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8#include <linux/delay.h>
9#include <linux/dma-buf.h>
10#include <linux/gpio/consumer.h>
11#include <linux/module.h>
12#include <linux/property.h>
13#include <linux/spi/spi.h>
14#include <video/mipi_display.h>
15
16#include <drm/drm_atomic_helper.h>
17#include <drm/drm_damage_helper.h>
18#include <drm/drm_drv.h>
19#include <drm/drm_fb_cma_helper.h>
20#include <drm/drm_fb_helper.h>
21#include <drm/drm_format_helper.h>
22#include <drm/drm_gem_cma_helper.h>
23#include <drm/drm_gem_framebuffer_helper.h>
24#include <drm/drm_rect.h>
25#include <drm/drm_vblank.h>
26#include <drm/tinydrm/mipi-dbi.h>
27#include <drm/tinydrm/tinydrm-helpers.h>
28
29
30#define ST7586_DISP_MODE_GRAY 0x38
31#define ST7586_DISP_MODE_MONO 0x39
32#define ST7586_ENABLE_DDRAM 0x3a
33#define ST7586_SET_DISP_DUTY 0xb0
34#define ST7586_SET_PART_DISP 0xb4
35#define ST7586_SET_NLINE_INV 0xb5
36#define ST7586_SET_VOP 0xc0
37#define ST7586_SET_BIAS_SYSTEM 0xc3
38#define ST7586_SET_BOOST_LEVEL 0xc4
39#define ST7586_SET_VOP_OFFSET 0xc7
40#define ST7586_ENABLE_ANALOG 0xd0
41#define ST7586_AUTO_READ_CTRL 0xd7
42#define ST7586_OTP_RW_CTRL 0xe0
43#define ST7586_OTP_CTRL_OUT 0xe1
44#define ST7586_OTP_READ 0xe3
45
46#define ST7586_DISP_CTRL_MX BIT(6)
47#define ST7586_DISP_CTRL_MY BIT(7)
48
49
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61
62
63static const u8 st7586_lookup[] = { 0x7, 0x4, 0x2, 0x0 };
64
65static void st7586_xrgb8888_to_gray332(u8 *dst, void *vaddr,
66 struct drm_framebuffer *fb,
67 struct drm_rect *clip)
68{
69 size_t len = (clip->x2 - clip->x1) * (clip->y2 - clip->y1);
70 unsigned int x, y;
71 u8 *src, *buf, val;
72
73 buf = kmalloc(len, GFP_KERNEL);
74 if (!buf)
75 return;
76
77 drm_fb_xrgb8888_to_gray8(buf, vaddr, fb, clip);
78 src = buf;
79
80 for (y = clip->y1; y < clip->y2; y++) {
81 for (x = clip->x1; x < clip->x2; x += 3) {
82 val = st7586_lookup[*src++ >> 6] << 5;
83 val |= st7586_lookup[*src++ >> 6] << 2;
84 val |= st7586_lookup[*src++ >> 6] >> 1;
85 *dst++ = val;
86 }
87 }
88
89 kfree(buf);
90}
91
92static int st7586_buf_copy(void *dst, struct drm_framebuffer *fb,
93 struct drm_rect *clip)
94{
95 struct drm_gem_cma_object *cma_obj = drm_fb_cma_get_gem_obj(fb, 0);
96 struct dma_buf_attachment *import_attach = cma_obj->base.import_attach;
97 void *src = cma_obj->vaddr;
98 int ret = 0;
99
100 if (import_attach) {
101 ret = dma_buf_begin_cpu_access(import_attach->dmabuf,
102 DMA_FROM_DEVICE);
103 if (ret)
104 return ret;
105 }
106
107 st7586_xrgb8888_to_gray332(dst, src, fb, clip);
108
109 if (import_attach)
110 ret = dma_buf_end_cpu_access(import_attach->dmabuf,
111 DMA_FROM_DEVICE);
112
113 return ret;
114}
115
116static void st7586_fb_dirty(struct drm_framebuffer *fb, struct drm_rect *rect)
117{
