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