drivers/video/fbdev/goldfishfb.c

   1 /*
   2  * Copyright (C) 2007 Google, Inc.
   3  * Copyright (C) 2012 Intel, Inc.
   4  *
   5  * This software is licensed under the terms of the GNU General Public
   6  * License version 2, as published by the Free Software Foundation, and
   7  * may be copied, distributed, and modified under those terms.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  */
  15
  16 #include <linux/module.h>
  17 #include <linux/kernel.h>
  18 #include <linux/dma-mapping.h>
  19 #include <linux/errno.h>
  20 #include <linux/string.h>
  21 #include <linux/slab.h>
  22 #include <linux/delay.h>
  23 #include <linux/mm.h>
  24 #include <linux/fb.h>
  25 #include <linux/init.h>
  26 #include <linux/interrupt.h>
  27 #include <linux/ioport.h>
  28 #include <linux/platform_device.h>
  29 #include <linux/acpi.h>
  30
  31 enum {
  32         FB_GET_WIDTH        = 0x00,
  33         FB_GET_HEIGHT       = 0x04,
  34         FB_INT_STATUS       = 0x08,
  35         FB_INT_ENABLE       = 0x0c,
  36         FB_SET_BASE         = 0x10,
  37         FB_SET_ROTATION     = 0x14,
  38         FB_SET_BLANK        = 0x18,
  39         FB_GET_PHYS_WIDTH   = 0x1c,
  40         FB_GET_PHYS_HEIGHT  = 0x20,
  41
  42         FB_INT_VSYNC             = 1U << 0,
  43         FB_INT_BASE_UPDATE_DONE  = 1U << 1
  44 };
  45
  46 struct goldfish_fb {
  47         void __iomem *reg_base;
  48         int irq;
  49         spinlock_t lock;
  50         wait_queue_head_t wait;
  51         int base_update_count;
  52         int rotation;
  53         struct fb_info fb;
  54         u32 cmap[16];
  55 };
  56
  57 static irqreturn_t goldfish_fb_interrupt(int irq, void *dev_id)
  58 {
  59         unsigned long irq_flags;
  60         struct goldfish_fb *fb = dev_id;
  61         u32 status;
  62
  63         spin_lock_irqsave(&fb->lock, irq_flags);
  64         status = readl(fb->reg_base + FB_INT_STATUS);
  65         if (status & FB_INT_BASE_UPDATE_DONE) {
  66                 fb->base_update_count++;
  67                 wake_up(&fb->wait);
  68         }
  69         spin_unlock_irqrestore(&fb->lock, irq_flags);
  70         return status ? IRQ_HANDLED : IRQ_NONE;
  71 }
  72
  73 static inline u32 convert_bitfield(int val, struct fb_bitfield *bf)
  74 {
  75         unsigned int mask = (1 << bf->length) - 1;
  76
  77         return (val >> (16 - bf->length) & mask) << bf->offset;
  78 }
  79
  80 static int
  81 goldfish_fb_setcolreg(unsigned int regno, unsigned int red, unsigned int green,
  82                  unsigned int blue, unsigned int transp, struct fb_info *info)
  83 {
  84         struct goldfish_fb *fb = container_of(info, struct goldfish_fb, fb);
  85
  86         if (regno < 16) {
  87                 fb->cmap[regno] = convert_bitfield(transp, &fb->fb.var.transp) |
  88                                   convert_bitfield(blue, &fb->fb.var.blue) |
  89                                   convert_bitfield(green, &fb->fb.var.green) |
  90                                   convert_bitfield(red, &fb->fb.var.red);
  91                 return 0;
  92         } else {
  93                 return 1;
  94         }
  95 }
  96
  97 static int goldfish_fb_check_var(struct fb_var_screeninfo *var,
  98                                                         struct fb_info *info)
  99 {
 100         if ((var->rotate & 1) != (info->var.rotate & 1)) {
 101                 if ((var->xres != info->var.yres) ||
 102                                 (var->yres != info->var.xres) ||
 103                                 (var->xres_virtual != info->var.yres) ||
 104                                 (var->yres_virtual > info->var.xres * 2) ||
 105                                 (var->yres_virtual < info->var.xres)) {
 106                         return -EINVAL;
 107                 }
 108         } else {
 109                 if ((var->xres != info->var.xres) ||
 110                    (var->yres != info->var.yres) ||
 111                    (var->xres_virtual != info->var.xres) ||
 112                    (var->yres_virtual > info->var.yres * 2) ||
 113                    (var->yres_virtual < info->var.yres)) {
 114                         return -EINVAL;
 115                 }