118 struct mipi_dbi *mipi = drm_to_mipi_dbi(fb->dev);
119 int start, end, idx, ret = 0;
120
121 if (!mipi->enabled)
122 return;
123
124 if (!drm_dev_enter(fb->dev, &idx))
125 return;
126
127
128 rect->x1 = rounddown(rect->x1, 3);
129 rect->x2 = roundup(rect->x2, 3);
130
131 DRM_DEBUG_KMS("Flushing [FB:%d] " DRM_RECT_FMT "\n", fb->base.id, DRM_RECT_ARG(rect));
132
133 ret = st7586_buf_copy(mipi->tx_buf, fb, rect);
134 if (ret)
135 goto err_msg;
136
137
138 start = rect->x1 / 3;
139 end = rect->x2 / 3;
140
141 mipi_dbi_command(mipi, MIPI_DCS_SET_COLUMN_ADDRESS,
142 (start >> 8) & 0xFF, start & 0xFF,
143 (end >> 8) & 0xFF, (end - 1) & 0xFF);
144 mipi_dbi_command(mipi, MIPI_DCS_SET_PAGE_ADDRESS,
145 (rect->y1 >> 8) & 0xFF, rect->y1 & 0xFF,
146 (rect->y2 >> 8) & 0xFF, (rect->y2 - 1) & 0xFF);
147
148 ret = mipi_dbi_command_buf(mipi, MIPI_DCS_WRITE_MEMORY_START,
149 (u8 *)mipi->tx_buf,
150 (end - start) * (rect->y2 - rect->y1));
151err_msg:
152 if (ret)
153 dev_err_once(fb->dev->dev, "Failed to update display %d\n", ret);
154
155 drm_dev_exit(idx);
156}
157
158static void st7586_pipe_update(struct drm_simple_display_pipe *pipe,
159 struct drm_plane_state *old_state)
160{
161 struct drm_plane_state *state = pipe->plane.state;
162 struct drm_crtc *crtc = &pipe->crtc;
163 struct drm_rect rect;
164
165 if (drm_atomic_helper_damage_merged(old_state, state, &rect))
166 st7586_fb_dirty(state->fb, &rect);
167
168 if (crtc->state->event) {
169 spin_lock_irq(&crtc->dev->event_lock);
170 drm_crtc_send_vblank_event(crtc, crtc->state->event);
171 spin_unlock_irq(&crtc->dev->event_lock);
172 crtc->state->event = NULL;
173 }
174}
175
176static void st7586_pipe_enable(struct drm_simple_display_pipe *pipe,
177 struct drm_crtc_state *crtc_state,
178 struct drm_plane_state *plane_state)
179{
180 struct mipi_dbi *mipi = drm_to_mipi_dbi(pipe->crtc.dev);
181 struct drm_framebuffer *fb = plane_state->fb;
182 struct drm_rect rect = {
183 .x1 = 0,
184 .x2 = fb->width,
185 .y1 = 0,
186 .y2 = fb->height,
187 };
188 int idx, ret;
189 u8 addr_mode;
190
191 if (!drm_dev_enter(pipe->crtc.dev, &idx))
192 return;
193
194 DRM_DEBUG_KMS("\n");
195
196 ret = mipi_dbi_poweron_reset(mipi);
197 if (ret)
198 goto out_exit;
199
200 mipi_dbi_command(mipi, ST7586_AUTO_READ_CTRL, 0x9f);
201 mipi_dbi_command(mipi, ST7586_OTP_RW_CTRL, 0x00);
202
203 msleep(10);
204
205 mipi_dbi_command(mipi, ST7586_OTP_READ);
206
207 msleep(20);
208
209 mipi_dbi_command(mipi, ST7586_OTP_CTRL_OUT);
210 mipi_dbi_command(mipi, MIPI_DCS_EXIT_SLEEP_MODE);
211 mipi_dbi_command(mipi, MIPI_DCS_SET_DISPLAY_OFF);
212
213 msleep(50);
214
215 mipi_dbi_command(mipi, ST7586_SET_VOP_OFFSET, 0x00);
216 mipi_dbi_command(mipi, ST7586_SET_VOP, 0xe3, 0x00);
217 mipi_dbi_command(mipi, ST7586_SET_BIAS_SYSTEM, 0x02);
