drivers/video/clps711xfb.c

   1 /*
   2  *  linux/drivers/video/clps711xfb.c
   3  *
   4  *  Copyright (C) 2000-2001 Deep Blue Solutions Ltd.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  *
  20  *  Framebuffer driver for the CLPS7111 and EP7212 processors.
  21  */
  22 #include <linux/mm.h>
  23 #include <linux/module.h>
  24 #include <linux/kernel.h>
  25 #include <linux/seq_file.h>
  26 #include <linux/slab.h>
  27 #include <linux/fb.h>
  28 #include <linux/init.h>
  29 #include <linux/proc_fs.h>
  30 #include <linux/delay.h>
  31
  32 #include <mach/hardware.h>
  33 #include <asm/mach-types.h>
  34 #include <linux/uaccess.h>
  35
  36 #include <asm/hardware/clps7111.h>
  37 #include <mach/syspld.h>
  38
  39 struct fb_info  *cfb;
  40
  41 #define CMAP_MAX_SIZE   16
  42
  43 /*
  44  * LCD AC Prescale.  This comes from the LCD panel manufacturers specifications.
  45  * This determines how many clocks + 1 of CL1 before the M signal toggles.
  46  * The number of lines on the display must not be divisible by this number.
  47  */
  48 static unsigned int lcd_ac_prescale = 13;
  49
  50 /*
  51  *    Set a single color register. Return != 0 for invalid regno.
  52  */
  53 static int
  54 clps7111fb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
  55                      u_int transp, struct fb_info *info)
  56 {
  57         unsigned int level, mask, shift, pal;
  58
  59         if (regno >= (1 << info->var.bits_per_pixel))
  60                 return 1;
  61
  62         /* gray = 0.30*R + 0.58*G + 0.11*B */
  63         level = (red * 77 + green * 151 + blue * 28) >> 20;
  64
  65         /*
  66          * On an LCD, a high value is dark, while a low value is light.
  67          * So we invert the level.
  68          *
  69          * This isn't true on all machines, so we only do it on EDB7211.
  70          *  --rmk
  71          */
  72         if (machine_is_edb7211()) {
  73                 level = 15 - level;
  74         }
  75
  76         shift = 4 * (regno & 7);
  77         level <<= shift;
  78         mask  = 15 << shift;
  79         level &= mask;
  80
  81         regno = regno < 8 ? PALLSW : PALMSW;
  82
  83         pal = clps_readl(regno);
  84         pal = (pal & ~mask) | level;
  85         clps_writel(pal, regno);
  86
  87         return 0;
  88 }
  89
  90 /*
  91  * Validate the purposed mode.
  92  */
  93 static int
  94 clps7111fb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
  95 {
  96         var->transp.msb_right   = 0;
  97         var->transp.offset      = 0;
  98         var->transp.length      = 0;
  99         var->red.msb_right      = 0;
 100         var->red.offset         = 0;
 101         var->red.length         = var->bits_per_pixel;
 102         var->green              = var->red;
 103         var->blue               = var->red;
 104
 105         if (var->bits_per_pixel > 4)
 106                 return -EINVAL;
 107
 108         return 0;
 109 }
 110
 111 /*
 112  * Set the hardware state.
 113  */
 114 static int
 115 clps7111fb_set_par(struct fb_info *info)
 116 {
 117         unsigned int lcdcon, syscon, pixclock;
 118
 119         switch (info->var.bits_per_pixel) {
 120         case 1:
 121                 info->fix.visual = FB_VISUAL_MONO01;
 122                 break;
 123         case 2:
 124                 info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
 125                 break;
 126         case 4:
 127                 info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
 128                 break;
 129         }
 130
 131         info->fix.line_length = info->var.xres_virtual * info->var.bits_per_pixel / 8;
 132
 133         lcdcon = (info->var.xres_virtual * info->var.yres_virtual * info->var.bits_per_pixel) / 128 - 1;
 134         lcdcon |= ((info->var.xres_virtual / 16) - 1) << 13;
 135         lcdcon |= lcd_ac_prescale << 25;
 136
 137         /*
 138          * Calculate pixel prescale value from the pixclock.  This is:
 139          *  36.864MHz / pixclock_mhz - 1.
