1 // SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
2
3 #include <drm/clients/drm_client_setup.h>
4 #include <drm/drm_atomic.h>
5 #include <drm/drm_atomic_helper.h>
6 #include <drm/drm_connector.h>
7 #include <drm/drm_damage_helper.h>
8 #include <drm/drm_drv.h>
9 #include <drm/drm_fb_dma_helper.h>
10 #include <drm/drm_fbdev_dma.h>
11 #include <drm/drm_format_helper.h>
12 #include <drm/drm_framebuffer.h>
13 #include <drm/drm_gem_atomic_helper.h>
14 #include <drm/drm_gem_dma_helper.h>
15 #include <drm/drm_gem_framebuffer_helper.h>
16 #include <drm/drm_managed.h>
17 #include <drm/drm_modes.h>
18 #include <drm/drm_probe_helper.h>
19 #include <drm/drm_rect.h>
20 #include <linux/bitrev.h>
21 #include <linux/delay.h>
22 #include <linux/gpio/consumer.h>
23 #include <linux/kthread.h>
24 #include <linux/module.h>
25 #include <linux/mutex.h>
26 #include <linux/pwm.h>
27 #include <linux/spi/spi.h>
28
29 #define SHARP_MODE_PERIOD 8
30 #define SHARP_ADDR_PERIOD 8
31 #define SHARP_DUMMY_PERIOD 8
32
33 #define SHARP_MEMORY_DISPLAY_MAINTAIN_MODE 0
34 #define SHARP_MEMORY_DISPLAY_UPDATE_MODE 1
35 #define SHARP_MEMORY_DISPLAY_CLEAR_MODE 4
36
37 enum sharp_memory_model {
38 LS010B7DH04,
39 LS011B7DH03,
40 LS012B7DD01,
41 LS013B7DH03,
42 LS013B7DH05,
43 LS018B7DH02,
44 LS027B7DH01,
45 LS027B7DH01A,
46 LS032B7DD02,
47 LS044Q7DH01,
48 };
49
50 enum sharp_memory_vcom_mode {
51 SHARP_MEMORY_SOFTWARE_VCOM,
52 SHARP_MEMORY_EXTERNAL_VCOM,
53 SHARP_MEMORY_PWM_VCOM
54 };
55
56 struct sharp_memory_device {
57 struct drm_device drm;
58 struct spi_device *spi;
59
60 const struct drm_display_mode *mode;
61
62 struct drm_crtc crtc;
63 struct drm_plane plane;
64 struct drm_encoder encoder;
65 struct drm_connector connector;
66
67 struct gpio_desc *enable_gpio;
68
69 struct task_struct *sw_vcom_signal;
70 struct pwm_device *pwm_vcom_signal;
71
72 enum sharp_memory_vcom_mode vcom_mode;
73 u8 vcom;
74
75 u32 pitch;
76 u32 tx_buffer_size;
77 u8 *tx_buffer;
78
79 /* When vcom_mode == "software" a kthread is used to periodically send a
80 * 'maintain display' message over spi. This mutex ensures tx_buffer access
81 * and spi bus usage is synchronized in this case.
