linux/drivers/video/fbdev/vt8500lcdfb.c
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   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
  47static 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        }
 119
 120        control0 = readl(fbi->regbase) & ~0xf;
 121        writel(0, fbi->regbase);
 122        while (readl(fbi->regbase + 0x38) & 0x10)
 123                /* wait */;
 124        writel((((info->var.hsync_len - 1) & 0x3f) << 26)
 125                | ((info->var.left_margin & 0xff) << 18)
 126                | (((info->var.xres - 1) & 0x3ff) << 8)
 127                | (info->var.right_margin & 0xff), fbi->regbase + 0x4);
 128        writel((((info->var.vsync_len - 1) & 0x3f) << 26)
 129                | ((info->var.upper_margin & 0xff) << 18)
 130                | (((info->var.yres - 1) & 0x3ff) << 8)
 131                | (info->var.lower_margin & 0xff), fbi->regbase + 0x8);
 132        writel((((info->var.yres - 1) & 0x400) << 2)
 133                | ((info->var.xres - 1) & 0x400), fbi->regbase + 0x10);
 134        writel(0x80000000, fbi->regbase + 0x20);
 135        writel(control0 | (reg_bpp << 1) | 0x100, fbi->regbase);
 136
 137        return 0;
 138}
 139
 140static inline u_int chan_to_field(u_int chan, struct fb_bitfield *bf)
 141{
 142        chan &= 0xffff;
 143        chan >>= 16 - bf->length;
 144        return chan << bf->offset;
 145}
 146
 147static int vt8500lcd_setcolreg(unsigned regno, unsigned red, unsigned green,
 148                           unsigned blue, unsigned transp,
 149                           struct fb_info *info) {
 150        struct vt8500lcd_info *fbi = to_vt8500lcd_info(info);
 151        int ret = 1;
 152        unsigned int val;
 153        if (regno >= 256)
 154                return -EINVAL;
 155
 156        if (info->var.grayscale)
 157                red = green = blue =
 158                        (19595 * red + 38470 * green + 7471 * blue) >> 16;
 159
 160        switch (fbi->fb.fix.visual) {
 161        case FB_VISUAL_TRUECOLOR:
 162                if (regno < 16) {
 163                        u32 *pal = fbi->fb.pseudo_palette;
 164
 165                        val  = chan_to_field(red, &fbi->fb.var.red);
 166                        val |= chan_to_field(green, &fbi->fb.var.green);
 167                        val |= chan_to_field(blue, &fbi->fb.var.blue);
 168
 169                        pal[regno] = val;
 170                        ret = 0;
 171                }
 172                break;
 173
 174        case FB_VISUAL_STATIC_PSEUDOCOLOR:
 175        case FB_VISUAL_PSEUDOCOLOR:
 176                writew((red & 0xf800)
 177                      | ((green >> 5) & 0x7e0)
 178                      | ((blue >> 11) & 0x1f),
 179                       fbi->palette_cpu + sizeof(u16) * regno);
 180                break;
 181        }
 182
 183        return ret;
 184}
 185
 186static int vt8500lcd_ioctl(struct fb_info *info, unsigned int cmd,
 187                         unsigned long arg)
 188{
 189        int ret = 0;
 190        struct vt8500lcd_info *fbi = to_vt8500lcd_info(info);
 191
 192        if (cmd == FBIO_WAITFORVSYNC) {
 193                /* Unmask End of Frame interrupt */
 194                writel(0xffffffff ^ (1 << 3), fbi->regbase + 0x3c);
 195                ret = wait_event_interruptible_timeout(fbi->wait,
 196                        readl(fbi->regbase + 0x38) & (1 << 3), HZ / 10);
 197                /* Mask back to reduce unwanted interrupt traffic */
 198                writel(0xffffffff, fbi->regbase + 0x3c);
 199                if (ret < 0)
 200                        return ret;
 201                if (ret == 0)
 202                        return -ETIMEDOUT;
 203        }
 204
 205        return ret;
 206}
 207
 208static int vt8500lcd_pan_display(struct fb_var_screeninfo *var,
 209                                struct fb_info *info)
 210{
 211        unsigned pixlen = info->fix.line_length / info->var.xres_virtual;
 212        unsigned off = pixlen * var->xoffset
 213                      + info->fix.line_length * var->yoffset;
 214        struct vt8500lcd_info *fbi = to_vt8500lcd_info(info);
 215
 216        writel((1 << 31)
 217             | (((info->var.xres_virtual - info->var.xres) * pixlen / 4) << 20)
 218             | (off >> 2), fbi->regbase + 0x20);
 219        return 0;
 220}
 221
 222/*
 223 * vt8500lcd_blank():
 224 *      Blank the display by setting all palette values to zero.  Note,
 225 *      True Color modes do not really use the palette, so this will not
 226 *      blank the display in all modes.
