1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Copyright (C) 2013 Noralf Tronnes
4 *
5 * This driver is inspired by:
6 * st7735fb.c, Copyright (C) 2011, Matt Porter
7 * broadsheetfb.c, Copyright (C) 2008, Jaya Kumar
8 */
9
10 #include <linux/module.h>
11 #include <linux/kernel.h>
12 #include <linux/errno.h>
13 #include <linux/string.h>
14 #include <linux/mm.h>
15 #include <linux/vmalloc.h>
16 #include <linux/slab.h>
17 #include <linux/init.h>
18 #include <linux/fb.h>
19 #include <linux/gpio/consumer.h>
20 #include <linux/spi/spi.h>
21 #include <linux/delay.h>
22 #include <linux/uaccess.h>
23 #include <linux/backlight.h>
24 #include <linux/platform_device.h>
25 #include <linux/property.h>
26 #include <linux/spinlock.h>
27
28 #include <video/mipi_display.h>
29
30 #include "fbtft.h"
31 #include "internal.h"
32
33 static unsigned long debug;
34 module_param(debug, ulong, 0000);
35 MODULE_PARM_DESC(debug, "override device debug level");
36
fbtft_write_buf_dc(struct fbtft_par * par,void * buf,size_t len,int dc)37 int fbtft_write_buf_dc(struct fbtft_par *par, void *buf, size_t len, int dc)
38 {
39 int ret;
40
41 gpiod_set_value(par->gpio.dc, dc);
42
43 ret = par->fbtftops.write(par, buf, len);
44 if (ret < 0)
45 dev_err(par->info->device,
46 "write() failed and returned %d\n", ret);
47 return ret;
48 }
49 EXPORT_SYMBOL(fbtft_write_buf_dc);
50
fbtft_dbg_hex(const struct device * dev,int groupsize,const void * buf,size_t len,const char * fmt,...)51 void fbtft_dbg_hex(const struct device *dev, int groupsize,
52 const void *buf, size_t len, const char *fmt, ...)
53 {
54 va_list args;
55 static char textbuf[512];
56 char *text = textbuf;
57 size_t text_len;
58
59 va_start(args, fmt);
60 text_len = vscnprintf(text, sizeof(textbuf), fmt, args);
61 va_end(args);
62
63 hex_dump_to_buffer(buf, len, 32, groupsize, text + text_len,
64 512 - text_len, false);
65
66 if (len > 32)
67 dev_info(dev, "%s ...\n", text);
68 else
69 dev_info(dev, "%s\n", text);
70 }
71 EXPORT_SYMBOL(fbtft_dbg_hex);
72
fbtft_request_one_gpio(struct fbtft_par * par,const char * name,int index,struct gpio_desc ** gpiop)73 static int fbtft_request_one_gpio(struct fbtft_par *par,
74 const char *name, int index,
75 struct gpio_desc **gpiop)
76 {
77 struct device *dev = par->info->device;
78
79 *gpiop = devm_gpiod_get_index_optional(dev, name, index,
80 GPIOD_OUT_LOW);
81 if (IS_ERR(*gpiop))
82 return dev_err_probe(dev, PTR_ERR(*gpiop), "Failed to request %s GPIO\n", name);
83
84 fbtft_par_dbg(DEBUG_REQUEST_GPIOS, par, "%s: '%s' GPIO\n",
85 __func__, name);
86
87 return 0;
88 }
89
fbtft_request_gpios(struct fbtft_par * par)90 static int fbtft_request_gpios(struct fbtft_par *par)
91 {
92 int i;
93 int ret;
94
95 ret = fbtft_request_one_gpio(par, "reset", 0, &par->gpio.reset);
96 if (ret)
97 return ret;
98 ret = fbtft_request_one_gpio(par, "dc", 0, &par->gpio.dc);
99 if (ret)
100 return ret;
101 ret = fbtft_request_one_gpio(par, "rd", 0, &par->gpio.rd);
102 if (ret)
103 return ret;
104 ret = fbtft_request_one_gpio(par, "wr", 0, &par->gpio.wr);
105 if (ret)
106 return ret;
107 ret = fbtft_request_one_gpio(par, "cs", 0, &par->gpio.cs);
108 if (ret)
109 return ret;
110 ret = fbtft_request_one_gpio(par, "latch", 0, &par->gpio.latch);
111 if (ret)
112 return ret;
113 for (i = 0; i < 16; i++) {
114 ret = fbtft_request_one_gpio(par, "db", i,
115 &par->gpio.db[i]);
116 if (ret)
117 return ret;
118 ret = fbtft_request_one_gpio(par, "led", i,
119 &par->gpio.led[i]);
120 if (ret)
121 return ret;
122 ret = fbtft_request_one_gpio(par, "aux", i,
123 &par->gpio.aux[i]);
124 if (ret)
125 return ret;
126 }
127
128 return 0;
129 }
130
fbtft_backlight_update_status(struct backlight_device * bd)131 static int fbtft_backlight_update_status(struct backlight_device *bd)
132 {
133 struct fbtft_par *par = bl_get_data(bd);
134 bool polarity = par->polarity;
135
136 fbtft_par_dbg(DEBUG_BACKLIGHT, par, "%s: polarity=%d, power=%d\n", __func__,
137 polarity, bd->props.power);
138
139 if (!backlight_is_blank(bd))
140 gpiod_set_value(par->gpio.led[0], polarity);
141 else
142 gpiod_set_value(par->gpio.led[0], !polarity);
143
144 return 0;
145 }
146
fbtft_backlight_get_brightness(struct backlight_device * bd)147 static int fbtft_backlight_get_brightness(struct backlight_device *bd)
148 {
149 return bd->props.brightness;
150 }
151
fbtft_unregister_backlight(struct fbtft_par * par)152 void fbtft_unregister_backlight(struct fbtft_par *par)
153 {
154 if (par->info->bl_dev) {
155 par->info->bl_dev->props.power = FB_BLANK_POWERDOWN;
156 backlight_update_status(par->info->bl_dev);
157 backlight_device_unregister(par->info->bl_dev);
158 par->info->bl_dev = NULL;
159 }
160 }
161 EXPORT_SYMBOL(fbtft_unregister_backlight);
162
163 static const struct backlight_ops fbtft_bl_ops = {
164 .get_brightness = fbtft_backlight_get_brightness,
165 .update_status = fbtft_backlight_update_status,
166 };
167
fbtft_register_backlight(struct fbtft_par * par)168 void fbtft_register_backlight(struct fbtft_par *par)
169 {
170 struct backlight_device *bd;
171 struct backlight_properties bl_props = { 0, };
172
173 if (!par->gpio.led[0]) {
174 fbtft_par_dbg(DEBUG_BACKLIGHT, par,
