[PATCH] 3/5 powerpc: Add platform functions interpreter
[linux-2.6.22.y-op.git] / arch / powerpc / platforms / powermac / low_i2c.c
blob535c802b369fbe945dd8de334e86a910aaffb1f4
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/config.h>
34 #include <linux/types.h>
35 #include <linux/sched.h>
36 #include <linux/init.h>
37 #include <linux/module.h>
38 #include <linux/adb.h>
39 #include <linux/pmu.h>
40 #include <linux/delay.h>
41 #include <linux/completion.h>
42 #include <linux/platform_device.h>
43 #include <linux/interrupt.h>
44 #include <linux/completion.h>
45 #include <linux/timer.h>
46 #include <asm/keylargo.h>
47 #include <asm/uninorth.h>
48 #include <asm/io.h>
49 #include <asm/prom.h>
50 #include <asm/machdep.h>
51 #include <asm/smu.h>
52 #include <asm/pmac_pfunc.h>
53 #include <asm/pmac_low_i2c.h>
55 #ifdef DEBUG
56 #define DBG(x...) do {\
57 printk(KERN_DEBUG "low_i2c:" x); \
58 } while(0)
59 #else
60 #define DBG(x...)
61 #endif
63 #ifdef DEBUG_LOW
64 #define DBG_LOW(x...) do {\
65 printk(KERN_DEBUG "low_i2c:" x); \
66 } while(0)
67 #else
68 #define DBG_LOW(x...)
69 #endif
72 static int pmac_i2c_force_poll = 1;
75 * A bus structure. Each bus in the system has such a structure associated.
77 struct pmac_i2c_bus
79 struct list_head link;
80 struct device_node *controller;
81 struct device_node *busnode;
82 int type;
83 int flags;
84 struct i2c_adapter *adapter;
85 void *hostdata;
86 int channel; /* some hosts have multiple */
87 int mode; /* current mode */
88 struct semaphore sem;
89 int opened;
90 int polled; /* open mode */
91 struct platform_device *platform_dev;
93 /* ops */
94 int (*open)(struct pmac_i2c_bus *bus);
95 void (*close)(struct pmac_i2c_bus *bus);
96 int (*xfer)(struct pmac_i2c_bus *bus, u8 addrdir, int subsize,
97 u32 subaddr, u8 *data, int len);
100 static LIST_HEAD(pmac_i2c_busses);
103 * Keywest implementation
106 struct pmac_i2c_host_kw
108 struct semaphore mutex; /* Access mutex for use by
109 * i2c-keywest */
110 void __iomem *base; /* register base address */
111 int bsteps; /* register stepping */
112 int speed; /* speed */
113 int irq;
114 u8 *data;
115 unsigned len;
116 int state;
117 int rw;
118 int polled;
119 int result;
120 struct completion complete;
121 spinlock_t lock;
122 struct timer_list timeout_timer;
125 /* Register indices */
126 typedef enum {
127 reg_mode = 0,
128 reg_control,
129 reg_status,
130 reg_isr,
131 reg_ier,
132 reg_addr,
133 reg_subaddr,
134 reg_data
135 } reg_t;
137 /* The Tumbler audio equalizer can be really slow sometimes */
138 #define KW_POLL_TIMEOUT (2*HZ)
140 /* Mode register */
141 #define KW_I2C_MODE_100KHZ 0x00
142 #define KW_I2C_MODE_50KHZ 0x01
143 #define KW_I2C_MODE_25KHZ 0x02
144 #define KW_I2C_MODE_DUMB 0x00
145 #define KW_I2C_MODE_STANDARD 0x04
146 #define KW_I2C_MODE_STANDARDSUB 0x08
147 #define KW_I2C_MODE_COMBINED 0x0C
148 #define KW_I2C_MODE_MODE_MASK 0x0C
149 #define KW_I2C_MODE_CHAN_MASK 0xF0
151 /* Control register */
152 #define KW_I2C_CTL_AAK 0x01
153 #define KW_I2C_CTL_XADDR 0x02
154 #define KW_I2C_CTL_STOP 0x04
155 #define KW_I2C_CTL_START 0x08
157 /* Status register */
158 #define KW_I2C_STAT_BUSY 0x01
159 #define KW_I2C_STAT_LAST_AAK 0x02
160 #define KW_I2C_STAT_LAST_RW 0x04
161 #define KW_I2C_STAT_SDA 0x08
162 #define KW_I2C_STAT_SCL 0x10
164 /* IER & ISR registers */
165 #define KW_I2C_IRQ_DATA 0x01
166 #define KW_I2C_IRQ_ADDR 0x02
167 #define KW_I2C_IRQ_STOP 0x04
168 #define KW_I2C_IRQ_START 0x08
169 #define KW_I2C_IRQ_MASK 0x0F
171 /* State machine states */
172 enum {
173 state_idle,
174 state_addr,
175 state_read,
176 state_write,
