backlight: add backlight driver for pandora
[pandora-kernel.git] / drivers / video / vt8500lcdfb.c
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/module.h>
19 #include <linux/kernel.h>
20 #include <linux/errno.h>
21 #include <linux/string.h>
22 #include <linux/mm.h>
23 #include <linux/slab.h>
24 #include <linux/delay.h>
25 #include <linux/fb.h>
26 #include <linux/init.h>
27 #include <linux/interrupt.h>
28 #include <linux/io.h>
29 #include <linux/dma-mapping.h>
30 #include <linux/platform_device.h>
31 #include <linux/wait.h>
32
33 #include <mach/vt8500fb.h>
34
35 #include "vt8500lcdfb.h"
36 #include "wmt_ge_rops.h"
37
38 #define to_vt8500lcd_info(__info) container_of(__info, \
39                                                 struct vt8500lcd_info, fb)
40
41 static int vt8500lcd_set_par(struct fb_info *info)
42 {
43         struct vt8500lcd_info *fbi = to_vt8500lcd_info(info);
44         int reg_bpp = 5; /* 16bpp */
45         int i;
46         unsigned long control0;
47
48         if (!fbi)
49                 return -EINVAL;
50
51         if (info->var.bits_per_pixel <= 8) {
52                 /* palettized */
53                 info->var.red.offset    = 0;
54                 info->var.red.length    = info->var.bits_per_pixel;
55                 info->var.red.msb_right = 0;
56
57                 info->var.green.offset  = 0;
58                 info->var.green.length  = info->var.bits_per_pixel;
59                 info->var.green.msb_right = 0;
60
61                 info->var.blue.offset   = 0;
62                 info->var.blue.length   = info->var.bits_per_pixel;
63                 info->var.blue.msb_right = 0;
64
65                 info->var.transp.offset = 0;
66                 info->var.transp.length = 0;
67                 info->var.transp.msb_right = 0;
68
69                 info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
70                 info->fix.line_length = info->var.xres_virtual /
71                                                 (8/info->var.bits_per_pixel);
72         } else {
73                 /* non-palettized */
74                 info->var.transp.offset = 0;
75                 info->var.transp.length = 0;
76                 info->var.transp.msb_right = 0;
77
78                 if (info->var.bits_per_pixel == 16) {
79                         /* RGB565 */
80                         info->var.red.offset = 11;
81                         info->var.red.length = 5;
82                         info->var.red.msb_right = 0;
83                         info->var.green.offset = 5;
84                         info->var.green.length = 6;
85                         info->var.green.msb_right = 0;
86                         info->var.blue.offset = 0;
87                         info->var.blue.length = 5;
88                         info->var.blue.msb_right = 0;
89                 } else {
90                         /* Equal depths per channel */
91                         info->var.red.offset = info->var.bits_per_pixel
92                                                         * 2 / 3;
93                         info->var.red.length = info->var.bits_per_pixel / 3;
94                         info->var.red.msb_right = 0;
95                         info->var.green.offset = info->var.bits_per_pixel / 3;
96                         info->var.green.length = info->var.bits_per_pixel / 3;
97                         info->var.green.msb_right = 0;
98                         info->var.blue.offset = 0;
99                         info->var.blue.length = info->var.bits_per_pixel / 3;
100                         info->var.blue.msb_right = 0;
101                 }
102
103                 info->fix.visual = FB_VISUAL_TRUECOLOR;
104                 info->fix.line_length = info->var.bits_per_pixel > 16 ?
