1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Driver for the Solomon SSD1307 OLED controller
4 *
5 * Copyright 2012 Free Electrons
6 */
7
8 #include <linux/backlight.h>
9 #include <linux/delay.h>
10 #include <linux/fb.h>
11 #include <linux/gpio/consumer.h>
12 #include <linux/i2c.h>
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/property.h>
16 #include <linux/pwm.h>
17 #include <linux/uaccess.h>
18 #include <linux/regulator/consumer.h>
19
20 #define SSD1307FB_DATA 0x40
21 #define SSD1307FB_COMMAND 0x80
22
23 #define SSD1307FB_SET_ADDRESS_MODE 0x20
24 #define SSD1307FB_SET_ADDRESS_MODE_HORIZONTAL (0x00)
25 #define SSD1307FB_SET_ADDRESS_MODE_VERTICAL (0x01)
26 #define SSD1307FB_SET_ADDRESS_MODE_PAGE (0x02)
27 #define SSD1307FB_SET_COL_RANGE 0x21
28 #define SSD1307FB_SET_PAGE_RANGE 0x22
29 #define SSD1307FB_CONTRAST 0x81
30 #define SSD1307FB_SET_LOOKUP_TABLE 0x91
31 #define SSD1307FB_CHARGE_PUMP 0x8d
32 #define SSD1307FB_SEG_REMAP_ON 0xa1
33 #define SSD1307FB_DISPLAY_OFF 0xae
34 #define SSD1307FB_SET_MULTIPLEX_RATIO 0xa8
35 #define SSD1307FB_DISPLAY_ON 0xaf
36 #define SSD1307FB_START_PAGE_ADDRESS 0xb0
37 #define SSD1307FB_SET_DISPLAY_OFFSET 0xd3
38 #define SSD1307FB_SET_CLOCK_FREQ 0xd5
39 #define SSD1307FB_SET_AREA_COLOR_MODE 0xd8
40 #define SSD1307FB_SET_PRECHARGE_PERIOD 0xd9
41 #define SSD1307FB_SET_COM_PINS_CONFIG 0xda
42 #define SSD1307FB_SET_VCOMH 0xdb
43
44 #define MAX_CONTRAST 255
45
46 #define REFRESHRATE 1
47
48 static u_int refreshrate = REFRESHRATE;
49 module_param(refreshrate, uint, 0);
50
51 struct ssd1307fb_deviceinfo {
52 u32 default_vcomh;
53 u32 default_dclk_div;
54 u32 default_dclk_frq;
55 int need_pwm;
56 int need_chargepump;
57 };
58
59 struct ssd1307fb_par {
60 unsigned area_color_enable : 1;
61 unsigned com_invdir : 1;
62 unsigned com_lrremap : 1;
63 unsigned com_seq : 1;
64 unsigned lookup_table_set : 1;
65 unsigned low_power : 1;
66 unsigned seg_remap : 1;
67 u32 com_offset;
68 u32 contrast;
69 u32 dclk_div;
70 u32 dclk_frq;
71 const struct ssd1307fb_deviceinfo *device_info;
72 struct i2c_client *client;
73 u32 height;
74 struct fb_info *info;
75 u8 lookup_table[4];
76 u32 page_offset;
77 u32 col_offset;
78 u32 prechargep1;
79 u32 prechargep2;
80 struct pwm_device *pwm;
81 struct gpio_desc *reset;
82 struct regulator *vbat_reg;
83 u32 vcomh;
84 u32 width;
85 /* Cached address ranges */
86 u8 col_start;
87 u8 col_end;
88 u8 page_start;
89 u8 page_end;
90 };
91
92 struct ssd1307fb_array {
93 u8 type;
94 u8 data[];
95 };
96
97 static const struct fb_fix_screeninfo ssd1307fb_fix = {
98 .id = "Solomon SSD1307",
99 .type = FB_TYPE_PACKED_PIXELS,
100 .visual = FB_VISUAL_MONO10,
101 .xpanstep = 0,
102 .ypanstep = 0,
103 .ywrapstep = 0,
104 .accel = FB_ACCEL_NONE,
105 };
106
107 static const struct fb_var_screeninfo ssd1307fb_var = {
108 .bits_per_pixel = 1,
109 .red = { .length = 1 },
110 .green = { .length = 1 },
111 .blue = { .length = 1 },
112 };
113
ssd1307fb_alloc_array(u32 len,u8 type)114 static struct ssd1307fb_array *ssd1307fb_alloc_array(u32 len, u8 type)
115 {
116 struct ssd1307fb_array *array;
117
118 array = kzalloc(sizeof(struct ssd1307fb_array) + len, GFP_KERNEL);
119 if (!array)
120 return NULL;
121
122 array->type = type;
