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