1 /*
2 * linux/drivers/video/vt8500lcdfb.c
3 *
4 * Copyright (C) 2010 Alexey Charkov <alchark@gmail.com>
5 *
6 * Based on skeletonfb.c and pxafb.c
7 *
8 * This software is licensed under the terms of the GNU General Public
9 * License version 2, as published by the Free Software Foundation, and
10 * may be copied, distributed, and modified under those terms.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 */
17
18 #include <linux/delay.h>
19 #include <linux/dma-mapping.h>
20 #include <linux/errno.h>
21 #include <linux/fb.h>
22 #include <linux/init.h>
23 #include <linux/interrupt.h>
24 #include <linux/io.h>
25 #include <linux/kernel.h>
26 #include <linux/mm.h>
27 #include <linux/module.h>
28 #include <linux/platform_device.h>
29 #include <linux/slab.h>
30 #include <linux/string.h>
31 #include <linux/wait.h>
32 #include <video/of_display_timing.h>
33
34 #include "vt8500lcdfb.h"
35 #include "wmt_ge_rops.h"
36
37 #ifdef CONFIG_OF
38 #include <linux/of.h>
39 #include <linux/of_fdt.h>
40 #include <linux/memblock.h>
41 #endif
42
43
44 #define to_vt8500lcd_info(__info) container_of(__info, \
45 struct vt8500lcd_info, fb)
46
vt8500lcd_set_par(struct fb_info * info)47 static int vt8500lcd_set_par(struct fb_info *info)
48 {
49 struct vt8500lcd_info *fbi = to_vt8500lcd_info(info);
50 int reg_bpp = 5; /* 16bpp */
51 int i;
52 unsigned long control0;
53
54 if (!fbi)
55 return -EINVAL;
56
57 if (info->var.bits_per_pixel <= 8) {
58 /* palettized */
59 info->var.red.offset = 0;
60 info->var.red.length = info->var.bits_per_pixel;
61 info->var.red.msb_right = 0;
62
63 info->var.green.offset = 0;
64 info->var.green.length = info->var.bits_per_pixel;
65 info->var.green.msb_right = 0;
66
67 info->var.blue.offset = 0;
68 info->var.blue.length = info->var.bits_per_pixel;
69 info->var.blue.msb_right = 0;
70
71 info->var.transp.offset = 0;
72 info->var.transp.length = 0;
73 info->var.transp.msb_right = 0;
74
75 info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
76 info->fix.line_length = info->var.xres_virtual /
77 (8/info->var.bits_per_pixel);
78 } else {
79 /* non-palettized */
80 info->var.transp.offset = 0;
81 info->var.transp.length = 0;
82 info->var.transp.msb_right = 0;
83
84 if (info->var.bits_per_pixel == 16) {
85 /* RGB565 */
86 info->var.red.offset = 11;
87 info->var.red.length = 5;
88 info->var.red.msb_right = 0;
89 info->var.green.offset = 5;
90 info->var.green.length = 6;
91 info->var.green.msb_right = 0;
92 info->var.blue.offset = 0;
93 info->var.blue.length = 5;
94 info->var.blue.msb_right = 0;
95 } else {
96 /* Equal depths per channel */
97 info->var.red.offset = info->var.bits_per_pixel
98 * 2 / 3;
99 info->var.red.length = info->var.bits_per_pixel / 3;
100 info->var.red.msb_right = 0;
101 info->var.green.offset = info->var.bits_per_pixel / 3;
102 info->var.green.length = info->var.bits_per_pixel / 3;
103 info->var.green.msb_right = 0;
104 info->var.blue.offset = 0;
105 info->var.blue.length = info->var.bits_per_pixel / 3;
106 info->var.blue.msb_right = 0;
107 }
108
109 info->fix.visual = FB_VISUAL_TRUECOLOR;
110 info->fix.line_length = info->var.bits_per_pixel > 16 ?
