arch/powerpc/platforms/powermac/low_i2c.c

   1 /*
   2  * arch/powerpc/platforms/powermac/low_i2c.c
   3  *
   4  *  Copyright (C) 2003-2005 Ben. Herrenschmidt (benh@kernel.crashing.org)
   5  *
   6  *  This program is free software; you can redistribute it and/or
   7  *  modify it under the terms of the GNU General Public License
   8  *  as published by the Free Software Foundation; either version
   9  *  2 of the License, or (at your option) any later version.
  10  *
  11  * The linux i2c layer isn't completely suitable for our needs for various
  12  * reasons ranging from too late initialisation to semantics not perfectly
  13  * matching some requirements of the apple platform functions etc...
  14  *
  15  * This file thus provides a simple low level unified i2c interface for
  16  * powermac that covers the various types of i2c busses used in Apple machines.
  17  * For now, keywest, PMU and SMU, though we could add Cuda, or other bit
  18  * banging busses found on older chipstes in earlier machines if we ever need
  19  * one of them.
  20  *
  21  * The drivers in this file are synchronous/blocking. In addition, the
  22  * keywest one is fairly slow due to the use of msleep instead of interrupts
  23  * as the interrupt is currently used by i2c-keywest. In the long run, we
  24  * might want to get rid of those high-level interfaces to linux i2c layer
  25  * either completely (converting all drivers) or replacing them all with a
  26  * single stub driver on top of this one. Once done, the interrupt will be
  27  * available for our use.
  28  */
  29
  30 #undef DEBUG
  31 #undef DEBUG_LOW
  32
  33 #include <linux/types.h>
  34 #include <linux/sched.h>
  35 #include <linux/init.h>
  36 #include <linux/module.h>
  37 #include <linux/adb.h>
  38 #include <linux/pmu.h>
  39 #include <linux/delay.h>
  40 #include <linux/completion.h>
  41 #include <linux/platform_device.h>
  42 #include <linux/interrupt.h>
  43 #include <linux/completion.h>
  44 #include <linux/timer.h>
  45 #include <asm/keylargo.h>
  46 #include <asm/uninorth.h>
  47 #include <asm/io.h>
  48 #include <asm/prom.h>
  49 #include <asm/machdep.h>
  50 #include <asm/smu.h>
  51 #include <asm/pmac_pfunc.h>
  52 #include <asm/pmac_low_i2c.h>
  53
  54 #ifdef DEBUG
  55 #define DBG(x...) do {\
  56                 printk(KERN_DEBUG "low_i2c:" x);        \
  57         } while(0)
  58 #else
  59 #define DBG(x...)
  60 #endif
  61
  62 #ifdef DEBUG_LOW
  63 #define DBG_LOW(x...) do {\
  64                 printk(KERN_DEBUG "low_i2c:" x);        \
  65         } while(0)
  66 #else
  67 #define DBG_LOW(x...)
  68 #endif
  69
  70
  71 static int pmac_i2c_force_poll = 1;
  72
  73 /*
  74  * A bus structure. Each bus in the system has such a structure associated.
  75  */
  76 struct pmac_i2c_bus
  77 {
  78         struct list_head        link;
  79         struct device_node      *controller;
  80         struct device_node      *busnode;
  81         int                     type;
  82         int                     flags;
  83         struct i2c_adapter      *adapter;
  84         void                    *hostdata;
  85         int                     channel;        /* some hosts have multiple */
  86         int                     mode;           /* current mode */
  87         struct semaphore        sem;
  88         int                     opened;
  89         int                     polled;         /* open mode */
  90         struct platform_device  *platform_dev;
  91
  92         /* ops */
  93         int (*open)(struct pmac_i2c_bus *bus);
  94         void (*close)(struct pmac_i2c_bus *bus);
  95         int (*xfer)(struct pmac_i2c_bus *bus, u8 addrdir, int subsize,
  96                     u32 subaddr, u8 *data, int len);
  97 };
  98
  99 static LIST_HEAD(pmac_i2c_busses);
 100
 101 /*
 102  * Keywest implementation
 103  */
 104
 105 struct pmac_i2c_host_kw
 106 {
 107         struct semaphore        mutex;          /* Access mutex for use by
 108                                                  * i2c-keywest */
 109         void __iomem            *base;          /* register base address */
 110         int                     bsteps;         /* register stepping */
 111         int                     speed;          /* speed */
 112         int                     irq;
 113         u8                      *data;
 114         unsigned                len;
 115         int                     state;
 116         int                     rw;
 117         int                     polled;
 118         int                     result;
 119         struct completion       complete;
 120         spinlock_t              lock;
 121         struct timer_list       timeout_timer;
 122 };
 123
 124 /* Register indices */
 125 typedef enum {
 126         reg_mode = 0,
 127         reg_control,
 128         reg_status,
 129         reg_isr,
 130         reg_ier,
 131         reg_addr,
 132         reg_subaddr,
 133         reg_data
 134 } reg_t;
 135
 136 /* The Tumbler audio equalizer can be really slow sometimes */
 137 #define KW_POLL_TIMEOUT         (2*HZ)
 138
 139 /* Mode register */
 140 #define KW_I2C_MODE_100KHZ      0x00
 141 #define KW_I2C_MODE_50KHZ       0x01
 142 #define KW_I2C_MODE_25KHZ       0x02
 143 #define KW_I2C_MODE_DUMB        0x00
 144 #define KW_I2C_MODE_STANDARD    0x04
 145 #define KW_I2C_MODE_STANDARDSUB 0x08
 146 #define KW_I2C_MODE_COMBINED    0x0C
 147 #define KW_I2C_MODE_MODE_MASK   0x0C
 148 #define KW_I2C_MODE_CHAN_MASK   0xF0
 149
 150 /* Control register */
 151 #define KW_I2C_CTL_AAK          0x01
 152 #define KW_I2C_CTL_XADDR        0x02
 153 #define KW_I2C_CTL_STOP         0x04
 154 #define KW_I2C_CTL_START        0x08
 155
 156 /* Status register */
 157 #define KW_I2C_STAT_BUSY        0x01
 158 #define KW_I2C_STAT_LAST_AAK    0x02
 159 #define KW_I2C_STAT_LAST_RW     0x04
 160 #define KW_I2C_STAT_SDA         0x08
 161 #define KW_I2C_STAT_SCL         0x10
 162
 163 /* IER & ISR registers */
 164 #define KW_I2C_IRQ_DATA         0x01
 165 #define KW_I2C_IRQ_ADDR         0x02
 166 #define KW_I2C_IRQ_STOP         0x04
 167 #define KW_I2C_IRQ_START        0x08
 168 #define KW_I2C_IRQ_MASK         0x0F
 169
 170 /* State machine states */
 171 enum {
 172         state_idle,
 173         state_addr,
 174         state_read,
 175         state_write,
 176         state_stop,
 177         state_dead
 178 };
 179
 180 #define WRONG_STATE(name) do {\
 181                 printk(KERN_DEBUG "KW: wrong state. Got %s, state: %s " \
 182                        "(isr: %02x)\n", \
 183                        name, __kw_state_names[host->state], isr); \
 184         } while(0)
 185
 186 static const char *__kw_state_names[] = {
 187         "state_idle",
 188         "state_addr",
 189         "state_read",
 190         "state_write",
 191         "state_stop",
 192         "state_dead"
 193 };
 194
 195 static inline u8 __kw_read_reg(struct pmac_i2c_host_kw *host, reg_t reg)
 196 {
 197         return readb(host->base + (((unsigned int)reg) << host->bsteps));
 198 }
 199
 200 static inline void __kw_write_reg(struct pmac_i2c_host_kw *host,
 201                                   reg_t reg, u8 val)
 202 {
 203         writeb(val, host->base + (((unsigned)reg) << host->bsteps));
 204         (void)__kw_read_reg(host, reg_subaddr);
 205 }
 206
 207 #define kw_write_reg(reg, val)  __kw_write_reg(host, reg, val)
 208 #define kw_read_reg(reg)        __kw_read_reg(host, reg)
 209
 210 static u8 kw_i2c_wait_interrupt(struct pmac_i2c_host_kw *host)
 211 {
 212         int i, j;
 213         u8 isr;
 214
 215         for (i = 0; i < 1000; i++) {
 216                 isr = kw_read_reg(reg_isr) & KW_I2C_IRQ_MASK;
 217                 if (isr != 0)
 218                         return isr;
 219
 220                 /* This code is used with the timebase frozen, we cannot rely
 221                  * on udelay nor schedule when in polled mode !
