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 enum { 108 BTSTACK_HID_PARSER_SCAN_FOR_REPORT_ITEM, 109 BTSTACK_HID_PARSER_USAGES_AVAILABLE, 110 BTSTACK_HID_PARSER_COMPLETE, 111 } btstack_hid_parser_state_t; 112 113 typedef struct { 114 // Descriptor 115 const uint8_t * descriptor; 116 uint16_t descriptor_pos; 117 uint16_t descriptor_len; 118 // parsed item 119 bool item_ready; 120 bool valid; 121 hid_descriptor_item_t descriptor_item; 122 } btstack_hid_descriptor_iterator_t; 123 124 typedef struct { 125 uint16_t report_id; // 8-bit report ID or 0xffff if not set 126 uint16_t bit_pos; // position in bit 127 uint16_t usage_page; 128 uint16_t usage; 129 uint8_t size; // in bit 130 } btstack_hid_usage_item_t; 131 132 typedef struct { 133 134 // Descriptor 135 const uint8_t * descriptor; 136 uint16_t descriptor_len; 137 btstack_hid_descriptor_iterator_t descriptor_iterator; 138 139 // Report 140 hid_report_type_t report_type; 141 const uint8_t * report; 142 uint16_t report_len; 143 144 // State 145 btstack_hid_parser_state_t state; 146 147 hid_descriptor_item_t descriptor_item; 148 149 uint16_t report_pos_in_bit; 150 151 // usage pos and usage_page after last main item, used to find next usage 152 uint16_t usage_pos; 153 uint16_t usage_page; 154 155 // usage generator 156 uint32_t usage_minimum; 157 uint32_t usage_maximum; 158 uint16_t available_usages; 159 uint16_t required_usages; 160 bool usage_range; 161 uint8_t active_record; 162 163 // global 164 int32_t global_logical_minimum; 165 int32_t global_logical_maximum; 166 uint16_t global_usage_page; 167 uint8_t global_report_size; 168 uint8_t global_report_count; 169 uint8_t global_report_id; 170 } btstack_hid_parser_t; 171 172 173 /* API_START */ 174 175 /** 176 * @brief Init HID Descriptor iterator 177 * @param iterator 178 * @param hid_descriptor 179 * @param hid_descriptor_len 180 */ 181 void btstack_hid_descriptor_iterator_init(btstack_hid_descriptor_iterator_t * iterator, const uint8_t * hid_descriptor, uint16_t hid_descriptor_len); 182 183 /** 184 * @brief Check if HID Descriptor Items are available 185 * @param iterator 186 * @return 187 */ 188 bool btstack_hid_descriptor_iterator_has_more(btstack_hid_descriptor_iterator_t * iterator); 189 190 /** 191 * @brief Get next HID Descriptor Item 192 * @param iterator 193 * @return 194 */ 195 const hid_descriptor_item_t * const btstack_hid_descriptor_iterator_get_item(btstack_hid_descriptor_iterator_t * iterator); 196 197 /** 198 * @brief Returns if HID Descriptor was well formed 199 * @param iterator 200 * @return 201 */ 202 bool btstack_hid_descriptor_iterator_valid(btstack_hid_descriptor_iterator_t * iterator); 203 204 205 /** 206 * @brief Initialize usages iterator for HID Descriptor and report type 207 * @param parser 208 * @param hid_descriptor 209 * @param hid_descriptor_len 210 * @param hid_report_type 211 */ 212 void btstack_hid_usage_iterator_init(btstack_hid_parser_t * parser, const uint8_t * hid_descriptor, uint16_t hid_descriptor_len, hid_report_type_t hid_report_type); 213 214 /** 215 * @brief Checks if more usages are available 216 * @param parser 217 */ 218 bool btstack_hid_usage_iterator_has_more(btstack_hid_parser_t * parser); 219 220 /** 221 * @brief Get current usage item 222 * @param parser 223 * @param item 224 */ 225 void btstack_hid_usage_iterator_get_item(btstack_hid_parser_t * parser, btstack_hid_usage_item_t * item); 226 227 228 /** 229 * @brief Initialize HID Parser. 230 * @param parser state 231 * @param hid_descriptor 232 * @param hid_descriptor_len 233 * @param hid_report_type 234 * @param hid_report 235 * @param hid_report_len 236 */ 237 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); 238 239 /** 240 * @brief Checks if more fields are available 241 * @param parser 242 */ 243 bool btstack_hid_parser_has_more(btstack_hid_parser_t * parser); 244 245 /** 246 * @brief Get next field 247 * @param parser 248 * @param usage_page 249 * @param usage 250 * @param value provided in HID report 251 */ 252 void btstack_hid_parser_get_field(btstack_hid_parser_t * parser, uint16_t * usage_page, uint16_t * usage, int32_t * value); 253 254 255 /** 256 * @brief Parses descriptor item 257 * @param item 258 * @param hid_descriptor 259 * @param hid_descriptor_len 260 * @return true if item has been parsed successfully 261 */ 262 bool btstack_hid_parse_descriptor_item(hid_descriptor_item_t * item, const uint8_t * hid_descriptor, uint16_t hid_descriptor_len); 263 264 /** 265 * @brief Parses descriptor and returns report size for given report ID and report type 266 * @param report_id 267 * @param report_type 268 * @param hid_descriptor_len 269 * @param hid_descriptor 270 * @return report size in bytes or 0 on parsing error 271 */ 272 int btstack_hid_get_report_size_for_id(int report_id, hid_report_type_t report_type, uint16_t hid_descriptor_len, const uint8_t * hid_descriptor); 273 274 /** 275 * @brief Parses descriptor and returns status for given report ID 276 * @param report_id 277 * @param hid_descriptor_len 278 * @param hid_descriptor 279 * @return status for report id 280 */ 281 hid_report_id_status_t btstack_hid_id_valid(int report_id, uint16_t hid_descriptor_len, const uint8_t * hid_descriptor); 282 283 /** 284 * @brief Parses descriptor and returns true if report ID found 285 * @param hid_descriptor_len 286 * @param hid_descriptor 287 * @return true if report ID declared in descriptor 288 */ 289 bool btstack_hid_report_id_declared(uint16_t hid_descriptor_len, const uint8_t * hid_descriptor); 290 291 /* API_END */ 292 293 #if defined __cplusplus 294 } 295 #endif 296 297 #endif // BTSTACK_HID_PARSER_H 298