 227 */
 228static int vt8500lcd_blank(int blank, struct fb_info *info)
 229{
 230        int i;
 231
 232        switch (blank) {
 233        case FB_BLANK_POWERDOWN:
 234        case FB_BLANK_VSYNC_SUSPEND:
 235        case FB_BLANK_HSYNC_SUSPEND:
 236        case FB_BLANK_NORMAL:
 237                if (info->fix.visual == FB_VISUAL_PSEUDOCOLOR ||
 238                    info->fix.visual == FB_VISUAL_STATIC_PSEUDOCOLOR)
 239                        for (i = 0; i < 256; i++)
 240                                vt8500lcd_setcolreg(i, 0, 0, 0, 0, info);
 241        case FB_BLANK_UNBLANK:
 242                if (info->fix.visual == FB_VISUAL_PSEUDOCOLOR ||
 243                    info->fix.visual == FB_VISUAL_STATIC_PSEUDOCOLOR)
 244                        fb_set_cmap(&info->cmap, info);
 245        }
 246        return 0;
 247}
 248
 249static struct fb_ops vt8500lcd_ops = {
 250        .owner          = THIS_MODULE,
 251        .fb_set_par     = vt8500lcd_set_par,
 252        .fb_setcolreg   = vt8500lcd_setcolreg,
 253        .fb_fillrect    = wmt_ge_fillrect,
 254        .fb_copyarea    = wmt_ge_copyarea,
 255        .fb_imageblit   = sys_imageblit,
 256        .fb_sync        = wmt_ge_sync,
 257        .fb_ioctl       = vt8500lcd_ioctl,
 258        .fb_pan_display = vt8500lcd_pan_display,
 259        .fb_blank       = vt8500lcd_blank,
 260};
 261
 262static irqreturn_t vt8500lcd_handle_irq(int irq, void *dev_id)
 263{
 264        struct vt8500lcd_info *fbi = dev_id;
 265
 266        if (readl(fbi->regbase + 0x38) & (1 << 3))
 267                wake_up_interruptible(&fbi->wait);
 268
 269        writel(0xffffffff, fbi->regbase + 0x38);
 270        return IRQ_HANDLED;
 271}
 272
 273static int vt8500lcd_probe(struct platform_device *pdev)
 274{
 275        struct vt8500lcd_info *fbi;
 276        struct resource *res;
 277        struct display_timings *disp_timing;
 278        void *addr;
 279        int irq, ret;
 280
 281        struct fb_videomode     of_mode;
 282        u32                     bpp;
 283        dma_addr_t fb_mem_phys;
 284        unsigned long fb_mem_len;
 285        void *fb_mem_virt;
 286
 287        ret = -ENOMEM;
 288        fbi = NULL;
 289
 290        fbi = devm_kzalloc(&pdev->dev, sizeof(struct vt8500lcd_info)
 291                        + sizeof(u32) * 16, GFP_KERNEL);
 292        if (!fbi) {
 293                dev_err(&pdev->dev, "Failed to initialize framebuffer device\n");
 294                return -ENOMEM;
 295        }
 296
 297        strcpy(fbi->fb.fix.id, "VT8500 LCD");
 298
 299        fbi->fb.fix.type        = FB_TYPE_PACKED_PIXELS;
 300        fbi->fb.fix.xpanstep    = 0;
 301        fbi->fb.fix.ypanstep    = 1;
 302        fbi->fb.fix.ywrapstep   = 0;
 303        fbi->fb.fix.accel       = FB_ACCEL_NONE;
 304
 305        fbi->fb.var.nonstd      = 0;
 306        fbi->fb.var.activate    = FB_ACTIVATE_NOW;
 307        fbi->fb.var.height      = -1;
 308        fbi->fb.var.width       = -1;
 309        fbi->fb.var.vmode       = FB_VMODE_NONINTERLACED;
 310
 311        fbi->fb.fbops           = &vt8500lcd_ops;
 312        fbi->fb.flags           = FBINFO_DEFAULT
 313                                | FBINFO_HWACCEL_COPYAREA
 314                                | FBINFO_HWACCEL_FILLRECT
 315                                | FBINFO_HWACCEL_YPAN
