1 2 /* The industrial I/O core 3 * 4 * Copyright (c) 2008 Jonathan Cameron 5 * 6 * This program is free software; you can redistribute it and/or modify it 7 * under the terms of the GNU General Public License version 2 as published by 8 * the Free Software Foundation. 9 */ 10 #ifndef _INDUSTRIAL_IO_H_ 11 #define _INDUSTRIAL_IO_H_ 12 13 #include <linux/device.h> 14 #include <linux/cdev.h> 15 #include <linux/iio/types.h> 16 /* IIO TODO LIST */ 17 /* 18 * Provide means of adjusting timer accuracy. 19 * Currently assumes nano seconds. 20 */ 21 22 enum iio_chan_info_enum { 23 IIO_CHAN_INFO_RAW = 0, 24 IIO_CHAN_INFO_PROCESSED, 25 IIO_CHAN_INFO_SCALE, 26 IIO_CHAN_INFO_OFFSET, 27 IIO_CHAN_INFO_CALIBSCALE, 28 IIO_CHAN_INFO_CALIBBIAS, 29 IIO_CHAN_INFO_PEAK, 30 IIO_CHAN_INFO_PEAK_SCALE, 31 IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW, 32 IIO_CHAN_INFO_AVERAGE_RAW, 33 IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY, 34 IIO_CHAN_INFO_SAMP_FREQ, 35 IIO_CHAN_INFO_FREQUENCY, 36 IIO_CHAN_INFO_PHASE, 37 IIO_CHAN_INFO_HARDWAREGAIN, 38 }; 39 40 #define IIO_CHAN_INFO_SHARED_BIT(type) BIT(type*2) 41 #define IIO_CHAN_INFO_SEPARATE_BIT(type) BIT(type*2 + 1) 42 43 #define IIO_CHAN_INFO_RAW_SEPARATE_BIT \ 44 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_RAW) 45 #define IIO_CHAN_INFO_PROCESSED_SEPARATE_BIT \ 46 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_PROCESSED) 47 #define IIO_CHAN_INFO_SCALE_SEPARATE_BIT \ 48 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_SCALE) 49 #define IIO_CHAN_INFO_SCALE_SHARED_BIT \ 50 IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_SCALE) 51 #define IIO_CHAN_INFO_OFFSET_SEPARATE_BIT \ 52 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_OFFSET) 53 #define IIO_CHAN_INFO_OFFSET_SHARED_BIT \ 54 IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_OFFSET) 55 #define IIO_CHAN_INFO_CALIBSCALE_SEPARATE_BIT \ 56 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_CALIBSCALE) 57 #define IIO_CHAN_INFO_CALIBSCALE_SHARED_BIT \ 58 IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_CALIBSCALE) 59 #define IIO_CHAN_INFO_CALIBBIAS_SEPARATE_BIT \ 60 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_CALIBBIAS) 61 #define IIO_CHAN_INFO_CALIBBIAS_SHARED_BIT \ 62 IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_CALIBBIAS) 63 #define IIO_CHAN_INFO_PEAK_SEPARATE_BIT \ 64 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_PEAK) 65 #define IIO_CHAN_INFO_PEAK_SHARED_BIT \ 66 IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_PEAK) 67 #define IIO_CHAN_INFO_PEAKSCALE_SEPARATE_BIT \ 68 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_PEAKSCALE) 69 #define IIO_CHAN_INFO_PEAKSCALE_SHARED_BIT \ 70 IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_PEAKSCALE) 71 #define IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW_SEPARATE_BIT \ 72 IIO_CHAN_INFO_SEPARATE_BIT( \ 73 IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW) 74 #define IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW_SHARED_BIT \ 75 IIO_CHAN_INFO_SHARED_BIT( \ 76 IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW) 77 #define IIO_CHAN_INFO_AVERAGE_RAW_SEPARATE_BIT \ 78 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_AVERAGE_RAW) 79 #define IIO_CHAN_INFO_AVERAGE_RAW_SHARED_BIT \ 80 IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_AVERAGE_RAW) 81 #define IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY_SHARED_BIT \ 82 IIO_CHAN_INFO_SHARED_BIT( \ 83 IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY) 84 #define IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY_SEPARATE_BIT \ 85 IIO_CHAN_INFO_SEPARATE_BIT( \ 86 IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY) 87 #define IIO_CHAN_INFO_SAMP_FREQ_SEPARATE_BIT \ 88 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_SAMP_FREQ) 89 #define IIO_CHAN_INFO_SAMP_FREQ_SHARED_BIT \ 90 IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_SAMP_FREQ) 91 #define IIO_CHAN_INFO_FREQUENCY_SEPARATE_BIT \ 92 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_FREQUENCY) 93 #define IIO_CHAN_INFO_FREQUENCY_SHARED_BIT \ 94 IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_FREQUENCY) 95 #define IIO_CHAN_INFO_PHASE_SEPARATE_BIT \ 96 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_PHASE) 97 #define IIO_CHAN_INFO_PHASE_SHARED_BIT \ 98 IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_PHASE) 99 #define IIO_CHAN_INFO_HARDWAREGAIN_SEPARATE_BIT \ 100 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_HARDWAREGAIN) 101 #define IIO_CHAN_INFO_HARDWAREGAIN_SHARED_BIT \ 102 IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_HARDWAREGAIN) 103 104 enum iio_endian { 105 IIO_CPU, 106 IIO_BE, 107 IIO_LE, 108 }; 109 110 struct iio_chan_spec; 111 struct iio_dev; 112 113 /** 114 * struct iio_chan_spec_ext_info - Extended channel info attribute 115 * @name: Info attribute name 116 * @shared: Whether this attribute is shared between all channels. 117 * @read: Read callback for this info attribute, may be NULL. 118 * @write: Write callback for this info attribute, may be NULL. 119 * @private: Data private to the driver. 120 */ 121 struct iio_chan_spec_ext_info { 122 const char *name; 123 bool shared; 124 ssize_t (*read)(struct iio_dev *, uintptr_t private, 125 struct iio_chan_spec const *, char *buf); 126 ssize_t (*write)(struct iio_dev *, uintptr_t private, 127 struct iio_chan_spec const *, const char *buf, 128 size_t len); 129 uintptr_t private; 130 }; 131 132 /** 133 * struct iio_chan_spec - specification of a single channel 134 * @type: What type of measurement is the channel making. 135 * @channel: What number or name do we wish to assign the channel. 136 * @channel2: If there is a second number for a differential 137 * channel then this is it. If modified is set then the 138 * value here specifies the modifier. 139 * @address: Driver specific identifier. 140 * @scan_index: Monotonic index to give ordering in scans when read 141 * from a buffer. 142 * @scan_type: Sign: 's' or 'u' to specify signed or unsigned 143 * realbits: Number of valid bits of data 144 * storage_bits: Realbits + padding 145 * shift: Shift right by this before masking out 146 * realbits. 147 * endianness: little or big endian 148 * @info_mask: What information is to be exported about this channel. 149 * This includes calibbias, scale etc. 150 * @event_mask: What events can this channel produce. 151 * @ext_info: Array of extended info attributes for this channel. 152 * The array is NULL terminated, the last element should 153 * have it's name field set to NULL. 154 * @extend_name: Allows labeling of channel attributes with an 155 * informative name. Note this has no effect codes etc, 156 * unlike modifiers. 157 * @datasheet_name: A name used in in kernel mapping of channels. It should 158 * correspond to the first name that the channel is referred 159 * to by in the datasheet (e.g. IND), or the nearest 160 * possible compound name (e.g. IND-INC). 161 * @modified: Does a modifier apply to this channel. What these are 162 * depends on the channel type. Modifier is set in 163 * channel2. Examples are IIO_MOD_X for axial sensors about 164 * the 'x' axis. 165 * @indexed: Specify the channel has a numerical index. If not, 166 * the value in channel will be suppressed for attribute 167 * but not for event codes. Typically set it to 0 when 168 * the index is false. 