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[POWERPC] Add error return from htab_remove_mapping()
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / video / imxfb.c
blob11609552a387301bc00515ca75b3af0c37d21b56
1 /*
2 * linux/drivers/video/imxfb.c
3 *
4 * Freescale i.MX Frame Buffer device driver
5 *
6 * Copyright (C) 2004 Sascha Hauer, Pengutronix
7 * Based on acornfb.c Copyright (C) Russell King.
8 *
9 * This file is subject to the terms and conditions of the GNU General Public
10 * License. See the file COPYING in the main directory of this archive for
11 * more details.
12 *
13 * Please direct your questions and comments on this driver to the following
14 * email address:
15 *
16 * linux-arm-kernel@lists.arm.linux.org.uk
17 */
18
19 //#define DEBUG 1
20
21 #include <linux/module.h>
22 #include <linux/kernel.h>
23 #include <linux/errno.h>
24 #include <linux/string.h>
25 #include <linux/interrupt.h>
26 #include <linux/slab.h>
27 #include <linux/fb.h>
28 #include <linux/delay.h>
29 #include <linux/init.h>
30 #include <linux/ioport.h>
31 #include <linux/cpufreq.h>
32 #include <linux/platform_device.h>
33 #include <linux/dma-mapping.h>
34
35 #include <asm/hardware.h>
36 #include <asm/io.h>
37 #include <asm/arch/imxfb.h>
38
39 /*
40 * Complain if VAR is out of range.
41 */
42 #define DEBUG_VAR 1
43
44 #include "imxfb.h"
45
46 static struct imxfb_rgb def_rgb_16 = {
47 .red = { .offset = 8, .length = 4, },
48 .green = { .offset = 4, .length = 4, },
49 .blue = { .offset = 0, .length = 4, },
50 .transp = { .offset = 0, .length = 0, },
51 };
52
53 static struct imxfb_rgb def_rgb_8 = {
54 .red = { .offset = 0, .length = 8, },
55 .green = { .offset = 0, .length = 8, },
56 .blue = { .offset = 0, .length = 8, },
57 .transp = { .offset = 0, .length = 0, },
58 };
59
60 static int imxfb_activate_var(struct fb_var_screeninfo *var, struct fb_info *info);
61
62 static inline u_int chan_to_field(u_int chan, struct fb_bitfield *bf)
63 {
64 chan &= 0xffff;
65 chan >>= 16 - bf->length;
66 return chan << bf->offset;
67 }
68
69 #define LCDC_PALETTE(x) __REG2(IMX_LCDC_BASE+0x800, (x)<<2)
70 static int
71 imxfb_setpalettereg(u_int regno, u_int red, u_int green, u_int blue,
72 u_int trans, struct fb_info *info)
73 {
74 struct imxfb_info *fbi = info->par;
75 u_int val, ret = 1;
76
77 #define CNVT_TOHW(val,width) ((((val)<<(width))+0x7FFF-(val))>>16)
78 if (regno < fbi->palette_size) {
79 val = (CNVT_TOHW(red, 4) << 8) |
80 (CNVT_TOHW(green,4) << 4) |
81 CNVT_TOHW(blue, 4);
82
83 LCDC_PALETTE(regno) = val;
84 ret = 0;
85 }
86 return ret;
87 }
88
89 static int
90 imxfb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
91 u_int trans, struct fb_info *info)
92 {
93 struct imxfb_info *fbi = info->par;
94 unsigned int val;
95 int ret = 1;
96
97 /*
98 * If inverse mode was selected, invert all the colours
99 * rather than the register number. The register number
100 * is what you poke into the framebuffer to produce the
101 * colour you requested.
102 */
103 if (fbi->cmap_inverse) {
104 red = 0xffff - red;
105 green = 0xffff - green;
106 blue = 0xffff - blue;
107 }
108
109 /*
110 * If greyscale is true, then we convert the RGB value
111 * to greyscale no mater what visual we are using.
112 */
113 if (info->var.grayscale)
114 red = green = blue = (19595 * red + 38470 * green +
115 7471 * blue) >> 16;
116
117 switch (info->fix.visual) {
118 case FB_VISUAL_TRUECOLOR:
119 /*
120 * 12 or 16-bit True Colour. We encode the RGB value
121 * according to the RGB bitfield information.