82 */
83 struct mutex tx_mutex;
84 };
85
sharp_memory_spi_write(struct spi_device * spi,void * buf,size_t len)86 static inline int sharp_memory_spi_write(struct spi_device *spi, void *buf, size_t len)
87 {
88 /* Reverse the bit order */
89 for (u8 *b = buf; b < ((u8 *)buf) + len; ++b)
90 *b = bitrev8(*b);
91
92 return spi_write(spi, buf, len);
93 }
94
drm_to_sharp_memory_device(struct drm_device * drm)95 static inline struct sharp_memory_device *drm_to_sharp_memory_device(struct drm_device *drm)
96 {
97 return container_of(drm, struct sharp_memory_device, drm);
98 }
99
100 DEFINE_DRM_GEM_DMA_FOPS(sharp_memory_fops);
101
102 static const struct drm_driver sharp_memory_drm_driver = {
103 .driver_features = DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC,
104 .fops = &sharp_memory_fops,
105 DRM_GEM_DMA_DRIVER_OPS_VMAP,
106 DRM_FBDEV_DMA_DRIVER_OPS,
107 .name = "sharp_memory_display",
108 .desc = "Sharp Display Memory LCD",
109 .major = 1,
110 .minor = 0,
111 };
112
sharp_memory_set_tx_buffer_mode(u8 * buffer,u8 mode,u8 vcom)113 static inline void sharp_memory_set_tx_buffer_mode(u8 *buffer, u8 mode, u8 vcom)
114 {
115 *buffer = mode | (vcom << 1);
116 }
117
sharp_memory_set_tx_buffer_addresses(u8 * buffer,struct drm_rect clip,u32 pitch)118 static inline void sharp_memory_set_tx_buffer_addresses(u8 *buffer,
119 struct drm_rect clip,
120 u32 pitch)
121 {
122 for (u32 line = 0; line < clip.y2; ++line)
123 buffer[line * pitch] = line + 1;
124 }
125
sharp_memory_set_tx_buffer_data(u8 * buffer,struct drm_framebuffer * fb,const struct iosys_map * vmap,struct drm_rect clip,u32 pitch,struct drm_format_conv_state * fmtcnv_state)126 static void sharp_memory_set_tx_buffer_data(u8 *buffer,
127 struct drm_framebuffer *fb,
128 const struct iosys_map *vmap,
129 struct drm_rect clip,
130 u32 pitch,
131 struct drm_format_conv_state *fmtcnv_state)
132 {
133 int ret;
134 struct iosys_map dst;
135
136 ret = drm_gem_fb_begin_cpu_access(fb, DMA_FROM_DEVICE);
137 if (ret)
138 return;
139
140 iosys_map_set_vaddr(&dst, buffer);
141
142 drm_fb_xrgb8888_to_mono(&dst, &pitch, vmap, fb, &clip, fmtcnv_state);
143
144 drm_gem_fb_end_cpu_access(fb, DMA_FROM_DEVICE);
145 }
146
sharp_memory_update_display(struct sharp_memory_device * smd,struct drm_framebuffer * fb,const struct iosys_map * vmap,struct drm_rect clip,struct drm_format_conv_state * fmtcnv_state)147 static int sharp_memory_update_display(struct sharp_memory_device *smd,
148 struct drm_framebuffer *fb,
149 const struct iosys_map *vmap,
150 struct drm_rect clip,
151 struct drm_format_conv_state *fmtcnv_state)
152 {
153 int ret;
154 u32 pitch = smd->pitch;
155 u8 vcom = smd->vcom;
156 u8 *tx_buffer = smd->tx_buffer;
157 u32 tx_buffer_size = smd->tx_buffer_size;
158
159 mutex_lock(&smd->tx_mutex);
160
161 /* Populate the transmit buffer with frame data */
162 sharp_memory_set_tx_buffer_mode(&tx_buffer[0],
163 SHARP_MEMORY_DISPLAY_UPDATE_MODE, vcom);
164 sharp_memory_set_tx_buffer_addresses(&tx_buffer[1], clip, pitch);
165 sharp_memory_set_tx_buffer_data(&tx_buffer[2], fb, vmap, clip, pitch, fmtcnv_state);
166
167 ret = sharp_memory_spi_write(smd->spi, tx_buffer, tx_buffer_size);
168
169 mutex_unlock(&smd->tx_mutex);
170
171 return ret;
172 }
173
sharp_memory_maintain_display(struct sharp_memory_device * smd)174 static int sharp_memory_maintain_display(struct sharp_memory_device *smd)
175 {
176 int ret;
177 u8 vcom = smd->vcom;
178 u8 *tx_buffer = smd->tx_buffer;
179
180 mutex_lock(&smd->tx_mutex);
181
182 sharp_memory_set_tx_buffer_mode(&tx_buffer[0], SHARP_MEMORY_DISPLAY_MAINTAIN_MODE, vcom);