177 state_stop,
178 state_dead
181 #define WRONG_STATE(name) do {\
182 printk(KERN_DEBUG "KW: wrong state. Got %s, state: %s " \
183 "(isr: %02x)\n", \
184 name, __kw_state_names[host->state], isr); \
185 } while(0)
187 static const char *__kw_state_names[] = {
188 "state_idle",
189 "state_addr",
190 "state_read",
191 "state_write",
192 "state_stop",
193 "state_dead"
196 static inline u8 __kw_read_reg(struct pmac_i2c_host_kw *host, reg_t reg)
198 return readb(host->base + (((unsigned int)reg) << host->bsteps));
201 static inline void __kw_write_reg(struct pmac_i2c_host_kw *host,
202 reg_t reg, u8 val)
204 writeb(val, host->base + (((unsigned)reg) << host->bsteps));
205 (void)__kw_read_reg(host, reg_subaddr);
208 #define kw_write_reg(reg, val) __kw_write_reg(host, reg, val)
209 #define kw_read_reg(reg) __kw_read_reg(host, reg)
211 static u8 kw_i2c_wait_interrupt(struct pmac_i2c_host_kw *host)
213 int i, j;
214 u8 isr;
216 for (i = 0; i < 1000; i++) {
217 isr = kw_read_reg(reg_isr) & KW_I2C_IRQ_MASK;
218 if (isr != 0)
219 return isr;
221 /* This code is used with the timebase frozen, we cannot rely
222 * on udelay nor schedule when in polled mode !
223 * For now, just use a bogus loop....
225 if (host->polled) {
226 for (j = 1; j < 100000; j++)
227 mb();
228 } else
229 msleep(1);
231 return isr;
234 static void kw_i2c_handle_interrupt(struct pmac_i2c_host_kw *host, u8 isr)
236 u8 ack;
238 DBG_LOW("kw_handle_interrupt(%s, isr: %x)\n",
239 __kw_state_names[host->state], isr);
241 if (host->state == state_idle) {
242 printk(KERN_WARNING "low_i2c: Keywest got an out of state"
243 " interrupt, ignoring\n");
244 kw_write_reg(reg_isr, isr);
245 return;
248 if (isr == 0) {
249 if (host->state != state_stop) {
250 DBG_LOW("KW: Timeout !\n");
251 host->result = -EIO;
252 goto stop;
254 if (host->state == state_stop) {
255 ack = kw_read_reg(reg_status);
256 if (ack & KW_I2C_STAT_BUSY)
257 kw_write_reg(reg_status, 0);
258 host->state = state_idle;
259 kw_write_reg(reg_ier, 0x00);
260 if (!host->polled)
261 complete(&host->complete);
263 return;
266 if (isr & KW_I2C_IRQ_ADDR) {
267 ack = kw_read_reg(reg_status);
268 if (host->state != state_addr) {
269 kw_write_reg(reg_isr, KW_I2C_IRQ_ADDR);
270 WRONG_STATE("KW_I2C_IRQ_ADDR");
271 host->result = -EIO;
272 goto stop;
274 if ((ack & KW_I2C_STAT_LAST_AAK) == 0) {
275 host->result = -ENODEV;
276 DBG_LOW("KW: NAK on address\n");
277 host->state = state_stop;
278 return;
279 } else {
280 if (host->len == 0) {
281 kw_write_reg(reg_isr, KW_I2C_IRQ_ADDR);
282 goto stop;
284 if (host->rw) {
285 host->state = state_read;
286 if (host->len > 1)
287 kw_write_reg(reg_control,
288 KW_I2C_CTL_AAK);
289 } else {
290 host->state = state_write;
291 kw_write_reg(reg_data, *(host->data++));
292 host->len--;
295 kw_write_reg(reg_isr, KW_I2C_IRQ_ADDR);
298 if (isr & KW_I2C_IRQ_DATA) {
299 if (host->state == state_read) {
300 *(host->data++) = kw_read_reg(reg_data);
301 host->len--;
302 kw_write_reg(reg_isr, KW_I2C_IRQ_DATA);
303 if (host->len == 0)
304 host->state = state_stop;
305 else if (host->len == 1)
306 kw_write_reg(reg_control, 0);
307 } else if (host->state == state_write) {
308 ack = kw_read_reg(reg_status);
309 if ((ack & KW_I2C_STAT_LAST_AAK) == 0) {
310 DBG_LOW("KW: nack on data write\n");
311 host->result = -EIO;
312 goto stop;
313 } else if (host->len) {
314 kw_write_reg(reg_data, *(host->data++));
315 host->len--;
316 } else {
317 kw_write_reg(reg_control, KW_I2C_CTL_STOP);
318 host->state = state_stop;
319 host->result = 0;
321 kw_write_reg(reg_isr, KW_I2C_IRQ_DATA);
322 } else {
323 kw_write_reg(reg_isr, KW_I2C_IRQ_DATA);