122 */
123 if (regno < 16) {
124 u32 *pal = info->pseudo_palette;
125
126 val = chan_to_field(red, &info->var.red);
127 val |= chan_to_field(green, &info->var.green);
128 val |= chan_to_field(blue, &info->var.blue);
129
130 pal[regno] = val;
131 ret = 0;
132 }
133 break;
134
135 case FB_VISUAL_STATIC_PSEUDOCOLOR:
136 case FB_VISUAL_PSEUDOCOLOR:
137 ret = imxfb_setpalettereg(regno, red, green, blue, trans, info);
138 break;
139 }
140
141 return ret;
142 }
143
144 /*
145 * imxfb_check_var():
146 * Round up in the following order: bits_per_pixel, xres,
147 * yres, xres_virtual, yres_virtual, xoffset, yoffset, grayscale,
148 * bitfields, horizontal timing, vertical timing.
149 */
150 static int
151 imxfb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
152 {
153 struct imxfb_info *fbi = info->par;
154 int rgbidx;
155
156 if (var->xres < MIN_XRES)
157 var->xres = MIN_XRES;
158 if (var->yres < MIN_YRES)
159 var->yres = MIN_YRES;
160 if (var->xres > fbi->max_xres)
161 var->xres = fbi->max_xres;
162 if (var->yres > fbi->max_yres)
163 var->yres = fbi->max_yres;
164 var->xres_virtual = max(var->xres_virtual, var->xres);
165 var->yres_virtual = max(var->yres_virtual, var->yres);
166
167 pr_debug("var->bits_per_pixel=%d\n", var->bits_per_pixel);
168 switch (var->bits_per_pixel) {
169 case 16:
170 rgbidx = RGB_16;
171 break;
172 case 8:
173 rgbidx = RGB_8;
174 break;
175 default:
176 rgbidx = RGB_16;
177 }
178
179 /*
180 * Copy the RGB parameters for this display
181 * from the machine specific parameters.
182 */
183 var->red = fbi->rgb[rgbidx]->red;
184 var->green = fbi->rgb[rgbidx]->green;
185 var->blue = fbi->rgb[rgbidx]->blue;
186 var->transp = fbi->rgb[rgbidx]->transp;
187
188 pr_debug("RGBT length = %d:%d:%d:%d\n",
189 var->red.length, var->green.length, var->blue.length,
190 var->transp.length);
191
192 pr_debug("RGBT offset = %d:%d:%d:%d\n",
193 var->red.offset, var->green.offset, var->blue.offset,
194 var->transp.offset);
195
196 return 0;
197 }
198
199 /*
200 * imxfb_set_par():
201 * Set the user defined part of the display for the specified console
202 */
203 static int imxfb_set_par(struct fb_info *info)
204 {
205 struct imxfb_info *fbi = info->par;
206 struct fb_var_screeninfo *var = &info->var;
207
208 pr_debug("set_par\n");
209
210 if (var->bits_per_pixel == 16)
211 info->fix.visual = FB_VISUAL_TRUECOLOR;
212 else if (!fbi->cmap_static)
213 info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
214 else {
215 /*
216 * Some people have weird ideas about wanting static
217 * pseudocolor maps. I suspect their user space
218 * applications are broken.