183 tx_buffer[1] = 0; /* Write dummy data */
184 ret = sharp_memory_spi_write(smd->spi, tx_buffer, 2);
185
186 mutex_unlock(&smd->tx_mutex);
187
188 return ret;
189 }
190
sharp_memory_clear_display(struct sharp_memory_device * smd)191 static int sharp_memory_clear_display(struct sharp_memory_device *smd)
192 {
193 int ret;
194 u8 vcom = smd->vcom;
195 u8 *tx_buffer = smd->tx_buffer;
196
197 mutex_lock(&smd->tx_mutex);
198
199 sharp_memory_set_tx_buffer_mode(&tx_buffer[0], SHARP_MEMORY_DISPLAY_CLEAR_MODE, vcom);
200 tx_buffer[1] = 0; /* write dummy data */
201 ret = sharp_memory_spi_write(smd->spi, tx_buffer, 2);
202
203 mutex_unlock(&smd->tx_mutex);
204
205 return ret;
206 }
207
sharp_memory_fb_dirty(struct drm_framebuffer * fb,const struct iosys_map * vmap,struct drm_rect * rect,struct drm_format_conv_state * fmtconv_state)208 static void sharp_memory_fb_dirty(struct drm_framebuffer *fb, const struct iosys_map *vmap,
209 struct drm_rect *rect,
210 struct drm_format_conv_state *fmtconv_state)
211 {
212 struct drm_rect clip;
213 struct sharp_memory_device *smd = drm_to_sharp_memory_device(fb->dev);
214
215 /* Always update a full line regardless of what is dirty */
216 clip.x1 = 0;
217 clip.x2 = fb->width;
218 clip.y1 = rect->y1;
219 clip.y2 = rect->y2;
220
221 sharp_memory_update_display(smd, fb, vmap, clip, fmtconv_state);
222 }
223
sharp_memory_plane_atomic_check(struct drm_plane * plane,struct drm_atomic_commit * state)224 static int sharp_memory_plane_atomic_check(struct drm_plane *plane,
225 struct drm_atomic_commit *state)
226 {
227 struct drm_plane_state *plane_state = drm_atomic_get_new_plane_state(state, plane);
228 struct sharp_memory_device *smd;
229 struct drm_crtc_state *crtc_state;
230
231 smd = container_of(plane, struct sharp_memory_device, plane);
232 crtc_state = drm_atomic_get_new_crtc_state(state, &smd->crtc);
233
234 return drm_atomic_helper_check_plane_state(plane_state, crtc_state,
235 DRM_PLANE_NO_SCALING,
236 DRM_PLANE_NO_SCALING,
237 false, false);
238 }
239
sharp_memory_plane_atomic_update(struct drm_plane * plane,struct drm_atomic_commit * state)240 static void sharp_memory_plane_atomic_update(struct drm_plane *plane,
241 struct drm_atomic_commit *state)
242 {
243 struct drm_plane_state *old_state = drm_atomic_get_old_plane_state(state, plane);
244 struct drm_plane_state *plane_state = plane->state;
245 struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(plane_state);
246 struct sharp_memory_device *smd;
247 struct drm_rect rect;
248
249 smd = container_of(plane, struct sharp_memory_device, plane);
250 if (!smd->crtc.state->active)
251 return;
252
253 if (drm_atomic_helper_damage_merged(old_state, plane_state, &rect))
254 sharp_memory_fb_dirty(plane_state->fb, shadow_plane_state->data,
255 &rect, &shadow_plane_state->fmtcnv_state);
256 }
257
258 static const struct drm_plane_helper_funcs sharp_memory_plane_helper_funcs = {
259 .prepare_fb = drm_gem_plane_helper_prepare_fb,
260 .atomic_check = sharp_memory_plane_atomic_check,
261 .atomic_update = sharp_memory_plane_atomic_update,
262 DRM_GEM_SHADOW_PLANE_HELPER_FUNCS,
263 };
264
sharp_memory_format_mod_supported(struct drm_plane * plane,u32 format,u64 modifier)265 static bool sharp_memory_format_mod_supported(struct drm_plane *plane,
266 u32 format,
267 u64 modifier)
268 {
269 return modifier == DRM_FORMAT_MOD_LINEAR;
270 }
271
272 static const struct drm_plane_funcs sharp_memory_plane_funcs = {
273 .update_plane = drm_atomic_helper_update_plane,
274 .disable_plane = drm_atomic_helper_disable_plane,
275 .destroy = drm_plane_cleanup,
276 DRM_GEM_SHADOW_PLANE_FUNCS,
