Merge branch 'akpm'
[linux-2.6/next.git] / arch / powerpc / platforms / powermac / low_i2c.c
blob996c5ff7824b7b3342e1bce1ce46d44db06e8491
1 /*
2 * arch/powerpc/platforms/powermac/low_i2c.c
4 * Copyright (C) 2003-2005 Ben. Herrenschmidt (benh@kernel.crashing.org)
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.
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...
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.
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.
30 #undef DEBUG
31 #undef DEBUG_LOW
33 #include <linux/types.h>
34 #include <linux/sched.h>
35 #include <linux/init.h>
36 #include <linux/export.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>
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
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
73 static int pmac_i2c_force_poll = 1;
76 * A bus structure. Each bus in the system has such a structure associated.
78 struct pmac_i2c_bus
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;
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);
101 static LIST_HEAD(pmac_i2c_busses);
104 * Keywest implementation
107 struct pmac_i2c_host_kw
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;
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;
138 /* The Tumbler audio equalizer can be really slow sometimes */
139 #define KW_POLL_TIMEOUT (2*HZ)
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
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
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
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
172 /* State machine states */
173 enum {
174 state_idle,
175 state_addr,
176 state_read,
177 state_write,
178 state_stop,
179 state_dead
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)
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"
197 static inline u8 __kw_read_reg(struct pmac_i2c_host_kw *host, reg_t reg)
199 return readb(host->base + (((unsigned int)reg) << host->bsteps));
202 static inline void __kw_write_reg(struct pmac_i2c_host_kw *host,
203 reg_t reg, u8 val)
205 writeb(val, host->base + (((unsigned)reg) << host->bsteps));
206 (void)__kw_read_reg(host, reg_subaddr);
209 #define kw_write_reg(reg, val) __kw_write_reg(host, reg, val)
210 #define kw_read_reg(reg) __kw_read_reg(host, reg)
212 static u8 kw_i2c_wait_interrupt(struct pmac_i2c_host_kw *host)
214 int i, j;
215 u8 isr;
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;
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....
226 if (host->polled) {
227 for (j = 1; j < 100000; j++)
228 mb();
229 } else
230 msleep(1);
232 return isr;
235 static void kw_i2c_do_stop(struct pmac_i2c_host_kw *host, int result)
237 kw_write_reg(reg_control, KW_I2C_CTL_STOP);
238 host->state = state_stop;
239 host->result = result;
243 static void kw_i2c_handle_interrupt(struct pmac_i2c_host_kw *host, u8 isr)
245 u8 ack;
247 DBG_LOW("kw_handle_interrupt(%s, isr: %x)\n",
248 __kw_state_names[host->state], isr);
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;
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;
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;
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);
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--;
298 kw_write_reg(reg_isr, KW_I2C_IRQ_ADDR);
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);
326 kw_write_reg(reg_isr, KW_I2C_IRQ_DATA);
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;
335 host->state = state_idle;
336 if (!host->polled)
337 complete(&host->complete);
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);
346 /* Interrupt handler */
347 static irqreturn_t kw_i2c_irq(int irq, void *dev_id)
349 struct pmac_i2c_host_kw *host = dev_id;
350 unsigned long flags;
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);
359 spin_unlock_irqrestore(&host->lock, flags);
360 return IRQ_HANDLED;
363 static void kw_i2c_timeout(unsigned long data)
365 struct pmac_i2c_host_kw *host = (struct pmac_i2c_host_kw *)data;
366 unsigned long flags;
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);
374 spin_unlock_irqrestore(&host->lock, flags);
