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 				      u16 addr, u8 length, void *values)
36 {
37 	struct i2c_client *client = to_i2c_client(dev);
38 	u8 client_addr = client->addr | ((addr >> 8) & 0x1);
39 	u8 addr_lo = addr & 0xFF;
40 	struct i2c_msg msgs[] = {
41 		{
42 			.addr = client_addr,
43 			.flags = 0,
44 			.len = 1,
45 			.buf = &addr_lo,
46 		},
47 		{
48 			.addr = client_addr,
49 			.flags = I2C_M_RD,
50 			.len = length,
51 			.buf = values,
52 		},
53 	};
54 	int retval;
55 
56 	retval = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
57 	if (retval < 0)
58 		return retval;
59 
60 	return retval != ARRAY_SIZE(msgs) ? -EIO : 0;
61 }
62 EXPORT_SYMBOL_GPL(cyttsp_i2c_read_block_data);
63 
64 int cyttsp_i2c_write_block_data(struct device *dev, u8 *xfer_buf,
65 				       u16 addr, u8 length, const void *values)
66 {
67 	struct i2c_client *client = to_i2c_client(dev);
68 	u8 client_addr = client->addr | ((addr >> 8) & 0x1);
69 	u8 addr_lo = addr & 0xFF;
70 	struct i2c_msg msgs[] = {
71 		{
72 			.addr = client_addr,
73 			.flags = 0,
74 			.len = length + 1,
75 			.buf = xfer_buf,
76 		},
77 	};
78 	int retval;
79 
80 	xfer_buf[0] = addr_lo;
81 	memcpy(&xfer_buf[1], values, length);
82 
83 	retval = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
84 	if (retval < 0)
85 		return retval;
86 
87 	return retval != ARRAY_SIZE(msgs) ? -EIO : 0;
88 }
89 EXPORT_SYMBOL_GPL(cyttsp_i2c_write_block_data);
90 
91 
92 MODULE_LICENSE("GPL");
93 MODULE_AUTHOR("Cypress");
94