drivers/staging/olpc_dcon/olpc_dcon.c

   1 /*
   2  * Mainly by David Woodhouse, somewhat modified by Jordan Crouse
   3  *
   4  * Copyright © 2006-2007  Red Hat, Inc.
   5  * Copyright © 2006-2007  Advanced Micro Devices, Inc.
   6  * Copyright © 2009       VIA Technology, Inc.
   7  * Copyright (c) 2010  Andres Salomon <dilinger@queued.net>
   8  *
   9  * This program is free software.  You can redistribute it and/or
  10  * modify it under the terms of version 2 of the GNU General Public
  11  * License as published by the Free Software Foundation.
  12  */
  13
  14
  15 #include <linux/kernel.h>
  16 #include <linux/fb.h>
  17 #include <linux/console.h>
  18 #include <linux/i2c.h>
  19 #include <linux/platform_device.h>
  20 #include <linux/i2c-id.h>
  21 #include <linux/pci.h>
  22 #include <linux/vt_kern.h>
  23 #include <linux/pci_ids.h>
  24 #include <linux/interrupt.h>
  25 #include <linux/delay.h>
  26 #include <linux/backlight.h>
  27 #include <linux/device.h>
  28 #include <linux/notifier.h>
  29 #include <asm/uaccess.h>
  30 #include <linux/ctype.h>
  31 #include <linux/reboot.h>
  32 #include <linux/gpio.h>
  33 #include <asm/tsc.h>
  34 #include <asm/olpc.h>
  35
  36 #include "olpc_dcon.h"
  37
  38 /* Module definitions */
  39
  40 static int resumeline = 898;
  41 module_param(resumeline, int, 0444);
  42
  43 static int noinit;
  44 module_param(noinit, int, 0444);
  45
  46 /* Default off since it doesn't work on DCON ASIC in B-test OLPC board */
  47 static int useaa = 1;
  48 module_param(useaa, int, 0444);
  49
  50 struct dcon_platform_data {
  51         int (*init)(void);
  52         void (*bus_stabilize_wiggle)(void);
  53         void (*set_dconload)(int);
  54         int (*read_status)(void);
  55 };
  56
  57 static struct dcon_platform_data *pdata;
  58
  59 /* I2C structures */
  60
  61 static struct i2c_driver dcon_driver;
  62 static struct i2c_client *dcon_client;
  63
  64 /* Platform devices */
  65 static struct platform_device *dcon_device;
  66
  67 /* Backlight device */
  68 static struct backlight_device *dcon_bl_dev;
  69
  70 static struct fb_info *fbinfo;
  71
  72 /* set this to 1 while controlling fb blank state from this driver */
  73 static int ignore_fb_events = 0;
  74
  75 /* Current source, initialized at probe time */
  76 static int dcon_source;
  77
  78 /* Desired source */
  79 static int dcon_pending;
  80
  81 /* Current output type */
  82 static int dcon_output = DCON_OUTPUT_COLOR;
  83
  84 /* Current sleep status (not yet implemented) */
  85 static int dcon_sleep_val = DCON_ACTIVE;
  86
  87 /* Shadow register for the DCON_REG_MODE register */
  88 static unsigned short dcon_disp_mode;
  89
  90 /* Variables used during switches */
  91 static int dcon_switched;
  92 static struct timespec dcon_irq_time;
  93 static struct timespec dcon_load_time;
  94
  95 static DECLARE_WAIT_QUEUE_HEAD(dcon_wait_queue);
  96
  97 static unsigned short normal_i2c[] = { 0x0d, I2C_CLIENT_END };
  98
  99 #define dcon_write(reg,val) i2c_smbus_write_word_data(dcon_client,reg,val)
 100 #define dcon_read(reg) i2c_smbus_read_word_data(dcon_client,reg)
 101
 102 /* The current backlight value - this saves us some smbus traffic */
 103 static int bl_val = -1;
 104
 105 /* ===== API functions - these are called by a variety of users ==== */
 106
 107 static int dcon_hw_init(struct i2c_client *client, int is_init)
 108 {
 109         uint16_t ver;
 110         int rc = 0;
 111
 112         ver = i2c_smbus_read_word_data(client, DCON_REG_ID);
 113         if ((ver >> 8) != 0xDC) {
 114                 printk(KERN_ERR "olpc-dcon:  DCON ID not 0xDCxx: 0x%04x "
 115                                 "instead.\n", ver);
 116                 rc = -ENXIO;
 117                 goto err;
 118         }
 119
 120         if (is_init) {
 121                 printk(KERN_INFO "olpc-dcon:  Discovered DCON version %x\n",
 122                                 ver & 0xFF);
 123                 if ((rc = pdata->init()) != 0) {
 124                         printk(KERN_ERR "olpc-dcon:  Unable to init.\n");
