1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * DRM driver for display panels connected to a Sitronix ST7715R or ST7735R
4 * display controller in SPI mode.
5 *
6 * Copyright 2017 David Lechner <david@lechnology.com>
7 * Copyright (C) 2019 Glider bvba
8 */
9
10 #include <linux/backlight.h>
11 #include <linux/delay.h>
12 #include <linux/dma-buf.h>
13 #include <linux/gpio/consumer.h>
14 #include <linux/module.h>
15 #include <linux/property.h>
16 #include <linux/spi/spi.h>
17 #include <video/mipi_display.h>
18
19 #include <drm/clients/drm_client_setup.h>
20 #include <drm/drm_atomic_helper.h>
21 #include <drm/drm_drv.h>
22 #include <drm/drm_fbdev_dma.h>
23 #include <drm/drm_gem_atomic_helper.h>
24 #include <drm/drm_gem_dma_helper.h>
25 #include <drm/drm_managed.h>
26 #include <drm/drm_mipi_dbi.h>
27 #include <drm/drm_print.h>
28
29 #define ST7735R_FRMCTR1 0xb1
30 #define ST7735R_FRMCTR2 0xb2
31 #define ST7735R_FRMCTR3 0xb3
32 #define ST7735R_INVCTR 0xb4
33 #define ST7735R_PWCTR1 0xc0
34 #define ST7735R_PWCTR2 0xc1
35 #define ST7735R_PWCTR3 0xc2
36 #define ST7735R_PWCTR4 0xc3
37 #define ST7735R_PWCTR5 0xc4
38 #define ST7735R_VMCTR1 0xc5
39 #define ST7735R_GAMCTRP1 0xe0
40 #define ST7735R_GAMCTRN1 0xe1
41
42 #define ST7735R_MY BIT(7)
43 #define ST7735R_MX BIT(6)
44 #define ST7735R_MV BIT(5)
45 #define ST7735R_RGB BIT(3)
46
47 struct st7735r_cfg {
48 const struct drm_display_mode mode;
49 unsigned int left_offset;
50 unsigned int top_offset;
51 unsigned int write_only:1;
52 unsigned int rgb:1; /* RGB (vs. BGR) */
53 };
54
55 struct st7735r_device {
56 struct mipi_dbi_dev dbidev; /* Must be first for .release() */
57 const struct st7735r_cfg *cfg;
58
59 struct drm_plane plane;
60 struct drm_crtc crtc;
61 struct drm_encoder encoder;
62 struct drm_connector connector;
63 };
64
to_st7735r_device(struct drm_device * drm)65 static struct st7735r_device *to_st7735r_device(struct drm_device *drm)
66 {
67 return container_of(drm_to_mipi_dbi_dev(drm), struct st7735r_device, dbidev);
68 }
69
70 static const u32 st7735r_plane_formats[] = {
71 DRM_MIPI_DBI_PLANE_FORMATS,
72 };
73
74 static const u64 st7735r_plane_format_modifiers[] = {
75 DRM_MIPI_DBI_PLANE_FORMAT_MODIFIERS,
76 };
77
78 static const struct drm_plane_helper_funcs st7735r_plane_helper_funcs = {
79 DRM_MIPI_DBI_PLANE_HELPER_FUNCS,
80 };
81
82 static const struct drm_plane_funcs st7735r_plane_funcs = {
83 DRM_MIPI_DBI_PLANE_FUNCS,
84 .destroy = drm_plane_cleanup,
85 };
86
st7735r_crtc_helper_atomic_enable(struct drm_crtc * crtc,struct drm_atomic_state * state)87 static void st7735r_crtc_helper_atomic_enable(struct drm_crtc *crtc,
88 struct drm_atomic_state *state)
89 {
90 struct drm_device *drm = crtc->dev;
91 struct st7735r_device *st7735r = to_st7735r_device(drm);
92 struct mipi_dbi_dev *dbidev = &st7735r->dbidev;
93 struct mipi_dbi *dbi = &dbidev->dbi;