377 static int kw_i2c_open(struct pmac_i2c_bus *bus)
379 struct pmac_i2c_host_kw *host = bus->hostdata;
380 mutex_lock(&host->mutex);
381 return 0;
384 static void kw_i2c_close(struct pmac_i2c_bus *bus)
386 struct pmac_i2c_host_kw *host = bus->hostdata;
387 mutex_unlock(&host->mutex);
390 static int kw_i2c_xfer(struct pmac_i2c_bus *bus, u8 addrdir, int subsize,
391 u32 subaddr, u8 *data, int len)
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;
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;
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);
423 /* Set up address and r/w bit, strip possible stale bus number from
424 * address top bits
426 kw_write_reg(reg_addr, addrdir & 0xff);
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);
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;
441 /* Enable interrupt if not using polled mode and interrupt is
442 * available
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);
456 /* Start sending address */
457 kw_write_reg(reg_control, KW_I2C_CTL_XADDR);
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;
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);
473 /* Disable emission */
474 kw_write_reg(reg_ier, 0);
476 return host->result;
479 static struct pmac_i2c_host_kw *__init kw_i2c_host_init(struct device_node *np)
481 struct pmac_i2c_host_kw *host;
482 const u32 *psteps, *prate, *addrp;
483 u32 steps;
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;
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
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;
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;
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;
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);
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;
542 /* Make sure IRQ is disabled */
543 kw_write_reg(reg_ier, 0);
545 /* Request chip interrupt. We set IRQF_NO_SUSPEND 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
549 if (request_irq(host->irq, kw_i2c_irq, IRQF_NO_SUSPEND,
550 "keywest i2c", host))
551 host->irq = NO_IRQ;
553 printk(KERN_INFO "KeyWest i2c @0x%08x irq %d %s\n",
554 *addrp, host->irq, np->full_name);
556 return host;
560 static void __init kw_i2c_add(struct pmac_i2c_host_kw *host,
561 struct device_node *controller,
562 struct device_node *busnode,
563 int channel)
565 struct pmac_i2c_bus *bus;
567 bus = kzalloc(sizeof(struct pmac_i2c_bus), GFP_KERNEL);
568 if (bus == NULL)
569 return;
571 bus->controller = of_node_get(controller);
572 bus->busnode = of_node_get(busnode);
573 bus->type = pmac_i2c_bus_keywest;
574 bus->hostdata = host;
575 bus->channel = channel;
576 bus->mode = pmac_i2c_mode_std;
577 bus->open = kw_i2c_open;
578 bus->close = kw_i2c_close;
579 bus->xfer = kw_i2c_xfer;
580 mutex_init(&bus->mutex);
581 if (controller == busnode)
582 bus->flags = pmac_i2c_multibus;
583 list_add(&bus->link, &pmac_i2c_busses);
585 printk(KERN_INFO " channel %d bus %s\n", channel,
586 (controller == busnode) ? "<multibus>" : busnode->full_name);
589 static void __init kw_i2c_probe(void)
591 struct device_node *np, *child, *parent;
593 /* Probe keywest-i2c busses */
594 for_each_compatible_node(np, "i2c","keywest-i2c") {
595 struct pmac_i2c_host_kw *host;
596 int multibus;
598 /* Found one, init a host structure */
599 host = kw_i2c_host_init(np);
600 if (host == NULL)
601 continue;
603 /* Now check if we have a multibus setup (old style) or if we
604 * have proper bus nodes. Note that the "new" way (proper bus
605 * nodes) might cause us to not create some busses that are
606 * kept hidden in the device-tree. In the future, we might
607 * want to work around that by creating busses without a node
608 * but not for now
610 child = of_get_next_child(np, NULL);
611 multibus = !child || strcmp(child->name, "i2c-bus");
612 of_node_put(child);
614 /* For a multibus setup, we get the bus count based on the
615 * parent type
617 if (multibus) {
618 int chans, i;
620 parent = of_get_parent(np);
621 if (parent == NULL)
622 continue;
623 chans = parent->name[0] == 'u' ? 2 : 1;
624 for (i = 0; i < chans; i++)
625 kw_i2c_add(host, np, np, i);
626 } else {
