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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_mipi_dbi.h>
25#include <drm/drm_rect.h>
26#include <drm/drm_vblank.h>
27
28
29#define ST7586_DISP_MODE_GRAY 0x38
30#define ST7586_DISP_MODE_MONO 0x39
31#define ST7586_ENABLE_DDRAM 0x3a
32#define ST7586_SET_DISP_DUTY 0xb0
33#define ST7586_SET_PART_DISP 0xb4
34#define ST7586_SET_NLINE_INV 0xb5
35#define ST7586_SET_VOP 0xc0
36#define ST7586_SET_BIAS_SYSTEM 0xc3
37#define ST7586_SET_BOOST_LEVEL 0xc4
38#define ST7586_SET_VOP_OFFSET 0xc7
39#define ST7586_ENABLE_ANALOG 0xd0
40#define ST7586_AUTO_READ_CTRL 0xd7
41#define ST7586_OTP_RW_CTRL 0xe0
42#define ST7586_OTP_CTRL_OUT 0xe1
43#define ST7586_OTP_READ 0xe3
44
45#define ST7586_DISP_CTRL_MX BIT(6)
46#define ST7586_DISP_CTRL_MY BIT(7)
47
48
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60
61
62static const u8 st7586_lookup[] = { 0x7, 0x4, 0x2, 0x0 };
63
64static void st7586_xrgb8888_to_gray332(u8 *dst, void *vaddr,
65 struct drm_framebuffer *fb,
66 struct drm_rect *clip)
67{
68 size_t len = (clip->x2 - clip->x1) * (clip->y2 - clip->y1);
69 unsigned int x, y;
70 u8 *src, *buf, val;
71
72 buf = kmalloc(len, GFP_KERNEL);
73 if (!buf)
74 return;
75
76 drm_fb_xrgb8888_to_gray8(buf, vaddr, fb, clip);
77 src = buf;
78
79 for (y = clip->y1; y < clip->y2; y++) {
80 for (x = clip->x1; x < clip->x2; x += 3) {
81 val = st7586_lookup[*src++ >> 6] << 5;
82 val |= st7586_lookup[*src++ >> 6] << 2;
83 val |= st7586_lookup[*src++ >> 6] >> 1;
84 *dst++ = val;
85 }
86 }
87
88 kfree(buf);
89}
90
91static int st7586_buf_copy(void *dst, struct drm_framebuffer *fb,
92 struct drm_rect *clip)
93{
94 struct drm_gem_cma_object *cma_obj = drm_fb_cma_get_gem_obj(fb, 0);
95 struct dma_buf_attachment *import_attach = cma_obj->base.import_attach;
96 void *src = cma_obj->vaddr;
97 int ret = 0;
98
99 if (import_attach) {
100 ret = dma_buf_begin_cpu_access(import_attach->dmabuf,
101 DMA_FROM_DEVICE);
102 if (ret)
103 return ret;
104 }
105
106 st7586_xrgb8888_to_gray332(dst, src, fb, clip);
107
108 if (import_attach)
109 ret = dma_buf_end_cpu_access(import_attach->dmabuf,
110 DMA_FROM_DEVICE);
111
112 return ret;
113}
114
115static void st7586_fb_dirty(struct drm_framebuffer *fb, struct drm_rect *rect)
116{
117 struct mipi_dbi_dev *dbidev = drm_to_mipi_dbi_dev(fb->dev);
118 struct mipi_dbi *dbi = &dbidev->dbi;
119 int start, end, idx, ret = 0;
120
121 if (!dbidev->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(dbidev->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(dbi, MIPI_DCS_SET_COLUMN_ADDRESS,
142 (start >> 8) & 0xFF, start & 0xFF,
143 (end >> 8) & 0xFF, (end - 1) & 0xFF);
144 mipi_dbi_command(dbi, 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(dbi, MIPI_DCS_WRITE_MEMORY_START,
149 (u8 *)dbidev->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_dev *dbidev = drm_to_mipi_dbi_dev(pipe->crtc.dev);
181 struct drm_framebuffer *fb = plane_state->fb;