 125                         goto err;
 126                 }
 127         }
 128
 129         if (ver < 0xdc02 && !noinit) {
 130                 /* Initialize the DCON registers */
 131
 132                 /* Start with work-arounds for DCON ASIC */
 133                 i2c_smbus_write_word_data(client, 0x4b, 0x00cc);
 134                 i2c_smbus_write_word_data(client, 0x4b, 0x00cc);
 135                 i2c_smbus_write_word_data(client, 0x4b, 0x00cc);
 136                 i2c_smbus_write_word_data(client, 0x0b, 0x007a);
 137                 i2c_smbus_write_word_data(client, 0x36, 0x025c);
 138                 i2c_smbus_write_word_data(client, 0x37, 0x025e);
 139
 140                 /* Initialise SDRAM */
 141
 142                 i2c_smbus_write_word_data(client, 0x3b, 0x002b);
 143                 i2c_smbus_write_word_data(client, 0x41, 0x0101);
 144                 i2c_smbus_write_word_data(client, 0x42, 0x0101);
 145         }
 146         else if (!noinit) {
 147                 /* SDRAM setup/hold time */
 148                 i2c_smbus_write_word_data(client, 0x3a, 0xc040);
 149                 i2c_smbus_write_word_data(client, 0x41, 0x0000);
 150                 i2c_smbus_write_word_data(client, 0x41, 0x0101);
 151                 i2c_smbus_write_word_data(client, 0x42, 0x0101);
 152         }
 153
 154         /* Colour swizzle, AA, no passthrough, backlight */
 155         if (is_init) {
 156                 dcon_disp_mode = MODE_PASSTHRU | MODE_BL_ENABLE | MODE_CSWIZZLE;
 157                 if (useaa)
 158                         dcon_disp_mode |= MODE_COL_AA;
 159         }
 160         i2c_smbus_write_word_data(client, DCON_REG_MODE, dcon_disp_mode);
 161
 162
 163         /* Set the scanline to interrupt on during resume */
 164         i2c_smbus_write_word_data(client, DCON_REG_SCAN_INT, resumeline);
 165
 166 err:
 167         return rc;
 168 }
 169
 170 /*
 171  * The smbus doesn't always come back due to what is believed to be
 172  * hardware (power rail) bugs.  For older models where this is known to
 173  * occur, our solution is to attempt to wait for the bus to stabilize;
 174  * if it doesn't happen, cut power to the dcon, repower it, and wait
 175  * for the bus to stabilize.  Rinse, repeat until we have a working
 176  * smbus.  For newer models, we simply BUG(); we want to know if this
 177  * still happens despite the power fixes that have been made!
 178  */
 179 static int dcon_bus_stabilize(struct i2c_client *client, int is_powered_down)
 180 {
 181         unsigned long timeout;
 182         int x;
 183
 184 power_up:
 185         if (is_powered_down) {
 186                 x = 1;
 187                 if ((x = olpc_ec_cmd(0x26, (unsigned char *) &x, 1, NULL, 0))) {
 188                         printk(KERN_WARNING "olpc-dcon:  unable to force dcon "
 189                                         "to power up: %d!\n", x);
 190                         return x;
 191                 }
 192                 msleep(10); /* we'll be conservative */
 193         }
 194
 195         pdata->bus_stabilize_wiggle();
 196
 197         for (x = -1, timeout = 50; timeout && x < 0; timeout--) {
 198                 msleep(1);
 199                 x = dcon_read(DCON_REG_ID);
 200         }
 201         if (x < 0) {
 202                 printk(KERN_ERR "olpc-dcon:  unable to stabilize dcon's "
 203                                 "smbus, reasserting power and praying.\n");
 204                 BUG_ON(olpc_board_at_least(olpc_board(0xc2)));
 205                 x = 0;
 206                 olpc_ec_cmd(0x26, (unsigned char *) &x, 1, NULL, 0);
 207                 msleep(100);
 208                 is_powered_down = 1;
 209                 goto power_up;  /* argh, stupid hardware.. */
 210         }
 211
 212         if (is_powered_down)
 213                 return dcon_hw_init(client, 0);
 214         return 0;
 215 }
 216
 217
 218 /* Backlight notes - turning off the backlight enable bit in the DCON
 219  * doesn't save us any power over just pushing the BL to zero, so we
 220  * don't use that bit in this code.
