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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * MIPI Display Bus Interface (DBI) LCD controller support
4 *
5 * Copyright 2016 Noralf Trønnes
6 */
7
8#include <linux/backlight.h>
9#include <linux/debugfs.h>
10#include <linux/delay.h>
11#include <linux/gpio/consumer.h>
12#include <linux/module.h>
13#include <linux/regulator/consumer.h>
14#include <linux/spi/spi.h>
15
16#include <drm/drm_connector.h>
17#include <drm/drm_damage_helper.h>
18#include <drm/drm_drv.h>
19#include <drm/drm_file.h>
20#include <drm/drm_format_helper.h>
21#include <drm/drm_fourcc.h>
22#include <drm/drm_framebuffer.h>
23#include <drm/drm_gem.h>
24#include <drm/drm_gem_atomic_helper.h>
25#include <drm/drm_gem_framebuffer_helper.h>
26#include <drm/drm_mipi_dbi.h>
27#include <drm/drm_modes.h>
28#include <drm/drm_probe_helper.h>
29#include <drm/drm_rect.h>
30#include <video/mipi_display.h>
31
32#define MIPI_DBI_MAX_SPI_READ_SPEED 2000000 /* 2MHz */
33
34#define DCS_POWER_MODE_DISPLAY BIT(2)
35#define DCS_POWER_MODE_DISPLAY_NORMAL_MODE BIT(3)
36#define DCS_POWER_MODE_SLEEP_MODE BIT(4)
37#define DCS_POWER_MODE_PARTIAL_MODE BIT(5)
38#define DCS_POWER_MODE_IDLE_MODE BIT(6)
39#define DCS_POWER_MODE_RESERVED_MASK (BIT(0) | BIT(1) | BIT(7))
40
41/**
42 * DOC: overview
43 *
44 * This library provides helpers for MIPI Display Bus Interface (DBI)
45 * compatible display controllers.
46 *
47 * Many controllers for tiny lcd displays are MIPI compliant and can use this
48 * library. If a controller uses registers 0x2A and 0x2B to set the area to
49 * update and uses register 0x2C to write to frame memory, it is most likely
50 * MIPI compliant.
51 *
52 * Only MIPI Type 1 displays are supported since a full frame memory is needed.
53 *
54 * There are 3 MIPI DBI implementation types:
55 *
56 * A. Motorola 6800 type parallel bus
57 *
58 * B. Intel 8080 type parallel bus
59 *
60 * C. SPI type with 3 options:
61 *
62 * 1. 9-bit with the Data/Command signal as the ninth bit
63 * 2. Same as above except it's sent as 16 bits
64 * 3. 8-bit with the Data/Command signal as a separate D/CX pin
65 *
66 * Currently mipi_dbi only supports Type C options 1 and 3 with
67 * mipi_dbi_spi_init().
68 */
69
70#define MIPI_DBI_DEBUG_COMMAND(cmd, data, len) \
71({ \
72 if (!len) \
73 DRM_DEBUG_DRIVER("cmd=%02x\n", cmd); \
74 else if (len <= 32) \
75 DRM_DEBUG_DRIVER("cmd=%02x, par=%*ph\n", cmd, (int)len, data);\
76 else \
77 DRM_DEBUG_DRIVER("cmd=%02x, len=%zu\n", cmd, len); \
78})
79
80static const u8 mipi_dbi_dcs_read_commands[] = {
81 MIPI_DCS_GET_DISPLAY_ID,
82 MIPI_DCS_GET_RED_CHANNEL,
83 MIPI_DCS_GET_GREEN_CHANNEL,
84 MIPI_DCS_GET_BLUE_CHANNEL,
85 MIPI_DCS_GET_DISPLAY_STATUS,
86 MIPI_DCS_GET_POWER_MODE,
87 MIPI_DCS_GET_ADDRESS_MODE,
88 MIPI_DCS_GET_PIXEL_FORMAT,
89 MIPI_DCS_GET_DISPLAY_MODE,
90 MIPI_DCS_GET_SIGNAL_MODE,
91 MIPI_DCS_GET_DIAGNOSTIC_RESULT,
92 MIPI_DCS_READ_MEMORY_START,
93 MIPI_DCS_READ_MEMORY_CONTINUE,
94 MIPI_DCS_GET_SCANLINE,
95 MIPI_DCS_GET_DISPLAY_BRIGHTNESS,
96 MIPI_DCS_GET_CONTROL_DISPLAY,
97 MIPI_DCS_GET_POWER_SAVE,
98 MIPI_DCS_GET_CABC_MIN_BRIGHTNESS,
99 MIPI_DCS_READ_DDB_START,
100 MIPI_DCS_READ_DDB_CONTINUE,
101 0, /* sentinel */
102};
103
104static bool mipi_dbi_command_is_read(struct mipi_dbi *dbi, u8 cmd)
105{
106 unsigned int i;
107
108 if (!dbi->read_commands)
109 return false;
110
111 for (i = 0; i < 0xff; i++) {
112 if (!dbi->read_commands[i])
113 return false;
114 if (cmd == dbi->read_commands[i])
115 return true;
116 }
117
118 return false;
119}
120
121/**
122 * mipi_dbi_command_read - MIPI DCS read command
123 * @dbi: MIPI DBI structure
124 * @cmd: Command
125 * @val: Value read
126 *
127 * Send MIPI DCS read command to the controller.
128 *
129 * Returns:
130 * Zero on success, negative error code on failure.
131 */
132int mipi_dbi_command_read(struct mipi_dbi *dbi, u8 cmd, u8 *val)
133{
134 if (!dbi->read_commands)
135 return -EACCES;
136
137 if (!mipi_dbi_command_is_read(dbi, cmd))
138 return -EINVAL;
139
140 return mipi_dbi_command_buf(dbi, cmd, val, 1);
141}
142EXPORT_SYMBOL(mipi_dbi_command_read);
143
144/**
145 * mipi_dbi_command_buf - MIPI DCS command with parameter(s) in an array
146 * @dbi: MIPI DBI structure
147 * @cmd: Command
148 * @data: Parameter buffer
149 * @len: Buffer length
150 *
151 * Returns:
152 * Zero on success, negative error code on failure.
153 */
154int mipi_dbi_command_buf(struct mipi_dbi *dbi, u8 cmd, u8 *data, size_t len)
155{
156 u8 *cmdbuf;
157 int ret;
158
159 /* SPI requires dma-safe buffers */
160 cmdbuf = kmemdup(&cmd, 1, GFP_KERNEL);
161 if (!cmdbuf)
162 return -ENOMEM;
163
164 mutex_lock(&dbi->cmdlock);
165 ret = dbi->command(dbi, cmdbuf, data, len);
166 mutex_unlock(&dbi->cmdlock);
167
168 kfree(cmdbuf);
169
170 return ret;
171}
172EXPORT_SYMBOL(mipi_dbi_command_buf);
173
174/* This should only be used by mipi_dbi_command() */
175int mipi_dbi_command_stackbuf(struct mipi_dbi *dbi, u8 cmd, const u8 *data,
176 size_t len)
177{
178 u8 *buf;
179 int ret;
180
181 buf = kmemdup(data, len, GFP_KERNEL);
182 if (!buf)
183 return -ENOMEM;
184
185 ret = mipi_dbi_command_buf(dbi, cmd, buf, len);
186
187 kfree(buf);
188
189 return ret;
190}
191EXPORT_SYMBOL(mipi_dbi_command_stackbuf);
192
193/**
194 * mipi_dbi_buf_copy - Copy a framebuffer, transforming it if necessary
195 * @dst: The destination buffer
196 * @src: The source buffer
197 * @fb: The source framebuffer
198 * @clip: Clipping rectangle of the area to be copied
199 * @swap: When true, swap MSB/LSB of 16-bit values
200 * @fmtcnv_state: Format-conversion state
201 *
202 * Returns:
203 * Zero on success, negative error code on failure.
