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/module.h>
  23 #include <linux/kernel.h>
  24 #include <linux/slab.h>
  25 #include <linux/fb.h>
  26 #include <linux/init.h>
  27 #include <linux/proc_fs.h>
  28 #include <linux/delay.h>
  29
  30 #include <asm/hardware.h>
  31 #include <asm/mach-types.h>
  32 #include <asm/uaccess.h>
  33
  34 #include <asm/hardware/clps7111.h>
  35 #include <asm/arch/syspld.h>
  36
  37 struct fb_info  *cfb;
  38
  39 #define CMAP_MAX_SIZE   16
  40
  41 /* The /proc entry for the backlight. */
  42 static struct proc_dir_entry *clps7111fb_backlight_proc_entry = NULL;
  43
  44 static int clps7111fb_proc_backlight_read(char *page, char **start, off_t off,
  45                 int count, int *eof, void *data);
  46 static int clps7111fb_proc_backlight_write(struct file *file,
  47                 const char *buffer, unsigned long count, void *data);
  48
  49 /*
  50  * LCD AC Prescale.  This comes from the LCD panel manufacturers specifications.
  51  * This determines how many clocks + 1 of CL1 before the M signal toggles.
  52  * The number of lines on the display must not be divisible by this number.
  53  */
  54 static unsigned int lcd_ac_prescale = 13;
  55
  56 /*
  57  *    Set a single color register. Return != 0 for invalid regno.
  58  */
  59 static int
  60 clps7111fb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
  61                      u_int transp, struct fb_info *info)
  62 {
  63         unsigned int level, mask, shift, pal;
  64
  65         if (regno >= (1 << info->var.bits_per_pixel))
  66                 return 1;
  67
  68         /* gray = 0.30*R + 0.58*G + 0.11*B */
  69         level = (red * 77 + green * 151 + blue * 28) >> 20;
  70
  71         /*
  72          * On an LCD, a high value is dark, while a low value is light.
  73          * So we invert the level.
  74          *
  75          * This isn't true on all machines, so we only do it on EDB7211.
  76          *  --rmk
  77          */
  78         if (machine_is_edb7211()) {
  79                 level = 15 - level;
  80         }
  81
  82         shift = 4 * (regno & 7);
  83         level <<= shift;
  84         mask  = 15 << shift;
  85         level &= mask;
  86
  87         regno = regno < 8 ? PALLSW : PALMSW;
  88
  89         pal = clps_readl(regno);
  90         pal = (pal & ~mask) | level;
  91         clps_writel(pal, regno);
  92
  93         return 0;
  94 }
  95
  96 /*
  97  * Validate the purposed mode.
  98  */
  99 static int
 100 clps7111fb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
 101 {
 102         var->transp.msb_right   = 0;
 103         var->transp.offset      = 0;
 104         var->transp.length      = 0;
 105         var->red.msb_right      = 0;
 106         var->red.offset         = 0;
 107         var->red.length         = var->bits_per_pixel;
 108         var->green              = var->red;
 109         var->blue               = var->red;
 110
 111         if (var->bits_per_pixel > 4)
 112                 return -EINVAL;
 113
 114         return 0;
 115 }
 116
 117 /*
 118  * Set the hardware state.
 119  */
 120 static int
 121 clps7111fb_set_par(struct fb_info *info)
 122 {
 123         unsigned int lcdcon, syscon, pixclock;
 124
 125         switch (info->var.bits_per_pixel) {
 126         case 1:
 127                 info->fix.visual = FB_VISUAL_MONO01;
 128                 break;
 129         case 2:
 130                 info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
 131                 break;
 132         case 4:
 133                 info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
 134                 break;
 135         }
 136
 137         info->fix.line_length = info->var.xres_virtual * info->var.bits_per_pixel / 8;
 138
 139         lcdcon = (info->var.xres_virtual * info->var.yres_virtual * info->var.bits_per_pixel) / 128 - 1;
 140         lcdcon |= ((info->var.xres_virtual / 16) - 1) << 13;
 141         lcdcon |= lcd_ac_prescale << 25;
 142
 143         /*
 144          * Calculate pixel prescale value from the pixclock.  This is:
 145          *  36.864MHz / pixclock_mhz - 1.