175 "%s(): led pin not set, exiting.\n", __func__);
176 return;
177 }
178
179 bl_props.type = BACKLIGHT_RAW;
180 /* Assume backlight is off, get polarity from current state of pin */
181 bl_props.power = FB_BLANK_POWERDOWN;
182 if (!gpiod_get_value(par->gpio.led[0]))
183 par->polarity = true;
184
185 bd = backlight_device_register(dev_driver_string(par->info->device),
186 par->info->device, par,
187 &fbtft_bl_ops, &bl_props);
188 if (IS_ERR(bd)) {
189 dev_err(par->info->device,
190 "cannot register backlight device (%ld)\n",
191 PTR_ERR(bd));
192 return;
193 }
194 par->info->bl_dev = bd;
195
196 if (!par->fbtftops.unregister_backlight)
197 par->fbtftops.unregister_backlight = fbtft_unregister_backlight;
198 }
199 EXPORT_SYMBOL(fbtft_register_backlight);
200
fbtft_set_addr_win(struct fbtft_par * par,int xs,int ys,int xe,int ye)201 static void fbtft_set_addr_win(struct fbtft_par *par, int xs, int ys, int xe,
202 int ye)
203 {
204 write_reg(par, MIPI_DCS_SET_COLUMN_ADDRESS,
205 (xs >> 8) & 0xFF, xs & 0xFF, (xe >> 8) & 0xFF, xe & 0xFF);
206
207 write_reg(par, MIPI_DCS_SET_PAGE_ADDRESS,
208 (ys >> 8) & 0xFF, ys & 0xFF, (ye >> 8) & 0xFF, ye & 0xFF);
209
210 write_reg(par, MIPI_DCS_WRITE_MEMORY_START);
211 }
212
fbtft_reset(struct fbtft_par * par)213 static void fbtft_reset(struct fbtft_par *par)
214 {
215 if (!par->gpio.reset)
216 return;
217
218 fbtft_par_dbg(DEBUG_RESET, par, "%s()\n", __func__);
219
220 gpiod_set_value_cansleep(par->gpio.reset, 1);
221 usleep_range(20, 40);
222 gpiod_set_value_cansleep(par->gpio.reset, 0);
223 msleep(120);
224
225 gpiod_set_value_cansleep(par->gpio.cs, 1); /* Activate chip */
226 }
227
fbtft_update_display(struct fbtft_par * par,unsigned int start_line,unsigned int end_line)228 static void fbtft_update_display(struct fbtft_par *par, unsigned int start_line,
229 unsigned int end_line)
230 {
231 size_t offset, len;
232 ktime_t ts_start, ts_end;
233 long fps, throughput;
234 bool timeit = false;
235 int ret = 0;
236
237 if (unlikely(par->debug & (DEBUG_TIME_FIRST_UPDATE |
238 DEBUG_TIME_EACH_UPDATE))) {
239 if ((par->debug & DEBUG_TIME_EACH_UPDATE) ||
240 ((par->debug & DEBUG_TIME_FIRST_UPDATE) &&
241 !par->first_update_done)) {
242 ts_start = ktime_get();
243 timeit = true;
244 }
245 }
246
247 /* Sanity checks */
248 if (start_line > end_line) {
249 dev_warn(par->info->device,
250 "%s: start_line=%u is larger than end_line=%u. Shouldn't happen, will do full display update\n",
251 __func__, start_line, end_line);
252 start_line = 0;
253 end_line = par->info->var.yres - 1;
254 }
255 if (start_line > par->info->var.yres - 1 ||
256 end_line > par->info->var.yres - 1) {
257 dev_warn(par->info->device,
258 "%s: start_line=%u or end_line=%u is larger than max=%d. Shouldn't happen, will do full display update\n",
259 __func__, start_line,
260 end_line, par->info->var.yres - 1);
261 start_line = 0;
262 end_line = par->info->var.yres - 1;
263 }
264
265 fbtft_par_dbg(DEBUG_UPDATE_DISPLAY, par, "%s(start_line=%u, end_line=%u)\n",
266 __func__, start_line, end_line);
267
268 if (par->fbtftops.set_addr_win)
269 par->fbtftops.set_addr_win(par, 0, start_line,
270 par->info->var.xres - 1, end_line);
271
272 offset = start_line * par->info->fix.line_length;
273 len = (end_line - start_line + 1) * par->info->fix.line_length;
274 ret = par->fbtftops.write_vmem(par, offset, len);
275 if (ret < 0)
276 dev_err(par->info->device,
277 "%s: write_vmem failed to update display buffer\n",
278 __func__);
279
280 if (unlikely(timeit)) {
281 ts_end = ktime_get();
282 if (!ktime_to_ns(par->update_time))
283 par->update_time = ts_start;
284
285 fps = ktime_us_delta(ts_start, par->update_time);
286 par->update_time = ts_start;
287 fps = fps ? 1000000 / fps : 0;
288
289 throughput = ktime_us_delta(ts_end, ts_start);
290 throughput = throughput ? (len * 1000) / throughput : 0;
291 throughput = throughput * 1000 / 1024;
292
293 dev_info(par->info->device,
294 "Display update: %ld kB/s, fps=%ld\n",
295 throughput, fps);
296 par->first_update_done = true;
297 }
298 }
299
fbtft_mkdirty(struct fb_info * info,int y,int height)300 static void fbtft_mkdirty(struct fb_info *info, int y, int height)
301 {
302 struct fbtft_par *par = info->par;
303 struct fb_deferred_io *fbdefio = info->fbdefio;
304
305 /* special case, needed ? */
306 if (y == -1) {
307 y = 0;
308 height = info->var.yres;
309 }
310
311 /* Mark display lines/area as dirty */
312 spin_lock(&par->dirty_lock);
313 if (y < par->dirty_lines_start)
314 par->dirty_lines_start = y;
315 if (y + height - 1 > par->dirty_lines_end)
316 par->dirty_lines_end = y + height - 1;
317 spin_unlock(&par->dirty_lock);
318
319 /* Schedule deferred_io to update display (no-op if already on queue)*/
320 schedule_delayed_work(&info->deferred_work, fbdefio->delay);
321 }
322
fbtft_deferred_io(struct fb_info * info,struct list_head * pagereflist)323 static void fbtft_deferred_io(struct fb_info *info, struct list_head *pagereflist)
324 {
325 struct fbtft_par *par = info->par;
326 unsigned int dirty_lines_start, dirty_lines_end;
327 struct fb_deferred_io_pageref *pageref;
328 unsigned int y_low = 0, y_high = 0;