123
124 return array;
125 }
126
ssd1307fb_write_array(struct i2c_client * client,struct ssd1307fb_array * array,u32 len)127 static int ssd1307fb_write_array(struct i2c_client *client,
128 struct ssd1307fb_array *array, u32 len)
129 {
130 int ret;
131
132 len += sizeof(struct ssd1307fb_array);
133
134 ret = i2c_master_send(client, (u8 *)array, len);
135 if (ret != len) {
136 dev_err(&client->dev, "Couldn't send I2C command.\n");
137 return ret;
138 }
139
140 return 0;
141 }
142
ssd1307fb_write_cmd(struct i2c_client * client,u8 cmd)143 static inline int ssd1307fb_write_cmd(struct i2c_client *client, u8 cmd)
144 {
145 struct ssd1307fb_array *array;
146 int ret;
147
148 array = ssd1307fb_alloc_array(1, SSD1307FB_COMMAND);
149 if (!array)
150 return -ENOMEM;
151
152 array->data[0] = cmd;
153
154 ret = ssd1307fb_write_array(client, array, 1);
155 kfree(array);
156
157 return ret;
158 }
159
ssd1307fb_set_col_range(struct ssd1307fb_par * par,u8 col_start,u8 cols)160 static int ssd1307fb_set_col_range(struct ssd1307fb_par *par, u8 col_start,
161 u8 cols)
162 {
163 u8 col_end = col_start + cols - 1;
164 int ret;
165
166 if (col_start == par->col_start && col_end == par->col_end)
167 return 0;
168
169 ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_COL_RANGE);
170 if (ret < 0)
171 return ret;
172
173 ret = ssd1307fb_write_cmd(par->client, col_start);
174 if (ret < 0)
175 return ret;
176
177 ret = ssd1307fb_write_cmd(par->client, col_end);
178 if (ret < 0)
179 return ret;
180
181 par->col_start = col_start;
182 par->col_end = col_end;
183 return 0;
184 }
185
ssd1307fb_set_page_range(struct ssd1307fb_par * par,u8 page_start,u8 pages)186 static int ssd1307fb_set_page_range(struct ssd1307fb_par *par, u8 page_start,
187 u8 pages)
188 {
189 u8 page_end = page_start + pages - 1;
190 int ret;
191
192 if (page_start == par->page_start && page_end == par->page_end)
193 return 0;
194
195 ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_PAGE_RANGE);
196 if (ret < 0)
197 return ret;
198
199 ret = ssd1307fb_write_cmd(par->client, page_start);
200 if (ret < 0)
201 return ret;
202
203 ret = ssd1307fb_write_cmd(par->client, page_end);
204 if (ret < 0)
205 return ret;
206
207 par->page_start = page_start;
208 par->page_end = page_end;
209 return 0;
210 }
211
ssd1307fb_update_rect(struct ssd1307fb_par * par,unsigned int x,unsigned int y,unsigned int width,unsigned int height)212 static int ssd1307fb_update_rect(struct ssd1307fb_par *par, unsigned int x,
213 unsigned int y, unsigned int width,
214 unsigned int height)
215 {
216 struct ssd1307fb_array *array;
217 u8 *vmem = par->info->screen_buffer;
218 unsigned int line_length = par->info->fix.line_length;
219 unsigned int pages = DIV_ROUND_UP(y % 8 + height, 8);
220 u32 array_idx = 0;
221 int ret, i, j, k;
222
223 array = ssd1307fb_alloc_array(width * pages, SSD1307FB_DATA);
224 if (!array)
225 return -ENOMEM;
226
227 /*
228 * The screen is divided in pages, each having a height of 8
229 * pixels, and the width of the screen. When sending a byte of
230 * data to the controller, it gives the 8 bits for the current
231 * column. I.e, the first byte are the 8 bits of the first
232 * column, then the 8 bits for the second column, etc.