111 info->var.xres_virtual << 2 :
112 info->var.xres_virtual << 1;
113 }
114
115 for (i = 0; i < 8; i++) {
116 if (bpp_values[i] == info->var.bits_per_pixel) {
117 reg_bpp = i;
118 continue;
119 }
120 }
121
122 control0 = readl(fbi->regbase) & ~0xf;
123 writel(0, fbi->regbase);
124 while (readl(fbi->regbase + 0x38) & 0x10)
125 /* wait */;
126 writel((((info->var.hsync_len - 1) & 0x3f) << 26)
127 | ((info->var.left_margin & 0xff) << 18)
128 | (((info->var.xres - 1) & 0x3ff) << 8)
129 | (info->var.right_margin & 0xff), fbi->regbase + 0x4);
130 writel((((info->var.vsync_len - 1) & 0x3f) << 26)
131 | ((info->var.upper_margin & 0xff) << 18)
132 | (((info->var.yres - 1) & 0x3ff) << 8)
133 | (info->var.lower_margin & 0xff), fbi->regbase + 0x8);
134 writel((((info->var.yres - 1) & 0x400) << 2)
135 | ((info->var.xres - 1) & 0x400), fbi->regbase + 0x10);
136 writel(0x80000000, fbi->regbase + 0x20);
137 writel(control0 | (reg_bpp << 1) | 0x100, fbi->regbase);
138
139 return 0;
140 }
141
chan_to_field(u_int chan,struct fb_bitfield * bf)142 static inline u_int chan_to_field(u_int chan, struct fb_bitfield *bf)
143 {
144 chan &= 0xffff;
145 chan >>= 16 - bf->length;
146 return chan << bf->offset;
147 }
148
vt8500lcd_setcolreg(unsigned regno,unsigned red,unsigned green,unsigned blue,unsigned transp,struct fb_info * info)149 static int vt8500lcd_setcolreg(unsigned regno, unsigned red, unsigned green,
150 unsigned blue, unsigned transp,
151 struct fb_info *info) {
152 struct vt8500lcd_info *fbi = to_vt8500lcd_info(info);
153 int ret = 1;
154 unsigned int val;
155 if (regno >= 256)
156 return -EINVAL;
157
158 if (info->var.grayscale)
159 red = green = blue =
160 (19595 * red + 38470 * green + 7471 * blue) >> 16;
161
162 switch (fbi->fb.fix.visual) {
163 case FB_VISUAL_TRUECOLOR:
164 if (regno < 16) {
165 u32 *pal = fbi->fb.pseudo_palette;
166
167 val = chan_to_field(red, &fbi->fb.var.red);
168 val |= chan_to_field(green, &fbi->fb.var.green);
169 val |= chan_to_field(blue, &fbi->fb.var.blue);
170
171 pal[regno] = val;
172 ret = 0;
173 }
174 break;
175
176 case FB_VISUAL_STATIC_PSEUDOCOLOR:
177 case FB_VISUAL_PSEUDOCOLOR:
178 writew((red & 0xf800)
179 | ((green >> 5) & 0x7e0)
180 | ((blue >> 11) & 0x1f),
181 fbi->palette_cpu + sizeof(u16) * regno);
182 break;
183 }
184
185 return ret;
186 }
187
vt8500lcd_ioctl(struct fb_info * info,unsigned int cmd,unsigned long arg)188 static int vt8500lcd_ioctl(struct fb_info *info, unsigned int cmd,
189 unsigned long arg)
190 {
191 int ret = 0;
192 struct vt8500lcd_info *fbi = to_vt8500lcd_info(info);
193
194 if (cmd == FBIO_WAITFORVSYNC) {
195 /* Unmask End of Frame interrupt */
196 writel(0xffffffff ^ (1 << 3), fbi->regbase + 0x3c);
197 ret = wait_event_interruptible_timeout(fbi->wait,
198 readl(fbi->regbase + 0x38) & (1 << 3), HZ / 10);
199 /* Mask back to reduce unwanted interrupt traffic */
200 writel(0xffffffff, fbi->regbase + 0x3c);
201 if (ret < 0)
202 return ret;
203 if (ret == 0)
204 return -ETIMEDOUT;
205 }
206
207 return ret;
208 }
209
vt8500lcd_pan_display(struct fb_var_screeninfo * var,struct fb_info * info)210 static int vt8500lcd_pan_display(struct fb_var_screeninfo *var,
211 struct fb_info *info)
212 {
213 unsigned pixlen = info->fix.line_length / info->var.xres_virtual;
214 unsigned off = pixlen * var->xoffset
215 + info->fix.line_length * var->yoffset;
216 struct vt8500lcd_info *fbi = to_vt8500lcd_info(info);
217
218 writel((1 << 31)
219 | (((info->var.xres_virtual - info->var.xres) * pixlen / 4) << 20)
220 | (off >> 2), fbi->regbase + 0x20);
221 return 0;
222 }
223
224 /*
225 * vt8500lcd_blank():
226 * Blank the display by setting all palette values to zero. Note,
227 * True Color modes do not really use the palette, so this will not
228 * blank the display in all modes.