324 WRONG_STATE("KW_I2C_IRQ_DATA");
325 if (host->state != state_stop) {
326 host->result = -EIO;
327 goto stop;
332 if (isr & KW_I2C_IRQ_STOP) {
333 kw_write_reg(reg_isr, KW_I2C_IRQ_STOP);
334 if (host->state != state_stop) {
335 WRONG_STATE("KW_I2C_IRQ_STOP");
336 host->result = -EIO;
338 host->state = state_idle;
339 if (!host->polled)
340 complete(&host->complete);
343 if (isr & KW_I2C_IRQ_START)
344 kw_write_reg(reg_isr, KW_I2C_IRQ_START);
346 return;
347 stop:
348 kw_write_reg(reg_control, KW_I2C_CTL_STOP);
349 host->state = state_stop;
350 return;
353 /* Interrupt handler */
354 static irqreturn_t kw_i2c_irq(int irq, void *dev_id, struct pt_regs *regs)
356 struct pmac_i2c_host_kw *host = dev_id;
357 unsigned long flags;
359 spin_lock_irqsave(&host->lock, flags);
360 del_timer(&host->timeout_timer);
361 kw_i2c_handle_interrupt(host, kw_read_reg(reg_isr));
362 if (host->state != state_idle) {
363 host->timeout_timer.expires = jiffies + KW_POLL_TIMEOUT;
364 add_timer(&host->timeout_timer);
366 spin_unlock_irqrestore(&host->lock, flags);
367 return IRQ_HANDLED;
370 static void kw_i2c_timeout(unsigned long data)
372 struct pmac_i2c_host_kw *host = (struct pmac_i2c_host_kw *)data;
373 unsigned long flags;
375 spin_lock_irqsave(&host->lock, flags);
376 kw_i2c_handle_interrupt(host, kw_read_reg(reg_isr));
377 if (host->state != state_idle) {
378 host->timeout_timer.expires = jiffies + KW_POLL_TIMEOUT;
379 add_timer(&host->timeout_timer);
381 spin_unlock_irqrestore(&host->lock, flags);
384 static int kw_i2c_open(struct pmac_i2c_bus *bus)
386 struct pmac_i2c_host_kw *host = bus->hostdata;
387 down(&host->mutex);
388 return 0;
391 static void kw_i2c_close(struct pmac_i2c_bus *bus)
393 struct pmac_i2c_host_kw *host = bus->hostdata;
394 up(&host->mutex);
397 static int kw_i2c_xfer(struct pmac_i2c_bus *bus, u8 addrdir, int subsize,
398 u32 subaddr, u8 *data, int len)
400 struct pmac_i2c_host_kw *host = bus->hostdata;
401 u8 mode_reg = host->speed;
402 int use_irq = host->irq != NO_IRQ && !bus->polled;
404 /* Setup mode & subaddress if any */
405 switch(bus->mode) {
406 case pmac_i2c_mode_dumb:
407 return -EINVAL;
408 case pmac_i2c_mode_std:
409 mode_reg |= KW_I2C_MODE_STANDARD;
410 if (subsize != 0)
411 return -EINVAL;
412 break;
413 case pmac_i2c_mode_stdsub:
414 mode_reg |= KW_I2C_MODE_STANDARDSUB;
415 if (subsize != 1)
416 return -EINVAL;
417 break;
418 case pmac_i2c_mode_combined:
419 mode_reg |= KW_I2C_MODE_COMBINED;
420 if (subsize != 1)
421 return -EINVAL;
422 break;
425 /* Setup channel & clear pending irqs */
426 kw_write_reg(reg_isr, kw_read_reg(reg_isr));
427 kw_write_reg(reg_mode, mode_reg | (bus->channel << 4));
428 kw_write_reg(reg_status, 0);
430 /* Set up address and r/w bit, strip possible stale bus number from
431 * address top bits
433 kw_write_reg(reg_addr, addrdir & 0xff);
435 /* Set up the sub address */
436 if ((mode_reg & KW_I2C_MODE_MODE_MASK) == KW_I2C_MODE_STANDARDSUB
437 || (mode_reg & KW_I2C_MODE_MODE_MASK) == KW_I2C_MODE_COMBINED)
438 kw_write_reg(reg_subaddr, subaddr);
440 /* Prepare for async operations */
441 host->data = data;
442 host->len = len;
443 host->state = state_addr;
444 host->result = 0;
445 host->rw = (addrdir & 1);
446 host->polled = bus->polled;
448 /* Enable interrupt if not using polled mode and interrupt is
449 * available
451 if (use_irq) {
452 /* Clear completion */
453 INIT_COMPLETION(host->complete);
454 /* Ack stale interrupts */
455 kw_write_reg(reg_isr, kw_read_reg(reg_isr));
456 /* Arm timeout */
457 host->timeout_timer.expires = jiffies + KW_POLL_TIMEOUT;