169 * @differential: Channel is differential. 170 */ 171 struct iio_chan_spec { 172 enum iio_chan_type type; 173 int channel; 174 int channel2; 175 unsigned long address; 176 int scan_index; 177 struct { 178 char sign; 179 u8 realbits; 180 u8 storagebits; 181 u8 shift; 182 enum iio_endian endianness; 183 } scan_type; 184 long info_mask; 185 long event_mask; 186 const struct iio_chan_spec_ext_info *ext_info; 187 const char *extend_name; 188 const char *datasheet_name; 189 unsigned modified:1; 190 unsigned indexed:1; 191 unsigned output:1; 192 unsigned differential:1; 193 }; 194 195 #define IIO_ST(si, rb, sb, sh) \ 196 { .sign = si, .realbits = rb, .storagebits = sb, .shift = sh } 197 198 #define IIO_CHAN_SOFT_TIMESTAMP(_si) \ 199 { .type = IIO_TIMESTAMP, .channel = -1, \ 200 .scan_index = _si, .scan_type = IIO_ST('s', 64, 64, 0) } 201 202 /** 203 * iio_get_time_ns() - utility function to get a time stamp for events etc 204 **/ 205 static inline s64 iio_get_time_ns(void) 206 { 207 struct timespec ts; 208 /* 209 * calls getnstimeofday. 210 * If hrtimers then up to ns accurate, if not microsecond. 211 */ 212 ktime_get_real_ts(&ts); 213 214 return timespec_to_ns(&ts); 215 } 216 217 /* Device operating modes */ 218 #define INDIO_DIRECT_MODE 0x01 219 #define INDIO_BUFFER_TRIGGERED 0x02 220 #define INDIO_BUFFER_HARDWARE 0x08 221 222 #define INDIO_ALL_BUFFER_MODES \ 223 (INDIO_BUFFER_TRIGGERED | INDIO_BUFFER_HARDWARE) 224 225 struct iio_trigger; /* forward declaration */ 226 struct iio_dev; 227 228 /** 229 * struct iio_info - constant information about device 230 * @driver_module: module structure used to ensure correct 231 * ownership of chrdevs etc 232 * @event_attrs: event control attributes 233 * @attrs: general purpose device attributes 234 * @read_raw: function to request a value from the device. 235 * mask specifies which value. Note 0 means a reading of 236 * the channel in question. Return value will specify the 237 * type of value returned by the device. val and val2 will 238 * contain the elements making up the returned value. 239 * @write_raw: function to write a value to the device. 240 * Parameters are the same as for read_raw. 241 * @write_raw_get_fmt: callback function to query the expected 242 * format/precision. If not set by the driver, write_raw 243 * returns IIO_VAL_INT_PLUS_MICRO. 244 * @read_event_config: find out if the event is enabled. 245 * @write_event_config: set if the event is enabled. 246 * @read_event_value: read a value associated with the event. Meaning 247 * is event dependant. event_code specifies which event. 248 * @write_event_value: write the value associated with the event. 249 * Meaning is event dependent. 250 * @validate_trigger: function to validate the trigger when the 251 * current trigger gets changed. 252 **/ 253 struct iio_info { 254 struct module *driver_module; 255 struct attribute_group *event_attrs; 256 const struct attribute_group *attrs; 257 258 int (*read_raw)(struct iio_dev *indio_dev, 259 struct iio_chan_spec const *chan, 260 int *val, 261 int *val2, 262 long mask); 263 264 int (*write_raw)(struct iio_dev *indio_dev, 265 struct iio_chan_spec const *chan, 266 int val, 267 int val2, 268 long mask); 269 270 int (*write_raw_get_fmt)(struct iio_dev *indio_dev, 271 struct iio_chan_spec const *chan, 272 long mask); 273 274 int (*read_event_config)(struct iio_dev *indio_dev, 275 u64 event_code); 276 277 int (*write_event_config)(struct iio_dev *indio_dev, 278 u64 event_code, 279 int state); 280 281 int (*read_event_value)(struct iio_dev *indio_dev, 282 u64 event_code, 