xref: /openbmc/linux/drivers/gpu/drm/solomon/ssd130x.c (revision 050bb587)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * DRM driver for Solomon SSD130x OLED displays
4  *
5  * Copyright 2022 Red Hat Inc.
6  * Author: Javier Martinez Canillas <javierm@redhat.com>
7  *
8  * Based on drivers/video/fbdev/ssd1307fb.c
9  * Copyright 2012 Free Electrons
10  */
11 
12 #include <linux/backlight.h>
13 #include <linux/bitfield.h>
14 #include <linux/bits.h>
15 #include <linux/delay.h>
16 #include <linux/gpio/consumer.h>
17 #include <linux/property.h>
18 #include <linux/pwm.h>
19 #include <linux/regulator/consumer.h>
20 
21 #include <drm/drm_atomic.h>
22 #include <drm/drm_atomic_helper.h>
23 #include <drm/drm_crtc_helper.h>
24 #include <drm/drm_damage_helper.h>
25 #include <drm/drm_edid.h>
26 #include <drm/drm_fbdev_generic.h>
27 #include <drm/drm_format_helper.h>
28 #include <drm/drm_framebuffer.h>
29 #include <drm/drm_gem_atomic_helper.h>
30 #include <drm/drm_gem_framebuffer_helper.h>
31 #include <drm/drm_gem_shmem_helper.h>
32 #include <drm/drm_managed.h>
33 #include <drm/drm_modes.h>
34 #include <drm/drm_rect.h>
35 #include <drm/drm_probe_helper.h>
36 
37 #include "ssd130x.h"
38 
39 #define DRIVER_NAME	"ssd130x"
40 #define DRIVER_DESC	"DRM driver for Solomon SSD130x OLED displays"
41 #define DRIVER_DATE	"20220131"
42 #define DRIVER_MAJOR	1
43 #define DRIVER_MINOR	0
44 
45 #define SSD130X_PAGE_COL_START_LOW		0x00
46 #define SSD130X_PAGE_COL_START_HIGH		0x10
47 #define SSD130X_SET_ADDRESS_MODE		0x20
48 #define SSD130X_SET_COL_RANGE			0x21
49 #define SSD130X_SET_PAGE_RANGE			0x22
50 #define SSD130X_CONTRAST			0x81
51 #define SSD130X_SET_LOOKUP_TABLE		0x91
52 #define SSD130X_CHARGE_PUMP			0x8d
53 #define SSD130X_SET_SEG_REMAP			0xa0
54 #define SSD130X_DISPLAY_OFF			0xae
55 #define SSD130X_SET_MULTIPLEX_RATIO		0xa8
56 #define SSD130X_DISPLAY_ON			0xaf
57 #define SSD130X_START_PAGE_ADDRESS		0xb0
58 #define SSD130X_SET_COM_SCAN_DIR		0xc0
59 #define SSD130X_SET_DISPLAY_OFFSET		0xd3
60 #define SSD130X_SET_CLOCK_FREQ			0xd5
61 #define SSD130X_SET_AREA_COLOR_MODE		0xd8
62 #define SSD130X_SET_PRECHARGE_PERIOD		0xd9
63 #define SSD130X_SET_COM_PINS_CONFIG		0xda
64 #define SSD130X_SET_VCOMH			0xdb
65 
66 #define SSD130X_PAGE_COL_START_MASK		GENMASK(3, 0)
67 #define SSD130X_PAGE_COL_START_HIGH_SET(val)	FIELD_PREP(SSD130X_PAGE_COL_START_MASK, (val) >> 4)
68 #define SSD130X_PAGE_COL_START_LOW_SET(val)	FIELD_PREP(SSD130X_PAGE_COL_START_MASK, (val))
69 #define SSD130X_START_PAGE_ADDRESS_MASK		GENMASK(2, 0)
70 #define SSD130X_START_PAGE_ADDRESS_SET(val)	FIELD_PREP(SSD130X_START_PAGE_ADDRESS_MASK, (val))
71 #define SSD130X_SET_SEG_REMAP_MASK		GENMASK(0, 0)
72 #define SSD130X_SET_SEG_REMAP_SET(val)		FIELD_PREP(SSD130X_SET_SEG_REMAP_MASK, (val))
73 #define SSD130X_SET_COM_SCAN_DIR_MASK		GENMASK(3, 3)
74 #define SSD130X_SET_COM_SCAN_DIR_SET(val)	FIELD_PREP(SSD130X_SET_COM_SCAN_DIR_MASK, (val))
75 #define SSD130X_SET_CLOCK_DIV_MASK		GENMASK(3, 0)
76 #define SSD130X_SET_CLOCK_DIV_SET(val)		FIELD_PREP(SSD130X_SET_CLOCK_DIV_MASK, (val))
77 #define SSD130X_SET_CLOCK_FREQ_MASK		GENMASK(7, 4)
78 #define SSD130X_SET_CLOCK_FREQ_SET(val)		FIELD_PREP(SSD130X_SET_CLOCK_FREQ_MASK, (val))
79 #define SSD130X_SET_PRECHARGE_PERIOD1_MASK	GENMASK(3, 0)
80 #define SSD130X_SET_PRECHARGE_PERIOD1_SET(val)	FIELD_PREP(SSD130X_SET_PRECHARGE_PERIOD1_MASK, (val))
81 #define SSD130X_SET_PRECHARGE_PERIOD2_MASK	GENMASK(7, 4)
82 #define SSD130X_SET_PRECHARGE_PERIOD2_SET(val)	FIELD_PREP(SSD130X_SET_PRECHARGE_PERIOD2_MASK, (val))
83 #define SSD130X_SET_COM_PINS_CONFIG1_MASK	GENMASK(4, 4)