94 int ret, idx;
95 u8 addr_mode;
96
97 if (!drm_dev_enter(drm, &idx))
98 return;
99
100 DRM_DEBUG_KMS("\n");
101
102 ret = mipi_dbi_poweron_reset(dbidev);
103 if (ret)
104 goto out_exit;
105
106 msleep(150);
107
108 mipi_dbi_command(dbi, MIPI_DCS_EXIT_SLEEP_MODE);
109 msleep(500);
110
111 mipi_dbi_command(dbi, ST7735R_FRMCTR1, 0x01, 0x2c, 0x2d);
112 mipi_dbi_command(dbi, ST7735R_FRMCTR2, 0x01, 0x2c, 0x2d);
113 mipi_dbi_command(dbi, ST7735R_FRMCTR3, 0x01, 0x2c, 0x2d, 0x01, 0x2c,
114 0x2d);
115 mipi_dbi_command(dbi, ST7735R_INVCTR, 0x07);
116 mipi_dbi_command(dbi, ST7735R_PWCTR1, 0xa2, 0x02, 0x84);
117 mipi_dbi_command(dbi, ST7735R_PWCTR2, 0xc5);
118 mipi_dbi_command(dbi, ST7735R_PWCTR3, 0x0a, 0x00);
119 mipi_dbi_command(dbi, ST7735R_PWCTR4, 0x8a, 0x2a);
120 mipi_dbi_command(dbi, ST7735R_PWCTR5, 0x8a, 0xee);
121 mipi_dbi_command(dbi, ST7735R_VMCTR1, 0x0e);
122 mipi_dbi_command(dbi, MIPI_DCS_EXIT_INVERT_MODE);
123 switch (dbidev->rotation) {
124 default:
125 addr_mode = ST7735R_MX | ST7735R_MY;
126 break;
127 case 90:
128 addr_mode = ST7735R_MX | ST7735R_MV;
129 break;
130 case 180:
131 addr_mode = 0;
132 break;
133 case 270:
134 addr_mode = ST7735R_MY | ST7735R_MV;
135 break;
136 }
137
138 if (st7735r->cfg->rgb)
139 addr_mode |= ST7735R_RGB;
140
141 mipi_dbi_command(dbi, MIPI_DCS_SET_ADDRESS_MODE, addr_mode);
142 mipi_dbi_command(dbi, MIPI_DCS_SET_PIXEL_FORMAT,
143 MIPI_DCS_PIXEL_FMT_16BIT);
144 mipi_dbi_command(dbi, ST7735R_GAMCTRP1, 0x02, 0x1c, 0x07, 0x12, 0x37,
145 0x32, 0x29, 0x2d, 0x29, 0x25, 0x2b, 0x39, 0x00, 0x01,
146 0x03, 0x10);
147 mipi_dbi_command(dbi, ST7735R_GAMCTRN1, 0x03, 0x1d, 0x07, 0x06, 0x2e,
148 0x2c, 0x29, 0x2d, 0x2e, 0x2e, 0x37, 0x3f, 0x00, 0x00,
149 0x02, 0x10);
150 mipi_dbi_command(dbi, MIPI_DCS_SET_DISPLAY_ON);
151
152 msleep(100);
153
154 mipi_dbi_command(dbi, MIPI_DCS_ENTER_NORMAL_MODE);
155
156 msleep(20);
157
158 backlight_enable(dbidev->backlight);
159 out_exit:
160 drm_dev_exit(idx);
161 }
162
163 static const struct drm_crtc_helper_funcs st7735r_crtc_helper_funcs = {
164 DRM_MIPI_DBI_CRTC_HELPER_FUNCS,
165 .atomic_enable = st7735r_crtc_helper_atomic_enable,
166 };
167
168 static const struct drm_crtc_funcs st7735r_crtc_funcs = {
169 DRM_MIPI_DBI_CRTC_FUNCS,
170 .destroy = drm_crtc_cleanup,
171 };
172
173 static const struct drm_encoder_funcs st7735r_encoder_funcs = {
174 .destroy = drm_encoder_cleanup,
175 };
176
177 static const struct drm_connector_helper_funcs st7735r_connector_helper_funcs = {
178 DRM_MIPI_DBI_CONNECTOR_HELPER_FUNCS,
179 };
180
181 static const struct drm_connector_funcs st7735r_connector_funcs = {
182 DRM_MIPI_DBI_CONNECTOR_FUNCS,
183 .destroy = drm_connector_cleanup,
184 };
185
186 static const struct drm_mode_config_helper_funcs st7735r_mode_config_helper_funcs = {
187 DRM_MIPI_DBI_MODE_CONFIG_HELPER_FUNCS,
188 };
189
190 static const struct drm_mode_config_funcs st7735r_mode_config_funcs = {
