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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         struct lock_class_key   lock_key;
 94 
 95         /* ops */
 96         int (*open)(struct pmac_i2c_bus *bus);
 97         void (*close)(struct pmac_i2c_bus *bus);
 98         int (*xfer)(struct pmac_i2c_bus *bus, u8 addrdir, int subsize,
 99                     u32 subaddr, u8 *data, int len);
100 };
101 
102 static LIST_HEAD(pmac_i2c_busses);
103 
104 /*
105  * Keywest implementation
106  */
107 
108 struct pmac_i2c_host_kw
109 {
110         struct mutex            mutex;          /* Access mutex for use by
111                                                  * i2c-keywest */
112         void __iomem            *base;          /* register base address */
113         int                     bsteps;         /* register stepping */
114         int                     speed;          /* speed */
115         int                     irq;
116         u8                      *data;
117         unsigned                len;
118         int                     state;
119         int                     rw;
120         int                     polled;
121         int                     result;
122         struct completion       complete;
123         spinlock_t              lock;
124         struct timer_list       timeout_timer;
125 };
126 
127 /* Register indices */
128 typedef enum {
129         reg_mode = 0,
130         reg_control,
131         reg_status,
132         reg_isr,
133         reg_ier,
134         reg_addr,
135         reg_subaddr,
136         reg_data
137 } reg_t;
138 
139 /* The Tumbler audio equalizer can be really slow sometimes */
140 #define KW_POLL_TIMEOUT         (2*HZ)
141 
142 /* Mode register */
143 #define KW_I2C_MODE_100KHZ      0x00
144 #define KW_I2C_MODE_50KHZ       0x01
145 #define KW_I2C_MODE_25KHZ       0x02
146 #define KW_I2C_MODE_DUMB        0x00
147 #define KW_I2C_MODE_STANDARD    0x04
148 #define KW_I2C_MODE_STANDARDSUB 0x08
149 #define KW_I2C_MODE_COMBINED    0x0C
150 #define KW_I2C_MODE_MODE_MASK   0x0C
151 #define KW_I2C_MODE_CHAN_MASK   0xF0
152 
153 /* Control register */
154 #define KW_I2C_CTL_AAK          0x01
155 #define KW_I2C_CTL_XADDR        0x02
156 #define KW_I2C_CTL_STOP         0x04
157 #define KW_I2C_CTL_START        0x08
158 
159 /* Status register */
160 #define KW_I2C_STAT_BUSY        0x01
161 #define KW_I2C_STAT_LAST_AAK    0x02
162 #define KW_I2C_STAT_LAST_RW     0x04
163 #define KW_I2C_STAT_SDA         0x08
164 #define KW_I2C_STAT_SCL         0x10
165 
166 /* IER & ISR registers */
167 #define KW_I2C_IRQ_DATA         0x01
168 #define KW_I2C_IRQ_ADDR         0x02
169 #define KW_I2C_IRQ_STOP         0x04
170 #define KW_I2C_IRQ_START        0x08
171 #define KW_I2C_IRQ_MASK         0x0F
172 
173 /* State machine states */
174 enum {
175         state_idle,
176         state_addr,
177         state_read,
178         state_write,
179         state_stop,
180         state_dead
181 };
182 
183 #define WRONG_STATE(name) do {\
184                 printk(KERN_DEBUG "KW: wrong state. Got %s, state: %s " \
185                        "(isr: %02x)\n", \
186                        name, __kw_state_names[host->state], isr); \
187         } while(0)
188 
189 static const char *__kw_state_names[] = {
190         "state_idle",
191         "state_addr",
192         "state_read",
193         "state_write",
194         "state_stop",
195         "state_dead"
196 };
197 
198 static inline u8 __kw_read_reg(struct pmac_i2c_host_kw *host, reg_t reg)
199 {
200         return readb(host->base + (((unsigned int)reg) << host->bsteps));
201 }
202 
203 static inline void __kw_write_reg(struct pmac_i2c_host_kw *host,
204                                   reg_t reg, u8 val)
205 {
206         writeb(val, host->base + (((unsigned)reg) << host->bsteps));
207         (void)__kw_read_reg(host, reg_subaddr);
208 }
209 
210 #define kw_write_reg(reg, val)  __kw_write_reg(host, reg, val)
211 #define kw_read_reg(reg)        __kw_read_reg(host, reg)
212 
213 static u8 kw_i2c_wait_interrupt(struct pmac_i2c_host_kw *host)
214 {
215         int i, j;
216         u8 isr;
217         
218         for (i = 0; i < 1000; i++) {
219                 isr = kw_read_reg(reg_isr) & KW_I2C_IRQ_MASK;
220                 if (isr != 0)
221                         return isr;
222 
223                 /* This code is used with the timebase frozen, we cannot rely
224                  * on udelay nor schedule when in polled mode !