218 mipi_dbi_command(mipi, ST7586_SET_BOOST_LEVEL, 0x04);
219 mipi_dbi_command(mipi, ST7586_ENABLE_ANALOG, 0x1d);
220 mipi_dbi_command(mipi, ST7586_SET_NLINE_INV, 0x00);
221 mipi_dbi_command(mipi, ST7586_DISP_MODE_GRAY);
222 mipi_dbi_command(mipi, ST7586_ENABLE_DDRAM, 0x02);
223
224 switch (mipi->rotation) {
225 default:
226 addr_mode = 0x00;
227 break;
228 case 90:
229 addr_mode = ST7586_DISP_CTRL_MY;
230 break;
231 case 180:
232 addr_mode = ST7586_DISP_CTRL_MX | ST7586_DISP_CTRL_MY;
233 break;
234 case 270:
235 addr_mode = ST7586_DISP_CTRL_MX;
236 break;
237 }
238 mipi_dbi_command(mipi, MIPI_DCS_SET_ADDRESS_MODE, addr_mode);
239
240 mipi_dbi_command(mipi, ST7586_SET_DISP_DUTY, 0x7f);
241 mipi_dbi_command(mipi, ST7586_SET_PART_DISP, 0xa0);
242 mipi_dbi_command(mipi, MIPI_DCS_SET_PARTIAL_AREA, 0x00, 0x00, 0x00, 0x77);
243 mipi_dbi_command(mipi, MIPI_DCS_EXIT_INVERT_MODE);
244
245 msleep(100);
246
247 mipi->enabled = true;
248 st7586_fb_dirty(fb, &rect);
249
250 mipi_dbi_command(mipi, MIPI_DCS_SET_DISPLAY_ON);
251out_exit:
252 drm_dev_exit(idx);
253}
254
255static void st7586_pipe_disable(struct drm_simple_display_pipe *pipe)
256{
257 struct mipi_dbi *mipi = drm_to_mipi_dbi(pipe->crtc.dev);
258
259
260
261
262
263
264
265
266 DRM_DEBUG_KMS("\n");
267
268 if (!mipi->enabled)
269 return;
270
271 mipi_dbi_command(mipi, MIPI_DCS_SET_DISPLAY_OFF);
272 mipi->enabled = false;
273}
274
275static const u32 st7586_formats[] = {
276 DRM_FORMAT_XRGB8888,
277};
278
279static const struct drm_simple_display_pipe_funcs st7586_pipe_funcs = {
280 .enable = st7586_pipe_enable,
281 .disable = st7586_pipe_disable,
282 .update = st7586_pipe_update,
283 .prepare_fb = drm_gem_fb_simple_display_pipe_prepare_fb,
284};
285
286static const struct drm_mode_config_funcs st7586_mode_config_funcs = {
287 .fb_create = drm_gem_fb_create_with_dirty,
288 .atomic_check = drm_atomic_helper_check,
289 .atomic_commit = drm_atomic_helper_commit,
290};
291
292static const struct drm_display_mode st7586_mode = {
293 DRM_SIMPLE_MODE(178, 128, 37, 27),
294};
295
296DEFINE_DRM_GEM_CMA_FOPS(st7586_fops);
297
298static struct drm_driver st7586_driver = {
299 .driver_features = DRIVER_GEM | DRIVER_MODESET | DRIVER_PRIME |
300 DRIVER_ATOMIC,
301 .fops = &st7586_fops,
302 .release = mipi_dbi_release,
303 DRM_GEM_CMA_VMAP_DRIVER_OPS,
304 .debugfs_init = mipi_dbi_debugfs_init,
305 .name = "st7586",
306 .desc = "Sitronix ST7586",
307 .date = "20170801",
308 .major = 1,
309 .minor = 0,
310};
311
312static const struct of_device_id st7586_of_match[] = {
313 { .compatible = "lego,ev3-lcd" },
314 {},
315};
316MODULE_DEVICE_TABLE(of, st7586_of_match);
317
318static const struct spi_device_id st7586_id[] = {
319 { "ev3-lcd", 0 },
320 { },
321};
322MODULE_DEVICE_TABLE(spi, st7586_id);
323
