1
2
3
4
5
6
7
8#include <linux/delay.h>
9#include <linux/gpio/consumer.h>
10#include <linux/module.h>
11#include <linux/property.h>
12#include <linux/spi/spi.h>
13#include <video/mipi_display.h>
14
15#include <drm/drm_atomic_helper.h>
16#include <drm/drm_damage_helper.h>
17#include <drm/drm_drv.h>
18#include <drm/drm_fb_cma_helper.h>
19#include <drm/drm_fb_helper.h>
20#include <drm/drm_format_helper.h>
21#include <drm/drm_gem_atomic_helper.h>
22#include <drm/drm_gem_cma_helper.h>
23#include <drm/drm_gem_framebuffer_helper.h>
24#include <drm/drm_managed.h>
25#include <drm/drm_mipi_dbi.h>
26#include <drm/drm_rect.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
49
50
51
52
53
54
55
56
57
58
59
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, 0, 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 void *src = cma_obj->vaddr;
96 int ret = 0;
97
98 ret = drm_gem_fb_begin_cpu_access(fb, DMA_FROM_DEVICE);
99 if (ret)
100 return ret;
101
102 st7586_xrgb8888_to_gray332(dst, src, fb, clip);
103
104 drm_gem_fb_end_cpu_access(fb, DMA_FROM_DEVICE);
105
106 return 0;
107}
108
109static void st7586_fb_dirty(struct drm_framebuffer *fb, struct drm_rect *rect)
110{
111 struct mipi_dbi_dev *dbidev = drm_to_mipi_dbi_dev(fb->dev);
112 struct mipi_dbi *dbi = &dbidev->dbi;
113 int start, end, idx, ret = 0;
114
115 if (!drm_dev_enter(fb->dev, &idx))
116 return;
117
118
119 rect->x1 = rounddown(rect->x1, 3);
120 rect->x2 = roundup(rect->x2, 3);
121
122 DRM_DEBUG_KMS("Flushing [FB:%d] " DRM_RECT_FMT "\n", fb->base.id, DRM_RECT_ARG(rect));
123
124 ret = st7586_buf_copy(dbidev->tx_buf, fb, rect);
125 if (ret)
126 goto err_msg;
127
128
129 start = rect->x1 / 3;
130 end = rect->x2 / 3;
131
132 mipi_dbi_command(dbi, MIPI_DCS_SET_COLUMN_ADDRESS,
133 (start >> 8) & 0xFF, start & 0xFF,
134 (end >> 8) & 0xFF, (end - 1) & 0xFF);
135 mipi_dbi_command(dbi, MIPI_DCS_SET_PAGE_ADDRESS,
136 (rect->y1 >> 8) & 0xFF, rect->y1 & 0xFF,
137 (rect->y2 >> 8) & 0xFF, (rect->y2 - 1) & 0xFF);
138
139 ret = mipi_dbi_command_buf(dbi, MIPI_DCS_WRITE_MEMORY_START,
140 (u8 *)dbidev->tx_buf,
141 (end - start) * (rect->y2 - rect->y1));
142err_msg:
143 if (ret)
144 dev_err_once(fb->dev->dev, "Failed to update display %d\n", ret);
145
146 drm_dev_exit(idx);
147}
148
149static void st7586_pipe_update(struct drm_simple_display_pipe *pipe,
150 struct drm_plane_state *old_state)
151{
152 struct drm_plane_state *state = pipe->plane.state;
153 struct drm_rect rect;
154
155 if (!pipe->crtc.state->active)
156 return;
157
158 if (drm_atomic_helper_damage_merged(old_state, state, &rect))
159 st7586_fb_dirty(state->fb, &rect);
160}
161
162static void st7586_pipe_enable(struct drm_simple_display_pipe *pipe,
163 struct drm_crtc_state *crtc_state,
164 struct drm_plane_state *plane_state)
165{
