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 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 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 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 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 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->no_extra_sync = 0; 77 78 handle->write_data = i2c_write_data; 79 handle->write_cmd = i2c_write_cmd; 80 handle->read_data = i2c_read_data; 81 handle->read_ack = i2c_read_ack; 82 83 if (ioctl(i2c_handle->fd, I2C_SLAVE, i2c_handle->addr) < 0) { 84 perror("Error setting slave addr"); 85 return -1; 86 } else { 87 return 0; 88 } 89 } 90