283 int *val); 284 int (*write_event_value)(struct iio_dev *indio_dev, 285 u64 event_code, 286 int val); 287 int (*validate_trigger)(struct iio_dev *indio_dev, 288 struct iio_trigger *trig); 289 int (*update_scan_mode)(struct iio_dev *indio_dev, 290 const unsigned long *scan_mask); 291 int (*debugfs_reg_access)(struct iio_dev *indio_dev, 292 unsigned reg, unsigned writeval, 293 unsigned *readval); 294 }; 295 296 /** 297 * struct iio_buffer_setup_ops - buffer setup related callbacks 298 * @preenable: [DRIVER] function to run prior to marking buffer enabled 299 * @postenable: [DRIVER] function to run after marking buffer enabled 300 * @predisable: [DRIVER] function to run prior to marking buffer 301 * disabled 302 * @postdisable: [DRIVER] function to run after marking buffer disabled 303 */ 304 struct iio_buffer_setup_ops { 305 int (*preenable)(struct iio_dev *); 306 int (*postenable)(struct iio_dev *); 307 int (*predisable)(struct iio_dev *); 308 int (*postdisable)(struct iio_dev *); 309 }; 310 311 /** 312 * struct iio_dev - industrial I/O device 313 * @id: [INTERN] used to identify device internally 314 * @modes: [DRIVER] operating modes supported by device 315 * @currentmode: [DRIVER] current operating mode 316 * @dev: [DRIVER] device structure, should be assigned a parent 317 * and owner 318 * @event_interface: [INTERN] event chrdevs associated with interrupt lines 319 * @buffer: [DRIVER] any buffer present 320 * @scan_bytes: [INTERN] num bytes captured to be fed to buffer demux 321 * @mlock: [INTERN] lock used to prevent simultaneous device state 322 * changes 323 * @available_scan_masks: [DRIVER] optional array of allowed bitmasks 324 * @masklength: [INTERN] the length of the mask established from 325 * channels 326 * @active_scan_mask: [INTERN] union of all scan masks requested by buffers 327 * @scan_timestamp: [INTERN] set if any buffers have requested timestamp 328 * @scan_index_timestamp:[INTERN] cache of the index to the timestamp 329 * @trig: [INTERN] current device trigger (buffer modes) 330 * @pollfunc: [DRIVER] function run on trigger being received 331 * @channels: [DRIVER] channel specification structure table 332 * @num_channels: [DRIVER] number of chanels specified in @channels. 333 * @channel_attr_list: [INTERN] keep track of automatically created channel 334 * attributes 335 * @chan_attr_group: [INTERN] group for all attrs in base directory 336 * @name: [DRIVER] name of the device. 337 * @info: [DRIVER] callbacks and constant info from driver 338 * @info_exist_lock: [INTERN] lock to prevent use during removal 339 * @setup_ops: [DRIVER] callbacks to call before and after buffer 340 * enable/disable 341 * @chrdev: [INTERN] associated character device 342 * @groups: [INTERN] attribute groups 343 * @groupcounter: [INTERN] index of next attribute group 344 * @flags: [INTERN] file ops related flags including busy flag. 345 * @debugfs_dentry: [INTERN] device specific debugfs dentry. 346 * @cached_reg_addr: [INTERN] cached register address for debugfs reads. 347 */ 348 struct iio_dev { 349 int id; 350 351 int modes; 352 int currentmode; 353 struct device dev; 354 355 struct iio_event_interface *event_interface; 356 357 struct iio_buffer *buffer; 358 int scan_bytes; 359 struct mutex mlock; 360 361 const unsigned long *available_scan_masks; 362 unsigned masklength; 363 const unsigned long *active_scan_mask; 364 bool scan_timestamp; 365 unsigned scan_index_timestamp; 366 struct iio_trigger *trig; 367 struct iio_poll_func *pollfunc; 368 369 struct iio_chan_spec const *channels; 370 int num_channels; 371 372 struct list_head channel_attr_list; 373 struct attribute_group