204 */
205int mipi_dbi_buf_copy(void *dst, struct iosys_map *src, struct drm_framebuffer *fb,
206 struct drm_rect *clip, bool swap,
207 struct drm_format_conv_state *fmtcnv_state)
208{
209 struct mipi_dbi_dev *dbidev = drm_to_mipi_dbi_dev(fb->dev);
210 struct drm_gem_object *gem = drm_gem_fb_get_obj(fb, 0);
211 struct iosys_map dst_map = IOSYS_MAP_INIT_VADDR(dst);
212 int ret;
213
214 ret = drm_gem_fb_begin_cpu_access(fb, DMA_FROM_DEVICE);
215 if (ret)
216 return ret;
217
218 switch (fb->format->format) {
219 case DRM_FORMAT_RGB565:
220 if (swap)
221 drm_fb_swab(&dst_map, NULL, src, fb, clip, !gem->import_attach,
222 fmtcnv_state);
223 else
224 drm_fb_memcpy(&dst_map, NULL, src, fb, clip);
225 break;
226 case DRM_FORMAT_RGB888:
227 drm_fb_memcpy(&dst_map, NULL, src, fb, clip);
228 break;
229 case DRM_FORMAT_XRGB8888:
230 switch (dbidev->pixel_format) {
231 case DRM_FORMAT_RGB565:
232 drm_fb_xrgb8888_to_rgb565(&dst_map, NULL, src, fb, clip, fmtcnv_state, swap);
233 break;
234 case DRM_FORMAT_RGB888:
235 drm_fb_xrgb8888_to_rgb888(&dst_map, NULL, src, fb, clip, fmtcnv_state);
236 break;
237 }
238 break;
239 default:
240 drm_err_once(fb->dev, "Format is not supported: %p4cc\n",
241 &fb->format->format);
242 ret = -EINVAL;
243 }
244
245 drm_gem_fb_end_cpu_access(fb, DMA_FROM_DEVICE);
246
247 return ret;
248}
249EXPORT_SYMBOL(mipi_dbi_buf_copy);
250
251static void mipi_dbi_set_window_address(struct mipi_dbi_dev *dbidev,
252 unsigned int xs, unsigned int xe,
253 unsigned int ys, unsigned int ye)
254{
255 struct mipi_dbi *dbi = &dbidev->dbi;
256
257 xs += dbidev->left_offset;
258 xe += dbidev->left_offset;
259 ys += dbidev->top_offset;
260 ye += dbidev->top_offset;
261
262 mipi_dbi_command(dbi, MIPI_DCS_SET_COLUMN_ADDRESS, (xs >> 8) & 0xff,
263 xs & 0xff, (xe >> 8) & 0xff, xe & 0xff);
264 mipi_dbi_command(dbi, MIPI_DCS_SET_PAGE_ADDRESS, (ys >> 8) & 0xff,
265 ys & 0xff, (ye >> 8) & 0xff, ye & 0xff);
266}
267
268static void mipi_dbi_fb_dirty(struct iosys_map *src, struct drm_framebuffer *fb,
269 struct drm_rect *rect, struct drm_format_conv_state *fmtcnv_state)
270{
271 struct mipi_dbi_dev *dbidev = drm_to_mipi_dbi_dev(fb->dev);
272 unsigned int height = rect->y2 - rect->y1;
273 unsigned int width = rect->x2 - rect->x1;
274 const struct drm_format_info *dst_format;
275 struct mipi_dbi *dbi = &dbidev->dbi;
276 bool swap = dbi->swap_bytes;
277 int ret = 0;
278 size_t len;
279 bool full;
280 void *tr;
281
282 full = width == fb->width && height == fb->height;
283
284 DRM_DEBUG_KMS("Flushing [FB:%d] " DRM_RECT_FMT "\n", fb->base.id, DRM_RECT_ARG(rect));
285
286 if (!dbi->dc || !full || swap ||
287 fb->format->format == DRM_FORMAT_XRGB8888) {
288 tr = dbidev->tx_buf;
289 ret = mipi_dbi_buf_copy(tr, src, fb, rect, swap, fmtcnv_state);
290 if (ret)
291 goto err_msg;
292 } else {
293 tr = src->vaddr; /* TODO: Use mapping abstraction properly */
294 }
295
296 mipi_dbi_set_window_address(dbidev, rect->x1, rect->x2 - 1, rect->y1,
297 rect->y2 - 1);
298
299 if (fb->format->format == DRM_FORMAT_XRGB8888)
300 dst_format = drm_format_info(dbidev->pixel_format);
301 else
302 dst_format = fb->format;
303 len = drm_format_info_min_pitch(dst_format, 0, width) * height;
304
305 ret = mipi_dbi_command_buf(dbi, MIPI_DCS_WRITE_MEMORY_START, tr, len);
306err_msg:
307 if (ret)
308 drm_err_once(fb->dev, "Failed to update display %d\n", ret);
309}
310
311/**
312 * mipi_dbi_pipe_mode_valid - MIPI DBI mode-valid helper
313 * @pipe: Simple display pipe
314 * @mode: The mode to test
315 *
316 * This function validates a given display mode against the MIPI DBI's hardware
317 * display. Drivers can use this as their &drm_simple_display_pipe_funcs->mode_valid
318 * callback.
319 */
320enum drm_mode_status mipi_dbi_pipe_mode_valid(struct drm_simple_display_pipe *pipe,
321 const struct drm_display_mode *mode)
322{
323 struct mipi_dbi_dev *dbidev = drm_to_mipi_dbi_dev(pipe->crtc.dev);
324
325 return drm_crtc_helper_mode_valid_fixed(&pipe->crtc, mode, &dbidev->mode);
326}
327EXPORT_SYMBOL(mipi_dbi_pipe_mode_valid);
328
329/**
330 * mipi_dbi_pipe_update - Display pipe update helper
331 * @pipe: Simple display pipe
332 * @old_state: Old plane state
333 *
334 * This function handles framebuffer flushing and vblank events. Drivers can use
335 * this as their &drm_simple_display_pipe_funcs->update callback.
336 */
337void mipi_dbi_pipe_update(struct drm_simple_display_pipe *pipe,
338 struct drm_plane_state *old_state)
339{
340 struct drm_plane_state *state = pipe->plane.state;
341 struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(state);
342 struct drm_framebuffer *fb = state->fb;
343 struct drm_rect rect;
344 int idx;
345
346 if (!pipe->crtc.state->active)
347 return;
348
349 if (WARN_ON(!fb))
350 return;
351
352 if (!drm_dev_enter(fb->dev, &idx))
353 return;
354
355 if (drm_atomic_helper_damage_merged(old_state, state, &rect))
356 mipi_dbi_fb_dirty(&shadow_plane_state->data[0], fb, &rect,
357 &shadow_plane_state->fmtcnv_state);
358
359 drm_dev_exit(idx);
360}
361EXPORT_SYMBOL(mipi_dbi_pipe_update);
362
363/**
364 * mipi_dbi_enable_flush - MIPI DBI enable helper
365 * @dbidev: MIPI DBI device structure
366 * @crtc_state: CRTC state
367 * @plane_state: Plane state
368 *
369 * Flushes the whole framebuffer and enables the backlight. Drivers can use this
370 * in their &drm_simple_display_pipe_funcs->enable callback.