219 */
220 info->fix.visual = FB_VISUAL_STATIC_PSEUDOCOLOR;
221 }
222
223 info->fix.line_length = var->xres_virtual *
224 var->bits_per_pixel / 8;
225 fbi->palette_size = var->bits_per_pixel == 8 ? 256 : 16;
226
227 imxfb_activate_var(var, info);
228
229 return 0;
230 }
231
232 static void imxfb_enable_controller(struct imxfb_info *fbi)
233 {
234 pr_debug("Enabling LCD controller\n");
235
236 /* initialize LCDC */
237 LCDC_RMCR &= ~RMCR_LCDC_EN; /* just to be safe... */
238
239 LCDC_SSA = fbi->screen_dma;
240 /* physical screen start address */
241 LCDC_VPW = VPW_VPW(fbi->max_xres * fbi->max_bpp / 8 / 4);
242
243 LCDC_POS = 0x00000000; /* panning offset 0 (0 pixel offset) */
244
245 /* disable hardware cursor */
246 LCDC_CPOS &= ~(CPOS_CC0 | CPOS_CC1);
247
248 LCDC_RMCR = RMCR_LCDC_EN;
249
250 if(fbi->backlight_power)
251 fbi->backlight_power(1);
252 if(fbi->lcd_power)
253 fbi->lcd_power(1);
254 }
255
256 static void imxfb_disable_controller(struct imxfb_info *fbi)
257 {
258 pr_debug("Disabling LCD controller\n");
259
260 if(fbi->backlight_power)
261 fbi->backlight_power(0);
262 if(fbi->lcd_power)
263 fbi->lcd_power(0);
264
265 LCDC_RMCR = 0;
266 }
267
268 static int imxfb_blank(int blank, struct fb_info *info)
269 {
270 struct imxfb_info *fbi = info->par;
271
272 pr_debug("imxfb_blank: blank=%d\n", blank);
273
274 switch (blank) {
275 case FB_BLANK_POWERDOWN:
276 case FB_BLANK_VSYNC_SUSPEND:
277 case FB_BLANK_HSYNC_SUSPEND:
278 case FB_BLANK_NORMAL:
279 imxfb_disable_controller(fbi);
280 break;
281
282 case FB_BLANK_UNBLANK:
283 imxfb_enable_controller(fbi);
284 break;
285 }
286 return 0;
287 }
288
289 static struct fb_ops imxfb_ops = {
290 .owner = THIS_MODULE,
291 .fb_check_var = imxfb_check_var,
292 .fb_set_par = imxfb_set_par,
293 .fb_setcolreg = imxfb_setcolreg,
294 .fb_fillrect = cfb_fillrect,
295 .fb_copyarea = cfb_copyarea,
296 .fb_imageblit = cfb_imageblit,
297 .fb_blank = imxfb_blank,
298 };
299
300 /*
301 * imxfb_activate_var():
302 * Configures LCD Controller based on entries in var parameter. Settings are
303 * only written to the controller if changes were made.
304 */
305 static int imxfb_activate_var(struct fb_var_screeninfo *var, struct fb_info *info)
306 {
307 struct imxfb_info *fbi = info->par;
308 pr_debug("var: xres=%d hslen=%d lm=%d rm=%d\n",
309 var->xres, var->hsync_len,
310 var->left_margin, var->right_margin);
311 pr_debug("var: yres=%d vslen=%d um=%d bm=%d\n",
312 var->yres, var->vsync_len,
313 var->upper_margin, var->lower_margin);
314
315 #if DEBUG_VAR
316 if (var->xres < 16 || var->xres > 1024)
317 printk(KERN_ERR "%s: invalid xres %d\n",
318 info->fix.id, var->xres);
319 if (var->hsync_len < 1 || var->hsync_len > 64)
