1 /*
2  * cyttsp_i2c_common.c
3  * Cypress TrueTouch(TM) Standard Product (TTSP) I2C touchscreen driver.
4  * For use with Cypress Txx3xx and Txx4xx parts.
5  * Supported parts include:
6  * CY8CTST341
7  * CY8CTMA340
8  * TMA4XX
9  * TMA1036
10  *
11  * Copyright (C) 2009, 2010, 2011 Cypress Semiconductor, Inc.
12  * Copyright (C) 2012 Javier Martinez Canillas <javier@dowhile0.org>
13  *
14  * This program is free software; you can redistribute it and/or
15  * modify it under the terms of the GNU General Public License
16  * version 2, and only version 2, as published by the
17  * Free Software Foundation.
18  *
19  * This program is distributed in the hope that it will be useful,
20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
22  * GNU General Public License for more details.
23  *
24  * Contact Cypress Semiconductor at www.cypress.com <ttdrivers@cypress.com>
25  *
26  */
27 
28 #include <linux/device.h>
29 #include <linux/export.h>
30 #include <linux/i2c.h>
31 #include <linux/module.h>
32 #include <linux/types.h>
33 
34 int cyttsp_i2c_read_block_data(struct device *dev, u8 *xfer_buf,
35 				      u8 addr, u8 length, void *values)
36 {
37 	struct i2c_client *client = to_i2c_client(dev);
38 	struct i2c_msg msgs[] = {
39 		{
40 			.addr = client->addr,
41 			.flags = 0,
42 			.len = 1,
43 			.buf = &addr,
44 		},
45 		{
46 			.addr = client->addr,
47 			.flags = I2C_M_RD,
48 			.len = length,
49 			.buf = values,
50 		},
51 	};
52 	int retval;
53 
54 	retval = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
55 	if (retval < 0)
56 		return retval;
57 
58 	return retval != ARRAY_SIZE(msgs) ? -EIO : 0;
59 }
60 EXPORT_SYMBOL_GPL(cyttsp_i2c_read_block_data);
61 
62 int cyttsp_i2c_write_block_data(struct device *dev, u8 *xfer_buf,
63 				       u8 addr, u8 length, const void *values)
64 {
65 	struct i2c_client *client = to_i2c_client(dev);
66 	int retval;
67 
68 	xfer_buf[0] = addr;
69 	memcpy(&xfer_buf[1], values, length);
70 
71 	retval = i2c_master_send(client, xfer_buf, length + 1);
72 
73 	return retval < 0 ? retval : 0;
74 }
75 EXPORT_SYMBOL_GPL(cyttsp_i2c_write_block_data);
76 
77 
78 MODULE_LICENSE("GPL");
79 MODULE_AUTHOR("Cypress");
80