 221  */
 222
 223 static int dcon_get_backlight(void)
 224 {
 225         if (dcon_client == NULL)
 226                 return 0;
 227
 228         if (bl_val == -1)
 229                 bl_val = dcon_read(DCON_REG_BRIGHT) & 0x0F;
 230
 231         return bl_val;
 232 }
 233
 234
 235 static void dcon_set_backlight_hw(int level)
 236 {
 237         bl_val = level & 0x0F;
 238         dcon_write(DCON_REG_BRIGHT, bl_val);
 239
 240         /* Purposely turn off the backlight when we go to level 0 */
 241         if (bl_val == 0) {
 242                 dcon_disp_mode &= ~MODE_BL_ENABLE;
 243                 dcon_write(DCON_REG_MODE, dcon_disp_mode);
 244         } else if (!(dcon_disp_mode & MODE_BL_ENABLE)) {
 245                 dcon_disp_mode |= MODE_BL_ENABLE;
 246                 dcon_write(DCON_REG_MODE, dcon_disp_mode);
 247         }
 248 }
 249
 250 static void dcon_set_backlight(int level)
 251 {
 252         if (dcon_client == NULL)
 253                 return;
 254
 255         if (bl_val == (level & 0x0F))
 256                 return;
 257
 258         dcon_set_backlight_hw(level);
 259 }
 260
 261 /* Set the output type to either color or mono */
 262
 263 static int dcon_set_output(int arg)
 264 {
 265         if (dcon_output == arg)
 266                 return 0;
 267
 268         dcon_output = arg;
 269
 270         if (arg == DCON_OUTPUT_MONO) {
 271                 dcon_disp_mode &= ~(MODE_CSWIZZLE | MODE_COL_AA);
 272                 dcon_disp_mode |= MODE_MONO_LUMA;
 273         }
 274         else {
 275                 dcon_disp_mode &= ~(MODE_MONO_LUMA);
 276                 dcon_disp_mode |= MODE_CSWIZZLE;
 277                 if (useaa)
 278                         dcon_disp_mode |= MODE_COL_AA;
 279         }
 280
 281         dcon_write(DCON_REG_MODE, dcon_disp_mode);
 282         return 0;
 283 }
 284
 285 /* For now, this will be really stupid - we need to address how
 286  * DCONLOAD works in a sleep and account for it accordingly
 287  */
 288
 289 static void dcon_sleep(int state)
 290 {
 291         int x;
 292
 293         /* Turn off the backlight and put the DCON to sleep */
 294
 295         if (state == dcon_sleep_val)
 296                 return;
 297
 298         if (!olpc_board_at_least(olpc_board(0xc2)))
 299                 return;
 300
 301         if (state == DCON_SLEEP) {
 302                 x = 0;
 303                 if ((x = olpc_ec_cmd(0x26, (unsigned char *) &x, 1, NULL, 0)))
 304                         printk(KERN_WARNING "olpc-dcon:  unable to force dcon "
 305                                         "to power down: %d!\n", x);
 306                 else
 307                         dcon_sleep_val = state;
 308         }
 309         else {
 310                 /* Only re-enable the backlight if the backlight value is set */
 311                 if (bl_val != 0)
 312                         dcon_disp_mode |= MODE_BL_ENABLE;
 313
 314                 if ((x=dcon_bus_stabilize(dcon_client, 1)))
 315                         printk(KERN_WARNING "olpc-dcon:  unable to reinit dcon"
 316                                         " hardware: %d!\n", x);
 317                 else
 318                         dcon_sleep_val = state;
 319
 320                 /* Restore backlight */
 321                 dcon_set_backlight_hw(bl_val);
 322         }
 323
 324         /* We should turn off some stuff in the framebuffer - but what? */
 325 }
 326
 327 /* the DCON seems to get confused if we change DCONLOAD too
 328  * frequently -- i.e., approximately faster than frame time.
