1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * cyttsp_i2c_common.c
4  * Cypress TrueTouch(TM) Standard Product (TTSP) I2C touchscreen driver.
5  * For use with Cypress Txx3xx and Txx4xx parts.
6  * Supported parts include:
7  * CY8CTST341
8  * CY8CTMA340
9  * TMA4XX
10  * TMA1036
11  *
12  * Copyright (C) 2009, 2010, 2011 Cypress Semiconductor, Inc.
13  * Copyright (C) 2012 Javier Martinez Canillas <javier@dowhile0.org>
14  *
15  * Contact Cypress Semiconductor at www.cypress.com <ttdrivers@cypress.com>
16  */
17 
18 #include <linux/device.h>
19 #include <linux/export.h>
20 #include <linux/i2c.h>
21 #include <linux/module.h>
22 #include <linux/types.h>
23 
24 #include "cyttsp4_core.h"
25 
26 int cyttsp_i2c_read_block_data(struct device *dev, u8 *xfer_buf,
27 				      u16 addr, u8 length, void *values)
28 {
29 	struct i2c_client *client = to_i2c_client(dev);
30 	u8 client_addr = client->addr | ((addr >> 8) & 0x1);
31 	u8 addr_lo = addr & 0xFF;
32 	struct i2c_msg msgs[] = {
33 		{
34 			.addr = client_addr,
35 			.flags = 0,
36 			.len = 1,
37 			.buf = &addr_lo,
38 		},
39 		{
40 			.addr = client_addr,
41 			.flags = I2C_M_RD,
42 			.len = length,
43 			.buf = values,
44 		},
45 	};
46 	int retval;
47 
48 	retval = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
49 	if (retval < 0)
50 		return retval;
51 
52 	return retval != ARRAY_SIZE(msgs) ? -EIO : 0;
53 }
54 EXPORT_SYMBOL_GPL(cyttsp_i2c_read_block_data);
55 
56 int cyttsp_i2c_write_block_data(struct device *dev, u8 *xfer_buf,
57 				       u16 addr, u8 length, const void *values)
58 {
59 	struct i2c_client *client = to_i2c_client(dev);
60 	u8 client_addr = client->addr | ((addr >> 8) & 0x1);
61 	u8 addr_lo = addr & 0xFF;
62 	struct i2c_msg msgs[] = {
63 		{
64 			.addr = client_addr,
65 			.flags = 0,
66 			.len = length + 1,
67 			.buf = xfer_buf,
68 		},
69 	};
70 	int retval;
71 
72 	xfer_buf[0] = addr_lo;
73 	memcpy(&xfer_buf[1], values, length);
74 
75 	retval = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
76 	if (retval < 0)
77 		return retval;
78 
79 	return retval != ARRAY_SIZE(msgs) ? -EIO : 0;
80 }
81 EXPORT_SYMBOL_GPL(cyttsp_i2c_write_block_data);
82 
83 
84 MODULE_LICENSE("GPL");
85 MODULE_AUTHOR("Cypress");
86