1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2017 Free Electrons
4  */
5 
6 #include <linux/delay.h>
7 #include <linux/gpio/consumer.h>
8 #include <linux/module.h>
9 #include <linux/regulator/consumer.h>
10 #include <linux/spi/spi.h>
11 
12 #include <video/mipi_display.h>
13 
14 #include <drm/drm_device.h>
15 #include <drm/drm_modes.h>
16 #include <drm/drm_panel.h>
17 
18 #define ST7789V_COLMOD_RGB_FMT_18BITS		(6 << 4)
19 #define ST7789V_COLMOD_CTRL_FMT_18BITS		(6 << 0)
20 
21 #define ST7789V_RAMCTRL_CMD		0xb0
22 #define ST7789V_RAMCTRL_RM_RGB			BIT(4)
23 #define ST7789V_RAMCTRL_DM_RGB			BIT(0)
24 #define ST7789V_RAMCTRL_MAGIC			(3 << 6)
25 #define ST7789V_RAMCTRL_EPF(n)			(((n) & 3) << 4)
26 
27 #define ST7789V_RGBCTRL_CMD		0xb1
28 #define ST7789V_RGBCTRL_WO			BIT(7)
29 #define ST7789V_RGBCTRL_RCM(n)			(((n) & 3) << 5)
30 #define ST7789V_RGBCTRL_VSYNC_HIGH		BIT(3)
31 #define ST7789V_RGBCTRL_HSYNC_HIGH		BIT(2)
32 #define ST7789V_RGBCTRL_PCLK_HIGH		BIT(1)
33 #define ST7789V_RGBCTRL_VBP(n)			((n) & 0x7f)
34 #define ST7789V_RGBCTRL_HBP(n)			((n) & 0x1f)
35 
36 #define ST7789V_PORCTRL_CMD		0xb2
37 #define ST7789V_PORCTRL_IDLE_BP(n)		(((n) & 0xf) << 4)
38 #define ST7789V_PORCTRL_IDLE_FP(n)		((n) & 0xf)
39 #define ST7789V_PORCTRL_PARTIAL_BP(n)		(((n) & 0xf) << 4)
40 #define ST7789V_PORCTRL_PARTIAL_FP(n)		((n) & 0xf)
41 
42 #define ST7789V_GCTRL_CMD		0xb7
43 #define ST7789V_GCTRL_VGHS(n)			(((n) & 7) << 4)
44 #define ST7789V_GCTRL_VGLS(n)			((n) & 7)
45 
46 #define ST7789V_VCOMS_CMD		0xbb
47 
48 #define ST7789V_LCMCTRL_CMD		0xc0
49 #define ST7789V_LCMCTRL_XBGR			BIT(5)
50 #define ST7789V_LCMCTRL_XMX			BIT(3)
51 #define ST7789V_LCMCTRL_XMH			BIT(2)
52 
53 #define ST7789V_VDVVRHEN_CMD		0xc2
54 #define ST7789V_VDVVRHEN_CMDEN			BIT(0)
55 
56 #define ST7789V_VRHS_CMD		0xc3
57 
58 #define ST7789V_VDVS_CMD		0xc4
59 
60 #define ST7789V_FRCTRL2_CMD		0xc6
61 
62 #define ST7789V_PWCTRL1_CMD		0xd0
63 #define ST7789V_PWCTRL1_MAGIC			0xa4
64 #define ST7789V_PWCTRL1_AVDD(n)			(((n) & 3) << 6)
65 #define ST7789V_PWCTRL1_AVCL(n)			(((n) & 3) << 4)
66 #define ST7789V_PWCTRL1_VDS(n)			((n) & 3)
67 
68 #define ST7789V_PVGAMCTRL_CMD		0xe0
69 #define ST7789V_PVGAMCTRL_JP0(n)		(((n) & 3) << 4)
70 #define ST7789V_PVGAMCTRL_JP1(n)		(((n) & 3) << 4)
71 #define ST7789V_PVGAMCTRL_VP0(n)		((n) & 0xf)
72 #define ST7789V_PVGAMCTRL_VP1(n)		((n) & 0x3f)
73 #define ST7789V_PVGAMCTRL_VP2(n)		((n) & 0x3f)
74 #define ST7789V_PVGAMCTRL_VP4(n)		((n) & 0x1f)
75 #define ST7789V_PVGAMCTRL_VP6(n)		((n) & 0x1f)
76 #define ST7789V_PVGAMCTRL_VP13(n)		((n) & 0xf)
77 #define ST7789V_PVGAMCTRL_VP20(n)		((n) & 0x7f)
78 #define ST7789V_PVGAMCTRL_VP27(n)		((n) & 7)
79 #define ST7789V_PVGAMCTRL_VP36(n)		(((n) & 7) << 4)
80 #define ST7789V_PVGAMCTRL_VP43(n)		((n) & 0x7f)
81 #define ST7789V_PVGAMCTRL_VP50(n)		((n) & 0xf)
82 #define ST7789V_PVGAMCTRL_VP57(n)		((n) & 0x1f)
83 #define ST7789V_PVGAMCTRL_VP59(n)		((n) & 0x1f)
84 #define ST7789V_PVGAMCTRL_VP61(n)		((n) & 0x3f)
85 #define ST7789V_PVGAMCTRL_VP62(n)		((n) & 0x3f)