371 *
372 * Note: Drivers which don't use mipi_dbi_pipe_update() because they have custom
373 * framebuffer flushing, can't use this function since they both use the same
374 * flushing code.
375 */
376void mipi_dbi_enable_flush(struct mipi_dbi_dev *dbidev,
377 struct drm_crtc_state *crtc_state,
378 struct drm_plane_state *plane_state)
379{
380 struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(plane_state);
381 struct drm_framebuffer *fb = plane_state->fb;
382 struct drm_rect rect = {
383 .x1 = 0,
384 .x2 = fb->width,
385 .y1 = 0,
386 .y2 = fb->height,
387 };
388 int idx;
389
390 if (!drm_dev_enter(&dbidev->drm, &idx))
391 return;
392
393 mipi_dbi_fb_dirty(&shadow_plane_state->data[0], fb, &rect,
394 &shadow_plane_state->fmtcnv_state);
395 backlight_enable(dbidev->backlight);
396
397 drm_dev_exit(idx);
398}
399EXPORT_SYMBOL(mipi_dbi_enable_flush);
400
401static void mipi_dbi_blank(struct mipi_dbi_dev *dbidev)
402{
403 struct drm_device *drm = &dbidev->drm;
404 u16 height = drm->mode_config.min_height;
405 u16 width = drm->mode_config.min_width;
406 struct mipi_dbi *dbi = &dbidev->dbi;
407 size_t len = width * height * 2;
408 int idx;
409
410 if (!drm_dev_enter(drm, &idx))
411 return;
412
413 memset(dbidev->tx_buf, 0, len);
414
415 mipi_dbi_set_window_address(dbidev, 0, width - 1, 0, height - 1);
416 mipi_dbi_command_buf(dbi, MIPI_DCS_WRITE_MEMORY_START,
417 (u8 *)dbidev->tx_buf, len);
418
419 drm_dev_exit(idx);
420}
421
422/**
423 * mipi_dbi_pipe_disable - MIPI DBI pipe disable helper
424 * @pipe: Display pipe
425 *
426 * This function disables backlight if present, if not the display memory is
427 * blanked. The regulator is disabled if in use. Drivers can use this as their
428 * &drm_simple_display_pipe_funcs->disable callback.
429 */
430void mipi_dbi_pipe_disable(struct drm_simple_display_pipe *pipe)
431{
432 struct mipi_dbi_dev *dbidev = drm_to_mipi_dbi_dev(pipe->crtc.dev);
433
434 DRM_DEBUG_KMS("\n");
435
436 if (dbidev->backlight)
437 backlight_disable(dbidev->backlight);
438 else
439 mipi_dbi_blank(dbidev);
440
441 if (dbidev->regulator)
442 regulator_disable(dbidev->regulator);
443 if (dbidev->io_regulator)
444 regulator_disable(dbidev->io_regulator);
445}
446EXPORT_SYMBOL(mipi_dbi_pipe_disable);
447
448/**
449 * mipi_dbi_pipe_begin_fb_access - MIPI DBI pipe begin-access helper
450 * @pipe: Display pipe
451 * @plane_state: Plane state
452 *
453 * This function implements struct &drm_simple_display_funcs.begin_fb_access.
454 *
455 * See drm_gem_begin_shadow_fb_access() for details and mipi_dbi_pipe_cleanup_fb()
456 * for cleanup.
457 *
458 * Returns:
459 * 0 on success, or a negative errno code otherwise.
460 */
461int mipi_dbi_pipe_begin_fb_access(struct drm_simple_display_pipe *pipe,
462 struct drm_plane_state *plane_state)
463{
464 return drm_gem_begin_shadow_fb_access(&pipe->plane, plane_state);
465}
466EXPORT_SYMBOL(mipi_dbi_pipe_begin_fb_access);
467
468/**
469 * mipi_dbi_pipe_end_fb_access - MIPI DBI pipe end-access helper
470 * @pipe: Display pipe
471 * @plane_state: Plane state
472 *
473 * This function implements struct &drm_simple_display_funcs.end_fb_access.
474 *
475 * See mipi_dbi_pipe_begin_fb_access().
476 */
477void mipi_dbi_pipe_end_fb_access(struct drm_simple_display_pipe *pipe,
478 struct drm_plane_state *plane_state)
479{
480 drm_gem_end_shadow_fb_access(&pipe->plane, plane_state);
481}
482EXPORT_SYMBOL(mipi_dbi_pipe_end_fb_access);
483
484/**
485 * mipi_dbi_pipe_reset_plane - MIPI DBI plane-reset helper
486 * @pipe: Display pipe
487 *
488 * This function implements struct &drm_simple_display_funcs.reset_plane
489 * for MIPI DBI planes.
490 */
491void mipi_dbi_pipe_reset_plane(struct drm_simple_display_pipe *pipe)
492{
493 drm_gem_reset_shadow_plane(&pipe->plane);
494}
495EXPORT_SYMBOL(mipi_dbi_pipe_reset_plane);
496
497/**
498 * mipi_dbi_pipe_duplicate_plane_state - duplicates MIPI DBI plane state
499 * @pipe: Display pipe
500 *
501 * This function implements struct &drm_simple_display_funcs.duplicate_plane_state
502 * for MIPI DBI planes.
503 *
504 * See drm_gem_duplicate_shadow_plane_state() for additional details.
505 *
506 * Returns:
507 * A pointer to a new plane state on success, or NULL otherwise.
508 */
509struct drm_plane_state *mipi_dbi_pipe_duplicate_plane_state(struct drm_simple_display_pipe *pipe)
510{
511 return drm_gem_duplicate_shadow_plane_state(&pipe->plane);
512}
513EXPORT_SYMBOL(mipi_dbi_pipe_duplicate_plane_state);
514
515/**
516 * mipi_dbi_pipe_destroy_plane_state - cleans up MIPI DBI plane state
517 * @pipe: Display pipe
518 * @plane_state: Plane state
519 *
520 * This function implements struct drm_simple_display_funcs.destroy_plane_state
521 * for MIPI DBI planes.
522 *
523 * See drm_gem_destroy_shadow_plane_state() for additional details.
