linux/drivers/video/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                        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
 142static 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
 149static 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
 188static 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
 210static 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 */
 230static 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
 251static 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
 264static 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
 275static 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
 438failed_free_cmap:
 439        if (fbi->fb.cmap.len)
 440                fb_dealloc_cmap(&fbi->fb.cmap);
 441failed_free_irq:
 442        free_irq(irq, fbi);
 443failed_free_palette:
 444        dma_free_coherent(&pdev->dev, fbi->palette_size,
 445                          fbi->palette_cpu, fbi->palette_phys);
 446failed_free_io:
 447        iounmap(fbi->regbase);
 448failed_free_res:
 449        release_mem_region(res->start, resource_size(res));
 450failed_fbi:
 451        platform_set_drvdata(pdev, NULL);
 452        kfree(fbi);
 453failed:
 454        return ret;
 455}
 456
 457static 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
 486static const struct of_device_id via_dt_ids[] = {
 487        { .compatible = "via,vt8500-fb", },
 488        {}
 489};
 490
 491static 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
 501module_platform_driver(vt8500lcd_driver);
 502
 503MODULE_AUTHOR("Alexey Charkov <alchark@gmail.com>");
 504MODULE_DESCRIPTION("LCD controller driver for VIA VT8500");
 505MODULE_LICENSE("GPL v2");
 506MODULE_DEVICE_TABLE(of, via_dt_ids);
 507
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