229 */
vt8500lcd_blank(int blank,struct fb_info * info)230 static int vt8500lcd_blank(int blank, struct fb_info *info)
231 {
232 int i;
233
234 switch (blank) {
235 case FB_BLANK_POWERDOWN:
236 case FB_BLANK_VSYNC_SUSPEND:
237 case FB_BLANK_HSYNC_SUSPEND:
238 case FB_BLANK_NORMAL:
239 if (info->fix.visual == FB_VISUAL_PSEUDOCOLOR ||
240 info->fix.visual == FB_VISUAL_STATIC_PSEUDOCOLOR)
241 for (i = 0; i < 256; i++)
242 vt8500lcd_setcolreg(i, 0, 0, 0, 0, info);
243 case FB_BLANK_UNBLANK:
244 if (info->fix.visual == FB_VISUAL_PSEUDOCOLOR ||
245 info->fix.visual == FB_VISUAL_STATIC_PSEUDOCOLOR)
246 fb_set_cmap(&info->cmap, info);
247 }
248 return 0;
249 }
250
251 static struct fb_ops vt8500lcd_ops = {
252 .owner = THIS_MODULE,
253 .fb_set_par = vt8500lcd_set_par,
254 .fb_setcolreg = vt8500lcd_setcolreg,
255 .fb_fillrect = wmt_ge_fillrect,
256 .fb_copyarea = wmt_ge_copyarea,
257 .fb_imageblit = sys_imageblit,
258 .fb_sync = wmt_ge_sync,
259 .fb_ioctl = vt8500lcd_ioctl,
260 .fb_pan_display = vt8500lcd_pan_display,
261 .fb_blank = vt8500lcd_blank,
262 };
263
vt8500lcd_handle_irq(int irq,void * dev_id)264 static irqreturn_t vt8500lcd_handle_irq(int irq, void *dev_id)
265 {
266 struct vt8500lcd_info *fbi = dev_id;
267
268 if (readl(fbi->regbase + 0x38) & (1 << 3))
269 wake_up_interruptible(&fbi->wait);
270
271 writel(0xffffffff, fbi->regbase + 0x38);
272 return IRQ_HANDLED;
273 }
274
vt8500lcd_probe(struct platform_device * pdev)275 static int vt8500lcd_probe(struct platform_device *pdev)
276 {
277 struct vt8500lcd_info *fbi;
278 struct resource *res;
279 struct display_timings *disp_timing;
280 void *addr;
281 int irq, ret;
282
283 struct fb_videomode of_mode;
284 u32 bpp;
285 dma_addr_t fb_mem_phys;
286 unsigned long fb_mem_len;
287 void *fb_mem_virt;
288
289 ret = -ENOMEM;
290 fbi = NULL;
291
292 fbi = devm_kzalloc(&pdev->dev, sizeof(struct vt8500lcd_info)
293 + sizeof(u32) * 16, GFP_KERNEL);
294 if (!fbi) {
295 dev_err(&pdev->dev, "Failed to initialize framebuffer device\n");
296 ret = -ENOMEM;
297 goto failed;
298 }
299
300 strcpy(fbi->fb.fix.id, "VT8500 LCD");
301
302 fbi->fb.fix.type = FB_TYPE_PACKED_PIXELS;
303 fbi->fb.fix.xpanstep = 0;
304 fbi->fb.fix.ypanstep = 1;
305 fbi->fb.fix.ywrapstep = 0;
306 fbi->fb.fix.accel = FB_ACCEL_NONE;
307
308 fbi->fb.var.nonstd = 0;
309 fbi->fb.var.activate = FB_ACTIVATE_NOW;
310 fbi->fb.var.height = -1;
311 fbi->fb.var.width = -1;
312 fbi->fb.var.vmode = FB_VMODE_NONINTERLACED;
313
314 fbi->fb.fbops = &vt8500lcd_ops;
315 fbi->fb.flags = FBINFO_DEFAULT
316 | FBINFO_HWACCEL_COPYAREA
