1 /* 2 * Copyright (C) 2017 BlueKitchen GmbH 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the copyright holders nor the names of 14 * contributors may be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * 4. Any redistribution, use, or modification is done solely for 17 * personal benefit and not for any commercial purpose or for 18 * monetary gain. 19 * 20 * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 23 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL BLUEKITCHEN 24 * GMBH OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 26 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 27 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 28 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 29 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF 30 * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * Please inquire about commercial licensing options at 34 * [email protected] 35 * 36 */ 37 38 /** 39 * @title HID Parser 40 * 41 * Single-pass HID Report Parser: HID Report is directly parsed without preprocessing HID Descriptor to minimize memory. 42 * 43 */ 44 45 #ifndef BTSTACK_HID_PARSER_H 46 #define BTSTACK_HID_PARSER_H 47 48 #include <stdint.h> 49 #include "btstack_bool.h" 50 #include "btstack_hid.h" 51 52 #if defined __cplusplus 53 extern "C" { 54 #endif 55 56 typedef enum { 57 Main=0, 58 Global, 59 Local, 60 Reserved 61 } TagType; 62 63 typedef enum { 64 Input=8, 65 Output, 66 Coll, 67 Feature, 68 EndColl 69 } MainItemTag; 70 71 typedef enum { 72 UsagePage, 73 LogicalMinimum, 74 LogicalMaximum, 75 PhysicalMinimum, 76 PhysicalMaximum, 77 UnitExponent, 78 Unit, 79 ReportSize, 80 ReportID, 81 ReportCount, 82 Push, 83 Pop 84 } GlobalItemTag; 85 86 typedef enum { 87 Usage, 88 UsageMinimum, 89 UsageMaximum, 90 DesignatorIndex, 91 DesignatorMinimum, 92 DesignatorMaximum, 93 StringIndex, 94 StringMinimum, 95 StringMaximum, 96 Delimiter 97 } LocalItemTag; 98 99 typedef struct { 100 int32_t item_value; 101 uint16_t item_size; 102 uint8_t item_type; 103 uint8_t item_tag; 104 uint8_t data_size; 105 } hid_descriptor_item_t; 106 107 typedef struct { 108 // Descriptor 109 const uint8_t * descriptor; 110 uint16_t descriptor_pos; 111 uint16_t descriptor_len; 112 // parsed item 113 bool item_ready; 114 bool valid; 115 hid_descriptor_item_t descriptor_item; 116 } btstack_hid_descriptor_iterator_t; 117 118 119 typedef enum { 120 BTSTACK_HID_USAGE_ITERATOR_STATE_SCAN_FOR_REPORT_ITEM, 121 BTSTACK_HID_USAGE_ITERATOR_USAGES_AVAILABLE, 122 BTSTACK_HID_USAGE_ITERATOR_PARSER_COMPLETE, 123 } btstack_hid_usage_iterator_state_t; 124 125 typedef struct { 126 // Descriptor 127 const uint8_t * descriptor; 128 uint16_t descriptor_len; 129 btstack_hid_descriptor_iterator_t descriptor_iterator; 130 131 // State 132 btstack_hid_usage_iterator_state_t state; 133 134 hid_descriptor_item_t descriptor_item; 135 136 hid_report_type_t report_type; 137 uint16_t report_pos_in_bit; 138 139 // usage pos and usage_page after last main item, used to find next usage 140 uint16_t usage_pos; 141 uint16_t usage_page; 142 143 // usage generator 144 uint32_t usage_minimum; 145 uint32_t usage_maximum; 146 uint16_t available_usages; 147 uint16_t required_usages; 148 bool usage_range; 149 uint8_t active_record; 150 151 // global 152 int32_t global_logical_minimum; 153 int32_t global_logical_maximum; 154 uint16_t global_usage_page; 155 uint8_t global_report_size; 156 uint8_t global_report_count; 157 uint16_t global_report_id; 158 159 } btstack_hid_usage_iterator_t; 160 161 typedef struct { 162 uint16_t report_id; // 8-bit report ID or 0xffff if not set 163 uint16_t bit_pos; // position in bit 164 uint16_t usage_page; 165 uint16_t usage; 166 uint8_t size; // in bit 167 168 // cached values of relevant descriptor item (input,output,feature) 169 hid_descriptor_item_t descriptor_item; 170 int32_t global_logical_minimum; 171 } btstack_hid_usage_item_t; 172 173 174 typedef struct { 175 btstack_hid_usage_iterator_t usage_iterator; 176 177 const uint8_t * report; 178 uint16_t report_len; 179 180 bool have_report_usage_ready; 181 btstack_hid_usage_item_t descriptor__usage_item; 182 183 } btstack_hid_parser_t; 184 185 186 /* API_START */ 187 188 // HID Descriptor