191 DRM_MIPI_DBI_MODE_CONFIG_FUNCS,
192 };
193
194 static const struct st7735r_cfg jd_t18003_t01_cfg = {
195 .mode = { DRM_SIMPLE_MODE(128, 160, 28, 35) },
196 /* Cannot read from Adafruit 1.8" display via SPI */
197 .write_only = true,
198 };
199
200 static const struct st7735r_cfg rh128128t_cfg = {
201 .mode = { DRM_SIMPLE_MODE(128, 128, 25, 26) },
202 .left_offset = 2,
203 .top_offset = 3,
204 .rgb = true,
205 };
206
207 DEFINE_DRM_GEM_DMA_FOPS(st7735r_fops);
208
209 static const struct drm_driver st7735r_driver = {
210 .driver_features = DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC,
211 .fops = &st7735r_fops,
212 DRM_GEM_DMA_DRIVER_OPS_VMAP,
213 DRM_FBDEV_DMA_DRIVER_OPS,
214 .debugfs_init = mipi_dbi_debugfs_init,
215 .name = "st7735r",
216 .desc = "Sitronix ST7735R",
217 .major = 1,
218 .minor = 0,
219 };
220
221 static const struct of_device_id st7735r_of_match[] = {
222 { .compatible = "jianda,jd-t18003-t01", .data = &jd_t18003_t01_cfg },
223 { .compatible = "okaya,rh128128t", .data = &rh128128t_cfg },
224 { },
225 };
226 MODULE_DEVICE_TABLE(of, st7735r_of_match);
227
228 static const struct spi_device_id st7735r_id[] = {
229 { "jd-t18003-t01", (uintptr_t)&jd_t18003_t01_cfg },
230 { "rh128128t", (uintptr_t)&rh128128t_cfg },
231 { },
232 };
233 MODULE_DEVICE_TABLE(spi, st7735r_id);
234
st7735r_probe(struct spi_device * spi)235 static int st7735r_probe(struct spi_device *spi)
236 {
237 struct device *dev = &spi->dev;
238 const struct st7735r_cfg *cfg;
239 struct mipi_dbi_dev *dbidev;
240 struct st7735r_device *st7735r;
241 struct drm_device *drm;
242 struct mipi_dbi *dbi;
243 struct gpio_desc *dc;
244 struct drm_plane *plane;
245 struct drm_crtc *crtc;
246 struct drm_encoder *encoder;
247 struct drm_connector *connector;
248 u32 rotation = 0;
249 int ret;
250
251 cfg = device_get_match_data(&spi->dev);
252 if (!cfg)
253 cfg = (void *)spi_get_device_id(spi)->driver_data;
254
255 st7735r = devm_drm_dev_alloc(dev, &st7735r_driver, struct st7735r_device, dbidev.drm);
256 if (IS_ERR(st7735r))
257 return PTR_ERR(st7735r);
258
259 dbidev = &st7735r->dbidev;
260 st7735r->cfg = cfg;
261
262 dbi = &dbidev->dbi;
263 drm = &dbidev->drm;
264
265 dbi->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
266 if (IS_ERR(dbi->reset))
267 return dev_err_probe(dev, PTR_ERR(dbi->reset), "Failed to get GPIO 'reset'\n");
268
269 dc = devm_gpiod_get(dev, "dc", GPIOD_OUT_LOW);
270 if (IS_ERR(dc))
271 return dev_err_probe(dev, PTR_ERR(dc), "Failed to get GPIO 'dc'\n");
272
273 dbidev->backlight = devm_of_find_backlight(dev);
274 if (IS_ERR(dbidev->backlight))
275 return PTR_ERR(dbidev->backlight);
276
277 device_property_read_u32(dev, "rotation", &rotation);
278
279 ret = mipi_dbi_spi_init(spi, dbi, dc);
280 if (ret)
281 return ret;
282
283 if (cfg->write_only)
284 dbi->read_commands = NULL;
285
