drivers/gpu/drm/drm_mipi_dsi.c

   1 /*
   2  * MIPI DSI Bus
   3  *
   4  * Copyright (C) 2012-2013, Samsung Electronics, Co., Ltd.
   5  * Andrzej Hajda <a.hajda@samsung.com>
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a
   8  * copy of this software and associated documentation files (the
   9  * "Software"), to deal in the Software without restriction, including
  10  * without limitation the rights to use, copy, modify, merge, publish,
  11  * distribute, sub license, and/or sell copies of the Software, and to
  12  * permit persons to whom the Software is furnished to do so, subject to
  13  * the following conditions:
  14  *
  15  * The above copyright notice and this permission notice (including the
  16  * next paragraph) shall be included in all copies or substantial portions
  17  * of the Software.
  18  *
  19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  20  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  21  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
  22  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
  23  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
  24  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
  25  * USE OR OTHER DEALINGS IN THE SOFTWARE.
  26  */
  27
  28 #include <drm/drm_mipi_dsi.h>
  29
  30 #include <linux/device.h>
  31 #include <linux/module.h>
  32 #include <linux/of_device.h>
  33 #include <linux/pm_runtime.h>
  34 #include <linux/slab.h>
  35
  36 #include <drm/drm_dsc.h>
  37 #include <video/mipi_display.h>
  38
  39 /**
  40  * DOC: dsi helpers
  41  *
  42  * These functions contain some common logic and helpers to deal with MIPI DSI
  43  * peripherals.
  44  *
  45  * Helpers are provided for a number of standard MIPI DSI command as well as a
  46  * subset of the MIPI DCS command set.
  47  */
  48
  49 static int mipi_dsi_device_match(struct device *dev, struct device_driver *drv)
  50 {
  51         struct mipi_dsi_device *dsi = to_mipi_dsi_device(dev);
  52
  53         /* attempt OF style match */
  54         if (of_driver_match_device(dev, drv))
  55                 return 1;
  56
  57         /* compare DSI device and driver names */
  58         if (!strcmp(dsi->name, drv->name))
  59                 return 1;
  60
  61         return 0;
  62 }
  63
  64 static int mipi_dsi_uevent(struct device *dev, struct kobj_uevent_env *env)
  65 {
  66         struct mipi_dsi_device *dsi = to_mipi_dsi_device(dev);
  67         int err;
  68
  69         err = of_device_uevent_modalias(dev, env);
  70         if (err != -ENODEV)
  71                 return err;
  72
  73         add_uevent_var(env, "MODALIAS=%s%s", MIPI_DSI_MODULE_PREFIX,
  74                        dsi->name);
  75
  76         return 0;
  77 }
  78
  79 static const struct dev_pm_ops mipi_dsi_device_pm_ops = {
  80         .runtime_suspend = pm_generic_runtime_suspend,
  81         .runtime_resume = pm_generic_runtime_resume,
  82         .suspend = pm_generic_suspend,
  83         .resume = pm_generic_resume,
  84         .freeze = pm_generic_freeze,
  85         .thaw = pm_generic_thaw,
  86         .poweroff = pm_generic_poweroff,
  87         .restore = pm_generic_restore,
  88 };
  89
  90 static struct bus_type mipi_dsi_bus_type = {
  91         .name = "mipi-dsi",
  92         .match = mipi_dsi_device_match,
  93         .uevent = mipi_dsi_uevent,
  94         .pm = &mipi_dsi_device_pm_ops,
  95 };
  96
  97 /**
  98  * of_find_mipi_dsi_device_by_node() - find the MIPI DSI device matching a
  99  *    device tree node
 100  * @np: device tree node
 101  *
 102  * Return: A pointer to the MIPI DSI device corresponding to @np or NULL if no
 103  *    such device exists (or has not been registered yet).
 104  */
 105 struct mipi_dsi_device *of_find_mipi_dsi_device_by_node(struct device_node *np)
 106 {
 107         struct device *dev;
 108
 109         dev = bus_find_device_by_of_node(&mipi_dsi_bus_type, np);
 110
 111         return dev ? to_mipi_dsi_device(dev) : NULL;
 112 }
 113 EXPORT_SYMBOL(of_find_mipi_dsi_device_by_node);
 114
 115 static void mipi_dsi_dev_release(struct device *dev)
 116 {
 117         struct mipi_dsi_device *dsi = to_mipi_dsi_device(dev);
 118
 119         of_node_put(dev->of_node);
 120         kfree(dsi);
 121 }
 122
 123 static const struct device_type mipi_dsi_device_type = {
 124         .release = mipi_dsi_dev_release,
 125 };
 126
 127 static struct mipi_dsi_device *mipi_dsi_device_alloc(struct mipi_dsi_host *host)
 128 {
 129         struct mipi_dsi_device *dsi;
 130
 131         dsi = kzalloc(sizeof(*dsi), GFP_KERNEL);
 132         if (!dsi)
 133                 return ERR_PTR(-ENOMEM);
 134
 135         dsi->host = host;
 136         dsi->dev.bus = &mipi_dsi_bus_type;
 137         dsi->dev.parent = host->dev;
 138         dsi->dev.type = &mipi_dsi_device_type;
 139
 140         device_initialize(&dsi->dev);
 141
 142         return dsi;
 143 }
 144
 145 static int mipi_dsi_device_add(struct mipi_dsi_device *dsi)
 146 {
 147         struct mipi_dsi_host *host = dsi->host;
 148
 149         dev_set_name(&dsi->dev, "%s.%d", dev_name(host->dev),  dsi->channel);
 150
 151         return device_add(&dsi->dev);
 152 }
 153
 154 #if IS_ENABLED(CONFIG_OF)
 155 static struct mipi_dsi_device *
 156 of_mipi_dsi_device_add(struct mipi_dsi_host *host, struct device_node *node)
 157 {
 158         struct device *dev = host->dev;
 159         struct mipi_dsi_device_info info = { };
 160         int ret;
 161         u32 reg;
 162
 163         if (of_modalias_node(node, info.type, sizeof(info.type)) < 0) {
 164                 dev_err(dev, "modalias failure on %pOF\n", node);
 165                 return ERR_PTR(-EINVAL);
 166         }
 167
 168         ret = of_property_read_u32(node, "reg", &reg);
 169         if (ret) {
 170                 dev_err(dev, "device node %pOF has no valid reg property: %d\n",
 171                         node, ret);
 172                 return ERR_PTR(-EINVAL);
 173         }
 174
 175         info.channel = reg;
 176         info.node = of_node_get(node);
 177
 178         return mipi_dsi_device_register_full(host, &info);
