2c_driver); 1084397c98aSMike Frysinger } 1094397c98aSMike Frysinger module_init(ad7879_i2c_init); 1104397c98aSMike Frysinger 1114397c98aSMike Frysinger static void __exit ad7879_i2c_exit(void) 1124397c98aSMike Frysinger { 1134397c98aSMike Frysinger i2c_del_driver(&ad7879_i2c_driver); 1144397c98aSMike Frysinger } 1154397c98aSMike Frysinger module_exit(ad7879_i2c_exit); 1164397c98aSMike Frysinger 1174397c98aSMike Frysinger MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>"); 1184397c98aSMike Frysinger MODULE_DESCRIPTION("AD7879(-1) touchscreen I2C bus driver"); 1194397c98aSMike Frysinger MODULE_LICENSE("GPL"); 1204397c98aSMike Frysinger MODULE_ALIAS("i2c:ad7879"); 121