 222                  * For now, just use a bogus loop....
 223                  */
 224                 if (host->polled) {
 225                         for (j = 1; j < 100000; j++)
 226                                 mb();
 227                 } else
 228                         msleep(1);
 229         }
 230         return isr;
 231 }
 232
 233 static void kw_i2c_do_stop(struct pmac_i2c_host_kw *host, int result)
 234 {
 235         kw_write_reg(reg_control, KW_I2C_CTL_STOP);
 236         host->state = state_stop;
 237         host->result = result;
 238 }
 239
 240
 241 static void kw_i2c_handle_interrupt(struct pmac_i2c_host_kw *host, u8 isr)
 242 {
 243         u8 ack;
 244
 245         DBG_LOW("kw_handle_interrupt(%s, isr: %x)\n",
 246                 __kw_state_names[host->state], isr);
 247
 248         if (host->state == state_idle) {
 249                 printk(KERN_WARNING "low_i2c: Keywest got an out of state"
 250                        " interrupt, ignoring\n");
 251                 kw_write_reg(reg_isr, isr);
 252                 return;
 253         }
 254
 255         if (isr == 0) {
 256                 printk(KERN_WARNING "low_i2c: Timeout in i2c transfer"
 257                        " on keywest !\n");
 258                 if (host->state != state_stop) {
 259                         kw_i2c_do_stop(host, -EIO);
 260                         return;
 261                 }
 262                 ack = kw_read_reg(reg_status);
 263                 if (ack & KW_I2C_STAT_BUSY)
 264                         kw_write_reg(reg_status, 0);
 265                 host->state = state_idle;
 266                 kw_write_reg(reg_ier, 0x00);
 267                 if (!host->polled)
 268                         complete(&host->complete);
 269                 return;
 270         }
 271
 272         if (isr & KW_I2C_IRQ_ADDR) {
 273                 ack = kw_read_reg(reg_status);
 274                 if (host->state != state_addr) {
 275                         WRONG_STATE("KW_I2C_IRQ_ADDR");
 276                         kw_i2c_do_stop(host, -EIO);
 277                 }
 278                 if ((ack & KW_I2C_STAT_LAST_AAK) == 0) {
 279                         host->result = -ENXIO;
 280                         host->state = state_stop;
 281                         DBG_LOW("KW: NAK on address\n");
 282                 } else {
 283                         if (host->len == 0)
 284                                 kw_i2c_do_stop(host, 0);
 285                         else if (host->rw) {
 286                                 host->state = state_read;
 287                                 if (host->len > 1)
 288                                         kw_write_reg(reg_control,
 289                                                      KW_I2C_CTL_AAK);
 290                         } else {
 291                                 host->state = state_write;
 292                                 kw_write_reg(reg_data, *(host->data++));
 293                                 host->len--;
 294                         }
 295                 }
 296                 kw_write_reg(reg_isr, KW_I2C_IRQ_ADDR);
 297         }
 298
 299         if (isr & KW_I2C_IRQ_DATA) {
 300                 if (host->state == state_read) {
 301                         *(host->data++) = kw_read_reg(reg_data);
 302                         host->len--;
 303                         kw_write_reg(reg_isr, KW_I2C_IRQ_DATA);
 304                         if (host->len == 0)
 305                                 host->state = state_stop;
 306                         else if (host->len == 1)
 307                                 kw_write_reg(reg_control, 0);
 308                 } else if (host->state == state_write) {
 309                         ack = kw_read_reg(reg_status);
 310                         if ((ack & KW_I2C_STAT_LAST_AAK) == 0) {
 311                                 DBG_LOW("KW: nack on data write\n");
 312                                 host->result = -EFBIG;
 313                                 host->state = state_stop;
 314                         } else if (host->len) {
 315                                 kw_write_reg(reg_data, *(host->data++));
 316                                 host->len--;
 317                         } else
 318                                 kw_i2c_do_stop(host, 0);
 319                 } else {
 320                         WRONG_STATE("KW_I2C_IRQ_DATA");
 321                         if (host->state != state_stop)
 322                                 kw_i2c_do_stop(host, -EIO);
 323                 }
 324                 kw_write_reg(reg_isr, KW_I2C_IRQ_DATA);
 325         }
 326
 327         if (isr & KW_I2C_IRQ_STOP) {
 328                 kw_write_reg(reg_isr, KW_I2C_IRQ_STOP);
 329                 if (host->state != state_stop) {
 330                         WRONG_STATE("KW_I2C_IRQ_STOP");
 331                         host->result = -EIO;
 332                 }
 333                 host->state = state_idle;
 334                 if (!host->polled)
 335                         complete(&host->complete);
 336         }
 337
 338         /* Below should only happen in manual mode which we don't use ... */
 339         if (isr & KW_I2C_IRQ_START)
 340                 kw_write_reg(reg_isr, KW_I2C_IRQ_START);
 341
 342 }
 343
 344 /* Interrupt handler */
 345 static irqreturn_t kw_i2c_irq(int irq, void *dev_id, struct pt_regs *regs)
 346 {
 347         struct pmac_i2c_host_kw *host = dev_id;
 348         unsigned long flags;
 349
 350         spin_lock_irqsave(&host->lock, flags);
 351         del_timer(&host->timeout_timer);
 352         kw_i2c_handle_interrupt(host, kw_read_reg(reg_isr));
 353         if (host->state != state_idle) {
 354                 host->timeout_timer.expires = jiffies + KW_POLL_TIMEOUT;
 355                 add_timer(&host->timeout_timer);
 356         }
 357         spin_unlock_irqrestore(&host->lock, flags);
 358         return IRQ_HANDLED;
 359 }
 360
 361 static void kw_i2c_timeout(unsigned long data)
 362 {
 363         struct pmac_i2c_host_kw *host = (struct pmac_i2c_host_kw *)data;
 364         unsigned long flags;
 365
 366         spin_lock_irqsave(&host->lock, flags);
 367         kw_i2c_handle_interrupt(host, kw_read_reg(reg_isr));
 368         if (host->state != state_idle) {
 369                 host->timeout_timer.expires = jiffies + KW_POLL_TIMEOUT;
 370                 add_timer(&host->timeout_timer);
 371         }
 372         spin_unlock_irqrestore(&host->lock, flags);
 373 }
 374
 375 static int kw_i2c_open(struct pmac_i2c_bus *bus)
 376 {
 377         struct pmac_i2c_host_kw *host = bus->hostdata;
 378         down(&host->mutex);
 379         return 0;
 380 }
 381
 382 static void kw_i2c_close(struct pmac_i2c_bus *bus)
 383 {
 384         struct pmac_i2c_host_kw *host = bus->hostdata;
 385         up(&host->mutex);
 386 }
 387
 388 static int kw_i2c_xfer(struct pmac_i2c_bus *bus, u8 addrdir, int subsize,
 389                        u32 subaddr, u8 *data, int len)
 390 {
 391         struct pmac_i2c_host_kw *host = bus->hostdata;
 392         u8 mode_reg = host->speed;