320 printk(KERN_ERR "%s: invalid hsync_len %d\n",
321 info->fix.id, var->hsync_len);
322 if (var->left_margin > 255)
323 printk(KERN_ERR "%s: invalid left_margin %d\n",
324 info->fix.id, var->left_margin);
325 if (var->right_margin > 255)
326 printk(KERN_ERR "%s: invalid right_margin %d\n",
327 info->fix.id, var->right_margin);
328 if (var->yres < 1 || var->yres > 511)
329 printk(KERN_ERR "%s: invalid yres %d\n",
330 info->fix.id, var->yres);
331 if (var->vsync_len > 100)
332 printk(KERN_ERR "%s: invalid vsync_len %d\n",
333 info->fix.id, var->vsync_len);
334 if (var->upper_margin > 63)
335 printk(KERN_ERR "%s: invalid upper_margin %d\n",
336 info->fix.id, var->upper_margin);
337 if (var->lower_margin > 255)
338 printk(KERN_ERR "%s: invalid lower_margin %d\n",
339 info->fix.id, var->lower_margin);
340 #endif
341
342 LCDC_HCR = HCR_H_WIDTH(var->hsync_len) |
343 HCR_H_WAIT_1(var->left_margin) |
344 HCR_H_WAIT_2(var->right_margin);
345
346 LCDC_VCR = VCR_V_WIDTH(var->vsync_len) |
347 VCR_V_WAIT_1(var->upper_margin) |
348 VCR_V_WAIT_2(var->lower_margin);
349
350 LCDC_SIZE = SIZE_XMAX(var->xres) | SIZE_YMAX(var->yres);
351 LCDC_PCR = fbi->pcr;
352 LCDC_PWMR = fbi->pwmr;
353 LCDC_LSCR1 = fbi->lscr1;
354 LCDC_DMACR = fbi->dmacr;
355
356 return 0;
357 }
358
359 static void imxfb_setup_gpio(struct imxfb_info *fbi)
360 {
361 int width;
362
363 LCDC_RMCR &= ~(RMCR_LCDC_EN | RMCR_SELF_REF);
364
365 if( fbi->pcr & PCR_TFT )
366 width = 16;
367 else
368 width = 1 << ((fbi->pcr >> 28) & 0x3);
369
370 switch(width) {
371 case 16:
372 imx_gpio_mode(PD30_PF_LD15);
373 imx_gpio_mode(PD29_PF_LD14);
374 imx_gpio_mode(PD28_PF_LD13);
375 imx_gpio_mode(PD27_PF_LD12);
376 imx_gpio_mode(PD26_PF_LD11);
377 imx_gpio_mode(PD25_PF_LD10);
378 imx_gpio_mode(PD24_PF_LD9);
379 imx_gpio_mode(PD23_PF_LD8);
380 case 8:
381 imx_gpio_mode(PD22_PF_LD7);
382 imx_gpio_mode(PD21_PF_LD6);
383 imx_gpio_mode(PD20_PF_LD5);
384 imx_gpio_mode(PD19_PF_LD4);
385 case 4:
386 imx_gpio_mode(PD18_PF_LD3);
387 imx_gpio_mode(PD17_PF_LD2);
388 case 2:
389 imx_gpio_mode(PD16_PF_LD1);
390 case 1:
391 imx_gpio_mode(PD15_PF_LD0);
392 }
393
394 /* initialize GPIOs */
395 imx_gpio_mode(PD6_PF_LSCLK);
396 imx_gpio_mode(PD11_PF_CONTRAST);
397 imx_gpio_mode(PD14_PF_FLM_VSYNC);
398 imx_gpio_mode(PD13_PF_LP_HSYNC);
399 imx_gpio_mode(PD12_PF_ACD_OE);
400
401 /* These are only needed for Sharp HR TFT displays */
402 if (fbi->pcr & PCR_SHARP) {
403 imx_gpio_mode(PD7_PF_REV);
404 imx_gpio_mode(PD8_PF_CLS);
405 imx_gpio_mode(PD9_PF_PS);
406 imx_gpio_mode(PD10_PF_SPL_SPR);
407 }
408 }
409
410 #ifdef CONFIG_PM
411 /*
412 * Power management hooks. Note that we won't be called from IRQ context,
413 * unlike the blank functions above, so we may sleep.
