1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * cyttsp_i2c.c
4 * Cypress TrueTouch(TM) Standard Product (TTSP) I2C touchscreen driver.
5 * For use with Cypress Txx3xx parts.
6 * Supported parts include:
7 * CY8CTST341
8 * CY8CTMA340
9 *
10 * Copyright (C) 2009, 2010, 2011 Cypress Semiconductor, Inc.
11 * Copyright (C) 2012 Javier Martinez Canillas <javier@dowhile0.org>
12 *
13 * Contact Cypress Semiconductor at www.cypress.com <ttdrivers@cypress.com>
14 */
15
16 #include "cyttsp_core.h"
17
18 #include <linux/i2c.h>
19 #include <linux/input.h>
20
21 #define CY_I2C_NAME "cyttsp-i2c"
22
23 #define CY_I2C_DATA_SIZE 128
24
cyttsp_i2c_read_block_data(struct device * dev,u8 * xfer_buf,u16 addr,u8 length,void * values)25 static int cyttsp_i2c_read_block_data(struct device *dev, u8 *xfer_buf,
26 u16 addr, u8 length, void *values)
27 {
28 struct i2c_client *client = to_i2c_client(dev);
29 u8 client_addr = client->addr | ((addr >> 8) & 0x1);
30 u8 addr_lo = addr & 0xFF;
31 struct i2c_msg msgs[] = {
32 {
33 .addr = client_addr,
34 .flags = 0,
35 .len = 1,
36 .buf = &addr_lo,
37 },
38 {
39 .addr = client_addr,
40 .flags = I2C_M_RD,
41 .len = length,
42 .buf = values,
43 },
44 };
45 int retval;
46
47 retval = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
48 if (retval < 0)
49 return retval;
50
51 return retval != ARRAY_SIZE(msgs) ? -EIO : 0;
52 }
53
cyttsp_i2c_write_block_data(struct device * dev,u8 * xfer_buf,u16 addr,u8 length,const void * values)54 static int cyttsp_i2c_write_block_data(struct device *dev, u8 *xfer_buf,
55 u16 addr, u8 length, const void *values)
56 {
57 struct i2c_client *client = to_i2c_client(dev);
58 u8 client_addr = client->addr | ((addr >> 8) & 0x1);
59 u8 addr_lo = addr & 0xFF;
60 struct i2c_msg msgs[] = {
61 {
62 .addr = client_addr,
63 .flags = 0,
64 .len = length + 1,
65 .buf = xfer_buf,
66 },
67 };
68 int retval;
69
70 xfer_buf[0] = addr_lo;
71 memcpy(&xfer_buf[1], values, length);
72
73 retval = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
74 if (retval < 0)
75 return retval;
76
77 return retval != ARRAY_SIZE(msgs) ? -EIO : 0;
78 }
79
80 static const struct cyttsp_bus_ops cyttsp_i2c_bus_ops = {
81 .bustype = BUS_I2C,
82 .write = cyttsp_i2c_write_block_data,
83 .read = cyttsp_i2c_read_block_data,
84 };
85
cyttsp_i2c_probe(struct i2c_client * client)86 static int cyttsp_i2c_probe(struct i2c_client *client)
87 {
88 struct cyttsp *ts;
89
90 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
91 dev_err(&client->dev, "I2C functionality not Supported\n");
92 return -EIO;
93 }
94
95 ts = cyttsp_probe(&cyttsp_i2c_bus_ops, &client->dev, client->irq,
96 CY_I2C_DATA_SIZE);
97
98 if (IS_ERR(ts))
99 return PTR_ERR(ts);
100
101 i2c_set_clientdata(client, ts);
102 return 0;
103 }
104
105 static const struct i2c_device_id cyttsp_i2c_id[] = {
106 { CY_I2C_NAME },
107 { }
108 };
109 MODULE_DEVICE_TABLE(i2c, cyttsp_i2c_id);
110
111 static const struct of_device_id cyttsp_of_i2c_match[] = {
112 { .compatible = "cypress,cy8ctma340", },
113 { .compatible = "cypress,cy8ctst341", },
114 { /* sentinel */ }
115 };
116 MODULE_DEVICE_TABLE(of, cyttsp_of_i2c_match);
117
118 static struct i2c_driver cyttsp_i2c_driver = {
119 .driver = {
120 .name = CY_I2C_NAME,
121 .pm = pm_sleep_ptr(&cyttsp_pm_ops),
122 .of_match_table = cyttsp_of_i2c_match,
123 },
124 .probe = cyttsp_i2c_probe,
125 .id_table = cyttsp_i2c_id,
126 };
127
128 module_i2c_driver(cyttsp_i2c_driver);
129
130 MODULE_LICENSE("GPL");
131 MODULE_DESCRIPTION("Cypress TrueTouch(R) Standard Product (TTSP) I2C driver");
132 MODULE_AUTHOR("Cypress");
133