 116         }
 117         if ((var->xoffset != info->var.xoffset) ||
 118                         (var->bits_per_pixel != info->var.bits_per_pixel) ||
 119                         (var->grayscale != info->var.grayscale)) {
 120                 return -EINVAL;
 121         }
 122         return 0;
 123 }
 124
 125 static int goldfish_fb_set_par(struct fb_info *info)
 126 {
 127         struct goldfish_fb *fb = container_of(info, struct goldfish_fb, fb);
 128
 129         if (fb->rotation != fb->fb.var.rotate) {
 130                 info->fix.line_length = info->var.xres * 2;
 131                 fb->rotation = fb->fb.var.rotate;
 132                 writel(fb->rotation, fb->reg_base + FB_SET_ROTATION);
 133         }
 134         return 0;
 135 }
 136
 137
 138 static int goldfish_fb_pan_display(struct fb_var_screeninfo *var,
 139                                                         struct fb_info *info)
 140 {
 141         unsigned long irq_flags;
 142         int base_update_count;
 143         struct goldfish_fb *fb = container_of(info, struct goldfish_fb, fb);
 144
 145         spin_lock_irqsave(&fb->lock, irq_flags);
 146         base_update_count = fb->base_update_count;
 147         writel(fb->fb.fix.smem_start + fb->fb.var.xres * 2 * var->yoffset,
 148                                                 fb->reg_base + FB_SET_BASE);
 149         spin_unlock_irqrestore(&fb->lock, irq_flags);
 150         wait_event_timeout(fb->wait,
 151                         fb->base_update_count != base_update_count, HZ / 15);
 152         if (fb->base_update_count == base_update_count)
 153                 pr_err("%s: timeout waiting for base update\n", __func__);
 154         return 0;
 155 }
 156
 157 static int goldfish_fb_blank(int blank, struct fb_info *info)
 158 {
 159         struct goldfish_fb *fb = container_of(info, struct goldfish_fb, fb);
 160
 161         switch (blank) {
 162         case FB_BLANK_NORMAL:
 163                 writel(1, fb->reg_base + FB_SET_BLANK);
 164                 break;
 165         case FB_BLANK_UNBLANK:
 166                 writel(0, fb->reg_base + FB_SET_BLANK);
 167                 break;
 168         }
 169         return 0;
 170 }
 171
 172 static struct fb_ops goldfish_fb_ops = {
 173         .owner          = THIS_MODULE,
 174         .fb_check_var   = goldfish_fb_check_var,
 175         .fb_set_par     = goldfish_fb_set_par,
 176         .fb_setcolreg   = goldfish_fb_setcolreg,
 177         .fb_pan_display = goldfish_fb_pan_display,
 178         .fb_blank       = goldfish_fb_blank,
 179         .fb_fillrect    = cfb_fillrect,
 180         .fb_copyarea    = cfb_copyarea,
 181         .fb_imageblit   = cfb_imageblit,
 182 };
 183
 184
 185 static int goldfish_fb_probe(struct platform_device *pdev)
 186 {
 187         int ret;
 188         struct resource *r;
 189         struct goldfish_fb *fb;
 190         size_t framesize;
 191         u32 width, height;
 192         dma_addr_t fbpaddr;
 193
 194         fb = kzalloc(sizeof(*fb), GFP_KERNEL);
 195         if (fb == NULL) {
 196                 ret = -ENOMEM;
 197                 goto err_fb_alloc_failed;
 198         }
 199         spin_lock_init(&fb->lock);
 200         init_waitqueue_head(&fb->wait);
 201         platform_set_drvdata(pdev, fb);
 202
 203         r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 204         if (r == NULL) {
 205                 ret = -ENODEV;
 206                 goto err_no_io_base;
 207         }
 208         fb->reg_base = ioremap(r->start, PAGE_SIZE);
 209         if (fb->reg_base == NULL) {
 210                 ret = -ENOMEM;
 211                 goto err_no_io_base;
 212         }
 213
 214         fb->irq = platform_get_irq(pdev, 0);
 215         if (fb->irq <= 0) {
 216                 ret = -ENODEV;
 217                 goto err_no_irq;
 218         }
 219
 220         width = readl(fb->reg_base + FB_GET_WIDTH);
 221         height = readl(fb->reg_base + FB_GET_HEIGHT);
 222
 223         fb->fb.fbops            = &goldfish_fb_ops;
 224         fb->fb.flags            = FBINFO_FLAG_DEFAULT;
 225         fb->fb.pseudo_palette   = fb->cmap;
 226         fb->fb.fix.type         = FB_TYPE_PACKED_PIXELS;
 227         fb->fb.fix.visual = FB_VISUAL_TRUECOLOR;