84 #define SSD130X_SET_COM_PINS_CONFIG1_SET(val)	FIELD_PREP(SSD130X_SET_COM_PINS_CONFIG1_MASK, (val))
85 #define SSD130X_SET_COM_PINS_CONFIG2_MASK	GENMASK(5, 5)
86 #define SSD130X_SET_COM_PINS_CONFIG2_SET(val)	FIELD_PREP(SSD130X_SET_COM_PINS_CONFIG2_MASK, (val))
87 
88 #define SSD130X_SET_ADDRESS_MODE_HORIZONTAL	0x00
89 #define SSD130X_SET_ADDRESS_MODE_VERTICAL	0x01
90 #define SSD130X_SET_ADDRESS_MODE_PAGE		0x02
91 
92 #define SSD130X_SET_AREA_COLOR_MODE_ENABLE	0x1e
93 #define SSD130X_SET_AREA_COLOR_MODE_LOW_POWER	0x05
94 
95 #define MAX_CONTRAST 255
96 
97 const struct ssd130x_deviceinfo ssd130x_variants[] = {
98 	[SH1106_ID] = {
99 		.default_vcomh = 0x40,
100 		.default_dclk_div = 1,
101 		.default_dclk_frq = 5,
102 		.default_width = 132,
103 		.default_height = 64,
104 		.page_mode_only = 1,
105 		.page_height = 8,
106 	},
107 	[SSD1305_ID] = {
108 		.default_vcomh = 0x34,
109 		.default_dclk_div = 1,
110 		.default_dclk_frq = 7,
111 		.default_width = 132,
112 		.default_height = 64,
113 		.page_height = 8,
114 	},
115 	[SSD1306_ID] = {
116 		.default_vcomh = 0x20,
117 		.default_dclk_div = 1,
118 		.default_dclk_frq = 8,
119 		.need_chargepump = 1,
120 		.default_width = 128,
121 		.default_height = 64,
122 		.page_height = 8,
123 	},
124 	[SSD1307_ID] = {
125 		.default_vcomh = 0x20,
126 		.default_dclk_div = 2,
127 		.default_dclk_frq = 12,
128 		.need_pwm = 1,
129 		.default_width = 128,
130 		.default_height = 39,
131 		.page_height = 8,
132 	},
133 	[SSD1309_ID] = {
134 		.default_vcomh = 0x34,
135 		.default_dclk_div = 1,
136 		.default_dclk_frq = 10,
137 		.default_width = 128,
138 		.default_height = 64,
139 		.page_height = 8,
140 	}
141 };
142 EXPORT_SYMBOL_NS_GPL(ssd130x_variants, DRM_SSD130X);
143 
144 static inline struct ssd130x_device *drm_to_ssd130x(struct drm_device *drm)
145 {
146 	return container_of(drm, struct ssd130x_device, drm);
147 }
148 
149 static int ssd130x_buf_alloc(struct ssd130x_device *ssd130x)
150 {
151 	unsigned int page_height = ssd130x->device_info->page_height;
152 	unsigned int pages = DIV_ROUND_UP(ssd130x->height, page_height);
153 	const struct drm_format_info *fi;
154 	unsigned int pitch;
155 
156 	fi = drm_format_info(DRM_FORMAT_R1);
157 	if (!fi)
158 		return -EINVAL;
159 
160 	pitch = drm_format_info_min_pitch(fi, 0, ssd130x->width);
161 
162 	ssd130x->buffer = kcalloc(pitch, ssd130x->height, GFP_KERNEL);
163 	if (!ssd130x->buffer)
164 		return -ENOMEM;
165 
166 	ssd130x->data_array = kcalloc(ssd130x->width, pages, GFP_KERNEL);
167 	if (!ssd130x->data_array) {
168 		kfree(ssd130x->buffer);
169 		return -ENOMEM;
170 	}
171 
172 	return 0;
173 }
174 
175 static void ssd130x_buf_free(struct ssd130x_device *ssd130x)
176 {
177 	kfree(ssd130x->data_array);
178 	kfree(ssd130x->buffer);
179 }
180 
181 /*
182  * Helper to write data (SSD130X_DATA) to the device.
183  */
184 static int ssd130x_write_data(struct ssd130x_device *ssd130x, u8 *values, int count)
185 {
186 	return regmap_bulk_write(ssd130x->regmap, SSD130X_DATA, values, count);
187 }
188 
189 /*
190  * Helper to write command (SSD130X_COMMAND). The fist variadic argument
191  * is the command to write and the following are the command options.
192  *
193  * Note that the ssd130x protocol requires each command and option to be
194  * written as a SSD130X_COMMAND device register value. That is why a call
195  * to regmap_write(..., SSD130X_COMMAND, ...) is done for each argument.
196  */
197 static int ssd130x_write_cmd(struct ssd130x_device *ssd130x, int count,
198 			     /* u8 cmd, u8 option, ... */...)