225                  * For now, just use a bogus loop....
226                  */
227                 if (host->polled) {
228                         for (j = 1; j < 100000; j++)
229                                 mb();
230                 } else
231                         msleep(1);
232         }
233         return isr;
234 }
235 
236 static void kw_i2c_do_stop(struct pmac_i2c_host_kw *host, int result)
237 {
238         kw_write_reg(reg_control, KW_I2C_CTL_STOP);
239         host->state = state_stop;
240         host->result = result;
241 }
242 
243 
244 static void kw_i2c_handle_interrupt(struct pmac_i2c_host_kw *host, u8 isr)
245 {
246         u8 ack;
247 
248         DBG_LOW("kw_handle_interrupt(%s, isr: %x)\n",
249                 __kw_state_names[host->state], isr);
250 
251         if (host->state == state_idle) {
252                 printk(KERN_WARNING "low_i2c: Keywest got an out of state"
253                        " interrupt, ignoring\n");
254                 kw_write_reg(reg_isr, isr);
255                 return;
256         }
257 
258         if (isr == 0) {
259                 printk(KERN_WARNING "low_i2c: Timeout in i2c transfer"
260                        " on keywest !\n");
261                 if (host->state != state_stop) {
262                         kw_i2c_do_stop(host, -EIO);
263                         return;
264                 }
265                 ack = kw_read_reg(reg_status);
266                 if (ack & KW_I2C_STAT_BUSY)
267                         kw_write_reg(reg_status, 0);
268                 host->state = state_idle;
269                 kw_write_reg(reg_ier, 0x00);
270                 if (!host->polled)
271                         complete(&host->complete);
272                 return;
273         }
274 
275         if (isr & KW_I2C_IRQ_ADDR) {
276                 ack = kw_read_reg(reg_status);
277                 if (host->state != state_addr) {
278                         WRONG_STATE("KW_I2C_IRQ_ADDR"); 
279                         kw_i2c_do_stop(host, -EIO);
280                 }
281                 if ((ack & KW_I2C_STAT_LAST_AAK) == 0) {
282                         host->result = -ENXIO;
283                         host->state = state_stop;
284                         DBG_LOW("KW: NAK on address\n");
285                 } else {
286                         if (host->len == 0)
287                                 kw_i2c_do_stop(host, 0);
288                         else if (host->rw) {
289                                 host->state = state_read;
290                                 if (host->len > 1)
291                                         kw_write_reg(reg_control,
292                                                      KW_I2C_CTL_AAK);
293                         } else {
294                                 host->state = state_write;
295                                 kw_write_reg(reg_data, *(host->data++));
296                                 host->len--;
297                         }
298                 }
299                 kw_write_reg(reg_isr, KW_I2C_IRQ_ADDR);
300         }
301 
302         if (isr & KW_I2C_IRQ_DATA) {
303                 if (host->state == state_read) {
304                         *(host->data++) = kw_read_reg(reg_data);
305                         host->len--;
306                         kw_write_reg(reg_isr, KW_I2C_IRQ_DATA);
307                         if (host->len == 0)
308                                 host->state = state_stop;
309                         else if (host->len == 1)
310                                 kw_write_reg(reg_control, 0);
311                 } else if (host->state == state_write) {
312                         ack = kw_read_reg(reg_status);
313                         if ((ack & KW_I2C_STAT_LAST_AAK) == 0) {
314                                 DBG_LOW("KW: nack on data write\n");
315                                 host->result = -EFBIG;
316                                 host->state = state_stop;
317                         } else if (host->len) {
318                                 kw_write_reg(reg_data, *(host->data++));
319                                 host->len--;
320                         } else
321                                 kw_i2c_do_stop(host, 0);
322                 } else {
323                         WRONG_STATE("KW_I2C_IRQ_DATA"); 