chan_attr_group; 374 const char *name; 375 const struct iio_info *info; 376 struct mutex info_exist_lock; 377 const struct iio_buffer_setup_ops *setup_ops; 378 struct cdev chrdev; 379 #define IIO_MAX_GROUPS 6 380 const struct attribute_group *groups[IIO_MAX_GROUPS + 1]; 381 int groupcounter; 382 383 unsigned long flags; 384 #if defined(CONFIG_DEBUG_FS) 385 struct dentry *debugfs_dentry; 386 unsigned cached_reg_addr; 387 #endif 388 }; 389 390 /** 391 * iio_find_channel_from_si() - get channel from its scan index 392 * @indio_dev: device 393 * @si: scan index to match 394 */ 395 const struct iio_chan_spec 396 *iio_find_channel_from_si(struct iio_dev *indio_dev, int si); 397 398 /** 399 * iio_device_register() - register a device with the IIO subsystem 400 * @indio_dev: Device structure filled by the device driver 401 **/ 402 int iio_device_register(struct iio_dev *indio_dev); 403 404 /** 405 * iio_device_unregister() - unregister a device from the IIO subsystem 406 * @indio_dev: Device structure representing the device. 407 **/ 408 void iio_device_unregister(struct iio_dev *indio_dev); 409 410 /** 411 * iio_push_event() - try to add event to the list for userspace reading 412 * @indio_dev: IIO device structure 413 * @ev_code: What event 414 * @timestamp: When the event occurred 415 **/ 416 int iio_push_event(struct iio_dev *indio_dev, u64 ev_code, s64 timestamp); 417 418 extern struct bus_type iio_bus_type; 419 420 /** 421 * iio_device_put() - reference counted deallocation of struct device 422 * @dev: the iio_device containing the device 423 **/ 424 static inline void iio_device_put(struct iio_dev *indio_dev) 425 { 426 if (indio_dev) 427 put_device(&indio_dev->dev); 428 }; 429 430 /** 431 * dev_to_iio_dev() - Get IIO device struct from a device struct 432 * @dev: The device embedded in the IIO device 433 * 434 * Note: The device must be a IIO device, otherwise the result is undefined. 435 */ 436 static inline struct iio_dev *dev_to_iio_dev(struct device *dev) 437 { 438 return container_of(dev, struct iio_dev, dev); 439 } 440 441 /* Can we make this smaller? */ 442 #define IIO_ALIGN L1_CACHE_BYTES 443 /** 444 * iio_device_alloc() - allocate an iio_dev from a driver 445 * @sizeof_priv: Space to allocate for private structure. 446 **/ 447 struct iio_dev *iio_device_alloc(int sizeof_priv); 448 449 static inline void *iio_priv(const struct iio_dev *indio_dev) 450 { 451 return (char *)indio_dev + ALIGN(sizeof(struct iio_dev), IIO_ALIGN); 452 } 453 454 static inline struct iio_dev *iio_priv_to_dev(void *priv) 455 { 456 return (struct iio_dev *)((char *)priv - 457 ALIGN(sizeof(struct iio_dev), IIO_ALIGN)); 458 } 459 460 /** 461 * iio_device_free() - free an iio_dev from a driver 462 * @dev: the iio_dev associated with the device 463 **/ 464 void iio_device_free(struct iio_dev *indio_dev); 465 466 /** 467 * iio_buffer_enabled() - helper function to test if the buffer is enabled 468 * @indio_dev: IIO device info structure for device 469 **/ 470 static inline bool iio_buffer_enabled(struct iio_dev *indio_dev) 471 { 472 return indio_dev->currentmode 473 & (INDIO_BUFFER_TRIGGERED | INDIO_BUFFER_HARDWARE); 474 }; 475 476 /** 477 * iio_get_debugfs_dentry() - helper function to get the debugfs_dentry 478 * @indio_dev: IIO device info structure for device 479 **/ 480 #if defined(CONFIG_DEBUG_FS) 481 static inline struct dentry *iio_get_debugfs_dentry(struct iio_dev *indio_dev) 482 { 483 return indio_dev->debugfs_dentry; 484 }; 485 #else 486 static inline struct dentry *iio_get_debugfs_dentry(struct iio_dev *indio_dev) 487 { 488 return NULL; 489 }; 490 #endif 491 492 #endif /* _INDUSTRIAL_IO_H_ */ 493