86 #define ST7789V_PVGAMCTRL_VP63(n)		(((n) & 0xf) << 4)
87 
88 #define ST7789V_NVGAMCTRL_CMD		0xe1
89 #define ST7789V_NVGAMCTRL_JN0(n)		(((n) & 3) << 4)
90 #define ST7789V_NVGAMCTRL_JN1(n)		(((n) & 3) << 4)
91 #define ST7789V_NVGAMCTRL_VN0(n)		((n) & 0xf)
92 #define ST7789V_NVGAMCTRL_VN1(n)		((n) & 0x3f)
93 #define ST7789V_NVGAMCTRL_VN2(n)		((n) & 0x3f)
94 #define ST7789V_NVGAMCTRL_VN4(n)		((n) & 0x1f)
95 #define ST7789V_NVGAMCTRL_VN6(n)		((n) & 0x1f)
96 #define ST7789V_NVGAMCTRL_VN13(n)		((n) & 0xf)
97 #define ST7789V_NVGAMCTRL_VN20(n)		((n) & 0x7f)
98 #define ST7789V_NVGAMCTRL_VN27(n)		((n) & 7)
99 #define ST7789V_NVGAMCTRL_VN36(n)		(((n) & 7) << 4)
100 #define ST7789V_NVGAMCTRL_VN43(n)		((n) & 0x7f)
101 #define ST7789V_NVGAMCTRL_VN50(n)		((n) & 0xf)
102 #define ST7789V_NVGAMCTRL_VN57(n)		((n) & 0x1f)
103 #define ST7789V_NVGAMCTRL_VN59(n)		((n) & 0x1f)
104 #define ST7789V_NVGAMCTRL_VN61(n)		((n) & 0x3f)
105 #define ST7789V_NVGAMCTRL_VN62(n)		((n) & 0x3f)
106 #define ST7789V_NVGAMCTRL_VN63(n)		(((n) & 0xf) << 4)
107 
108 #define ST7789V_TEST(val, func)			\
109 	do {					\
110 		if ((val = (func)))		\
111 			return val;		\
112 	} while (0)
113 
114 struct st7789v {
115 	struct drm_panel panel;
116 	struct spi_device *spi;
117 	struct gpio_desc *reset;
118 	struct regulator *power;
119 };
120 
121 enum st7789v_prefix {
122 	ST7789V_COMMAND = 0,
123 	ST7789V_DATA = 1,
124 };
125 
126 static inline struct st7789v *panel_to_st7789v(struct drm_panel *panel)
127 {
128 	return container_of(panel, struct st7789v, panel);
129 }
130 
131 static int st7789v_spi_write(struct st7789v *ctx, enum st7789v_prefix prefix,
132 			     u8 data)
133 {
134 	struct spi_transfer xfer = { };
135 	struct spi_message msg;
136 	u16 txbuf = ((prefix & 1) << 8) | data;
137 
138 	spi_message_init(&msg);
139 
140 	xfer.tx_buf = &txbuf;
141 	xfer.bits_per_word = 9;
142 	xfer.len = sizeof(txbuf);
143 
144 	spi_message_add_tail(&xfer, &msg);
145 	return spi_sync(ctx->spi, &msg);
146 }
147 
148 static int st7789v_write_command(struct st7789v *ctx, u8 cmd)
149 {
150 	return st7789v_spi_write(ctx, ST7789V_COMMAND, cmd);
151 }
152 
153 static int st7789v_write_data(struct st7789v *ctx, u8 cmd)
154 {
155 	return st7789v_spi_write(ctx, ST7789V_DATA, cmd);
156 }
157 
158 static const struct drm_display_mode default_mode = {
159 	.clock = 7000,
160 	.hdisplay = 240,
161 	.hsync_start = 240 + 38,
162 	.hsync_end = 240 + 38 + 10,
163 	.htotal = 240 + 38 + 10 + 10,
164 	.vdisplay = 320,
165 	.vsync_start = 320 + 8,
166 	.vsync_end = 320 + 8 + 4,
167 	.vtotal = 320 + 8 + 4 + 4,
168 };
169 
170 static int st7789v_get_modes(struct drm_panel *panel,
171 			     struct drm_connector *connector)
172 {
173 	struct drm_display_mode *mode;
174 
175 	mode = drm_mode_duplicate(connector->dev, &default_mode);
176 	if (!mode) {
177 		dev_err(panel->dev, "failed to add mode %ux%ux@%u\n",
178 			default_mode.hdisplay, default_mode.vdisplay,
179 			drm_mode_vrefresh(&default_mode));
180 		return -ENOMEM;
181 	}
182 