329
330 spin_lock(&par->dirty_lock);
331 dirty_lines_start = par->dirty_lines_start;
332 dirty_lines_end = par->dirty_lines_end;
333 /* set display line markers as clean */
334 par->dirty_lines_start = par->info->var.yres - 1;
335 par->dirty_lines_end = 0;
336 spin_unlock(&par->dirty_lock);
337
338 /* Mark display lines as dirty */
339 list_for_each_entry(pageref, pagereflist, list) {
340 y_low = pageref->offset / info->fix.line_length;
341 y_high = (pageref->offset + PAGE_SIZE - 1) / info->fix.line_length;
342 dev_dbg(info->device,
343 "page->index=%lu y_low=%d y_high=%d\n",
344 pageref->page->index, y_low, y_high);
345 if (y_high > info->var.yres - 1)
346 y_high = info->var.yres - 1;
347 if (y_low < dirty_lines_start)
348 dirty_lines_start = y_low;
349 if (y_high > dirty_lines_end)
350 dirty_lines_end = y_high;
351 }
352
353 par->fbtftops.update_display(info->par,
354 dirty_lines_start, dirty_lines_end);
355 }
356
357 /* from pxafb.c */
chan_to_field(unsigned int chan,struct fb_bitfield * bf)358 static unsigned int chan_to_field(unsigned int chan, struct fb_bitfield *bf)
359 {
360 chan &= 0xffff;
361 chan >>= 16 - bf->length;
362 return chan << bf->offset;
363 }
364
fbtft_fb_setcolreg(unsigned int regno,unsigned int red,unsigned int green,unsigned int blue,unsigned int transp,struct fb_info * info)365 static int fbtft_fb_setcolreg(unsigned int regno, unsigned int red,
366 unsigned int green, unsigned int blue,
367 unsigned int transp, struct fb_info *info)
368 {
369 unsigned int val;
370 int ret = 1;
371
372 dev_dbg(info->dev,
373 "%s(regno=%u, red=0x%X, green=0x%X, blue=0x%X, trans=0x%X)\n",
374 __func__, regno, red, green, blue, transp);
375
376 switch (info->fix.visual) {
377 case FB_VISUAL_TRUECOLOR:
378 if (regno < 16) {
379 u32 *pal = info->pseudo_palette;
380
381 val = chan_to_field(red, &info->var.red);
382 val |= chan_to_field(green, &info->var.green);
383 val |= chan_to_field(blue, &info->var.blue);
384
385 pal[regno] = val;
386 ret = 0;
387 }
388 break;
389 }
390 return ret;
391 }
392
fbtft_fb_blank(int blank,struct fb_info * info)393 static int fbtft_fb_blank(int blank, struct fb_info *info)
394 {
395 struct fbtft_par *par = info->par;
396 int ret = -EINVAL;
397
398 dev_dbg(info->dev, "%s(blank=%d)\n",
399 __func__, blank);
400
401 if (!par->fbtftops.blank)
402 return ret;
403
404 switch (blank) {
405 case FB_BLANK_POWERDOWN:
406 case FB_BLANK_VSYNC_SUSPEND:
407 case FB_BLANK_HSYNC_SUSPEND:
408 case FB_BLANK_NORMAL:
409 ret = par->fbtftops.blank(par, true);
410 break;
411 case FB_BLANK_UNBLANK:
412 ret = par->fbtftops.blank(par, false);
413 break;
414 }
415 return ret;
416 }
417
fbtft_ops_damage_range(struct fb_info * info,off_t off,size_t len)418 static void fbtft_ops_damage_range(struct fb_info *info, off_t off, size_t len)
419 {
420 struct fbtft_par *par = info->par;
421
422 /* TODO: only mark changed area update all for now */
423 par->fbtftops.mkdirty(info, -1, 0);
424 }
425
fbtft_ops_damage_area(struct fb_info * info,u32 x,u32 y,u32 width,u32 height)426 static void fbtft_ops_damage_area(struct fb_info *info, u32 x, u32 y, u32 width, u32 height)
427 {
428 struct fbtft_par *par = info->par;
429
430 par->fbtftops.mkdirty(info, y, height);
431 }
432
433 FB_GEN_DEFAULT_DEFERRED_SYSMEM_OPS(fbtft_ops,
434 fbtft_ops_damage_range,
435 fbtft_ops_damage_area)
436
437 static const struct fb_ops fbtft_ops = {
438 .owner = THIS_MODULE,
439 FB_DEFAULT_DEFERRED_OPS(fbtft_ops),
440 .fb_setcolreg = fbtft_fb_setcolreg,
441 .fb_blank = fbtft_fb_blank,
442 };
443
fbtft_merge_fbtftops(struct fbtft_ops * dst,struct fbtft_ops * src)444 static void fbtft_merge_fbtftops(struct fbtft_ops *dst, struct fbtft_ops *src)
445 {
446 if (src->write)
447 dst->write = src->write;
448 if (src->read)
449 dst->read = src->read;
450 if (src->write_vmem)
451 dst->write_vmem = src->write_vmem;
452 if (src->write_register)
453 dst->write_register = src->write_register;
454 if (src->set_addr_win)
455 dst->set_addr_win = src->set_addr_win;
456 if (src->reset)
457 dst->reset = src->reset;
458 if (src->mkdirty)
459 dst->mkdirty = src->mkdirty;
460 if (src->update_display)
461 dst->update_display = src->update_display;
462 if (src->init_display)
463 dst->init_display = src->init_display;
464 if (src->blank)
465 dst->blank = src->blank;
466 if (src->request_gpios_match)
467 dst->request_gpios_match = src->request_gpios_match;
468 if (src->request_gpios)
469 dst->request_gpios = src->request_gpios;
470 if (src->verify_gpios)
471 dst->verify_gpios = src->verify_gpios;
472 if (src->register_backlight)
473 dst->register_backlight = src->register_backlight;
474 if (src->unregister_backlight)
475 dst->unregister_backlight = src->unregister_backlight;
476 if (src->set_var)
477 dst->set_var = src->set_var;
478 if (src->set_gamma)
479 dst->set_gamma = src->set_gamma;
480 }
481
482 /**
483 * fbtft_framebuffer_alloc - creates a new frame buffer info structure
484 *
485 * @display: pointer to structure describing the display
486 * @dev: pointer to the device for this fb, this can be NULL
487 * @pdata: platform data for the display in use
488 *
489 * Creates a new frame buffer info structure.
