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
97const 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};
142EXPORT_SYMBOL_NS_GPL(ssd130x_variants, DRM_SSD130X);
143
144struct ssd130x_plane_state {
145	struct drm_shadow_plane_state base;
146	/* Intermediate buffer to convert pixels from XRGB8888 to HW format */
147	u8 *buffer;
148	/* Buffer to store pixels in HW format and written to the panel */
149	u8 *data_array;
150};
151
152static inline struct ssd130x_plane_state *to_ssd130x_plane_state(struct drm_plane_state *state)
153{
154	return container_of(state, struct ssd130x_plane_state, base.base);
155}
156
157static inline struct ssd130x_device *drm_to_ssd130x(struct drm_device *drm)
158{
159	return container_of(drm, struct ssd130x_device, drm);
160}
161
162/*
163 * Helper to write data (SSD130X_DATA) to the device.
164 */
165static int ssd130x_write_data(struct ssd130x_device *ssd130x, u8 *values, int count)
166{
167	return regmap_bulk_write(ssd130x->regmap, SSD130X_DATA, values, count);
168}
169
170/*
171 * Helper to write command (SSD130X_COMMAND). The fist variadic argument
172 * is the command to write and the following are the command options.
173 *
174 * Note that the ssd130x protocol requires each command and option to be
175 * written as a SSD130X_COMMAND device register value. That is why a call
176 * to regmap_write(..., SSD130X_COMMAND, ...) is done for each argument.
177 */
178static int ssd130x_write_cmd(struct ssd130x_device *ssd130x, int count,
179			     /* u8 cmd, u8 option, ... */...)
180{
181	va_list ap;
182	u8 value;
183	int ret;
184
185	va_start(ap, count);
186
187	do {
188		value = va_arg(ap, int);
189		ret = regmap_write(ssd130x->regmap, SSD130X_COMMAND, value);
190		if (ret)
191			goto out_end;
192	} while (--count);
193
194out_end:
195	va_end(ap);
196
197	return ret;
198}
199
200/* Set address range for horizontal/vertical addressing modes */
201static int ssd130x_set_col_range(struct ssd130x_device *ssd130x,
202				 u8 col_start, u8 cols)
203{
204	u8 col_end = col_start + cols - 1;
205	int ret;
206
207	if (col_start == ssd130x->col_start && col_end == ssd130x->col_end)
208		return 0;
209
210	ret = ssd130x_write_cmd(ssd130x, 3, SSD130X_SET_COL_RANGE, col_start, col_end);
211	if (ret < 0)
212		return ret;
213
214	ssd130x->col_start = col_start;
215	ssd130x->col_end = col_end;
216	return 0;
217}
218
219static int ssd130x_set_page_range(struct ssd130x_device *ssd130x,
220				  u8 page_start, u8 pages)
221{
222	u8 page_end = page_start + pages - 1;
223	int ret;
224
225	if (page_start == ssd130x->page_start && page_end == ssd130x->page_end)
226		return 0;
227
228	ret = ssd130x_write_cmd(ssd130x, 3, SSD130X_SET_PAGE_RANGE, page_start, page_end);
229	if (ret < 0)
230		return ret;
231
232	ssd130x->page_start = page_start;
233	ssd130x->page_end = page_end;
234	return 0;
235}
236
237/* Set page and column start address for page addressing mode */
238static int ssd130x_set_page_pos(struct ssd130x_device *ssd130x,
239				u8 page_start, u8 col_start)
240{
241	int ret;
242	u32 page, col_low, col_high;
243
244	page = SSD130X_START_PAGE_ADDRESS |
245	       SSD130X_START_PAGE_ADDRESS_SET(page_start);
246	col_low = SSD130X_PAGE_COL_START_LOW |
247		  SSD130X_PAGE_COL_START_LOW_SET(col_start);
248	col_high = SSD130X_PAGE_COL_START_HIGH |
249		   SSD130X_PAGE_COL_START_HIGH_SET(col_start);
250	ret = ssd130x_write_cmd(ssd130x, 3, page, col_low, col_high);
251	if (ret < 0)
252		return ret;
253
254	return 0;
255}
256
257static int ssd130x_pwm_enable(struct ssd130x_device *ssd130x)
258{
259	struct device *dev = ssd130x->dev;
260	struct pwm_state pwmstate;
261
262	ssd130x->pwm = pwm_get(dev, NULL);
263	if (IS_ERR(ssd130x->pwm)) {
264		dev_err(dev, "Could not get PWM from firmware description!\n");