 179 }
 180 #else
 181 static struct mipi_dsi_device *
 182 of_mipi_dsi_device_add(struct mipi_dsi_host *host, struct device_node *node)
 183 {
 184         return ERR_PTR(-ENODEV);
 185 }
 186 #endif
 187
 188 /**
 189  * mipi_dsi_device_register_full - create a MIPI DSI device
 190  * @host: DSI host to which this device is connected
 191  * @info: pointer to template containing DSI device information
 192  *
 193  * Create a MIPI DSI device by using the device information provided by
 194  * mipi_dsi_device_info template
 195  *
 196  * Returns:
 197  * A pointer to the newly created MIPI DSI device, or, a pointer encoded
 198  * with an error
 199  */
 200 struct mipi_dsi_device *
 201 mipi_dsi_device_register_full(struct mipi_dsi_host *host,
 202                               const struct mipi_dsi_device_info *info)
 203 {
 204         struct mipi_dsi_device *dsi;
 205         struct device *dev = host->dev;
 206         int ret;
 207
 208         if (!info) {
 209                 dev_err(dev, "invalid mipi_dsi_device_info pointer\n");
 210                 return ERR_PTR(-EINVAL);
 211         }
 212
 213         if (info->channel > 3) {
 214                 dev_err(dev, "invalid virtual channel: %u\n", info->channel);
 215                 return ERR_PTR(-EINVAL);
 216         }
 217
 218         dsi = mipi_dsi_device_alloc(host);
 219         if (IS_ERR(dsi)) {
 220                 dev_err(dev, "failed to allocate DSI device %ld\n",
 221                         PTR_ERR(dsi));
 222                 return dsi;
 223         }
 224
 225         dsi->dev.of_node = info->node;
 226         dsi->channel = info->channel;
 227         strlcpy(dsi->name, info->type, sizeof(dsi->name));
 228
 229         ret = mipi_dsi_device_add(dsi);
 230         if (ret) {
 231                 dev_err(dev, "failed to add DSI device %d\n", ret);
 232                 kfree(dsi);
 233                 return ERR_PTR(ret);
 234         }
 235
 236         return dsi;
 237 }
 238 EXPORT_SYMBOL(mipi_dsi_device_register_full);
 239
 240 /**
 241  * mipi_dsi_device_unregister - unregister MIPI DSI device
 242  * @dsi: DSI peripheral device
 243  */
 244 void mipi_dsi_device_unregister(struct mipi_dsi_device *dsi)
 245 {
 246         device_unregister(&dsi->dev);
 247 }
 248 EXPORT_SYMBOL(mipi_dsi_device_unregister);
 249
 250 static DEFINE_MUTEX(host_lock);
 251 static LIST_HEAD(host_list);
 252
 253 /**
 254  * of_find_mipi_dsi_host_by_node() - find the MIPI DSI host matching a
 255  *                                   device tree node
 256  * @node: device tree node
 257  *
 258  * Returns:
 259  * A pointer to the MIPI DSI host corresponding to @node or NULL if no
 260  * such device exists (or has not been registered yet).
 261  */
 262 struct mipi_dsi_host *of_find_mipi_dsi_host_by_node(struct device_node *node)
 263 {
 264         struct mipi_dsi_host *host;
 265
 266         mutex_lock(&host_lock);
 267
 268         list_for_each_entry(host, &host_list, list) {
 269                 if (host->dev->of_node == node) {
 270                         mutex_unlock(&host_lock);
 271                         return host;
 272                 }
 273         }
 274
 275         mutex_unlock(&host_lock);
 276
 277         return NULL;
 278 }
 279 EXPORT_SYMBOL(of_find_mipi_dsi_host_by_node);
 280
 281 int mipi_dsi_host_register(struct mipi_dsi_host *host)
 282 {
 283         struct device_node *node;
 284
 285         for_each_available_child_of_node(host->dev->of_node, node) {
 286                 /* skip nodes without reg property */
 287                 if (!of_find_property(node, "reg", NULL))
 288                         continue;
 289                 of_mipi_dsi_device_add(host, node);
 290         }
 291
 292         mutex_lock(&host_lock);
 293         list_add_tail(&host->list, &host_list);
 294         mutex_unlock(&host_lock);
 295
 296         return 0;
 297 }
 298 EXPORT_SYMBOL(mipi_dsi_host_register);
 299
 300 static int mipi_dsi_remove_device_fn(struct device *dev, void *priv)
 301 {
 302         struct mipi_dsi_device *dsi = to_mipi_dsi_device(dev);
 303
 304         mipi_dsi_device_unregister(dsi);
 305
 306         return 0;
 307 }
 308
 309 void mipi_dsi_host_unregister(struct mipi_dsi_host *host)
 310 {
 311         device_for_each_child(host->dev, NULL, mipi_dsi_remove_device_fn);
 312
 313         mutex_lock(&host_lock);
 314         list_del_init(&host->list);
 315         mutex_unlock(&host_lock);
 316 }
 317 EXPORT_SYMBOL(mipi_dsi_host_unregister);
 318
 319 /**
 320  * mipi_dsi_attach - attach a DSI device to its DSI host
 321  * @dsi: DSI peripheral
 322  */
 323 int mipi_dsi_attach(struct mipi_dsi_device *dsi)
 324 {
 325         const struct mipi_dsi_host_ops *ops = dsi->host->ops;
 326
 327         if (!ops || !ops->attach)
 328                 return -ENOSYS;
 329
 330         return ops->attach(dsi->host, dsi);
 331 }
 332 EXPORT_SYMBOL(mipi_dsi_attach);
 333
 334 /**
 335  * mipi_dsi_detach - detach a DSI device from its DSI host
 336  * @dsi: DSI peripheral
 337  */
 338 int mipi_dsi_detach(struct mipi_dsi_device *dsi)
 339 {
 340         const struct mipi_dsi_host_ops *ops = dsi->host->ops;
 341
 342         if (!ops || !ops->detach)
 343                 return -ENOSYS;
 344
 345         return ops->detach(dsi->host, dsi);
 346 }
 347 EXPORT_SYMBOL(mipi_dsi_detach);
 348
 349 static ssize_t mipi_dsi_device_transfer(struct mipi_dsi_device *dsi,
 350                                         struct mipi_dsi_msg *msg)
 351 {
 352         const struct mipi_dsi_host_ops *ops = dsi->host->ops;
 353
 354         if (!ops || !ops->transfer)
 355                 return -ENOSYS;
 356
 357         if (dsi->mode_flags & MIPI_DSI_MODE_LPM)
 358                 msg->flags |= MIPI_DSI_MSG_USE_LPM;
 359
 360         return ops->transfer(dsi->host, msg);
 361 }
 362
 363 /**
 364  * mipi_dsi_packet_format_is_short - check if a packet is of the short format
 365  * @type: MIPI DSI data type of the packet
 366  *
 367  * Return: true if the packet for the given data type is a short packet, false
 368  * otherwise.