490 *
491 * Also creates and populates the following structures:
492 * info->fbdefio
493 * info->pseudo_palette
494 * par->fbtftops
495 * par->txbuf
496 *
497 * Returns the new structure, or NULL if an error occurred.
498 *
499 */
fbtft_framebuffer_alloc(struct fbtft_display * display,struct device * dev,struct fbtft_platform_data * pdata)500 struct fb_info *fbtft_framebuffer_alloc(struct fbtft_display *display,
501 struct device *dev,
502 struct fbtft_platform_data *pdata)
503 {
504 struct fb_info *info;
505 struct fbtft_par *par;
506 struct fb_deferred_io *fbdefio = NULL;
507 u8 *vmem = NULL;
508 void *txbuf = NULL;
509 void *buf = NULL;
510 unsigned int width;
511 unsigned int height;
512 int txbuflen = display->txbuflen;
513 unsigned int bpp = display->bpp;
514 unsigned int fps = display->fps;
515 int vmem_size;
516 const s16 *init_sequence = display->init_sequence;
517 char *gamma = display->gamma;
518 u32 *gamma_curves = NULL;
519
520 /* sanity check */
521 if (display->gamma_num * display->gamma_len >
522 FBTFT_GAMMA_MAX_VALUES_TOTAL) {
523 dev_err(dev, "FBTFT_GAMMA_MAX_VALUES_TOTAL=%d is exceeded\n",
524 FBTFT_GAMMA_MAX_VALUES_TOTAL);
525 return NULL;
526 }
527
528 /* defaults */
529 if (!fps)
530 fps = 20;
531 if (!bpp)
532 bpp = 16;
533
534 if (!pdata) {
535 dev_err(dev, "platform data is missing\n");
536 return NULL;
537 }
538
539 /* override driver values? */
540 if (pdata->fps)
541 fps = pdata->fps;
542 if (pdata->txbuflen)
543 txbuflen = pdata->txbuflen;
544 if (pdata->display.init_sequence)
545 init_sequence = pdata->display.init_sequence;
546 if (pdata->gamma)
547 gamma = pdata->gamma;
548 if (pdata->display.debug)
549 display->debug = pdata->display.debug;
550 if (pdata->display.backlight)
551 display->backlight = pdata->display.backlight;
552 if (pdata->display.width)
553 display->width = pdata->display.width;
554 if (pdata->display.height)
555 display->height = pdata->display.height;
556 if (pdata->display.buswidth)
557 display->buswidth = pdata->display.buswidth;
558 if (pdata->display.regwidth)
559 display->regwidth = pdata->display.regwidth;
560
561 display->debug |= debug;
562 fbtft_expand_debug_value(&display->debug);
563
564 switch (pdata->rotate) {
565 case 90:
566 case 270:
567 width = display->height;
568 height = display->width;
569 break;
570 default:
571 width = display->width;
572 height = display->height;
573 }
574
575 vmem_size = display->width * display->height * bpp / 8;
576 vmem = vzalloc(vmem_size);
577 if (!vmem)
578 goto alloc_fail;
579
580 fbdefio = devm_kzalloc(dev, sizeof(struct fb_deferred_io), GFP_KERNEL);
581 if (!fbdefio)
582 goto alloc_fail;
583
584 buf = devm_kzalloc(dev, 128, GFP_KERNEL);
585 if (!buf)
586 goto alloc_fail;
587
588 if (display->gamma_num && display->gamma_len) {
589 gamma_curves = devm_kcalloc(dev,
590 display->gamma_num *
591 display->gamma_len,
592 sizeof(gamma_curves[0]),
593 GFP_KERNEL);
594 if (!gamma_curves)
595 goto alloc_fail;
596 }
597
598 info = framebuffer_alloc(sizeof(struct fbtft_par), dev);
599 if (!info)
600 goto alloc_fail;
601
602 info->screen_buffer = vmem;
603 info->fbops = &fbtft_ops;
604 info->fbdefio = fbdefio;
605
606 fbdefio->delay = HZ / fps;
607 fbdefio->sort_pagereflist = true;
608 fbdefio->deferred_io = fbtft_deferred_io;
609
610 snprintf(info->fix.id, sizeof(info->fix.id), "%s", dev->driver->name);
611 info->fix.type = FB_TYPE_PACKED_PIXELS;
612 info->fix.visual = FB_VISUAL_TRUECOLOR;
613 info->fix.xpanstep = 0;
614 info->fix.ypanstep = 0;
615 info->fix.ywrapstep = 0;
616 info->fix.line_length = width * bpp / 8;
617 info->fix.accel = FB_ACCEL_NONE;
618 info->fix.smem_len = vmem_size;
619 fb_deferred_io_init(info);
620
621 info->var.rotate = pdata->rotate;
622 info->var.xres = width;
623 info->var.yres = height;
624 info->var.xres_virtual = info->var.xres;
625 info->var.yres_virtual = info->var.yres;
626 info->var.bits_per_pixel = bpp;
627 info->var.nonstd = 1;
628
629 /* RGB565 */
630 info->var.red.offset = 11;
631 info->var.red.length = 5;
632 info->var.green.offset = 5;
633 info->var.green.length = 6;
634 info->var.blue.offset = 0;
635 info->var.blue.length = 5;
636 info->var.transp.offset = 0;
637 info->var.transp.length = 0;
638
639 info->flags = FBINFO_VIRTFB;
640
641 par = info->par;
642 par->info = info;
643 par->pdata = pdata;
644 par->debug = display->debug;
645 par->buf = buf;
646 spin_lock_init(&par->dirty_lock);
647 par->bgr = pdata->bgr;
648 par->startbyte = pdata->startbyte;
649 par->init_sequence = init_sequence;
650 par->gamma.curves = gamma_curves;
651 par->gamma.num_curves = display->gamma_num;
652 par->gamma.num_values = display->gamma_len;
653 mutex_init(&par->gamma.lock);
654 info->pseudo_palette = par->pseudo_palette;
655