105                                         info->var.xres_virtual << 2 :
106                                         info->var.xres_virtual << 1;
107         }
108
109         for (i = 0; i < 8; i++) {
110                 if (bpp_values[i] == info->var.bits_per_pixel) {
111                         reg_bpp = i;
112                         continue;
113                 }
114         }
115
116         control0 = readl(fbi->regbase) & ~0xf;
117         writel(0, fbi->regbase);
118         while (readl(fbi->regbase + 0x38) & 0x10)
119                 /* wait */;
120         writel((((info->var.hsync_len - 1) & 0x3f) << 26)
121                 | ((info->var.left_margin & 0xff) << 18)
122                 | (((info->var.xres - 1) & 0x3ff) << 8)
123                 | (info->var.right_margin & 0xff), fbi->regbase + 0x4);
124         writel((((info->var.vsync_len - 1) & 0x3f) << 26)
125                 | ((info->var.upper_margin & 0xff) << 18)
126                 | (((info->var.yres - 1) & 0x3ff) << 8)
127                 | (info->var.lower_margin & 0xff), fbi->regbase + 0x8);
128         writel((((info->var.yres - 1) & 0x400) << 2)
129                 | ((info->var.xres - 1) & 0x400), fbi->regbase + 0x10);
130         writel(0x80000000, fbi->regbase + 0x20);
131         writel(control0 | (reg_bpp << 1) | 0x100, fbi->regbase);
132
133         return 0;
134 }
135
136 static inline u_int chan_to_field(u_int chan, struct fb_bitfield *bf)
137 {
138         chan &= 0xffff;
139         chan >>= 16 - bf->length;
140         return chan << bf->offset;
141 }
142
143 static int vt8500lcd_setcolreg(unsigned regno, unsigned red, unsigned green,
144                            unsigned blue, unsigned transp,
145                            struct fb_info *info) {
146         struct vt8500lcd_info *fbi = to_vt8500lcd_info(info);
147         int ret = 1;
148         unsigned int val;
149         if (regno >= 256)
150                 return -EINVAL;
151
152         if (info->var.grayscale)
153                 red = green = blue =
154                         (19595 * red + 38470 * green + 7471 * blue) >> 16;
155
156         switch (fbi->fb.fix.visual) {
157         case FB_VISUAL_TRUECOLOR:
158                 if (regno < 16) {
159                         u32 *pal = fbi->fb.pseudo_palette;
160
161                         val  = chan_to_field(red, &fbi->fb.var.red);
162                         val |= chan_to_field(green, &fbi->fb.var.green);
163                         val |= chan_to_field(blue, &fbi->fb.var.blue);
164
165                         pal[regno] = val;
166                         ret = 0;
167                 }
168                 break;
169
170         case FB_VISUAL_STATIC_PSEUDOCOLOR:
171         case FB_VISUAL_PSEUDOCOLOR:
172                 writew((red & 0xf800)
173                       | ((green >> 5) & 0x7e0)
174                       | ((blue >> 11) & 0x1f),
175                        fbi->palette_cpu + sizeof(u16) * regno);
176                 break;
177         }
178
179         return ret;
180 }
181
182 static int vt8500lcd_ioctl(struct fb_info *info, unsigned int cmd,
183                          unsigned long arg)
184 {
185         int ret = 0;
186         struct vt8500lcd_info *fbi = to_vt8500lcd_info(info);
187
188         if (cmd == FBIO_WAITFORVSYNC) {
189                 /* Unmask End of Frame interrupt */
190                 writel(0xffffffff ^ (1 << 3), fbi->regbase + 0x3c);
191                 ret = wait_event_interruptible_timeout(fbi->wait,
192                         readl(fbi->regbase + 0x38) & (1 << 3), HZ / 10);
193                 /* Mask back to reduce unwanted interrupt traffic */
194                 writel(0xffffffff, fbi->regbase + 0x3c);
195                 if (ret < 0)
196                         return ret;
197                 if (ret == 0)
198                         return -ETIMEDOUT;
199         }
200
201         return ret;
202 }
203
204 static int vt8500lcd_pan_display(struct fb_var_screeninfo *var,
205                                 struct fb_info *info)
206 {
207         unsigned pixlen = info->fix.line_length / info->var.xres_virtual;
208         unsigned off = pixlen * var->xoffset
209                       + info->fix.line_length * var->yoffset;
210         struct vt8500lcd_info *fbi = to_vt8500lcd_info(info);
211
212         writel((1 << 31)
213              | (((info->var.xres_virtual - info->var.xres) * pixlen / 4) << 20)
214              | (off >> 2), fbi->regbase + 0x20);
215         return 0;
216 }
217
218 /*
219  * vt8500lcd_blank():
220  *      Blank the display by setting all palette values to zero.  Note,
221  *      True Color modes do not really use the palette, so this will not
222  *      blank the display in all modes.