 369  */
 370 bool mipi_dsi_packet_format_is_short(u8 type)
 371 {
 372         switch (type) {
 373         case MIPI_DSI_V_SYNC_START:
 374         case MIPI_DSI_V_SYNC_END:
 375         case MIPI_DSI_H_SYNC_START:
 376         case MIPI_DSI_H_SYNC_END:
 377         case MIPI_DSI_COMPRESSION_MODE:
 378         case MIPI_DSI_END_OF_TRANSMISSION:
 379         case MIPI_DSI_COLOR_MODE_OFF:
 380         case MIPI_DSI_COLOR_MODE_ON:
 381         case MIPI_DSI_SHUTDOWN_PERIPHERAL:
 382         case MIPI_DSI_TURN_ON_PERIPHERAL:
 383         case MIPI_DSI_GENERIC_SHORT_WRITE_0_PARAM:
 384         case MIPI_DSI_GENERIC_SHORT_WRITE_1_PARAM:
 385         case MIPI_DSI_GENERIC_SHORT_WRITE_2_PARAM:
 386         case MIPI_DSI_GENERIC_READ_REQUEST_0_PARAM:
 387         case MIPI_DSI_GENERIC_READ_REQUEST_1_PARAM:
 388         case MIPI_DSI_GENERIC_READ_REQUEST_2_PARAM:
 389         case MIPI_DSI_DCS_SHORT_WRITE:
 390         case MIPI_DSI_DCS_SHORT_WRITE_PARAM:
 391         case MIPI_DSI_DCS_READ:
 392         case MIPI_DSI_EXECUTE_QUEUE:
 393         case MIPI_DSI_SET_MAXIMUM_RETURN_PACKET_SIZE:
 394                 return true;
 395         }
 396
 397         return false;
 398 }
 399 EXPORT_SYMBOL(mipi_dsi_packet_format_is_short);
 400
 401 /**
 402  * mipi_dsi_packet_format_is_long - check if a packet is of the long format
 403  * @type: MIPI DSI data type of the packet
 404  *
 405  * Return: true if the packet for the given data type is a long packet, false
 406  * otherwise.
 407  */
 408 bool mipi_dsi_packet_format_is_long(u8 type)
 409 {
 410         switch (type) {
 411         case MIPI_DSI_NULL_PACKET:
 412         case MIPI_DSI_BLANKING_PACKET:
 413         case MIPI_DSI_GENERIC_LONG_WRITE:
 414         case MIPI_DSI_DCS_LONG_WRITE:
 415         case MIPI_DSI_PICTURE_PARAMETER_SET:
 416         case MIPI_DSI_COMPRESSED_PIXEL_STREAM:
 417         case MIPI_DSI_LOOSELY_PACKED_PIXEL_STREAM_YCBCR20:
 418         case MIPI_DSI_PACKED_PIXEL_STREAM_YCBCR24:
 419         case MIPI_DSI_PACKED_PIXEL_STREAM_YCBCR16:
 420         case MIPI_DSI_PACKED_PIXEL_STREAM_30:
 421         case MIPI_DSI_PACKED_PIXEL_STREAM_36:
 422         case MIPI_DSI_PACKED_PIXEL_STREAM_YCBCR12:
 423         case MIPI_DSI_PACKED_PIXEL_STREAM_16:
 424         case MIPI_DSI_PACKED_PIXEL_STREAM_18:
 425         case MIPI_DSI_PIXEL_STREAM_3BYTE_18:
 426         case MIPI_DSI_PACKED_PIXEL_STREAM_24:
 427                 return true;
 428         }
 429
 430         return false;
 431 }
 432 EXPORT_SYMBOL(mipi_dsi_packet_format_is_long);
 433
 434 /**
 435  * mipi_dsi_create_packet - create a packet from a message according to the
 436  *     DSI protocol
 437  * @packet: pointer to a DSI packet structure
 438  * @msg: message to translate into a packet
 439  *
 440  * Return: 0 on success or a negative error code on failure.