324                         if (host->state != state_stop)
325                                 kw_i2c_do_stop(host, -EIO);
326                 }
327                 kw_write_reg(reg_isr, KW_I2C_IRQ_DATA);
328         }
329 
330         if (isr & KW_I2C_IRQ_STOP) {
331                 kw_write_reg(reg_isr, KW_I2C_IRQ_STOP);
332                 if (host->state != state_stop) {
333                         WRONG_STATE("KW_I2C_IRQ_STOP");
334                         host->result = -EIO;
335                 }
336                 host->state = state_idle;
337                 if (!host->polled)
338                         complete(&host->complete);
339         }
340 
341         /* Below should only happen in manual mode which we don't use ... */
342         if (isr & KW_I2C_IRQ_START)
343                 kw_write_reg(reg_isr, KW_I2C_IRQ_START);
344 
345 }
346 
347 /* Interrupt handler */
348 static irqreturn_t kw_i2c_irq(int irq, void *dev_id)
349 {
350         struct pmac_i2c_host_kw *host = dev_id;
351         unsigned long flags;
352 
353         spin_lock_irqsave(&host->lock, flags);
354         del_timer(&host->timeout_timer);
355         kw_i2c_handle_interrupt(host, kw_read_reg(reg_isr));
356         if (host->state != state_idle) {
357                 host->timeout_timer.expires = jiffies + KW_POLL_TIMEOUT;
358                 add_timer(&host->timeout_timer);
359         }
360         spin_unlock_irqrestore(&host->lock, flags);
361         return IRQ_HANDLED;
362 }
363 
364 static void kw_i2c_timeout(unsigned long data)
365 {
366         struct pmac_i2c_host_kw *host = (struct pmac_i2c_host_kw *)data;
367         unsigned long flags;
368 
369         spin_lock_irqsave(&host->lock, flags);
370 
371         /*
372          * If the timer is pending, that means we raced with the
373          * irq, in which case we just return
374          */
375         if (timer_pending(&host->timeout_timer))
376                 goto skip;
377 
378         kw_i2c_handle_interrupt(host, kw_read_reg(reg_isr));
379         if (host->state != state_idle) {
380                 host->timeout_timer.expires = jiffies + KW_POLL_TIMEOUT;
381                 add_timer(&host->timeout_timer);
382         }
383  skip:
384         spin_unlock_irqrestore(&host->lock, flags);
385 }
386 
387 static int kw_i2c_open(struct pmac_i2c_bus *bus)
388 {
389         struct pmac_i2c_host_kw *host = bus->hostdata;
390         mutex_lock(&host->mutex);
391         return 0;
392 }
393 
394 static void kw_i2c_close(struct pmac_i2c_bus *bus)
395 {
396         struct pmac_i2c_host_kw *host = bus->hostdata;
397         mutex_unlock(&host->mutex);
398 }
399 
400 static int kw_i2c_xfer(struct pmac_i2c_bus *bus, u8 addrdir, int subsize,
401                        u32 subaddr, u8 *data, int len)
402 {
403         struct pmac_i2c_host_kw *host = bus->hostdata;
404         u8 mode_reg = host->speed;
405         int use_irq = host->irq && !bus->polled;
406 
407         /* Setup mode & subaddress if any */
408         switch(bus->mode) {
409         case pmac_i2c_mode_dumb:
410                 return -EINVAL;
411         case pmac_i2c_mode_std:
412                 mode_reg |= KW_I2C_MODE_STANDARD;
413                 if (subsize != 0)
414                         return -EINVAL;
415                 break;
416         case pmac_i2c_mode_stdsub:
417                 mode_reg |= KW_I2C_MODE_STANDARDSUB;
418                 if (subsize != 1)
419                         return -EINVAL;
420                 break;
421         case pmac_i2c_mode_combined:
422                 mode_reg |= KW_I2C_MODE_COMBINED;
423                 if (subsize != 1)
424                         return -EINVAL;
425                 break;
426         }
427 
428         /* Setup channel & clear pending irqs */
429         kw_write_reg(reg_isr, kw_read_reg(reg_isr));
430         kw_write_reg(reg_mode, mode_reg | (bus->channel << 4));
431         kw_write_reg(reg_status, 0);
432 
433         /* Set up address and r/w bit, strip possible stale bus number from
434          * address top bits
435          */
436         kw_write_reg(reg_addr, addrdir & 0xff);
437 
438         /* Set up the sub address */
439         if ((mode_reg & KW_I2C_MODE_MODE_MASK) == KW_I2C_MODE_STANDARDSUB
440             || (mode_reg & KW_I2C_MODE_MODE_MASK) == KW_I2C_MODE_COMBINED)
