1 /* 2 * Copyright (C) 2012 Avionic Design GmbH 3 * 4 * Permission is hereby granted, free of charge, to any person obtaining a 5 * copy of this software and associated documentation files (the "Software"), 6 * to deal in the Software without restriction, including without limitation 7 * the rights to use, copy, modify, merge, publish, distribute, sub license, 8 * and/or sell copies of the Software, and to permit persons to whom the 9 * Software is furnished to do so, subject to the following conditions: 10 * 11 * The above copyright notice and this permission notice (including the 12 * next paragraph) shall be included in all copies or substantial portions 13 * of the Software. 14 * 15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 17 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL 18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 21 * DEALINGS IN THE SOFTWARE. 22 */ 23 24 #include <linux/bitops.h> 25 #include <linux/errno.h> 26 #include <linux/export.h> 27 #include <linux/hdmi.h> 28 #include <linux/string.h> 29 30 static void hdmi_infoframe_checksum(void *buffer, size_t size) 31 { 32 u8 *ptr = buffer; 33 u8 csum = 0; 34 size_t i; 35 36 /* compute checksum */ 37 for (i = 0; i < size; i++) 38 csum += ptr[i]; 39 40 ptr[3] = 256 - csum; 41 } 42 43 /** 44 * hdmi_avi_infoframe_init() - initialize an HDMI AVI infoframe 45 * @frame: HDMI AVI infoframe 46 * 47 * Returns 0 on success or a negative error code on failure. 48 */ 49 int hdmi_avi_infoframe_init(struct hdmi_avi_infoframe *frame) 50 { 51 memset(frame, 0, sizeof(*frame)); 52 53 frame->type = HDMI_INFOFRAME_TYPE_AVI; 54 frame->version = 2; 55 frame->length = 13; 56 57 return 0; 58 } 59 EXPORT_SYMBOL(hdmi_avi_infoframe_init); 60 61 /** 62 * hdmi_avi_infoframe_pack() - write HDMI AVI infoframe to binary buffer 63 * @frame: HDMI AVI infoframe 64 * @buffer: destination buffer 65 * @size: size of buffer 66 * 67 * Packs the information contained in the @frame structure into a binary 68 * representation that can be written into the corresponding controller 69 * registers. Also computes the checksum as required by section 5.3.5 of 70 * the HDMI 1.4 specification. 71 * 72 * Returns the number of bytes packed into the binary buffer or a negative 73 * error code on failure. 74 */ 75 ssize_t hdmi_avi_infoframe_pack(struct hdmi_avi_infoframe *frame, void *buffer, 76 size_t size) 77 { 78 u8 *ptr = buffer; 79 size_t length; 80 81 length = HDMI_INFOFRAME_HEADER_SIZE + frame->length; 82 83 if (size < length) 84 return -ENOSPC; 85 86 memset(buffer, 0, length); 87 88 ptr[0] = frame->type; 89 ptr[1] = frame->version; 90 ptr[2] = frame->length; 91 ptr[3] = 0; /* checksum */ 92 93 /* start infoframe payload */ 94 ptr += HDMI_INFOFRAME_HEADER_SIZE; 95 96 ptr[0] = ((frame->colorspace & 0x3) << 5) | (frame->scan_mode & 0x3); 97 98 if (frame->active_info_valid) 99 ptr[0] |= BIT(4); 100 101 if (frame->horizontal_bar_valid) 102 ptr[0] |= BIT(3); 103 104 if (frame->vertical_bar_valid) 105 ptr[0] |= BIT(2); 106 107 ptr[1] = ((frame->colorimetry & 0x3) << 6) | 108 ((frame->picture_aspect & 0x3) << 4) | 109 (frame->active_aspect & 0xf); 110 111 ptr[2] = ((frame->extended_colorimetry & 0x7) << 4) | 112 ((frame->quantization_range & 0x3) << 2) | 113 (frame->nups & 0x3); 114 115 if (frame->itc) 116 ptr[2] |= BIT(7); 117 118 ptr[3] = frame->video_code & 0x7f; 119 120 ptr[4] = ((frame->ycc_quantization_range & 0x3) << 6) | 121 ((frame->content_type & 0x3) << 4) | 122 (frame->pixel_repeat & 0xf); 123 124 ptr[5] = frame->top_bar & 0xff; 125 ptr[6] = (frame->top_bar >> 8) & 0xff; 126 ptr[7] = frame->bottom_bar & 0xff; 127 ptr[8] = (frame->bottom_bar >> 8) & 0xff; 128 ptr[9] = frame->left_bar & 0xff; 129 ptr[10] = (frame->left_bar >> 8) & 0xff; 130 ptr[11] = frame->right_bar & 0xff; 131 ptr[12] = (frame->right_bar >> 8) & 0xff; 132 133 hdmi_infoframe_checksum(buffer, length); 134 135 return length; 136 } 137 EXPORT_SYMBOL(hdmi_avi_infoframe_pack); 138 139 /** 140 * hdmi_spd_infoframe_init() - initialize an HDMI SPD infoframe 141 * @frame: HDMI SPD infoframe 142 * @vendor: vendor string 143 * @product: product string 144 * 145 * Returns 0 on success or a negative error code on failure. 146 */ 147 int hdmi_spd_infoframe_init(struct hdmi_spd_infoframe *frame, 148 const char *vendor, const char *product) 149 { 150 memset(frame, 0, sizeof(*frame)); 151 152 frame->type = HDMI_INFOFRAME_TYPE_SPD; 153 frame->version = 1; 154 frame->length = 25; 155 156 strncpy(frame->vendor, vendor, sizeof(frame->vendor)); 157 strncpy(frame->product, product, sizeof(frame->product)); 158 159 return 0; 160 } 161 EXPORT_SYMBOL(hdmi_spd_infoframe_init); 162 163 /** 164 * hdmi_spd_infoframe_pack() - write HDMI SPD infoframe to binary buffer 165 * @frame: HDMI SPD infoframe 166 * @buffer: destination buffer 167 * @size: size of buffer 168 * 169 * Packs the information contained in the @frame structure into a binary 170 * representation that can be written into the corresponding controller 171 * registers. Also computes the checksum as required by section 5.3.5 of 172 * the HDMI 1.4 specification. 173 * 174 * Returns the number of bytes packed into the binary buffer or a negative 175 * error code on failure. 176 */ 177 ssize_t hdmi_spd_infoframe_pack(struct hdmi_spd_infoframe *frame, void *buffer, 178 size_t size) 179 { 180 u8 *ptr = buffer; 181 size_t length; 182 183 length = HDMI_INFOFRAME_HEADER_SIZE + frame->length; 184 185 if (size < length) 186 return -ENOSPC; 187 188 memset(buffer, 0, length); 189 190 ptr[0] = frame->type; 191 ptr[1] = frame->version; 192 ptr[2] = frame->length; 193 ptr[3] = 0; /* checksum */ 194 195 /* start infoframe payload */ 196 ptr += HDMI_INFOFRAME_HEADER_SIZE; 197 198 memcpy(ptr, frame->vendor, sizeof(frame->vendor)); 199 memcpy(ptr + 8, frame->product, sizeof(frame->product)); 200 201 ptr[24] = frame->sdi; 202 203 hdmi_infoframe_checksum(buffer, length); 204 205 return length; 206 } 207 EXPORT_SYMBOL(hdmi_spd_infoframe_pack); 208 209 /** 210 * hdmi_audio_infoframe_init() - initialize an HDMI audio infoframe 211 * @frame: HDMI audio infoframe 212 * 213 * Returns 0 on success or a negative error code on failure. 