265		return PTR_ERR(ssd130x->pwm);
266	}
267
268	pwm_init_state(ssd130x->pwm, &pwmstate);
269	pwm_set_relative_duty_cycle(&pwmstate, 50, 100);
270	pwm_apply_state(ssd130x->pwm, &pwmstate);
271
272	/* Enable the PWM */
273	pwm_enable(ssd130x->pwm);
274
275	dev_dbg(dev, "Using PWM%d with a %lluns period.\n",
276		ssd130x->pwm->pwm, pwm_get_period(ssd130x->pwm));
277
278	return 0;
279}
280
281static void ssd130x_reset(struct ssd130x_device *ssd130x)
282{
283	if (!ssd130x->reset)
284		return;
285
286	/* Reset the screen */
287	gpiod_set_value_cansleep(ssd130x->reset, 1);
288	udelay(4);
289	gpiod_set_value_cansleep(ssd130x->reset, 0);
290	udelay(4);
291}
292
293static int ssd130x_power_on(struct ssd130x_device *ssd130x)
294{
295	struct device *dev = ssd130x->dev;
296	int ret;
297
298	ssd130x_reset(ssd130x);
299
300	ret = regulator_enable(ssd130x->vcc_reg);
301	if (ret) {
302		dev_err(dev, "Failed to enable VCC: %d\n", ret);
303		return ret;
304	}
305
306	if (ssd130x->device_info->need_pwm) {
307		ret = ssd130x_pwm_enable(ssd130x);
308		if (ret) {
309			dev_err(dev, "Failed to enable PWM: %d\n", ret);
310			regulator_disable(ssd130x->vcc_reg);
311			return ret;
312		}
313	}
314
315	return 0;
316}
317
318static void ssd130x_power_off(struct ssd130x_device *ssd130x)
319{
320	pwm_disable(ssd130x->pwm);
321	pwm_put(ssd130x->pwm);
322
323	regulator_disable(ssd130x->vcc_reg);
324}
325
326static int ssd130x_init(struct ssd130x_device *ssd130x)
327{
328	u32 precharge, dclk, com_invdir, compins, chargepump, seg_remap;
329	bool scan_mode;
330	int ret;
331
332	/* Set initial contrast */
333	ret = ssd130x_write_cmd(ssd130x, 2, SSD130X_CONTRAST, ssd130x->contrast);
334	if (ret < 0)
335		return ret;
336
337	/* Set segment re-map */
338	seg_remap = (SSD130X_SET_SEG_REMAP |
339		     SSD130X_SET_SEG_REMAP_SET(ssd130x->seg_remap));
340	ret = ssd130x_write_cmd(ssd130x, 1, seg_remap);
341	if (ret < 0)
342		return ret;
343
344	/* Set COM direction */
345	com_invdir = (SSD130X_SET_COM_SCAN_DIR |
346		      SSD130X_SET_COM_SCAN_DIR_SET(ssd130x->com_invdir));
347	ret = ssd130x_write_cmd(ssd130x,  1, com_invdir);
348	if (ret < 0)
349		return ret;
350
351	/* Set multiplex ratio value */
352	ret = ssd130x_write_cmd(ssd130x, 2, SSD130X_SET_MULTIPLEX_RATIO, ssd130x->height - 1);
353	if (ret < 0)
354		return ret;
355
356	/* set display offset value */
357	ret = ssd130x_write_cmd(ssd130x, 2, SSD130X_SET_DISPLAY_OFFSET, ssd130x->com_offset);
358	if (ret < 0)
359		return ret;
360
361	/* Set clock frequency */
362	dclk = (SSD130X_SET_CLOCK_DIV_SET(ssd130x->dclk_div - 1) |
363		SSD130X_SET_CLOCK_FREQ_SET(ssd130x->dclk_frq));
364	ret = ssd130x_write_cmd(ssd130x, 2, SSD130X_SET_CLOCK_FREQ, dclk);
365	if (ret < 0)
366		return ret;
367
368	/* Set Area Color Mode ON/OFF & Low Power Display Mode */
369	if (ssd130x->area_color_enable || ssd130x->low_power) {
370		u32 mode = 0;
371
372		if (ssd130x->area_color_enable)
373			mode |= SSD130X_SET_AREA_COLOR_MODE_ENABLE;
374
375		if (ssd130x->low_power)
376			mode |= SSD130X_SET_AREA_COLOR_MODE_LOW_POWER;
377
378		ret = ssd130x_write_cmd(ssd130x, 2, SSD130X_SET_AREA_COLOR_MODE, mode);
379		if (ret < 0)
380			return ret;
381	}
382
383	/* Set precharge period in number of ticks from the internal clock */
384	precharge = (SSD130X_SET_PRECHARGE_PERIOD1_SET(ssd130x->prechargep1) |
385		     SSD130X_SET_PRECHARGE_PERIOD2_SET(ssd130x->prechargep2));
386	ret = ssd130x_write_cmd(ssd130x, 2, SSD130X_SET_PRECHARGE_PERIOD, precharge);
387	if (ret < 0)
388		return ret;
389
390	/* Set COM pins configuration */
391	compins = BIT(1);
392	/*
393	 * The COM scan mode field values are the inverse of the boolean DT
394	 * property "solomon,com-seq". The value 0b means scan from COM0 to
395	 * COM[N - 1] while 1b means scan from COM[N - 1] to COM0.
