1 /*
2  * Copyright (C) 2017 Free Electrons
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License version
6  * 2 as published by the Free Software Foundation.
7  */
8 
9 #include <linux/gpio/consumer.h>
10 #include <linux/regulator/consumer.h>
11 #include <linux/spi/spi.h>
12 
13 #include <drm/drmP.h>
14 #include <drm/drm_panel.h>
15 
16 #include <video/mipi_display.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 backlight_device *backlight;
119 	struct regulator *power;
120 };
121 
122 enum st7789v_prefix {
123 	ST7789V_COMMAND = 0,
124 	ST7789V_DATA = 1,
125 };
126 
127 static inline struct st7789v *panel_to_st7789v(struct drm_panel *panel)
128 {
129 	return container_of(panel, struct st7789v, panel);
130 }
131 
132 static int st7789v_spi_write(struct st7789v *ctx, enum st7789v_prefix prefix,
133 			     u8 data)
134 {
135 	struct spi_transfer xfer = { };
136 	struct spi_message msg;
137 	u16 txbuf = ((prefix & 1) << 8) | data;
138 
139 	spi_message_init(&msg);
140 
141 	xfer.tx_buf = &txbuf;
142 	xfer.bits_per_word = 9;
143 	xfer.len = sizeof(txbuf);
144 
145 	spi_message_add_tail(&xfer, &msg);
146 	return spi_sync(ctx->spi, &msg);
147 }
148 
149 static int st7789v_write_command(struct st7789v *ctx, u8 cmd)
150 {
151 	return st7789v_spi_write(ctx, ST7789V_COMMAND, cmd);
152 }
153 
154 static int st7789v_write_data(struct st7789v *ctx, u8 cmd)
155 {
156 	return st7789v_spi_write(ctx, ST7789V_DATA, cmd);
157 }
158 
159 static const struct drm_display_mode default_mode = {
160 	.clock = 7000,
161 	.hdisplay = 240,
162 	.hsync_start = 240 + 38,
163 	.hsync_end = 240 + 38 + 10,
164 	.htotal = 240 + 38 + 10 + 10,
165 	.vdisplay = 320,
166 	.vsync_start = 320 + 8,
167 	.vsync_end = 320 + 8 + 4,
168 	.vtotal = 320 + 8 + 4 + 4,
169 	.vrefresh = 60,
170 };
171 
172 static int st7789v_get_modes(struct drm_panel *panel)
173 {
174 	struct drm_connector *connector = panel->connector;
175 	struct drm_display_mode *mode;
176 
177 	mode = drm_mode_duplicate(panel->drm, &default_mode);
178 	if (!mode) {
179 		dev_err(panel->drm->dev, "failed to add mode %ux%ux@%u\n",
180 			default_mode.hdisplay, default_mode.vdisplay,
181 			default_mode.vrefresh);
182 		return -ENOMEM;
183 	}
184 
185 	drm_mode_set_name(mode);
186 
187 	mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
188 	drm_mode_probed_add(connector, mode);
189 
190 	panel->connector->display_info.width_mm = 61;
191 	panel->connector->display_info.height_mm = 103;
192 
193 	return 1;
194 }
195 
196 static int st7789v_prepare(struct drm_panel *panel)
197 {
198 	struct st7789v *ctx = panel_to_st7789v(panel);
199 	int ret;
200 
201 	ret = regulator_enable(ctx->power);
202 	if (ret)
203 		return ret;
204 
205 	gpiod_set_value(ctx->reset, 1);
206 	msleep(30);
207 	gpiod_set_value(ctx->reset, 0);
208 	msleep(120);
209 
210 	ST7789V_TEST(ret, st7789v_write_command(ctx, MIPI_DCS_EXIT_SLEEP_MODE));
211 
212 	/* We need to wait 120ms after a sleep out command */
213 	msleep(120);
214 
215 	ST7789V_TEST(ret, st7789v_write_command(ctx,
216 						MIPI_DCS_SET_ADDRESS_MODE));
217 	ST7789V_TEST(ret, st7789v_write_data(ctx, 0));
218 
219 	ST7789V_TEST(ret, st7789v_write_command(ctx,
220 						MIPI_DCS_SET_PIXEL_FORMAT));
221 	ST7789V_TEST(ret, st7789v_write_data(ctx,
222 					     (MIPI_DCS_PIXEL_FMT_18BIT << 4) |
223 					     (MIPI_DCS_PIXEL_FMT_18BIT)));
224 
225 	ST7789V_TEST(ret, st7789v_write_command(ctx, ST7789V_PORCTRL_CMD));
226 	ST7789V_TEST(ret, st7789v_write_data(ctx, 0xc));
227 	ST7789V_TEST(ret, st7789v_write_data(ctx, 0xc));
228 	ST7789V_TEST(ret, st7789v_write_data(ctx, 0));
229 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_PORCTRL_IDLE_BP(3) |
230 					     ST7789V_PORCTRL_IDLE_FP(3)));
231 	ST7789V_TEST(ret, st7789v_write_data(ctx,
232 					     ST7789V_PORCTRL_PARTIAL_BP(3) |
233 					     ST7789V_PORCTRL_PARTIAL_FP(3)));
234 
235 	ST7789V_TEST(ret, st7789v_write_command(ctx, ST7789V_GCTRL_CMD));
236 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_GCTRL_VGLS(5) |
237 					     ST7789V_GCTRL_VGHS(3)));
