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