277 .format_mod_supported = sharp_memory_format_mod_supported,
278 };
279
sharp_memory_crtc_mode_valid(struct drm_crtc * crtc,const struct drm_display_mode * mode)280 static enum drm_mode_status sharp_memory_crtc_mode_valid(struct drm_crtc *crtc,
281 const struct drm_display_mode *mode)
282 {
283 struct sharp_memory_device *smd = drm_to_sharp_memory_device(crtc->dev);
284
285 return drm_crtc_helper_mode_valid_fixed(crtc, mode, smd->mode);
286 }
287
sharp_memory_crtc_check(struct drm_crtc * crtc,struct drm_atomic_commit * state)288 static int sharp_memory_crtc_check(struct drm_crtc *crtc,
289 struct drm_atomic_commit *state)
290 {
291 struct drm_crtc_state *crtc_state = drm_atomic_get_new_crtc_state(state, crtc);
292 int ret;
293
294 if (!crtc_state->enable)
295 goto out;
296
297 ret = drm_atomic_helper_check_crtc_primary_plane(crtc_state);
298 if (ret)
299 return ret;
300
301 out:
302 return drm_atomic_add_affected_planes(state, crtc);
303 }
304
sharp_memory_sw_vcom_signal_thread(void * data)305 static int sharp_memory_sw_vcom_signal_thread(void *data)
306 {
307 struct sharp_memory_device *smd = data;
308
309 while (!kthread_should_stop()) {
310 smd->vcom ^= 1; /* Toggle vcom */
311 sharp_memory_maintain_display(smd);
312 msleep(1000);
313 }
314
315 return 0;
316 }
317
sharp_memory_crtc_enable(struct drm_crtc * crtc,struct drm_atomic_commit * state)318 static void sharp_memory_crtc_enable(struct drm_crtc *crtc,
319 struct drm_atomic_commit *state)
320 {
321 struct sharp_memory_device *smd = drm_to_sharp_memory_device(crtc->dev);
322
323 sharp_memory_clear_display(smd);
324
325 if (smd->enable_gpio)
326 gpiod_set_value(smd->enable_gpio, 1);
327 }
328
sharp_memory_crtc_disable(struct drm_crtc * crtc,struct drm_atomic_commit * state)329 static void sharp_memory_crtc_disable(struct drm_crtc *crtc,
330 struct drm_atomic_commit *state)
331 {
332 struct sharp_memory_device *smd = drm_to_sharp_memory_device(crtc->dev);
333
334 sharp_memory_clear_display(smd);
335
336 if (smd->enable_gpio)
337 gpiod_set_value(smd->enable_gpio, 0);
338 }
339
340 static const struct drm_crtc_helper_funcs sharp_memory_crtc_helper_funcs = {
341 .mode_valid = sharp_memory_crtc_mode_valid,
342 .atomic_check = sharp_memory_crtc_check,
343 .atomic_enable = sharp_memory_crtc_enable,
344 .atomic_disable = sharp_memory_crtc_disable,
345 };
346
347 static const struct drm_crtc_funcs sharp_memory_crtc_funcs = {
348 .reset = drm_atomic_helper_crtc_reset,
349 .destroy = drm_crtc_cleanup,
350 .set_config = drm_atomic_helper_set_config,
351 .page_flip = drm_atomic_helper_page_flip,
352 .atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
353 .atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
354 };
355
356 static const struct drm_encoder_funcs sharp_memory_encoder_funcs = {
357 .destroy = drm_encoder_cleanup,
358 };
359
sharp_memory_connector_get_modes(struct drm_connector * connector)360 static int sharp_memory_connector_get_modes(struct drm_connector *connector)
361 {
362 struct sharp_memory_device *smd = drm_to_sharp_memory_device(connector->dev);
363
364 return drm_connector_helper_get_modes_fixed(connector, smd->mode);
365 }
366
367 static const struct drm_connector_helper_funcs sharp_memory_connector_hfuncs = {
368 .get_modes = sharp_memory_connector_get_modes,
369 };
370
371 static const struct drm_connector_funcs sharp_memory_connector_funcs = {
372 .reset = drm_atomic_helper_connector_reset,
373 .fill_modes = drm_helper_probe_single_connector_modes,
374 .destroy = drm_connector_cleanup,
375 .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