627 for (child = NULL;
628 (child = of_get_next_child(np, child)) != NULL;) {
629 const u32 *reg = of_get_property(child,
630 "reg", NULL);
631 if (reg == NULL)
632 continue;
633 kw_i2c_add(host, np, child, *reg);
642 * PMU implementation
646 #ifdef CONFIG_ADB_PMU
649 * i2c command block to the PMU
651 struct pmu_i2c_hdr {
652 u8 bus;
653 u8 mode;
654 u8 bus2;
655 u8 address;
656 u8 sub_addr;
657 u8 comb_addr;
658 u8 count;
659 u8 data[];
662 static void pmu_i2c_complete(struct adb_request *req)
664 complete(req->arg);
667 static int pmu_i2c_xfer(struct pmac_i2c_bus *bus, u8 addrdir, int subsize,
668 u32 subaddr, u8 *data, int len)
670 struct adb_request *req = bus->hostdata;
671 struct pmu_i2c_hdr *hdr = (struct pmu_i2c_hdr *)&req->data[1];
672 struct completion comp;
673 int read = addrdir & 1;
674 int retry;
675 int rc = 0;
677 /* For now, limit ourselves to 16 bytes transfers */
678 if (len > 16)
679 return -EINVAL;
681 init_completion(&comp);
683 for (retry = 0; retry < 16; retry++) {
684 memset(req, 0, sizeof(struct adb_request));
685 hdr->bus = bus->channel;
686 hdr->count = len;
688 switch(bus->mode) {
689 case pmac_i2c_mode_std:
690 if (subsize != 0)
691 return -EINVAL;
692 hdr->address = addrdir;
693 hdr->mode = PMU_I2C_MODE_SIMPLE;
694 break;
695 case pmac_i2c_mode_stdsub:
696 case pmac_i2c_mode_combined:
697 if (subsize != 1)
698 return -EINVAL;
699 hdr->address = addrdir & 0xfe;
700 hdr->comb_addr = addrdir;
701 hdr->sub_addr = subaddr;
702 if (bus->mode == pmac_i2c_mode_stdsub)
703 hdr->mode = PMU_I2C_MODE_STDSUB;
704 else
705 hdr->mode = PMU_I2C_MODE_COMBINED;
706 break;
707 default:
708 return -EINVAL;
711 INIT_COMPLETION(comp);
712 req->data[0] = PMU_I2C_CMD;
713 req->reply[0] = 0xff;
714 req->nbytes = sizeof(struct pmu_i2c_hdr) + 1;
715 req->done = pmu_i2c_complete;
716 req->arg = &comp;
717 if (!read && len) {
718 memcpy(hdr->data, data, len);
719 req->nbytes += len;
721 rc = pmu_queue_request(req);
722 if (rc)
723 return rc;
724 wait_for_completion(&comp);
725 if (req->reply[0] == PMU_I2C_STATUS_OK)
726 break;
727 msleep(15);
729 if (req->reply[0] != PMU_I2C_STATUS_OK)
730 return -EIO;
732 for (retry = 0; retry < 16; retry++) {
733 memset(req, 0, sizeof(struct adb_request));
735 /* I know that looks like a lot, slow as hell, but darwin
736 * does it so let's be on the safe side for now
738 msleep(15);
740 hdr->bus = PMU_I2C_BUS_STATUS;
742 INIT_COMPLETION(comp);
743 req->data[0] = PMU_I2C_CMD;
744 req->reply[0] = 0xff;
745 req->nbytes = 2;
746 req->done = pmu_i2c_complete;
747 req->arg = &comp;
748 rc = pmu_queue_request(req);
749 if (rc)
750 return rc;
751 wait_for_completion(&comp);
753 if (req->reply[0] == PMU_I2C_STATUS_OK && !read)
754 return 0;
755 if (req->reply[0] == PMU_I2C_STATUS_DATAREAD && read) {
756 int rlen = req->reply_len - 1;
758 if (rlen != len) {
759 printk(KERN_WARNING "low_i2c: PMU returned %d"
760 " bytes, expected %d !\n", rlen, len);
761 return -EIO;
763 if (len)
764 memcpy(data, &req->reply[1], len);
765 return 0;
768 return -EIO;
771 static void __init pmu_i2c_probe(void)
773 struct pmac_i2c_bus *bus;
774 struct device_node *busnode;
775 int channel, sz;
777 if (!pmu_present())
778 return;
780 /* There might or might not be a "pmu-i2c" node, we use that
781 * or via-pmu itself, whatever we find. I haven't seen a machine
782 * with separate bus nodes, so we assume a multibus setup
784 busnode = of_find_node_by_name(NULL, "pmu-i2c");
785 if (busnode == NULL)
786 busnode = of_find_node_by_name(NULL, "via-pmu");
787 if (busnode == NULL)
788 return;
790 printk(KERN_INFO "PMU i2c %s\n", busnode->full_name);
793 * We add bus 1 and 2 only for now, bus 0 is "special"
795 for (channel = 1; channel <= 2; channel++) {
796 sz = sizeof(struct pmac_i2c_bus) + sizeof(struct adb_request);
797 bus = kzalloc(sz, GFP_KERNEL);
798 if (bus == NULL)
799 return;
801 bus->controller = busnode;
802 bus->busnode = busnode;
803 bus->type = pmac_i2c_bus_pmu;
804 bus->channel = channel;
805 bus->mode = pmac_i2c_mode_std;
806 bus->hostdata = bus + 1;
807 bus->xfer = pmu_i2c_xfer;
808 mutex_init(&bus->mutex);
809 bus->flags = pmac_i2c_multibus;