458 add_timer(&host->timeout_timer);
459 /* Enable emission */
460 kw_write_reg(reg_ier, KW_I2C_IRQ_MASK);
463 /* Start sending address */
464 kw_write_reg(reg_control, KW_I2C_CTL_XADDR);
466 /* Wait for completion */
467 if (use_irq)
468 wait_for_completion(&host->complete);
469 else {
470 while(host->state != state_idle) {
471 unsigned long flags;
473 u8 isr = kw_i2c_wait_interrupt(host);
474 spin_lock_irqsave(&host->lock, flags);
475 kw_i2c_handle_interrupt(host, isr);
476 spin_unlock_irqrestore(&host->lock, flags);
480 /* Disable emission */
481 kw_write_reg(reg_ier, 0);
483 return host->result;
486 static struct pmac_i2c_host_kw *__init kw_i2c_host_init(struct device_node *np)
488 struct pmac_i2c_host_kw *host;
489 u32 *psteps, *prate, *addrp, steps;
491 host = kzalloc(sizeof(struct pmac_i2c_host_kw), GFP_KERNEL);
492 if (host == NULL) {
493 printk(KERN_ERR "low_i2c: Can't allocate host for %s\n",
494 np->full_name);
495 return NULL;
498 /* Apple is kind enough to provide a valid AAPL,address property
499 * on all i2c keywest nodes so far ... we would have to fallback
500 * to macio parsing if that wasn't the case
502 addrp = (u32 *)get_property(np, "AAPL,address", NULL);
503 if (addrp == NULL) {
504 printk(KERN_ERR "low_i2c: Can't find address for %s\n",
505 np->full_name);
506 kfree(host);
507 return NULL;
509 init_MUTEX(&host->mutex);
510 init_completion(&host->complete);
511 spin_lock_init(&host->lock);
512 init_timer(&host->timeout_timer);
513 host->timeout_timer.function = kw_i2c_timeout;
514 host->timeout_timer.data = (unsigned long)host;
516 psteps = (u32 *)get_property(np, "AAPL,address-step", NULL);
517 steps = psteps ? (*psteps) : 0x10;
518 for (host->bsteps = 0; (steps & 0x01) == 0; host->bsteps++)
519 steps >>= 1;
520 /* Select interface rate */
521 host->speed = KW_I2C_MODE_25KHZ;
522 prate = (u32 *)get_property(np, "AAPL,i2c-rate", NULL);
523 if (prate) switch(*prate) {
524 case 100:
525 host->speed = KW_I2C_MODE_100KHZ;
526 break;
527 case 50:
528 host->speed = KW_I2C_MODE_50KHZ;
529 break;
530 case 25:
531 host->speed = KW_I2C_MODE_25KHZ;
532 break;
534 if (np->n_intrs > 0)
535 host->irq = np->intrs[0].line;
536 else
537 host->irq = NO_IRQ;
539 host->base = ioremap((*addrp), 0x1000);
540 if (host->base == NULL) {
541 printk(KERN_ERR "low_i2c: Can't map registers for %s\n",
542 np->full_name);
543 kfree(host);
544 return NULL;
547 /* Make sure IRA is disabled */
548 kw_write_reg(reg_ier, 0);
550 /* Request chip interrupt */
551 if (request_irq(host->irq, kw_i2c_irq, SA_SHIRQ, "keywest i2c", host))
552 host->irq = NO_IRQ;
554 printk(KERN_INFO "KeyWest i2c @0x%08x irq %d %s\n",
555 *addrp, host->irq, np->full_name);
557 return host;
561 static void __init kw_i2c_add(struct pmac_i2c_host_kw *host,
562 struct device_node *controller,
563 struct device_node *busnode,
564 int channel)
566 struct pmac_i2c_bus *bus;
568 bus = kzalloc(sizeof(struct pmac_i2c_bus), GFP_KERNEL);
569 if (bus == NULL)
570 return;
572 bus->controller = of_node_get(controller);
573 bus->busnode = of_node_get(busnode);
574 bus->type = pmac_i2c_bus_keywest;
575 bus->hostdata = host;
576 bus->channel = channel;
577 bus->mode = pmac_i2c_mode_std;
578 bus->open = kw_i2c_open;
579 bus->close = kw_i2c_close;
580 bus->xfer = kw_i2c_xfer;
581 init_MUTEX(&bus->sem);
582 if (controller == busnode)
583 bus->flags = pmac_i2c_multibus;
584 list_add(&bus->link, &pmac_i2c_busses);
586 printk(KERN_INFO " channel %d bus %s\n", channel,
587 (controller == busnode) ? "<multibus>" : busnode->full_name);
590 static void __init kw_i2c_probe(void)