656 if (par->gamma.curves && gamma) {
657 if (fbtft_gamma_parse_str(par, par->gamma.curves, gamma,
658 strlen(gamma)))
659 goto release_framebuf;
660 }
661
662 /* Transmit buffer */
663 if (txbuflen == -1)
664 txbuflen = vmem_size + 2; /* add in case startbyte is used */
665 if (txbuflen >= vmem_size + 2)
666 txbuflen = 0;
667
668 #ifdef __LITTLE_ENDIAN
669 if ((!txbuflen) && (bpp > 8))
670 txbuflen = PAGE_SIZE; /* need buffer for byteswapping */
671 #endif
672
673 if (txbuflen > 0) {
674 txbuf = devm_kzalloc(par->info->device, txbuflen, GFP_KERNEL);
675 if (!txbuf)
676 goto release_framebuf;
677 par->txbuf.buf = txbuf;
678 par->txbuf.len = txbuflen;
679 }
680
681 /* default fbtft operations */
682 par->fbtftops.write = fbtft_write_spi;
683 par->fbtftops.read = fbtft_read_spi;
684 par->fbtftops.write_vmem = fbtft_write_vmem16_bus8;
685 par->fbtftops.write_register = fbtft_write_reg8_bus8;
686 par->fbtftops.set_addr_win = fbtft_set_addr_win;
687 par->fbtftops.reset = fbtft_reset;
688 par->fbtftops.mkdirty = fbtft_mkdirty;
689 par->fbtftops.update_display = fbtft_update_display;
690 if (display->backlight)
691 par->fbtftops.register_backlight = fbtft_register_backlight;
692
693 /* use driver provided functions */
694 fbtft_merge_fbtftops(&par->fbtftops, &display->fbtftops);
695
696 return info;
697
698 release_framebuf:
699 framebuffer_release(info);
700
701 alloc_fail:
702 vfree(vmem);
703
704 return NULL;
705 }
706 EXPORT_SYMBOL(fbtft_framebuffer_alloc);
707
708 /**
709 * fbtft_framebuffer_release - frees up all memory used by the framebuffer
710 *
711 * @info: frame buffer info structure
712 *
713 */
fbtft_framebuffer_release(struct fb_info * info)714 void fbtft_framebuffer_release(struct fb_info *info)
715 {
716 fb_deferred_io_cleanup(info);
717 vfree(info->screen_buffer);
718 framebuffer_release(info);
719 }
720 EXPORT_SYMBOL(fbtft_framebuffer_release);
721
722 /**
723 * fbtft_register_framebuffer - registers a tft frame buffer device
724 * @fb_info: frame buffer info structure
725 *
726 * Sets SPI driverdata if needed
727 * Requests needed gpios.
728 * Initializes display
729 * Updates display.
730 * Registers a frame buffer device @fb_info.
731 *
732 * Returns negative errno on error, or zero for success.
733 *
734 */
fbtft_register_framebuffer(struct fb_info * fb_info)735 int fbtft_register_framebuffer(struct fb_info *fb_info)
736 {
737 int ret;
738 char text1[50] = "";
739 char text2[50] = "";
740 struct fbtft_par *par = fb_info->par;
741 struct spi_device *spi = par->spi;
742
743 /* sanity checks */
744 if (!par->fbtftops.init_display) {
745 dev_err(fb_info->device, "missing fbtftops.init_display()\n");
746 return -EINVAL;
747 }
748
749 if (spi)
750 spi_set_drvdata(spi, fb_info);
751 if (par->pdev)
752 platform_set_drvdata(par->pdev, fb_info);
753
754 ret = par->fbtftops.request_gpios(par);
755 if (ret < 0)
756 goto reg_fail;
757
758 if (par->fbtftops.verify_gpios) {
759 ret = par->fbtftops.verify_gpios(par);
760 if (ret < 0)
761 goto reg_fail;
762 }
763
764 ret = par->fbtftops.init_display(par);
765 if (ret < 0)
766 goto reg_fail;
767 if (par->fbtftops.set_var) {
768 ret = par->fbtftops.set_var(par);
769 if (ret < 0)
770 goto reg_fail;
771 }
772
773 /* update the entire display */
774 par->fbtftops.update_display(par, 0, par->info->var.yres - 1);
775
776 if (par->fbtftops.set_gamma && par->gamma.curves) {
777 ret = par->fbtftops.set_gamma(par, par->gamma.curves);
778 if (ret)
779 goto reg_fail;
780 }
781
782 if (par->fbtftops.register_backlight)
783 par->fbtftops.register_backlight(par);
784
785 ret = register_framebuffer(fb_info);
786 if (ret < 0)
787 goto reg_fail;
788
789 fbtft_sysfs_init(par);
790
791 if (par->txbuf.buf && par->txbuf.len >= 1024)
792 sprintf(text1, ", %zu KiB buffer memory", par->txbuf.len >> 10);
793 if (spi)
794 sprintf(text2, ", spi%d.%d at %d MHz", spi->controller->bus_num,
795 spi_get_chipselect(spi, 0), spi->max_speed_hz / 1000000);
796 dev_info(fb_info->dev,
797 "%s frame buffer, %dx%d, %d KiB video memory%s, fps=%lu%s\n",
798 fb_info->fix.id, fb_info->var.xres, fb_info->var.yres,
799 fb_info->fix.smem_len >> 10, text1,
800 HZ / fb_info->fbdefio->delay, text2);
801
802 /* Turn on backlight if available */
803 if (fb_info->bl_dev) {
804 fb_info->bl_dev->props.power = FB_BLANK_UNBLANK;
805 fb_info->bl_dev->ops->update_status(fb_info->bl_dev);
806 }
807
808 return 0;
809
810 reg_fail:
811 if (par->fbtftops.unregister_backlight)
812 par->fbtftops.unregister_backlight(par);
813
814 return ret;
815 }
816 EXPORT_SYMBOL(fbtft_register_framebuffer);
817
818 /**
819 * fbtft_unregister_framebuffer - releases a tft frame buffer device
820 * @fb_info: frame buffer info structure
821 *
822 * Frees SPI driverdata if needed
823 * Frees gpios.