810 list_add(&bus->link, &pmac_i2c_busses);
812 printk(KERN_INFO " channel %d bus <multibus>\n", channel);
816 #endif /* CONFIG_ADB_PMU */
821 * SMU implementation
825 #ifdef CONFIG_PMAC_SMU
827 static void smu_i2c_complete(struct smu_i2c_cmd *cmd, void *misc)
829 complete(misc);
832 static int smu_i2c_xfer(struct pmac_i2c_bus *bus, u8 addrdir, int subsize,
833 u32 subaddr, u8 *data, int len)
835 struct smu_i2c_cmd *cmd = bus->hostdata;
836 struct completion comp;
837 int read = addrdir & 1;
838 int rc = 0;
840 if ((read && len > SMU_I2C_READ_MAX) ||
841 ((!read) && len > SMU_I2C_WRITE_MAX))
842 return -EINVAL;
844 memset(cmd, 0, sizeof(struct smu_i2c_cmd));
845 cmd->info.bus = bus->channel;
846 cmd->info.devaddr = addrdir;
847 cmd->info.datalen = len;
849 switch(bus->mode) {
850 case pmac_i2c_mode_std:
851 if (subsize != 0)
852 return -EINVAL;
853 cmd->info.type = SMU_I2C_TRANSFER_SIMPLE;
854 break;
855 case pmac_i2c_mode_stdsub:
856 case pmac_i2c_mode_combined:
857 if (subsize > 3 || subsize < 1)
858 return -EINVAL;
859 cmd->info.sublen = subsize;
860 /* that's big-endian only but heh ! */
861 memcpy(&cmd->info.subaddr, ((char *)&subaddr) + (4 - subsize),
862 subsize);
863 if (bus->mode == pmac_i2c_mode_stdsub)
864 cmd->info.type = SMU_I2C_TRANSFER_STDSUB;
865 else
866 cmd->info.type = SMU_I2C_TRANSFER_COMBINED;
867 break;
868 default:
869 return -EINVAL;
871 if (!read && len)
872 memcpy(cmd->info.data, data, len);
874 init_completion(&comp);
875 cmd->done = smu_i2c_complete;
876 cmd->misc = &comp;
877 rc = smu_queue_i2c(cmd);
878 if (rc < 0)
879 return rc;
880 wait_for_completion(&comp);
881 rc = cmd->status;
883 if (read && len)
884 memcpy(data, cmd->info.data, len);
885 return rc < 0 ? rc : 0;
888 static void __init smu_i2c_probe(void)
890 struct device_node *controller, *busnode;
891 struct pmac_i2c_bus *bus;
892 const u32 *reg;
893 int sz;
895 if (!smu_present())
896 return;
898 controller = of_find_node_by_name(NULL, "smu-i2c-control");
899 if (controller == NULL)
900 controller = of_find_node_by_name(NULL, "smu");
901 if (controller == NULL)
902 return;
904 printk(KERN_INFO "SMU i2c %s\n", controller->full_name);
906 /* Look for childs, note that they might not be of the right
907 * type as older device trees mix i2c busses and other things
908 * at the same level
910 for (busnode = NULL;
911 (busnode = of_get_next_child(controller, busnode)) != NULL;) {
912 if (strcmp(busnode->type, "i2c") &&
913 strcmp(busnode->type, "i2c-bus"))
914 continue;
915 reg = of_get_property(busnode, "reg", NULL);
916 if (reg == NULL)
917 continue;
919 sz = sizeof(struct pmac_i2c_bus) + sizeof(struct smu_i2c_cmd);
920 bus = kzalloc(sz, GFP_KERNEL);
921 if (bus == NULL)
922 return;
924 bus->controller = controller;
925 bus->busnode = of_node_get(busnode);
926 bus->type = pmac_i2c_bus_smu;
927 bus->channel = *reg;
928 bus->mode = pmac_i2c_mode_std;
929 bus->hostdata = bus + 1;
930 bus->xfer = smu_i2c_xfer;
931 mutex_init(&bus->mutex);
932 bus->flags = 0;
933 list_add(&bus->link, &pmac_i2c_busses);
935 printk(KERN_INFO " channel %x bus %s\n",
936 bus->channel, busnode->full_name);
940 #endif /* CONFIG_PMAC_SMU */
944 * Core code
949 struct pmac_i2c_bus *pmac_i2c_find_bus(struct device_node *node)
951 struct device_node *p = of_node_get(node);
952 struct device_node *prev = NULL;
953 struct pmac_i2c_bus *bus;
955 while(p) {
956 list_for_each_entry(bus, &pmac_i2c_busses, link) {
957 if (p == bus->busnode) {
958 if (prev && bus->flags & pmac_i2c_multibus) {
959 const u32 *reg;
960 reg = of_get_property(prev, "reg",
961 NULL);
962 if (!reg)
963 continue;
964 if (((*reg) >> 8) != bus->channel)
965 continue;
967 of_node_put(p);
968 of_node_put(prev);
969 return bus;
972 of_node_put(prev);
973 prev = p;
974 p = of_get_parent(p);
976 return NULL;
978 EXPORT_SYMBOL_GPL(pmac_i2c_find_bus);
980 u8 pmac_i2c_get_dev_addr(struct device_node *device)
982 const u32 *reg = of_get_property(device, "reg", NULL);
984 if (reg == NULL)
985 return 0;
987 return (*reg) & 0xff;
989 EXPORT_SYMBOL_GPL(pmac_i2c_get_dev_addr);
991 struct device_node *pmac_i2c_get_controller(struct pmac_i2c_bus *bus)