 140          * However, pixclock is in picoseconds, so this ends up being:
 141          *  36864000 * pixclock_ps / 10^12 - 1
 142          * and this will overflow the 32-bit math.  We perform this as
 143          * (9 * 4096000 == 36864000):
 144          *  pixclock_ps * 9 * (4096000 / 10^12) - 1
 145          */
 146         pixclock = 9 * info->var.pixclock / 244140 - 1;
 147         lcdcon |= pixclock << 19;
 148
 149         if (info->var.bits_per_pixel == 4)
 150                 lcdcon |= LCDCON_GSMD;
 151         if (info->var.bits_per_pixel >= 2)
 152                 lcdcon |= LCDCON_GSEN;
 153
 154         /*
 155          * LCDCON must only be changed while the LCD is disabled
 156          */
 157         syscon = clps_readl(SYSCON1);
 158         clps_writel(syscon & ~SYSCON1_LCDEN, SYSCON1);
 159         clps_writel(lcdcon, LCDCON);
 160         clps_writel(syscon | SYSCON1_LCDEN, SYSCON1);
 161         return 0;
 162 }
 163
 164 static int clps7111fb_blank(int blank, struct fb_info *info)
 165 {
 166         if (blank) {
 167                 if (machine_is_edb7211()) {
 168                         /* Turn off the LCD backlight. */
 169                         clps_writeb(clps_readb(PDDR) & ~EDB_PD3_LCDBL, PDDR);
 170
 171                         /* Power off the LCD DC-DC converter. */
 172                         clps_writeb(clps_readb(PDDR) & ~EDB_PD1_LCD_DC_DC_EN, PDDR);
 173
 174                         /* Delay for a little while (half a second). */
 175                         udelay(100);
 176
 177                         /* Power off the LCD panel. */
 178                         clps_writeb(clps_readb(PDDR) & ~EDB_PD2_LCDEN, PDDR);
 179
 180                         /* Power off the LCD controller. */
 181                         clps_writel(clps_readl(SYSCON1) & ~SYSCON1_LCDEN,
 182                                         SYSCON1);
 183                 }
 184         } else {
 185                 if (machine_is_edb7211()) {
 186                         /* Power up the LCD controller. */
 187                         clps_writel(clps_readl(SYSCON1) | SYSCON1_LCDEN,
 188                                         SYSCON1);
 189
 190                         /* Power up the LCD panel. */
 191                         clps_writeb(clps_readb(PDDR) | EDB_PD2_LCDEN, PDDR);
 192
 193                         /* Delay for a little while. */
 194                         udelay(100);
 195
 196                         /* Power up the LCD DC-DC converter. */
 197                         clps_writeb(clps_readb(PDDR) | EDB_PD1_LCD_DC_DC_EN,
 198                                         PDDR);
 199
 200                         /* Turn on the LCD backlight. */
 201                         clps_writeb(clps_readb(PDDR) | EDB_PD3_LCDBL, PDDR);
 202                 }
 203         }
 204         return 0;
 205 }
 206
 207 static struct fb_ops clps7111fb_ops = {
 208         .owner          = THIS_MODULE,
 209         .fb_check_var   = clps7111fb_check_var,
 210         .fb_set_par     = clps7111fb_set_par,
 211         .fb_setcolreg   = clps7111fb_setcolreg,
 212         .fb_blank       = clps7111fb_blank,
 213         .fb_fillrect    = cfb_fillrect,
 214         .fb_copyarea    = cfb_copyarea,
 215         .fb_imageblit   = cfb_imageblit,
 216 };
 217
 218 static int backlight_proc_show(struct seq_file *m, void *v)
 219 {
 220         if (machine_is_edb7211()) {
 221                 seq_printf(m, "%d\n",
 222                                 (clps_readb(PDDR) & EDB_PD3_LCDBL) ? 1 : 0);
 223         }
 224
 225         return 0;
 226 }
 227
 228 static int backlight_proc_open(struct inode *inode, struct file *file)
 229 {
 230         return single_open(file, backlight_proc_show, NULL);
 231 }
 232
 233 static ssize_t backlight_proc_write(struct file *file, const char *buffer,