199 {
200 	va_list ap;
201 	u8 value;
202 	int ret;
203 
204 	va_start(ap, count);
205 
206 	do {
207 		value = va_arg(ap, int);
208 		ret = regmap_write(ssd130x->regmap, SSD130X_COMMAND, value);
209 		if (ret)
210 			goto out_end;
211 	} while (--count);
212 
213 out_end:
214 	va_end(ap);
215 
216 	return ret;
217 }
218 
219 /* Set address range for horizontal/vertical addressing modes */
220 static int ssd130x_set_col_range(struct ssd130x_device *ssd130x,
221 				 u8 col_start, u8 cols)
222 {
223 	u8 col_end = col_start + cols - 1;
224 	int ret;
225 
226 	if (col_start == ssd130x->col_start && col_end == ssd130x->col_end)
227 		return 0;
228 
229 	ret = ssd130x_write_cmd(ssd130x, 3, SSD130X_SET_COL_RANGE, col_start, col_end);
230 	if (ret < 0)
231 		return ret;
232 
233 	ssd130x->col_start = col_start;
234 	ssd130x->col_end = col_end;
235 	return 0;
236 }
237 
238 static int ssd130x_set_page_range(struct ssd130x_device *ssd130x,
239 				  u8 page_start, u8 pages)
240 {
241 	u8 page_end = page_start + pages - 1;
242 	int ret;
243 
244 	if (page_start == ssd130x->page_start && page_end == ssd130x->page_end)
245 		return 0;
246 
247 	ret = ssd130x_write_cmd(ssd130x, 3, SSD130X_SET_PAGE_RANGE, page_start, page_end);
248 	if (ret < 0)
249 		return ret;
250 
251 	ssd130x->page_start = page_start;
252 	ssd130x->page_end = page_end;
253 	return 0;
254 }
255 
256 /* Set page and column start address for page addressing mode */
257 static int ssd130x_set_page_pos(struct ssd130x_device *ssd130x,
258 				u8 page_start, u8 col_start)
259 {
260 	int ret;
261 	u32 page, col_low, col_high;
262 
263 	page = SSD130X_START_PAGE_ADDRESS |
264 	       SSD130X_START_PAGE_ADDRESS_SET(page_start);
265 	col_low = SSD130X_PAGE_COL_START_LOW |
266 		  SSD130X_PAGE_COL_START_LOW_SET(col_start);
267 	col_high = SSD130X_PAGE_COL_START_HIGH |
268 		   SSD130X_PAGE_COL_START_HIGH_SET(col_start);
269 	ret = ssd130x_write_cmd(ssd130x, 3, page, col_low, col_high);
270 	if (ret < 0)
271 		return ret;
272 
273 	return 0;
274 }
275 
276 static int ssd130x_pwm_enable(struct ssd130x_device *ssd130x)
277 {
278 	struct device *dev = ssd130x->dev;
279 	struct pwm_state pwmstate;
280 
281 	ssd130x->pwm = pwm_get(dev, NULL);
282 	if (IS_ERR(ssd130x->pwm)) {
283 		dev_err(dev, "Could not get PWM from firmware description!\n");
284 		return PTR_ERR(ssd130x->pwm);
285 	}
286 
287 	pwm_init_state(ssd130x->pwm, &pwmstate);
288 	pwm_set_relative_duty_cycle(&pwmstate, 50, 100);
289 	pwm_apply_state(ssd130x->pwm, &pwmstate);
290 
291 	/* Enable the PWM */
292 	pwm_enable(ssd130x->pwm);
293 
294 	dev_dbg(dev, "Using PWM%d with a %lluns period.\n",
295 		ssd130x->pwm->pwm, pwm_get_period(ssd130x->pwm));
296 
297 	return 0;
298 }
299 
300 static void ssd130x_reset(struct ssd130x_device *ssd130x)
301 {
302 	if (!ssd130x->reset)
303 		return;
304 
305 	/* Reset the screen */
306 	gpiod_set_value_cansleep(ssd130x->reset, 1);
307 	udelay(4);
308 	gpiod_set_value_cansleep(ssd130x->reset, 0);
309 	udelay(4);
310 }
311 
312 static int ssd130x_power_on(struct ssd130x_device *ssd130x)
313 {
314 	struct device *dev = ssd130x->dev;
315 	int ret;
316 
317 	ssd130x_reset(ssd130x);
318 
319 	ret = regulator_enable(ssd130x->vcc_reg);
320 	if (ret) {
321 		dev_err(dev, "Failed to enable VCC: %d\n", ret);
322 		return ret;
323 	}
324 
325 	if (ssd130x->device_info->need_pwm) {
326 		ret = ssd130x_pwm_enable(ssd130x);
327 		if (ret) {
328 			dev_err(dev, "Failed to enable PWM: %d\n", ret);
329 			regulator_disable(ssd130x->vcc_reg);
330 			return ret;
331 		}
332 	}
333 
334 	return 0;
335 }
336 
337 static void ssd130x_power_off(struct ssd130x_device *ssd130x)
338 {
339 	pwm_disable(ssd130x->pwm);
340 	pwm_put(ssd130x->pwm);
341 
342 	regulator_disable(ssd130x->vcc_reg);
343 }
344 
345 static int ssd130x_init(struct ssd130x_device *ssd130x)
346 {
347 	u32 precharge, dclk, com_invdir, compins, chargepump, seg_remap;
348 	bool scan_mode;
349 	int ret;
350 
351 	/* Set initial contrast */
352 	ret = ssd130x_write_cmd(ssd130x, 2, SSD130X_CONTRAST, ssd130x->contrast);
353 	if (ret < 0)
354 		return ret;
355 
356 	/* Set segment re-map */
357 	seg_remap = (SSD130X_SET_SEG_REMAP |
358 		     SSD130X_SET_SEG_REMAP_SET(ssd130x->seg_remap));
359 	ret = ssd130x_write_cmd(ssd130x, 1, seg_remap);
360 	if (ret < 0)
361 		return ret;
362 
363 	/* Set COM direction */
364 	com_invdir = (SSD130X_SET_COM_SCAN_DIR |
365 		      SSD130X_SET_COM_SCAN_DIR_SET(ssd130x->com_invdir));
366 	ret = ssd130x_write_cmd(ssd130x,  1, com_invdir);
367 	if (ret < 0)
368 		return ret;
369 
370 	/* Set multiplex ratio value */
371 	ret = ssd130x_write_cmd(ssd130x, 2, SSD130X_SET_MULTIPLEX_RATIO, ssd130x->height - 1);
372 	if (ret < 0)
373 		return ret;
374 
375 	/* set display offset value */
376 	ret = ssd130x_write_cmd(ssd130x, 2, SSD130X_SET_DISPLAY_OFFSET, ssd130x->com_offset);
377 	if (ret < 0)
378 		return ret;
379 
380 	/* Set clock frequency */
381 	dclk = (SSD130X_SET_CLOCK_DIV_SET(ssd130x->dclk_div - 1) |
382 		SSD130X_SET_CLOCK_FREQ_SET(ssd130x->dclk_frq));
383 	ret = ssd130x_write_cmd(ssd130x, 2, SSD130X_SET_CLOCK_FREQ, dclk);
384 	if (ret < 0)
385 		return ret;
386 
387 	/* Set Area Color Mode ON/OFF & Low Power Display Mode */
388 	if (ssd130x->area_color_enable || ssd130x->low_power) {
389 		u32 mode = 0;
390 
391 		if (ssd130x->area_color_enable)
392 			mode |= SSD130X_SET_AREA_COLOR_MODE_ENABLE;
393 
394 		if (ssd130x->low_power)
395 			mode |= SSD130X_SET_AREA_COLOR_MODE_LOW_POWER;
396 
397 		ret = ssd130x_write_cmd(ssd130x, 2, SSD130X_SET_AREA_COLOR_MODE, mode);
398 		if (ret < 0)
399 			return ret;
400 	}
401 
402 	/* Set precharge period in number of ticks from the internal clock */
403 	precharge = (SSD130X_SET_PRECHARGE_PERIOD1_SET(ssd130x->prechargep1) |
404 		     SSD130X_SET_PRECHARGE_PERIOD2_SET(ssd130x->prechargep2));
405 	ret = ssd130x_write_cmd(ssd130x, 2, SSD130X_SET_PRECHARGE_PERIOD, precharge);
406 	if (ret < 0)
407 		return ret;
408 
409 	/* Set COM pins configuration */
410 	compins = BIT(1);
411 	/*
412 	 * The COM scan mode field values are the inverse of the boolean DT
413 	 * property "solomon,com-seq". The value 0b means scan from COM0 to
414 	 * COM[N - 1] while 1b means scan from COM[N - 1] to COM0.