 393         int use_irq = host->irq != NO_IRQ && !bus->polled;
 394
 395         /* Setup mode & subaddress if any */
 396         switch(bus->mode) {
 397         case pmac_i2c_mode_dumb:
 398                 return -EINVAL;
 399         case pmac_i2c_mode_std:
 400                 mode_reg |= KW_I2C_MODE_STANDARD;
 401                 if (subsize != 0)
 402                         return -EINVAL;
 403                 break;
 404         case pmac_i2c_mode_stdsub:
 405                 mode_reg |= KW_I2C_MODE_STANDARDSUB;
 406                 if (subsize != 1)
 407                         return -EINVAL;
 408                 break;
 409         case pmac_i2c_mode_combined:
 410                 mode_reg |= KW_I2C_MODE_COMBINED;
 411                 if (subsize != 1)
 412                         return -EINVAL;
 413                 break;
 414         }
 415
 416         /* Setup channel & clear pending irqs */
 417         kw_write_reg(reg_isr, kw_read_reg(reg_isr));
 418         kw_write_reg(reg_mode, mode_reg | (bus->channel << 4));
 419         kw_write_reg(reg_status, 0);
 420
 421         /* Set up address and r/w bit, strip possible stale bus number from
 422          * address top bits
 423          */
 424         kw_write_reg(reg_addr, addrdir & 0xff);
 425
 426         /* Set up the sub address */
 427         if ((mode_reg & KW_I2C_MODE_MODE_MASK) == KW_I2C_MODE_STANDARDSUB
 428             || (mode_reg & KW_I2C_MODE_MODE_MASK) == KW_I2C_MODE_COMBINED)
 429                 kw_write_reg(reg_subaddr, subaddr);
 430
 431         /* Prepare for async operations */
 432         host->data = data;
 433         host->len = len;
 434         host->state = state_addr;
 435         host->result = 0;
 436         host->rw = (addrdir & 1);
 437         host->polled = bus->polled;
 438
 439         /* Enable interrupt if not using polled mode and interrupt is
 440          * available
 441          */
 442         if (use_irq) {
 443                 /* Clear completion */
 444                 INIT_COMPLETION(host->complete);
 445                 /* Ack stale interrupts */
 446                 kw_write_reg(reg_isr, kw_read_reg(reg_isr));
 447                 /* Arm timeout */
 448                 host->timeout_timer.expires = jiffies + KW_POLL_TIMEOUT;
 449                 add_timer(&host->timeout_timer);
 450                 /* Enable emission */
 451                 kw_write_reg(reg_ier, KW_I2C_IRQ_MASK);
 452         }
 453
 454         /* Start sending address */
 455         kw_write_reg(reg_control, KW_I2C_CTL_XADDR);
 456
 457         /* Wait for completion */
 458         if (use_irq)
 459                 wait_for_completion(&host->complete);
 460         else {
 461                 while(host->state != state_idle) {
 462                         unsigned long flags;
 463
 464                         u8 isr = kw_i2c_wait_interrupt(host);
 465                         spin_lock_irqsave(&host->lock, flags);
 466                         kw_i2c_handle_interrupt(host, isr);
 467                         spin_unlock_irqrestore(&host->lock, flags);
 468                 }
 469         }
 470
 471         /* Disable emission */
 472         kw_write_reg(reg_ier, 0);
 473
 474         return host->result;
 475 }
 476
 477 static struct pmac_i2c_host_kw *__init kw_i2c_host_init(struct device_node *np)
 478 {
 479         struct pmac_i2c_host_kw *host;
 480         u32                     *psteps, *prate, *addrp, steps;
 481
 482         host = kzalloc(sizeof(struct pmac_i2c_host_kw), GFP_KERNEL);
 483         if (host == NULL) {
 484                 printk(KERN_ERR "low_i2c: Can't allocate host for %s\n",
 485                        np->full_name);
 486                 return NULL;
 487         }
 488
 489         /* Apple is kind enough to provide a valid AAPL,address property
 490          * on all i2c keywest nodes so far ... we would have to fallback
 491          * to macio parsing if that wasn't the case
 492          */
 493         addrp = (u32 *)get_property(np, "AAPL,address", NULL);
 494         if (addrp == NULL) {
 495                 printk(KERN_ERR "low_i2c: Can't find address for %s\n",
 496                        np->full_name);
 497                 kfree(host);
 498                 return NULL;
 499         }
 500         init_MUTEX(&host->mutex);
 501         init_completion(&host->complete);
 502         spin_lock_init(&host->lock);
 503         init_timer(&host->timeout_timer);
 504         host->timeout_timer.function = kw_i2c_timeout;
 505         host->timeout_timer.data = (unsigned long)host;
 506
 507         psteps = (u32 *)get_property(np, "AAPL,address-step", NULL);
 508         steps = psteps ? (*psteps) : 0x10;
 509         for (host->bsteps = 0; (steps & 0x01) == 0; host->bsteps++)
 510                 steps >>= 1;
 511         /* Select interface rate */
 512         host->speed = KW_I2C_MODE_25KHZ;
 513         prate = (u32 *)get_property(np, "AAPL,i2c-rate", NULL);
 514         if (prate) switch(*prate) {
 515         case 100:
 516                 host->speed = KW_I2C_MODE_100KHZ;
 517                 break;
 518         case 50:
 519                 host->speed = KW_I2C_MODE_50KHZ;
 520                 break;
 521         case 25:
 522                 host->speed = KW_I2C_MODE_25KHZ;
 523                 break;
 524         }
 525         if (np->n_intrs > 0)
 526                 host->irq = np->intrs[0].line;
 527         else
 528                 host->irq = NO_IRQ;
 529
 530         host->base = ioremap((*addrp), 0x1000);
 531         if (host->base == NULL) {
 532                 printk(KERN_ERR "low_i2c: Can't map registers for %s\n",
 533                        np->full_name);
 534                 kfree(host);
 535                 return NULL;
 536         }
 537
 538         /* Make sure IRQ is disabled */
 539         kw_write_reg(reg_ier, 0);
 540
 541         /* Request chip interrupt */
 542         if (request_irq(host->irq, kw_i2c_irq, 0, "keywest i2c", host))
 543                 host->irq = NO_IRQ;
 544
 545         printk(KERN_INFO "KeyWest i2c @0x%08x irq %d %s\n",
 546                *addrp, host->irq, np->full_name);
 547
 548         return host;
 549 }
 550
 551
 552 static void __init kw_i2c_add(struct pmac_i2c_host_kw *host,
 553                               struct device_node *controller,
 554                               struct device_node *busnode,
 555                               int channel)
 556 {
 557         struct pmac_i2c_bus *bus;
 558
 559         bus = kzalloc(sizeof(struct pmac_i2c_bus), GFP_KERNEL);
 560         if (bus == NULL)
 561                 return;
 562
 563         bus->controller = of_node_get(controller);
 564         bus->busnode = of_node_get(busnode);
 565         bus->type = pmac_i2c_bus_keywest;
 566         bus->hostdata = host;
 567         bus->channel = channel;
 568         bus->mode = pmac_i2c_mode_std;
 569         bus->open = kw_i2c_open;
 570         bus->close = kw_i2c_close;
 571         bus->xfer = kw_i2c_xfer;
 572         init_MUTEX(&bus->sem);
 573         if (controller == busnode)
 574                 bus->flags = pmac_i2c_multibus;