233 *
234 *
235 * Representation of the screen, assuming it is 5 bits
236 * wide. Each letter-number combination is a bit that controls
237 * one pixel.
238 *
239 * A0 A1 A2 A3 A4
240 * B0 B1 B2 B3 B4
241 * C0 C1 C2 C3 C4
242 * D0 D1 D2 D3 D4
243 * E0 E1 E2 E3 E4
244 * F0 F1 F2 F3 F4
245 * G0 G1 G2 G3 G4
246 * H0 H1 H2 H3 H4
247 *
248 * If you want to update this screen, you need to send 5 bytes:
249 * (1) A0 B0 C0 D0 E0 F0 G0 H0
250 * (2) A1 B1 C1 D1 E1 F1 G1 H1
251 * (3) A2 B2 C2 D2 E2 F2 G2 H2
252 * (4) A3 B3 C3 D3 E3 F3 G3 H3
253 * (5) A4 B4 C4 D4 E4 F4 G4 H4
254 */
255
256 ret = ssd1307fb_set_col_range(par, par->col_offset + x, width);
257 if (ret < 0)
258 goto out_free;
259
260 ret = ssd1307fb_set_page_range(par, par->page_offset + y / 8, pages);
261 if (ret < 0)
262 goto out_free;
263
264 for (i = y / 8; i < y / 8 + pages; i++) {
265 int m = 8;
266
267 /* Last page may be partial */
268 if (8 * (i + 1) > par->height)
269 m = par->height % 8;
270 for (j = x; j < x + width; j++) {
271 u8 data = 0;
272
273 for (k = 0; k < m; k++) {
274 u8 byte = vmem[(8 * i + k) * line_length +
275 j / 8];
276 u8 bit = (byte >> (j % 8)) & 1;
277 data |= bit << k;
278 }
279 array->data[array_idx++] = data;
280 }
281 }
282
283 ret = ssd1307fb_write_array(par->client, array, width * pages);
284
285 out_free:
286 kfree(array);
287 return ret;
288 }
289
ssd1307fb_update_display(struct ssd1307fb_par * par)290 static int ssd1307fb_update_display(struct ssd1307fb_par *par)
291 {
292 return ssd1307fb_update_rect(par, 0, 0, par->width, par->height);
293 }
294
ssd1307fb_write(struct fb_info * info,const char __user * buf,size_t count,loff_t * ppos)295 static ssize_t ssd1307fb_write(struct fb_info *info, const char __user *buf,
296 size_t count, loff_t *ppos)
297 {
298 struct ssd1307fb_par *par = info->par;
299 unsigned long total_size;
300 unsigned long p = *ppos;
301 void *dst;
302 int ret;
303
304 total_size = info->fix.smem_len;
305
306 if (p > total_size)
307 return -EINVAL;
308
309 if (count + p > total_size)
310 count = total_size - p;
311
312 if (!count)
313 return -EINVAL;
314
315 dst = info->screen_buffer + p;
316
317 if (copy_from_user(dst, buf, count))
318 return -EFAULT;
319
320 ret = ssd1307fb_update_display(par);
321 if (ret < 0)
322 return ret;
323
324 *ppos += count;
325
326 return count;
327 }
328
ssd1307fb_blank(int blank_mode,struct fb_info * info)329 static int ssd1307fb_blank(int blank_mode, struct fb_info *info)
330 {
331 struct ssd1307fb_par *par = info->par;
332
333 if (blank_mode != FB_BLANK_UNBLANK)
334 return ssd1307fb_write_cmd(par->client, SSD1307FB_DISPLAY_OFF);
335 else
336 return ssd1307fb_write_cmd(par->client, SSD1307FB_DISPLAY_ON);
337 }
338
ssd1307fb_fillrect(struct fb_info * info,const struct fb_fillrect * rect)339 static void ssd1307fb_fillrect(struct fb_info *info, const struct fb_fillrect *rect)
340 {
341 struct ssd1307fb_par *par = info->par;
342 sys_fillrect(info, rect);
343 ssd1307fb_update_rect(par, rect->dx, rect->dy, rect->width,
344 rect->height);
345 }
346