415 	 */
416 	scan_mode = !ssd130x->com_seq;
417 	compins |= (SSD130X_SET_COM_PINS_CONFIG1_SET(scan_mode) |
418 		    SSD130X_SET_COM_PINS_CONFIG2_SET(ssd130x->com_lrremap));
419 	ret = ssd130x_write_cmd(ssd130x, 2, SSD130X_SET_COM_PINS_CONFIG, compins);
420 	if (ret < 0)
421 		return ret;
422 
423 	/* Set VCOMH */
424 	ret = ssd130x_write_cmd(ssd130x, 2, SSD130X_SET_VCOMH, ssd130x->vcomh);
425 	if (ret < 0)
426 		return ret;
427 
428 	/* Turn on the DC-DC Charge Pump */
429 	chargepump = BIT(4);
430 
431 	if (ssd130x->device_info->need_chargepump)
432 		chargepump |= BIT(2);
433 
434 	ret = ssd130x_write_cmd(ssd130x, 2, SSD130X_CHARGE_PUMP, chargepump);
435 	if (ret < 0)
436 		return ret;
437 
438 	/* Set lookup table */
439 	if (ssd130x->lookup_table_set) {
440 		int i;
441 
442 		ret = ssd130x_write_cmd(ssd130x, 1, SSD130X_SET_LOOKUP_TABLE);
443 		if (ret < 0)
444 			return ret;
445 
446 		for (i = 0; i < ARRAY_SIZE(ssd130x->lookup_table); i++) {
447 			u8 val = ssd130x->lookup_table[i];
448 
449 			if (val < 31 || val > 63)
450 				dev_warn(ssd130x->dev,
451 					 "lookup table index %d value out of range 31 <= %d <= 63\n",
452 					 i, val);
453 			ret = ssd130x_write_cmd(ssd130x, 1, val);
454 			if (ret < 0)
455 				return ret;
456 		}
457 	}
458 
459 	/* Switch to page addressing mode */
460 	if (ssd130x->page_address_mode)
461 		return ssd130x_write_cmd(ssd130x, 2, SSD130X_SET_ADDRESS_MODE,
462 					 SSD130X_SET_ADDRESS_MODE_PAGE);
463 
464 	/* Switch to horizontal addressing mode */
465 	return ssd130x_write_cmd(ssd130x, 2, SSD130X_SET_ADDRESS_MODE,
466 				 SSD130X_SET_ADDRESS_MODE_HORIZONTAL);
467 }
468 
469 static int ssd130x_update_rect(struct ssd130x_device *ssd130x, struct drm_rect *rect)
470 {
471 	unsigned int x = rect->x1;
472 	unsigned int y = rect->y1;
473 	u8 *buf = ssd130x->buffer;
474 	u8 *data_array = ssd130x->data_array;
475 	unsigned int width = drm_rect_width(rect);
476 	unsigned int height = drm_rect_height(rect);
477 	unsigned int line_length = DIV_ROUND_UP(width, 8);
478 	unsigned int page_height = ssd130x->device_info->page_height;
479 	unsigned int pages = DIV_ROUND_UP(height, page_height);
480 	struct drm_device *drm = &ssd130x->drm;
481 	u32 array_idx = 0;
482 	int ret, i, j, k;
483 
484 	drm_WARN_ONCE(drm, y % 8 != 0, "y must be aligned to screen page\n");
485 
486 	/*
487 	 * The screen is divided in pages, each having a height of 8
488 	 * pixels, and the width of the screen. When sending a byte of
489 	 * data to the controller, it gives the 8 bits for the current
490 	 * column. I.e, the first byte are the 8 bits of the first
491 	 * column, then the 8 bits for the second column, etc.
492 	 *
493 	 *
494 	 * Representation of the screen, assuming it is 5 bits
495 	 * wide. Each letter-number combination is a bit that controls
496 	 * one pixel.