 575         list_add(&bus->link, &pmac_i2c_busses);
 576
 577         printk(KERN_INFO " channel %d bus %s\n", channel,
 578                (controller == busnode) ? "<multibus>" : busnode->full_name);
 579 }
 580
 581 static void __init kw_i2c_probe(void)
 582 {
 583         struct device_node *np, *child, *parent;
 584
 585         /* Probe keywest-i2c busses */
 586         for (np = NULL;
 587              (np = of_find_compatible_node(np, "i2c","keywest-i2c")) != NULL;){
 588                 struct pmac_i2c_host_kw *host;
 589                 int multibus, chans, i;
 590
 591                 /* Found one, init a host structure */
 592                 host = kw_i2c_host_init(np);
 593                 if (host == NULL)
 594                         continue;
 595
 596                 /* Now check if we have a multibus setup (old style) or if we
 597                  * have proper bus nodes. Note that the "new" way (proper bus
 598                  * nodes) might cause us to not create some busses that are
 599                  * kept hidden in the device-tree. In the future, we might
 600                  * want to work around that by creating busses without a node
 601                  * but not for now
 602                  */
 603                 child = of_get_next_child(np, NULL);
 604                 multibus = !child || strcmp(child->name, "i2c-bus");
 605                 of_node_put(child);
 606
 607                 /* For a multibus setup, we get the bus count based on the
 608                  * parent type
 609                  */
 610                 if (multibus) {
 611                         parent = of_get_parent(np);
 612                         if (parent == NULL)
 613                                 continue;
 614                         chans = parent->name[0] == 'u' ? 2 : 1;
 615                         for (i = 0; i < chans; i++)
 616                                 kw_i2c_add(host, np, np, i);
 617                 } else {
 618                         for (child = NULL;
 619                              (child = of_get_next_child(np, child)) != NULL;) {
 620                                 u32 *reg =
 621                                         (u32 *)get_property(child, "reg", NULL);
 622                                 if (reg == NULL)
 623                                         continue;
 624                                 kw_i2c_add(host, np, child, *reg);
 625                         }
 626                 }
 627         }
 628 }
 629
 630
 631 /*
 632  *
 633  * PMU implementation
 634  *
 635  */
 636
 637 #ifdef CONFIG_ADB_PMU
 638
 639 /*
 640  * i2c command block to the PMU
 641  */
 642 struct pmu_i2c_hdr {
 643         u8      bus;
 644         u8      mode;
 645         u8      bus2;
 646         u8      address;
 647         u8      sub_addr;
 648         u8      comb_addr;
 649         u8      count;
 650         u8      data[];
 651 };
 652
 653 static void pmu_i2c_complete(struct adb_request *req)
 654 {
 655         complete(req->arg);
 656 }
 657
 658 static int pmu_i2c_xfer(struct pmac_i2c_bus *bus, u8 addrdir, int subsize,
 659                         u32 subaddr, u8 *data, int len)
 660 {
 661         struct adb_request *req = bus->hostdata;
 662         struct pmu_i2c_hdr *hdr = (struct pmu_i2c_hdr *)&req->data[1];
 663         struct completion comp;
 664         int read = addrdir & 1;
 665         int retry;
 666         int rc = 0;
 667
 668         /* For now, limit ourselves to 16 bytes transfers */
 669         if (len > 16)
 670                 return -EINVAL;
 671
 672         init_completion(&comp);
 673
 674         for (retry = 0; retry < 16; retry++) {
 675                 memset(req, 0, sizeof(struct adb_request));
 676                 hdr->bus = bus->channel;
 677                 hdr->count = len;
 678
 679                 switch(bus->mode) {
 680                 case pmac_i2c_mode_std:
 681                         if (subsize != 0)
 682                                 return -EINVAL;
 683                         hdr->address = addrdir;
 684                         hdr->mode = PMU_I2C_MODE_SIMPLE;
 685                         break;
 686                 case pmac_i2c_mode_stdsub:
 687                 case pmac_i2c_mode_combined:
 688                         if (subsize != 1)
 689                                 return -EINVAL;
 690                         hdr->address = addrdir & 0xfe;
 691                         hdr->comb_addr = addrdir;
 692                         hdr->sub_addr = subaddr;
 693                         if (bus->mode == pmac_i2c_mode_stdsub)
 694                                 hdr->mode = PMU_I2C_MODE_STDSUB;
 695                         else
 696                                 hdr->mode = PMU_I2C_MODE_COMBINED;
 697                         break;
 698                 default:
 699                         return -EINVAL;
 700                 }
 701
 702                 INIT_COMPLETION(comp);
 703                 req->data[0] = PMU_I2C_CMD;
 704                 req->reply[0] = 0xff;
 705                 req->nbytes = sizeof(struct pmu_i2c_hdr) + 1;
 706                 req->done = pmu_i2c_complete;
 707                 req->arg = &comp;
 708                 if (!read && len) {
 709                         memcpy(hdr->data, data, len);
 710                         req->nbytes += len;
 711                 }
 712                 rc = pmu_queue_request(req);
 713                 if (rc)
 714                         return rc;
 715                 wait_for_completion(&comp);
 716                 if (req->reply[0] == PMU_I2C_STATUS_OK)
 717                         break;
 718                 msleep(15);
 719         }
 720         if (req->reply[0] != PMU_I2C_STATUS_OK)
 721                 return -EIO;
 722
 723         for (retry = 0; retry < 16; retry++) {
 724                 memset(req, 0, sizeof(struct adb_request));
 725
 726                 /* I know that looks like a lot, slow as hell, but darwin
 727                  * does it so let's be on the safe side for now
 728                  */
 729                 msleep(15);
 730
 731                 hdr->bus = PMU_I2C_BUS_STATUS;
 732
 733                 INIT_COMPLETION(comp);
 734                 req->data[0] = PMU_I2C_CMD;
 735                 req->reply[0] = 0xff;
 736                 req->nbytes = 2;
 737                 req->done = pmu_i2c_complete;
 738                 req->arg = &comp;
 739                 rc = pmu_queue_request(req);
 740                 if (rc)
 741                         return rc;
 742                 wait_for_completion(&comp);
 743
 744                 if (req->reply[0] == PMU_I2C_STATUS_OK && !read)
 745                         return 0;
 746                 if (req->reply[0] == PMU_I2C_STATUS_DATAREAD && read) {
 747                         int rlen = req->reply_len - 1;
 748
 749                         if (rlen != len) {
 750                                 printk(KERN_WARNING "low_i2c: PMU returned %d"
 751                                        " bytes, expected %d !\n", rlen, len);
 752                                 return -EIO;
 753                         }