238 
239 	ST7789V_TEST(ret, st7789v_write_command(ctx, ST7789V_VCOMS_CMD));
240 	ST7789V_TEST(ret, st7789v_write_data(ctx, 0x2b));
241 
242 	ST7789V_TEST(ret, st7789v_write_command(ctx, ST7789V_LCMCTRL_CMD));
243 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_LCMCTRL_XMH |
244 					     ST7789V_LCMCTRL_XMX |
245 					     ST7789V_LCMCTRL_XBGR));
246 
247 	ST7789V_TEST(ret, st7789v_write_command(ctx, ST7789V_VDVVRHEN_CMD));
248 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_VDVVRHEN_CMDEN));
249 
250 	ST7789V_TEST(ret, st7789v_write_command(ctx, ST7789V_VRHS_CMD));
251 	ST7789V_TEST(ret, st7789v_write_data(ctx, 0xf));
252 
253 	ST7789V_TEST(ret, st7789v_write_command(ctx, ST7789V_VDVS_CMD));
254 	ST7789V_TEST(ret, st7789v_write_data(ctx, 0x20));
255 
256 	ST7789V_TEST(ret, st7789v_write_command(ctx, ST7789V_FRCTRL2_CMD));
257 	ST7789V_TEST(ret, st7789v_write_data(ctx, 0xf));
258 
259 	ST7789V_TEST(ret, st7789v_write_command(ctx, ST7789V_PWCTRL1_CMD));
260 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_PWCTRL1_MAGIC));
261 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_PWCTRL1_AVDD(2) |
262 					     ST7789V_PWCTRL1_AVCL(2) |
263 					     ST7789V_PWCTRL1_VDS(1)));
264 
265 	ST7789V_TEST(ret, st7789v_write_command(ctx, ST7789V_PVGAMCTRL_CMD));
266 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_PVGAMCTRL_VP63(0xd)));
267 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_PVGAMCTRL_VP1(0xca)));
268 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_PVGAMCTRL_VP2(0xe)));
269 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_PVGAMCTRL_VP4(8)));
270 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_PVGAMCTRL_VP6(9)));
271 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_PVGAMCTRL_VP13(7)));
272 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_PVGAMCTRL_VP20(0x2d)));
273 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_PVGAMCTRL_VP27(0xb) |
274 					     ST7789V_PVGAMCTRL_VP36(3)));
275 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_PVGAMCTRL_VP43(0x3d)));
276 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_PVGAMCTRL_JP1(3) |
277 					     ST7789V_PVGAMCTRL_VP50(4)));
278 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_PVGAMCTRL_VP57(0xa)));
279 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_PVGAMCTRL_VP59(0xa)));
280 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_PVGAMCTRL_VP61(0x1b)));
281 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_PVGAMCTRL_VP62(0x28)));
282 
283 	ST7789V_TEST(ret, st7789v_write_command(ctx, ST7789V_NVGAMCTRL_CMD));
284 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_NVGAMCTRL_VN63(0xd)));
285 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_NVGAMCTRL_VN1(0xca)));
286 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_NVGAMCTRL_VN2(0xf)));
287 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_NVGAMCTRL_VN4(8)));
288 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_NVGAMCTRL_VN6(8)));
289 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_NVGAMCTRL_VN13(7)));
290 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_NVGAMCTRL_VN20(0x2e)));
291 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_NVGAMCTRL_VN27(0xc) |
292 					     ST7789V_NVGAMCTRL_VN36(5)));
293 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_NVGAMCTRL_VN43(0x40)));
294 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_NVGAMCTRL_JN1(3) |
295 					     ST7789V_NVGAMCTRL_VN50(4)));
296 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_NVGAMCTRL_VN57(9)));
297 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_NVGAMCTRL_VN59(0xb)));
298 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_NVGAMCTRL_VN61(0x1b)));
299 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_NVGAMCTRL_VN62(0x28)));
300 
301 	ST7789V_TEST(ret, st7789v_write_command(ctx, MIPI_DCS_ENTER_INVERT_MODE));
302 
303 	ST7789V_TEST(ret, st7789v_write_command(ctx, ST7789V_RAMCTRL_CMD));
304 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_RAMCTRL_DM_RGB |