 329  * normally we don't change it this fast, so in general we won't
 330  * delay here.
 331  */
 332 void dcon_load_holdoff(void)
 333 {
 334         struct timespec delta_t, now;
 335         while(1) {
 336                 getnstimeofday(&now);
 337                 delta_t = timespec_sub(now, dcon_load_time);
 338                 if (delta_t.tv_sec != 0 ||
 339                         delta_t.tv_nsec > NSEC_PER_MSEC * 20) {
 340                         break;
 341                 }
 342                 mdelay(4);
 343         }
 344 }
 345 /* Set the source of the display (CPU or DCON) */
 346
 347 static void dcon_source_switch(struct work_struct *work)
 348 {
 349         DECLARE_WAITQUEUE(wait, current);
 350         int source = dcon_pending;
 351
 352         if (dcon_source == source)
 353                 return;
 354
 355         dcon_load_holdoff();
 356
 357         dcon_switched = 0;
 358
 359         switch (source) {
 360         case DCON_SOURCE_CPU:
 361                 printk("dcon_source_switch to CPU\n");
 362                 /* Enable the scanline interrupt bit */
 363                 if (dcon_write(DCON_REG_MODE, dcon_disp_mode | MODE_SCAN_INT))
 364                         printk(KERN_ERR "olpc-dcon:  couldn't enable scanline interrupt!\n");
 365                 else {
 366                         /* Wait up to one second for the scanline interrupt */
 367                         wait_event_timeout(dcon_wait_queue, dcon_switched == 1, HZ);
 368                 }
 369
 370                 if (!dcon_switched)
 371                         printk(KERN_ERR "olpc-dcon:  Timeout entering CPU mode; expect a screen glitch.\n");
 372
 373                 /* Turn off the scanline interrupt */
 374                 if (dcon_write(DCON_REG_MODE, dcon_disp_mode))
 375                         printk(KERN_ERR "olpc-dcon:  couldn't disable scanline interrupt!\n");
 376
 377                 /*
 378                  * Ideally we'd like to disable interrupts here so that the
 379                  * fb unblanking and DCON turn on happen at a known time value;
 380                  * however, we can't do that right now with fb_blank
 381                  * messing with semaphores.
 382                  *
 383                  * For now, we just hope..
 384                  */
 385                 acquire_console_sem();
 386                 ignore_fb_events = 1;
 387                 if (fb_blank(fbinfo, FB_BLANK_UNBLANK)) {
 388                         ignore_fb_events = 0;
 389                         release_console_sem();
 390                         printk(KERN_ERR "olpc-dcon:  Failed to enter CPU mode\n");
 391                         dcon_pending = DCON_SOURCE_DCON;
 392                         return;
 393                 }
 394                 ignore_fb_events = 0;
 395                 release_console_sem();
 396
 397                 /* And turn off the DCON */
 398                 pdata->set_dconload(1);
 399                 getnstimeofday(&dcon_load_time);
 400
 401                 printk(KERN_INFO "olpc-dcon: The CPU has control\n");
 402                 break;
 403         case DCON_SOURCE_DCON:
 404         {
 405                 int t;
 406                 struct timespec delta_t;
 407
 408                 printk("dcon_source_switch to DCON\n");
 409
 410                 add_wait_queue(&dcon_wait_queue, &wait);
 411                 set_current_state(TASK_UNINTERRUPTIBLE);
 412
 413                 /* Clear DCONLOAD - this implies that the DCON is in control */
 414                 pdata->set_dconload(0);
 415                 getnstimeofday(&dcon_load_time);
 416
 417                 t = schedule_timeout(HZ/2);
 418                 remove_wait_queue(&dcon_wait_queue, &wait);
 419                 set_current_state(TASK_RUNNING);
 420
 421                 if (!dcon_switched) {
 422                         printk(KERN_ERR "olpc-dcon: Timeout entering DCON mode; expect a screen glitch.\n");
 423                 } else {
 424                         /* sometimes the DCON doesn't follow its own rules,
 425                          * and doesn't wait for two vsync pulses before
 426                          * ack'ing the frame load with an IRQ.  the result
 427                          * is that the display shows the *previously*
 428                          * loaded frame.  we can detect this by looking at
 429                          * the time between asserting DCONLOAD and the IRQ --
 430                          * if it's less than 20msec, then the DCON couldn't
 431                          * have seen two VSYNC pulses.  in that case we
 432                          * deassert and reassert, and hope for the best.