 441  */
 442 int mipi_dsi_create_packet(struct mipi_dsi_packet *packet,
 443                            const struct mipi_dsi_msg *msg)
 444 {
 445         if (!packet || !msg)
 446                 return -EINVAL;
 447
 448         /* do some minimum sanity checking */
 449         if (!mipi_dsi_packet_format_is_short(msg->type) &&
 450             !mipi_dsi_packet_format_is_long(msg->type))
 451                 return -EINVAL;
 452
 453         if (msg->channel > 3)
 454                 return -EINVAL;
 455
 456         memset(packet, 0, sizeof(*packet));
 457         packet->header[0] = ((msg->channel & 0x3) << 6) | (msg->type & 0x3f);
 458
 459         /* TODO: compute ECC if hardware support is not available */
 460
 461         /*
 462          * Long write packets contain the word count in header bytes 1 and 2.
 463          * The payload follows the header and is word count bytes long.
 464          *
 465          * Short write packets encode up to two parameters in header bytes 1
 466          * and 2.
 467          */
 468         if (mipi_dsi_packet_format_is_long(msg->type)) {
 469                 packet->header[1] = (msg->tx_len >> 0) & 0xff;
 470                 packet->header[2] = (msg->tx_len >> 8) & 0xff;
 471
 472                 packet->payload_length = msg->tx_len;
 473                 packet->payload = msg->tx_buf;
 474         } else {
 475                 const u8 *tx = msg->tx_buf;
 476
 477                 packet->header[1] = (msg->tx_len > 0) ? tx[0] : 0;
 478                 packet->header[2] = (msg->tx_len > 1) ? tx[1] : 0;
 479         }
 480
 481         packet->size = sizeof(packet->header) + packet->payload_length;
 482
 483         return 0;
 484 }
 485 EXPORT_SYMBOL(mipi_dsi_create_packet);
 486
 487 /**
 488  * mipi_dsi_shutdown_peripheral() - sends a Shutdown Peripheral command
 489  * @dsi: DSI peripheral device
 490  *
 491  * Return: 0 on success or a negative error code on failure.
 492  */
 493 int mipi_dsi_shutdown_peripheral(struct mipi_dsi_device *dsi)
 494 {
 495         struct mipi_dsi_msg msg = {
 496                 .channel = dsi->channel,
 497                 .type = MIPI_DSI_SHUTDOWN_PERIPHERAL,
 498                 .tx_buf = (u8 [2]) { 0, 0 },
 499                 .tx_len = 2,
 500         };
 501         int ret = mipi_dsi_device_transfer(dsi, &msg);
 502
 503         return (ret < 0) ? ret : 0;
 504 }
 505 EXPORT_SYMBOL(mipi_dsi_shutdown_peripheral);
 506
 507 /**
 508  * mipi_dsi_turn_on_peripheral() - sends a Turn On Peripheral command
 509  * @dsi: DSI peripheral device
 510  *
 511  * Return: 0 on success or a negative error code on failure.
 512  */
 513 int mipi_dsi_turn_on_peripheral(struct mipi_dsi_device *dsi)
 514 {
 515         struct mipi_dsi_msg msg = {
 516                 .channel = dsi->channel,
 517                 .type = MIPI_DSI_TURN_ON_PERIPHERAL,
 518                 .tx_buf = (u8 [2]) { 0, 0 },
 519                 .tx_len = 2,
 520         };
 521         int ret = mipi_dsi_device_transfer(dsi, &msg);
 522
 523         return (ret < 0) ? ret : 0;
 524 }
 525 EXPORT_SYMBOL(mipi_dsi_turn_on_peripheral);
 526
 527 /*
 528  * mipi_dsi_set_maximum_return_packet_size() - specify the maximum size of the
 529  *    the payload in a long packet transmitted from the peripheral back to the
 530  *    host processor
 531  * @dsi: DSI peripheral device
 532  * @value: the maximum size of the payload
 533  *
 534  * Return: 0 on success or a negative error code on failure.
 535  */
 536 int mipi_dsi_set_maximum_return_packet_size(struct mipi_dsi_device *dsi,
 537                                             u16 value)
 538 {
 539         u8 tx[2] = { value & 0xff, value >> 8 };
 540         struct mipi_dsi_msg msg = {
 541                 .channel = dsi->channel,
 542                 .type = MIPI_DSI_SET_MAXIMUM_RETURN_PACKET_SIZE,
 543                 .tx_len = sizeof(tx),
 544                 .tx_buf = tx,
 545         };
 546         int ret = mipi_dsi_device_transfer(dsi, &msg);
 547
 548         return (ret < 0) ? ret : 0;
 549 }
 550 EXPORT_SYMBOL(mipi_dsi_set_maximum_return_packet_size);
 551
 552 /**
 553  * mipi_dsi_compression_mode() - enable/disable DSC on the peripheral
 554  * @dsi: DSI peripheral device
 555  * @enable: Whether to enable or disable the DSC
 556  *
 557  * Enable or disable Display Stream Compression on the peripheral using the
 558  * default Picture Parameter Set and VESA DSC 1.1 algorithm.
 559  *
 560  * Return: 0 on success or a negative error code on failure.
 561  */
 562 ssize_t mipi_dsi_compression_mode(struct mipi_dsi_device *dsi, bool enable)
 563 {
 564         /* Note: Needs updating for non-default PPS or algorithm */
 565         u8 tx[2] = { enable << 0, 0 };
 566         struct mipi_dsi_msg msg = {
 567                 .channel = dsi->channel,
 568                 .type = MIPI_DSI_COMPRESSION_MODE,
 569                 .tx_len = sizeof(tx),
 570                 .tx_buf = tx,
 571         };
 572         int ret = mipi_dsi_device_transfer(dsi, &msg);
 573
 574         return (ret < 0) ? ret : 0;
 575 }
 576 EXPORT_SYMBOL(mipi_dsi_compression_mode);
 577
 578 /**
 579  * mipi_dsi_picture_parameter_set() - transmit the DSC PPS to the peripheral
 580  * @dsi: DSI peripheral device
 581  * @pps: VESA DSC 1.1 Picture Parameter Set
 582  *
 583  * Transmit the VESA DSC 1.1 Picture Parameter Set to the peripheral.