182 struct mipi_dbi *dbi = &dbidev->dbi;
183 struct drm_rect rect = {
184 .x1 = 0,
185 .x2 = fb->width,
186 .y1 = 0,
187 .y2 = fb->height,
188 };
189 int idx, ret;
190 u8 addr_mode;
191
192 if (!drm_dev_enter(pipe->crtc.dev, &idx))
193 return;
194
195 DRM_DEBUG_KMS("\n");
196
197 ret = mipi_dbi_poweron_reset(dbidev);
198 if (ret)
199 goto out_exit;
200
201 mipi_dbi_command(dbi, ST7586_AUTO_READ_CTRL, 0x9f);
202 mipi_dbi_command(dbi, ST7586_OTP_RW_CTRL, 0x00);
203
204 msleep(10);
205
206 mipi_dbi_command(dbi, ST7586_OTP_READ);
207
208 msleep(20);
209
210 mipi_dbi_command(dbi, ST7586_OTP_CTRL_OUT);
211 mipi_dbi_command(dbi, MIPI_DCS_EXIT_SLEEP_MODE);
212 mipi_dbi_command(dbi, MIPI_DCS_SET_DISPLAY_OFF);
213
214 msleep(50);
215
216 mipi_dbi_command(dbi, ST7586_SET_VOP_OFFSET, 0x00);
217 mipi_dbi_command(dbi, ST7586_SET_VOP, 0xe3, 0x00);
218 mipi_dbi_command(dbi, ST7586_SET_BIAS_SYSTEM, 0x02);
219 mipi_dbi_command(dbi, ST7586_SET_BOOST_LEVEL, 0x04);
220 mipi_dbi_command(dbi, ST7586_ENABLE_ANALOG, 0x1d);
221 mipi_dbi_command(dbi, ST7586_SET_NLINE_INV, 0x00);
222 mipi_dbi_command(dbi, ST7586_DISP_MODE_GRAY);
223 mipi_dbi_command(dbi, ST7586_ENABLE_DDRAM, 0x02);
224
225 switch (dbidev->rotation) {
226 default:
227 addr_mode = 0x00;
228 break;
229 case 90:
230 addr_mode = ST7586_DISP_CTRL_MY;
231 break;
232 case 180:
233 addr_mode = ST7586_DISP_CTRL_MX | ST7586_DISP_CTRL_MY;
234 break;
235 case 270:
236 addr_mode = ST7586_DISP_CTRL_MX;
237 break;
238 }
239 mipi_dbi_command(dbi, MIPI_DCS_SET_ADDRESS_MODE, addr_mode);
240
241 mipi_dbi_command(dbi, ST7586_SET_DISP_DUTY, 0x7f);
242 mipi_dbi_command(dbi, ST7586_SET_PART_DISP, 0xa0);
243 mipi_dbi_command(dbi, MIPI_DCS_SET_PARTIAL_AREA, 0x00, 0x00, 0x00, 0x77);
244 mipi_dbi_command(dbi, MIPI_DCS_EXIT_INVERT_MODE);
245
246 msleep(100);
247
248 dbidev->enabled = true;
249 st7586_fb_dirty(fb, &rect);
250
251 mipi_dbi_command(dbi, MIPI_DCS_SET_DISPLAY_ON);
252out_exit:
253 drm_dev_exit(idx);
254}
255
256static void st7586_pipe_disable(struct drm_simple_display_pipe *pipe)
257{
258 struct mipi_dbi_dev *dbidev = drm_to_mipi_dbi_dev(pipe->crtc.dev);
259
260
261
262
263
264
265
266
267 DRM_DEBUG_KMS("\n");
268
269 if (!dbidev->enabled)
270 return;
271
272 mipi_dbi_command(&dbidev->dbi, MIPI_DCS_SET_DISPLAY_OFF);
273 dbidev->enabled = false;
274}
275
276static const u32 st7586_formats[] = {
277 DRM_FORMAT_XRGB8888,
278};
279
280static const struct drm_simple_display_pipe_funcs st7586_pipe_funcs = {
281 .enable = st7586_pipe_enable,
282 .disable = st7586_pipe_disable,
283 .update = st7586_pipe_update,
284 .prepare_fb = drm_gem_fb_simple_display_pipe_prepare_fb,
285};
286
287static const struct drm_display_mode st7586_mode = {
288 DRM_SIMPLE_MODE(178, 128, 37, 27),
289};
290
291DEFINE_DRM_GEM_CMA_FOPS(st7586_fops);
292
293static struct drm_driver st7586_driver = {
294 .driver_features = DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC,