 433                          * see http://dev.laptop.org/ticket/9664
 434                          */
 435                         delta_t = timespec_sub(dcon_irq_time, dcon_load_time);
 436                         if (dcon_switched && delta_t.tv_sec == 0 &&
 437                                         delta_t.tv_nsec < NSEC_PER_MSEC * 20) {
 438                                 printk(KERN_ERR "olpc-dcon: missed loading, retrying\n");
 439                                 pdata->set_dconload(1);
 440                                 mdelay(41);
 441                                 pdata->set_dconload(0);
 442                                 getnstimeofday(&dcon_load_time);
 443                                 mdelay(41);
 444                         }
 445                 }
 446
 447                 acquire_console_sem();
 448                 ignore_fb_events = 1;
 449                 if (fb_blank(fbinfo, FB_BLANK_POWERDOWN))
 450                         printk(KERN_ERR "olpc-dcon:  couldn't blank fb!\n");
 451                 ignore_fb_events = 0;
 452                 release_console_sem();
 453
 454                 printk(KERN_INFO "olpc-dcon: The DCON has control\n");
 455                 break;
 456         }
 457         default:
 458                 BUG();
 459         }
 460
 461         dcon_source = source;
 462 }
 463
 464 static DECLARE_WORK(dcon_work, dcon_source_switch);
 465
 466 static void dcon_set_source(int arg)
 467 {
 468         if (dcon_pending == arg)
 469                 return;
 470
 471         dcon_pending = arg;
 472
 473         if ((dcon_source != arg) && !work_pending(&dcon_work))
 474                 schedule_work(&dcon_work);
 475 }
 476
 477 static void dcon_set_source_sync(int arg)
 478 {
 479         dcon_set_source(arg);
 480         flush_scheduled_work();
 481 }
 482
 483 static int dconbl_set(struct backlight_device *dev) {
 484
 485         int level = dev->props.brightness;
 486
 487         if (dev->props.power != FB_BLANK_UNBLANK)
 488                 level = 0;
 489
 490         dcon_set_backlight(level);
 491         return 0;
 492 }
 493
 494 static int dconbl_get(struct backlight_device *dev) {
 495         return dcon_get_backlight();
 496 }
 497
 498 static ssize_t dcon_mode_show(struct device *dev,
 499         struct device_attribute *attr, char *buf)
 500 {
 501         return sprintf(buf, "%4.4X\n", dcon_disp_mode);
 502 }
 503
 504 static ssize_t dcon_sleep_show(struct device *dev,
 505         struct device_attribute *attr, char *buf)
 506 {
 507
 508         return sprintf(buf, "%d\n", dcon_sleep_val);
 509 }
 510
 511 static ssize_t dcon_freeze_show(struct device *dev,
 512         struct device_attribute *attr, char *buf)
 513 {
 514         return sprintf(buf, "%d\n", dcon_source == DCON_SOURCE_DCON ? 1 : 0);
 515 }
 516
 517 static ssize_t dcon_output_show(struct device *dev,
 518         struct device_attribute *attr, char *buf)
 519 {
 520         return sprintf(buf, "%d\n", dcon_output);
 521 }
 522
 523 static ssize_t dcon_resumeline_show(struct device *dev,
 524         struct device_attribute *attr, char *buf)
 525 {
 526         return sprintf(buf, "%d\n", resumeline);
 527 }
 528
 529 static int _strtoul(const char *buf, int len, unsigned int *val)
 530 {
 531
 532         char *endp;
 533         unsigned int output = simple_strtoul(buf, &endp, 0);
 534         int size = endp - buf;
 535
 536         if (*endp && isspace(*endp))
 537                 size++;
 538
 539         if (size != len)
 540                 return -EINVAL;
 541
 542         *val = output;
 543         return 0;
 544 }
 545
 546 static ssize_t dcon_output_store(struct device *dev,