223  */
224 static int vt8500lcd_blank(int blank, struct fb_info *info)
225 {
226         int i;
227
228         switch (blank) {
229         case FB_BLANK_POWERDOWN:
230         case FB_BLANK_VSYNC_SUSPEND:
231         case FB_BLANK_HSYNC_SUSPEND:
232         case FB_BLANK_NORMAL:
233                 if (info->fix.visual == FB_VISUAL_PSEUDOCOLOR ||
234                     info->fix.visual == FB_VISUAL_STATIC_PSEUDOCOLOR)
235                         for (i = 0; i < 256; i++)
236                                 vt8500lcd_setcolreg(i, 0, 0, 0, 0, info);
237         case FB_BLANK_UNBLANK:
238                 if (info->fix.visual == FB_VISUAL_PSEUDOCOLOR ||
239                     info->fix.visual == FB_VISUAL_STATIC_PSEUDOCOLOR)
240                         fb_set_cmap(&info->cmap, info);
241         }
242         return 0;
243 }
244
245 static struct fb_ops vt8500lcd_ops = {
246         .owner          = THIS_MODULE,
247         .fb_set_par     = vt8500lcd_set_par,
248         .fb_setcolreg   = vt8500lcd_setcolreg,
249         .fb_fillrect    = wmt_ge_fillrect,
250         .fb_copyarea    = wmt_ge_copyarea,
251         .fb_imageblit   = sys_imageblit,
252         .fb_sync        = wmt_ge_sync,
253         .fb_ioctl       = vt8500lcd_ioctl,
254         .fb_pan_display = vt8500lcd_pan_display,
255         .fb_blank       = vt8500lcd_blank,
256 };
257
258 static irqreturn_t vt8500lcd_handle_irq(int irq, void *dev_id)
259 {
260         struct vt8500lcd_info *fbi = dev_id;
261
262         if (readl(fbi->regbase + 0x38) & (1 << 3))
263                 wake_up_interruptible(&fbi->wait);
264
265         writel(0xffffffff, fbi->regbase + 0x38);
266         return IRQ_HANDLED;
267 }
268
269 static int __devinit vt8500lcd_probe(struct platform_device *pdev)
270 {
271         struct vt8500lcd_info *fbi;
272         struct resource *res;
273         struct vt8500fb_platform_data *pdata = pdev->dev.platform_data;
274         void *addr;
275         int irq, ret;
276
277         ret = -ENOMEM;
278         fbi = NULL;
279
280         fbi = kzalloc(sizeof(struct vt8500lcd_info) + sizeof(u32) * 16,
281                                                         GFP_KERNEL);
282         if (!fbi) {
283                 dev_err(&pdev->dev, "Failed to initialize framebuffer device\n");
284                 ret = -ENOMEM;
285                 goto failed;
286         }
287
288         strcpy(fbi->fb.fix.id, "VT8500 LCD");
289
290         fbi->fb.fix.type        = FB_TYPE_PACKED_PIXELS;
291         fbi->fb.fix.xpanstep    = 0;
292         fbi->fb.fix.ypanstep    = 1;
293         fbi->fb.fix.ywrapstep   = 0;
294         fbi->fb.fix.accel       = FB_ACCEL_NONE;
295
296         fbi->fb.var.nonstd      = 0;
297         fbi->fb.var.activate    = FB_ACTIVATE_NOW;
298         fbi->fb.var.height      = -1;
299         fbi->fb.var.width       = -1;
300         fbi->fb.var.vmode       = FB_VMODE_NONINTERLACED;
301
302         fbi->fb.fbops           = &vt8500lcd_ops;
303         fbi->fb.flags           = FBINFO_DEFAULT
304                                 | FBINFO_HWACCEL_COPYAREA
305                                 | FBINFO_HWACCEL_FILLRECT
306                                 | FBINFO_HWACCEL_YPAN
307                                 | FBINFO_VIRTFB
308                                 | FBINFO_PARTIAL_PAN_OK;
309         fbi->fb.node            = -1;
310
311         addr = fbi;
312         addr = addr + sizeof(struct vt8500lcd_info);
313         fbi->fb.pseudo_palette  = addr;
314
315         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
316         if (res == NULL) {
317                 dev_err(&pdev->dev, "no I/O memory resource defined\n");
318                 ret = -ENODEV;
319                 goto failed_fbi;
320         }
321
322         res = request_mem_region(res->start, resource_size(res), "vt8500lcd");
323         if (res == NULL) {
324                 dev_err(&pdev->dev, "failed to request I/O memory\n");
325                 ret = -EBUSY;
326                 goto failed_fbi;
327         }
328
329         fbi->regbase = ioremap(res->start, resource_size(res));
330         if (fbi->regbase == NULL) {
331                 dev_err(&pdev->dev, "failed to map I/O memory\n");
332                 ret = -EBUSY;
333                 goto failed_free_res;
334         }
335
336         fbi->fb.fix.smem_start  = pdata->video_mem_phys;
337         fbi->fb.fix.smem_len    = pdata->video_mem_len;
338         fbi->fb.screen_base     = pdata->video_mem_virt;
339
340         fbi->palette_size       = PAGE_ALIGN(512);