ssd1307fb_copyarea(struct fb_info * info,const struct fb_copyarea * area)347 static void ssd1307fb_copyarea(struct fb_info *info, const struct fb_copyarea *area)
348 {
349 struct ssd1307fb_par *par = info->par;
350 sys_copyarea(info, area);
351 ssd1307fb_update_rect(par, area->dx, area->dy, area->width,
352 area->height);
353 }
354
ssd1307fb_imageblit(struct fb_info * info,const struct fb_image * image)355 static void ssd1307fb_imageblit(struct fb_info *info, const struct fb_image *image)
356 {
357 struct ssd1307fb_par *par = info->par;
358 sys_imageblit(info, image);
359 ssd1307fb_update_rect(par, image->dx, image->dy, image->width,
360 image->height);
361 }
362
363 static const struct fb_ops ssd1307fb_ops = {
364 .owner = THIS_MODULE,
365 .fb_read = fb_sys_read,
366 .fb_write = ssd1307fb_write,
367 .fb_blank = ssd1307fb_blank,
368 .fb_fillrect = ssd1307fb_fillrect,
369 .fb_copyarea = ssd1307fb_copyarea,
370 .fb_imageblit = ssd1307fb_imageblit,
371 };
372
ssd1307fb_deferred_io(struct fb_info * info,struct list_head * pagelist)373 static void ssd1307fb_deferred_io(struct fb_info *info,
374 struct list_head *pagelist)
375 {
376 ssd1307fb_update_display(info->par);
377 }
378
ssd1307fb_init(struct ssd1307fb_par * par)379 static int ssd1307fb_init(struct ssd1307fb_par *par)
380 {
381 struct pwm_state pwmstate;
382 int ret;
383 u32 precharge, dclk, com_invdir, compins;
384
385 if (par->device_info->need_pwm) {
386 par->pwm = pwm_get(&par->client->dev, NULL);
387 if (IS_ERR(par->pwm)) {
388 dev_err(&par->client->dev, "Could not get PWM from device tree!\n");
389 return PTR_ERR(par->pwm);
390 }
391
392 pwm_init_state(par->pwm, &pwmstate);
393 pwm_set_relative_duty_cycle(&pwmstate, 50, 100);
394 pwm_apply_state(par->pwm, &pwmstate);
395
396 /* Enable the PWM */
397 pwm_enable(par->pwm);
398
399 dev_dbg(&par->client->dev, "Using PWM%d with a %lluns period.\n",
400 par->pwm->pwm, pwm_get_period(par->pwm));
401 }
402
403 /* Set initial contrast */
404 ret = ssd1307fb_write_cmd(par->client, SSD1307FB_CONTRAST);
405 if (ret < 0)
406 return ret;
407
408 ret = ssd1307fb_write_cmd(par->client, par->contrast);
409 if (ret < 0)
410 return ret;
411
412 /* Set segment re-map */
413 if (par->seg_remap) {
414 ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SEG_REMAP_ON);
415 if (ret < 0)
416 return ret;
417 }
418
419 /* Set COM direction */
420 com_invdir = 0xc0 | par->com_invdir << 3;
421 ret = ssd1307fb_write_cmd(par->client, com_invdir);
422 if (ret < 0)
423 return ret;
424
425 /* Set multiplex ratio value */
426 ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_MULTIPLEX_RATIO);
427 if (ret < 0)
428 return ret;
429
430 ret = ssd1307fb_write_cmd(par->client, par->height - 1);
431 if (ret < 0)
432 return ret;
433
434 /* set display offset value */
435 ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_DISPLAY_OFFSET);
436 if (ret < 0)
437 return ret;
438
439 ret = ssd1307fb_write_cmd(par->client, par->com_offset);
440 if (ret < 0)
441 return ret;
442
443 /* Set clock frequency */
444 ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_CLOCK_FREQ);