 234                                     size_t count, loff_t *pos)
 235 {
 236         unsigned char char_value;
 237         int value;
 238
 239         if (count < 1) {
 240                 return -EINVAL;
 241         }
 242
 243         if (copy_from_user(&char_value, buffer, 1))
 244                 return -EFAULT;
 245
 246         value = char_value - '0';
 247
 248         if (machine_is_edb7211()) {
 249                 unsigned char port_d;
 250
 251                 port_d = clps_readb(PDDR);
 252
 253                 if (value) {
 254                         port_d |= EDB_PD3_LCDBL;
 255                 } else {
 256                         port_d &= ~EDB_PD3_LCDBL;
 257                 }
 258
 259                 clps_writeb(port_d, PDDR);
 260         }
 261
 262         return count;
 263 }
 264
 265 static const struct file_operations backlight_proc_fops = {
 266         .owner          = THIS_MODULE,
 267         .open           = backlight_proc_open,
 268         .read           = seq_read,
 269         .llseek         = seq_lseek,
 270         .release        = single_release,
 271         .write          = backlight_proc_write,
 272 };
 273
 274 static void __init clps711x_guess_lcd_params(struct fb_info *info)
 275 {
 276         unsigned int lcdcon, syscon, size;
 277         unsigned long phys_base = PAGE_OFFSET;
 278         void *virt_base = (void *)PAGE_OFFSET;
 279
 280         info->var.xres_virtual   = 640;
 281         info->var.yres_virtual   = 240;
 282         info->var.bits_per_pixel = 4;
 283         info->var.activate       = FB_ACTIVATE_NOW;
 284         info->var.height         = -1;
 285         info->var.width          = -1;
 286         info->var.pixclock       = 93006; /* 10.752MHz pixel clock */
 287
 288         /*
 289          * If the LCD controller is already running, decode the values
 290          * in LCDCON to xres/yres/bpp/pixclock/acprescale
 291          */
 292         syscon = clps_readl(SYSCON1);
 293         if (syscon & SYSCON1_LCDEN) {
 294                 lcdcon = clps_readl(LCDCON);
 295
 296                 /*
 297                  * Decode GSMD and GSEN bits to bits per pixel
 298                  */
 299                 switch (lcdcon & (LCDCON_GSMD | LCDCON_GSEN)) {
 300                 case LCDCON_GSMD | LCDCON_GSEN:
 301                         info->var.bits_per_pixel = 4;
 302                         break;
 303
 304                 case LCDCON_GSEN:
 305                         info->var.bits_per_pixel = 2;
 306                         break;
 307
 308                 default:
 309                         info->var.bits_per_pixel = 1;
 310                         break;
 311                 }
 312
 313                 /*
 314                  * Decode xres/yres
 315                  */
 316                 info->var.xres_virtual = (((lcdcon >> 13) & 0x3f) + 1) * 16;
 317                 info->var.yres_virtual = (((lcdcon & 0x1fff) + 1) * 128) /
 318                                           (info->var.xres_virtual *
 319                                            info->var.bits_per_pixel);
 320
 321                 /*
 322                  * Calculate pixclock
 323                  */
 324                 info->var.pixclock = (((lcdcon >> 19) & 0x3f) + 1) * 244140 / 9;
 325
 326                 /*
 327                  * Grab AC prescale
 328                  */
 329                 lcd_ac_prescale = (lcdcon >> 25) & 0x1f;
 330         }
 331
 332         info->var.xres = info->var.xres_virtual;
 333         info->var.yres = info->var.yres_virtual;
 334         info->var.grayscale = info->var.bits_per_pixel > 1;
 335
 336         size = info->var.xres * info->var.yres * info->var.bits_per_pixel / 8;
 337
 338         /*
 339          * Might be worth checking to see if we can use the on-board
 340          * RAM if size here...
