[41c5f1b7] | 1 | /** |
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| 2 | * @file |
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| 3 | * |
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| 4 | * @brief Inter-Integrated Circuit (I2C) Bus Implementation |
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| 5 | * |
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| 6 | * @ingroup I2CDevice |
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| 7 | */ |
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| 8 | |
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| 9 | /* |
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| 10 | * Copyright (c) 2014 embedded brains GmbH. All rights reserved. |
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| 11 | * |
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| 12 | * embedded brains GmbH |
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| 13 | * Dornierstr. 4 |
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| 14 | * 82178 Puchheim |
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| 15 | * Germany |
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| 16 | * <rtems@embedded-brains.de> |
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| 17 | * |
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| 18 | * The license and distribution terms for this file may be |
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| 19 | * found in the file LICENSE in this distribution or at |
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| 20 | * http://www.rtems.org/license/LICENSE. |
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| 21 | */ |
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| 22 | |
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| 23 | #if HAVE_CONFIG_H |
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| 24 | #include "config.h" |
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| 25 | #endif |
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| 26 | |
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| 27 | #include <dev/i2c/i2c.h> |
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| 28 | |
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| 29 | #include <rtems/imfs.h> |
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| 30 | #include <rtems/score/assert.h> |
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| 31 | |
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| 32 | #include <fcntl.h> |
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| 33 | #include <stdlib.h> |
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| 34 | #include <unistd.h> |
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| 35 | |
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| 36 | static ssize_t i2c_dev_read( |
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| 37 | rtems_libio_t *iop, |
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| 38 | void *buffer, |
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| 39 | size_t count |
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| 40 | ) |
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| 41 | { |
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| 42 | i2c_dev *dev = IMFS_generic_get_context_by_iop(iop); |
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| 43 | ssize_t n; |
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| 44 | |
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| 45 | n = (*dev->read)(dev, buffer, count, iop->offset); |
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| 46 | if (n > 0) { |
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| 47 | iop->offset += n; |
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| 48 | } |
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| 49 | |
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| 50 | return n; |
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| 51 | } |
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| 52 | |
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| 53 | static ssize_t i2c_dev_write( |
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| 54 | rtems_libio_t *iop, |
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| 55 | const void *buffer, |
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| 56 | size_t count |
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| 57 | ) |
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| 58 | { |
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| 59 | i2c_dev *dev = IMFS_generic_get_context_by_iop(iop); |
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| 60 | ssize_t n; |
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| 61 | |
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| 62 | n = (*dev->write)(dev, buffer, count, iop->offset); |
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| 63 | if (n > 0) { |
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| 64 | iop->offset += n; |
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| 65 | } |
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| 66 | |
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| 67 | return n; |
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| 68 | } |
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| 69 | |
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| 70 | static int i2c_dev_ioctl( |
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| 71 | rtems_libio_t *iop, |
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| 72 | ioctl_command_t command, |
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| 73 | void *arg |
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| 74 | ) |
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| 75 | { |
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| 76 | i2c_dev *dev = IMFS_generic_get_context_by_iop(iop); |
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| 77 | int err; |
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| 78 | |
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| 79 | err = (*dev->ioctl)(dev, command, arg); |
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| 80 | |
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| 81 | if (err == 0) { |
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| 82 | return 0; |
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| 83 | } else { |
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| 84 | rtems_set_errno_and_return_minus_one(-err); |
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| 85 | } |
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| 86 | } |
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| 87 | |
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| 88 | static int i2c_dev_fstat( |
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| 89 | const rtems_filesystem_location_info_t *loc, |
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| 90 | struct stat *buf |
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| 91 | ) |
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| 92 | { |
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| 93 | i2c_dev *dev = IMFS_generic_get_context_by_location(loc); |
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| 94 | |
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| 95 | buf->st_size = (*dev->get_size)(dev); |
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| 96 | buf->st_blksize = (*dev->get_block_size)(dev); |
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| 97 | |
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| 98 | return IMFS_stat(loc, buf); |