497 	 *
498 	 * A0 A1 A2 A3 A4
499 	 * B0 B1 B2 B3 B4
500 	 * C0 C1 C2 C3 C4
501 	 * D0 D1 D2 D3 D4
502 	 * E0 E1 E2 E3 E4
503 	 * F0 F1 F2 F3 F4
504 	 * G0 G1 G2 G3 G4
505 	 * H0 H1 H2 H3 H4
506 	 *
507 	 * If you want to update this screen, you need to send 5 bytes:
508 	 *  (1) A0 B0 C0 D0 E0 F0 G0 H0
509 	 *  (2) A1 B1 C1 D1 E1 F1 G1 H1
510 	 *  (3) A2 B2 C2 D2 E2 F2 G2 H2
511 	 *  (4) A3 B3 C3 D3 E3 F3 G3 H3
512 	 *  (5) A4 B4 C4 D4 E4 F4 G4 H4
513 	 */
514 
515 	if (!ssd130x->page_address_mode) {
516 		/* Set address range for horizontal addressing mode */
517 		ret = ssd130x_set_col_range(ssd130x, ssd130x->col_offset + x, width);
518 		if (ret < 0)
519 			return ret;
520 
521 		ret = ssd130x_set_page_range(ssd130x, ssd130x->page_offset + y / 8, pages);
522 		if (ret < 0)
523 			return ret;
524 	}
525 
526 	for (i = 0; i < pages; i++) {
527 		int m = 8;
528 
529 		/* Last page may be partial */
530 		if (8 * (y / 8 + i + 1) > ssd130x->height)
531 			m = ssd130x->height % 8;
532 		for (j = 0; j < width; j++) {
533 			u8 data = 0;
534 
535 			for (k = 0; k < m; k++) {
536 				u8 byte = buf[(8 * i + k) * line_length + j / 8];
537 				u8 bit = (byte >> (j % 8)) & 1;
538 
539 				data |= bit << k;
540 			}
541 			data_array[array_idx++] = data;
542 		}
543 
544 		/*
545 		 * In page addressing mode, the start address needs to be reset,
546 		 * and each page then needs to be written out separately.
547 		 */
548 		if (ssd130x->page_address_mode) {
549 			ret = ssd130x_set_page_pos(ssd130x,
550 						   ssd130x->page_offset + i,
551 						   ssd130x->col_offset + x);
552 			if (ret < 0)
553 				return ret;
554 
555 			ret = ssd130x_write_data(ssd130x, data_array, width);
556 			if (ret < 0)
557 				return ret;
558 
559 			array_idx = 0;
560 		}
561 	}
562 
563 	/* Write out update in one go if we aren't using page addressing mode */
564 	if (!ssd130x->page_address_mode)
565 		ret = ssd130x_write_data(ssd130x, data_array, width * pages);
566 
567 	return ret;
568 }
569 
570 static void ssd130x_clear_screen(struct ssd130x_device *ssd130x)
571 {
572 	struct drm_rect fullscreen = {
573 		.x1 = 0,
574 		.x2 = ssd130x->width,
575 		.y1 = 0,
576 		.y2 = ssd130x->height,
577 	};
578 
579 	ssd130x_update_rect(ssd130x, &fullscreen);
580 }
581 
582 static int ssd130x_fb_blit_rect(struct drm_framebuffer *fb, const struct iosys_map *vmap,
583 				struct drm_rect *rect)
584 {
585 	struct ssd130x_device *ssd130x = drm_to_ssd130x(fb->dev);
586 	unsigned int page_height = ssd130x->device_info->page_height;
587 	struct iosys_map dst;
588 	unsigned int dst_pitch;
589 	int ret = 0;
590 	u8 *buf = ssd130x->buffer;
591 
592 	if (!buf)
593 		return 0;
594 
595 	/* Align y to display page boundaries */
596 	rect->y1 = round_down(rect->y1, page_height);
597 	rect->y2 = min_t(unsigned int, round_up(rect->y2, page_height), ssd130x->height);
598 
599 	dst_pitch = DIV_ROUND_UP(drm_rect_width(rect), 8);
600 
601 	ret = drm_gem_fb_begin_cpu_access(fb, DMA_FROM_DEVICE);
602 	if (ret)
603 		return ret;
604 
605 	iosys_map_set_vaddr(&dst, buf);
606 	drm_fb_xrgb8888_to_mono(&dst, &dst_pitch, vmap, fb, rect);
607 
608 	drm_gem_fb_end_cpu_access(fb, DMA_FROM_DEVICE);
609 
610 	ssd130x_update_rect(ssd130x, rect);
611 
612 	return ret;
613 }
614 
615 static void ssd130x_primary_plane_helper_atomic_update(struct drm_plane *plane,
616 						       struct drm_atomic_state *state)
617 {
618 	struct drm_plane_state *plane_state = drm_atomic_get_new_plane_state(state, plane);
619 	struct drm_plane_state *old_plane_state = drm_atomic_get_old_plane_state(state, plane);
620 	struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(plane_state);
621 	struct drm_atomic_helper_damage_iter iter;
622 	struct drm_device *drm = plane->dev;
623 	struct drm_rect dst_clip;
624 	struct drm_rect damage;
625 	int idx;
626 
627 	if (!drm_dev_enter(drm, &idx))
628 		return;
629 
630 	drm_atomic_helper_damage_iter_init(&iter, old_plane_state, plane_state);
631 	drm_atomic_for_each_plane_damage(&iter, &damage) {
632 		dst_clip = plane_state->dst;
633 
634 		if (!drm_rect_intersect(&dst_clip, &damage))
635 			continue;
636 
637 		ssd130x_fb_blit_rect(plane_state->fb, &shadow_plane_state->data[0], &dst_clip);
638 	}
639 
640 	drm_dev_exit(idx);
641 }
642 
643 static void ssd130x_primary_plane_helper_atomic_disable(struct drm_plane *plane,
644 							struct drm_atomic_state *state)
645 {
646 	struct drm_device *drm = plane->dev;
647 	struct ssd130x_device *ssd130x = drm_to_ssd130x(drm);
648 	int idx;
649 
650 	if (!drm_dev_enter(drm, &idx))
651 		return;
652 
653 	ssd130x_clear_screen(ssd130x);
654 
655 	drm_dev_exit(idx);
656 }
657 
658 static const struct drm_plane_helper_funcs ssd130x_primary_plane_helper_funcs = {
659 	DRM_GEM_SHADOW_PLANE_HELPER_FUNCS,
660 	.atomic_check = drm_plane_helper_atomic_check,
661 	.atomic_update = ssd130x_primary_plane_helper_atomic_update,
662 	.atomic_disable = ssd130x_primary_plane_helper_atomic_disable,
663 };
664 
665 static const struct drm_plane_funcs ssd130x_primary_plane_funcs = {
666 	.update_plane = drm_atomic_helper_update_plane,
667 	.disable_plane = drm_atomic_helper_disable_plane,
668 	.destroy = drm_plane_cleanup,
669 	DRM_GEM_SHADOW_PLANE_FUNCS,
670 };
671 
672 static enum drm_mode_status ssd130x_crtc_helper_mode_valid(struct drm_crtc *crtc,
673 							   const struct drm_display_mode *mode)
674 {
675 	struct ssd130x_device *ssd130x = drm_to_ssd130x(crtc->dev);
676 
677 	if (mode->hdisplay != ssd130x->mode.hdisplay &&
678 	    mode->vdisplay != ssd130x->mode.vdisplay)
679 		return MODE_ONE_SIZE;
680 	else if (mode->hdisplay != ssd130x->mode.hdisplay)
681 		return MODE_ONE_WIDTH;
682 	else if (mode->vdisplay != ssd130x->mode.vdisplay)
683 		return MODE_ONE_HEIGHT;
684 
685 	return MODE_OK;
686 }
687 
688 /*
689  * The CRTC is always enabled. Screen updates are performed by
690  * the primary plane's atomic_update function. Disabling clears
691  * the screen in the primary plane's atomic_disable function.