414 */
415 static int imxfb_suspend(struct platform_device *dev, pm_message_t state)
416 {
417 struct imxfb_info *fbi = platform_get_drvdata(dev);
418 pr_debug("%s\n",__FUNCTION__);
419
420 imxfb_disable_controller(fbi);
421 return 0;
422 }
423
424 static int imxfb_resume(struct platform_device *dev)
425 {
426 struct imxfb_info *fbi = platform_get_drvdata(dev);
427 pr_debug("%s\n",__FUNCTION__);
428
429 imxfb_enable_controller(fbi);
430 return 0;
431 }
432 #else
433 #define imxfb_suspend NULL
434 #define imxfb_resume NULL
435 #endif
436
437 static int __init imxfb_init_fbinfo(struct device *dev)
438 {
439 struct imxfb_mach_info *inf = dev->platform_data;
440 struct fb_info *info = dev_get_drvdata(dev);
441 struct imxfb_info *fbi = info->par;
442
443 pr_debug("%s\n",__FUNCTION__);
444
445 info->pseudo_palette = kmalloc( sizeof(u32) * 16, GFP_KERNEL);
446 if (!info->pseudo_palette)
447 return -ENOMEM;
448
449 memset(fbi, 0, sizeof(struct imxfb_info));
450 fbi->dev = dev;
451
452 strlcpy(info->fix.id, IMX_NAME, sizeof(info->fix.id));
453
454 info->fix.type = FB_TYPE_PACKED_PIXELS;
455 info->fix.type_aux = 0;
456 info->fix.xpanstep = 0;
457 info->fix.ypanstep = 0;
458 info->fix.ywrapstep = 0;
459 info->fix.accel = FB_ACCEL_NONE;
460
461 info->var.nonstd = 0;
462 info->var.activate = FB_ACTIVATE_NOW;
463 info->var.height = -1;
464 info->var.width = -1;
465 info->var.accel_flags = 0;
466 info->var.vmode = FB_VMODE_NONINTERLACED;
467
468 info->fbops = &imxfb_ops;
469 info->flags = FBINFO_FLAG_DEFAULT | FBINFO_READS_FAST;
470
471 fbi->rgb[RGB_16] = &def_rgb_16;
472 fbi->rgb[RGB_8] = &def_rgb_8;
473
474 fbi->max_xres = inf->xres;
475 info->var.xres = inf->xres;
476 info->var.xres_virtual = inf->xres;
477 fbi->max_yres = inf->yres;
478 info->var.yres = inf->yres;
479 info->var.yres_virtual = inf->yres;
480 fbi->max_bpp = inf->bpp;
481 info->var.bits_per_pixel = inf->bpp;
482 info->var.nonstd = inf->nonstd;
483 info->var.pixclock = inf->pixclock;
484 info->var.hsync_len = inf->hsync_len;
485 info->var.left_margin = inf->left_margin;
486 info->var.right_margin = inf->right_margin;
487 info->var.vsync_len = inf->vsync_len;
488 info->var.upper_margin = inf->upper_margin;
489 info->var.lower_margin = inf->lower_margin;
490 info->var.sync = inf->sync;
491 info->var.grayscale = inf->cmap_greyscale;
492 fbi->cmap_inverse = inf->cmap_inverse;
493 fbi->cmap_static = inf->cmap_static;
494 fbi->pcr = inf->pcr;
495 fbi->lscr1 = inf->lscr1;
496 fbi->dmacr = inf->dmacr;
497 fbi->pwmr = inf->pwmr;
498 fbi->lcd_power = inf->lcd_power;
499 fbi->backlight_power = inf->backlight_power;
500 info->fix.smem_len = fbi->max_xres * fbi->max_yres *
501 fbi->max_bpp / 8;
502
503 return 0;
504 }
505
506 /*
507 * Allocates the DRAM memory for the frame buffer. This buffer is
508 * remapped into a non-cached, non-buffered, memory region to
509 * allow pixel writes to occur without flushing the cache.
510 * Once this area is remapped, all virtual memory access to the
511 * video memory should occur at the new region.
512 */
513 static int __init imxfb_map_video_memory(struct fb_info *info)
514 {
515 struct imxfb_info *fbi = info->par;
516
517 fbi->map_size = PAGE_ALIGN(info->fix.smem_len);
518 fbi->map_cpu = dma_alloc_writecombine(fbi->dev, fbi->map_size,
519 &fbi->map_dma,GFP_KERNEL);
520
521 if (fbi->map_cpu) {
522 info->screen_base = fbi->map_cpu;
523 fbi->screen_cpu = fbi->map_cpu;
524 fbi->screen_dma = fbi->map_dma;
525 info->fix.smem_start = fbi->screen_dma;
526 }
527
528 return fbi->map_cpu ? 0 : -ENOMEM;
529 }
530
531 static int __init imxfb_probe(struct platform_device *pdev)
532 {
533 struct imxfb_info *fbi;
534 struct fb_info *info;
535 struct imxfb_mach_info *inf;