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| 99 | } |
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| 100 | |
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| 101 | static const rtems_filesystem_file_handlers_r i2c_dev_handler = { |
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| 102 | .open_h = rtems_filesystem_default_open, |
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| 103 | .close_h = rtems_filesystem_default_close, |
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| 104 | .read_h = i2c_dev_read, |
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| 105 | .write_h = i2c_dev_write, |
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| 106 | .ioctl_h = i2c_dev_ioctl, |
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| 107 | .lseek_h = rtems_filesystem_default_lseek_file, |
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| 108 | .fstat_h = i2c_dev_fstat, |
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| 109 | .ftruncate_h = rtems_filesystem_default_ftruncate, |
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| 110 | .fsync_h = rtems_filesystem_default_fsync_or_fdatasync, |
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| 111 | .fdatasync_h = rtems_filesystem_default_fsync_or_fdatasync, |
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| 112 | .fcntl_h = rtems_filesystem_default_fcntl, |
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| 113 | .kqfilter_h = rtems_filesystem_default_kqfilter, |
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| 114 | .poll_h = rtems_filesystem_default_poll, |
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| 115 | .readv_h = rtems_filesystem_default_readv, |
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| 116 | .writev_h = rtems_filesystem_default_writev |
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| 117 | }; |
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| 118 | |
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[cf36b70] | 119 | static void i2c_dev_node_destroy(IMFS_jnode_t *node) |
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[41c5f1b7] | 120 | { |
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| 121 | i2c_dev *dev; |
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| 122 | |
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| 123 | dev = IMFS_generic_get_context_by_node(node); |
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| 124 | (*dev->destroy)(dev); |
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| 125 | |
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[cf36b70] | 126 | IMFS_node_destroy_default(node); |
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[41c5f1b7] | 127 | } |
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| 128 | |
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[cf36b70] | 129 | static const IMFS_node_control i2c_dev_node_control = IMFS_GENERIC_INITIALIZER( |
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| 130 | &i2c_dev_handler, |
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| 131 | IMFS_node_initialize_generic, |
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| 132 | i2c_dev_node_destroy |
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| 133 | ); |
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[41c5f1b7] | 134 | |
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| 135 | int i2c_dev_register( |
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| 136 | i2c_dev *dev, |
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| 137 | const char *dev_path |
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| 138 | ) |
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| 139 | { |
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| 140 | int rv; |
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| 141 | |
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| 142 | rv = IMFS_make_generic_node( |
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| 143 | dev_path, |
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| 144 | S_IFCHR | S_IRWXU | S_IRWXG | S_IRWXO, |
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| 145 | &i2c_dev_node_control, |
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| 146 | dev |
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| 147 | ); |
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| 148 | if (rv != 0) { |
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| 149 | (*dev->destroy)(dev); |
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| 150 | } |
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| 151 | |
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| 152 | return rv; |
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| 153 | } |
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| 154 | |
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| 155 | static ssize_t i2c_dev_read_default( |
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| 156 | i2c_dev *dev, |
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| 157 | void *buf, |
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| 158 | size_t n, |
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| 159 | off_t offset |
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| 160 | ) |
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| 161 | { |
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| 162 | (void) dev; |
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| 163 | (void) buf; |
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| 164 | (void) n; |
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| 165 | (void) offset; |
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| 166 | |
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| 167 | return -EIO; |
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| 168 | } |
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| 169 | |
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| 170 | static ssize_t i2c_dev_write_default( |
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| 171 | i2c_dev *dev, |
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| 172 | const void *buf, |
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| 173 | size_t n, |
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| 174 | off_t offset |
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| 175 | ) |
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| 176 | { |
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| 177 | (void) dev; |
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| 178 | (void) buf; |
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| 179 | (void) n; |
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| 180 | (void) offset; |
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| 181 | |
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| 182 | return -EIO; |
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| 183 | } |
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| 184 | |
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| 185 | static int i2c_dev_ioctl_default( |
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| 186 | i2c_dev *dev, |
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| 187 | ioctl_command_t command, |
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| 188 | void *arg |
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| 189 | ) |
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| 190 | { |
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| 191 | (void) dev; |