592 struct device_node *np, *child, *parent;
594 /* Probe keywest-i2c busses */
595 for (np = NULL;
596 (np = of_find_compatible_node(np, "i2c","keywest-i2c")) != NULL;){
597 struct pmac_i2c_host_kw *host;
598 int multibus, chans, i;
600 /* Found one, init a host structure */
601 host = kw_i2c_host_init(np);
602 if (host == NULL)
603 continue;
605 /* Now check if we have a multibus setup (old style) or if we
606 * have proper bus nodes. Note that the "new" way (proper bus
607 * nodes) might cause us to not create some busses that are
608 * kept hidden in the device-tree. In the future, we might
609 * want to work around that by creating busses without a node
610 * but not for now
612 child = of_get_next_child(np, NULL);
613 multibus = !child || strcmp(child->name, "i2c-bus");
614 of_node_put(child);
616 /* For a multibus setup, we get the bus count based on the
617 * parent type
619 if (multibus) {
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 u32 *reg =
630 (u32 *)get_property(child, "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 init_MUTEX(&bus->sem);
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 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 thigns
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 = (u32 *)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 init_MUTEX(&bus->sem);
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 u32 *reg;
960 reg = (u32 *)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 u32 *reg = (u32 *)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 void pmac_i2c_attach_adapter(struct pmac_i2c_bus *bus,
1023 struct i2c_adapter *adapter)
1025 WARN_ON(bus->adapter != NULL);
1026 bus->adapter = adapter;
1028 EXPORT_SYMBOL_GPL(pmac_i2c_attach_adapter);
1030 void pmac_i2c_detach_adapter(struct pmac_i2c_bus *bus,
1031 struct i2c_adapter *adapter)
1033 WARN_ON(bus->adapter != adapter);
1034 bus->adapter = NULL;
1036 EXPORT_SYMBOL_GPL(pmac_i2c_detach_adapter);
1038 struct i2c_adapter *pmac_i2c_get_adapter(struct pmac_i2c_bus *bus)
1040 return bus->adapter;
1042 EXPORT_SYMBOL_GPL(pmac_i2c_get_adapter);
1044 struct pmac_i2c_bus *pmac_i2c_adapter_to_bus(struct i2c_adapter *adapter)
1046 struct pmac_i2c_bus *bus;
1048 list_for_each_entry(bus, &pmac_i2c_busses, link)
1049 if (bus->adapter == adapter)
1050 return bus;
1051 return NULL;
1053 EXPORT_SYMBOL_GPL(pmac_i2c_adapter_to_bus);
1055 extern int pmac_i2c_match_adapter(struct device_node *dev,
1056 struct i2c_adapter *adapter)
1058 struct pmac_i2c_bus *bus = pmac_i2c_find_bus(dev);
1060 if (bus == NULL)
1061 return 0;
1062 return (bus->adapter == adapter);
1064 EXPORT_SYMBOL_GPL(pmac_i2c_match_adapter);
1066 int pmac_low_i2c_lock(struct device_node *np)
1068 struct pmac_i2c_bus *bus, *found = NULL;
1070 list_for_each_entry(bus, &pmac_i2c_busses, link) {
1071 if (np == bus->controller) {
1072 found = bus;
1073 break;
1076 if (!found)
1077 return -ENODEV;
1078 return pmac_i2c_open(bus, 0);
1080 EXPORT_SYMBOL_GPL(pmac_low_i2c_lock);
1082 int pmac_low_i2c_unlock(struct device_node *np)
1084 struct pmac_i2c_bus *bus, *found = NULL;
1086 list_for_each_entry(bus, &pmac_i2c_busses, link) {
1087 if (np == bus->controller) {
1088 found = bus;
1089 break;
1092 if (!found)
1093 return -ENODEV;
1094 pmac_i2c_close(bus);
1095 return 0;
1097 EXPORT_SYMBOL_GPL(pmac_low_i2c_unlock);
1100 int pmac_i2c_open(struct pmac_i2c_bus *bus, int polled)
1102 int rc;
1104 down(&bus->sem);
1105 bus->polled = polled || pmac_i2c_force_poll;
1106 bus->opened = 1;
1107 bus->mode = pmac_i2c_mode_std;
1108 if (bus->open && (rc = bus->open(bus)) != 0) {
1109 bus->opened = 0;