376 .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
377
378 };
379
380 static const struct drm_mode_config_funcs sharp_memory_mode_config_funcs = {
381 .fb_create = drm_gem_fb_create_with_dirty,
382 .atomic_check = drm_atomic_helper_check,
383 .atomic_commit = drm_atomic_helper_commit,
384 };
385
386 static const struct drm_display_mode sharp_memory_ls010b7dh04_mode = {
387 DRM_SIMPLE_MODE(128, 128, 18, 18),
388 };
389
390 static const struct drm_display_mode sharp_memory_ls011b7dh03_mode = {
391 DRM_SIMPLE_MODE(160, 68, 25, 10),
392 };
393
394 static const struct drm_display_mode sharp_memory_ls012b7dd01_mode = {
395 DRM_SIMPLE_MODE(184, 38, 29, 6),
396 };
397
398 static const struct drm_display_mode sharp_memory_ls013b7dh03_mode = {
399 DRM_SIMPLE_MODE(128, 128, 23, 23),
400 };
401
402 static const struct drm_display_mode sharp_memory_ls013b7dh05_mode = {
403 DRM_SIMPLE_MODE(144, 168, 20, 24),
404 };
405
406 static const struct drm_display_mode sharp_memory_ls018b7dh02_mode = {
407 DRM_SIMPLE_MODE(230, 303, 27, 36),
408 };
409
410 static const struct drm_display_mode sharp_memory_ls027b7dh01_mode = {
411 DRM_SIMPLE_MODE(400, 240, 58, 35),
412 };
413
414 static const struct drm_display_mode sharp_memory_ls032b7dd02_mode = {
415 DRM_SIMPLE_MODE(336, 536, 42, 68),
416 };
417
418 static const struct drm_display_mode sharp_memory_ls044q7dh01_mode = {
419 DRM_SIMPLE_MODE(320, 240, 89, 67),
420 };
421
422 static const struct spi_device_id sharp_memory_ids[] = {
423 {"ls010b7dh04", (kernel_ulong_t)&sharp_memory_ls010b7dh04_mode},
424 {"ls011b7dh03", (kernel_ulong_t)&sharp_memory_ls011b7dh03_mode},
425 {"ls012b7dd01", (kernel_ulong_t)&sharp_memory_ls012b7dd01_mode},
426 {"ls013b7dh03", (kernel_ulong_t)&sharp_memory_ls013b7dh03_mode},
427 {"ls013b7dh05", (kernel_ulong_t)&sharp_memory_ls013b7dh05_mode},
428 {"ls018b7dh02", (kernel_ulong_t)&sharp_memory_ls018b7dh02_mode},
429 {"ls027b7dh01", (kernel_ulong_t)&sharp_memory_ls027b7dh01_mode},
430 {"ls027b7dh01a", (kernel_ulong_t)&sharp_memory_ls027b7dh01_mode},
431 {"ls032b7dd02", (kernel_ulong_t)&sharp_memory_ls032b7dd02_mode},
432 {"ls044q7dh01", (kernel_ulong_t)&sharp_memory_ls044q7dh01_mode},
433 {},
434 };
435 MODULE_DEVICE_TABLE(spi, sharp_memory_ids);
436
437 static const struct of_device_id sharp_memory_of_match[] = {
438 {.compatible = "sharp,ls010b7dh04", &sharp_memory_ls010b7dh04_mode},
439 {.compatible = "sharp,ls011b7dh03", &sharp_memory_ls011b7dh03_mode},
440 {.compatible = "sharp,ls012b7dd01", &sharp_memory_ls012b7dd01_mode},
441 {.compatible = "sharp,ls013b7dh03", &sharp_memory_ls013b7dh03_mode},
442 {.compatible = "sharp,ls013b7dh05", &sharp_memory_ls013b7dh05_mode},
443 {.compatible = "sharp,ls018b7dh02", &sharp_memory_ls018b7dh02_mode},
444 {.compatible = "sharp,ls027b7dh01", &sharp_memory_ls027b7dh01_mode},
445 {.compatible = "sharp,ls027b7dh01a", &sharp_memory_ls027b7dh01_mode},
446 {.compatible = "sharp,ls032b7dd02", &sharp_memory_ls032b7dd02_mode},
447 {.compatible = "sharp,ls044q7dh01", &sharp_memory_ls044q7dh01_mode},
448 {},
449 };
450 MODULE_DEVICE_TABLE(of, sharp_memory_of_match);
451
452 static const u32 sharp_memory_formats[] = {
453 DRM_FORMAT_XRGB8888,
454 };
455
sharp_memory_pipe_init(struct drm_device * dev,struct sharp_memory_device * smd,const u32 * formats,unsigned int format_count,const u64 * format_modifiers)456 static int sharp_memory_pipe_init(struct drm_device *dev,
457 struct sharp_memory_device *smd,
458 const u32 *formats, unsigned int format_count,
459 const u64 *format_modifiers)
460 {
461 int ret;
462 struct drm_encoder *encoder = &smd->encoder;