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| 192 | (void) command; |
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| 193 | (void) arg; |
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| 194 | |
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| 195 | return -ENOTTY; |
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| 196 | } |
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| 197 | |
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| 198 | static off_t i2c_dev_get_size_default(i2c_dev *dev) |
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| 199 | { |
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| 200 | (void) dev; |
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| 201 | |
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| 202 | return 0; |
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| 203 | } |
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| 204 | |
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| 205 | static blksize_t i2c_dev_get_block_size_default(i2c_dev *dev) |
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| 206 | { |
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| 207 | (void) dev; |
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| 208 | |
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| 209 | return 1; |
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| 210 | } |
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| 211 | |
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| 212 | static int i2c_dev_do_init( |
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| 213 | i2c_dev *dev, |
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| 214 | const char *bus_path, |
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| 215 | uint16_t address, |
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| 216 | void (*destroy)(i2c_dev *dev) |
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| 217 | ) |
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| 218 | { |
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| 219 | int rv; |
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| 220 | |
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[90b0e28] | 221 | dev->bus_fd = open(bus_path, O_RDWR); |
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| 222 | if (dev->bus_fd < 0) { |
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[41c5f1b7] | 223 | (*destroy)(dev); |
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[90b0e28] | 224 | |
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[41c5f1b7] | 225 | return -1; |
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| 226 | } |
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| 227 | |
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[90b0e28] | 228 | rv = ioctl(dev->bus_fd, I2C_BUS_GET_CONTROL, &dev->bus); |
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[41c5f1b7] | 229 | if (rv != 0) { |
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| 230 | (*destroy)(dev); |
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[90b0e28] | 231 | |
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[41c5f1b7] | 232 | return -1; |
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| 233 | } |
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| 234 | |
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| 235 | dev->read = i2c_dev_read_default; |
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| 236 | dev->write = i2c_dev_write_default; |
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| 237 | dev->ioctl = i2c_dev_ioctl_default; |
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| 238 | dev->get_size = i2c_dev_get_size_default; |
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| 239 | dev->get_block_size = i2c_dev_get_block_size_default; |
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| 240 | dev->destroy = destroy; |
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| 241 | dev->address = address; |
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| 242 | |
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| 243 | return 0; |
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| 244 | } |
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| 245 | |
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| 246 | void i2c_dev_destroy(i2c_dev *dev) |
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| 247 | { |
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| 248 | int rv; |
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| 249 | |
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| 250 | rv = close(dev->bus_fd); |
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[90b0e28] | 251 | _Assert(dev->bus_fd < 0 || rv == 0); |
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[41c5f1b7] | 252 | (void) rv; |
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| 253 | } |
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| 254 | |
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| 255 | void i2c_dev_destroy_and_free(i2c_dev *dev) |
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| 256 | { |
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| 257 | i2c_dev_destroy(dev); |
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| 258 | free(dev); |
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| 259 | } |
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| 260 | |
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| 261 | int i2c_dev_init(i2c_dev *dev, const char *bus_path, uint16_t address) |
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| 262 | { |
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| 263 | return i2c_dev_do_init(dev, bus_path, address, i2c_dev_destroy); |
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| 264 | } |
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| 265 | |
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| 266 | i2c_dev *i2c_dev_alloc_and_init( |
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| 267 | size_t size, |
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| 268 | const char *bus_path, |
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| 269 | uint16_t address |
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| 270 | ) |
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| 271 | { |
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| 272 | i2c_dev *dev = NULL; |
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| 273 | |
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| 274 | if (size >= sizeof(*dev)) { |
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| 275 | dev = calloc(1, size); |
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| 276 | if (dev != NULL) { |
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| 277 | int rv; |
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| 278 | |
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| 279 | rv = i2c_dev_do_init(dev, bus_path, address, i2c_dev_destroy_and_free); |
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| 280 | if (rv != 0) { |
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| 281 | return NULL; |
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| 282 | } |
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| 283 | } |
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| 284 | } |
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| 285 | |
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| 286 | return dev; |
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| 287 | } |
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