1110 up(&bus->sem);
1111 return rc;
1113 return 0;
1115 EXPORT_SYMBOL_GPL(pmac_i2c_open);
1117 void pmac_i2c_close(struct pmac_i2c_bus *bus)
1119 WARN_ON(!bus->opened);
1120 if (bus->close)
1121 bus->close(bus);
1122 bus->opened = 0;
1123 up(&bus->sem);
1125 EXPORT_SYMBOL_GPL(pmac_i2c_close);
1127 int pmac_i2c_setmode(struct pmac_i2c_bus *bus, int mode)
1129 WARN_ON(!bus->opened);
1131 /* Report me if you see the error below as there might be a new
1132 * "combined4" mode that I need to implement for the SMU bus
1134 if (mode < pmac_i2c_mode_dumb || mode > pmac_i2c_mode_combined) {
1135 printk(KERN_ERR "low_i2c: Invalid mode %d requested on"
1136 " bus %s !\n", mode, bus->busnode->full_name);
1137 return -EINVAL;
1139 bus->mode = mode;
1141 return 0;
1143 EXPORT_SYMBOL_GPL(pmac_i2c_setmode);
1145 int pmac_i2c_xfer(struct pmac_i2c_bus *bus, u8 addrdir, int subsize,
1146 u32 subaddr, u8 *data, int len)
1148 int rc;
1150 WARN_ON(!bus->opened);
1152 DBG("xfer() chan=%d, addrdir=0x%x, mode=%d, subsize=%d, subaddr=0x%x,"
1153 " %d bytes, bus %s\n", bus->channel, addrdir, bus->mode, subsize,
1154 subaddr, len, bus->busnode->full_name);
1156 rc = bus->xfer(bus, addrdir, subsize, subaddr, data, len);
1158 #ifdef DEBUG
1159 if (rc)
1160 DBG("xfer error %d\n", rc);
1161 #endif
1162 return rc;
1164 EXPORT_SYMBOL_GPL(pmac_i2c_xfer);
1166 /* some quirks for platform function decoding */
1167 enum {
1168 pmac_i2c_quirk_invmask = 0x00000001u,
1171 static void pmac_i2c_devscan(void (*callback)(struct device_node *dev,
1172 int quirks))
1174 struct pmac_i2c_bus *bus;
1175 struct device_node *np;
1176 static struct whitelist_ent {
1177 char *name;
1178 char *compatible;
1179 int quirks;
1180 } whitelist[] = {
1181 /* XXX Study device-tree's & apple drivers are get the quirks
1182 * right !
1184 { "i2c-hwclock", NULL, pmac_i2c_quirk_invmask },
1185 { "i2c-cpu-voltage", NULL, 0},
1186 { "temp-monitor", NULL, 0 },
1187 { "supply-monitor", NULL, 0 },
1188 { NULL, NULL, 0 },
1191 /* Only some devices need to have platform functions instanciated
1192 * here. For now, we have a table. Others, like 9554 i2c GPIOs used
1193 * on Xserve, if we ever do a driver for them, will use their own
1194 * platform function instance
1196 list_for_each_entry(bus, &pmac_i2c_busses, link) {
1197 for (np = NULL;
1198 (np = of_get_next_child(bus->busnode, np)) != NULL;) {
1199 struct whitelist_ent *p;
1200 /* If multibus, check if device is on that bus */
1201 if (bus->flags & pmac_i2c_multibus)
1202 if (bus != pmac_i2c_find_bus(np))
1203 continue;
1204 for (p = whitelist; p->name != NULL; p++) {
1205 if (strcmp(np->name, p->name))
1206 continue;
1207 if (p->compatible &&
1208 !device_is_compatible(np, p->compatible))
1209 continue;
1210 callback(np, p->quirks);
1211 break;
1217 #define MAX_I2C_DATA 64
1219 struct pmac_i2c_pf_inst
1221 struct pmac_i2c_bus *bus;
1222 u8 addr;
1223 u8 buffer[MAX_I2C_DATA];
1224 u8 scratch[MAX_I2C_DATA];
1225 int bytes;
1226 int quirks;
1229 static void* pmac_i2c_do_begin(struct pmf_function *func, struct pmf_args *args)
1231 struct pmac_i2c_pf_inst *inst;
1232 struct pmac_i2c_bus *bus;
1234 bus = pmac_i2c_find_bus(func->node);
1235 if (bus == NULL) {
1236 printk(KERN_ERR "low_i2c: Can't find bus for %s (pfunc)\n",
1237 func->node->full_name);
1238 return NULL;
1240 if (pmac_i2c_open(bus, 0)) {
1241 printk(KERN_ERR "low_i2c: Can't open i2c bus for %s (pfunc)\n",
1242 func->node->full_name);
1243 return NULL;
1246 /* XXX might need GFP_ATOMIC when called during the suspend process,
1247 * but then, there are already lots of issues with suspending when