396	 */
397	scan_mode = !ssd130x->com_seq;
398	compins |= (SSD130X_SET_COM_PINS_CONFIG1_SET(scan_mode) |
399		    SSD130X_SET_COM_PINS_CONFIG2_SET(ssd130x->com_lrremap));
400	ret = ssd130x_write_cmd(ssd130x, 2, SSD130X_SET_COM_PINS_CONFIG, compins);
401	if (ret < 0)
402		return ret;
403
404	/* Set VCOMH */
405	ret = ssd130x_write_cmd(ssd130x, 2, SSD130X_SET_VCOMH, ssd130x->vcomh);
406	if (ret < 0)
407		return ret;
408
409	/* Turn on the DC-DC Charge Pump */
410	chargepump = BIT(4);
411
412	if (ssd130x->device_info->need_chargepump)
413		chargepump |= BIT(2);
414
415	ret = ssd130x_write_cmd(ssd130x, 2, SSD130X_CHARGE_PUMP, chargepump);
416	if (ret < 0)
417		return ret;
418
419	/* Set lookup table */
420	if (ssd130x->lookup_table_set) {
421		int i;
422
423		ret = ssd130x_write_cmd(ssd130x, 1, SSD130X_SET_LOOKUP_TABLE);
424		if (ret < 0)
425			return ret;
426
427		for (i = 0; i < ARRAY_SIZE(ssd130x->lookup_table); i++) {
428			u8 val = ssd130x->lookup_table[i];
429
430			if (val < 31 || val > 63)
431				dev_warn(ssd130x->dev,
432					 "lookup table index %d value out of range 31 <= %d <= 63\n",
433					 i, val);
434			ret = ssd130x_write_cmd(ssd130x, 1, val);
435			if (ret < 0)
436				return ret;
437		}
438	}
439
440	/* Switch to page addressing mode */
441	if (ssd130x->page_address_mode)
442		return ssd130x_write_cmd(ssd130x, 2, SSD130X_SET_ADDRESS_MODE,
443					 SSD130X_SET_ADDRESS_MODE_PAGE);
444
445	/* Switch to horizontal addressing mode */
446	return ssd130x_write_cmd(ssd130x, 2, SSD130X_SET_ADDRESS_MODE,
447				 SSD130X_SET_ADDRESS_MODE_HORIZONTAL);
448}
449
450static int ssd130x_update_rect(struct ssd130x_device *ssd130x,
451			       struct ssd130x_plane_state *ssd130x_state,
452			       struct drm_rect *rect)
453{
454	unsigned int x = rect->x1;
455	unsigned int y = rect->y1;
456	u8 *buf = ssd130x_state->buffer;
457	u8 *data_array = ssd130x_state->data_array;
458	unsigned int width = drm_rect_width(rect);
459	unsigned int height = drm_rect_height(rect);
460	unsigned int line_length = DIV_ROUND_UP(width, 8);
461	unsigned int page_height = ssd130x->device_info->page_height;
462	unsigned int pages = DIV_ROUND_UP(height, page_height);
463	struct drm_device *drm = &ssd130x->drm;
464	u32 array_idx = 0;
465	int ret, i, j, k;
466
467	drm_WARN_ONCE(drm, y % 8 != 0, "y must be aligned to screen page\n");
468
469	/*
470	 * The screen is divided in pages, each having a height of 8
471	 * pixels, and the width of the screen. When sending a byte of
472	 * data to the controller, it gives the 8 bits for the current
473	 * column. I.e, the first byte are the 8 bits of the first
474	 * column, then the 8 bits for the second column, etc.
475	 *
476	 *
477	 * Representation of the screen, assuming it is 5 bits
478	 * wide. Each letter-number combination is a bit that controls
479	 * one pixel.
480	 *
481	 * A0 A1 A2 A3 A4
482	 * B0 B1 B2 B3 B4
483	 * C0 C1 C2 C3 C4
484	 * D0 D1 D2 D3 D4
485	 * E0 E1 E2 E3 E4
486	 * F0 F1 F2 F3 F4
487	 * G0 G1 G2 G3 G4
488	 * H0 H1 H2 H3 H4
489	 *
490	 * If you want to update this screen, you need to send 5 bytes:
491	 *  (1) A0 B0 C0 D0 E0 F0 G0 H0
492	 *  (2) A1 B1 C1 D1 E1 F1 G1 H1
493	 *  (3) A2 B2 C2 D2 E2 F2 G2 H2
494	 *  (4) A3 B3 C3 D3 E3 F3 G3 H3
495	 *  (5) A4 B4 C4 D4 E4 F4 G4 H4
496	 */
497
498	if (!ssd130x->page_address_mode) {
499		/* Set address range for horizontal addressing mode */
500		ret = ssd130x_set_col_range(ssd130x, ssd130x->col_offset + x, width);
501		if (ret < 0)
502			return ret;
503
504		ret = ssd130x_set_page_range(ssd130x, ssd130x->page_offset + y / 8, pages);
505		if (ret < 0)
506			return ret;
507	}
508
509	for (i = 0; i < pages; i++) {
510		int m = 8;
511
512		/* Last page may be partial */
513		if (8 * (y / 8 + i + 1) > ssd130x->height)
514			m = ssd130x->height % 8;
515		for (j = 0; j < width; j++) {
516			u8 data = 0;
517
518			for (k = 0; k < m; k++) {
519				u8 byte = buf[(8 * i + k) * line_length + j / 8];
520				u8 bit = (byte >> (j % 8)) & 1;
521
522				data |= bit << k;
523			}
524			data_array[array_idx++] = data;
525		}
526
527		/*
528		 * In page addressing mode, the start address needs to be reset,
529		 * and each page then needs to be written out separately.