 754                         if (len)
 755                                 memcpy(data, &req->reply[1], len);
 756                         return 0;
 757                 }
 758         }
 759         return -EIO;
 760 }
 761
 762 static void __init pmu_i2c_probe(void)
 763 {
 764         struct pmac_i2c_bus *bus;
 765         struct device_node *busnode;
 766         int channel, sz;
 767
 768         if (!pmu_present())
 769                 return;
 770
 771         /* There might or might not be a "pmu-i2c" node, we use that
 772          * or via-pmu itself, whatever we find. I haven't seen a machine
 773          * with separate bus nodes, so we assume a multibus setup
 774          */
 775         busnode = of_find_node_by_name(NULL, "pmu-i2c");
 776         if (busnode == NULL)
 777                 busnode = of_find_node_by_name(NULL, "via-pmu");
 778         if (busnode == NULL)
 779                 return;
 780
 781         printk(KERN_INFO "PMU i2c %s\n", busnode->full_name);
 782
 783         /*
 784          * We add bus 1 and 2 only for now, bus 0 is "special"
 785          */
 786         for (channel = 1; channel <= 2; channel++) {
 787                 sz = sizeof(struct pmac_i2c_bus) + sizeof(struct adb_request);
 788                 bus = kzalloc(sz, GFP_KERNEL);
 789                 if (bus == NULL)
 790                         return;
 791
 792                 bus->controller = busnode;
 793                 bus->busnode = busnode;
 794                 bus->type = pmac_i2c_bus_pmu;
 795                 bus->channel = channel;
 796                 bus->mode = pmac_i2c_mode_std;
 797                 bus->hostdata = bus + 1;
 798                 bus->xfer = pmu_i2c_xfer;
 799                 init_MUTEX(&bus->sem);
 800                 bus->flags = pmac_i2c_multibus;
 801                 list_add(&bus->link, &pmac_i2c_busses);
 802
 803                 printk(KERN_INFO " channel %d bus <multibus>\n", channel);
 804         }
 805 }
 806
 807 #endif /* CONFIG_ADB_PMU */
 808
 809
 810 /*
 811  *
 812  * SMU implementation
 813  *
 814  */
 815
 816 #ifdef CONFIG_PMAC_SMU
 817
 818 static void smu_i2c_complete(struct smu_i2c_cmd *cmd, void *misc)
 819 {
 820         complete(misc);
 821 }
 822
 823 static int smu_i2c_xfer(struct pmac_i2c_bus *bus, u8 addrdir, int subsize,
 824                         u32 subaddr, u8 *data, int len)
 825 {
 826         struct smu_i2c_cmd *cmd = bus->hostdata;
 827         struct completion comp;
 828         int read = addrdir & 1;
 829         int rc = 0;
 830
 831         if ((read && len > SMU_I2C_READ_MAX) ||
 832             ((!read) && len > SMU_I2C_WRITE_MAX))
 833                 return -EINVAL;
 834
 835         memset(cmd, 0, sizeof(struct smu_i2c_cmd));
 836         cmd->info.bus = bus->channel;
 837         cmd->info.devaddr = addrdir;
 838         cmd->info.datalen = len;
 839
 840         switch(bus->mode) {
 841         case pmac_i2c_mode_std:
 842                 if (subsize != 0)
 843                         return -EINVAL;
 844                 cmd->info.type = SMU_I2C_TRANSFER_SIMPLE;
 845                 break;
 846         case pmac_i2c_mode_stdsub:
 847         case pmac_i2c_mode_combined:
 848                 if (subsize > 3 || subsize < 1)
 849                         return -EINVAL;
 850                 cmd->info.sublen = subsize;
 851                 /* that's big-endian only but heh ! */
 852                 memcpy(&cmd->info.subaddr, ((char *)&subaddr) + (4 - subsize),
 853                        subsize);
 854                 if (bus->mode == pmac_i2c_mode_stdsub)
 855                         cmd->info.type = SMU_I2C_TRANSFER_STDSUB;
 856                 else
 857                         cmd->info.type = SMU_I2C_TRANSFER_COMBINED;
 858                 break;
 859         default:
 860                 return -EINVAL;
 861         }
 862         if (!read && len)
 863                 memcpy(cmd->info.data, data, len);
 864
 865         init_completion(&comp);
 866         cmd->done = smu_i2c_complete;
 867         cmd->misc = &comp;
 868         rc = smu_queue_i2c(cmd);
 869         if (rc < 0)
 870                 return rc;
 871         wait_for_completion(&comp);
 872         rc = cmd->status;
 873
 874         if (read && len)
 875                 memcpy(data, cmd->info.data, len);
 876         return rc < 0 ? rc : 0;
 877 }
 878
 879 static void __init smu_i2c_probe(void)
 880 {
 881         struct device_node *controller, *busnode;
 882         struct pmac_i2c_bus *bus;
 883         u32 *reg;
 884         int sz;
 885
 886         if (!smu_present())
 887                 return;
 888
 889         controller = of_find_node_by_name(NULL, "smu-i2c-control");
 890         if (controller == NULL)
 891                 controller = of_find_node_by_name(NULL, "smu");
 892         if (controller == NULL)
 893                 return;
 894
 895         printk(KERN_INFO "SMU i2c %s\n", controller->full_name);
 896
 897         /* Look for childs, note that they might not be of the right
 898          * type as older device trees mix i2c busses and other thigns
 899          * at the same level
 900          */
 901         for (busnode = NULL;
 902              (busnode = of_get_next_child(controller, busnode)) != NULL;) {
 903                 if (strcmp(busnode->type, "i2c") &&
 904                     strcmp(busnode->type, "i2c-bus"))
 905                         continue;
 906                 reg = (u32 *)get_property(busnode, "reg", NULL);
 907                 if (reg == NULL)
 908                         continue;
 909
 910                 sz = sizeof(struct pmac_i2c_bus) + sizeof(struct smu_i2c_cmd);
 911                 bus = kzalloc(sz, GFP_KERNEL);
 912                 if (bus == NULL)
 913                         return;
 914
 915                 bus->controller = controller;
 916                 bus->busnode = of_node_get(busnode);
 917                 bus->type = pmac_i2c_bus_smu;
 918                 bus->channel = *reg;
 919                 bus->mode = pmac_i2c_mode_std;
 920                 bus->hostdata = bus + 1;
 921                 bus->xfer = smu_i2c_xfer;
 922                 init_MUTEX(&bus->sem);
 923                 bus->flags = 0;
 924                 list_add(&bus->link, &pmac_i2c_busses);
 925
 926                 printk(KERN_INFO " channel %x bus %s\n",
 927                        bus->channel, busnode->full_name);
 928         }
 929 }
 930
 931 #endif /* CONFIG_PMAC_SMU */
 932
 933 /*
 934  *
 935  * Core code
 936  *
 937  */
 938
 939
 940 struct pmac_i2c_bus *pmac_i2c_find_bus(struct device_node *node)
 941 {
 942         struct device_node *p = of_node_get(node);
 943         struct device_node *prev = NULL;
 944         struct pmac_i2c_bus *bus;
 945
 946         while(p) {
 947                 list_for_each_entry(bus, &pmac_i2c_busses, link) {
 948                         if (p == bus->busnode) {
 949                                 if (prev && bus->flags & pmac_i2c_multibus) {
 950                                         u32 *reg;
 951                                         reg = (u32 *)get_property(prev, "reg",