166 struct mipi_dbi_dev *dbidev = drm_to_mipi_dbi_dev(pipe->crtc.dev);
167 struct drm_framebuffer *fb = plane_state->fb;
168 struct mipi_dbi *dbi = &dbidev->dbi;
169 struct drm_rect rect = {
170 .x1 = 0,
171 .x2 = fb->width,
172 .y1 = 0,
173 .y2 = fb->height,
174 };
175 int idx, ret;
176 u8 addr_mode;
177
178 if (!drm_dev_enter(pipe->crtc.dev, &idx))
179 return;
180
181 DRM_DEBUG_KMS("\n");
182
183 ret = mipi_dbi_poweron_reset(dbidev);
184 if (ret)
185 goto out_exit;
186
187 mipi_dbi_command(dbi, ST7586_AUTO_READ_CTRL, 0x9f);
188 mipi_dbi_command(dbi, ST7586_OTP_RW_CTRL, 0x00);
189
190 msleep(10);
191
192 mipi_dbi_command(dbi, ST7586_OTP_READ);
193
194 msleep(20);
195
196 mipi_dbi_command(dbi, ST7586_OTP_CTRL_OUT);
197 mipi_dbi_command(dbi, MIPI_DCS_EXIT_SLEEP_MODE);
198 mipi_dbi_command(dbi, MIPI_DCS_SET_DISPLAY_OFF);
199
200 msleep(50);
201
202 mipi_dbi_command(dbi, ST7586_SET_VOP_OFFSET, 0x00);
203 mipi_dbi_command(dbi, ST7586_SET_VOP, 0xe3, 0x00);
204 mipi_dbi_command(dbi, ST7586_SET_BIAS_SYSTEM, 0x02);
205 mipi_dbi_command(dbi, ST7586_SET_BOOST_LEVEL, 0x04);
206 mipi_dbi_command(dbi, ST7586_ENABLE_ANALOG, 0x1d);
207 mipi_dbi_command(dbi, ST7586_SET_NLINE_INV, 0x00);
208 mipi_dbi_command(dbi, ST7586_DISP_MODE_GRAY);
209 mipi_dbi_command(dbi, ST7586_ENABLE_DDRAM, 0x02);
210
211 switch (dbidev->rotation) {
212 default:
213 addr_mode = 0x00;
214 break;
215 case 90:
216 addr_mode = ST7586_DISP_CTRL_MY;
217 break;
218 case 180:
219 addr_mode = ST7586_DISP_CTRL_MX | ST7586_DISP_CTRL_MY;
220 break;
221 case 270:
222 addr_mode = ST7586_DISP_CTRL_MX;
223 break;
224 }
225 mipi_dbi_command(dbi, MIPI_DCS_SET_ADDRESS_MODE, addr_mode);
226
227 mipi_dbi_command(dbi, ST7586_SET_DISP_DUTY, 0x7f);
228 mipi_dbi_command(dbi, ST7586_SET_PART_DISP, 0xa0);
229 mipi_dbi_command(dbi, MIPI_DCS_SET_PARTIAL_ROWS, 0x00, 0x00, 0x00, 0x77);
230 mipi_dbi_command(dbi, MIPI_DCS_EXIT_INVERT_MODE);
231
232 msleep(100);
233
234 st7586_fb_dirty(fb, &rect);
235
236 mipi_dbi_command(dbi, MIPI_DCS_SET_DISPLAY_ON);
237out_exit:
238 drm_dev_exit(idx);
239}
240
241static void st7586_pipe_disable(struct drm_simple_display_pipe *pipe)
242{
243 struct mipi_dbi_dev *dbidev = drm_to_mipi_dbi_dev(pipe->crtc.dev);
244
245
246
247
248
249
250
251
252 DRM_DEBUG_KMS("\n");
253
254 mipi_dbi_command(&dbidev->dbi, MIPI_DCS_SET_DISPLAY_OFF);
255}
256
257static const u32 st7586_formats[] = {
258 DRM_FORMAT_XRGB8888,
259};
260
261static const struct drm_simple_display_pipe_funcs st7586_pipe_funcs = {
262 .enable = st7586_pipe_enable,
263 .disable = st7586_pipe_disable,
264 .update = st7586_pipe_update,
265};
266
267static const struct drm_display_mode st7586_mode = {
268 DRM_SIMPLE_MODE(178, 128, 37, 27),
269};
270
271DEFINE_DRM_GEM_CMA_FOPS(st7586_fops);
272
273static const struct drm_driver st7586_driver = {
274 .driver_features = DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC,