183 	drm_mode_set_name(mode);
184 
185 	mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
186 	drm_mode_probed_add(connector, mode);
187 
188 	connector->display_info.width_mm = 61;
189 	connector->display_info.height_mm = 103;
190 
191 	return 1;
192 }
193 
194 static int st7789v_prepare(struct drm_panel *panel)
195 {
196 	struct st7789v *ctx = panel_to_st7789v(panel);
197 	int ret;
198 
199 	ret = regulator_enable(ctx->power);
200 	if (ret)
201 		return ret;
202 
203 	gpiod_set_value(ctx->reset, 1);
204 	msleep(30);
205 	gpiod_set_value(ctx->reset, 0);
206 	msleep(120);
207 
208 	ST7789V_TEST(ret, st7789v_write_command(ctx, MIPI_DCS_EXIT_SLEEP_MODE));
209 
210 	/* We need to wait 120ms after a sleep out command */
211 	msleep(120);
212 
213 	ST7789V_TEST(ret, st7789v_write_command(ctx,
214 						MIPI_DCS_SET_ADDRESS_MODE));
215 	ST7789V_TEST(ret, st7789v_write_data(ctx, 0));
216 
217 	ST7789V_TEST(ret, st7789v_write_command(ctx,
218 						MIPI_DCS_SET_PIXEL_FORMAT));
219 	ST7789V_TEST(ret, st7789v_write_data(ctx,
220 					     (MIPI_DCS_PIXEL_FMT_18BIT << 4) |
221 					     (MIPI_DCS_PIXEL_FMT_18BIT)));
222 
223 	ST7789V_TEST(ret, st7789v_write_command(ctx, ST7789V_PORCTRL_CMD));
224 	ST7789V_TEST(ret, st7789v_write_data(ctx, 0xc));
225 	ST7789V_TEST(ret, st7789v_write_data(ctx, 0xc));
226 	ST7789V_TEST(ret, st7789v_write_data(ctx, 0));
227 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_PORCTRL_IDLE_BP(3) |
228 					     ST7789V_PORCTRL_IDLE_FP(3)));
229 	ST7789V_TEST(ret, st7789v_write_data(ctx,
230 					     ST7789V_PORCTRL_PARTIAL_BP(3) |
231 					     ST7789V_PORCTRL_PARTIAL_FP(3)));
232 
233 	ST7789V_TEST(ret, st7789v_write_command(ctx, ST7789V_GCTRL_CMD));
234 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_GCTRL_VGLS(5) |
235 					     ST7789V_GCTRL_VGHS(3)));
236 
237 	ST7789V_TEST(ret, st7789v_write_command(ctx, ST7789V_VCOMS_CMD));
238 	ST7789V_TEST(ret, st7789v_write_data(ctx, 0x2b));
239 
240 	ST7789V_TEST(ret, st7789v_write_command(ctx, ST7789V_LCMCTRL_CMD));
241 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_LCMCTRL_XMH |
242 					     ST7789V_LCMCTRL_XMX |
243 					     ST7789V_LCMCTRL_XBGR));
244 
245 	ST7789V_TEST(ret, st7789v_write_command(ctx, ST7789V_VDVVRHEN_CMD));
246 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_VDVVRHEN_CMDEN));
247 
248 	ST7789V_TEST(ret, st7789v_write_command(ctx, ST7789V_VRHS_CMD));
249 	ST7789V_TEST(ret, st7789v_write_data(ctx, 0xf));
250 
251 	ST7789V_TEST(ret, st7789v_write_command(ctx, ST7789V_VDVS_CMD));
252 	ST7789V_TEST(ret, st7789v_write_data(ctx, 0x20));
253 
254 	ST7789V_TEST(ret, st7789v_write_command(ctx, ST7789V_FRCTRL2_CMD));
255 	ST7789V_TEST(ret, st7789v_write_data(ctx, 0xf));
256 
257 	ST7789V_TEST(ret, st7789v_write_command(ctx, ST7789V_PWCTRL1_CMD));
258 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_PWCTRL1_MAGIC));
259 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_PWCTRL1_AVDD(2) |
260 					     ST7789V_PWCTRL1_AVCL(2) |
261 					     ST7789V_PWCTRL1_VDS(1)));
