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TOMOYO Linux Cross Reference
Linux/arch/powerpc/platforms/powermac/low_i2c.c

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

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