 146          * However, pixclock is in picoseconds, so this ends up being:
 147          *  36864000 * pixclock_ps / 10^12 - 1
 148          * and this will overflow the 32-bit math.  We perform this as
 149          * (9 * 4096000 == 36864000):
 150          *  pixclock_ps * 9 * (4096000 / 10^12) - 1
 151          */
 152         pixclock = 9 * info->var.pixclock / 244140 - 1;
 153         lcdcon |= pixclock << 19;
 154
 155         if (info->var.bits_per_pixel == 4)
 156                 lcdcon |= LCDCON_GSMD;
 157         if (info->var.bits_per_pixel >= 2)
 158                 lcdcon |= LCDCON_GSEN;
 159
 160         /*
 161          * LCDCON must only be changed while the LCD is disabled
 162          */
 163         syscon = clps_readl(SYSCON1);
 164         clps_writel(syscon & ~SYSCON1_LCDEN, SYSCON1);
 165         clps_writel(lcdcon, LCDCON);
 166         clps_writel(syscon | SYSCON1_LCDEN, SYSCON1);
 167         return 0;
 168 }
 169
 170 static int clps7111fb_blank(int blank, struct fb_info *info)
 171 {
 172         if (blank) {
 173                 if (machine_is_edb7211()) {
 174                         /* Turn off the LCD backlight. */
 175                         clps_writeb(clps_readb(PDDR) & ~EDB_PD3_LCDBL, PDDR);
 176
 177                         /* Power off the LCD DC-DC converter. */
 178                         clps_writeb(clps_readb(PDDR) & ~EDB_PD1_LCD_DC_DC_EN, PDDR);
 179
 180                         /* Delay for a little while (half a second). */
 181                         udelay(100);
 182
 183                         /* Power off the LCD panel. */
 184                         clps_writeb(clps_readb(PDDR) & ~EDB_PD2_LCDEN, PDDR);
 185
 186                         /* Power off the LCD controller. */
 187                         clps_writel(clps_readl(SYSCON1) & ~SYSCON1_LCDEN,
 188                                         SYSCON1);
 189                 }
 190         } else {
 191                 if (machine_is_edb7211()) {
 192                         /* Power up the LCD controller. */
 193                         clps_writel(clps_readl(SYSCON1) | SYSCON1_LCDEN,
 194                                         SYSCON1);
 195
 196                         /* Power up the LCD panel. */
 197                         clps_writeb(clps_readb(PDDR) | EDB_PD2_LCDEN, PDDR);
 198
 199                         /* Delay for a little while. */
 200                         udelay(100);
 201
 202                         /* Power up the LCD DC-DC converter. */
 203                         clps_writeb(clps_readb(PDDR) | EDB_PD1_LCD_DC_DC_EN,
 204                                         PDDR);
 205
 206                         /* Turn on the LCD backlight. */
 207                         clps_writeb(clps_readb(PDDR) | EDB_PD3_LCDBL, PDDR);
 208                 }
 209         }
 210         return 0;
 211 }
 212
 213 static struct fb_ops clps7111fb_ops = {
 214         .owner          = THIS_MODULE,
 215         .fb_check_var   = clps7111fb_check_var,
 216         .fb_set_par     = clps7111fb_set_par,
 217         .fb_setcolreg   = clps7111fb_setcolreg,
 218         .fb_blank       = clps7111fb_blank,
 219         .fb_fillrect    = cfb_fillrect,
 220         .fb_copyarea    = cfb_copyarea,
 221         .fb_imageblit   = cfb_imageblit,
 222 };
 223
 224 static int
 225 clps7111fb_proc_backlight_read(char *page, char **start, off_t off,
 226                 int count, int *eof, void *data)
 227 {
 228         /* We need at least two characters, one for the digit, and one for
 229          * the terminating NULL. */
 230         if (count < 2)
 231                 return -EINVAL;
 232