993 return bus->controller;
995 EXPORT_SYMBOL_GPL(pmac_i2c_get_controller);
997 struct device_node *pmac_i2c_get_bus_node(struct pmac_i2c_bus *bus)
999 return bus->busnode;
1001 EXPORT_SYMBOL_GPL(pmac_i2c_get_bus_node);
1003 int pmac_i2c_get_type(struct pmac_i2c_bus *bus)
1005 return bus->type;
1007 EXPORT_SYMBOL_GPL(pmac_i2c_get_type);
1009 int pmac_i2c_get_flags(struct pmac_i2c_bus *bus)
1011 return bus->flags;
1013 EXPORT_SYMBOL_GPL(pmac_i2c_get_flags);
1015 int pmac_i2c_get_channel(struct pmac_i2c_bus *bus)
1017 return bus->channel;
1019 EXPORT_SYMBOL_GPL(pmac_i2c_get_channel);
1022 struct i2c_adapter *pmac_i2c_get_adapter(struct pmac_i2c_bus *bus)
1024 return &bus->adapter;
1026 EXPORT_SYMBOL_GPL(pmac_i2c_get_adapter);
1028 struct pmac_i2c_bus *pmac_i2c_adapter_to_bus(struct i2c_adapter *adapter)
1030 struct pmac_i2c_bus *bus;
1032 list_for_each_entry(bus, &pmac_i2c_busses, link)
1033 if (&bus->adapter == adapter)
1034 return bus;
1035 return NULL;
1037 EXPORT_SYMBOL_GPL(pmac_i2c_adapter_to_bus);
1039 int pmac_i2c_match_adapter(struct device_node *dev, struct i2c_adapter *adapter)
1041 struct pmac_i2c_bus *bus = pmac_i2c_find_bus(dev);
1043 if (bus == NULL)
1044 return 0;
1045 return (&bus->adapter == adapter);
1047 EXPORT_SYMBOL_GPL(pmac_i2c_match_adapter);
1049 int pmac_low_i2c_lock(struct device_node *np)
1051 struct pmac_i2c_bus *bus, *found = NULL;
1053 list_for_each_entry(bus, &pmac_i2c_busses, link) {
1054 if (np == bus->controller) {
1055 found = bus;
1056 break;
1059 if (!found)
1060 return -ENODEV;
1061 return pmac_i2c_open(bus, 0);
1063 EXPORT_SYMBOL_GPL(pmac_low_i2c_lock);
1065 int pmac_low_i2c_unlock(struct device_node *np)
1067 struct pmac_i2c_bus *bus, *found = NULL;
1069 list_for_each_entry(bus, &pmac_i2c_busses, link) {
1070 if (np == bus->controller) {
1071 found = bus;
1072 break;
1075 if (!found)
1076 return -ENODEV;
1077 pmac_i2c_close(bus);
1078 return 0;
1080 EXPORT_SYMBOL_GPL(pmac_low_i2c_unlock);
1083 int pmac_i2c_open(struct pmac_i2c_bus *bus, int polled)
1085 int rc;
1087 mutex_lock(&bus->mutex);
1088 bus->polled = polled || pmac_i2c_force_poll;
1089 bus->opened = 1;
1090 bus->mode = pmac_i2c_mode_std;
1091 if (bus->open && (rc = bus->open(bus)) != 0) {
1092 bus->opened = 0;
1093 mutex_unlock(&bus->mutex);
1094 return rc;
1096 return 0;
1098 EXPORT_SYMBOL_GPL(pmac_i2c_open);
1100 void pmac_i2c_close(struct pmac_i2c_bus *bus)
1102 WARN_ON(!bus->opened);
1103 if (bus->close)
1104 bus->close(bus);
1105 bus->opened = 0;
1106 mutex_unlock(&bus->mutex);
1108 EXPORT_SYMBOL_GPL(pmac_i2c_close);
1110 int pmac_i2c_setmode(struct pmac_i2c_bus *bus, int mode)
1112 WARN_ON(!bus->opened);
1114 /* Report me if you see the error below as there might be a new
1115 * "combined4" mode that I need to implement for the SMU bus
1117 if (mode < pmac_i2c_mode_dumb || mode > pmac_i2c_mode_combined) {
1118 printk(KERN_ERR "low_i2c: Invalid mode %d requested on"
1119 " bus %s !\n", mode, bus->busnode->full_name);
1120 return -EINVAL;
1122 bus->mode = mode;
1124 return 0;
1126 EXPORT_SYMBOL_GPL(pmac_i2c_setmode);
1128 int pmac_i2c_xfer(struct pmac_i2c_bus *bus, u8 addrdir, int subsize,
1129 u32 subaddr, u8 *data, int len)
1131 int rc;
1133 WARN_ON(!bus->opened);
1135 DBG("xfer() chan=%d, addrdir=0x%x, mode=%d, subsize=%d, subaddr=0x%x,"
1136 " %d bytes, bus %s\n", bus->channel, addrdir, bus->mode, subsize,
1137 subaddr, len, bus->busnode->full_name);
1139 rc = bus->xfer(bus, addrdir, subsize, subaddr, data, len);
1141 #ifdef DEBUG
1142 if (rc)
1143 DBG("xfer error %d\n", rc);
1144 #endif
1145 return rc;
1147 EXPORT_SYMBOL_GPL(pmac_i2c_xfer);
1149 /* some quirks for platform function decoding */
1150 enum {
1151 pmac_i2c_quirk_invmask = 0x00000001u,
1152 pmac_i2c_quirk_skip = 0x00000002u,
1155 static void pmac_i2c_devscan(void (*callback)(struct device_node *dev,
1156 int quirks))
1158 struct pmac_i2c_bus *bus;
1159 struct device_node *np;
1160 static struct whitelist_ent {
1161 char *name;
1162 char *compatible;
1163 int quirks;
1164 } whitelist[] = {
1165 /* XXX Study device-tree's & apple drivers are get the quirks
1166 * right !