445 if (ret < 0)
446 return ret;
447
448 dclk = ((par->dclk_div - 1) & 0xf) | (par->dclk_frq & 0xf) << 4;
449 ret = ssd1307fb_write_cmd(par->client, dclk);
450 if (ret < 0)
451 return ret;
452
453 /* Set Set Area Color Mode ON/OFF & Low Power Display Mode */
454 if (par->area_color_enable || par->low_power) {
455 u32 mode;
456
457 ret = ssd1307fb_write_cmd(par->client,
458 SSD1307FB_SET_AREA_COLOR_MODE);
459 if (ret < 0)
460 return ret;
461
462 mode = (par->area_color_enable ? 0x30 : 0) |
463 (par->low_power ? 5 : 0);
464 ret = ssd1307fb_write_cmd(par->client, mode);
465 if (ret < 0)
466 return ret;
467 }
468
469 /* Set precharge period in number of ticks from the internal clock */
470 ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_PRECHARGE_PERIOD);
471 if (ret < 0)
472 return ret;
473
474 precharge = (par->prechargep1 & 0xf) | (par->prechargep2 & 0xf) << 4;
475 ret = ssd1307fb_write_cmd(par->client, precharge);
476 if (ret < 0)
477 return ret;
478
479 /* Set COM pins configuration */
480 ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_COM_PINS_CONFIG);
481 if (ret < 0)
482 return ret;
483
484 compins = 0x02 | !par->com_seq << 4 | par->com_lrremap << 5;
485 ret = ssd1307fb_write_cmd(par->client, compins);
486 if (ret < 0)
487 return ret;
488
489 /* Set VCOMH */
490 ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_VCOMH);
491 if (ret < 0)
492 return ret;
493
494 ret = ssd1307fb_write_cmd(par->client, par->vcomh);
495 if (ret < 0)
496 return ret;
497
498 /* Turn on the DC-DC Charge Pump */
499 ret = ssd1307fb_write_cmd(par->client, SSD1307FB_CHARGE_PUMP);
500 if (ret < 0)
501 return ret;
502
503 ret = ssd1307fb_write_cmd(par->client,
504 BIT(4) | (par->device_info->need_chargepump ? BIT(2) : 0));
505 if (ret < 0)
506 return ret;
507
508 /* Set lookup table */
509 if (par->lookup_table_set) {
510 int i;
511
512 ret = ssd1307fb_write_cmd(par->client,
513 SSD1307FB_SET_LOOKUP_TABLE);
514 if (ret < 0)
515 return ret;
516
517 for (i = 0; i < ARRAY_SIZE(par->lookup_table); ++i) {
518 u8 val = par->lookup_table[i];
519
520 if (val < 31 || val > 63)
521 dev_warn(&par->client->dev,
522 "lookup table index %d value out of range 31 <= %d <= 63\n",
523 i, val);
524 ret = ssd1307fb_write_cmd(par->client, val);
525 if (ret < 0)
526 return ret;
527 }
528 }
529
530 /* Switch to horizontal addressing mode */
531 ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_ADDRESS_MODE);
532 if (ret < 0)
533 return ret;
534
535 ret = ssd1307fb_write_cmd(par->client,
536 SSD1307FB_SET_ADDRESS_MODE_HORIZONTAL);
537 if (ret < 0)
538 return ret;
539
540 /* Clear the screen */
541 ret = ssd1307fb_update_display(par);
542 if (ret < 0)
543 return ret;
544
545 /* Turn on the display */
546 ret = ssd1307fb_write_cmd(par->client, SSD1307FB_DISPLAY_ON);
547 if (ret < 0)
548 return ret;
549
550 return 0;
551 }
552
ssd1307fb_update_bl(struct backlight_device * bdev)553 static int ssd1307fb_update_bl(struct backlight_device *bdev)
554 {
555 struct ssd1307fb_par *par = bl_get_data(bdev);
556 int ret;