1248 * near OOM that need to be resolved, the allocator itself should
1249 * probably make GFP_NOIO implicit during suspend
1251 inst = kzalloc(sizeof(struct pmac_i2c_pf_inst), GFP_KERNEL);
1252 if (inst == NULL) {
1253 pmac_i2c_close(bus);
1254 return NULL;
1256 inst->bus = bus;
1257 inst->addr = pmac_i2c_get_dev_addr(func->node);
1258 inst->quirks = (int)(long)func->driver_data;
1259 return inst;
1262 static void pmac_i2c_do_end(struct pmf_function *func, void *instdata)
1264 struct pmac_i2c_pf_inst *inst = instdata;
1266 if (inst == NULL)
1267 return;
1268 pmac_i2c_close(inst->bus);
1269 if (inst)
1270 kfree(inst);
1273 static int pmac_i2c_do_read(PMF_STD_ARGS, u32 len)
1275 struct pmac_i2c_pf_inst *inst = instdata;
1277 inst->bytes = len;
1278 return pmac_i2c_xfer(inst->bus, inst->addr | pmac_i2c_read, 0, 0,
1279 inst->buffer, len);
1282 static int pmac_i2c_do_write(PMF_STD_ARGS, u32 len, const u8 *data)
1284 struct pmac_i2c_pf_inst *inst = instdata;
1286 return pmac_i2c_xfer(inst->bus, inst->addr | pmac_i2c_write, 0, 0,
1287 (u8 *)data, len);
1290 /* This function is used to do the masking & OR'ing for the "rmw" type
1291 * callbacks. Ze should apply the mask and OR in the values in the
1292 * buffer before writing back. The problem is that it seems that
1293 * various darwin drivers implement the mask/or differently, thus
1294 * we need to check the quirks first
1296 static void pmac_i2c_do_apply_rmw(struct pmac_i2c_pf_inst *inst,
1297 u32 len, const u8 *mask, const u8 *val)
1299 int i;
1301 if (inst->quirks & pmac_i2c_quirk_invmask) {
1302 for (i = 0; i < len; i ++)
1303 inst->scratch[i] = (inst->buffer[i] & mask[i]) | val[i];
1304 } else {
1305 for (i = 0; i < len; i ++)
1306 inst->scratch[i] = (inst->buffer[i] & ~mask[i])
1307 | (val[i] & mask[i]);
1311 static int pmac_i2c_do_rmw(PMF_STD_ARGS, u32 masklen, u32 valuelen,
1312 u32 totallen, const u8 *maskdata,
1313 const u8 *valuedata)
1315 struct pmac_i2c_pf_inst *inst = instdata;
1317 if (masklen > inst->bytes || valuelen > inst->bytes ||
1318 totallen > inst->bytes || valuelen > masklen)
1319 return -EINVAL;
1321 pmac_i2c_do_apply_rmw(inst, masklen, maskdata, valuedata);
1323 return pmac_i2c_xfer(inst->bus, inst->addr | pmac_i2c_write, 0, 0,
1324 inst->scratch, totallen);
1327 static int pmac_i2c_do_read_sub(PMF_STD_ARGS, u8 subaddr, u32 len)
1329 struct pmac_i2c_pf_inst *inst = instdata;
1331 inst->bytes = len;
1332 return pmac_i2c_xfer(inst->bus, inst->addr | pmac_i2c_read, 1, subaddr,
1333 inst->buffer, len);
1336 static int pmac_i2c_do_write_sub(PMF_STD_ARGS, u8 subaddr, u32 len,
1337 const u8 *data)
1339 struct pmac_i2c_pf_inst *inst = instdata;
1341 return pmac_i2c_xfer(inst->bus, inst->addr | pmac_i2c_write, 1,
1342 subaddr, (u8 *)data, len);
1345 static int pmac_i2c_do_set_mode(PMF_STD_ARGS, int mode)
1347 struct pmac_i2c_pf_inst *inst = instdata;
1349 return pmac_i2c_setmode(inst->bus, mode);
1352 static int pmac_i2c_do_rmw_sub(PMF_STD_ARGS, u8 subaddr, u32 masklen,
1353 u32 valuelen, u32 totallen, const u8 *maskdata,
1354 const u8 *valuedata)
1356 struct pmac_i2c_pf_inst *inst = instdata;
1358 if (masklen > inst->bytes || valuelen > inst->bytes ||
1359 totallen > inst->bytes || valuelen > masklen)
1360 return -EINVAL;
1362 pmac_i2c_do_apply_rmw(inst, masklen, maskdata, valuedata);
1364 return pmac_i2c_xfer(inst->bus, inst->addr | pmac_i2c_write, 1,
1365 subaddr, inst->scratch, totallen);
1368 static int pmac_i2c_do_mask_and_comp(PMF_STD_ARGS, u32 len,
1369 const u8 *maskdata,
1370 const u8 *valuedata)
1372 struct pmac_i2c_pf_inst *inst = instdata;