 547         struct device_attribute *attr, const char *buf, size_t count)
 548 {
 549         int output;
 550         int rc = -EINVAL;
 551
 552         if (_strtoul(buf, count, &output))
 553                 return -EINVAL;
 554
 555         if (output == DCON_OUTPUT_COLOR || output == DCON_OUTPUT_MONO) {
 556                 dcon_set_output(output);
 557                 rc = count;
 558         }
 559
 560         return rc;
 561 }
 562
 563 static ssize_t dcon_freeze_store(struct device *dev,
 564         struct device_attribute *attr, const char *buf, size_t count)
 565 {
 566         int output;
 567
 568         if (_strtoul(buf, count, &output))
 569                 return -EINVAL;
 570
 571         printk("dcon_freeze_store: %d\n", output);
 572
 573         switch (output) {
 574         case 0:
 575                 dcon_set_source(DCON_SOURCE_CPU);
 576                 break;
 577         case 1:
 578                 dcon_set_source_sync(DCON_SOURCE_DCON);
 579                 break;
 580         case 2:  // normally unused
 581                 dcon_set_source(DCON_SOURCE_DCON);
 582                 break;
 583         default:
 584                 return -EINVAL;
 585         }
 586
 587         return count;
 588 }
 589
 590 static ssize_t dcon_resumeline_store(struct device *dev,
 591         struct device_attribute *attr, const char *buf, size_t count)
 592 {
 593         int rl;
 594         int rc = -EINVAL;
 595
 596         if (_strtoul(buf, count, &rl))
 597                 return rc;
 598
 599         resumeline = rl;
 600         dcon_write(DCON_REG_SCAN_INT, resumeline);
 601         rc = count;
 602
 603         return rc;
 604 }
 605
 606 static ssize_t dcon_sleep_store(struct device *dev,
 607         struct device_attribute *attr, const char *buf, size_t count)
 608 {
 609         int output;
 610
 611         if (_strtoul(buf, count, &output))
 612                 return -EINVAL;
 613
 614         dcon_sleep(output ? DCON_SLEEP : DCON_ACTIVE);
 615         return count;
 616 }
 617
 618 static struct device_attribute dcon_device_files[] = {
 619         __ATTR(mode, 0444, dcon_mode_show, NULL),
 620         __ATTR(sleep, 0644, dcon_sleep_show, dcon_sleep_store),
 621         __ATTR(freeze, 0644, dcon_freeze_show, dcon_freeze_store),
 622         __ATTR(output, 0644, dcon_output_show, dcon_output_store),
 623         __ATTR(resumeline, 0644, dcon_resumeline_show, dcon_resumeline_store),
 624 };
 625
 626 static struct backlight_ops dcon_bl_ops = {
 627         .get_brightness = dconbl_get,
 628         .update_status = dconbl_set
 629 };
 630
 631
 632 static int dcon_reboot_notify(struct notifier_block *nb, unsigned long foo, void *bar)
 633 {
 634         if (dcon_client == NULL)
 635                 return 0;
 636
 637         /* Turn off the DCON. Entirely. */
 638         dcon_write(DCON_REG_MODE, 0x39);
 639         dcon_write(DCON_REG_MODE, 0x32);
 640         return 0;
 641 }
 642
 643 static int dcon_conswitch_notify(struct notifier_block *nb,
 644                                  unsigned long mode, void *dummy)
 645 {
 646         if (mode == CONSOLE_EVENT_SWITCH_TEXT)
 647                 dcon_sleep(DCON_ACTIVE);
 648
 649         return 0;
 650 }
 651
 652 static struct notifier_block dcon_nb = {
 653         .notifier_call = dcon_reboot_notify,
 654         .priority = -1,
 655 };
 656
 657 static struct notifier_block dcon_console_nb = {
 658         .notifier_call = dcon_conswitch_notify,
 659         .priority = -1,
 660 };
 661
 662 static int unfreeze_on_panic(struct notifier_block *nb, unsigned long e, void *p)
 663 {
 664         pdata->set_dconload(1);
 665         return NOTIFY_DONE;
 666 }