824 * Unregisters frame buffer device.
825 *
826 */
fbtft_unregister_framebuffer(struct fb_info * fb_info)827 int fbtft_unregister_framebuffer(struct fb_info *fb_info)
828 {
829 struct fbtft_par *par = fb_info->par;
830
831 if (par->fbtftops.unregister_backlight)
832 par->fbtftops.unregister_backlight(par);
833 fbtft_sysfs_exit(par);
834 unregister_framebuffer(fb_info);
835
836 return 0;
837 }
838 EXPORT_SYMBOL(fbtft_unregister_framebuffer);
839
840 /**
841 * fbtft_init_display_from_property() - Device Tree init_display() function
842 * @par: Driver data
843 *
844 * Return: 0 if successful, negative if error
845 */
fbtft_init_display_from_property(struct fbtft_par * par)846 static int fbtft_init_display_from_property(struct fbtft_par *par)
847 {
848 struct device *dev = par->info->device;
849 int buf[64], count, index, i, j, ret;
850 u32 *values;
851 u32 val;
852
853 count = device_property_count_u32(dev, "init");
854 if (count < 0)
855 return count;
856 if (count == 0)
857 return -EINVAL;
858
859 values = kmalloc_array(count + 1, sizeof(*values), GFP_KERNEL);
860 if (!values)
861 return -ENOMEM;
862
863 ret = device_property_read_u32_array(dev, "init", values, count);
864 if (ret)
865 goto out_free;
866
867 par->fbtftops.reset(par);
868
869 index = -1;
870 val = values[++index];
871
872 while (index < count) {
873 if (val & FBTFT_OF_INIT_CMD) {
874 val &= 0xFFFF;
875 i = 0;
876 while ((index < count) && !(val & 0xFFFF0000)) {
877 if (i > 63) {
878 dev_err(dev,
879 "%s: Maximum register values exceeded\n",
880 __func__);
881 ret = -EINVAL;
882 goto out_free;
883 }
884 buf[i++] = val;
885 val = values[++index];
886 }
887 /* make debug message */
888 fbtft_par_dbg(DEBUG_INIT_DISPLAY, par,
889 "init: write_register:\n");
890 for (j = 0; j < i; j++)
891 fbtft_par_dbg(DEBUG_INIT_DISPLAY, par,
892 "buf[%d] = %02X\n", j, buf[j]);
893
894 par->fbtftops.write_register(par, i,
895 buf[0], buf[1], buf[2], buf[3],
896 buf[4], buf[5], buf[6], buf[7],
897 buf[8], buf[9], buf[10], buf[11],
898 buf[12], buf[13], buf[14], buf[15],
899 buf[16], buf[17], buf[18], buf[19],
900 buf[20], buf[21], buf[22], buf[23],
901 buf[24], buf[25], buf[26], buf[27],
902 buf[28], buf[29], buf[30], buf[31],
903 buf[32], buf[33], buf[34], buf[35],
904 buf[36], buf[37], buf[38], buf[39],
905 buf[40], buf[41], buf[42], buf[43],
906 buf[44], buf[45], buf[46], buf[47],
907 buf[48], buf[49], buf[50], buf[51],
908 buf[52], buf[53], buf[54], buf[55],
909 buf[56], buf[57], buf[58], buf[59],
910 buf[60], buf[61], buf[62], buf[63]);
911 } else if (val & FBTFT_OF_INIT_DELAY) {
912 fbtft_par_dbg(DEBUG_INIT_DISPLAY, par,
913 "init: msleep(%u)\n", val & 0xFFFF);
914 msleep(val & 0xFFFF);
915 val = values[++index];
916 } else {
917 dev_err(dev, "illegal init value 0x%X\n", val);
918 ret = -EINVAL;
919 goto out_free;
920 }
921 }
922
923 out_free:
924 kfree(values);
925 return ret;
926 }
927
928 /**
929 * fbtft_init_display() - Generic init_display() function
930 * @par: Driver data
931 *
932 * Uses par->init_sequence to do the initialization
933 *
934 * Return: 0 if successful, negative if error
935 */
fbtft_init_display(struct fbtft_par * par)936 int fbtft_init_display(struct fbtft_par *par)
937 {
938 int buf[64];
939 int i;
940 int j;
941
942 /* sanity check */
943 if (!par->init_sequence) {
944 dev_err(par->info->device,
945 "error: init_sequence is not set\n");
946 return -EINVAL;
947 }
948
949 /* make sure stop marker exists */
950 for (i = 0; i < FBTFT_MAX_INIT_SEQUENCE; i++) {
951 if (par->init_sequence[i] == -3)
952 break;
953 }
954
955 if (i == FBTFT_MAX_INIT_SEQUENCE) {
956 dev_err(par->info->device,
957 "missing stop marker at end of init sequence\n");
958 return -EINVAL;
959 }
960
961 par->fbtftops.reset(par);
962
963 i = 0;
964 while (i < FBTFT_MAX_INIT_SEQUENCE) {
965 if (par->init_sequence[i] == -3) {
966 /* done */
967 return 0;
968 }
969 if (par->init_sequence[i] >= 0) {
970 dev_err(par->info->device,
971 "missing delimiter at position %d\n", i);
972 return -EINVAL;
973 }
974 if (par->init_sequence[i + 1] < 0) {
975 dev_err(par->info->device,
976 "missing value after delimiter %d at position %d\n",
977 par->init_sequence[i], i);
978 return -EINVAL;
979 }
980 switch (par->init_sequence[i]) {
981 case -1:
982 i++;
983
984 /* make debug message */
985 for (j = 0; par->init_sequence[i + 1 + j] >= 0; j++)
986 ;
987
988 fbtft_par_dbg_hex(DEBUG_INIT_DISPLAY, par, par->info->device,
989 s16, &par->init_sequence[i + 1], j,
990 "init: write(0x%02X)", par->init_sequence[i]);
991
992 /* Write */
993 j = 0;