341         fbi->palette_cpu        = dma_alloc_coherent(&pdev->dev,
342                                                      fbi->palette_size,
343                                                      &fbi->palette_phys,
344                                                      GFP_KERNEL);
345         if (fbi->palette_cpu == NULL) {
346                 dev_err(&pdev->dev, "Failed to allocate palette buffer\n");
347                 ret = -ENOMEM;
348                 goto failed_free_io;
349         }
350
351         irq = platform_get_irq(pdev, 0);
352         if (irq < 0) {
353                 dev_err(&pdev->dev, "no IRQ defined\n");
354                 ret = -ENODEV;
355                 goto failed_free_palette;
356         }
357
358         ret = request_irq(irq, vt8500lcd_handle_irq, 0, "LCD", fbi);
359         if (ret) {
360                 dev_err(&pdev->dev, "request_irq failed: %d\n", ret);
361                 ret = -EBUSY;
362                 goto failed_free_palette;
363         }
364
365         init_waitqueue_head(&fbi->wait);
366
367         if (fb_alloc_cmap(&fbi->fb.cmap, 256, 0) < 0) {
368                 dev_err(&pdev->dev, "Failed to allocate color map\n");
369                 ret = -ENOMEM;
370                 goto failed_free_irq;
371         }
372
373         fb_videomode_to_var(&fbi->fb.var, &pdata->mode);
374         fbi->fb.var.bits_per_pixel      = pdata->bpp;
375         fbi->fb.var.xres_virtual        = pdata->xres_virtual;
376         fbi->fb.var.yres_virtual        = pdata->yres_virtual;
377
378         ret = vt8500lcd_set_par(&fbi->fb);
379         if (ret) {
380                 dev_err(&pdev->dev, "Failed to set parameters\n");
381                 goto failed_free_cmap;
382         }
383
384         writel(fbi->fb.fix.smem_start >> 22, fbi->regbase + 0x1c);
385         writel((fbi->palette_phys & 0xfffffe00) | 1, fbi->regbase + 0x18);
386
387         platform_set_drvdata(pdev, fbi);
388
389         ret = register_framebuffer(&fbi->fb);
390         if (ret < 0) {
391                 dev_err(&pdev->dev,
392                         "Failed to register framebuffer device: %d\n", ret);
393                 goto failed_free_cmap;
394         }
395
396         /*
397          * Ok, now enable the LCD controller
398          */
399         writel(readl(fbi->regbase) | 1, fbi->regbase);
400
401         return 0;
402
403 failed_free_cmap:
404         if (fbi->fb.cmap.len)
405                 fb_dealloc_cmap(&fbi->fb.cmap);
406 failed_free_irq:
407         free_irq(irq, fbi);
408 failed_free_palette:
409         dma_free_coherent(&pdev->dev, fbi->palette_size,
410                           fbi->palette_cpu, fbi->palette_phys);
411 failed_free_io:
412         iounmap(fbi->regbase);
413 failed_free_res:
414         release_mem_region(res->start, resource_size(res));
415 failed_fbi:
416         platform_set_drvdata(pdev, NULL);
417         kfree(fbi);
418 failed:
419         return ret;
420 }
421
422 static int __devexit vt8500lcd_remove(struct platform_device *pdev)
423 {
424         struct vt8500lcd_info *fbi = platform_get_drvdata(pdev);
425         struct resource *res;
426         int irq;
427
428         unregister_framebuffer(&fbi->fb);
429
430         writel(0, fbi->regbase);
431
432         if (fbi->fb.cmap.len)
433                 fb_dealloc_cmap(&fbi->fb.cmap);
434
435         irq = platform_get_irq(pdev, 0);
436         free_irq(irq, fbi);
437
438         dma_free_coherent(&pdev->dev, fbi->palette_size,
439                           fbi->palette_cpu, fbi->palette_phys);
440
441         iounmap(fbi->regbase);
442
443         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
444         release_mem_region(res->start, resource_size(res));
445
446         kfree(fbi);
447
448         return 0;
449 }
450
451 static struct platform_driver vt8500lcd_driver = {
452         .probe          = vt8500lcd_probe,
453         .remove         = __devexit_p(vt8500lcd_remove),
454         .driver         = {
455                 .owner  = THIS_MODULE,
456                 .name   = "vt8500-lcd",
457         },
458 };
459
460 static int __init vt8500lcd_init(void)
461 {
462         return platform_driver_register(&vt8500lcd_driver);
463 }
464
465 static void __exit vt8500lcd_exit(void)
466 {
467         platform_driver_unregister(&vt8500lcd_driver);
468 }
469
470 module_init(vt8500lcd_init);
471 module_exit(vt8500lcd_exit);
472
473 MODULE_AUTHOR("Alexey Charkov <alchark@gmail.com>");
474 MODULE_DESCRIPTION("LCD controller driver for VIA VT8500");
475 MODULE_LICENSE("GPL");