536 struct resource *res;
537 int ret;
538
539 printk("i.MX Framebuffer driver\n");
540
541 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
542 if(!res)
543 return -ENODEV;
544
545 inf = pdev->dev.platform_data;
546 if(!inf) {
547 dev_err(&pdev->dev,"No platform_data available\n");
548 return -ENOMEM;
549 }
550
551 info = framebuffer_alloc(sizeof(struct imxfb_info), &pdev->dev);
552 if(!info)
553 return -ENOMEM;
554
555 fbi = info->par;
556
557 platform_set_drvdata(pdev, info);
558
559 ret = imxfb_init_fbinfo(&pdev->dev);
560 if( ret < 0 )
561 goto failed_init;
562
563 res = request_mem_region(res->start, res->end - res->start + 1, "IMXFB");
564 if (!res) {
565 ret = -EBUSY;
566 goto failed_regs;
567 }
568
569 if (!inf->fixed_screen_cpu) {
570 ret = imxfb_map_video_memory(info);
571 if (ret) {
572 dev_err(&pdev->dev, "Failed to allocate video RAM: %d\n", ret);
573 ret = -ENOMEM;
574 goto failed_map;
575 }
576 } else {
577 /* Fixed framebuffer mapping enables location of the screen in eSRAM */
578 fbi->map_cpu = inf->fixed_screen_cpu;
579 fbi->map_dma = inf->fixed_screen_dma;
580 info->screen_base = fbi->map_cpu;
581 fbi->screen_cpu = fbi->map_cpu;
582 fbi->screen_dma = fbi->map_dma;
583 info->fix.smem_start = fbi->screen_dma;
584 }
585
586 /*
587 * This makes sure that our colour bitfield
588 * descriptors are correctly initialised.
589 */
590 imxfb_check_var(&info->var, info);
591
592 ret = fb_alloc_cmap(&info->cmap, 1<<info->var.bits_per_pixel, 0);
593 if (ret < 0)
594 goto failed_cmap;
595
596 imxfb_setup_gpio(fbi);
597
598 imxfb_set_par(info);
599 ret = register_framebuffer(info);
600 if (ret < 0) {
601 dev_err(&pdev->dev, "failed to register framebuffer\n");
602 goto failed_register;
603 }
604
605 imxfb_enable_controller(fbi);
606
607 return 0;
608
609 failed_register:
610 fb_dealloc_cmap(&info->cmap);
611 failed_cmap:
612 if (!inf->fixed_screen_cpu)
613 dma_free_writecombine(&pdev->dev,fbi->map_size,fbi->map_cpu,
614 fbi->map_dma);
615 failed_map:
616 kfree(info->pseudo_palette);
617 failed_regs:
618 release_mem_region(res->start, res->end - res->start);
619 failed_init:
620 platform_set_drvdata(pdev, NULL);
621 framebuffer_release(info);
622 return ret;
623 }
624
625 static int imxfb_remove(struct platform_device *pdev)
626 {
627 struct fb_info *info = platform_get_drvdata(pdev);
628 struct imxfb_info *fbi = info->par;
629 struct resource *res;
630
631 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
632
633 imxfb_disable_controller(fbi);
634
635 unregister_framebuffer(info);
636
637 fb_dealloc_cmap(&info->cmap);
638 kfree(info->pseudo_palette);
639 framebuffer_release(info);
640
641 release_mem_region(res->start, res->end - res->start + 1);
642 platform_set_drvdata(pdev, NULL);
643
644 return 0;
645 }
646
647 void imxfb_shutdown(struct platform_device * dev)
648 {
649 struct fb_info *info = platform_get_drvdata(dev);
650 struct imxfb_info *fbi = info->par;
651 imxfb_disable_controller(fbi);
652 }
653
654 static struct platform_driver imxfb_driver = {
655 .probe = imxfb_probe,
656 .suspend = imxfb_suspend,
657 .resume = imxfb_resume,
658 .remove = imxfb_remove,
659 .shutdown = imxfb_shutdown,
660 .driver = {
661 .name = "imx-fb",
662 },
663 };
664
665 int __init imxfb_init(void)
666 {
667 return platform_driver_register(&imxfb_driver);
668 }
669
670 static void __exit imxfb_cleanup(void)
671 {
672 platform_driver_unregister(&imxfb_driver);
673 }
674
675 module_init(imxfb_init);
676 module_exit(imxfb_cleanup);
677
678 MODULE_DESCRIPTION("Motorola i.MX framebuffer driver");
679 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
680 MODULE_LICENSE("GPL");
Linux 2.6 ibm-acpi/thinkpad-acpi driver git tree