 316                                | FBINFO_VIRTFB
 317                                | FBINFO_PARTIAL_PAN_OK;
 318        fbi->fb.node            = -1;
 319
 320        addr = fbi;
 321        addr = addr + sizeof(struct vt8500lcd_info);
 322        fbi->fb.pseudo_palette  = addr;
 323
 324        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 325        if (res == NULL) {
 326                dev_err(&pdev->dev, "no I/O memory resource defined\n");
 327                return -ENODEV;
 328        }
 329
 330        res = request_mem_region(res->start, resource_size(res), "vt8500lcd");
 331        if (res == NULL) {
 332                dev_err(&pdev->dev, "failed to request I/O memory\n");
 333                return -EBUSY;
 334        }
 335
 336        fbi->regbase = ioremap(res->start, resource_size(res));
 337        if (fbi->regbase == NULL) {
 338                dev_err(&pdev->dev, "failed to map I/O memory\n");
 339                ret = -EBUSY;
 340                goto failed_free_res;
 341        }
 342
 343        disp_timing = of_get_display_timings(pdev->dev.of_node);
 344        if (!disp_timing) {
 345                ret = -EINVAL;
 346                goto failed_free_io;
 347        }
 348
 349        ret = of_get_fb_videomode(pdev->dev.of_node, &of_mode,
 350                                                        OF_USE_NATIVE_MODE);
 351        if (ret)
 352                goto failed_free_io;
 353
 354        ret = of_property_read_u32(pdev->dev.of_node, "bits-per-pixel", &bpp);
 355        if (ret)
 356                goto failed_free_io;
 357
 358        /* try allocating the framebuffer */
 359        fb_mem_len = of_mode.xres * of_mode.yres * 2 * (bpp / 8);
 360        fb_mem_virt = dma_alloc_coherent(&pdev->dev, fb_mem_len, &fb_mem_phys,
 361                                GFP_KERNEL);
 362        if (!fb_mem_virt) {
 363                pr_err("%s: Failed to allocate framebuffer\n", __func__);
 364                ret = -ENOMEM;
 365                goto failed_free_io;
 366        }
 367
 368        fbi->fb.fix.smem_start  = fb_mem_phys;
 369        fbi->fb.fix.smem_len    = fb_mem_len;
 370        fbi->fb.screen_base     = fb_mem_virt;
 371
 372        fbi->palette_size       = PAGE_ALIGN(512);
 373        fbi->palette_cpu        = dma_alloc_coherent(&pdev->dev,
 374                                                     fbi->palette_size,
 375                                                     &fbi->palette_phys,
 376                                                     GFP_KERNEL);
 377        if (fbi->palette_cpu == NULL) {
 378                dev_err(&pdev->dev, "Failed to allocate palette buffer\n");
 379                ret = -ENOMEM;
 380                goto failed_free_io;
 381        }
 382
 383        irq = platform_get_irq(pdev, 0);
 384        if (irq < 0) {
 385                dev_err(&pdev->dev, "no IRQ defined\n");
 386                ret = -ENODEV;
 387                goto failed_free_palette;
 388        }
 389
 390        ret = request_irq(irq, vt8500lcd_handle_irq, 0, "LCD", fbi);
 391        if (ret) {
 392                dev_err(&pdev->dev, "request_irq failed: %d\n", ret);
 393                ret = -EBUSY;
 394                goto failed_free_palette;
 395        }
 396
 397        init_waitqueue_head(&fbi->wait);
 398