317 | FBINFO_HWACCEL_FILLRECT
318 | FBINFO_HWACCEL_YPAN
319 | FBINFO_VIRTFB
320 | FBINFO_PARTIAL_PAN_OK;
321 fbi->fb.node = -1;
322
323 addr = fbi;
324 addr = addr + sizeof(struct vt8500lcd_info);
325 fbi->fb.pseudo_palette = addr;
326
327 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
328 if (res == NULL) {
329 dev_err(&pdev->dev, "no I/O memory resource defined\n");
330 ret = -ENODEV;
331 goto failed_fbi;
332 }
333
334 res = request_mem_region(res->start, resource_size(res), "vt8500lcd");
335 if (res == NULL) {
336 dev_err(&pdev->dev, "failed to request I/O memory\n");
337 ret = -EBUSY;
338 goto failed_fbi;
339 }
340
341 fbi->regbase = ioremap(res->start, resource_size(res));
342 if (fbi->regbase == NULL) {
343 dev_err(&pdev->dev, "failed to map I/O memory\n");
344 ret = -EBUSY;
345 goto failed_free_res;
346 }
347
348 disp_timing = of_get_display_timings(pdev->dev.of_node);
349 if (!disp_timing)
350 return -EINVAL;
351
352 ret = of_get_fb_videomode(pdev->dev.of_node, &of_mode,
353 OF_USE_NATIVE_MODE);
354 if (ret)
355 return ret;
356
357 ret = of_property_read_u32(pdev->dev.of_node, "bits-per-pixel", &bpp);
358 if (ret)
359 return ret;
360
361 /* try allocating the framebuffer */
362 fb_mem_len = of_mode.xres * of_mode.yres * 2 * (bpp / 8);
363 fb_mem_virt = dma_alloc_coherent(&pdev->dev, fb_mem_len, &fb_mem_phys,
364 GFP_KERNEL);
365 if (!fb_mem_virt) {
366 pr_err("%s: Failed to allocate framebuffer\n", __func__);
367 return -ENOMEM;
368 };
369
370 fbi->fb.fix.smem_start = fb_mem_phys;
371 fbi->fb.fix.smem_len = fb_mem_len;
372 fbi->fb.screen_base = fb_mem_virt;
373
374 fbi->palette_size = PAGE_ALIGN(512);
375 fbi->palette_cpu = dma_alloc_coherent(&pdev->dev,
376 fbi->palette_size,
377 &fbi->palette_phys,
378 GFP_KERNEL);
379 if (fbi->palette_cpu == NULL) {
380 dev_err(&pdev->dev, "Failed to allocate palette buffer\n");
381 ret = -ENOMEM;
382 goto failed_free_io;
383 }
384
385 irq = platform_get_irq(pdev, 0);
386 if (irq < 0) {
387 dev_err(&pdev->dev, "no IRQ defined\n");
388 ret = -ENODEV;
389 goto failed_free_palette;
390 }
391
392 ret = request_irq(irq, vt8500lcd_handle_irq, 0, "LCD", fbi);
393 if (ret) {
394 dev_err(&pdev->dev, "request_irq failed: %d\n", ret);
395 ret = -EBUSY;
396 goto failed_free_palette;
397 }
398
399 init_waitqueue_head(&fbi->wait);
400
401 if (fb_alloc_cmap(&fbi->fb.cmap, 256, 0) < 0) {
402 dev_err(&pdev->dev, "Failed to allocate color map\n");
403 ret = -ENOMEM;
404 goto failed_free_irq;
405 }
406
407 fb_videomode_to_var(&fbi->fb.var, &of_mode);
408