530		 */
531		if (ssd130x->page_address_mode) {
532			ret = ssd130x_set_page_pos(ssd130x,
533						   ssd130x->page_offset + i,
534						   ssd130x->col_offset + x);
535			if (ret < 0)
536				return ret;
537
538			ret = ssd130x_write_data(ssd130x, data_array, width);
539			if (ret < 0)
540				return ret;
541
542			array_idx = 0;
543		}
544	}
545
546	/* Write out update in one go if we aren't using page addressing mode */
547	if (!ssd130x->page_address_mode)
548		ret = ssd130x_write_data(ssd130x, data_array, width * pages);
549
550	return ret;
551}
552
553static void ssd130x_clear_screen(struct ssd130x_device *ssd130x,
554				 struct ssd130x_plane_state *ssd130x_state)
555{
556	unsigned int page_height = ssd130x->device_info->page_height;
557	unsigned int pages = DIV_ROUND_UP(ssd130x->height, page_height);
558	u8 *data_array = ssd130x_state->data_array;
559	unsigned int width = ssd130x->width;
560	int ret, i;
561
562	if (!ssd130x->page_address_mode) {
563		memset(data_array, 0, width * pages);
564
565		/* Set address range for horizontal addressing mode */
566		ret = ssd130x_set_col_range(ssd130x, ssd130x->col_offset, width);
567		if (ret < 0)
568			return;
569
570		ret = ssd130x_set_page_range(ssd130x, ssd130x->page_offset, pages);
571		if (ret < 0)
572			return;
573
574		/* Write out update in one go if we aren't using page addressing mode */
575		ssd130x_write_data(ssd130x, data_array, width * pages);
576	} else {
577		/*
578		 * In page addressing mode, the start address needs to be reset,
579		 * and each page then needs to be written out separately.
580		 */
581		memset(data_array, 0, width);
582
583		for (i = 0; i < pages; i++) {
584			ret = ssd130x_set_page_pos(ssd130x,
585						   ssd130x->page_offset + i,
586						   ssd130x->col_offset);
587			if (ret < 0)
588				return;
589
590			ret = ssd130x_write_data(ssd130x, data_array, width);
591			if (ret < 0)
592				return;
593		}
594	}
595}
596
597static int ssd130x_fb_blit_rect(struct drm_plane_state *state,
598				const struct iosys_map *vmap,
599				struct drm_rect *rect)
600{
601	struct drm_framebuffer *fb = state->fb;
602	struct ssd130x_device *ssd130x = drm_to_ssd130x(fb->dev);
603	unsigned int page_height = ssd130x->device_info->page_height;
604	struct ssd130x_plane_state *ssd130x_state = to_ssd130x_plane_state(state);
605	u8 *buf = ssd130x_state->buffer;
606	struct iosys_map dst;
607	unsigned int dst_pitch;
608	int ret = 0;
609
610	/* Align y to display page boundaries */
611	rect->y1 = round_down(rect->y1, page_height);
612	rect->y2 = min_t(unsigned int, round_up(rect->y2, page_height), ssd130x->height);
613
614	dst_pitch = DIV_ROUND_UP(drm_rect_width(rect), 8);
615
616	ret = drm_gem_fb_begin_cpu_access(fb, DMA_FROM_DEVICE);
617	if (ret)
618		return ret;
619
620	iosys_map_set_vaddr(&dst, buf);
621	drm_fb_xrgb8888_to_mono(&dst, &dst_pitch, vmap, fb, rect);
622
623	drm_gem_fb_end_cpu_access(fb, DMA_FROM_DEVICE);
624
625	ssd130x_update_rect(ssd130x, ssd130x_state, rect);
626
627	return ret;
628}
629
630static int ssd130x_primary_plane_helper_atomic_check(struct drm_plane *plane,
631						     struct drm_atomic_state *state)
632{
633	struct drm_device *drm = plane->dev;
634	struct ssd130x_device *ssd130x = drm_to_ssd130x(drm);
635	struct drm_plane_state *plane_state = drm_atomic_get_new_plane_state(state, plane);
636	struct ssd130x_plane_state *ssd130x_state = to_ssd130x_plane_state(plane_state);
637	unsigned int page_height = ssd130x->device_info->page_height;
638	unsigned int pages = DIV_ROUND_UP(ssd130x->height, page_height);
639	const struct drm_format_info *fi;
640	unsigned int pitch;
641	int ret;
642
643	ret = drm_plane_helper_atomic_check(plane, state);
644	if (ret)
645		return ret;
646
647	fi = drm_format_info(DRM_FORMAT_R1);
648	if (!fi)
649		return -EINVAL;
650
651	pitch = drm_format_info_min_pitch(fi, 0, ssd130x->width);
652
653	ssd130x_state->buffer = kcalloc(pitch, ssd130x->height, GFP_KERNEL);
654	if (!ssd130x_state->buffer)
655		return -ENOMEM;
656
657	ssd130x_state->data_array = kcalloc(ssd130x->width, pages, GFP_KERNEL);
658	if (!ssd130x_state->data_array) {
659		kfree(ssd130x_state->buffer);
660		/* Set to prevent a double free in .atomic_destroy_state() */
661		ssd130x_state->buffer = NULL;
662		return -ENOMEM;
663	}
664
665	return 0;
666}
667
668static void ssd130x_primary_plane_helper_atomic_update(struct drm_plane *plane,
669						       struct drm_atomic_state *state)