262 
263 	ST7789V_TEST(ret, st7789v_write_command(ctx, ST7789V_PVGAMCTRL_CMD));
264 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_PVGAMCTRL_VP63(0xd)));
265 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_PVGAMCTRL_VP1(0xca)));
266 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_PVGAMCTRL_VP2(0xe)));
267 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_PVGAMCTRL_VP4(8)));
268 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_PVGAMCTRL_VP6(9)));
269 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_PVGAMCTRL_VP13(7)));
270 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_PVGAMCTRL_VP20(0x2d)));
271 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_PVGAMCTRL_VP27(0xb) |
272 					     ST7789V_PVGAMCTRL_VP36(3)));
273 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_PVGAMCTRL_VP43(0x3d)));
274 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_PVGAMCTRL_JP1(3) |
275 					     ST7789V_PVGAMCTRL_VP50(4)));
276 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_PVGAMCTRL_VP57(0xa)));
277 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_PVGAMCTRL_VP59(0xa)));
278 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_PVGAMCTRL_VP61(0x1b)));
279 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_PVGAMCTRL_VP62(0x28)));
280 
281 	ST7789V_TEST(ret, st7789v_write_command(ctx, ST7789V_NVGAMCTRL_CMD));
282 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_NVGAMCTRL_VN63(0xd)));
283 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_NVGAMCTRL_VN1(0xca)));
284 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_NVGAMCTRL_VN2(0xf)));
285 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_NVGAMCTRL_VN4(8)));
286 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_NVGAMCTRL_VN6(8)));
287 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_NVGAMCTRL_VN13(7)));
288 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_NVGAMCTRL_VN20(0x2e)));
289 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_NVGAMCTRL_VN27(0xc) |
290 					     ST7789V_NVGAMCTRL_VN36(5)));
291 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_NVGAMCTRL_VN43(0x40)));
292 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_NVGAMCTRL_JN1(3) |
293 					     ST7789V_NVGAMCTRL_VN50(4)));
294 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_NVGAMCTRL_VN57(9)));
295 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_NVGAMCTRL_VN59(0xb)));
296 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_NVGAMCTRL_VN61(0x1b)));
297 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_NVGAMCTRL_VN62(0x28)));
298 
299 	ST7789V_TEST(ret, st7789v_write_command(ctx, MIPI_DCS_ENTER_INVERT_MODE));
300 
301 	ST7789V_TEST(ret, st7789v_write_command(ctx, ST7789V_RAMCTRL_CMD));
302 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_RAMCTRL_DM_RGB |
303 					     ST7789V_RAMCTRL_RM_RGB));
304 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_RAMCTRL_EPF(3) |
305 					     ST7789V_RAMCTRL_MAGIC));
306 
307 	ST7789V_TEST(ret, st7789v_write_command(ctx, ST7789V_RGBCTRL_CMD));