 584  *
 585  * Return: 0 on success or a negative error code on failure.
 586  */
 587 ssize_t mipi_dsi_picture_parameter_set(struct mipi_dsi_device *dsi,
 588                                        const struct drm_dsc_picture_parameter_set *pps)
 589 {
 590         struct mipi_dsi_msg msg = {
 591                 .channel = dsi->channel,
 592                 .type = MIPI_DSI_PICTURE_PARAMETER_SET,
 593                 .tx_len = sizeof(*pps),
 594                 .tx_buf = pps,
 595         };
 596         int ret = mipi_dsi_device_transfer(dsi, &msg);
 597
 598         return (ret < 0) ? ret : 0;
 599 }
 600 EXPORT_SYMBOL(mipi_dsi_picture_parameter_set);
 601
 602 /**
 603  * mipi_dsi_generic_write() - transmit data using a generic write packet
 604  * @dsi: DSI peripheral device
 605  * @payload: buffer containing the payload
 606  * @size: size of payload buffer
 607  *
 608  * This function will automatically choose the right data type depending on
 609  * the payload length.
 610  *
 611  * Return: The number of bytes transmitted on success or a negative error code
 612  * on failure.
 613  */
 614 ssize_t mipi_dsi_generic_write(struct mipi_dsi_device *dsi, const void *payload,
 615                                size_t size)
 616 {
 617         struct mipi_dsi_msg msg = {
 618                 .channel = dsi->channel,
 619                 .tx_buf = payload,
 620                 .tx_len = size
 621         };
 622
 623         switch (size) {
 624         case 0:
 625                 msg.type = MIPI_DSI_GENERIC_SHORT_WRITE_0_PARAM;
 626                 break;
 627
 628         case 1:
 629                 msg.type = MIPI_DSI_GENERIC_SHORT_WRITE_1_PARAM;
 630                 break;
 631
 632         case 2:
 633                 msg.type = MIPI_DSI_GENERIC_SHORT_WRITE_2_PARAM;
 634                 break;
 635
 636         default:
 637                 msg.type = MIPI_DSI_GENERIC_LONG_WRITE;
 638                 break;
 639         }
 640
 641         return mipi_dsi_device_transfer(dsi, &msg);
 642 }
 643 EXPORT_SYMBOL(mipi_dsi_generic_write);
 644
 645 /**
 646  * mipi_dsi_generic_read() - receive data using a generic read packet
 647  * @dsi: DSI peripheral device
 648  * @params: buffer containing the request parameters
 649  * @num_params: number of request parameters
 650  * @data: buffer in which to return the received data
 651  * @size: size of receive buffer
 652  *
 653  * This function will automatically choose the right data type depending on
 654  * the number of parameters passed in.
 655  *
 656  * Return: The number of bytes successfully read or a negative error code on
 657  * failure.
 658  */
 659 ssize_t mipi_dsi_generic_read(struct mipi_dsi_device *dsi, const void *params,
 660                               size_t num_params, void *data, size_t size)
 661 {
 662         struct mipi_dsi_msg msg = {
 663                 .channel = dsi->channel,
 664                 .tx_len = num_params,
 665                 .tx_buf = params,
 666                 .rx_len = size,
 667                 .rx_buf = data
 668         };
 669
 670         switch (num_params) {
 671         case 0:
 672                 msg.type = MIPI_DSI_GENERIC_READ_REQUEST_0_PARAM;
 673                 break;
 674
 675         case 1:
 676                 msg.type = MIPI_DSI_GENERIC_READ_REQUEST_1_PARAM;
 677                 break;
 678
 679         case 2:
 680                 msg.type = MIPI_DSI_GENERIC_READ_REQUEST_2_PARAM;
 681                 break;
 682
 683         default:
 684                 return -EINVAL;
 685         }
 686
 687         return mipi_dsi_device_transfer(dsi, &msg);
 688 }
 689 EXPORT_SYMBOL(mipi_dsi_generic_read);
 690
 691 /**
 692  * mipi_dsi_dcs_write_buffer() - transmit a DCS command with payload
 693  * @dsi: DSI peripheral device
 694  * @data: buffer containing data to be transmitted
 695  * @len: size of transmission buffer
 696  *
 697  * This function will automatically choose the right data type depending on
 698  * the command payload length.
 699  *
 700  * Return: The number of bytes successfully transmitted or a negative error
 701  * code on failure.
 702  */
 703 ssize_t mipi_dsi_dcs_write_buffer(struct mipi_dsi_device *dsi,
 704                                   const void *data, size_t len)
 705 {
 706         struct mipi_dsi_msg msg = {
 707                 .channel = dsi->channel,
 708                 .tx_buf = data,
 709                 .tx_len = len
 710         };
 711
 712         switch (len) {
 713         case 0:
 714                 return -EINVAL;
 715
 716         case 1:
 717                 msg.type = MIPI_DSI_DCS_SHORT_WRITE;
 718                 break;
 719
 720         case 2:
 721                 msg.type = MIPI_DSI_DCS_SHORT_WRITE_PARAM;
 722                 break;
 723
 724         default:
 725                 msg.type = MIPI_DSI_DCS_LONG_WRITE;
 726                 break;
 727         }
 728
 729         return mipi_dsi_device_transfer(dsi, &msg);
 730 }
 731 EXPORT_SYMBOL(mipi_dsi_dcs_write_buffer);
 732
 733 /**
 734  * mipi_dsi_dcs_write() - send DCS write command
 735  * @dsi: DSI peripheral device
 736  * @cmd: DCS command
 737  * @data: buffer containing the command payload
 738  * @len: command payload length
 739  *
 740  * This function will automatically choose the right data type depending on
 741  * the command payload length.
 742  *
 743  * Return: The number of bytes successfully transmitted or a negative error
 744  * code on failure.