670{
671	struct drm_plane_state *plane_state = drm_atomic_get_new_plane_state(state, plane);
672	struct drm_plane_state *old_plane_state = drm_atomic_get_old_plane_state(state, plane);
673	struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(plane_state);
674	struct drm_atomic_helper_damage_iter iter;
675	struct drm_device *drm = plane->dev;
676	struct drm_rect dst_clip;
677	struct drm_rect damage;
678	int idx;
679
680	if (!drm_dev_enter(drm, &idx))
681		return;
682
683	drm_atomic_helper_damage_iter_init(&iter, old_plane_state, plane_state);
684	drm_atomic_for_each_plane_damage(&iter, &damage) {
685		dst_clip = plane_state->dst;
686
687		if (!drm_rect_intersect(&dst_clip, &damage))
688			continue;
689
690		ssd130x_fb_blit_rect(plane_state, &shadow_plane_state->data[0], &dst_clip);
691	}
692
693	drm_dev_exit(idx);
694}
695
696static void ssd130x_primary_plane_helper_atomic_disable(struct drm_plane *plane,
697							struct drm_atomic_state *state)
698{
699	struct drm_device *drm = plane->dev;
700	struct ssd130x_device *ssd130x = drm_to_ssd130x(drm);
701	struct ssd130x_plane_state *ssd130x_state = to_ssd130x_plane_state(plane->state);
702	int idx;
703
704	if (!drm_dev_enter(drm, &idx))
705		return;
706
707	ssd130x_clear_screen(ssd130x, ssd130x_state);
708
709	drm_dev_exit(idx);
710}
711
712/* Called during init to allocate the plane's atomic state. */
713static void ssd130x_primary_plane_reset(struct drm_plane *plane)
714{
715	struct ssd130x_plane_state *ssd130x_state;
716
717	WARN_ON(plane->state);
718
719	ssd130x_state = kzalloc(sizeof(*ssd130x_state), GFP_KERNEL);
720	if (!ssd130x_state)
721		return;
722
723	__drm_gem_reset_shadow_plane(plane, &ssd130x_state->base);
724}
725
726static struct drm_plane_state *ssd130x_primary_plane_duplicate_state(struct drm_plane *plane)
727{
728	struct drm_shadow_plane_state *new_shadow_plane_state;
729	struct ssd130x_plane_state *old_ssd130x_state;
730	struct ssd130x_plane_state *ssd130x_state;
731
732	if (WARN_ON(!plane->state))
733		return NULL;
734
735	old_ssd130x_state = to_ssd130x_plane_state(plane->state);
736	ssd130x_state = kmemdup(old_ssd130x_state, sizeof(*ssd130x_state), GFP_KERNEL);
737	if (!ssd130x_state)
738		return NULL;
739
740	/* The buffers are not duplicated and are allocated in .atomic_check */
741	ssd130x_state->buffer = NULL;
742	ssd130x_state->data_array = NULL;
743
744	new_shadow_plane_state = &ssd130x_state->base;
745
746	__drm_gem_duplicate_shadow_plane_state(plane, new_shadow_plane_state);
747
748	return &new_shadow_plane_state->base;
749}
750
751static void ssd130x_primary_plane_destroy_state(struct drm_plane *plane,
752						struct drm_plane_state *state)
753{
754	struct ssd130x_plane_state *ssd130x_state = to_ssd130x_plane_state(state);
755
756	kfree(ssd130x_state->data_array);
757	kfree(ssd130x_state->buffer);
758
759	__drm_gem_destroy_shadow_plane_state(&ssd130x_state->base);
760
761	kfree(ssd130x_state);
762}
763
764static const struct drm_plane_helper_funcs ssd130x_primary_plane_helper_funcs = {
765	DRM_GEM_SHADOW_PLANE_HELPER_FUNCS,
766	.atomic_check = ssd130x_primary_plane_helper_atomic_check,
767	.atomic_update = ssd130x_primary_plane_helper_atomic_update,
768	.atomic_disable = ssd130x_primary_plane_helper_atomic_disable,
769};
770
771static const struct drm_plane_funcs ssd130x_primary_plane_funcs = {
772	.update_plane = drm_atomic_helper_update_plane,
773	.disable_plane = drm_atomic_helper_disable_plane,
774	.reset = ssd130x_primary_plane_reset,
775	.atomic_duplicate_state = ssd130x_primary_plane_duplicate_state,
776	.atomic_destroy_state = ssd130x_primary_plane_destroy_state,
777	.destroy = drm_plane_cleanup,
778};
779
780static enum drm_mode_status ssd130x_crtc_helper_mode_valid(struct drm_crtc *crtc,
781							   const struct drm_display_mode *mode)
782{
783	struct ssd130x_device *ssd130x = drm_to_ssd130x(crtc->dev);
784
785	if (mode->hdisplay != ssd130x->mode.hdisplay &&
786	    mode->vdisplay != ssd130x->mode.vdisplay)
787		return MODE_ONE_SIZE;
788	else if (mode->hdisplay != ssd130x->mode.hdisplay)
789		return MODE_ONE_WIDTH;
790	else if (mode->vdisplay != ssd130x->mode.vdisplay)
791		return MODE_ONE_HEIGHT;
792
793	return MODE_OK;
794}
795
796/*
797 * The CRTC is always enabled. Screen updates are performed by
798 * the primary plane's atomic_update function. Disabling clears
799 * the screen in the primary plane's atomic_disable function.