308 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_RGBCTRL_WO |
309 					     ST7789V_RGBCTRL_RCM(2) |
310 					     ST7789V_RGBCTRL_VSYNC_HIGH |
311 					     ST7789V_RGBCTRL_HSYNC_HIGH |
312 					     ST7789V_RGBCTRL_PCLK_HIGH));
313 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_RGBCTRL_VBP(8)));
314 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_RGBCTRL_HBP(20)));
315 
316 	return 0;
317 }
318 
319 static int st7789v_enable(struct drm_panel *panel)
320 {
321 	struct st7789v *ctx = panel_to_st7789v(panel);
322 
323 	return st7789v_write_command(ctx, MIPI_DCS_SET_DISPLAY_ON);
324 }
325 
326 static int st7789v_disable(struct drm_panel *panel)
327 {
328 	struct st7789v *ctx = panel_to_st7789v(panel);
329 	int ret;
330 
331 	ST7789V_TEST(ret, st7789v_write_command(ctx, MIPI_DCS_SET_DISPLAY_OFF));
332 
333 	return 0;
334 }
335 
336 static int st7789v_unprepare(struct drm_panel *panel)
337 {
338 	struct st7789v *ctx = panel_to_st7789v(panel);
339 	int ret;
340 
341 	ST7789V_TEST(ret, st7789v_write_command(ctx, MIPI_DCS_ENTER_SLEEP_MODE));
342 
343 	regulator_disable(ctx->power);
344 
345 	return 0;
346 }
347 
348 static const struct drm_panel_funcs st7789v_drm_funcs = {
349 	.disable	= st7789v_disable,
350 	.enable		= st7789v_enable,
351 	.get_modes	= st7789v_get_modes,
352 	.prepare	= st7789v_prepare,
353 	.unprepare	= st7789v_unprepare,
354 };
355 
356 static int st7789v_probe(struct spi_device *spi)
357 {
358 	struct st7789v *ctx;
359 	int ret;
360 
361 	ctx = devm_kzalloc(&spi->dev, sizeof(*ctx), GFP_KERNEL);
362 	if (!ctx)
363 		return -ENOMEM;
364 
365 	spi_set_drvdata(spi, ctx);
366 	ctx->spi = spi;
367 
368 	drm_panel_init(&ctx->panel, &spi->dev, &st7789v_drm_funcs,
369 		       DRM_MODE_CONNECTOR_DPI);
370 
371 	ctx->power = devm_regulator_get(&spi->dev, "power");
372 	if (IS_ERR(ctx->power))
373 		return PTR_ERR(ctx->power);
374 
375 	ctx->reset = devm_gpiod_get(&spi->dev, "reset", GPIOD_OUT_LOW);
376 	if (IS_ERR(ctx->reset)) {
377 		dev_err(&spi->dev, "Couldn't get our reset line\n");
378 		return PTR_ERR(ctx->reset);
379 	}
380 
381 	ret = drm_panel_of_backlight(&ctx->panel);
382 	if (ret)
383 		return ret;
384 
385 	drm_panel_add(&ctx->panel);
386 
387 	return 0;
388 }
389 
390 static int st7789v_remove(struct spi_device *spi)
391 {
392 	struct st7789v *ctx = spi_get_drvdata(spi);
393 
394 	drm_panel_remove(&ctx->panel);
395 
396 	return 0;
397 }
398 
399 static const struct of_device_id st7789v_of_match[] = {
400 	{ .compatible = "sitronix,st7789v" },
401 	{ }
402 };
403 MODULE_DEVICE_TABLE(of, st7789v_of_match);
404 
405 static struct spi_driver st7789v_driver = {
406 	.probe = st7789v_probe,
407 	.remove = st7789v_remove,
408 	.driver = {
409 		.name = "st7789v",
410 		.of_match_table = st7789v_of_match,
411 	},
412 };
413 module_spi_driver(st7789v_driver);
414 
415 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
416 MODULE_DESCRIPTION("Sitronix st7789v LCD Driver");
417 MODULE_LICENSE("GPL v2");
418