692  */
693 static const struct drm_crtc_helper_funcs ssd130x_crtc_helper_funcs = {
694 	.mode_valid = ssd130x_crtc_helper_mode_valid,
695 	.atomic_check = drm_crtc_helper_atomic_check,
696 };
697 
698 static const struct drm_crtc_funcs ssd130x_crtc_funcs = {
699 	.reset = drm_atomic_helper_crtc_reset,
700 	.destroy = drm_crtc_cleanup,
701 	.set_config = drm_atomic_helper_set_config,
702 	.page_flip = drm_atomic_helper_page_flip,
703 	.atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
704 	.atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
705 };
706 
707 static void ssd130x_encoder_helper_atomic_enable(struct drm_encoder *encoder,
708 						 struct drm_atomic_state *state)
709 {
710 	struct drm_device *drm = encoder->dev;
711 	struct ssd130x_device *ssd130x = drm_to_ssd130x(drm);
712 	int ret;
713 
714 	ret = ssd130x_power_on(ssd130x);
715 	if (ret)
716 		return;
717 
718 	ret = ssd130x_init(ssd130x);
719 	if (ret)
720 		goto power_off;
721 
722 	ret = ssd130x_buf_alloc(ssd130x);
723 	if (ret)
724 		goto power_off;
725 
726 	ssd130x_write_cmd(ssd130x, 1, SSD130X_DISPLAY_ON);
727 
728 	backlight_enable(ssd130x->bl_dev);
729 
730 	return;
731 
732 power_off:
733 	ssd130x_power_off(ssd130x);
734 	return;
735 }
736 
737 static void ssd130x_encoder_helper_atomic_disable(struct drm_encoder *encoder,
738 						  struct drm_atomic_state *state)
739 {
740 	struct drm_device *drm = encoder->dev;
741 	struct ssd130x_device *ssd130x = drm_to_ssd130x(drm);
742 
743 	backlight_disable(ssd130x->bl_dev);
744 
745 	ssd130x_write_cmd(ssd130x, 1, SSD130X_DISPLAY_OFF);
746 
747 	ssd130x_buf_free(ssd130x);
748 
749 	ssd130x_power_off(ssd130x);
750 }
751 
752 static const struct drm_encoder_helper_funcs ssd130x_encoder_helper_funcs = {
753 	.atomic_enable = ssd130x_encoder_helper_atomic_enable,
754 	.atomic_disable = ssd130x_encoder_helper_atomic_disable,
755 };
756 
757 static const struct drm_encoder_funcs ssd130x_encoder_funcs = {
758 	.destroy = drm_encoder_cleanup,
759 };
760 
761 static int ssd130x_connector_helper_get_modes(struct drm_connector *connector)
762 {
763 	struct ssd130x_device *ssd130x = drm_to_ssd130x(connector->dev);
764 	struct drm_display_mode *mode;
765 	struct device *dev = ssd130x->dev;
766 
767 	mode = drm_mode_duplicate(connector->dev, &ssd130x->mode);
768 	if (!mode) {
769 		dev_err(dev, "Failed to duplicated mode\n");
770 		return 0;
771 	}
772 
773 	drm_mode_probed_add(connector, mode);
774 	drm_set_preferred_mode(connector, mode->hdisplay, mode->vdisplay);
775 
776 	/* There is only a single mode */
777 	return 1;
778 }
779 
780 static const struct drm_connector_helper_funcs ssd130x_connector_helper_funcs = {
781 	.get_modes = ssd130x_connector_helper_get_modes,
782 };
783 
784 static const struct drm_connector_funcs ssd130x_connector_funcs = {
785 	.reset = drm_atomic_helper_connector_reset,
786 	.fill_modes = drm_helper_probe_single_connector_modes,
787 	.destroy = drm_connector_cleanup,
788 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
789 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
790 };
791 
792 static const struct drm_mode_config_funcs ssd130x_mode_config_funcs = {
793 	.fb_create = drm_gem_fb_create_with_dirty,
794 	.atomic_check = drm_atomic_helper_check,
795 	.atomic_commit = drm_atomic_helper_commit,
796 };
797 
798 static const uint32_t ssd130x_formats[] = {
799 	DRM_FORMAT_XRGB8888,
800 };
801 
802 DEFINE_DRM_GEM_FOPS(ssd130x_fops);
803 
804 static const struct drm_driver ssd130x_drm_driver = {
805 	DRM_GEM_SHMEM_DRIVER_OPS,
806 	.name			= DRIVER_NAME,
807 	.desc			= DRIVER_DESC,
808 	.date			= DRIVER_DATE,
809 	.major			= DRIVER_MAJOR,
810 	.minor			= DRIVER_MINOR,
811 	.driver_features	= DRIVER_ATOMIC | DRIVER_GEM | DRIVER_MODESET,
812 	.fops			= &ssd130x_fops,
813 };
814 
815 static int ssd130x_update_bl(struct backlight_device *bdev)
816 {
817 	struct ssd130x_device *ssd130x = bl_get_data(bdev);
818 	int brightness = backlight_get_brightness(bdev);
819 	int ret;
820 
821 	ssd130x->contrast = brightness;
822 
823 	ret = ssd130x_write_cmd(ssd130x, 1, SSD130X_CONTRAST);
824 	if (ret < 0)
825 		return ret;
826 