305 					     ST7789V_RAMCTRL_RM_RGB));
306 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_RAMCTRL_EPF(3) |
307 					     ST7789V_RAMCTRL_MAGIC));
308 
309 	ST7789V_TEST(ret, st7789v_write_command(ctx, ST7789V_RGBCTRL_CMD));
310 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_RGBCTRL_WO |
311 					     ST7789V_RGBCTRL_RCM(2) |
312 					     ST7789V_RGBCTRL_VSYNC_HIGH |
313 					     ST7789V_RGBCTRL_HSYNC_HIGH |
314 					     ST7789V_RGBCTRL_PCLK_HIGH));
315 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_RGBCTRL_VBP(8)));
316 	ST7789V_TEST(ret, st7789v_write_data(ctx, ST7789V_RGBCTRL_HBP(20)));
317 
318 	return 0;
319 }
320 
321 static int st7789v_enable(struct drm_panel *panel)
322 {
323 	struct st7789v *ctx = panel_to_st7789v(panel);
324 
325 	if (ctx->backlight) {
326 		ctx->backlight->props.state &= ~BL_CORE_FBBLANK;
327 		ctx->backlight->props.power = FB_BLANK_UNBLANK;
328 		backlight_update_status(ctx->backlight);
329 	}
330 
331 	return st7789v_write_command(ctx, MIPI_DCS_SET_DISPLAY_ON);
332 }
333 
334 static int st7789v_disable(struct drm_panel *panel)
335 {
336 	struct st7789v *ctx = panel_to_st7789v(panel);
337 	int ret;
338 
339 	ST7789V_TEST(ret, st7789v_write_command(ctx, MIPI_DCS_SET_DISPLAY_OFF));
340 
341 	if (ctx->backlight) {
342 		ctx->backlight->props.power = FB_BLANK_POWERDOWN;
343 		ctx->backlight->props.state |= BL_CORE_FBBLANK;
344 		backlight_update_status(ctx->backlight);
345 	}
346 
347 	return 0;
348 }
349 
350 static int st7789v_unprepare(struct drm_panel *panel)
351 {
352 	struct st7789v *ctx = panel_to_st7789v(panel);
353 	int ret;
354 
355 	ST7789V_TEST(ret, st7789v_write_command(ctx, MIPI_DCS_ENTER_SLEEP_MODE));
356 
357 	regulator_disable(ctx->power);
358 
359 	return 0;
360 }
361 
362 static const struct drm_panel_funcs st7789v_drm_funcs = {
363 	.disable	= st7789v_disable,
364 	.enable		= st7789v_enable,
365 	.get_modes	= st7789v_get_modes,
366 	.prepare	= st7789v_prepare,
367 	.unprepare	= st7789v_unprepare,
368 };
369 
370 static int st7789v_probe(struct spi_device *spi)
371 {
372 	struct device_node *backlight;
373 	struct st7789v *ctx;
374 	int ret;
375 
376 	ctx = devm_kzalloc(&spi->dev, sizeof(*ctx), GFP_KERNEL);
377 	if (!ctx)
378 		return -ENOMEM;
379 
380 	spi_set_drvdata(spi, ctx);
381 	ctx->spi = spi;
382 
383 	ctx->panel.dev = &spi->dev;
384 	ctx->panel.funcs = &st7789v_drm_funcs;
385 
386 	ctx->power = devm_regulator_get(&spi->dev, "power");
387 	if (IS_ERR(ctx->power))
388 		return PTR_ERR(ctx->power);
389 
390 	ctx->reset = devm_gpiod_get(&spi->dev, "reset", GPIOD_OUT_LOW);
391 	if (IS_ERR(ctx->reset)) {
392 		dev_err(&spi->dev, "Couldn't get our reset line\n");
393 		return PTR_ERR(ctx->reset);
394 	}
395 
396 	backlight = of_parse_phandle(spi->dev.of_node, "backlight", 0);
397 	if (backlight) {
398 		ctx->backlight = of_find_backlight_by_node(backlight);
399 		of_node_put(backlight);
400 
401 		if (!ctx->backlight)
402 			return -EPROBE_DEFER;
403 	}
404 
405 	ret = drm_panel_add(&ctx->panel);
406 	if (ret < 0)
407 		goto err_free_backlight;
408 
409 	return 0;
410 
411 err_free_backlight:
412 	if (ctx->backlight)
413 		put_device(&ctx->backlight->dev);
414 
415 	return ret;
416 }
417 
418 static int st7789v_remove(struct spi_device *spi)
419 {
420 	struct st7789v *ctx = spi_get_drvdata(spi);
421 
422 	drm_panel_remove(&ctx->panel);
423 
424 	if (ctx->backlight)
425 		put_device(&ctx->backlight->dev);
426 
427 	return 0;
428 }
429 
430 static const struct of_device_id st7789v_of_match[] = {
431 	{ .compatible = "sitronix,st7789v" },
432 	{ }
433 };
434 MODULE_DEVICE_TABLE(of, st7789v_of_match);
435 
436 static struct spi_driver st7789v_driver = {
437 	.probe = st7789v_probe,
438 	.remove = st7789v_remove,
439 	.driver = {
440 		.name = "st7789v",
441 		.of_match_table = st7789v_of_match,
442 	},
443 };
444 module_spi_driver(st7789v_driver);
445 
446 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
447 MODULE_DESCRIPTION("Sitronix st7789v LCD Driver");
448 MODULE_LICENSE("GPL v2");
449