557 int brightness = bdev->props.brightness;
558
559 par->contrast = brightness;
560
561 ret = ssd1307fb_write_cmd(par->client, SSD1307FB_CONTRAST);
562 if (ret < 0)
563 return ret;
564 ret = ssd1307fb_write_cmd(par->client, par->contrast);
565 if (ret < 0)
566 return ret;
567 return 0;
568 }
569
ssd1307fb_get_brightness(struct backlight_device * bdev)570 static int ssd1307fb_get_brightness(struct backlight_device *bdev)
571 {
572 struct ssd1307fb_par *par = bl_get_data(bdev);
573
574 return par->contrast;
575 }
576
ssd1307fb_check_fb(struct backlight_device * bdev,struct fb_info * info)577 static int ssd1307fb_check_fb(struct backlight_device *bdev,
578 struct fb_info *info)
579 {
580 return (info->bl_dev == bdev);
581 }
582
583 static const struct backlight_ops ssd1307fb_bl_ops = {
584 .options = BL_CORE_SUSPENDRESUME,
585 .update_status = ssd1307fb_update_bl,
586 .get_brightness = ssd1307fb_get_brightness,
587 .check_fb = ssd1307fb_check_fb,
588 };
589
590 static struct ssd1307fb_deviceinfo ssd1307fb_ssd1305_deviceinfo = {
591 .default_vcomh = 0x34,
592 .default_dclk_div = 1,
593 .default_dclk_frq = 7,
594 };
595
596 static struct ssd1307fb_deviceinfo ssd1307fb_ssd1306_deviceinfo = {
597 .default_vcomh = 0x20,
598 .default_dclk_div = 1,
599 .default_dclk_frq = 8,
600 .need_chargepump = 1,
601 };
602
603 static struct ssd1307fb_deviceinfo ssd1307fb_ssd1307_deviceinfo = {
604 .default_vcomh = 0x20,
605 .default_dclk_div = 2,
606 .default_dclk_frq = 12,
607 .need_pwm = 1,
608 };
609
610 static struct ssd1307fb_deviceinfo ssd1307fb_ssd1309_deviceinfo = {
611 .default_vcomh = 0x34,
612 .default_dclk_div = 1,
613 .default_dclk_frq = 10,
614 };
615
616 static const struct of_device_id ssd1307fb_of_match[] = {
617 {
618 .compatible = "solomon,ssd1305fb-i2c",
619 .data = (void *)&ssd1307fb_ssd1305_deviceinfo,
620 },
621 {
622 .compatible = "solomon,ssd1306fb-i2c",
623 .data = (void *)&ssd1307fb_ssd1306_deviceinfo,
624 },
625 {
626 .compatible = "solomon,ssd1307fb-i2c",
627 .data = (void *)&ssd1307fb_ssd1307_deviceinfo,
628 },
629 {
630 .compatible = "solomon,ssd1309fb-i2c",
631 .data = (void *)&ssd1307fb_ssd1309_deviceinfo,
632 },
633 {},
634 };
635 MODULE_DEVICE_TABLE(of, ssd1307fb_of_match);
636
ssd1307fb_probe(struct i2c_client * client)637 static int ssd1307fb_probe(struct i2c_client *client)
638 {
639 struct device *dev = &client->dev;
640 struct backlight_device *bl;
641 char bl_name[12];
642 struct fb_info *info;
643 struct fb_deferred_io *ssd1307fb_defio;
644 u32 vmem_size;
645 struct ssd1307fb_par *par;
646 void *vmem;
647 int ret;
648
649 info = framebuffer_alloc(sizeof(struct ssd1307fb_par), dev);
650 if (!info)
651 return -ENOMEM;
652
653 par = info->par;
654 par->info = info;
655 par->client = client;
656
657 par->device_info = device_get_match_data(dev);
658
659 par->reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
660 if (IS_ERR(par->reset)) {
661 dev_err(dev, "failed to get reset gpio: %ld\n",
662 PTR_ERR(par->reset));
663 ret = PTR_ERR(par->reset);
664 goto fb_alloc_error;
665 }
666