 745  */
 746 ssize_t mipi_dsi_dcs_write(struct mipi_dsi_device *dsi, u8 cmd,
 747                            const void *data, size_t len)
 748 {
 749         ssize_t err;
 750         size_t size;
 751         u8 *tx;
 752
 753         if (len > 0) {
 754                 size = 1 + len;
 755
 756                 tx = kmalloc(size, GFP_KERNEL);
 757                 if (!tx)
 758                         return -ENOMEM;
 759
 760                 /* concatenate the DCS command byte and the payload */
 761                 tx[0] = cmd;
 762                 memcpy(&tx[1], data, len);
 763         } else {
 764                 tx = &cmd;
 765                 size = 1;
 766         }
 767
 768         err = mipi_dsi_dcs_write_buffer(dsi, tx, size);
 769
 770         if (len > 0)
 771                 kfree(tx);
 772
 773         return err;
 774 }
 775 EXPORT_SYMBOL(mipi_dsi_dcs_write);
 776
 777 /**
 778  * mipi_dsi_dcs_read() - send DCS read request command
 779  * @dsi: DSI peripheral device
 780  * @cmd: DCS command
 781  * @data: buffer in which to receive data
 782  * @len: size of receive buffer
 783  *
 784  * Return: The number of bytes read or a negative error code on failure.
 785  */
 786 ssize_t mipi_dsi_dcs_read(struct mipi_dsi_device *dsi, u8 cmd, void *data,
 787                           size_t len)
 788 {
 789         struct mipi_dsi_msg msg = {
 790                 .channel = dsi->channel,
 791                 .type = MIPI_DSI_DCS_READ,
 792                 .tx_buf = &cmd,
 793                 .tx_len = 1,
 794                 .rx_buf = data,
 795                 .rx_len = len
 796         };
 797
 798         return mipi_dsi_device_transfer(dsi, &msg);
 799 }
 800 EXPORT_SYMBOL(mipi_dsi_dcs_read);
 801
 802 /**
 803  * mipi_dsi_dcs_nop() - send DCS nop packet
 804  * @dsi: DSI peripheral device
 805  *
 806  * Return: 0 on success or a negative error code on failure.
 807  */
 808 int mipi_dsi_dcs_nop(struct mipi_dsi_device *dsi)
 809 {
 810         ssize_t err;
 811
 812         err = mipi_dsi_dcs_write(dsi, MIPI_DCS_NOP, NULL, 0);
 813         if (err < 0)
 814                 return err;
 815
 816         return 0;
 817 }
 818 EXPORT_SYMBOL(mipi_dsi_dcs_nop);
 819
 820 /**
 821  * mipi_dsi_dcs_soft_reset() - perform a software reset of the display module
 822  * @dsi: DSI peripheral device
 823  *
 824  * Return: 0 on success or a negative error code on failure.
 825  */
 826 int mipi_dsi_dcs_soft_reset(struct mipi_dsi_device *dsi)
 827 {
 828         ssize_t err;
 829
 830         err = mipi_dsi_dcs_write(dsi, MIPI_DCS_SOFT_RESET, NULL, 0);
 831         if (err < 0)
 832                 return err;
 833
 834         return 0;
 835 }
 836 EXPORT_SYMBOL(mipi_dsi_dcs_soft_reset);
 837
 838 /**
 839  * mipi_dsi_dcs_get_power_mode() - query the display module's current power
 840  *    mode
 841  * @dsi: DSI peripheral device
 842  * @mode: return location for the current power mode
 843  *
 844  * Return: 0 on success or a negative error code on failure.
 845  */
 846 int mipi_dsi_dcs_get_power_mode(struct mipi_dsi_device *dsi, u8 *mode)
 847 {
 848         ssize_t err;
 849
 850         err = mipi_dsi_dcs_read(dsi, MIPI_DCS_GET_POWER_MODE, mode,
 851                                 sizeof(*mode));
 852         if (err <= 0) {
 853                 if (err == 0)
 854                         err = -ENODATA;
 855
 856                 return err;
 857         }
 858
 859         return 0;
 860 }
 861 EXPORT_SYMBOL(mipi_dsi_dcs_get_power_mode);
 862
 863 /**
 864  * mipi_dsi_dcs_get_pixel_format() - gets the pixel format for the RGB image
 865  *    data used by the interface
 866  * @dsi: DSI peripheral device
 867  * @format: return location for the pixel format
 868  *
 869  * Return: 0 on success or a negative error code on failure.
 870  */
 871 int mipi_dsi_dcs_get_pixel_format(struct mipi_dsi_device *dsi, u8 *format)
 872 {
 873         ssize_t err;
 874
 875         err = mipi_dsi_dcs_read(dsi, MIPI_DCS_GET_PIXEL_FORMAT, format,
 876                                 sizeof(*format));
 877         if (err <= 0) {
 878                 if (err == 0)
 879                         err = -ENODATA;
 880
 881                 return err;
 882         }
 883
 884         return 0;
 885 }
 886 EXPORT_SYMBOL(mipi_dsi_dcs_get_pixel_format);
 887
 888 /**
 889  * mipi_dsi_dcs_enter_sleep_mode() - disable all unnecessary blocks inside the
 890  *    display module except interface communication
 891  * @dsi: DSI peripheral device
 892  *
 893  * Return: 0 on success or a negative error code on failure.
 894  */
 895 int mipi_dsi_dcs_enter_sleep_mode(struct mipi_dsi_device *dsi)
 896 {
 897         ssize_t err;
 898
 899         err = mipi_dsi_dcs_write(dsi, MIPI_DCS_ENTER_SLEEP_MODE, NULL, 0);
 900         if (err < 0)
 901                 return err;
 902
 903         return 0;
 904 }
 905 EXPORT_SYMBOL(mipi_dsi_dcs_enter_sleep_mode);
 906
 907 /**
 908  * mipi_dsi_dcs_exit_sleep_mode() - enable all blocks inside the display
 909  *    module
 910  * @dsi: DSI peripheral device
 911  *
 912  * Return: 0 on success or a negative error code on failure.