 667
 668 static struct notifier_block dcon_panic_nb = {
 669         .notifier_call = unfreeze_on_panic,
 670 };
 671
 672 /* when framebuffer sleeps due to external source (e.g. user idle), power down
 673  * the DCON. also power up when the framebuffer comes back to life. */
 674 static int fb_notifier_callback(struct notifier_block *self, unsigned long event, void *data)
 675 {
 676         struct fb_event *evdata = data;
 677         int *blank = (int *) evdata->data;
 678         if (event != FB_EVENT_BLANK || ignore_fb_events)
 679                 return 0;
 680         dcon_sleep((*blank) ? DCON_SLEEP : DCON_ACTIVE);
 681         return 0;
 682 }
 683
 684 static struct notifier_block fb_nb = {
 685         .notifier_call = fb_notifier_callback,
 686 };
 687
 688 static int dcon_detect(struct i2c_client *client, struct i2c_board_info *info)
 689 {
 690         strlcpy(info->type, "olpc_dcon", I2C_NAME_SIZE);
 691
 692         return 0;
 693 }
 694
 695 static int dcon_probe(struct i2c_client *client, const struct i2c_device_id *id)
 696 {
 697         int rc, i;
 698
 699         if (num_registered_fb >= 1)
 700                 fbinfo = registered_fb[0];
 701
 702         rc = dcon_hw_init(client, 1);
 703         if (rc)
 704                 goto einit;
 705
 706         /* Add the DCON device */
 707
 708         dcon_device = platform_device_alloc("dcon", -1);
 709
 710         if (dcon_device == NULL) {
 711                 printk("dcon:  Unable to create the DCON device\n");
 712                 rc = -ENOMEM;
 713                 goto eirq;
 714         }
 715         /* Place holder...*/
 716         i2c_set_clientdata(client, dcon_device);
 717
 718         if ((rc = platform_device_add(dcon_device))) {
 719                 printk("dcon:  Unable to add the DCON device\n");
 720                 goto edev;
 721         }
 722
 723         for(i = 0; i < ARRAY_SIZE(dcon_device_files); i++)
 724                 device_create_file(&dcon_device->dev, &dcon_device_files[i]);
 725
 726         /* Add the backlight device for the DCON */
 727
 728         dcon_client = client;
 729
 730         dcon_bl_dev = backlight_device_register("dcon-bl", &dcon_device->dev,
 731                 NULL, &dcon_bl_ops, NULL);
 732
 733         if (IS_ERR(dcon_bl_dev)) {
 734                 printk("Could not register the backlight device for the DCON (%ld)\n", PTR_ERR(dcon_bl_dev));
 735                 dcon_bl_dev = NULL;
 736         }
 737         else {
 738                 dcon_bl_dev->props.max_brightness = 15;
 739                 dcon_bl_dev->props.power = FB_BLANK_UNBLANK;
 740                 dcon_bl_dev->props.brightness = dcon_get_backlight();
 741
 742                 backlight_update_status(dcon_bl_dev);
 743         }
 744
 745         register_reboot_notifier(&dcon_nb);
 746         console_event_register(&dcon_console_nb);
 747         atomic_notifier_chain_register(&panic_notifier_list, &dcon_panic_nb);
 748         fb_register_client(&fb_nb);
 749
 750         return 0;
 751
 752  edev:
 753         platform_device_unregister(dcon_device);
 754         dcon_device = NULL;
 755         i2c_set_clientdata(client, NULL);
 756  eirq:
 757         free_irq(DCON_IRQ, &dcon_driver);
 758  einit:
 759         return rc;
 760 }
 761
 762 static int dcon_remove(struct i2c_client *client)
 763 {
 764         dcon_client = NULL;
 765
 766         fb_unregister_client(&fb_nb);
 767         unregister_reboot_notifier(&dcon_nb);
 768         console_event_unregister(&dcon_console_nb);
 769         atomic_notifier_chain_unregister(&panic_notifier_list, &dcon_panic_nb);
 770
 771         free_irq(DCON_IRQ, &dcon_driver);
 772