286 dbidev->left_offset = cfg->left_offset;
287 dbidev->top_offset = cfg->top_offset;
288
289 ret = drm_mipi_dbi_dev_init(dbidev, &cfg->mode, st7735r_plane_formats[0], rotation, 0);
290 if (ret)
291 return ret;
292
293 ret = drmm_mode_config_init(drm);
294 if (ret)
295 return ret;
296
297 drm->mode_config.min_width = dbidev->mode.hdisplay;
298 drm->mode_config.max_width = dbidev->mode.hdisplay;
299 drm->mode_config.min_height = dbidev->mode.vdisplay;
300 drm->mode_config.max_height = dbidev->mode.vdisplay;
301 drm->mode_config.funcs = &st7735r_mode_config_funcs;
302 drm->mode_config.preferred_depth = 16;
303 drm->mode_config.helper_private = &st7735r_mode_config_helper_funcs;
304
305 plane = &st7735r->plane;
306 ret = drm_universal_plane_init(drm, plane, 0, &st7735r_plane_funcs,
307 st7735r_plane_formats, ARRAY_SIZE(st7735r_plane_formats),
308 st7735r_plane_format_modifiers,
309 DRM_PLANE_TYPE_PRIMARY, NULL);
310 if (ret)
311 return ret;
312 drm_plane_helper_add(plane, &st7735r_plane_helper_funcs);
313 drm_plane_enable_fb_damage_clips(plane);
314
315 crtc = &st7735r->crtc;
316 ret = drm_crtc_init_with_planes(drm, crtc, plane, NULL, &st7735r_crtc_funcs, NULL);
317 if (ret)
318 return ret;
319 drm_crtc_helper_add(crtc, &st7735r_crtc_helper_funcs);
320
321 encoder = &st7735r->encoder;
322 ret = drm_encoder_init(drm, encoder, &st7735r_encoder_funcs, DRM_MODE_ENCODER_NONE, NULL);
323 if (ret)
324 return ret;
325 encoder->possible_crtcs = drm_crtc_mask(crtc);
326
327 connector = &st7735r->connector;
328 ret = drm_connector_init(drm, connector, &st7735r_connector_funcs,
329 DRM_MODE_CONNECTOR_SPI);
330 if (ret)
331 return ret;
332 drm_connector_helper_add(connector, &st7735r_connector_helper_funcs);
333
334 ret = drm_connector_attach_encoder(connector, encoder);
335 if (ret)
336 return ret;
337
338 drm_mode_config_reset(drm);
339
340 ret = drm_dev_register(drm, 0);
341 if (ret)
342 return ret;
343
344 spi_set_drvdata(spi, drm);
345
346 drm_client_setup(drm, NULL);
347
348 return 0;
349 }
350
st7735r_remove(struct spi_device * spi)351 static void st7735r_remove(struct spi_device *spi)
352 {
353 struct drm_device *drm = spi_get_drvdata(spi);
354
355 drm_dev_unplug(drm);
356 drm_atomic_helper_shutdown(drm);
357 }
358
st7735r_shutdown(struct spi_device * spi)359 static void st7735r_shutdown(struct spi_device *spi)
360 {
361 drm_atomic_helper_shutdown(spi_get_drvdata(spi));
362 }
363
364 static struct spi_driver st7735r_spi_driver = {
365 .driver = {
366 .name = "st7735r",
367 .of_match_table = st7735r_of_match,
368 },
369 .id_table = st7735r_id,
370 .probe = st7735r_probe,
371 .remove = st7735r_remove,
372 .shutdown = st7735r_shutdown,
373 };
374 module_spi_driver(st7735r_spi_driver);
375
376 MODULE_DESCRIPTION("Sitronix ST7735R DRM driver");
377 MODULE_AUTHOR("David Lechner <david@lechnology.com>");
378 MODULE_LICENSE("GPL");
379