524 */
525void mipi_dbi_pipe_destroy_plane_state(struct drm_simple_display_pipe *pipe,
526 struct drm_plane_state *plane_state)
527{
528 drm_gem_destroy_shadow_plane_state(&pipe->plane, plane_state);
529}
530EXPORT_SYMBOL(mipi_dbi_pipe_destroy_plane_state);
531
532static int mipi_dbi_connector_get_modes(struct drm_connector *connector)
533{
534 struct mipi_dbi_dev *dbidev = drm_to_mipi_dbi_dev(connector->dev);
535
536 return drm_connector_helper_get_modes_fixed(connector, &dbidev->mode);
537}
538
539static const struct drm_connector_helper_funcs mipi_dbi_connector_hfuncs = {
540 .get_modes = mipi_dbi_connector_get_modes,
541};
542
543static const struct drm_connector_funcs mipi_dbi_connector_funcs = {
544 .reset = drm_atomic_helper_connector_reset,
545 .fill_modes = drm_helper_probe_single_connector_modes,
546 .destroy = drm_connector_cleanup,
547 .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
548 .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
549};
550
551static int mipi_dbi_rotate_mode(struct drm_display_mode *mode,
552 unsigned int rotation)
553{
554 if (rotation == 0 || rotation == 180) {
555 return 0;
556 } else if (rotation == 90 || rotation == 270) {
557 swap(mode->hdisplay, mode->vdisplay);
558 swap(mode->hsync_start, mode->vsync_start);
559 swap(mode->hsync_end, mode->vsync_end);
560 swap(mode->htotal, mode->vtotal);
561 swap(mode->width_mm, mode->height_mm);
562 return 0;
563 } else {
564 return -EINVAL;
565 }
566}
567
568static const struct drm_mode_config_funcs mipi_dbi_mode_config_funcs = {
569 .fb_create = drm_gem_fb_create_with_dirty,
570 .atomic_check = drm_atomic_helper_check,
571 .atomic_commit = drm_atomic_helper_commit,
572};
573
574static const uint32_t mipi_dbi_formats[] = {
575 DRM_FORMAT_RGB565,
576 DRM_FORMAT_XRGB8888,
577};
578
579/**
580 * mipi_dbi_dev_init_with_formats - MIPI DBI device initialization with custom formats
581 * @dbidev: MIPI DBI device structure to initialize
582 * @funcs: Display pipe functions
583 * @formats: Array of supported formats (DRM_FORMAT\_\*).
584 * @format_count: Number of elements in @formats
585 * @mode: Display mode
586 * @rotation: Initial rotation in degrees Counter Clock Wise
587 * @tx_buf_size: Allocate a transmit buffer of this size.
588 *
589 * This function sets up a &drm_simple_display_pipe with a &drm_connector that
590 * has one fixed &drm_display_mode which is rotated according to @rotation.
591 * This mode is used to set the mode config min/max width/height properties.
592 *
593 * Use mipi_dbi_dev_init() if you want native RGB565 and emulated XRGB8888 format.
594 *
595 * Note:
596 * Some of the helper functions expects RGB565 to be the default format and the
597 * transmit buffer sized to fit that.
598 *
599 * Returns:
600 * Zero on success, negative error code on failure.
601 */
602int mipi_dbi_dev_init_with_formats(struct mipi_dbi_dev *dbidev,
603 const struct drm_simple_display_pipe_funcs *funcs,
604 const uint32_t *formats, unsigned int format_count,
605 const struct drm_display_mode *mode,
606 unsigned int rotation, size_t tx_buf_size)
607{
608 static const uint64_t modifiers[] = {
609 DRM_FORMAT_MOD_LINEAR,
610 DRM_FORMAT_MOD_INVALID
611 };
612 struct drm_device *drm = &dbidev->drm;
613 int ret;
614
615 if (!dbidev->dbi.command)
616 return -EINVAL;
617
618 ret = drmm_mode_config_init(drm);
619 if (ret)
620 return ret;
621
622 dbidev->tx_buf = devm_kmalloc(drm->dev, tx_buf_size, GFP_KERNEL);
623 if (!dbidev->tx_buf)
624 return -ENOMEM;
625
626 drm_mode_copy(&dbidev->mode, mode);
627 ret = mipi_dbi_rotate_mode(&dbidev->mode, rotation);
628 if (ret) {
629 DRM_ERROR("Illegal rotation value %u\n", rotation);
630 return -EINVAL;
631 }
632
633 drm_connector_helper_add(&dbidev->connector, &mipi_dbi_connector_hfuncs);
634 ret = drm_connector_init(drm, &dbidev->connector, &mipi_dbi_connector_funcs,
635 DRM_MODE_CONNECTOR_SPI);
636 if (ret)
637 return ret;
638
639 ret = drm_simple_display_pipe_init(drm, &dbidev->pipe, funcs, formats, format_count,
640 modifiers, &dbidev->connector);
641 if (ret)
642 return ret;
643
644 drm_plane_enable_fb_damage_clips(&dbidev->pipe.plane);
645
646 drm->mode_config.funcs = &mipi_dbi_mode_config_funcs;
647 drm->mode_config.min_width = dbidev->mode.hdisplay;
648 drm->mode_config.max_width = dbidev->mode.hdisplay;
649 drm->mode_config.min_height = dbidev->mode.vdisplay;
650 drm->mode_config.max_height = dbidev->mode.vdisplay;
651 dbidev->rotation = rotation;
652 dbidev->pixel_format = formats[0];
653 if (formats[0] == DRM_FORMAT_RGB888)
654 dbidev->dbi.write_memory_bpw = 8;
655
656 DRM_DEBUG_KMS("rotation = %u\n", rotation);
657
658 return 0;
659}
660EXPORT_SYMBOL(mipi_dbi_dev_init_with_formats);
661
662/**
663 * mipi_dbi_dev_init - MIPI DBI device initialization
664 * @dbidev: MIPI DBI device structure to initialize
665 * @funcs: Display pipe functions
666 * @mode: Display mode
667 * @rotation: Initial rotation in degrees Counter Clock Wise
668 *
669 * This function sets up a &drm_simple_display_pipe with a &drm_connector that
670 * has one fixed &drm_display_mode which is rotated according to @rotation.
671 * This mode is used to set the mode config min/max width/height properties.
672 * Additionally &mipi_dbi.tx_buf is allocated.
673 *
674 * Supported formats: Native RGB565 and emulated XRGB8888.
675 *
676 * Returns:
677 * Zero on success, negative error code on failure.
678 */
679int mipi_dbi_dev_init(struct mipi_dbi_dev *dbidev,
680 const struct drm_simple_display_pipe_funcs *funcs,
681 const struct drm_display_mode *mode, unsigned int rotation)
682{
683 size_t bufsize = mode->vdisplay * mode->hdisplay * sizeof(u16);
684
685 dbidev->drm.mode_config.preferred_depth = 16;
686
687 return mipi_dbi_dev_init_with_formats(dbidev, funcs, mipi_dbi_formats,
688 ARRAY_SIZE(mipi_dbi_formats), mode,
689 rotation, bufsize);
690}
691EXPORT_SYMBOL(mipi_dbi_dev_init);
692
693/**
694 * mipi_dbi_hw_reset - Hardware reset of controller
695 * @dbi: MIPI DBI structure
696 *
697 * Reset controller if the &mipi_dbi->reset gpio is set.
698 */
699void mipi_dbi_hw_reset(struct mipi_dbi *dbi)
700{
701 if (!dbi->reset)
702 return;
703
704 gpiod_set_value_cansleep(dbi->reset, 0);
705 usleep_range(20, 1000);
706 gpiod_set_value_cansleep(dbi->reset, 1);
707 msleep(120);
708}
709EXPORT_SYMBOL(mipi_dbi_hw_reset);
710
711/**
712 * mipi_dbi_display_is_on - Check if display is on
713 * @dbi: MIPI DBI structure
714 *
715 * This function checks the Power Mode register (if readable) to see if
716 * display output is turned on. This can be used to see if the bootloader
717 * has already turned on the display avoiding flicker when the pipeline is
718 * enabled.