463 struct drm_plane *plane = &smd->plane;
464 struct drm_crtc *crtc = &smd->crtc;
465 struct drm_connector *connector = &smd->connector;
466
467 drm_plane_helper_add(plane, &sharp_memory_plane_helper_funcs);
468 ret = drm_universal_plane_init(dev, plane, 0,
469 &sharp_memory_plane_funcs,
470 formats, format_count,
471 format_modifiers,
472 DRM_PLANE_TYPE_PRIMARY, NULL);
473 if (ret)
474 return ret;
475
476 drm_crtc_helper_add(crtc, &sharp_memory_crtc_helper_funcs);
477 ret = drm_crtc_init_with_planes(dev, crtc, plane, NULL,
478 &sharp_memory_crtc_funcs, NULL);
479 if (ret)
480 return ret;
481
482 encoder->possible_crtcs = drm_crtc_mask(crtc);
483 ret = drm_encoder_init(dev, encoder, &sharp_memory_encoder_funcs,
484 DRM_MODE_ENCODER_NONE, NULL);
485 if (ret)
486 return ret;
487
488 ret = drm_connector_init(&smd->drm, &smd->connector,
489 &sharp_memory_connector_funcs,
490 DRM_MODE_CONNECTOR_SPI);
491 if (ret)
492 return ret;
493
494 drm_connector_helper_add(&smd->connector,
495 &sharp_memory_connector_hfuncs);
496
497 return drm_connector_attach_encoder(connector, encoder);
498 }
499
sharp_memory_init_pwm_vcom_signal(struct sharp_memory_device * smd)500 static int sharp_memory_init_pwm_vcom_signal(struct sharp_memory_device *smd)
501 {
502 int ret;
503 struct device *dev = &smd->spi->dev;
504 struct pwm_state pwm_state;
505
506 smd->pwm_vcom_signal = devm_pwm_get(dev, NULL);
507 if (IS_ERR(smd->pwm_vcom_signal))
508 return dev_err_probe(dev, PTR_ERR(smd->pwm_vcom_signal),
509 "Could not get pwm device\n");
510
511 pwm_init_state(smd->pwm_vcom_signal, &pwm_state);
512 pwm_set_relative_duty_cycle(&pwm_state, 1, 10);
513 pwm_state.enabled = true;
514 ret = pwm_apply_might_sleep(smd->pwm_vcom_signal, &pwm_state);
515 if (ret)
516 return dev_err_probe(dev, -EINVAL, "Could not apply pwm state\n");
517
518 return 0;
519 }
520
sharp_memory_probe(struct spi_device * spi)521 static int sharp_memory_probe(struct spi_device *spi)
522 {
523 int ret;
524 struct device *dev;
525 struct sharp_memory_device *smd;
526 struct drm_device *drm;
527 const char *vcom_mode_str;
528
529 dev = &spi->dev;
530
531 ret = spi_setup(spi);
532 if (ret < 0)
533 return dev_err_probe(dev, ret, "Failed to setup spi device\n");
534
535 if (!dev->coherent_dma_mask) {
536 ret = dma_coerce_mask_and_coherent(dev, DMA_BIT_MASK(32));
537 if (ret)
538 return dev_err_probe(dev, ret, "Failed to set dma mask\n");
539 }
540
541 smd = devm_drm_dev_alloc(dev, &sharp_memory_drm_driver,
542 struct sharp_memory_device, drm);
543 if (IS_ERR(smd))
544 return PTR_ERR(smd);
545
546 spi_set_drvdata(spi, smd);
547
548 smd->spi = spi;
549 drm = &smd->drm;
550 ret = drmm_mode_config_init(drm);
551 if (ret)
552 return dev_err_probe(dev, ret, "Failed to initialize drm config\n");
553
554 smd->enable_gpio = devm_gpiod_get_optional(dev, "enable", GPIOD_OUT_HIGH);
555 if (!smd->enable_gpio)
556 dev_warn(dev, "Enable gpio not defined\n");
557
558 drm->mode_config.funcs = &sharp_memory_mode_config_funcs;
559 smd->mode = spi_get_device_match_data(spi);
560
561 smd->pitch = (SHARP_ADDR_PERIOD + smd->mode->hdisplay + SHARP_DUMMY_PERIOD) / 8;
562 smd->tx_buffer_size = (SHARP_MODE_PERIOD +
563 (SHARP_ADDR_PERIOD + (smd->mode->hdisplay) + SHARP_DUMMY_PERIOD) *
564 smd->mode->vdisplay) / 8;
565
566 smd->tx_buffer = devm_kzalloc(dev, smd->tx_buffer_size, GFP_KERNEL);
567 if (!smd->tx_buffer)
568 return -ENOMEM;
569
570 mutex_init(&smd->tx_mutex);
571
572 /*
573 * VCOM is a signal that prevents DC bias from being built up in
574 * the panel resulting in pixels being forever stuck in one state.