275 .fops = &st7586_fops,
276 DRM_GEM_CMA_DRIVER_OPS_VMAP,
277 .debugfs_init = mipi_dbi_debugfs_init,
278 .name = "st7586",
279 .desc = "Sitronix ST7586",
280 .date = "20170801",
281 .major = 1,
282 .minor = 0,
283};
284
285static const struct of_device_id st7586_of_match[] = {
286 { .compatible = "lego,ev3-lcd" },
287 {},
288};
289MODULE_DEVICE_TABLE(of, st7586_of_match);
290
291static const struct spi_device_id st7586_id[] = {
292 { "ev3-lcd", 0 },
293 { },
294};
295MODULE_DEVICE_TABLE(spi, st7586_id);
296
297static int st7586_probe(struct spi_device *spi)
298{
299 struct device *dev = &spi->dev;
300 struct mipi_dbi_dev *dbidev;
301 struct drm_device *drm;
302 struct mipi_dbi *dbi;
303 struct gpio_desc *a0;
304 u32 rotation = 0;
305 size_t bufsize;
306 int ret;
307
308 dbidev = devm_drm_dev_alloc(dev, &st7586_driver,
309 struct mipi_dbi_dev, drm);
310 if (IS_ERR(dbidev))
311 return PTR_ERR(dbidev);
312
313 dbi = &dbidev->dbi;
314 drm = &dbidev->drm;
315
316 bufsize = (st7586_mode.vdisplay + 2) / 3 * st7586_mode.hdisplay;
317
318 dbi->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
319 if (IS_ERR(dbi->reset))
320 return dev_err_probe(dev, PTR_ERR(dbi->reset), "Failed to get GPIO 'reset'\n");
321
322 a0 = devm_gpiod_get(dev, "a0", GPIOD_OUT_LOW);
323 if (IS_ERR(a0))
324 return dev_err_probe(dev, PTR_ERR(a0), "Failed to get GPIO 'a0'\n");
325
326 device_property_read_u32(dev, "rotation", &rotation);
327
328 ret = mipi_dbi_spi_init(spi, dbi, a0);
329 if (ret)
330 return ret;
331
332
333 dbi->read_commands = NULL;
334
335 ret = mipi_dbi_dev_init_with_formats(dbidev, &st7586_pipe_funcs,
336 st7586_formats, ARRAY_SIZE(st7586_formats),
337 &st7586_mode, rotation, bufsize);
338 if (ret)
339 return ret;
340
341
342
343
344
345
346
347
348 dbi->swap_bytes = true;
349
350 drm_mode_config_reset(drm);
351
352 ret = drm_dev_register(drm, 0);
353 if (ret)
354 return ret;
355
356 spi_set_drvdata(spi, drm);
357
358 drm_fbdev_generic_setup(drm, 0);
359
360 return 0;
361}
362
363static void st7586_remove(struct spi_device *spi)
364{
365 struct drm_device *drm = spi_get_drvdata(spi);
366
367 drm_dev_unplug(drm);
368 drm_atomic_helper_shutdown(drm);
369}
370
371static void st7586_shutdown(struct spi_device *spi)
372{
373 drm_atomic_helper_shutdown(spi_get_drvdata(spi));
374}
375
376static struct spi_driver st7586_spi_driver = {
377 .driver = {
378 .name = "st7586",
379 .owner = THIS_MODULE,
380 .of_match_table = st7586_of_match,
381 },
382 .id_table = st7586_id,
383 .probe = st7586_probe,
384 .remove = st7586_remove,
385 .shutdown = st7586_shutdown,
386};
387module_spi_driver(st7586_spi_driver);
388
389MODULE_DESCRIPTION("Sitronix ST7586 DRM driver");
390MODULE_AUTHOR("David Lechner <david@lechnology.com>");
391MODULE_LICENSE("GPL");
392