 399        if (fb_alloc_cmap(&fbi->fb.cmap, 256, 0) < 0) {
 400                dev_err(&pdev->dev, "Failed to allocate color map\n");
 401                ret = -ENOMEM;
 402                goto failed_free_irq;
 403        }
 404
 405        fb_videomode_to_var(&fbi->fb.var, &of_mode);
 406
 407        fbi->fb.var.xres_virtual        = of_mode.xres;
 408        fbi->fb.var.yres_virtual        = of_mode.yres * 2;
 409        fbi->fb.var.bits_per_pixel      = bpp;
 410
 411        ret = vt8500lcd_set_par(&fbi->fb);
 412        if (ret) {
 413                dev_err(&pdev->dev, "Failed to set parameters\n");
 414                goto failed_free_cmap;
 415        }
 416
 417        writel(fbi->fb.fix.smem_start >> 22, fbi->regbase + 0x1c);
 418        writel((fbi->palette_phys & 0xfffffe00) | 1, fbi->regbase + 0x18);
 419
 420        platform_set_drvdata(pdev, fbi);
 421
 422        ret = register_framebuffer(&fbi->fb);
 423        if (ret < 0) {
 424                dev_err(&pdev->dev,
 425                        "Failed to register framebuffer device: %d\n", ret);
 426                goto failed_free_cmap;
 427        }
 428
 429        /*
 430         * Ok, now enable the LCD controller
 431         */
 432        writel(readl(fbi->regbase) | 1, fbi->regbase);
 433
 434        return 0;
 435
 436failed_free_cmap:
 437        if (fbi->fb.cmap.len)
 438                fb_dealloc_cmap(&fbi->fb.cmap);
 439failed_free_irq:
 440        free_irq(irq, fbi);
 441failed_free_palette:
 442        dma_free_coherent(&pdev->dev, fbi->palette_size,
 443                          fbi->palette_cpu, fbi->palette_phys);
 444failed_free_io:
 445        iounmap(fbi->regbase);
 446failed_free_res:
 447        release_mem_region(res->start, resource_size(res));
 448        return ret;
 449}
 450
 451static int vt8500lcd_remove(struct platform_device *pdev)
 452{
 453        struct vt8500lcd_info *fbi = platform_get_drvdata(pdev);
 454        struct resource *res;
 455        int irq;
 456
 457        unregister_framebuffer(&fbi->fb);
 458
 459        writel(0, fbi->regbase);
 460
 461        if (fbi->fb.cmap.len)
 462                fb_dealloc_cmap(&fbi->fb.cmap);
 463
 464        irq = platform_get_irq(pdev, 0);
 465        free_irq(irq, fbi);
 466
 467        dma_free_coherent(&pdev->dev, fbi->palette_size,
 468                          fbi->palette_cpu, fbi->palette_phys);
 469
 470        iounmap(fbi->regbase);
 471
 472        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 473        release_mem_region(res->start, resource_size(res));
 474
 475        return 0;
 476}
 477
 478static const struct of_device_id via_dt_ids[] = {
 479        { .compatible = "via,vt8500-fb", },
 480        {}
 481};
 482
 483static struct platform_driver vt8500lcd_driver = {
 484        .probe          = vt8500lcd_probe,
 485        .remove         = vt8500lcd_remove,
 486        .driver         = {
 487                .name   = "vt8500-lcd",
 488                .of_match_table = of_match_ptr(via_dt_ids),
 489        },
 490};
 491
 492module_platform_driver(vt8500lcd_driver);
 493
 494MODULE_AUTHOR("Alexey Charkov <alchark@gmail.com>");
 495MODULE_DESCRIPTION("LCD controller driver for VIA VT8500");
 496MODULE_LICENSE("GPL v2");
 497MODULE_DEVICE_TABLE(of, via_dt_ids);
 498
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