 773         if (dcon_bl_dev != NULL)
 774                 backlight_device_unregister(dcon_bl_dev);
 775
 776         if (dcon_device != NULL)
 777                 platform_device_unregister(dcon_device);
 778         cancel_work_sync(&dcon_work);
 779
 780         i2c_set_clientdata(client, NULL);
 781
 782         return 0;
 783 }
 784
 785 #ifdef CONFIG_PM
 786 static int dcon_suspend(struct i2c_client *client, pm_message_t state)
 787 {
 788         if (dcon_sleep_val == DCON_ACTIVE) {
 789                 /* Set up the DCON to have the source */
 790                 dcon_set_source_sync(DCON_SOURCE_DCON);
 791         }
 792
 793         return 0;
 794 }
 795
 796 static int dcon_resume(struct i2c_client *client)
 797 {
 798         if (dcon_sleep_val == DCON_ACTIVE) {
 799                 dcon_bus_stabilize(client, 0);
 800                 dcon_set_source(DCON_SOURCE_CPU);
 801         }
 802
 803         return 0;
 804 }
 805
 806 #endif
 807
 808
 809 static irqreturn_t dcon_interrupt(int irq, void *id)
 810 {
 811         int status = pdata->read_status();
 812
 813         if (status == -1)
 814                 return IRQ_NONE;
 815
 816         switch (status & 3) {
 817         case 3:
 818                 printk(KERN_DEBUG "olpc-dcon: DCONLOAD_MISSED interrupt\n");
 819                 break;
 820
 821         case 2: /* switch to DCON mode */
 822         case 1: /* switch to CPU mode */
 823                 dcon_switched = 1;
 824                 getnstimeofday(&dcon_irq_time);
 825                 wake_up(&dcon_wait_queue);
 826                 break;
 827
 828         case 0:
 829                 /* workaround resume case:  the DCON (on 1.5) doesn't
 830                  * ever assert status 0x01 when switching to CPU mode
 831                  * during resume.  this is because DCONLOAD is de-asserted
 832                  * _immediately_ upon exiting S3, so the actual release
 833                  * of the DCON happened long before this point.
 834                  * see http://dev.laptop.org/ticket/9869
 835                  */
 836                 if (dcon_source != dcon_pending && !dcon_switched) {
 837                         dcon_switched = 1;
 838                         getnstimeofday(&dcon_irq_time);
 839                         wake_up(&dcon_wait_queue);
 840                         printk(KERN_DEBUG "olpc-dcon: switching w/ status 0/0\n");
 841                 } else {
 842                         printk(KERN_DEBUG "olpc-dcon: scanline interrupt w/CPU\n");
 843                 }
 844         }
 845
 846         return IRQ_HANDLED;
 847 }
 848
 849 static struct i2c_device_id dcon_idtable[] = {
 850         { "olpc_dcon",  0 },
 851         { }
 852 };
 853
 854 MODULE_DEVICE_TABLE(i2c, dcon_idtable);
 855
 856 static struct i2c_driver dcon_driver = {
 857         .driver = {
 858                 .name   = "olpc_dcon",
 859         },
 860         .class = I2C_CLASS_DDC | I2C_CLASS_HWMON,
 861         .id_table = dcon_idtable,
 862         .probe = dcon_probe,
 863         .remove = __devexit_p(dcon_remove),
 864         .detect = dcon_detect,
 865         .address_list = normal_i2c,
 866 #ifdef CONFIG_PM
 867         .suspend = dcon_suspend,
 868         .resume = dcon_resume,
 869 #endif
 870 };
 871
 872 #include "olpc_dcon_xo_1.c"
 873
 874 static int __init olpc_dcon_init(void)
 875 {
 876         pdata = &dcon_pdata_xo_1;
 877
 878         i2c_add_driver(&dcon_driver);
 879         return 0;
 880 }
 881
 882 static void __exit olpc_dcon_exit(void)
 883 {
 884         i2c_del_driver(&dcon_driver);
 885 }
 886
 887 module_init(olpc_dcon_init);
 888 module_exit(olpc_dcon_exit);
 889
 890 MODULE_LICENSE("GPL");