 952                                                                   NULL);
 953                                         if (!reg)
 954                                                 continue;
 955                                         if (((*reg) >> 8) != bus->channel)
 956                                                 continue;
 957                                 }
 958                                 of_node_put(p);
 959                                 of_node_put(prev);
 960                                 return bus;
 961                         }
 962                 }
 963                 of_node_put(prev);
 964                 prev = p;
 965                 p = of_get_parent(p);
 966         }
 967         return NULL;
 968 }
 969 EXPORT_SYMBOL_GPL(pmac_i2c_find_bus);
 970
 971 u8 pmac_i2c_get_dev_addr(struct device_node *device)
 972 {
 973         u32 *reg = (u32 *)get_property(device, "reg", NULL);
 974
 975         if (reg == NULL)
 976                 return 0;
 977
 978         return (*reg) & 0xff;
 979 }
 980 EXPORT_SYMBOL_GPL(pmac_i2c_get_dev_addr);
 981
 982 struct device_node *pmac_i2c_get_controller(struct pmac_i2c_bus *bus)
 983 {
 984         return bus->controller;
 985 }
 986 EXPORT_SYMBOL_GPL(pmac_i2c_get_controller);
 987
 988 struct device_node *pmac_i2c_get_bus_node(struct pmac_i2c_bus *bus)
 989 {
 990         return bus->busnode;
 991 }
 992 EXPORT_SYMBOL_GPL(pmac_i2c_get_bus_node);
 993
 994 int pmac_i2c_get_type(struct pmac_i2c_bus *bus)
 995 {
 996         return bus->type;
 997 }
 998 EXPORT_SYMBOL_GPL(pmac_i2c_get_type);
 999
1000 int pmac_i2c_get_flags(struct pmac_i2c_bus *bus)
1001 {
1002         return bus->flags;
1003 }
1004 EXPORT_SYMBOL_GPL(pmac_i2c_get_flags);
1005
1006 int pmac_i2c_get_channel(struct pmac_i2c_bus *bus)
1007 {
1008         return bus->channel;
1009 }
1010 EXPORT_SYMBOL_GPL(pmac_i2c_get_channel);
1011
1012
1013 void pmac_i2c_attach_adapter(struct pmac_i2c_bus *bus,
1014                              struct i2c_adapter *adapter)
1015 {
1016         WARN_ON(bus->adapter != NULL);
1017         bus->adapter = adapter;
1018 }
1019 EXPORT_SYMBOL_GPL(pmac_i2c_attach_adapter);
1020
1021 void pmac_i2c_detach_adapter(struct pmac_i2c_bus *bus,
1022                              struct i2c_adapter *adapter)
1023 {
1024         WARN_ON(bus->adapter != adapter);
1025         bus->adapter = NULL;
1026 }
1027 EXPORT_SYMBOL_GPL(pmac_i2c_detach_adapter);
1028
1029 struct i2c_adapter *pmac_i2c_get_adapter(struct pmac_i2c_bus *bus)
1030 {
1031         return bus->adapter;
1032 }
1033 EXPORT_SYMBOL_GPL(pmac_i2c_get_adapter);
1034
1035 struct pmac_i2c_bus *pmac_i2c_adapter_to_bus(struct i2c_adapter *adapter)
1036 {
1037         struct pmac_i2c_bus *bus;
1038
1039         list_for_each_entry(bus, &pmac_i2c_busses, link)
1040                 if (bus->adapter == adapter)
1041                         return bus;
1042         return NULL;
1043 }
1044 EXPORT_SYMBOL_GPL(pmac_i2c_adapter_to_bus);
1045
1046 int pmac_i2c_match_adapter(struct device_node *dev, struct i2c_adapter *adapter)
1047 {
1048         struct pmac_i2c_bus *bus = pmac_i2c_find_bus(dev);
1049
1050         if (bus == NULL)
1051                 return 0;
1052         return (bus->adapter == adapter);
1053 }
1054 EXPORT_SYMBOL_GPL(pmac_i2c_match_adapter);
1055
1056 int pmac_low_i2c_lock(struct device_node *np)
1057 {
1058         struct pmac_i2c_bus *bus, *found = NULL;
1059
1060         list_for_each_entry(bus, &pmac_i2c_busses, link) {
1061                 if (np == bus->controller) {
1062                         found = bus;
1063                         break;
1064                 }
1065         }
1066         if (!found)
1067                 return -ENODEV;
1068         return pmac_i2c_open(bus, 0);
1069 }
1070 EXPORT_SYMBOL_GPL(pmac_low_i2c_lock);
1071
1072 int pmac_low_i2c_unlock(struct device_node *np)
1073 {
1074         struct pmac_i2c_bus *bus, *found = NULL;
1075
1076         list_for_each_entry(bus, &pmac_i2c_busses, link) {
1077                 if (np == bus->controller) {
1078                         found = bus;
1079                         break;
1080                 }
1081         }
1082         if (!found)
1083                 return -ENODEV;
1084         pmac_i2c_close(bus);
1085         return 0;
1086 }
1087 EXPORT_SYMBOL_GPL(pmac_low_i2c_unlock);
1088
1089
1090 int pmac_i2c_open(struct pmac_i2c_bus *bus, int polled)
1091 {
1092         int rc;
1093
1094         down(&bus->sem);
1095         bus->polled = polled || pmac_i2c_force_poll;
1096         bus->opened = 1;
1097         bus->mode = pmac_i2c_mode_std;
1098         if (bus->open && (rc = bus->open(bus)) != 0) {
1099                 bus->opened = 0;
1100                 up(&bus->sem);
1101                 return rc;
1102         }
1103         return 0;
1104 }
1105 EXPORT_SYMBOL_GPL(pmac_i2c_open);
1106
1107 void pmac_i2c_close(struct pmac_i2c_bus *bus)
1108 {
1109         WARN_ON(!bus->opened);
1110         if (bus->close)
1111                 bus->close(bus);
1112         bus->opened = 0;
1113         up(&bus->sem);
1114 }
1115 EXPORT_SYMBOL_GPL(pmac_i2c_close);
1116
1117 int pmac_i2c_setmode(struct pmac_i2c_bus *bus, int mode)
1118 {
1119         WARN_ON(!bus->opened);
1120
1121         /* Report me if you see the error below as there might be a new
1122          * "combined4" mode that I need to implement for the SMU bus
1123          */
1124         if (mode < pmac_i2c_mode_dumb || mode > pmac_i2c_mode_combined) {
1125                 printk(KERN_ERR "low_i2c: Invalid mode %d requested on"
1126                        " bus %s !\n", mode, bus->busnode->full_name);
1127                 return -EINVAL;
1128         }
1129         bus->mode = mode;
1130
1131         return 0;
1132 }
1133 EXPORT_SYMBOL_GPL(pmac_i2c_setmode);
1134
1135 int pmac_i2c_xfer(struct pmac_i2c_bus *bus, u8 addrdir, int subsize,
1136                   u32 subaddr, u8 *data, int len)
1137 {
1138         int rc;
1139
1140         WARN_ON(!bus->opened);
1141
1142         DBG("xfer() chan=%d, addrdir=0x%x, mode=%d, subsize=%d, subaddr=0x%x,"
1143             " %d bytes, bus %s\n", bus->channel, addrdir, bus->mode, subsize,
1144             subaddr, len, bus->busnode->full_name);
1145
1146         rc = bus->xfer(bus, addrdir, subsize, subaddr, data, len);
1147
1148 #ifdef DEBUG
1149         if (rc)
1150                 DBG("xfer error %d\n", rc);
1151 #endif
1152         return rc;
1153 }
1154 EXPORT_SYMBOL_GPL(pmac_i2c_xfer);
1155
1156 /* some quirks for platform function decoding */
1157 enum {
1158         pmac_i2c_quirk_invmask = 0x00000001u,
1159         pmac_i2c_quirk_skip = 0x00000002u,
1160 };
1161
1162 static void pmac_i2c_devscan(void (*callback)(struct device_node *dev,
1163                                               int quirks))
1164 {
1165         struct pmac_i2c_bus *bus;
1166         struct device_node *np;
1167         static struct whitelist_ent {
1168                 char *name;
1169                 char *compatible;
1170                 int quirks;
1171         } whitelist[] = {
1172                 /* XXX Study device-tree's & apple drivers are get the quirks
1173                  * right !