719 *
720 * Returns:
721 * true if the display can be verified to be on, false otherwise.
722 */
723bool mipi_dbi_display_is_on(struct mipi_dbi *dbi)
724{
725 u8 val;
726
727 if (mipi_dbi_command_read(dbi, MIPI_DCS_GET_POWER_MODE, &val))
728 return false;
729
730 val &= ~DCS_POWER_MODE_RESERVED_MASK;
731
732 /* The poweron/reset value is 08h DCS_POWER_MODE_DISPLAY_NORMAL_MODE */
733 if (val != (DCS_POWER_MODE_DISPLAY |
734 DCS_POWER_MODE_DISPLAY_NORMAL_MODE | DCS_POWER_MODE_SLEEP_MODE))
735 return false;
736
737 DRM_DEBUG_DRIVER("Display is ON\n");
738
739 return true;
740}
741EXPORT_SYMBOL(mipi_dbi_display_is_on);
742
743static int mipi_dbi_poweron_reset_conditional(struct mipi_dbi_dev *dbidev, bool cond)
744{
745 struct device *dev = dbidev->drm.dev;
746 struct mipi_dbi *dbi = &dbidev->dbi;
747 int ret;
748
749 if (dbidev->regulator) {
750 ret = regulator_enable(dbidev->regulator);
751 if (ret) {
752 DRM_DEV_ERROR(dev, "Failed to enable regulator (%d)\n", ret);
753 return ret;
754 }
755 }
756
757 if (dbidev->io_regulator) {
758 ret = regulator_enable(dbidev->io_regulator);
759 if (ret) {
760 DRM_DEV_ERROR(dev, "Failed to enable I/O regulator (%d)\n", ret);
761 if (dbidev->regulator)
762 regulator_disable(dbidev->regulator);
763 return ret;
764 }
765 }
766
767 if (cond && mipi_dbi_display_is_on(dbi))
768 return 1;
769
770 mipi_dbi_hw_reset(dbi);
771 ret = mipi_dbi_command(dbi, MIPI_DCS_SOFT_RESET);
772 if (ret) {
773 DRM_DEV_ERROR(dev, "Failed to send reset command (%d)\n", ret);
774 if (dbidev->regulator)
775 regulator_disable(dbidev->regulator);
776 if (dbidev->io_regulator)
777 regulator_disable(dbidev->io_regulator);
778 return ret;
779 }
780
781 /*
782 * If we did a hw reset, we know the controller is in Sleep mode and
783 * per MIPI DSC spec should wait 5ms after soft reset. If we didn't,
784 * we assume worst case and wait 120ms.
785 */
786 if (dbi->reset)
787 usleep_range(5000, 20000);
788 else
789 msleep(120);
790
791 return 0;
792}
793
794/**
795 * mipi_dbi_poweron_reset - MIPI DBI poweron and reset
796 * @dbidev: MIPI DBI device structure
797 *
798 * This function enables the regulator if used and does a hardware and software
799 * reset.
800 *
801 * Returns:
802 * Zero on success, or a negative error code.
803 */
804int mipi_dbi_poweron_reset(struct mipi_dbi_dev *dbidev)
805{
806 return mipi_dbi_poweron_reset_conditional(dbidev, false);
807}
808EXPORT_SYMBOL(mipi_dbi_poweron_reset);
809
810/**
811 * mipi_dbi_poweron_conditional_reset - MIPI DBI poweron and conditional reset
812 * @dbidev: MIPI DBI device structure
813 *
814 * This function enables the regulator if used and if the display is off, it
815 * does a hardware and software reset. If mipi_dbi_display_is_on() determines
816 * that the display is on, no reset is performed.
817 *
818 * Returns:
819 * Zero if the controller was reset, 1 if the display was already on, or a
820 * negative error code.
821 */
822int mipi_dbi_poweron_conditional_reset(struct mipi_dbi_dev *dbidev)
823{
824 return mipi_dbi_poweron_reset_conditional(dbidev, true);
825}
826EXPORT_SYMBOL(mipi_dbi_poweron_conditional_reset);
827
828#if IS_ENABLED(CONFIG_SPI)
829
830/**
831 * mipi_dbi_spi_cmd_max_speed - get the maximum SPI bus speed
832 * @spi: SPI device
833 * @len: The transfer buffer length.
834 *
835 * Many controllers have a max speed of 10MHz, but can be pushed way beyond
836 * that. Increase reliability by running pixel data at max speed and the rest
837 * at 10MHz, preventing transfer glitches from messing up the init settings.
838 */
839u32 mipi_dbi_spi_cmd_max_speed(struct spi_device *spi, size_t len)
840{
841 if (len > 64)
842 return 0; /* use default */
843
844 return min_t(u32, 10000000, spi->max_speed_hz);
845}
846EXPORT_SYMBOL(mipi_dbi_spi_cmd_max_speed);
847
848/*
849 * MIPI DBI Type C Option 1
850 *
851 * If the SPI controller doesn't have 9 bits per word support,
852 * use blocks of 9 bytes to send 8x 9-bit words using a 8-bit SPI transfer.
853 * Pad partial blocks with MIPI_DCS_NOP (zero).
854 * This is how the D/C bit (x) is added:
855 * x7654321
856 * 0x765432
857 * 10x76543
858 * 210x7654
859 * 3210x765
860 * 43210x76
861 * 543210x7
862 * 6543210x
863 * 76543210
864 */
865
866static int mipi_dbi_spi1e_transfer(struct mipi_dbi *dbi, int dc,
867 const void *buf, size_t len,
868 unsigned int bpw)
869{
870 bool swap_bytes = (bpw == 16);
871 size_t chunk, max_chunk = dbi->tx_buf9_len;
872 struct spi_device *spi = dbi->spi;
873 struct spi_transfer tr = {
874 .tx_buf = dbi->tx_buf9,
875 .bits_per_word = 8,
876 };
877 struct spi_message m;
878 const u8 *src = buf;
879 int i, ret;
880 u8 *dst;
881
882 if (drm_debug_enabled(DRM_UT_DRIVER))
883 pr_debug("[drm:%s] dc=%d, max_chunk=%zu, transfers:\n",
884 __func__, dc, max_chunk);
885
886 tr.speed_hz = mipi_dbi_spi_cmd_max_speed(spi, len);
887 spi_message_init_with_transfers(&m, &tr, 1);
888
889 if (!dc) {
890 if (WARN_ON_ONCE(len != 1))
891 return -EINVAL;
892
893 /* Command: pad no-op's (zeroes) at beginning of block */
894 dst = dbi->tx_buf9;
895 memset(dst, 0, 9);
896 dst[8] = *src;
897 tr.len = 9;
898
899 return spi_sync(spi, &m);
900 }
901
902 /* max with room for adding one bit per byte */
903 max_chunk = max_chunk / 9 * 8;
904 /* but no bigger than len */
905 max_chunk = min(max_chunk, len);
906 /* 8 byte blocks */
907 max_chunk = max_t(size_t, 8, max_chunk & ~0x7);
908
909 while (len) {
910 size_t added = 0;
911
912 chunk = min(len, max_chunk);
913 len -= chunk;
914 dst = dbi->tx_buf9;
915
916 if (chunk < 8) {
917 u8 val, carry = 0;
918
919 /* Data: pad no-op's (zeroes) at end of block */
920 memset(dst, 0, 9);
921