 233         if (machine_is_edb7211()) {
 234                 return sprintf(page, "%d\n",
 235                                 (clps_readb(PDDR) & EDB_PD3_LCDBL) ? 1 : 0);
 236         }
 237
 238         return 0;
 239 }
 240
 241 static int
 242 clps7111fb_proc_backlight_write(struct file *file, const char *buffer,
 243                 unsigned long count, void *data)
 244 {
 245         unsigned char char_value;
 246         int value;
 247
 248         if (count < 1) {
 249                 return -EINVAL;
 250         }
 251
 252         if (copy_from_user(&char_value, buffer, 1))
 253                 return -EFAULT;
 254
 255         value = char_value - '0';
 256
 257         if (machine_is_edb7211()) {
 258                 unsigned char port_d;
 259
 260                 port_d = clps_readb(PDDR);
 261
 262                 if (value) {
 263                         port_d |= EDB_PD3_LCDBL;
 264                 } else {
 265                         port_d &= ~EDB_PD3_LCDBL;
 266                 }
 267
 268                 clps_writeb(port_d, PDDR);
 269         }
 270
 271         return count;
 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 = kmalloc(sizeof(*cfb), GFP_KERNEL);
 370         if (!cfb)
 371                 goto out;
 372
 373         memset(cfb, 0, sizeof(*cfb));
 374         strcpy(cfb->fix.id, "clps711x");
 375
 376         cfb->fbops              = &clps7111fb_ops;
 377         cfb->flags              = FBINFO_DEFAULT;
 378
 379         clps711x_guess_lcd_params(cfb);
 380
 381         fb_alloc_cmap(&cfb->cmap, CMAP_MAX_SIZE, 0);
 382
 383         /* Register the /proc entries. */
 384         clps7111fb_backlight_proc_entry = create_proc_entry("backlight", 0444,
 385                 &proc_root);
 386         if (clps7111fb_backlight_proc_entry == NULL) {
 387                 printk("Couldn't create the /proc entry for the backlight.\n");
 388                 return -EINVAL;
 389         }
 390
 391         clps7111fb_backlight_proc_entry->read_proc =
 392                 &clps7111fb_proc_backlight_read;
 393         clps7111fb_backlight_proc_entry->write_proc =
 394                 &clps7111fb_proc_backlight_write;
 395
 396         /*
 397          * Power up the LCD
 398          */
 399         if (machine_is_p720t()) {
 400                 PLD_LCDEN = PLD_LCDEN_EN;
 401                 PLD_PWR |= (PLD_S4_ON|PLD_S3_ON|PLD_S2_ON|PLD_S1_ON);
 402         }
 403
 404         if (machine_is_edb7211()) {
 405                 /* Power up the LCD panel. */
 406                 clps_writeb(clps_readb(PDDR) | EDB_PD2_LCDEN, PDDR);
 407
 408                 /* Delay for a little while. */
 409                 udelay(100);
 410
 411                 /* Power up the LCD DC-DC converter. */
 412                 clps_writeb(clps_readb(PDDR) | EDB_PD1_LCD_DC_DC_EN, PDDR);
 413
 414                 /* Turn on the LCD backlight. */
 415                 clps_writeb(clps_readb(PDDR) | EDB_PD3_LCDBL, PDDR);
 416         }
 417
 418         err = register_framebuffer(cfb);
 419
 420 out:    return err;
 421 }
 422
 423 static void __exit clps711xfb_exit(void)
 424 {
 425         unregister_framebuffer(cfb);
 426         kfree(cfb);
 427
 428         /*
 429          * Power down the LCD
 430          */
 431         if (machine_is_p720t()) {
 432                 PLD_LCDEN = 0;
 433                 PLD_PWR &= ~(PLD_S4_ON|PLD_S3_ON|PLD_S2_ON|PLD_S1_ON);
 434         }
 435 }
 436
 437 module_init(clps711xfb_init);
 438 module_exit(clps711xfb_exit);
 439
 440 MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
 441 MODULE_DESCRIPTION("CLPS711x framebuffer driver");
 442 MODULE_LICENSE("GPL");