1174                  */
1175                 /* Workaround: It seems that running the clockspreading
1176                  * properties on the eMac will cause lockups during boot.
1177                  * The machine seems to work fine without that. So for now,
1178                  * let's make sure i2c-hwclock doesn't match about "imic"
1179                  * clocks and we'll figure out if we really need to do
1180                  * something special about those later.
1181                  */
1182                 { "i2c-hwclock", "imic5002", pmac_i2c_quirk_skip },
1183                 { "i2c-hwclock", "imic5003", pmac_i2c_quirk_skip },
1184                 { "i2c-hwclock", NULL, pmac_i2c_quirk_invmask },
1185                 { "i2c-cpu-voltage", NULL, 0},
1186                 {  "temp-monitor", NULL, 0 },
1187                 {  "supply-monitor", NULL, 0 },
1188                 { NULL, NULL, 0 },
1189         };
1190
1191         /* Only some devices need to have platform functions instanciated
1192          * here. For now, we have a table. Others, like 9554 i2c GPIOs used
1193          * on Xserve, if we ever do a driver for them, will use their own
1194          * platform function instance
1195          */
1196         list_for_each_entry(bus, &pmac_i2c_busses, link) {
1197                 for (np = NULL;
1198                      (np = of_get_next_child(bus->busnode, np)) != NULL;) {
1199                         struct whitelist_ent *p;
1200                         /* If multibus, check if device is on that bus */
1201                         if (bus->flags & pmac_i2c_multibus)
1202                                 if (bus != pmac_i2c_find_bus(np))
1203                                         continue;
1204                         for (p = whitelist; p->name != NULL; p++) {
1205                                 if (strcmp(np->name, p->name))
1206                                         continue;
1207                                 if (p->compatible &&
1208                                     !device_is_compatible(np, p->compatible))
1209                                         continue;
1210                                 if (p->quirks & pmac_i2c_quirk_skip)
1211                                         break;
1212                                 callback(np, p->quirks);
1213                                 break;
1214                         }
1215                 }
1216         }
1217 }
1218
1219 #define MAX_I2C_DATA    64
1220
1221 struct pmac_i2c_pf_inst
1222 {
1223         struct pmac_i2c_bus     *bus;
1224         u8                      addr;
1225         u8                      buffer[MAX_I2C_DATA];
1226         u8                      scratch[MAX_I2C_DATA];
1227         int                     bytes;
1228         int                     quirks;
1229 };
1230
1231 static void* pmac_i2c_do_begin(struct pmf_function *func, struct pmf_args *args)
1232 {
1233         struct pmac_i2c_pf_inst *inst;
1234         struct pmac_i2c_bus     *bus;
1235
1236         bus = pmac_i2c_find_bus(func->node);
1237         if (bus == NULL) {
1238                 printk(KERN_ERR "low_i2c: Can't find bus for %s (pfunc)\n",
1239                        func->node->full_name);
1240                 return NULL;
1241         }
1242         if (pmac_i2c_open(bus, 0)) {
1243                 printk(KERN_ERR "low_i2c: Can't open i2c bus for %s (pfunc)\n",
1244                        func->node->full_name);
1245                 return NULL;
1246         }
1247
1248         /* XXX might need GFP_ATOMIC when called during the suspend process,
1249          * but then, there are already lots of issues with suspending when
1250          * near OOM that need to be resolved, the allocator itself should
1251          * probably make GFP_NOIO implicit during suspend
1252          */
1253         inst = kzalloc(sizeof(struct pmac_i2c_pf_inst), GFP_KERNEL);
1254         if (inst == NULL) {
1255                 pmac_i2c_close(bus);
1256                 return NULL;
1257         }
1258         inst->bus = bus;
1259         inst->addr = pmac_i2c_get_dev_addr(func->node);
1260         inst->quirks = (int)(long)func->driver_data;
1261         return inst;
1262 }
1263
1264 static void pmac_i2c_do_end(struct pmf_function *func, void *instdata)
1265 {
1266         struct pmac_i2c_pf_inst *inst = instdata;
1267
1268         if (inst == NULL)
1269                 return;
1270         pmac_i2c_close(inst->bus);
1271         if (inst)
1272                 kfree(inst);
1273 }
1274
1275 static int pmac_i2c_do_read(PMF_STD_ARGS, u32 len)
1276 {
1277         struct pmac_i2c_pf_inst *inst = instdata;
1278
1279         inst->bytes = len;
1280         return pmac_i2c_xfer(inst->bus, inst->addr | pmac_i2c_read, 0, 0,
1281                              inst->buffer, len);
1282 }
1283
1284 static int pmac_i2c_do_write(PMF_STD_ARGS, u32 len, const u8 *data)
1285 {
1286         struct pmac_i2c_pf_inst *inst = instdata;
1287
1288         return pmac_i2c_xfer(inst->bus, inst->addr | pmac_i2c_write, 0, 0,
1289                              (u8 *)data, len);
1290 }
1291
1292 /* This function is used to do the masking & OR'ing for the "rmw" type
1293  * callbacks. Ze should apply the mask and OR in the values in the
1294  * buffer before writing back. The problem is that it seems that
1295  * various darwin drivers implement the mask/or differently, thus
1296  * we need to check the quirks first
1297  */
1298 static void pmac_i2c_do_apply_rmw(struct pmac_i2c_pf_inst *inst,
1299                                   u32 len, const u8 *mask, const u8 *val)
1300 {
1301         int i;
1302
1303         if (inst->quirks & pmac_i2c_quirk_invmask) {
1304                 for (i = 0; i < len; i ++)
1305                         inst->scratch[i] = (inst->buffer[i] & mask[i]) | val[i];
1306         } else {
1307                 for (i = 0; i < len; i ++)
1308                         inst->scratch[i] = (inst->buffer[i] & ~mask[i])
1309                                 | (val[i] & mask[i]);
1310         }
1311 }
1312
1313 static int pmac_i2c_do_rmw(PMF_STD_ARGS, u32 masklen, u32 valuelen,
1314                            u32 totallen, const u8 *maskdata,
1315                            const u8 *valuedata)
1316 {
1317         struct pmac_i2c_pf_inst *inst = instdata;
1318
1319         if (masklen > inst->bytes || valuelen > inst->bytes ||
1320             totallen > inst->bytes || valuelen > masklen)
1321                 return -EINVAL;
1322
1323         pmac_i2c_do_apply_rmw(inst, masklen, maskdata, valuedata);
1324
1325         return pmac_i2c_xfer(inst->bus, inst->addr | pmac_i2c_write, 0, 0,