575 *
576 * This driver supports three different methods to generate this
577 * signal depending on EXTMODE pin:
578 *
579 * software (EXTMODE = L) - This mode uses a kthread to
580 * periodically send a "maintain display" message to the display,
581 * toggling the vcom bit on and off with each message
582 *
583 * external (EXTMODE = H) - This mode relies on an external
584 * clock to generate the signal on the EXTCOMM pin
585 *
586 * pwm (EXTMODE = H) - This mode uses a pwm device to generate
587 * the signal on the EXTCOMM pin
588 *
589 */
590 if (device_property_read_string(dev, "sharp,vcom-mode", &vcom_mode_str))
591 return dev_err_probe(dev, -EINVAL,
592 "Unable to find sharp,vcom-mode node in device tree\n");
593
594 if (!strcmp("software", vcom_mode_str)) {
595 smd->vcom_mode = SHARP_MEMORY_SOFTWARE_VCOM;
596 smd->sw_vcom_signal = kthread_run(sharp_memory_sw_vcom_signal_thread,
597 smd, "sw_vcom_signal");
598
599 } else if (!strcmp("external", vcom_mode_str)) {
600 smd->vcom_mode = SHARP_MEMORY_EXTERNAL_VCOM;
601
602 } else if (!strcmp("pwm", vcom_mode_str)) {
603 smd->vcom_mode = SHARP_MEMORY_PWM_VCOM;
604 ret = sharp_memory_init_pwm_vcom_signal(smd);
605 if (ret)
606 return ret;
607 } else {
608 return dev_err_probe(dev, -EINVAL, "Invalid value set for vcom-mode\n");
609 }
610
611 drm->mode_config.min_width = smd->mode->hdisplay;
612 drm->mode_config.max_width = smd->mode->hdisplay;
613 drm->mode_config.min_height = smd->mode->vdisplay;
614 drm->mode_config.max_height = smd->mode->vdisplay;
615
616 ret = sharp_memory_pipe_init(drm, smd, sharp_memory_formats,
617 ARRAY_SIZE(sharp_memory_formats),
618 NULL);
619 if (ret)
620 return dev_err_probe(dev, ret, "Failed to initialize display pipeline.\n");
621
622 drm_plane_enable_fb_damage_clips(&smd->plane);
623 drm_mode_config_reset(drm);
624
625 ret = drm_dev_register(drm, 0);
626 if (ret)
627 return dev_err_probe(dev, ret, "Failed to register drm device.\n");
628
629 drm_client_setup(drm, NULL);
630
631 return 0;
632 }
633
sharp_memory_remove(struct spi_device * spi)634 static void sharp_memory_remove(struct spi_device *spi)
635 {
636 struct sharp_memory_device *smd = spi_get_drvdata(spi);
637
638 drm_dev_unplug(&smd->drm);
639 drm_atomic_helper_shutdown(&smd->drm);
640
641 switch (smd->vcom_mode) {
642 case SHARP_MEMORY_SOFTWARE_VCOM:
643 kthread_stop(smd->sw_vcom_signal);
644 break;
645
646 case SHARP_MEMORY_EXTERNAL_VCOM:
647 break;
648
649 case SHARP_MEMORY_PWM_VCOM:
650 pwm_disable(smd->pwm_vcom_signal);
651 break;
652 }
653 }
654
655 static struct spi_driver sharp_memory_spi_driver = {
656 .driver = {
657 .name = "sharp_memory",
658 .of_match_table = sharp_memory_of_match,
659 },
660 .probe = sharp_memory_probe,
661 .remove = sharp_memory_remove,
662 .id_table = sharp_memory_ids,
663 };
664 module_spi_driver(sharp_memory_spi_driver);
665
666 MODULE_AUTHOR("Alex Lanzano <lanzano.alex@gmail.com>");
667 MODULE_DESCRIPTION("SPI Protocol driver for the sharp_memory display");
668 MODULE_LICENSE("GPL");
669