922 if (swap_bytes) {
923 for (i = 1; i < (chunk + 1); i++) {
924 val = src[1];
925 *dst++ = carry | BIT(8 - i) | (val >> i);
926 carry = val << (8 - i);
927 i++;
928 val = src[0];
929 *dst++ = carry | BIT(8 - i) | (val >> i);
930 carry = val << (8 - i);
931 src += 2;
932 }
933 *dst++ = carry;
934 } else {
935 for (i = 1; i < (chunk + 1); i++) {
936 val = *src++;
937 *dst++ = carry | BIT(8 - i) | (val >> i);
938 carry = val << (8 - i);
939 }
940 *dst++ = carry;
941 }
942
943 chunk = 8;
944 added = 1;
945 } else {
946 for (i = 0; i < chunk; i += 8) {
947 if (swap_bytes) {
948 *dst++ = BIT(7) | (src[1] >> 1);
949 *dst++ = (src[1] << 7) | BIT(6) | (src[0] >> 2);
950 *dst++ = (src[0] << 6) | BIT(5) | (src[3] >> 3);
951 *dst++ = (src[3] << 5) | BIT(4) | (src[2] >> 4);
952 *dst++ = (src[2] << 4) | BIT(3) | (src[5] >> 5);
953 *dst++ = (src[5] << 3) | BIT(2) | (src[4] >> 6);
954 *dst++ = (src[4] << 2) | BIT(1) | (src[7] >> 7);
955 *dst++ = (src[7] << 1) | BIT(0);
956 *dst++ = src[6];
957 } else {
958 *dst++ = BIT(7) | (src[0] >> 1);
959 *dst++ = (src[0] << 7) | BIT(6) | (src[1] >> 2);
960 *dst++ = (src[1] << 6) | BIT(5) | (src[2] >> 3);
961 *dst++ = (src[2] << 5) | BIT(4) | (src[3] >> 4);
962 *dst++ = (src[3] << 4) | BIT(3) | (src[4] >> 5);
963 *dst++ = (src[4] << 3) | BIT(2) | (src[5] >> 6);
964 *dst++ = (src[5] << 2) | BIT(1) | (src[6] >> 7);
965 *dst++ = (src[6] << 1) | BIT(0);
966 *dst++ = src[7];
967 }
968
969 src += 8;
970 added++;
971 }
972 }
973
974 tr.len = chunk + added;
975
976 ret = spi_sync(spi, &m);
977 if (ret)
978 return ret;
979 }
980
981 return 0;
982}
983
984static int mipi_dbi_spi1_transfer(struct mipi_dbi *dbi, int dc,
985 const void *buf, size_t len,
986 unsigned int bpw)
987{
988 struct spi_device *spi = dbi->spi;
989 struct spi_transfer tr = {
990 .bits_per_word = 9,
991 };
992 const u16 *src16 = buf;
993 const u8 *src8 = buf;
994 struct spi_message m;
995 size_t max_chunk;
996 u16 *dst16;
997 int ret;
998
999 if (!spi_is_bpw_supported(spi, 9))
1000 return mipi_dbi_spi1e_transfer(dbi, dc, buf, len, bpw);
1001
1002 tr.speed_hz = mipi_dbi_spi_cmd_max_speed(spi, len);
1003 max_chunk = dbi->tx_buf9_len;
1004 dst16 = dbi->tx_buf9;
1005
1006 if (drm_debug_enabled(DRM_UT_DRIVER))
1007 pr_debug("[drm:%s] dc=%d, max_chunk=%zu, transfers:\n",
1008 __func__, dc, max_chunk);
1009
1010 max_chunk = min(max_chunk / 2, len);
1011
1012 spi_message_init_with_transfers(&m, &tr, 1);
1013 tr.tx_buf = dst16;
1014
1015 while (len) {
1016 size_t chunk = min(len, max_chunk);
1017 unsigned int i;
1018
1019 if (bpw == 16) {
1020 for (i = 0; i < (chunk * 2); i += 2) {
1021 dst16[i] = *src16 >> 8;
1022 dst16[i + 1] = *src16++ & 0xFF;
1023 if (dc) {
1024 dst16[i] |= 0x0100;
1025 dst16[i + 1] |= 0x0100;
1026 }
1027 }
1028 } else {
1029 for (i = 0; i < chunk; i++) {
1030 dst16[i] = *src8++;
1031 if (dc)
1032 dst16[i] |= 0x0100;
1033 }
1034 }
1035
1036 tr.len = chunk * 2;
1037 len -= chunk;
1038
1039 ret = spi_sync(spi, &m);
1040 if (ret)
1041 return ret;
1042 }
1043
1044 return 0;
1045}
1046
1047static int mipi_dbi_typec1_command_read(struct mipi_dbi *dbi, u8 *cmd,
1048 u8 *data, size_t len)
1049{
1050 struct spi_device *spi = dbi->spi;
1051 u32 speed_hz = min_t(u32, MIPI_DBI_MAX_SPI_READ_SPEED,
1052 spi->max_speed_hz / 2);
1053 struct spi_transfer tr[2] = {
1054 {
1055 .speed_hz = speed_hz,
1056 .bits_per_word = 9,
1057 .tx_buf = dbi->tx_buf9,
1058 .len = 2,
1059 }, {
1060 .speed_hz = speed_hz,
1061 .bits_per_word = 8,
1062 .len = len,
1063 .rx_buf = data,
1064 },
1065 };
1066 struct spi_message m;
1067 u16 *dst16;
1068 int ret;
1069
1070 if (!len)
1071 return -EINVAL;
1072
1073 if (!spi_is_bpw_supported(spi, 9)) {
1074 /*
1075 * FIXME: implement something like mipi_dbi_spi1e_transfer() but
1076 * for reads using emulation.
1077 */
1078 dev_err(&spi->dev,
1079 "reading on host not supporting 9 bpw not yet implemented\n");
1080 return -EOPNOTSUPP;
1081 }
1082
1083 /*
1084 * Turn the 8bit command into a 16bit version of the command in the
1085 * buffer. Only 9 bits of this will be used when executing the actual
1086 * transfer.
1087 */
1088 dst16 = dbi->tx_buf9;
1089 dst16[0] = *cmd;
1090
1091 spi_message_init_with_transfers(&m, tr, ARRAY_SIZE(tr));
1092 ret = spi_sync(spi, &m);
1093
1094 if (!ret)
1095 MIPI_DBI_DEBUG_COMMAND(*cmd, data, len);
1096
1097 return ret;
1098}
1099
1100static int mipi_dbi_typec1_command(struct mipi_dbi *dbi, u8 *cmd,
1101 u8 *parameters, size_t num)
1102{
1103 unsigned int bpw = 8;
1104 int ret;
1105
1106 if (mipi_dbi_command_is_read(dbi, *cmd))
1107 return mipi_dbi_typec1_command_read(dbi, cmd, parameters, num);
1108
1109 MIPI_DBI_DEBUG_COMMAND(*cmd, parameters, num);
1110
1111 ret = mipi_dbi_spi1_transfer(dbi, 0, cmd, 1, 8);
1112 if (ret || !num)
1113 return ret;
1114
1115 if (*cmd == MIPI_DCS_WRITE_MEMORY_START)
1116 bpw = dbi->write_memory_bpw;
1117
1118 return mipi_dbi_spi1_transfer(dbi, 1, parameters, num, bpw);
1119}
1120
1121/* MIPI DBI Type C Option 3 */
1122
1123static int mipi_dbi_typec3_command_read(struct mipi_dbi *dbi, u8 *cmd,
1124 u8 *data, size_t len)
1125{
1126 struct spi_device *spi = dbi->spi;
1127 u32 speed_hz = min_t(u32, MIPI_DBI_MAX_SPI_READ_SPEED,
1128 spi->max_speed_hz / 2);
1129 struct spi_transfer tr[2] = {
1130 {
1131 .speed_hz = speed_hz,
1132 .tx_buf = cmd,
1133 .len = 1,
1134 }, {
1135 .speed_hz = speed_hz,
1136 .len = len,
1137 },
1138 };
1139 struct spi_message m;
1140 u8 *buf;
1141 int ret;
1142
1143 if (!len)
1144 return -EINVAL;
1145
1146 /*
1147 * Support non-standard 24-bit and 32-bit Nokia read commands which
1148 * start with a dummy clock, so we need to read an extra byte.