324static int st7586_probe(struct spi_device *spi)
325{
326 struct device *dev = &spi->dev;
327 struct drm_device *drm;
328 struct mipi_dbi *mipi;
329 struct gpio_desc *a0;
330 u32 rotation = 0;
331 size_t bufsize;
332 int ret;
333
334 mipi = kzalloc(sizeof(*mipi), GFP_KERNEL);
335 if (!mipi)
336 return -ENOMEM;
337
338 drm = &mipi->drm;
339 ret = devm_drm_dev_init(dev, drm, &st7586_driver);
340 if (ret) {
341 kfree(mipi);
342 return ret;
343 }
344
345 drm_mode_config_init(drm);
346 drm->mode_config.preferred_depth = 32;
347 drm->mode_config.funcs = &st7586_mode_config_funcs;
348
349 mutex_init(&mipi->cmdlock);
350
351 bufsize = (st7586_mode.vdisplay + 2) / 3 * st7586_mode.hdisplay;
352 mipi->tx_buf = devm_kmalloc(dev, bufsize, GFP_KERNEL);
353 if (!mipi->tx_buf)
354 return -ENOMEM;
355
356 mipi->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
357 if (IS_ERR(mipi->reset)) {
358 DRM_DEV_ERROR(dev, "Failed to get gpio 'reset'\n");
359 return PTR_ERR(mipi->reset);
360 }
361
362 a0 = devm_gpiod_get(dev, "a0", GPIOD_OUT_LOW);
363 if (IS_ERR(a0)) {
364 DRM_DEV_ERROR(dev, "Failed to get gpio 'a0'\n");
365 return PTR_ERR(a0);
366 }
367
368 device_property_read_u32(dev, "rotation", &rotation);
369 mipi->rotation = rotation;
370
371 ret = mipi_dbi_spi_init(spi, mipi, a0);
372 if (ret)
373 return ret;
374
375
376 mipi->read_commands = NULL;
377
378
379
380
381
382
383
384
385 mipi->swap_bytes = true;
386
387 ret = tinydrm_display_pipe_init(drm, &mipi->pipe, &st7586_pipe_funcs,
388 DRM_MODE_CONNECTOR_VIRTUAL,
389 st7586_formats, ARRAY_SIZE(st7586_formats),
390 &st7586_mode, rotation);
391 if (ret)
392 return ret;
393
394 drm_plane_enable_fb_damage_clips(&mipi->pipe.plane);
395
396 drm_mode_config_reset(drm);
397
398 ret = drm_dev_register(drm, 0);
399 if (ret)
400 return ret;
401
402 spi_set_drvdata(spi, drm);
403
404 DRM_DEBUG_KMS("preferred_depth=%u, rotation = %u\n",
405 drm->mode_config.preferred_depth, rotation);
406
407 drm_fbdev_generic_setup(drm, 0);
408
409 return 0;
410}
411
412static int st7586_remove(struct spi_device *spi)
413{
414 struct drm_device *drm = spi_get_drvdata(spi);
415
416 drm_dev_unplug(drm);
417 drm_atomic_helper_shutdown(drm);
418
419 return 0;
420}
421
422static void st7586_shutdown(struct spi_device *spi)
423{
424 drm_atomic_helper_shutdown(spi_get_drvdata(spi));
425}
426
427static struct spi_driver st7586_spi_driver = {
428 .driver = {
429 .name = "st7586",
430 .owner = THIS_MODULE,
431 .of_match_table = st7586_of_match,
432 },
433 .id_table = st7586_id,
434 .probe = st7586_probe,
435 .remove = st7586_remove,
436 .shutdown = st7586_shutdown,
437};
438module_spi_driver(st7586_spi_driver);
439
440MODULE_DESCRIPTION("Sitronix ST7586 DRM driver");
441MODULE_AUTHOR("David Lechner <david@lechnology.com>");
442MODULE_LICENSE("GPL");
443