1168 /* Workaround: It seems that running the clockspreading
1169 * properties on the eMac will cause lockups during boot.
1170 * The machine seems to work fine without that. So for now,
1171 * let's make sure i2c-hwclock doesn't match about "imic"
1172 * clocks and we'll figure out if we really need to do
1173 * something special about those later.
1175 { "i2c-hwclock", "imic5002", pmac_i2c_quirk_skip },
1176 { "i2c-hwclock", "imic5003", pmac_i2c_quirk_skip },
1177 { "i2c-hwclock", NULL, pmac_i2c_quirk_invmask },
1178 { "i2c-cpu-voltage", NULL, 0},
1179 { "temp-monitor", NULL, 0 },
1180 { "supply-monitor", NULL, 0 },
1181 { NULL, NULL, 0 },
1184 /* Only some devices need to have platform functions instanciated
1185 * here. For now, we have a table. Others, like 9554 i2c GPIOs used
1186 * on Xserve, if we ever do a driver for them, will use their own
1187 * platform function instance
1189 list_for_each_entry(bus, &pmac_i2c_busses, link) {
1190 for (np = NULL;
1191 (np = of_get_next_child(bus->busnode, np)) != NULL;) {
1192 struct whitelist_ent *p;
1193 /* If multibus, check if device is on that bus */
1194 if (bus->flags & pmac_i2c_multibus)
1195 if (bus != pmac_i2c_find_bus(np))
1196 continue;
1197 for (p = whitelist; p->name != NULL; p++) {
1198 if (strcmp(np->name, p->name))
1199 continue;
1200 if (p->compatible &&
1201 !of_device_is_compatible(np, p->compatible))
1202 continue;
1203 if (p->quirks & pmac_i2c_quirk_skip)
1204 break;
1205 callback(np, p->quirks);
1206 break;
1212 #define MAX_I2C_DATA 64
1214 struct pmac_i2c_pf_inst
1216 struct pmac_i2c_bus *bus;
1217 u8 addr;
1218 u8 buffer[MAX_I2C_DATA];
1219 u8 scratch[MAX_I2C_DATA];
1220 int bytes;
1221 int quirks;
1224 static void* pmac_i2c_do_begin(struct pmf_function *func, struct pmf_args *args)
1226 struct pmac_i2c_pf_inst *inst;
1227 struct pmac_i2c_bus *bus;
1229 bus = pmac_i2c_find_bus(func->node);
1230 if (bus == NULL) {
1231 printk(KERN_ERR "low_i2c: Can't find bus for %s (pfunc)\n",
1232 func->node->full_name);
1233 return NULL;
1235 if (pmac_i2c_open(bus, 0)) {
1236 printk(KERN_ERR "low_i2c: Can't open i2c bus for %s (pfunc)\n",
1237 func->node->full_name);
1238 return NULL;
1241 /* XXX might need GFP_ATOMIC when called during the suspend process,
1242 * but then, there are already lots of issues with suspending when
1243 * near OOM that need to be resolved, the allocator itself should
1244 * probably make GFP_NOIO implicit during suspend
1246 inst = kzalloc(sizeof(struct pmac_i2c_pf_inst), GFP_KERNEL);
1247 if (inst == NULL) {
1248 pmac_i2c_close(bus);
1249 return NULL;
1251 inst->bus = bus;
1252 inst->addr = pmac_i2c_get_dev_addr(func->node);
1253 inst->quirks = (int)(long)func->driver_data;
1254 return inst;
1257 static void pmac_i2c_do_end(struct pmf_function *func, void *instdata)
1259 struct pmac_i2c_pf_inst *inst = instdata;
1261 if (inst == NULL)
1262 return;
1263 pmac_i2c_close(inst->bus);
1264 kfree(inst);
1267 static int pmac_i2c_do_read(PMF_STD_ARGS, u32 len)
1269 struct pmac_i2c_pf_inst *inst = instdata;
1271 inst->bytes = len;
1272 return pmac_i2c_xfer(inst->bus, inst->addr | pmac_i2c_read, 0, 0,
1273 inst->buffer, len);