994 while (par->init_sequence[i] >= 0) {
995 if (j > 63) {
996 dev_err(par->info->device,
997 "%s: Maximum register values exceeded\n",
998 __func__);
999 return -EINVAL;
1000 }
1001 buf[j++] = par->init_sequence[i++];
1002 }
1003 par->fbtftops.write_register(par, j,
1004 buf[0], buf[1], buf[2], buf[3],
1005 buf[4], buf[5], buf[6], buf[7],
1006 buf[8], buf[9], buf[10], buf[11],
1007 buf[12], buf[13], buf[14], buf[15],
1008 buf[16], buf[17], buf[18], buf[19],
1009 buf[20], buf[21], buf[22], buf[23],
1010 buf[24], buf[25], buf[26], buf[27],
1011 buf[28], buf[29], buf[30], buf[31],
1012 buf[32], buf[33], buf[34], buf[35],
1013 buf[36], buf[37], buf[38], buf[39],
1014 buf[40], buf[41], buf[42], buf[43],
1015 buf[44], buf[45], buf[46], buf[47],
1016 buf[48], buf[49], buf[50], buf[51],
1017 buf[52], buf[53], buf[54], buf[55],
1018 buf[56], buf[57], buf[58], buf[59],
1019 buf[60], buf[61], buf[62], buf[63]);
1020 break;
1021 case -2:
1022 i++;
1023 fbtft_par_dbg(DEBUG_INIT_DISPLAY, par,
1024 "init: mdelay(%d)\n",
1025 par->init_sequence[i]);
1026 mdelay(par->init_sequence[i++]);
1027 break;
1028 default:
1029 dev_err(par->info->device,
1030 "unknown delimiter %d at position %d\n",
1031 par->init_sequence[i], i);
1032 return -EINVAL;
1033 }
1034 }
1035
1036 dev_err(par->info->device,
1037 "%s: something is wrong. Shouldn't get here.\n", __func__);
1038 return -EINVAL;
1039 }
1040 EXPORT_SYMBOL(fbtft_init_display);
1041
1042 /**
1043 * fbtft_verify_gpios() - Generic verify_gpios() function
1044 * @par: Driver data
1045 *
1046 * Uses @spi, @pdev and @buswidth to determine which GPIOs is needed
1047 *
1048 * Return: 0 if successful, negative if error
1049 */
fbtft_verify_gpios(struct fbtft_par * par)1050 static int fbtft_verify_gpios(struct fbtft_par *par)
1051 {
1052 struct fbtft_platform_data *pdata = par->pdata;
1053 int i;
1054
1055 fbtft_par_dbg(DEBUG_VERIFY_GPIOS, par, "%s()\n", __func__);
1056
1057 if (pdata->display.buswidth != 9 && par->startbyte == 0 &&
1058 !par->gpio.dc) {
1059 dev_err(par->info->device,
1060 "Missing info about 'dc' gpio. Aborting.\n");
1061 return -EINVAL;
1062 }
1063
1064 if (!par->pdev)
1065 return 0;
1066
1067 if (!par->gpio.wr) {
1068 dev_err(par->info->device, "Missing 'wr' gpio. Aborting.\n");
1069 return -EINVAL;
1070 }
1071 for (i = 0; i < pdata->display.buswidth; i++) {
1072 if (!par->gpio.db[i]) {
1073 dev_err(par->info->device,
1074 "Missing 'db%02d' gpio. Aborting.\n", i);
1075 return -EINVAL;
1076 }
1077 }
1078
1079 return 0;
1080 }
1081
1082 /* returns 0 if the property is not present */
fbtft_property_value(struct device * dev,const char * propname)1083 static u32 fbtft_property_value(struct device *dev, const char *propname)
1084 {
1085 int ret;
1086 u32 val = 0;
1087
1088 ret = device_property_read_u32(dev, propname, &val);
1089 if (ret == 0)
1090 dev_info(dev, "%s: %s = %u\n", __func__, propname, val);
1091
1092 return val;
1093 }
1094
fbtft_properties_read(struct device * dev)1095 static struct fbtft_platform_data *fbtft_properties_read(struct device *dev)
1096 {
1097 struct fbtft_platform_data *pdata;
1098
1099 if (!dev_fwnode(dev)) {
1100 dev_err(dev, "Missing platform data or properties\n");
1101 return ERR_PTR(-EINVAL);
1102 }
1103
1104 pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
1105 if (!pdata)
1106 return ERR_PTR(-ENOMEM);
1107
1108 pdata->display.width = fbtft_property_value(dev, "width");
1109 pdata->display.height = fbtft_property_value(dev, "height");
1110 pdata->display.regwidth = fbtft_property_value(dev, "regwidth");
1111 pdata->display.buswidth = fbtft_property_value(dev, "buswidth");
1112 pdata->display.backlight = fbtft_property_value(dev, "backlight");
1113 pdata->display.bpp = fbtft_property_value(dev, "bpp");
1114 pdata->display.debug = fbtft_property_value(dev, "debug");
1115 pdata->rotate = fbtft_property_value(dev, "rotate");
1116 pdata->bgr = device_property_read_bool(dev, "bgr");
1117 pdata->fps = fbtft_property_value(dev, "fps");
1118 pdata->txbuflen = fbtft_property_value(dev, "txbuflen");
1119 pdata->startbyte = fbtft_property_value(dev, "startbyte");
1120 device_property_read_string(dev, "gamma", (const char **)&pdata->gamma);
1121
1122 if (device_property_present(dev, "led-gpios"))
1123 pdata->display.backlight = 1;
1124 if (device_property_present(dev, "init"))
1125 pdata->display.fbtftops.init_display =
1126 fbtft_init_display_from_property;
1127
1128 pdata->display.fbtftops.request_gpios = fbtft_request_gpios;
1129
1130 return pdata;
1131 }
1132
1133 /**