827 	ret = ssd130x_write_cmd(ssd130x, 1, ssd130x->contrast);
828 	if (ret < 0)
829 		return ret;
830 
831 	return 0;
832 }
833 
834 static const struct backlight_ops ssd130xfb_bl_ops = {
835 	.update_status	= ssd130x_update_bl,
836 };
837 
838 static void ssd130x_parse_properties(struct ssd130x_device *ssd130x)
839 {
840 	struct device *dev = ssd130x->dev;
841 
842 	if (device_property_read_u32(dev, "solomon,width", &ssd130x->width))
843 		ssd130x->width = ssd130x->device_info->default_width;
844 
845 	if (device_property_read_u32(dev, "solomon,height", &ssd130x->height))
846 		ssd130x->height = ssd130x->device_info->default_height;
847 
848 	if (device_property_read_u32(dev, "solomon,page-offset", &ssd130x->page_offset))
849 		ssd130x->page_offset = 1;
850 
851 	if (device_property_read_u32(dev, "solomon,col-offset", &ssd130x->col_offset))
852 		ssd130x->col_offset = 0;
853 
854 	if (device_property_read_u32(dev, "solomon,com-offset", &ssd130x->com_offset))
855 		ssd130x->com_offset = 0;
856 
857 	if (device_property_read_u32(dev, "solomon,prechargep1", &ssd130x->prechargep1))
858 		ssd130x->prechargep1 = 2;
859 
860 	if (device_property_read_u32(dev, "solomon,prechargep2", &ssd130x->prechargep2))
861 		ssd130x->prechargep2 = 2;
862 
863 	if (!device_property_read_u8_array(dev, "solomon,lookup-table",
864 					   ssd130x->lookup_table,
865 					   ARRAY_SIZE(ssd130x->lookup_table)))
866 		ssd130x->lookup_table_set = 1;
867 
868 	ssd130x->seg_remap = !device_property_read_bool(dev, "solomon,segment-no-remap");
869 	ssd130x->com_seq = device_property_read_bool(dev, "solomon,com-seq");
870 	ssd130x->com_lrremap = device_property_read_bool(dev, "solomon,com-lrremap");
871 	ssd130x->com_invdir = device_property_read_bool(dev, "solomon,com-invdir");
872 	ssd130x->area_color_enable =
873 		device_property_read_bool(dev, "solomon,area-color-enable");
874 	ssd130x->low_power = device_property_read_bool(dev, "solomon,low-power");
875 
876 	ssd130x->contrast = 127;
877 	ssd130x->vcomh = ssd130x->device_info->default_vcomh;
878 
879 	/* Setup display timing */
880 	if (device_property_read_u32(dev, "solomon,dclk-div", &ssd130x->dclk_div))
881 		ssd130x->dclk_div = ssd130x->device_info->default_dclk_div;
882 	if (device_property_read_u32(dev, "solomon,dclk-frq", &ssd130x->dclk_frq))
883 		ssd130x->dclk_frq = ssd130x->device_info->default_dclk_frq;
884 }
885 
886 static int ssd130x_init_modeset(struct ssd130x_device *ssd130x)
887 {
888 	struct drm_display_mode *mode = &ssd130x->mode;
889 	struct device *dev = ssd130x->dev;
890 	struct drm_device *drm = &ssd130x->drm;
891 	unsigned long max_width, max_height;
892 	struct drm_plane *primary_plane;
893 	struct drm_crtc *crtc;
894 	struct drm_encoder *encoder;
895 	struct drm_connector *connector;
896 	int ret;
897 
898 	/*
899 	 * Modesetting
900 	 */
901 
902 	ret = drmm_mode_config_init(drm);
903 	if (ret) {
904 		dev_err(dev, "DRM mode config init failed: %d\n", ret);
905 		return ret;
906 	}
907 
908 	mode->type = DRM_MODE_TYPE_DRIVER;
909 	mode->clock = 1;
910 	mode->hdisplay = mode->htotal = ssd130x->width;
911 	mode->hsync_start = mode->hsync_end = ssd130x->width;
912 	mode->vdisplay = mode->vtotal = ssd130x->height;
913 	mode->vsync_start = mode->vsync_end = ssd130x->height;
914 	mode->width_mm = 27;
915 	mode->height_mm = 27;
916 
917 	max_width = max_t(unsigned long, mode->hdisplay, DRM_SHADOW_PLANE_MAX_WIDTH);
918 	max_height = max_t(unsigned long, mode->vdisplay, DRM_SHADOW_PLANE_MAX_HEIGHT);
919 
920 	drm->mode_config.min_width = mode->hdisplay;
921 	drm->mode_config.max_width = max_width;
922 	drm->mode_config.min_height = mode->vdisplay;
923 	drm->mode_config.max_height = max_height;
924 	drm->mode_config.preferred_depth = 24;
925 	drm->mode_config.funcs = &ssd130x_mode_config_funcs;
926 
927 	/* Primary plane */
928 
929 	primary_plane = &ssd130x->primary_plane;
930 	ret = drm_universal_plane_init(drm, primary_plane, 0, &ssd130x_primary_plane_funcs,
931 				       ssd130x_formats, ARRAY_SIZE(ssd130x_formats),
932 				       NULL, DRM_PLANE_TYPE_PRIMARY, NULL);
933 	if (ret) {
934 		dev_err(dev, "DRM primary plane init failed: %d\n", ret);