1149 */
1150 if (*cmd == MIPI_DCS_GET_DISPLAY_ID ||
1151 *cmd == MIPI_DCS_GET_DISPLAY_STATUS) {
1152 if (!(len == 3 || len == 4))
1153 return -EINVAL;
1154
1155 tr[1].len = len + 1;
1156 }
1157
1158 buf = kmalloc(tr[1].len, GFP_KERNEL);
1159 if (!buf)
1160 return -ENOMEM;
1161
1162 tr[1].rx_buf = buf;
1163
1164 spi_bus_lock(spi->controller);
1165 gpiod_set_value_cansleep(dbi->dc, 0);
1166
1167 spi_message_init_with_transfers(&m, tr, ARRAY_SIZE(tr));
1168 ret = spi_sync_locked(spi, &m);
1169 spi_bus_unlock(spi->controller);
1170 if (ret)
1171 goto err_free;
1172
1173 if (tr[1].len == len) {
1174 memcpy(data, buf, len);
1175 } else {
1176 unsigned int i;
1177
1178 for (i = 0; i < len; i++)
1179 data[i] = (buf[i] << 1) | (buf[i + 1] >> 7);
1180 }
1181
1182 MIPI_DBI_DEBUG_COMMAND(*cmd, data, len);
1183
1184err_free:
1185 kfree(buf);
1186
1187 return ret;
1188}
1189
1190static int mipi_dbi_typec3_command(struct mipi_dbi *dbi, u8 *cmd,
1191 u8 *par, size_t num)
1192{
1193 struct spi_device *spi = dbi->spi;
1194 unsigned int bpw = 8;
1195 u32 speed_hz;
1196 int ret;
1197
1198 if (mipi_dbi_command_is_read(dbi, *cmd))
1199 return mipi_dbi_typec3_command_read(dbi, cmd, par, num);
1200
1201 MIPI_DBI_DEBUG_COMMAND(*cmd, par, num);
1202
1203 spi_bus_lock(spi->controller);
1204 gpiod_set_value_cansleep(dbi->dc, 0);
1205 speed_hz = mipi_dbi_spi_cmd_max_speed(spi, 1);
1206 ret = mipi_dbi_spi_transfer(spi, speed_hz, 8, cmd, 1);
1207 spi_bus_unlock(spi->controller);
1208 if (ret || !num)
1209 return ret;
1210
1211 if (*cmd == MIPI_DCS_WRITE_MEMORY_START)
1212 bpw = dbi->write_memory_bpw;
1213
1214 spi_bus_lock(spi->controller);
1215 gpiod_set_value_cansleep(dbi->dc, 1);
1216 speed_hz = mipi_dbi_spi_cmd_max_speed(spi, num);
1217 ret = mipi_dbi_spi_transfer(spi, speed_hz, bpw, par, num);
1218 spi_bus_unlock(spi->controller);
1219
1220 return ret;
1221}
1222
1223/**
1224 * mipi_dbi_spi_init - Initialize MIPI DBI SPI interface
1225 * @spi: SPI device
1226 * @dbi: MIPI DBI structure to initialize
1227 * @dc: D/C gpio (optional)
1228 *
1229 * This function sets &mipi_dbi->command, enables &mipi_dbi->read_commands for the
1230 * usual read commands. It should be followed by a call to mipi_dbi_dev_init() or
1231 * a driver-specific init.
1232 *
1233 * If @dc is set, a Type C Option 3 interface is assumed, if not
1234 * Type C Option 1.
1235 *
1236 * If the command is %MIPI_DCS_WRITE_MEMORY_START and the pixel format is RGB565, endianness has
1237 * to be taken into account. The MIPI DBI serial interface is big endian and framebuffers are
1238 * assumed stored in memory as little endian (%DRM_FORMAT_BIG_ENDIAN is not supported).
1239 *
1240 * This is how endianness is handled:
1241 *
1242 * Option 1 (D/C as a bit): The buffer is sent on the wire byte by byte so the 16-bit buffer is
1243 * byteswapped before transfer.
1244 *
1245 * Option 3 (D/C as a gpio): If the SPI controller supports 16 bits per word the buffer can be
1246 * sent as-is. If not the caller is responsible for swapping the bytes
1247 * before calling mipi_dbi_command_buf() and the buffer is sent 8 bpw.
1248 *
1249 * This handling is optimised for %DRM_FORMAT_RGB565 framebuffers.
1250 *
1251 * If the interface is Option 1 and the SPI controller doesn't support 9 bits per word,
1252 * the buffer is sent as 9x 8-bit words, padded with MIPI DCS no-op commands if necessary.
1253 *
1254 * Returns:
1255 * Zero on success, negative error code on failure.
1256 */
1257int mipi_dbi_spi_init(struct spi_device *spi, struct mipi_dbi *dbi,
1258 struct gpio_desc *dc)
1259{
1260 struct device *dev = &spi->dev;
1261 int ret;
1262
1263 /*
1264 * Even though it's not the SPI device that does DMA (the master does),
1265 * the dma mask is necessary for the dma_alloc_wc() in the GEM code
1266 * (e.g., drm_gem_dma_create()). The dma_addr returned will be a physical
1267 * address which might be different from the bus address, but this is
1268 * not a problem since the address will not be used.
1269 * The virtual address is used in the transfer and the SPI core
1270 * re-maps it on the SPI master device using the DMA streaming API
1271 * (spi_map_buf()).
1272 */
1273 if (!dev->coherent_dma_mask) {
1274 ret = dma_coerce_mask_and_coherent(dev, DMA_BIT_MASK(32));
1275 if (ret) {
1276 dev_warn(dev, "Failed to set dma mask %d\n", ret);
1277 return ret;
1278 }
1279 }
1280
1281 dbi->spi = spi;
1282 dbi->read_commands = mipi_dbi_dcs_read_commands;
1283 dbi->write_memory_bpw = 16;
1284
1285 if (dc) {
1286 dbi->command = mipi_dbi_typec3_command;
1287 dbi->dc = dc;
1288 if (!spi_is_bpw_supported(spi, 16)) {
1289 dbi->write_memory_bpw = 8;
1290 dbi->swap_bytes = true;
1291 }
1292 } else {
1293 dbi->command = mipi_dbi_typec1_command;
1294 dbi->tx_buf9_len = SZ_16K;
1295 dbi->tx_buf9 = devm_kmalloc(dev, dbi->tx_buf9_len, GFP_KERNEL);
1296 if (!dbi->tx_buf9)
1297 return -ENOMEM;
1298 }
1299
1300 mutex_init(&dbi->cmdlock);
1301
1302 DRM_DEBUG_DRIVER("SPI speed: %uMHz\n", spi->max_speed_hz / 1000000);
1303
1304 return 0;
1305}
1306EXPORT_SYMBOL(mipi_dbi_spi_init);
1307
1308/**
1309 * mipi_dbi_spi_transfer - SPI transfer helper
1310 * @spi: SPI device
1311 * @speed_hz: Override speed (optional)
1312 * @bpw: Bits per word
1313 * @buf: Buffer to transfer
1314 * @len: Buffer length
1315 *
1316 * This SPI transfer helper breaks up the transfer of @buf into chunks which
1317 * the SPI controller driver can handle. The SPI bus must be locked when
1318 * calling this.