214 */ 215 int hdmi_audio_infoframe_init(struct hdmi_audio_infoframe *frame) 216 { 217 memset(frame, 0, sizeof(*frame)); 218 219 frame->type = HDMI_INFOFRAME_TYPE_AUDIO; 220 frame->version = 1; 221 frame->length = 10; 222 223 return 0; 224 } 225 EXPORT_SYMBOL(hdmi_audio_infoframe_init); 226 227 /** 228 * hdmi_audio_infoframe_pack() - write HDMI audio infoframe to binary buffer 229 * @frame: HDMI audio infoframe 230 * @buffer: destination buffer 231 * @size: size of buffer 232 * 233 * Packs the information contained in the @frame structure into a binary 234 * representation that can be written into the corresponding controller 235 * registers. Also computes the checksum as required by section 5.3.5 of 236 * the HDMI 1.4 specification. 237 * 238 * Returns the number of bytes packed into the binary buffer or a negative 239 * error code on failure. 240 */ 241 ssize_t hdmi_audio_infoframe_pack(struct hdmi_audio_infoframe *frame, 242 void *buffer, size_t size) 243 { 244 unsigned char channels; 245 u8 *ptr = buffer; 246 size_t length; 247 248 length = HDMI_INFOFRAME_HEADER_SIZE + frame->length; 249 250 if (size < length) 251 return -ENOSPC; 252 253 memset(buffer, 0, length); 254 255 if (frame->channels >= 2) 256 channels = frame->channels - 1; 257 else 258 channels = 0; 259 260 ptr[0] = frame->type; 261 ptr[1] = frame->version; 262 ptr[2] = frame->length; 263 ptr[3] = 0; /* checksum */ 264 265 /* start infoframe payload */ 266 ptr += HDMI_INFOFRAME_HEADER_SIZE; 267 268 ptr[0] = ((frame->coding_type & 0xf) << 4) | (channels & 0x7); 269 ptr[1] = ((frame->sample_frequency & 0x7) << 2) | 270 (frame->sample_size & 0x3); 271 ptr[2] = frame->coding_type_ext & 0x1f; 272 ptr[3] = frame->channel_allocation; 273 ptr[4] = (frame->level_shift_value & 0xf) << 3; 274 275 if (frame->downmix_inhibit) 276 ptr[4] |= BIT(7); 277 278 hdmi_infoframe_checksum(buffer, length); 279 280 return length; 281 } 282 EXPORT_SYMBOL(hdmi_audio_infoframe_pack); 283 284 /** 285 * hdmi_vendor_infoframe_pack() - write a HDMI vendor infoframe to binary 286 * buffer 287 * @frame: HDMI vendor infoframe 288 * @buffer: destination buffer 289 * @size: size of buffer 290 * 291 * Packs the information contained in the @frame structure into a binary 292 * representation that can be written into the corresponding controller 293 * registers. Also computes the checksum as required by section 5.3.5 of 294 * the HDMI 1.4 specification. 295 * 296 * Returns the number of bytes packed into the binary buffer or a negative 297 * error code on failure. 298 */ 299 ssize_t hdmi_vendor_infoframe_pack(struct hdmi_vendor_infoframe *frame, 300 void *buffer, size_t size) 301 { 302 u8 *ptr = buffer; 303 size_t length; 304 305 length = HDMI_INFOFRAME_HEADER_SIZE + frame->length; 306 307 if (size < length) 308 return -ENOSPC; 309 310 memset(buffer, 0, length); 311 312 ptr[0] = frame->type; 313 ptr[1] = frame->version; 314 ptr[2] = frame->length; 315 ptr[3] = 0; /* checksum */ 316 317 memcpy(&ptr[HDMI_INFOFRAME_HEADER_SIZE], frame->data, frame->length); 318 319 hdmi_infoframe_checksum(buffer, length); 320 321 return length; 322 } 323 EXPORT_SYMBOL(hdmi_vendor_infoframe_pack); 324