667 par->vbat_reg = devm_regulator_get_optional(dev, "vbat");
668 if (IS_ERR(par->vbat_reg)) {
669 ret = PTR_ERR(par->vbat_reg);
670 if (ret == -ENODEV) {
671 par->vbat_reg = NULL;
672 } else {
673 dev_err(dev, "failed to get VBAT regulator: %d\n", ret);
674 goto fb_alloc_error;
675 }
676 }
677
678 if (device_property_read_u32(dev, "solomon,width", &par->width))
679 par->width = 96;
680
681 if (device_property_read_u32(dev, "solomon,height", &par->height))
682 par->height = 16;
683
684 if (device_property_read_u32(dev, "solomon,page-offset", &par->page_offset))
685 par->page_offset = 1;
686
687 if (device_property_read_u32(dev, "solomon,col-offset", &par->col_offset))
688 par->col_offset = 0;
689
690 if (device_property_read_u32(dev, "solomon,com-offset", &par->com_offset))
691 par->com_offset = 0;
692
693 if (device_property_read_u32(dev, "solomon,prechargep1", &par->prechargep1))
694 par->prechargep1 = 2;
695
696 if (device_property_read_u32(dev, "solomon,prechargep2", &par->prechargep2))
697 par->prechargep2 = 2;
698
699 if (!device_property_read_u8_array(dev, "solomon,lookup-table",
700 par->lookup_table,
701 ARRAY_SIZE(par->lookup_table)))
702 par->lookup_table_set = 1;
703
704 par->seg_remap = !device_property_read_bool(dev, "solomon,segment-no-remap");
705 par->com_seq = device_property_read_bool(dev, "solomon,com-seq");
706 par->com_lrremap = device_property_read_bool(dev, "solomon,com-lrremap");
707 par->com_invdir = device_property_read_bool(dev, "solomon,com-invdir");
708 par->area_color_enable =
709 device_property_read_bool(dev, "solomon,area-color-enable");
710 par->low_power = device_property_read_bool(dev, "solomon,low-power");
711
712 par->contrast = 127;
713 par->vcomh = par->device_info->default_vcomh;
714
715 /* Setup display timing */
716 if (device_property_read_u32(dev, "solomon,dclk-div", &par->dclk_div))
717 par->dclk_div = par->device_info->default_dclk_div;
718 if (device_property_read_u32(dev, "solomon,dclk-frq", &par->dclk_frq))
719 par->dclk_frq = par->device_info->default_dclk_frq;
720
721 vmem_size = DIV_ROUND_UP(par->width, 8) * par->height;
722
723 vmem = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
724 get_order(vmem_size));
725 if (!vmem) {
726 dev_err(dev, "Couldn't allocate graphical memory.\n");
727 ret = -ENOMEM;
728 goto fb_alloc_error;
729 }
730
731 ssd1307fb_defio = devm_kzalloc(dev, sizeof(*ssd1307fb_defio),
732 GFP_KERNEL);
733 if (!ssd1307fb_defio) {
734 dev_err(dev, "Couldn't allocate deferred io.\n");
735 ret = -ENOMEM;
736 goto fb_alloc_error;
737 }
738
739 ssd1307fb_defio->delay = HZ / refreshrate;
740 ssd1307fb_defio->deferred_io = ssd1307fb_deferred_io;
741
742 info->fbops = &ssd1307fb_ops;
743 info->fix = ssd1307fb_fix;
744 info->fix.line_length = DIV_ROUND_UP(par->width, 8);
745 info->fbdefio = ssd1307fb_defio;
746
747 info->var = ssd1307fb_var;
748 info->var.xres = par->width;
749 info->var.xres_virtual = par->width;
750 info->var.yres = par->height;
751 info->var.yres_virtual = par->height;
752
753 info->screen_buffer = vmem;