Iterator 189 190 /** 191 * @brief Init HID Descriptor iterator 192 * @param iterator 193 * @param hid_descriptor 194 * @param hid_descriptor_len 195 */ 196 void btstack_hid_descriptor_iterator_init(btstack_hid_descriptor_iterator_t * iterator, const uint8_t * hid_descriptor, uint16_t hid_descriptor_len); 197 198 /** 199 * @brief Check if HID Descriptor Items are available 200 * @param iterator 201 * @return 202 */ 203 bool btstack_hid_descriptor_iterator_has_more(btstack_hid_descriptor_iterator_t * iterator); 204 205 /** 206 * @brief Get next HID Descriptor Item 207 * @param iterator 208 * @return 209 */ 210 const hid_descriptor_item_t * const btstack_hid_descriptor_iterator_get_item(btstack_hid_descriptor_iterator_t * iterator); 211 212 /** 213 * @brief Returns if HID Descriptor was well formed 214 * @param iterator 215 * @return 216 */ 217 bool btstack_hid_descriptor_iterator_valid(btstack_hid_descriptor_iterator_t * iterator); 218 219 220 // HID Descriptor Usage Iterator 221 222 /** 223 * @brief Initialize usages iterator for HID Descriptor and report type 224 * @param parser 225 * @param hid_descriptor 226 * @param hid_descriptor_len 227 * @param hid_report_type 228 */ 229 void btstack_hid_usage_iterator_init(btstack_hid_usage_iterator_t * iterator, const uint8_t * hid_descriptor, uint16_t hid_descriptor_len, hid_report_type_t hid_report_type); 230 231 /** 232 * @brief Checks if more usages are available 233 * @param parser 234 */ 235 bool btstack_hid_usage_iterator_has_more(btstack_hid_usage_iterator_t * iterator); 236 237 /** 238 * @brief Get current usage item 239 * @param parser 240 * @param item 241 */ 242 void btstack_hid_usage_iterator_get_item(btstack_hid_usage_iterator_t * iterator, btstack_hid_usage_item_t * item); 243 244 245 // HID Report Iterator 246 247 /** 248 * @brief Initialize HID Parser. 249 * @param parser state 250 * @param hid_descriptor 251 * @param hid_descriptor_len 252 * @param hid_report_type 253 * @param hid_report 254 * @param hid_report_len 255 */ 256 void btstack_hid_parser_init(btstack_hid_parser_t * parser, const uint8_t * hid_descriptor, uint16_t hid_descriptor_len, hid_report_type_t hid_report_type, const uint8_t * hid_report, uint16_t hid_report_len); 257 258 /** 259 * @brief Checks if more fields are available 260 * @param parser 261 */ 262 bool btstack_hid_parser_has_more(btstack_hid_parser_t * parser); 263 264 /** 265 * @brief Get next field 266 * @param parser 267 * @param usage_page 268 * @param usage 269 * @param value provided in HID report 270 */ 271 void btstack_hid_parser_get_field(btstack_hid_parser_t * parser, uint16_t * usage_page, uint16_t * usage, int32_t * value); 272 273 274 /** 275 * @brief Parses descriptor item 276 * @param item 277 * @param hid_descriptor 278 * @param hid_descriptor_len 279 * @return true if item has been parsed successfully 280 */ 281 bool btstack_hid_parse_descriptor_item(hid_descriptor_item_t * item, const uint8_t * hid_descriptor, uint16_t hid_descriptor_len); 282 283 /** 284 * @brief Parses descriptor and returns report size for given report ID and report type 285 * @param report_id or HID_REPORT_ID_UNDEFINED 286 * @param report_type 287 * @param hid_descriptor 288 * @param hid_descriptor_len 289 * @return report size in bytes or 0 on parsing error 290 */ 291 int btstack_hid_get_report_size_for_id(uint16_t report_id, hid_report_type_t report_type, const uint8_t *hid_descriptor, 292 uint16_t hid_descriptor_len); 293 294 /** 295 * @brief Parses descriptor and returns status for given report ID 296 * @param report_id 297 * @param hid_descriptor 298 * @param hid_descriptor_len 299 * @return status for report id 300 */ 301 hid_report_id_status_t btstack_hid_report_id_valid(uint16_t report_id, const uint8_t * hid_descriptor, uint16_t hid_descriptor_len); 302 303 /** 304 * @brief Parses descriptor and returns true if report ID found 305 * @param hid_descriptor 306 * @param hid_descriptor_len 307 * @return true if report ID declared in descriptor 308 */ 309 bool btstack_hid_report_id_declared(const uint8_t *hid_descriptor, uint16_t hid_descriptor_len); 310 311 312 /* API_END */ 313 314 #if defined __cplusplus 315 } 316 #endif 317 318 #endif // BTSTACK_HID_PARSER_H 319