1326                              inst->scratch, totallen);
1327 }
1328
1329 static int pmac_i2c_do_read_sub(PMF_STD_ARGS, u8 subaddr, u32 len)
1330 {
1331         struct pmac_i2c_pf_inst *inst = instdata;
1332
1333         inst->bytes = len;
1334         return pmac_i2c_xfer(inst->bus, inst->addr | pmac_i2c_read, 1, subaddr,
1335                              inst->buffer, len);
1336 }
1337
1338 static int pmac_i2c_do_write_sub(PMF_STD_ARGS, u8 subaddr, u32 len,
1339                                      const u8 *data)
1340 {
1341         struct pmac_i2c_pf_inst *inst = instdata;
1342
1343         return pmac_i2c_xfer(inst->bus, inst->addr | pmac_i2c_write, 1,
1344                              subaddr, (u8 *)data, len);
1345 }
1346
1347 static int pmac_i2c_do_set_mode(PMF_STD_ARGS, int mode)
1348 {
1349         struct pmac_i2c_pf_inst *inst = instdata;
1350
1351         return pmac_i2c_setmode(inst->bus, mode);
1352 }
1353
1354 static int pmac_i2c_do_rmw_sub(PMF_STD_ARGS, u8 subaddr, u32 masklen,
1355                                u32 valuelen, u32 totallen, const u8 *maskdata,
1356                                const u8 *valuedata)
1357 {
1358         struct pmac_i2c_pf_inst *inst = instdata;
1359
1360         if (masklen > inst->bytes || valuelen > inst->bytes ||
1361             totallen > inst->bytes || valuelen > masklen)
1362                 return -EINVAL;
1363
1364         pmac_i2c_do_apply_rmw(inst, masklen, maskdata, valuedata);
1365
1366         return pmac_i2c_xfer(inst->bus, inst->addr | pmac_i2c_write, 1,
1367                              subaddr, inst->scratch, totallen);
1368 }
1369
1370 static int pmac_i2c_do_mask_and_comp(PMF_STD_ARGS, u32 len,
1371                                      const u8 *maskdata,
1372                                      const u8 *valuedata)
1373 {
1374         struct pmac_i2c_pf_inst *inst = instdata;
1375         int i, match;
1376
1377         /* Get return value pointer, it's assumed to be a u32 */
1378         if (!args || !args->count || !args->u[0].p)
1379                 return -EINVAL;
1380
1381         /* Check buffer */
1382         if (len > inst->bytes)
1383                 return -EINVAL;
1384
1385         for (i = 0, match = 1; match && i < len; i ++)
1386                 if ((inst->buffer[i] & maskdata[i]) != valuedata[i])
1387                         match = 0;
1388         *args->u[0].p = match;
1389         return 0;
1390 }
1391
1392 static int pmac_i2c_do_delay(PMF_STD_ARGS, u32 duration)
1393 {
1394         msleep((duration + 999) / 1000);
1395         return 0;
1396 }
1397
1398
1399 static struct pmf_handlers pmac_i2c_pfunc_handlers = {
1400         .begin                  = pmac_i2c_do_begin,
1401         .end                    = pmac_i2c_do_end,
1402         .read_i2c               = pmac_i2c_do_read,
1403         .write_i2c              = pmac_i2c_do_write,
1404         .rmw_i2c                = pmac_i2c_do_rmw,
1405         .read_i2c_sub           = pmac_i2c_do_read_sub,
1406         .write_i2c_sub          = pmac_i2c_do_write_sub,
1407         .rmw_i2c_sub            = pmac_i2c_do_rmw_sub,
1408         .set_i2c_mode           = pmac_i2c_do_set_mode,
1409         .mask_and_compare       = pmac_i2c_do_mask_and_comp,
1410         .delay                  = pmac_i2c_do_delay,
1411 };
1412
1413 static void __init pmac_i2c_dev_create(struct device_node *np, int quirks)
1414 {
1415         DBG("dev_create(%s)\n", np->full_name);
1416
1417         pmf_register_driver(np, &pmac_i2c_pfunc_handlers,
1418                             (void *)(long)quirks);
1419 }
1420
1421 static void __init pmac_i2c_dev_init(struct device_node *np, int quirks)
1422 {
1423         DBG("dev_create(%s)\n", np->full_name);
1424
1425         pmf_do_functions(np, NULL, 0, PMF_FLAGS_ON_INIT, NULL);
1426 }
1427
1428 static void pmac_i2c_dev_suspend(struct device_node *np, int quirks)
1429 {
1430         DBG("dev_suspend(%s)\n", np->full_name);
1431         pmf_do_functions(np, NULL, 0, PMF_FLAGS_ON_SLEEP, NULL);
1432 }
1433
1434 static void pmac_i2c_dev_resume(struct device_node *np, int quirks)
1435 {
1436         DBG("dev_resume(%s)\n", np->full_name);
1437         pmf_do_functions(np, NULL, 0, PMF_FLAGS_ON_WAKE, NULL);
1438 }
1439
1440 void pmac_pfunc_i2c_suspend(void)
1441 {
1442         pmac_i2c_devscan(pmac_i2c_dev_suspend);
1443 }
1444
1445 void pmac_pfunc_i2c_resume(void)
1446 {
1447         pmac_i2c_devscan(pmac_i2c_dev_resume);
1448 }
1449
1450 /*
1451  * Initialize us: probe all i2c busses on the machine, instantiate
1452  * busses and platform functions as needed.
1453  */
1454 /* This is non-static as it might be called early by smp code */
1455 int __init pmac_i2c_init(void)
1456 {
1457         static int i2c_inited;
1458
1459         if (i2c_inited)
1460                 return 0;
1461         i2c_inited = 1;
1462
1463         if (!machine_is(powermac))
1464                 return 0;
1465
1466         /* Probe keywest-i2c busses */
1467         kw_i2c_probe();
1468
1469 #ifdef CONFIG_ADB_PMU
1470         /* Probe PMU i2c busses */
1471         pmu_i2c_probe();
1472 #endif
1473
1474 #ifdef CONFIG_PMAC_SMU
1475         /* Probe SMU i2c busses */
1476         smu_i2c_probe();
1477 #endif
1478
1479         /* Now add plaform functions for some known devices */
1480         pmac_i2c_devscan(pmac_i2c_dev_create);
1481
1482         return 0;
1483 }
1484 arch_initcall(pmac_i2c_init);
1485
1486 /* Since pmac_i2c_init can be called too early for the platform device
1487  * registration, we need to do it at a later time. In our case, subsys
1488  * happens to fit well, though I agree it's a bit of a hack...
1489  */
1490 static int __init pmac_i2c_create_platform_devices(void)
1491 {
1492         struct pmac_i2c_bus *bus;
1493         int i = 0;
1494
1495         /* In the case where we are initialized from smp_init(), we must
1496          * not use the timer (and thus the irq). It's safe from now on
1497          * though
1498          */
1499         pmac_i2c_force_poll = 0;
1500
1501         /* Create platform devices */
1502         list_for_each_entry(bus, &pmac_i2c_busses, link) {
1503                 bus->platform_dev =
1504                         platform_device_alloc("i2c-powermac", i++);
1505                 if (bus->platform_dev == NULL)
1506                         return -ENOMEM;
1507                 bus->platform_dev->dev.platform_data = bus;
1508                 platform_device_add(bus->platform_dev);
1509         }
1510
1511         /* Now call platform "init" functions */
1512         pmac_i2c_devscan(pmac_i2c_dev_init);
1513
1514         return 0;
1515 }
1516 subsys_initcall(pmac_i2c_create_platform_devices);