 913  */
 914 int mipi_dsi_dcs_exit_sleep_mode(struct mipi_dsi_device *dsi)
 915 {
 916         ssize_t err;
 917
 918         err = mipi_dsi_dcs_write(dsi, MIPI_DCS_EXIT_SLEEP_MODE, NULL, 0);
 919         if (err < 0)
 920                 return err;
 921
 922         return 0;
 923 }
 924 EXPORT_SYMBOL(mipi_dsi_dcs_exit_sleep_mode);
 925
 926 /**
 927  * mipi_dsi_dcs_set_display_off() - stop displaying the image data on the
 928  *    display device
 929  * @dsi: DSI peripheral device
 930  *
 931  * Return: 0 on success or a negative error code on failure.
 932  */
 933 int mipi_dsi_dcs_set_display_off(struct mipi_dsi_device *dsi)
 934 {
 935         ssize_t err;
 936
 937         err = mipi_dsi_dcs_write(dsi, MIPI_DCS_SET_DISPLAY_OFF, NULL, 0);
 938         if (err < 0)
 939                 return err;
 940
 941         return 0;
 942 }
 943 EXPORT_SYMBOL(mipi_dsi_dcs_set_display_off);
 944
 945 /**
 946  * mipi_dsi_dcs_set_display_on() - start displaying the image data on the
 947  *    display device
 948  * @dsi: DSI peripheral device
 949  *
 950  * Return: 0 on success or a negative error code on failure
 951  */
 952 int mipi_dsi_dcs_set_display_on(struct mipi_dsi_device *dsi)
 953 {
 954         ssize_t err;
 955
 956         err = mipi_dsi_dcs_write(dsi, MIPI_DCS_SET_DISPLAY_ON, NULL, 0);
 957         if (err < 0)
 958                 return err;
 959
 960         return 0;
 961 }
 962 EXPORT_SYMBOL(mipi_dsi_dcs_set_display_on);
 963
 964 /**
 965  * mipi_dsi_dcs_set_column_address() - define the column extent of the frame
 966  *    memory accessed by the host processor
 967  * @dsi: DSI peripheral device
 968  * @start: first column of frame memory
 969  * @end: last column of frame memory
 970  *
 971  * Return: 0 on success or a negative error code on failure.
 972  */
 973 int mipi_dsi_dcs_set_column_address(struct mipi_dsi_device *dsi, u16 start,
 974                                     u16 end)
 975 {
 976         u8 payload[4] = { start >> 8, start & 0xff, end >> 8, end & 0xff };
 977         ssize_t err;
 978
 979         err = mipi_dsi_dcs_write(dsi, MIPI_DCS_SET_COLUMN_ADDRESS, payload,
 980                                  sizeof(payload));
 981         if (err < 0)
 982                 return err;
 983
 984         return 0;
 985 }
 986 EXPORT_SYMBOL(mipi_dsi_dcs_set_column_address);
 987
 988 /**
 989  * mipi_dsi_dcs_set_page_address() - define the page extent of the frame
 990  *    memory accessed by the host processor
 991  * @dsi: DSI peripheral device
 992  * @start: first page of frame memory
 993  * @end: last page of frame memory
 994  *
 995  * Return: 0 on success or a negative error code on failure.
 996  */
 997 int mipi_dsi_dcs_set_page_address(struct mipi_dsi_device *dsi, u16 start,
 998                                   u16 end)
 999 {
1000         u8 payload[4] = { start >> 8, start & 0xff, end >> 8, end & 0xff };
1001         ssize_t err;
1002
1003         err = mipi_dsi_dcs_write(dsi, MIPI_DCS_SET_PAGE_ADDRESS, payload,
1004                                  sizeof(payload));
1005         if (err < 0)
1006                 return err;
1007
1008         return 0;
1009 }
1010 EXPORT_SYMBOL(mipi_dsi_dcs_set_page_address);
1011
1012 /**
1013  * mipi_dsi_dcs_set_tear_off() - turn off the display module's Tearing Effect
1014  *    output signal on the TE signal line
1015  * @dsi: DSI peripheral device
1016  *
1017  * Return: 0 on success or a negative error code on failure
1018  */
1019 int mipi_dsi_dcs_set_tear_off(struct mipi_dsi_device *dsi)
1020 {
1021         ssize_t err;
1022
1023         err = mipi_dsi_dcs_write(dsi, MIPI_DCS_SET_TEAR_OFF, NULL, 0);
1024         if (err < 0)
1025                 return err;
1026
1027         return 0;
1028 }
1029 EXPORT_SYMBOL(mipi_dsi_dcs_set_tear_off);
1030
1031 /**
1032  * mipi_dsi_dcs_set_tear_on() - turn on the display module's Tearing Effect
1033  *    output signal on the TE signal line.
1034  * @dsi: DSI peripheral device
1035  * @mode: the Tearing Effect Output Line mode
1036  *
1037  * Return: 0 on success or a negative error code on failure
1038  */
1039 int mipi_dsi_dcs_set_tear_on(struct mipi_dsi_device *dsi,
1040                              enum mipi_dsi_dcs_tear_mode mode)
1041 {
1042         u8 value = mode;
1043         ssize_t err;
1044
1045         err = mipi_dsi_dcs_write(dsi, MIPI_DCS_SET_TEAR_ON, &value,
1046                                  sizeof(value));
1047         if (err < 0)
1048                 return err;
1049
1050         return 0;
1051 }
1052 EXPORT_SYMBOL(mipi_dsi_dcs_set_tear_on);
1053
1054 /**
1055  * mipi_dsi_dcs_set_pixel_format() - sets the pixel format for the RGB image
1056  *    data used by the interface
1057  * @dsi: DSI peripheral device
1058  * @format: pixel format
1059  *
1060  * Return: 0 on success or a negative error code on failure.