935 		return ret;
936 	}
937 
938 	drm_plane_helper_add(primary_plane, &ssd130x_primary_plane_helper_funcs);
939 
940 	drm_plane_enable_fb_damage_clips(primary_plane);
941 
942 	/* CRTC */
943 
944 	crtc = &ssd130x->crtc;
945 	ret = drm_crtc_init_with_planes(drm, crtc, primary_plane, NULL,
946 					&ssd130x_crtc_funcs, NULL);
947 	if (ret) {
948 		dev_err(dev, "DRM crtc init failed: %d\n", ret);
949 		return ret;
950 	}
951 
952 	drm_crtc_helper_add(crtc, &ssd130x_crtc_helper_funcs);
953 
954 	/* Encoder */
955 
956 	encoder = &ssd130x->encoder;
957 	ret = drm_encoder_init(drm, encoder, &ssd130x_encoder_funcs,
958 			       DRM_MODE_ENCODER_NONE, NULL);
959 	if (ret) {
960 		dev_err(dev, "DRM encoder init failed: %d\n", ret);
961 		return ret;
962 	}
963 
964 	drm_encoder_helper_add(encoder, &ssd130x_encoder_helper_funcs);
965 
966 	encoder->possible_crtcs = drm_crtc_mask(crtc);
967 
968 	/* Connector */
969 
970 	connector = &ssd130x->connector;
971 	ret = drm_connector_init(drm, connector, &ssd130x_connector_funcs,
972 				 DRM_MODE_CONNECTOR_Unknown);
973 	if (ret) {
974 		dev_err(dev, "DRM connector init failed: %d\n", ret);
975 		return ret;
976 	}
977 
978 	drm_connector_helper_add(connector, &ssd130x_connector_helper_funcs);
979 
980 	ret = drm_connector_attach_encoder(connector, encoder);
981 	if (ret) {
982 		dev_err(dev, "DRM attach connector to encoder failed: %d\n", ret);
983 		return ret;
984 	}
985 
986 	drm_mode_config_reset(drm);
987 
988 	return 0;
989 }
990 
991 static int ssd130x_get_resources(struct ssd130x_device *ssd130x)
992 {
993 	struct device *dev = ssd130x->dev;
994 
995 	ssd130x->reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
996 	if (IS_ERR(ssd130x->reset))
997 		return dev_err_probe(dev, PTR_ERR(ssd130x->reset),
998 				     "Failed to get reset gpio\n");
999 
1000 	ssd130x->vcc_reg = devm_regulator_get(dev, "vcc");
1001 	if (IS_ERR(ssd130x->vcc_reg))
1002 		return dev_err_probe(dev, PTR_ERR(ssd130x->vcc_reg),
1003 				     "Failed to get VCC regulator\n");
1004 
1005 	return 0;
1006 }
1007 
1008 struct ssd130x_device *ssd130x_probe(struct device *dev, struct regmap *regmap)
1009 {
1010 	struct ssd130x_device *ssd130x;
1011 	struct backlight_device *bl;
1012 	struct drm_device *drm;
1013 	int ret;
1014 
1015 	ssd130x = devm_drm_dev_alloc(dev, &ssd130x_drm_driver,
1016 				     struct ssd130x_device, drm);
1017 	if (IS_ERR(ssd130x))
1018 		return ERR_PTR(dev_err_probe(dev, PTR_ERR(ssd130x),
1019 					     "Failed to allocate DRM device\n"));
1020 
1021 	drm = &ssd130x->drm;
1022 
1023 	ssd130x->dev = dev;
1024 	ssd130x->regmap = regmap;
1025 	ssd130x->device_info = device_get_match_data(dev);
1026 
1027 	if (ssd130x->device_info->page_mode_only)
1028 		ssd130x->page_address_mode = 1;
1029 
1030 	ssd130x_parse_properties(ssd130x);
1031 
1032 	ret = ssd130x_get_resources(ssd130x);
1033 	if (ret)
1034 		return ERR_PTR(ret);
1035 
1036 	bl = devm_backlight_device_register(dev, dev_name(dev), dev, ssd130x,
1037 					    &ssd130xfb_bl_ops, NULL);
1038 	if (IS_ERR(bl))
1039 		return ERR_PTR(dev_err_probe(dev, PTR_ERR(bl),
1040 					     "Unable to register backlight device\n"));
1041 
1042 	bl->props.brightness = ssd130x->contrast;
1043 	bl->props.max_brightness = MAX_CONTRAST;
1044 	ssd130x->bl_dev = bl;
1045 
1046 	ret = ssd130x_init_modeset(ssd130x);
1047 	if (ret)
1048 		return ERR_PTR(ret);
1049 
1050 	ret = drm_dev_register(drm, 0);
1051 	if (ret)
1052 		return ERR_PTR(dev_err_probe(dev, ret, "DRM device register failed\n"));
1053 
1054 	drm_fbdev_generic_setup(drm, 32);
1055 
1056 	return ssd130x;
1057 }
1058 EXPORT_SYMBOL_GPL(ssd130x_probe);
1059 
1060 void ssd130x_remove(struct ssd130x_device *ssd130x)
1061 {
1062 	drm_dev_unplug(&ssd130x->drm);
1063 }
1064 EXPORT_SYMBOL_GPL(ssd130x_remove);
1065 
1066 void ssd130x_shutdown(struct ssd130x_device *ssd130x)
1067 {
1068 	drm_atomic_helper_shutdown(&ssd130x->drm);
1069 }
1070 EXPORT_SYMBOL_GPL(ssd130x_shutdown);
1071 
1072 MODULE_DESCRIPTION(DRIVER_DESC);
1073 MODULE_AUTHOR("Javier Martinez Canillas <javierm@redhat.com>");
1074 MODULE_LICENSE("GPL v2");
1075