800 */
801static const struct drm_crtc_helper_funcs ssd130x_crtc_helper_funcs = {
802	.mode_valid = ssd130x_crtc_helper_mode_valid,
803	.atomic_check = drm_crtc_helper_atomic_check,
804};
805
806static const struct drm_crtc_funcs ssd130x_crtc_funcs = {
807	.reset = drm_atomic_helper_crtc_reset,
808	.destroy = drm_crtc_cleanup,
809	.set_config = drm_atomic_helper_set_config,
810	.page_flip = drm_atomic_helper_page_flip,
811	.atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
812	.atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
813};
814
815static void ssd130x_encoder_helper_atomic_enable(struct drm_encoder *encoder,
816						 struct drm_atomic_state *state)
817{
818	struct drm_device *drm = encoder->dev;
819	struct ssd130x_device *ssd130x = drm_to_ssd130x(drm);
820	int ret;
821
822	ret = ssd130x_power_on(ssd130x);
823	if (ret)
824		return;
825
826	ret = ssd130x_init(ssd130x);
827	if (ret)
828		goto power_off;
829
830	ssd130x_write_cmd(ssd130x, 1, SSD130X_DISPLAY_ON);
831
832	backlight_enable(ssd130x->bl_dev);
833
834	return;
835
836power_off:
837	ssd130x_power_off(ssd130x);
838	return;
839}
840
841static void ssd130x_encoder_helper_atomic_disable(struct drm_encoder *encoder,
842						  struct drm_atomic_state *state)
843{
844	struct drm_device *drm = encoder->dev;
845	struct ssd130x_device *ssd130x = drm_to_ssd130x(drm);
846
847	backlight_disable(ssd130x->bl_dev);
848
849	ssd130x_write_cmd(ssd130x, 1, SSD130X_DISPLAY_OFF);
850
851	ssd130x_power_off(ssd130x);
852}
853
854static const struct drm_encoder_helper_funcs ssd130x_encoder_helper_funcs = {
855	.atomic_enable = ssd130x_encoder_helper_atomic_enable,
856	.atomic_disable = ssd130x_encoder_helper_atomic_disable,
857};
858
859static const struct drm_encoder_funcs ssd130x_encoder_funcs = {
860	.destroy = drm_encoder_cleanup,
861};
862
863static int ssd130x_connector_helper_get_modes(struct drm_connector *connector)
864{
865	struct ssd130x_device *ssd130x = drm_to_ssd130x(connector->dev);
866	struct drm_display_mode *mode;
867	struct device *dev = ssd130x->dev;
868
869	mode = drm_mode_duplicate(connector->dev, &ssd130x->mode);
870	if (!mode) {
871		dev_err(dev, "Failed to duplicated mode\n");
872		return 0;
873	}
874
875	drm_mode_probed_add(connector, mode);
876	drm_set_preferred_mode(connector, mode->hdisplay, mode->vdisplay);
877
878	/* There is only a single mode */
879	return 1;
880}
881
882static const struct drm_connector_helper_funcs ssd130x_connector_helper_funcs = {
883	.get_modes = ssd130x_connector_helper_get_modes,
884};
885
886static const struct drm_connector_funcs ssd130x_connector_funcs = {
887	.reset = drm_atomic_helper_connector_reset,
888	.fill_modes = drm_helper_probe_single_connector_modes,
889	.destroy = drm_connector_cleanup,
890	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
891	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
892};
893
894static const struct drm_mode_config_funcs ssd130x_mode_config_funcs = {
895	.fb_create = drm_gem_fb_create_with_dirty,
896	.atomic_check = drm_atomic_helper_check,
897	.atomic_commit = drm_atomic_helper_commit,
898};
899
900static const uint32_t ssd130x_formats[] = {
901	DRM_FORMAT_XRGB8888,
902};
903
904DEFINE_DRM_GEM_FOPS(ssd130x_fops);
905
906static const struct drm_driver ssd130x_drm_driver = {
907	DRM_GEM_SHMEM_DRIVER_OPS,
908	.name			= DRIVER_NAME,
909	.desc			= DRIVER_DESC,
910	.date			= DRIVER_DATE,
911	.major			= DRIVER_MAJOR,
912	.minor			= DRIVER_MINOR,
913	.driver_features	= DRIVER_ATOMIC | DRIVER_GEM | DRIVER_MODESET,
914	.fops			= &ssd130x_fops,
915};
916
917static int ssd130x_update_bl(struct backlight_device *bdev)
918{
919	struct ssd130x_device *ssd130x = bl_get_data(bdev);
920	int brightness = backlight_get_brightness(bdev);
921	int ret;
922
923	ssd130x->contrast = brightness;
924
925	ret = ssd130x_write_cmd(ssd130x, 1, SSD130X_CONTRAST);
926	if (ret < 0)
927		return ret;
928
929	ret = ssd130x_write_cmd(ssd130x, 1, ssd130x->contrast);
930	if (ret < 0)
931		return ret;
932
933	return 0;
934}