 341          * CLPS7110 - no on-board SRAM
 342          * EP7212   - 38400 bytes
 343          */
 344         if (size <= 38400) {
 345                 printk(KERN_INFO "CLPS711xFB: could use on-board SRAM?\n");
 346         }
 347
 348         if ((syscon & SYSCON1_LCDEN) == 0) {
 349                 /*
 350                  * The display isn't running.  Ensure that
 351                  * the display memory is empty.
 352                  */
 353                 memset(virt_base, 0, size);
 354         }
 355
 356         info->screen_base    = virt_base;
 357         info->fix.smem_start = phys_base;
 358         info->fix.smem_len   = PAGE_ALIGN(size);
 359         info->fix.type       = FB_TYPE_PACKED_PIXELS;
 360 }
 361
 362 int __init clps711xfb_init(void)
 363 {
 364         int err = -ENOMEM;
 365
 366         if (fb_get_options("clps711xfb", NULL))
 367                 return -ENODEV;
 368
 369         cfb = kzalloc(sizeof(*cfb), GFP_KERNEL);
 370         if (!cfb)
 371                 goto out;
 372
 373         strcpy(cfb->fix.id, "clps711x");
 374
 375         cfb->fbops              = &clps7111fb_ops;
 376         cfb->flags              = FBINFO_DEFAULT;
 377
 378         clps711x_guess_lcd_params(cfb);
 379
 380         fb_alloc_cmap(&cfb->cmap, CMAP_MAX_SIZE, 0);
 381
 382         if (!proc_create("backlight", 0444, NULL, &backlight_proc_fops)) {
 383                 printk("Couldn't create the /proc entry for the backlight.\n");
 384                 return -EINVAL;
 385         }
 386
 387         /*
 388          * Power up the LCD
 389          */
 390         if (machine_is_p720t()) {
 391                 PLD_LCDEN = PLD_LCDEN_EN;
 392                 PLD_PWR |= (PLD_S4_ON|PLD_S3_ON|PLD_S2_ON|PLD_S1_ON);
 393         }
 394
 395         if (machine_is_edb7211()) {
 396                 /* Power up the LCD panel. */
 397                 clps_writeb(clps_readb(PDDR) | EDB_PD2_LCDEN, PDDR);
 398
 399                 /* Delay for a little while. */
 400                 udelay(100);
 401
 402                 /* Power up the LCD DC-DC converter. */
 403                 clps_writeb(clps_readb(PDDR) | EDB_PD1_LCD_DC_DC_EN, PDDR);
 404
 405                 /* Turn on the LCD backlight. */
 406                 clps_writeb(clps_readb(PDDR) | EDB_PD3_LCDBL, PDDR);
 407         }
 408
 409         err = register_framebuffer(cfb);
 410
 411 out:    return err;
 412 }
 413
 414 static void __exit clps711xfb_exit(void)
 415 {
 416         unregister_framebuffer(cfb);
 417         kfree(cfb);
 418
 419         /*
 420          * Power down the LCD
 421          */
 422         if (machine_is_p720t()) {
 423                 PLD_LCDEN = 0;
 424                 PLD_PWR &= ~(PLD_S4_ON|PLD_S3_ON|PLD_S2_ON|PLD_S1_ON);
 425         }
 426 }
 427
 428 module_init(clps711xfb_init);
 429 module_exit(clps711xfb_exit);
 430
 431 MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
 432 MODULE_DESCRIPTION("CLPS711x framebuffer driver");
 433 MODULE_LICENSE("GPL");