1276 static int pmac_i2c_do_write(PMF_STD_ARGS, u32 len, const u8 *data)
1278 struct pmac_i2c_pf_inst *inst = instdata;
1280 return pmac_i2c_xfer(inst->bus, inst->addr | pmac_i2c_write, 0, 0,
1281 (u8 *)data, len);
1284 /* This function is used to do the masking & OR'ing for the "rmw" type
1285 * callbacks. Ze should apply the mask and OR in the values in the
1286 * buffer before writing back. The problem is that it seems that
1287 * various darwin drivers implement the mask/or differently, thus
1288 * we need to check the quirks first
1290 static void pmac_i2c_do_apply_rmw(struct pmac_i2c_pf_inst *inst,
1291 u32 len, const u8 *mask, const u8 *val)
1293 int i;
1295 if (inst->quirks & pmac_i2c_quirk_invmask) {
1296 for (i = 0; i < len; i ++)
1297 inst->scratch[i] = (inst->buffer[i] & mask[i]) | val[i];
1298 } else {
1299 for (i = 0; i < len; i ++)
1300 inst->scratch[i] = (inst->buffer[i] & ~mask[i])
1301 | (val[i] & mask[i]);
1305 static int pmac_i2c_do_rmw(PMF_STD_ARGS, u32 masklen, u32 valuelen,
1306 u32 totallen, const u8 *maskdata,
1307 const u8 *valuedata)
1309 struct pmac_i2c_pf_inst *inst = instdata;
1311 if (masklen > inst->bytes || valuelen > inst->bytes ||
1312 totallen > inst->bytes || valuelen > masklen)
1313 return -EINVAL;
1315 pmac_i2c_do_apply_rmw(inst, masklen, maskdata, valuedata);
1317 return pmac_i2c_xfer(inst->bus, inst->addr | pmac_i2c_write, 0, 0,
1318 inst->scratch, totallen);
1321 static int pmac_i2c_do_read_sub(PMF_STD_ARGS, u8 subaddr, u32 len)
1323 struct pmac_i2c_pf_inst *inst = instdata;
1325 inst->bytes = len;
1326 return pmac_i2c_xfer(inst->bus, inst->addr | pmac_i2c_read, 1, subaddr,
1327 inst->buffer, len);
1330 static int pmac_i2c_do_write_sub(PMF_STD_ARGS, u8 subaddr, u32 len,
1331 const u8 *data)
1333 struct pmac_i2c_pf_inst *inst = instdata;
1335 return pmac_i2c_xfer(inst->bus, inst->addr | pmac_i2c_write, 1,
1336 subaddr, (u8 *)data, len);
1339 static int pmac_i2c_do_set_mode(PMF_STD_ARGS, int mode)
1341 struct pmac_i2c_pf_inst *inst = instdata;
1343 return pmac_i2c_setmode(inst->bus, mode);
1346 static int pmac_i2c_do_rmw_sub(PMF_STD_ARGS, u8 subaddr, u32 masklen,
1347 u32 valuelen, u32 totallen, const u8 *maskdata,
1348 const u8 *valuedata)
1350 struct pmac_i2c_pf_inst *inst = instdata;
1352 if (masklen > inst->bytes || valuelen > inst->bytes ||
1353 totallen > inst->bytes || valuelen > masklen)
1354 return -EINVAL;
1356 pmac_i2c_do_apply_rmw(inst, masklen, maskdata, valuedata);
1358 return pmac_i2c_xfer(inst->bus, inst->addr | pmac_i2c_write, 1,
1359 subaddr, inst->scratch, totallen);
1362 static int pmac_i2c_do_mask_and_comp(PMF_STD_ARGS, u32 len,
1363 const u8 *maskdata,
1364 const u8 *valuedata)
1366 struct pmac_i2c_pf_inst *inst = instdata;
1367 int i, match;
1369 /* Get return value pointer, it's assumed to be a u32 */
1370 if (!args || !args->count || !args->u[0].p)
1371 return -EINVAL;
1373 /* Check buffer */
1374 if (len > inst->bytes)
1375 return -EINVAL;
1377 for (i = 0, match = 1; match && i < len; i ++)
1378 if ((inst->buffer[i] & maskdata[i]) != valuedata[i])
1379 match = 0;
1380 *args->u[0].p = match;
1381 return 0;
1384 static int pmac_i2c_do_delay(PMF_STD_ARGS, u32 duration)