1319 *
1320 * Returns:
1321 * Zero on success, negative error code on failure.
1322 */
1323int mipi_dbi_spi_transfer(struct spi_device *spi, u32 speed_hz,
1324 u8 bpw, const void *buf, size_t len)
1325{
1326 size_t max_chunk = spi_max_transfer_size(spi);
1327 struct spi_transfer tr = {
1328 .bits_per_word = bpw,
1329 .speed_hz = speed_hz,
1330 };
1331 struct spi_message m;
1332 size_t chunk;
1333 int ret;
1334
1335 /* In __spi_validate, there's a validation that no partial transfers
1336 * are accepted (xfer->len % w_size must be zero).
1337 * Here we align max_chunk to multiple of 2 (16bits),
1338 * to prevent transfers from being rejected.
1339 */
1340 max_chunk = ALIGN_DOWN(max_chunk, 2);
1341
1342 spi_message_init_with_transfers(&m, &tr, 1);
1343
1344 while (len) {
1345 chunk = min(len, max_chunk);
1346
1347 tr.tx_buf = buf;
1348 tr.len = chunk;
1349 buf += chunk;
1350 len -= chunk;
1351
1352 ret = spi_sync_locked(spi, &m);
1353 if (ret)
1354 return ret;
1355 }
1356
1357 return 0;
1358}
1359EXPORT_SYMBOL(mipi_dbi_spi_transfer);
1360
1361#endif /* CONFIG_SPI */
1362
1363#ifdef CONFIG_DEBUG_FS
1364
1365static ssize_t mipi_dbi_debugfs_command_write(struct file *file,
1366 const char __user *ubuf,
1367 size_t count, loff_t *ppos)
1368{
1369 struct seq_file *m = file->private_data;
1370 struct mipi_dbi_dev *dbidev = m->private;
1371 u8 val, cmd = 0, parameters[64];
1372 char *buf, *pos, *token;
1373 int i, ret, idx;
1374
1375 if (!drm_dev_enter(&dbidev->drm, &idx))
1376 return -ENODEV;
1377
1378 buf = memdup_user_nul(ubuf, count);
1379 if (IS_ERR(buf)) {
1380 ret = PTR_ERR(buf);
1381 goto err_exit;
1382 }
1383
1384 /* strip trailing whitespace */
1385 for (i = count - 1; i > 0; i--)
1386 if (isspace(buf[i]))
1387 buf[i] = '\0';
1388 else
1389 break;
1390 i = 0;
1391 pos = buf;
1392 while (pos) {
1393 token = strsep(&pos, " ");
1394 if (!token) {
1395 ret = -EINVAL;
1396 goto err_free;
1397 }
1398
1399 ret = kstrtou8(token, 16, &val);
1400 if (ret < 0)
1401 goto err_free;
1402
1403 if (token == buf)
1404 cmd = val;
1405 else
1406 parameters[i++] = val;
1407
1408 if (i == 64) {
1409 ret = -E2BIG;
1410 goto err_free;
1411 }
1412 }
1413
1414 ret = mipi_dbi_command_buf(&dbidev->dbi, cmd, parameters, i);
1415
1416err_free:
1417 kfree(buf);
1418err_exit:
1419 drm_dev_exit(idx);
1420
1421 return ret < 0 ? ret : count;
1422}
1423
1424static int mipi_dbi_debugfs_command_show(struct seq_file *m, void *unused)
1425{
1426 struct mipi_dbi_dev *dbidev = m->private;
1427 struct mipi_dbi *dbi = &dbidev->dbi;
1428 u8 cmd, val[4];
1429 int ret, idx;
1430 size_t len;
1431
1432 if (!drm_dev_enter(&dbidev->drm, &idx))
1433 return -ENODEV;
1434
1435 for (cmd = 0; cmd < 255; cmd++) {
1436 if (!mipi_dbi_command_is_read(dbi, cmd))
1437 continue;
1438
1439 switch (cmd) {
1440 case MIPI_DCS_READ_MEMORY_START:
1441 case MIPI_DCS_READ_MEMORY_CONTINUE:
1442 len = 2;
1443 break;
1444 case MIPI_DCS_GET_DISPLAY_ID:
1445 len = 3;
1446 break;
1447 case MIPI_DCS_GET_DISPLAY_STATUS:
1448 len = 4;
1449 break;
1450 default:
1451 len = 1;
1452 break;
1453 }
1454
1455 seq_printf(m, "%02x: ", cmd);
1456 ret = mipi_dbi_command_buf(dbi, cmd, val, len);
1457 if (ret) {
1458 seq_puts(m, "XX\n");
1459 continue;
1460 }
1461 seq_printf(m, "%*phN\n", (int)len, val);
1462 }
1463
1464 drm_dev_exit(idx);
1465
1466 return 0;
1467}
1468
1469static int mipi_dbi_debugfs_command_open(struct inode *inode,
1470 struct file *file)
1471{
1472 return single_open(file, mipi_dbi_debugfs_command_show,
1473 inode->i_private);
1474}
1475
1476static const struct file_operations mipi_dbi_debugfs_command_fops = {
1477 .owner = THIS_MODULE,
1478 .open = mipi_dbi_debugfs_command_open,
1479 .read = seq_read,
1480 .llseek = seq_lseek,
1481 .release = single_release,
1482 .write = mipi_dbi_debugfs_command_write,
1483};
1484
1485/**
1486 * mipi_dbi_debugfs_init - Create debugfs entries
1487 * @minor: DRM minor
1488 *
1489 * This function creates a 'command' debugfs file for sending commands to the
1490 * controller or getting the read command values.
1491 * Drivers can use this as their &drm_driver->debugfs_init callback.
1492 *
1493 */
1494void mipi_dbi_debugfs_init(struct drm_minor *minor)
1495{
1496 struct mipi_dbi_dev *dbidev = drm_to_mipi_dbi_dev(minor->dev);
1497 umode_t mode = S_IFREG | S_IWUSR;
1498
1499 if (dbidev->dbi.read_commands)
1500 mode |= S_IRUGO;
1501 debugfs_create_file("command", mode, minor->debugfs_root, dbidev,
1502 &mipi_dbi_debugfs_command_fops);
1503}
1504EXPORT_SYMBOL(mipi_dbi_debugfs_init);
1505
1506#endif
1507
1508MODULE_DESCRIPTION("MIPI Display Bus Interface (DBI) LCD controller support");
1509MODULE_LICENSE("GPL");