1373 int i, match;
1375 /* Get return value pointer, it's assumed to be a u32 */
1376 if (!args || !args->count || !args->u[0].p)
1377 return -EINVAL;
1379 /* Check buffer */
1380 if (len > inst->bytes)
1381 return -EINVAL;
1383 for (i = 0, match = 1; match && i < len; i ++)
1384 if ((inst->buffer[i] & maskdata[i]) != valuedata[i])
1385 match = 0;
1386 *args->u[0].p = match;
1387 return 0;
1390 static int pmac_i2c_do_delay(PMF_STD_ARGS, u32 duration)
1392 msleep((duration + 999) / 1000);
1393 return 0;
1397 static struct pmf_handlers pmac_i2c_pfunc_handlers = {
1398 .begin = pmac_i2c_do_begin,
1399 .end = pmac_i2c_do_end,
1400 .read_i2c = pmac_i2c_do_read,
1401 .write_i2c = pmac_i2c_do_write,
1402 .rmw_i2c = pmac_i2c_do_rmw,
1403 .read_i2c_sub = pmac_i2c_do_read_sub,
1404 .write_i2c_sub = pmac_i2c_do_write_sub,
1405 .rmw_i2c_sub = pmac_i2c_do_rmw_sub,
1406 .set_i2c_mode = pmac_i2c_do_set_mode,
1407 .mask_and_compare = pmac_i2c_do_mask_and_comp,
1408 .delay = pmac_i2c_do_delay,
1411 static void __init pmac_i2c_dev_create(struct device_node *np, int quirks)
1413 DBG("dev_create(%s)\n", np->full_name);
1415 pmf_register_driver(np, &pmac_i2c_pfunc_handlers,
1416 (void *)(long)quirks);
1419 static void __init pmac_i2c_dev_init(struct device_node *np, int quirks)
1421 DBG("dev_create(%s)\n", np->full_name);
1423 pmf_do_functions(np, NULL, 0, PMF_FLAGS_ON_INIT, NULL);
1426 static void pmac_i2c_dev_suspend(struct device_node *np, int quirks)
1428 DBG("dev_suspend(%s)\n", np->full_name);
1429 pmf_do_functions(np, NULL, 0, PMF_FLAGS_ON_SLEEP, NULL);
1432 static void pmac_i2c_dev_resume(struct device_node *np, int quirks)
1434 DBG("dev_resume(%s)\n", np->full_name);
1435 pmf_do_functions(np, NULL, 0, PMF_FLAGS_ON_WAKE, NULL);
1438 void pmac_pfunc_i2c_suspend(void)
1440 pmac_i2c_devscan(pmac_i2c_dev_suspend);
1443 void pmac_pfunc_i2c_resume(void)
1445 pmac_i2c_devscan(pmac_i2c_dev_resume);
1449 * Initialize us: probe all i2c busses on the machine, instantiate
1450 * busses and platform functions as needed.
1452 /* This is non-static as it might be called early by smp code */
1453 int __init pmac_i2c_init(void)
1455 static int i2c_inited;
1457 if (i2c_inited)
1458 return 0;
1459 i2c_inited = 1;
1461 /* Probe keywest-i2c busses */
1462 kw_i2c_probe();
1464 #ifdef CONFIG_ADB_PMU
1465 /* Probe PMU i2c busses */
1466 pmu_i2c_probe();
1467 #endif
1469 #ifdef CONFIG_PMAC_SMU
1470 /* Probe SMU i2c busses */
1471 smu_i2c_probe();
1472 #endif
1474 /* Now add plaform functions for some known devices */
1475 pmac_i2c_devscan(pmac_i2c_dev_create);
1477 return 0;
1479 arch_initcall(pmac_i2c_init);
1481 /* Since pmac_i2c_init can be called too early for the platform device
1482 * registration, we need to do it at a later time. In our case, subsys
1483 * happens to fit well, though I agree it's a bit of a hack...
1485 static int __init pmac_i2c_create_platform_devices(void)
1487 struct pmac_i2c_bus *bus;
1488 int i = 0;
1490 /* In the case where we are initialized from smp_init(), we must
1491 * not use the timer (and thus the irq). It's safe from now on
1492 * though
1494 pmac_i2c_force_poll = 0;
1496 /* Create platform devices */
1497 list_for_each_entry(bus, &pmac_i2c_busses, link) {
1498 bus->platform_dev =
1499 platform_device_alloc("i2c-powermac", i++);
1500 if (bus->platform_dev == NULL)
1501 return -ENOMEM;
1502 bus->platform_dev->dev.platform_data = bus;
1503 platform_device_add(bus->platform_dev);
1506 /* Now call platform "init" functions */
1507 pmac_i2c_devscan(pmac_i2c_dev_init);
1509 return 0;
1511 subsys_initcall(pmac_i2c_create_platform_devices);