 228         fb->fb.fix.line_length = width * 2;
 229         fb->fb.fix.accel        = FB_ACCEL_NONE;
 230         fb->fb.fix.ypanstep = 1;
 231
 232         fb->fb.var.xres         = width;
 233         fb->fb.var.yres         = height;
 234         fb->fb.var.xres_virtual = width;
 235         fb->fb.var.yres_virtual = height * 2;
 236         fb->fb.var.bits_per_pixel = 16;
 237         fb->fb.var.activate     = FB_ACTIVATE_NOW;
 238         fb->fb.var.height       = readl(fb->reg_base + FB_GET_PHYS_HEIGHT);
 239         fb->fb.var.width        = readl(fb->reg_base + FB_GET_PHYS_WIDTH);
 240         fb->fb.var.pixclock     = 0;
 241
 242         fb->fb.var.red.offset = 11;
 243         fb->fb.var.red.length = 5;
 244         fb->fb.var.green.offset = 5;
 245         fb->fb.var.green.length = 6;
 246         fb->fb.var.blue.offset = 0;
 247         fb->fb.var.blue.length = 5;
 248
 249         framesize = width * height * 2 * 2;
 250         fb->fb.screen_base = (char __force __iomem *)dma_alloc_coherent(
 251                                                 &pdev->dev, framesize,
 252                                                 &fbpaddr, GFP_KERNEL);
 253         pr_debug("allocating frame buffer %d * %d, got %p\n",
 254                                         width, height, fb->fb.screen_base);
 255         if (fb->fb.screen_base == NULL) {
 256                 ret = -ENOMEM;
 257                 goto err_alloc_screen_base_failed;
 258         }
 259         fb->fb.fix.smem_start = fbpaddr;
 260         fb->fb.fix.smem_len = framesize;
 261
 262         ret = fb_set_var(&fb->fb, &fb->fb.var);
 263         if (ret)
 264                 goto err_fb_set_var_failed;
 265
 266         ret = request_irq(fb->irq, goldfish_fb_interrupt, IRQF_SHARED,
 267                                                         pdev->name, fb);
 268         if (ret)
 269                 goto err_request_irq_failed;
 270
 271         writel(FB_INT_BASE_UPDATE_DONE, fb->reg_base + FB_INT_ENABLE);
 272         goldfish_fb_pan_display(&fb->fb.var, &fb->fb); /* updates base */
 273
 274         ret = register_framebuffer(&fb->fb);
 275         if (ret)
 276                 goto err_register_framebuffer_failed;
 277         return 0;
 278
 279 err_register_framebuffer_failed:
 280         free_irq(fb->irq, fb);
 281 err_request_irq_failed:
 282 err_fb_set_var_failed:
 283         dma_free_coherent(&pdev->dev, framesize,
 284                                 (void *)fb->fb.screen_base,
 285                                 fb->fb.fix.smem_start);
 286 err_alloc_screen_base_failed:
 287 err_no_irq:
 288         iounmap(fb->reg_base);
 289 err_no_io_base:
 290         kfree(fb);
 291 err_fb_alloc_failed:
 292         return ret;
 293 }
 294
 295 static int goldfish_fb_remove(struct platform_device *pdev)
 296 {
 297         size_t framesize;
 298         struct goldfish_fb *fb = platform_get_drvdata(pdev);
 299
 300         framesize = fb->fb.var.xres_virtual * fb->fb.var.yres_virtual * 2;
 301         unregister_framebuffer(&fb->fb);
 302         free_irq(fb->irq, fb);
 303
 304         dma_free_coherent(&pdev->dev, framesize, (void *)fb->fb.screen_base,
 305                                                 fb->fb.fix.smem_start);
 306         iounmap(fb->reg_base);
 307         kfree(fb);
 308         return 0;
 309 }
 310
 311 static const struct of_device_id goldfish_fb_of_match[] = {
 312         { .compatible = "google,goldfish-fb", },
 313         {},
 314 };
 315 MODULE_DEVICE_TABLE(of, goldfish_fb_of_match);
 316
 317 static const struct acpi_device_id goldfish_fb_acpi_match[] = {
 318         { "GFSH0004", 0 },
 319         { },
 320 };
 321 MODULE_DEVICE_TABLE(acpi, goldfish_fb_acpi_match);
 322
 323 static struct platform_driver goldfish_fb_driver = {
 324         .probe          = goldfish_fb_probe,
 325         .remove         = goldfish_fb_remove,
 326         .driver = {
 327                 .name = "goldfish_fb",
 328                 .of_match_table = goldfish_fb_of_match,
 329                 .acpi_match_table = ACPI_PTR(goldfish_fb_acpi_match),
 330         }
 331 };
 332
 333 module_platform_driver(goldfish_fb_driver);
 334
 335 MODULE_LICENSE("GPL v2");