935
936static const struct backlight_ops ssd130xfb_bl_ops = {
937	.update_status	= ssd130x_update_bl,
938};
939
940static void ssd130x_parse_properties(struct ssd130x_device *ssd130x)
941{
942	struct device *dev = ssd130x->dev;
943
944	if (device_property_read_u32(dev, "solomon,width", &ssd130x->width))
945		ssd130x->width = ssd130x->device_info->default_width;
946
947	if (device_property_read_u32(dev, "solomon,height", &ssd130x->height))
948		ssd130x->height = ssd130x->device_info->default_height;
949
950	if (device_property_read_u32(dev, "solomon,page-offset", &ssd130x->page_offset))
951		ssd130x->page_offset = 1;
952
953	if (device_property_read_u32(dev, "solomon,col-offset", &ssd130x->col_offset))
954		ssd130x->col_offset = 0;
955
956	if (device_property_read_u32(dev, "solomon,com-offset", &ssd130x->com_offset))
957		ssd130x->com_offset = 0;
958
959	if (device_property_read_u32(dev, "solomon,prechargep1", &ssd130x->prechargep1))
960		ssd130x->prechargep1 = 2;
961
962	if (device_property_read_u32(dev, "solomon,prechargep2", &ssd130x->prechargep2))
963		ssd130x->prechargep2 = 2;
964
965	if (!device_property_read_u8_array(dev, "solomon,lookup-table",
966					   ssd130x->lookup_table,
967					   ARRAY_SIZE(ssd130x->lookup_table)))
968		ssd130x->lookup_table_set = 1;
969
970	ssd130x->seg_remap = !device_property_read_bool(dev, "solomon,segment-no-remap");
971	ssd130x->com_seq = device_property_read_bool(dev, "solomon,com-seq");
972	ssd130x->com_lrremap = device_property_read_bool(dev, "solomon,com-lrremap");
973	ssd130x->com_invdir = device_property_read_bool(dev, "solomon,com-invdir");
974	ssd130x->area_color_enable =
975		device_property_read_bool(dev, "solomon,area-color-enable");
976	ssd130x->low_power = device_property_read_bool(dev, "solomon,low-power");
977
978	ssd130x->contrast = 127;
979	ssd130x->vcomh = ssd130x->device_info->default_vcomh;
980
981	/* Setup display timing */
982	if (device_property_read_u32(dev, "solomon,dclk-div", &ssd130x->dclk_div))
983		ssd130x->dclk_div = ssd130x->device_info->default_dclk_div;
984	if (device_property_read_u32(dev, "solomon,dclk-frq", &ssd130x->dclk_frq))
985		ssd130x->dclk_frq = ssd130x->device_info->default_dclk_frq;
986}
987
988static int ssd130x_init_modeset(struct ssd130x_device *ssd130x)
989{
990	struct drm_display_mode *mode = &ssd130x->mode;
991	struct device *dev = ssd130x->dev;
992	struct drm_device *drm = &ssd130x->drm;
993	unsigned long max_width, max_height;
994	struct drm_plane *primary_plane;
995	struct drm_crtc *crtc;
996	struct drm_encoder *encoder;
997	struct drm_connector *connector;
998	int ret;
999
1000	/*
1001	 * Modesetting
1002	 */
1003
1004	ret = drmm_mode_config_init(drm);
1005	if (ret) {
1006		dev_err(dev, "DRM mode config init failed: %d\n", ret);
1007		return ret;
1008	}
1009
1010	mode->type = DRM_MODE_TYPE_DRIVER;
1011	mode->clock = 1;
1012	mode->hdisplay = mode->htotal = ssd130x->width;
1013	mode->hsync_start = mode->hsync_end = ssd130x->width;
1014	mode->vdisplay = mode->vtotal = ssd130x->height;
1015	mode->vsync_start = mode->vsync_end = ssd130x->height;
1016	mode->width_mm = 27;
1017	mode->height_mm = 27;
1018
1019	max_width = max_t(unsigned long, mode->hdisplay, DRM_SHADOW_PLANE_MAX_WIDTH);
1020	max_height = max_t(unsigned long, mode->vdisplay, DRM_SHADOW_PLANE_MAX_HEIGHT);
1021
1022	drm->mode_config.min_width = mode->hdisplay;
1023	drm->mode_config.max_width = max_width;
1024	drm->mode_config.min_height = mode->vdisplay;
1025	drm->mode_config.max_height = max_height;
1026	drm->mode_config.preferred_depth = 24;
1027	drm->mode_config.funcs = &ssd130x_mode_config_funcs;
1028
1029	/* Primary plane */
1030
1031	primary_plane = &ssd130x->primary_plane;
1032	ret = drm_universal_plane_init(drm, primary_plane, 0, &ssd130x_primary_plane_funcs,
1033				       ssd130x_formats, ARRAY_SIZE(ssd130x_formats),
1034				       NULL, DRM_PLANE_TYPE_PRIMARY, NULL);
1035	if (ret) {
1036		dev_err(dev, "DRM primary plane init failed: %d\n", ret);
1037		return ret;
1038	}
1039