409 fbi->fb.var.xres_virtual = of_mode.xres;
410 fbi->fb.var.yres_virtual = of_mode.yres * 2;
411 fbi->fb.var.bits_per_pixel = bpp;
412
413 ret = vt8500lcd_set_par(&fbi->fb);
414 if (ret) {
415 dev_err(&pdev->dev, "Failed to set parameters\n");
416 goto failed_free_cmap;
417 }
418
419 writel(fbi->fb.fix.smem_start >> 22, fbi->regbase + 0x1c);
420 writel((fbi->palette_phys & 0xfffffe00) | 1, fbi->regbase + 0x18);
421
422 platform_set_drvdata(pdev, fbi);
423
424 ret = register_framebuffer(&fbi->fb);
425 if (ret < 0) {
426 dev_err(&pdev->dev,
427 "Failed to register framebuffer device: %d\n", ret);
428 goto failed_free_cmap;
429 }
430
431 /*
432 * Ok, now enable the LCD controller
433 */
434 writel(readl(fbi->regbase) | 1, fbi->regbase);
435
436 return 0;
437
438 failed_free_cmap:
439 if (fbi->fb.cmap.len)
440 fb_dealloc_cmap(&fbi->fb.cmap);
441 failed_free_irq:
442 free_irq(irq, fbi);
443 failed_free_palette:
444 dma_free_coherent(&pdev->dev, fbi->palette_size,
445 fbi->palette_cpu, fbi->palette_phys);
446 failed_free_io:
447 iounmap(fbi->regbase);
448 failed_free_res:
449 release_mem_region(res->start, resource_size(res));
450 failed_fbi:
451 platform_set_drvdata(pdev, NULL);
452 kfree(fbi);
453 failed:
454 return ret;
455 }
456
vt8500lcd_remove(struct platform_device * pdev)457 static int vt8500lcd_remove(struct platform_device *pdev)
458 {
459 struct vt8500lcd_info *fbi = platform_get_drvdata(pdev);
460 struct resource *res;
461 int irq;
462
463 unregister_framebuffer(&fbi->fb);
464
465 writel(0, fbi->regbase);
466
467 if (fbi->fb.cmap.len)
468 fb_dealloc_cmap(&fbi->fb.cmap);
469
470 irq = platform_get_irq(pdev, 0);
471 free_irq(irq, fbi);
472
473 dma_free_coherent(&pdev->dev, fbi->palette_size,
474 fbi->palette_cpu, fbi->palette_phys);
475
476 iounmap(fbi->regbase);
477
478 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
479 release_mem_region(res->start, resource_size(res));
480
481 kfree(fbi);
482
483 return 0;
484 }
485
486 static const struct of_device_id via_dt_ids[] = {
487 { .compatible = "via,vt8500-fb", },
488 {}
489 };
490
491 static struct platform_driver vt8500lcd_driver = {
492 .probe = vt8500lcd_probe,
493 .remove = vt8500lcd_remove,
494 .driver = {
495 .owner = THIS_MODULE,
496 .name = "vt8500-lcd",
497 .of_match_table = of_match_ptr(via_dt_ids),
498 },
499 };
500
501 module_platform_driver(vt8500lcd_driver);
502
503 MODULE_AUTHOR("Alexey Charkov <alchark@gmail.com>");
504 MODULE_DESCRIPTION("LCD controller driver for VIA VT8500");
505 MODULE_LICENSE("GPL v2");
506 MODULE_DEVICE_TABLE(of, via_dt_ids);
507