754 info->fix.smem_start = __pa(vmem);
755 info->fix.smem_len = vmem_size;
756
757 fb_deferred_io_init(info);
758
759 i2c_set_clientdata(client, info);
760
761 if (par->reset) {
762 /* Reset the screen */
763 gpiod_set_value_cansleep(par->reset, 1);
764 udelay(4);
765 gpiod_set_value_cansleep(par->reset, 0);
766 udelay(4);
767 }
768
769 if (par->vbat_reg) {
770 ret = regulator_enable(par->vbat_reg);
771 if (ret) {
772 dev_err(dev, "failed to enable VBAT: %d\n", ret);
773 goto reset_oled_error;
774 }
775 }
776
777 ret = ssd1307fb_init(par);
778 if (ret)
779 goto regulator_enable_error;
780
781 ret = register_framebuffer(info);
782 if (ret) {
783 dev_err(dev, "Couldn't register the framebuffer\n");
784 goto panel_init_error;
785 }
786
787 snprintf(bl_name, sizeof(bl_name), "ssd1307fb%d", info->node);
788 bl = backlight_device_register(bl_name, dev, par, &ssd1307fb_bl_ops,
789 NULL);
790 if (IS_ERR(bl)) {
791 ret = PTR_ERR(bl);
792 dev_err(dev, "unable to register backlight device: %d\n", ret);
793 goto bl_init_error;
794 }
795
796 bl->props.brightness = par->contrast;
797 bl->props.max_brightness = MAX_CONTRAST;
798 info->bl_dev = bl;
799
800 dev_info(dev, "fb%d: %s framebuffer device registered, using %d bytes of video memory\n", info->node, info->fix.id, vmem_size);
801
802 return 0;
803
804 bl_init_error:
805 unregister_framebuffer(info);
806 panel_init_error:
807 if (par->device_info->need_pwm) {
808 pwm_disable(par->pwm);
809 pwm_put(par->pwm);
810 }
811 regulator_enable_error:
812 if (par->vbat_reg)
813 regulator_disable(par->vbat_reg);
814 reset_oled_error:
815 fb_deferred_io_cleanup(info);
816 fb_alloc_error:
817 framebuffer_release(info);
818 return ret;
819 }
820
ssd1307fb_remove(struct i2c_client * client)821 static int ssd1307fb_remove(struct i2c_client *client)
822 {
823 struct fb_info *info = i2c_get_clientdata(client);
824 struct ssd1307fb_par *par = info->par;
825
826 ssd1307fb_write_cmd(par->client, SSD1307FB_DISPLAY_OFF);
827
828 backlight_device_unregister(info->bl_dev);
829
830 unregister_framebuffer(info);
831 if (par->device_info->need_pwm) {
832 pwm_disable(par->pwm);
833 pwm_put(par->pwm);
834 }
835 if (par->vbat_reg)
836 regulator_disable(par->vbat_reg);
837 fb_deferred_io_cleanup(info);
838 __free_pages(__va(info->fix.smem_start), get_order(info->fix.smem_len));
839 framebuffer_release(info);
840
841 return 0;
842 }
843
844 static const struct i2c_device_id ssd1307fb_i2c_id[] = {
845 { "ssd1305fb", 0 },
846 { "ssd1306fb", 0 },
847 { "ssd1307fb", 0 },
848 { "ssd1309fb", 0 },
849 { }
850 };
851 MODULE_DEVICE_TABLE(i2c, ssd1307fb_i2c_id);
852
853 static struct i2c_driver ssd1307fb_driver = {
854 .probe_new = ssd1307fb_probe,
855 .remove = ssd1307fb_remove,
856 .id_table = ssd1307fb_i2c_id,
857 .driver = {
858 .name = "ssd1307fb",
859 .of_match_table = ssd1307fb_of_match,
860 },
861 };
862
863 module_i2c_driver(ssd1307fb_driver);
864
865 MODULE_DESCRIPTION("FB driver for the Solomon SSD1307 OLED controller");
866 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
867 MODULE_LICENSE("GPL");
868