1386 msleep((duration + 999) / 1000);
1387 return 0;
1391 static struct pmf_handlers pmac_i2c_pfunc_handlers = {
1392 .begin = pmac_i2c_do_begin,
1393 .end = pmac_i2c_do_end,
1394 .read_i2c = pmac_i2c_do_read,
1395 .write_i2c = pmac_i2c_do_write,
1396 .rmw_i2c = pmac_i2c_do_rmw,
1397 .read_i2c_sub = pmac_i2c_do_read_sub,
1398 .write_i2c_sub = pmac_i2c_do_write_sub,
1399 .rmw_i2c_sub = pmac_i2c_do_rmw_sub,
1400 .set_i2c_mode = pmac_i2c_do_set_mode,
1401 .mask_and_compare = pmac_i2c_do_mask_and_comp,
1402 .delay = pmac_i2c_do_delay,
1405 static void __init pmac_i2c_dev_create(struct device_node *np, int quirks)
1407 DBG("dev_create(%s)\n", np->full_name);
1409 pmf_register_driver(np, &pmac_i2c_pfunc_handlers,
1410 (void *)(long)quirks);
1413 static void __init pmac_i2c_dev_init(struct device_node *np, int quirks)
1415 DBG("dev_create(%s)\n", np->full_name);
1417 pmf_do_functions(np, NULL, 0, PMF_FLAGS_ON_INIT, NULL);
1420 static void pmac_i2c_dev_suspend(struct device_node *np, int quirks)
1422 DBG("dev_suspend(%s)\n", np->full_name);
1423 pmf_do_functions(np, NULL, 0, PMF_FLAGS_ON_SLEEP, NULL);
1426 static void pmac_i2c_dev_resume(struct device_node *np, int quirks)
1428 DBG("dev_resume(%s)\n", np->full_name);
1429 pmf_do_functions(np, NULL, 0, PMF_FLAGS_ON_WAKE, NULL);
1432 void pmac_pfunc_i2c_suspend(void)
1434 pmac_i2c_devscan(pmac_i2c_dev_suspend);
1437 void pmac_pfunc_i2c_resume(void)
1439 pmac_i2c_devscan(pmac_i2c_dev_resume);
1443 * Initialize us: probe all i2c busses on the machine, instantiate
1444 * busses and platform functions as needed.
1446 /* This is non-static as it might be called early by smp code */
1447 int __init pmac_i2c_init(void)
1449 static int i2c_inited;
1451 if (i2c_inited)
1452 return 0;
1453 i2c_inited = 1;
1455 /* Probe keywest-i2c busses */
1456 kw_i2c_probe();
1458 #ifdef CONFIG_ADB_PMU
1459 /* Probe PMU i2c busses */
1460 pmu_i2c_probe();
1461 #endif
1463 #ifdef CONFIG_PMAC_SMU
1464 /* Probe SMU i2c busses */
1465 smu_i2c_probe();
1466 #endif
1468 /* Now add plaform functions for some known devices */
1469 pmac_i2c_devscan(pmac_i2c_dev_create);
1471 return 0;
1473 machine_arch_initcall(powermac, pmac_i2c_init);
1475 /* Since pmac_i2c_init can be called too early for the platform device
1476 * registration, we need to do it at a later time. In our case, subsys
1477 * happens to fit well, though I agree it's a bit of a hack...
1479 static int __init pmac_i2c_create_platform_devices(void)
1481 struct pmac_i2c_bus *bus;
1482 int i = 0;
1484 /* In the case where we are initialized from smp_init(), we must
1485 * not use the timer (and thus the irq). It's safe from now on
1486 * though
1488 pmac_i2c_force_poll = 0;
1490 /* Create platform devices */
1491 list_for_each_entry(bus, &pmac_i2c_busses, link) {
1492 bus->platform_dev =
1493 platform_device_alloc("i2c-powermac", i++);
1494 if (bus->platform_dev == NULL)
1495 return -ENOMEM;
1496 bus->platform_dev->dev.platform_data = bus;
1497 platform_device_add(bus->platform_dev);
1500 /* Now call platform "init" functions */
1501 pmac_i2c_devscan(pmac_i2c_dev_init);
1503 return 0;
1505 machine_subsys_initcall(powermac, pmac_i2c_create_platform_devices);