1 /*
2 * Copyright (C) 2015 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include <stdio.h>
18 #include <stdint.h>
19 #include <unistd.h>
20 #include <sys/ioctl.h>
21 #include <linux/i2c-dev.h>
22
23 #include "stm32_bl.h"
24 #include "i2c.h"
25
i2c_write_data(handle_t * handle,uint8_t * buffer,int length)26 uint8_t i2c_write_data(handle_t *handle, uint8_t *buffer, int length)
27 {
28 i2c_handle_t *i2c_handle = (i2c_handle_t *)handle;
29
30 buffer[length] = checksum(handle, buffer, length);
31
32 if (write(i2c_handle->fd, buffer, length+1) == (length+1))
33 return CMD_ACK;
34 else
35 return CMD_NACK;
36 }
37
i2c_write_cmd(handle_t * handle,uint8_t cmd)38 uint8_t i2c_write_cmd(handle_t *handle, uint8_t cmd)
39 {
40 uint8_t buffer[sizeof(uint8_t)+1] =
41 {
42 cmd
43 };
44
45 return handle->write_data(handle, buffer, sizeof(uint8_t));
46 }
47
i2c_read_data(handle_t * handle,uint8_t * data,int length)48 uint8_t i2c_read_data(handle_t *handle, uint8_t *data, int length)
49 {
50 i2c_handle_t *i2c_handle = (i2c_handle_t *)handle;
51
52 if (read(i2c_handle->fd, data, length) == length)
53 return CMD_ACK;
54 else
55 return CMD_NACK;
56 }
57
i2c_read_ack(handle_t * handle)58 uint8_t i2c_read_ack(handle_t *handle)
59 {
60 uint8_t buffer;
61
62 if (handle->read_data(handle, &buffer, sizeof(uint8_t)) == CMD_ACK)
63 return buffer;
64 else
65 return CMD_NACK;
66 }
67
i2c_init(handle_t * handle)68 int i2c_init(handle_t *handle)
69 {
70 i2c_handle_t *i2c_handle = (i2c_handle_t *)handle;
71
72 handle->cmd_erase = CMD_ERASE_NS;
73 handle->cmd_read_memory = CMD_READ_MEMORY;
74 handle->cmd_write_memory = CMD_WRITE_MEMORY_NS;
75
76 handle->write_data = i2c_write_data;
77 handle->write_cmd = i2c_write_cmd;
78 handle->read_data = i2c_read_data;
79 handle->read_ack = i2c_read_ack;
80
81 if (ioctl(i2c_handle->fd, I2C_SLAVE, i2c_handle->addr) < 0) {
82 perror("Error setting slave addr");
83 return -1;
84 } else {
85 return 0;
86 }
87 }
88