1040	drm_plane_helper_add(primary_plane, &ssd130x_primary_plane_helper_funcs);
1041
1042	drm_plane_enable_fb_damage_clips(primary_plane);
1043
1044	/* CRTC */
1045
1046	crtc = &ssd130x->crtc;
1047	ret = drm_crtc_init_with_planes(drm, crtc, primary_plane, NULL,
1048					&ssd130x_crtc_funcs, NULL);
1049	if (ret) {
1050		dev_err(dev, "DRM crtc init failed: %d\n", ret);
1051		return ret;
1052	}
1053
1054	drm_crtc_helper_add(crtc, &ssd130x_crtc_helper_funcs);
1055
1056	/* Encoder */
1057
1058	encoder = &ssd130x->encoder;
1059	ret = drm_encoder_init(drm, encoder, &ssd130x_encoder_funcs,
1060			       DRM_MODE_ENCODER_NONE, NULL);
1061	if (ret) {
1062		dev_err(dev, "DRM encoder init failed: %d\n", ret);
1063		return ret;
1064	}
1065
1066	drm_encoder_helper_add(encoder, &ssd130x_encoder_helper_funcs);
1067
1068	encoder->possible_crtcs = drm_crtc_mask(crtc);
1069
1070	/* Connector */
1071
1072	connector = &ssd130x->connector;
1073	ret = drm_connector_init(drm, connector, &ssd130x_connector_funcs,
1074				 DRM_MODE_CONNECTOR_Unknown);
1075	if (ret) {
1076		dev_err(dev, "DRM connector init failed: %d\n", ret);
1077		return ret;
1078	}
1079
1080	drm_connector_helper_add(connector, &ssd130x_connector_helper_funcs);
1081
1082	ret = drm_connector_attach_encoder(connector, encoder);
1083	if (ret) {
1084		dev_err(dev, "DRM attach connector to encoder failed: %d\n", ret);
1085		return ret;
1086	}
1087
1088	drm_mode_config_reset(drm);
1089
1090	return 0;
1091}
1092
1093static int ssd130x_get_resources(struct ssd130x_device *ssd130x)
1094{
1095	struct device *dev = ssd130x->dev;
1096
1097	ssd130x->reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
1098	if (IS_ERR(ssd130x->reset))
1099		return dev_err_probe(dev, PTR_ERR(ssd130x->reset),
1100				     "Failed to get reset gpio\n");
1101
1102	ssd130x->vcc_reg = devm_regulator_get(dev, "vcc");
1103	if (IS_ERR(ssd130x->vcc_reg))
1104		return dev_err_probe(dev, PTR_ERR(ssd130x->vcc_reg),
1105				     "Failed to get VCC regulator\n");
1106
1107	return 0;
1108}
1109
1110struct ssd130x_device *ssd130x_probe(struct device *dev, struct regmap *regmap)
1111{
1112	struct ssd130x_device *ssd130x;
1113	struct backlight_device *bl;
1114	struct drm_device *drm;
1115	int ret;
1116
1117	ssd130x = devm_drm_dev_alloc(dev, &ssd130x_drm_driver,
1118				     struct ssd130x_device, drm);
1119	if (IS_ERR(ssd130x))
1120		return ERR_PTR(dev_err_probe(dev, PTR_ERR(ssd130x),
1121					     "Failed to allocate DRM device\n"));
1122
1123	drm = &ssd130x->drm;
1124
1125	ssd130x->dev = dev;
1126	ssd130x->regmap = regmap;
1127	ssd130x->device_info = device_get_match_data(dev);
1128
1129	if (ssd130x->device_info->page_mode_only)
1130		ssd130x->page_address_mode = 1;
1131
1132	ssd130x_parse_properties(ssd130x);
1133
1134	ret = ssd130x_get_resources(ssd130x);
1135	if (ret)
1136		return ERR_PTR(ret);
1137
1138	bl = devm_backlight_device_register(dev, dev_name(dev), dev, ssd130x,
1139					    &ssd130xfb_bl_ops, NULL);
1140	if (IS_ERR(bl))
1141		return ERR_PTR(dev_err_probe(dev, PTR_ERR(bl),
1142					     "Unable to register backlight device\n"));
1143
1144	bl->props.brightness = ssd130x->contrast;
1145	bl->props.max_brightness = MAX_CONTRAST;
1146	ssd130x->bl_dev = bl;
1147
1148	ret = ssd130x_init_modeset(ssd130x);
1149	if (ret)
1150		return ERR_PTR(ret);
1151
1152	ret = drm_dev_register(drm, 0);
1153	if (ret)
1154		return ERR_PTR(dev_err_probe(dev, ret, "DRM device register failed\n"));
1155
1156	drm_fbdev_generic_setup(drm, 32);
1157
1158	return ssd130x;
1159}
1160EXPORT_SYMBOL_GPL(ssd130x_probe);
1161
1162void ssd130x_remove(struct ssd130x_device *ssd130x)
1163{
1164	drm_dev_unplug(&ssd130x->drm);
1165}
1166EXPORT_SYMBOL_GPL(ssd130x_remove);
1167
1168void ssd130x_shutdown(struct ssd130x_device *ssd130x)
1169{
1170	drm_atomic_helper_shutdown(&ssd130x->drm);
1171}
1172EXPORT_SYMBOL_GPL(ssd130x_shutdown);
1173
1174MODULE_DESCRIPTION(DRIVER_DESC);
1175MODULE_AUTHOR("Javier Martinez Canillas <javierm@redhat.com>");
1176MODULE_LICENSE("GPL v2");
1177