1134 * fbtft_probe_common() - Generic device probe() helper function
1135 * @display: Display properties
1136 * @sdev: SPI device
1137 * @pdev: Platform device
1138 *
1139 * Allocates, initializes and registers a framebuffer
1140 *
1141 * Either @sdev or @pdev should be NULL
1142 *
1143 * Return: 0 if successful, negative if error
1144 */
fbtft_probe_common(struct fbtft_display * display,struct spi_device * sdev,struct platform_device * pdev)1145 int fbtft_probe_common(struct fbtft_display *display,
1146 struct spi_device *sdev,
1147 struct platform_device *pdev)
1148 {
1149 struct device *dev;
1150 struct fb_info *info;
1151 struct fbtft_par *par;
1152 struct fbtft_platform_data *pdata;
1153 int ret;
1154
1155 if (sdev)
1156 dev = &sdev->dev;
1157 else
1158 dev = &pdev->dev;
1159
1160 if (unlikely(display->debug & DEBUG_DRIVER_INIT_FUNCTIONS))
1161 dev_info(dev, "%s()\n", __func__);
1162
1163 pdata = dev->platform_data;
1164 if (!pdata) {
1165 pdata = fbtft_properties_read(dev);
1166 if (IS_ERR(pdata))
1167 return PTR_ERR(pdata);
1168 }
1169
1170 info = fbtft_framebuffer_alloc(display, dev, pdata);
1171 if (!info)
1172 return -ENOMEM;
1173
1174 par = info->par;
1175 par->spi = sdev;
1176 par->pdev = pdev;
1177
1178 if (display->buswidth == 0) {
1179 dev_err(dev, "buswidth is not set\n");
1180 return -EINVAL;
1181 }
1182
1183 /* write register functions */
1184 if (display->regwidth == 8 && display->buswidth == 8)
1185 par->fbtftops.write_register = fbtft_write_reg8_bus8;
1186 else if (display->regwidth == 8 && display->buswidth == 9 && par->spi)
1187 par->fbtftops.write_register = fbtft_write_reg8_bus9;
1188 else if (display->regwidth == 16 && display->buswidth == 8)
1189 par->fbtftops.write_register = fbtft_write_reg16_bus8;
1190 else if (display->regwidth == 16 && display->buswidth == 16)
1191 par->fbtftops.write_register = fbtft_write_reg16_bus16;
1192 else
1193 dev_warn(dev,
1194 "no default functions for regwidth=%d and buswidth=%d\n",
1195 display->regwidth, display->buswidth);
1196
1197 /* write_vmem() functions */
1198 if (display->buswidth == 8)
1199 par->fbtftops.write_vmem = fbtft_write_vmem16_bus8;
1200 else if (display->buswidth == 9)
1201 par->fbtftops.write_vmem = fbtft_write_vmem16_bus9;
1202 else if (display->buswidth == 16)
1203 par->fbtftops.write_vmem = fbtft_write_vmem16_bus16;
1204
1205 /* GPIO write() functions */
1206 if (par->pdev) {
1207 if (display->buswidth == 8)
1208 par->fbtftops.write = fbtft_write_gpio8_wr;
1209 else if (display->buswidth == 16)
1210 par->fbtftops.write = fbtft_write_gpio16_wr;
1211 }
1212
1213 /* 9-bit SPI setup */
1214 if (par->spi && display->buswidth == 9) {
1215 if (par->spi->controller->bits_per_word_mask & SPI_BPW_MASK(9)) {
1216 par->spi->bits_per_word = 9;
1217 } else {
1218 dev_warn(&par->spi->dev,
1219 "9-bit SPI not available, emulating using 8-bit.\n");
1220 /* allocate buffer with room for dc bits */
1221 par->extra = devm_kzalloc(par->info->device,
1222 par->txbuf.len +
1223 (par->txbuf.len / 8) + 8,
1224 GFP_KERNEL);
1225 if (!par->extra) {
1226 ret = -ENOMEM;
1227 goto out_release;
1228 }
1229 par->fbtftops.write = fbtft_write_spi_emulate_9;
1230 }
1231 }
1232
1233 if (!par->fbtftops.verify_gpios)
1234 par->fbtftops.verify_gpios = fbtft_verify_gpios;
1235
1236 /* make sure we still use the driver provided functions */
1237 fbtft_merge_fbtftops(&par->fbtftops, &display->fbtftops);
1238
1239 /* use init_sequence if provided */
1240 if (par->init_sequence)
1241 par->fbtftops.init_display = fbtft_init_display;
1242
1243 /* use platform_data provided functions above all */
1244 fbtft_merge_fbtftops(&par->fbtftops, &pdata->display.fbtftops);
1245
1246 ret = fbtft_register_framebuffer(info);
1247 if (ret < 0)
1248 goto out_release;
1249
1250 return 0;
1251
1252 out_release:
1253 fbtft_framebuffer_release(info);
1254
1255 return ret;
1256 }
1257 EXPORT_SYMBOL(fbtft_probe_common);
1258
1259 /**
1260 * fbtft_remove_common() - Generic device remove() helper function
1261 * @dev: Device
1262 * @info: Framebuffer
1263 *
1264 * Unregisters and releases the framebuffer
1265 */
fbtft_remove_common(struct device * dev,struct fb_info * info)1266 void fbtft_remove_common(struct device *dev, struct fb_info *info)
1267 {
1268 struct fbtft_par *par;
1269
1270 par = info->par;
1271 if (par)
1272 fbtft_par_dbg(DEBUG_DRIVER_INIT_FUNCTIONS, par,
1273 "%s()\n", __func__);
1274 fbtft_unregister_framebuffer(info);
1275 fbtft_framebuffer_release(info);
1276 }
1277 EXPORT_SYMBOL(fbtft_remove_common);
1278
1279 MODULE_LICENSE("GPL");
1280