1 /*
2 *
3 * FocalTech TouchScreen driver.
4 *
5 * Copyright (c) 2012-2019, FocalTech Systems, Ltd., all rights reserved.
6 *
7 * This software is licensed under the terms of the GNU General Public
8 * License version 2, as published by the Free Software Foundation, and
9 * may be copied, distributed, and modified under those terms.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 */
17
18 /************************************************************************
19 *
20 * File Name: focaltech_i2c.c
21 *
22 * Author: Focaltech Driver Team
23 *
24 * Created: 2016-08-04
25 *
26 * Abstract: i2c communication with TP
27 *
28 * Version: v1.0
29 *
30 * Revision History:
31 *
32 ************************************************************************/
33
34 /*****************************************************************************
35 * Included header files
36 *****************************************************************************/
37 #include "focaltech_core.h"
38
39 /*****************************************************************************
40 * Private constant and macro definitions using #define
41 *****************************************************************************/
42 #define I2C_RETRY_NUMBER 3
43 #define I2C_BUF_LENGTH 256
44
45 /*****************************************************************************
46 * Private enumerations, structures and unions using typedef
47 *****************************************************************************/
48
49 /*****************************************************************************
50 * Static variables
51 *****************************************************************************/
52
53 /*****************************************************************************
54 * Global variable or extern global variabls/functions
55 *****************************************************************************/
56
57 /*****************************************************************************
58 * Static function prototypes
59 *****************************************************************************/
60
61 /*****************************************************************************
62 * functions body
63 *****************************************************************************/
fts_read(u8 * cmd,u32 cmdlen,u8 * data,u32 datalen)64 int fts_read(u8 *cmd, u32 cmdlen, u8 *data, u32 datalen)
65 {
66 int ret = 0;
67 int i = 0;
68 struct fts_ts_data *ts_data = fts_data;
69 struct i2c_msg msg_list[2];
70 struct i2c_msg *msg = NULL;
71 int msg_num = 0;
72
73 /* must have data when read */
74 if (!ts_data || !ts_data->client || !data || !datalen
75 || (datalen >= I2C_BUF_LENGTH) || (cmdlen >= I2C_BUF_LENGTH)) {
76 FTS_ERROR("fts_data/client/cmdlen(%d)/data/datalen(%d) is invalid",
77 cmdlen, datalen);
78 return -EINVAL;
79 }
80
81 mutex_lock(&ts_data->bus_lock);
82 memset(&msg_list[0], 0, sizeof(struct i2c_msg));
83 memset(&msg_list[1], 0, sizeof(struct i2c_msg));
84 memcpy(ts_data->bus_tx_buf, cmd, cmdlen);
85 msg_list[0].addr = ts_data->client->addr;
86 msg_list[0].flags = 0;
87 msg_list[0].len = cmdlen;
88 msg_list[0].buf = ts_data->bus_tx_buf;
89 msg_list[1].addr = ts_data->client->addr;
90 msg_list[1].flags = I2C_M_RD;
91 msg_list[1].len = datalen;
92 msg_list[1].buf = ts_data->bus_rx_buf;
93 if (cmd && cmdlen) {
94 msg = &msg_list[0];
95 msg_num = 2;
96 } else {
97 msg = &msg_list[1];
98 msg_num = 1;
99 }
100
101 for (i = 0; i < I2C_RETRY_NUMBER; i++) {
102 ret = i2c_transfer(ts_data->client->adapter, msg, msg_num);
103 if (ret < 0) {
104 FTS_ERROR("i2c_transfer(read) fail,ret:%d", ret);
105 } else {
106 memcpy(data, ts_data->bus_rx_buf, datalen);
107 break;
108 }
109 }
110
111 mutex_unlock(&ts_data->bus_lock);
112 return ret;
113 }
114
fts_write(u8 * writebuf,u32 writelen)115 int fts_write(u8 *writebuf, u32 writelen)
116 {
117 int ret = 0;
118 int i = 0;
119 struct fts_ts_data *ts_data = fts_data;
120 struct i2c_msg msgs;
121
122 if (!ts_data || !ts_data->client || !writebuf || !writelen
123 || (writelen >= I2C_BUF_LENGTH)) {
124 FTS_ERROR("fts_data/client/data/datalen(%d) is invalid", writelen);
125 return -EINVAL;
126 }
127
128 mutex_lock(&ts_data->bus_lock);
129 memset(&msgs, 0, sizeof(struct i2c_msg));
130 memcpy(ts_data->bus_tx_buf, writebuf, writelen);
131 msgs.addr = ts_data->client->addr;
132 msgs.flags = 0;
133 msgs.len = writelen;
134 msgs.buf = ts_data->bus_tx_buf;
135 for (i = 0; i < I2C_RETRY_NUMBER; i++) {
136 ret = i2c_transfer(ts_data->client->adapter, &msgs, 1);
137 if (ret < 0) {
138 FTS_ERROR("i2c_transfer(write) fail,ret:%d", ret);
139 } else {
140 break;
141 }
142 }
143 mutex_unlock(&ts_data->bus_lock);
144 return ret;
145 }
146
fts_read_reg(u8 addr,u8 * value)147 int fts_read_reg(u8 addr, u8 *value)
148 {
149 return fts_read(&addr, 1, value, 1);
150 }
151
fts_write_reg(u8 addr,u8 value)152 int fts_write_reg(u8 addr, u8 value)
153 {
154 u8 buf[2] = { 0 };
155
156 buf[0] = addr;
157 buf[1] = value;
158 return fts_write(buf, sizeof(buf));
159 }
160
fts_bus_init(struct fts_ts_data * ts_data)161 int fts_bus_init(struct fts_ts_data *ts_data)
162 {
163 FTS_FUNC_ENTER();
164 ts_data->bus_tx_buf = kzalloc(I2C_BUF_LENGTH, GFP_KERNEL);
165 if (NULL == ts_data->bus_tx_buf) {
166 FTS_ERROR("failed to allocate memory for bus_tx_buf");
167 return -ENOMEM;
168 }
169
170 ts_data->bus_rx_buf = kzalloc(I2C_BUF_LENGTH, GFP_KERNEL);
171 if (NULL == ts_data->bus_rx_buf) {
172 FTS_ERROR("failed to allocate memory for bus_rx_buf");
173 return -ENOMEM;
174 }
175 FTS_FUNC_EXIT();
176 return 0;
177 }
178
fts_bus_exit(struct fts_ts_data * ts_data)179 int fts_bus_exit(struct fts_ts_data *ts_data)
180 {
181 FTS_FUNC_ENTER();
182 if (ts_data && ts_data->bus_tx_buf) {
183 kfree(ts_data->bus_tx_buf);
184 ts_data->bus_tx_buf = NULL;
185 }
186
187 if (ts_data && ts_data->bus_rx_buf) {
188 kfree(ts_data->bus_rx_buf);
189 ts_data->bus_rx_buf = NULL;
190 }
191 FTS_FUNC_EXIT();
192 return 0;
193 }