295 .fops = &st7586_fops,
296 .release = mipi_dbi_release,
297 DRM_GEM_CMA_VMAP_DRIVER_OPS,
298 .debugfs_init = mipi_dbi_debugfs_init,
299 .name = "st7586",
300 .desc = "Sitronix ST7586",
301 .date = "20170801",
302 .major = 1,
303 .minor = 0,
304};
305
306static const struct of_device_id st7586_of_match[] = {
307 { .compatible = "lego,ev3-lcd" },
308 {},
309};
310MODULE_DEVICE_TABLE(of, st7586_of_match);
311
312static const struct spi_device_id st7586_id[] = {
313 { "ev3-lcd", 0 },
314 { },
315};
316MODULE_DEVICE_TABLE(spi, st7586_id);
317
318static int st7586_probe(struct spi_device *spi)
319{
320 struct device *dev = &spi->dev;
321 struct mipi_dbi_dev *dbidev;
322 struct drm_device *drm;
323 struct mipi_dbi *dbi;
324 struct gpio_desc *a0;
325 u32 rotation = 0;
326 size_t bufsize;
327 int ret;
328
329 dbidev = kzalloc(sizeof(*dbidev), GFP_KERNEL);
330 if (!dbidev)
331 return -ENOMEM;
332
333 dbi = &dbidev->dbi;
334 drm = &dbidev->drm;
335 ret = devm_drm_dev_init(dev, drm, &st7586_driver);
336 if (ret) {
337 kfree(dbidev);
338 return ret;
339 }
340
341 drm_mode_config_init(drm);
342
343 bufsize = (st7586_mode.vdisplay + 2) / 3 * st7586_mode.hdisplay;
344
345 dbi->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
346 if (IS_ERR(dbi->reset)) {
347 DRM_DEV_ERROR(dev, "Failed to get gpio 'reset'\n");
348 return PTR_ERR(dbi->reset);
349 }
350
351 a0 = devm_gpiod_get(dev, "a0", GPIOD_OUT_LOW);
352 if (IS_ERR(a0)) {
353 DRM_DEV_ERROR(dev, "Failed to get gpio 'a0'\n");
354 return PTR_ERR(a0);
355 }
356
357 device_property_read_u32(dev, "rotation", &rotation);
358
359 ret = mipi_dbi_spi_init(spi, dbi, a0);
360 if (ret)
361 return ret;
362
363
364 dbi->read_commands = NULL;
365
366 ret = mipi_dbi_dev_init_with_formats(dbidev, &st7586_pipe_funcs,
367 st7586_formats, ARRAY_SIZE(st7586_formats),
368 &st7586_mode, rotation, bufsize);
369 if (ret)
370 return ret;
371
372
373
374
375
376
377
378
379 dbi->swap_bytes = true;
380
381 drm_mode_config_reset(drm);
382
383 ret = drm_dev_register(drm, 0);
384 if (ret)
385 return ret;
386
387 spi_set_drvdata(spi, drm);
388
389 drm_fbdev_generic_setup(drm, 0);
390
391 return 0;
392}
393
394static int st7586_remove(struct spi_device *spi)
395{
396 struct drm_device *drm = spi_get_drvdata(spi);
397
398 drm_dev_unplug(drm);
399 drm_atomic_helper_shutdown(drm);
400
401 return 0;
402}
403
404static void st7586_shutdown(struct spi_device *spi)
405{
406 drm_atomic_helper_shutdown(spi_get_drvdata(spi));
407}
408
409static struct spi_driver st7586_spi_driver = {
410 .driver = {
411 .name = "st7586",
412 .owner = THIS_MODULE,
413 .of_match_table = st7586_of_match,
414 },
415 .id_table = st7586_id,
416 .probe = st7586_probe,
417 .remove = st7586_remove,
418 .shutdown = st7586_shutdown,
419};
420module_spi_driver(st7586_spi_driver);
421
422MODULE_DESCRIPTION("Sitronix ST7586 DRM driver");
423MODULE_AUTHOR("David Lechner <david@lechnology.com>");
424MODULE_LICENSE("GPL");
425