1061  */
1062 int mipi_dsi_dcs_set_pixel_format(struct mipi_dsi_device *dsi, u8 format)
1063 {
1064         ssize_t err;
1065
1066         err = mipi_dsi_dcs_write(dsi, MIPI_DCS_SET_PIXEL_FORMAT, &format,
1067                                  sizeof(format));
1068         if (err < 0)
1069                 return err;
1070
1071         return 0;
1072 }
1073 EXPORT_SYMBOL(mipi_dsi_dcs_set_pixel_format);
1074
1075 /**
1076  * mipi_dsi_dcs_set_tear_scanline() - set the scanline to use as trigger for
1077  *    the Tearing Effect output signal of the display module
1078  * @dsi: DSI peripheral device
1079  * @scanline: scanline to use as trigger
1080  *
1081  * Return: 0 on success or a negative error code on failure
1082  */
1083 int mipi_dsi_dcs_set_tear_scanline(struct mipi_dsi_device *dsi, u16 scanline)
1084 {
1085         u8 payload[3] = { MIPI_DCS_SET_TEAR_SCANLINE, scanline >> 8,
1086                           scanline & 0xff };
1087         ssize_t err;
1088
1089         err = mipi_dsi_generic_write(dsi, payload, sizeof(payload));
1090         if (err < 0)
1091                 return err;
1092
1093         return 0;
1094 }
1095 EXPORT_SYMBOL(mipi_dsi_dcs_set_tear_scanline);
1096
1097 /**
1098  * mipi_dsi_dcs_set_display_brightness() - sets the brightness value of the
1099  *    display
1100  * @dsi: DSI peripheral device
1101  * @brightness: brightness value
1102  *
1103  * Return: 0 on success or a negative error code on failure.
1104  */
1105 int mipi_dsi_dcs_set_display_brightness(struct mipi_dsi_device *dsi,
1106                                         u16 brightness)
1107 {
1108         u8 payload[2] = { brightness & 0xff, brightness >> 8 };
1109         ssize_t err;
1110
1111         err = mipi_dsi_dcs_write(dsi, MIPI_DCS_SET_DISPLAY_BRIGHTNESS,
1112                                  payload, sizeof(payload));
1113         if (err < 0)
1114                 return err;
1115
1116         return 0;
1117 }
1118 EXPORT_SYMBOL(mipi_dsi_dcs_set_display_brightness);
1119
1120 /**
1121  * mipi_dsi_dcs_get_display_brightness() - gets the current brightness value
1122  *    of the display
1123  * @dsi: DSI peripheral device
1124  * @brightness: brightness value
1125  *
1126  * Return: 0 on success or a negative error code on failure.
1127  */
1128 int mipi_dsi_dcs_get_display_brightness(struct mipi_dsi_device *dsi,
1129                                         u16 *brightness)
1130 {
1131         ssize_t err;
1132
1133         err = mipi_dsi_dcs_read(dsi, MIPI_DCS_GET_DISPLAY_BRIGHTNESS,
1134                                 brightness, sizeof(*brightness));
1135         if (err <= 0) {
1136                 if (err == 0)
1137                         err = -ENODATA;
1138
1139                 return err;
1140         }
1141
1142         return 0;
1143 }
1144 EXPORT_SYMBOL(mipi_dsi_dcs_get_display_brightness);
1145
1146 static int mipi_dsi_drv_probe(struct device *dev)
1147 {
1148         struct mipi_dsi_driver *drv = to_mipi_dsi_driver(dev->driver);
1149         struct mipi_dsi_device *dsi = to_mipi_dsi_device(dev);
1150
1151         return drv->probe(dsi);
1152 }
1153
1154 static int mipi_dsi_drv_remove(struct device *dev)
1155 {
1156         struct mipi_dsi_driver *drv = to_mipi_dsi_driver(dev->driver);
1157         struct mipi_dsi_device *dsi = to_mipi_dsi_device(dev);
1158
1159         return drv->remove(dsi);
1160 }
1161
1162 static void mipi_dsi_drv_shutdown(struct device *dev)
1163 {
1164         struct mipi_dsi_driver *drv = to_mipi_dsi_driver(dev->driver);
1165         struct mipi_dsi_device *dsi = to_mipi_dsi_device(dev);
1166
1167         drv->shutdown(dsi);
1168 }
1169
1170 /**
1171  * mipi_dsi_driver_register_full() - register a driver for DSI devices
1172  * @drv: DSI driver structure
1173  * @owner: owner module
1174  *
1175  * Return: 0 on success or a negative error code on failure.
1176  */
1177 int mipi_dsi_driver_register_full(struct mipi_dsi_driver *drv,
1178                                   struct module *owner)
1179 {
1180         drv->driver.bus = &mipi_dsi_bus_type;
1181         drv->driver.owner = owner;
1182
1183         if (drv->probe)
1184                 drv->driver.probe = mipi_dsi_drv_probe;
1185         if (drv->remove)
1186                 drv->driver.remove = mipi_dsi_drv_remove;
1187         if (drv->shutdown)
1188                 drv->driver.shutdown = mipi_dsi_drv_shutdown;
1189
1190         return driver_register(&drv->driver);
1191 }
1192 EXPORT_SYMBOL(mipi_dsi_driver_register_full);
1193
1194 /**
1195  * mipi_dsi_driver_unregister() - unregister a driver for DSI devices
1196  * @drv: DSI driver structure
1197  *
1198  * Return: 0 on success or a negative error code on failure.
1199  */
1200 void mipi_dsi_driver_unregister(struct mipi_dsi_driver *drv)
1201 {
1202         driver_unregister(&drv->driver);
1203 }
1204 EXPORT_SYMBOL(mipi_dsi_driver_unregister);
1205
1206 static int __init mipi_dsi_bus_init(void)
1207 {
1208         return bus_register(&mipi_dsi_bus_type);
1209 }
1210 postcore_initcall(mipi_dsi_bus_init);
1211
1212 MODULE_AUTHOR("Andrzej Hajda <a.hajda@samsung.com>");
1213 MODULE_DESCRIPTION("MIPI DSI Bus");
1214 MODULE_LICENSE("GPL and additional rights");