441                 kw_write_reg(reg_subaddr, subaddr);
442 
443         /* Prepare for async operations */
444         host->data = data;
445         host->len = len;
446         host->state = state_addr;
447         host->result = 0;
448         host->rw = (addrdir & 1);
449         host->polled = bus->polled;
450 
451         /* Enable interrupt if not using polled mode and interrupt is
452          * available
453          */
454         if (use_irq) {
455                 /* Clear completion */
456                 reinit_completion(&host->complete);
457                 /* Ack stale interrupts */
458                 kw_write_reg(reg_isr, kw_read_reg(reg_isr));
459                 /* Arm timeout */
460                 host->timeout_timer.expires = jiffies + KW_POLL_TIMEOUT;
461                 add_timer(&host->timeout_timer);
462                 /* Enable emission */
463                 kw_write_reg(reg_ier, KW_I2C_IRQ_MASK);
464         }
465 
466         /* Start sending address */
467         kw_write_reg(reg_control, KW_I2C_CTL_XADDR);
468 
469         /* Wait for completion */
470         if (use_irq)
471                 wait_for_completion(&host->complete);
472         else {
473                 while(host->state != state_idle) {
474                         unsigned long flags;
475 
476                         u8 isr = kw_i2c_wait_interrupt(host);
477                         spin_lock_irqsave(&host->lock, flags);
478                         kw_i2c_handle_interrupt(host, isr);
479                         spin_unlock_irqrestore(&host->lock, flags);
480                 }
481         }
482 
483         /* Disable emission */
484         kw_write_reg(reg_ier, 0);
485 
486         return host->result;
487 }
488 
489 static struct pmac_i2c_host_kw *__init kw_i2c_host_init(struct device_node *np)
490 {
491         struct pmac_i2c_host_kw *host;
492         const u32               *psteps, *prate, *addrp;
493         u32                     steps;
494 
495         host = kzalloc(sizeof(struct pmac_i2c_host_kw), GFP_KERNEL);
496         if (host == NULL) {
497                 printk(KERN_ERR "low_i2c: Can't allocate host for %s\n",
498                        np->full_name);
499                 return NULL;
500         }
501 
502         /* Apple is kind enough to provide a valid AAPL,address property
503          * on all i2c keywest nodes so far ... we would have to fallback
504          * to macio parsing if that wasn't the case
505          */
506         addrp = of_get_property(np, "AAPL,address", NULL);
507         if (addrp == NULL) {
508                 printk(KERN_ERR "low_i2c: Can't find address for %s\n",
509                        np->full_name);
510                 kfree(host);
511                 return NULL;
512         }
513         mutex_init(&host->mutex);
514         init_completion(&host->complete);
515         spin_lock_init(&host->lock);
516         init_timer(&host->timeout_timer);
517         host->timeout_timer.function = kw_i2c_timeout;
518         host->timeout_timer.data = (unsigned long)host;
519 
520         psteps = of_get_property(np, "AAPL,address-step", NULL);
521         steps = psteps ? (*psteps) : 0x10;
522         for (host->bsteps = 0; (steps & 0x01) == 0; host->bsteps++)
523                 steps >>= 1;
524         /* Select interface rate */
525         host->speed = KW_I2C_MODE_25KHZ;
526         prate = of_get_property(np, "AAPL,i2c-rate", NULL);
527         if (prate) switch(*prate) {
528         case 100:
529                 host->speed = KW_I2C_MODE_100KHZ;
530                 break;
531         case 50:
532                 host->speed = KW_I2C_MODE_50KHZ;
533                 break;
534         case 25:
535                 host->speed = KW_I2C_MODE_25KHZ;
536                 break;
537         }       
538         host->irq = irq_of_parse_and_map(np, 0);
539         if (!host->irq)
540                 printk(KERN_WARNING
541                        "low_i2c: Failed to map interrupt for %s\n",
542                        np->full_name);
543 
544         host->base = ioremap((*addrp), 0x1000);
545         if (host->base == NULL) {
546                 printk(KERN_ERR "low_i2c: Can't map registers for %s\n",
547                        np->full_name);
548                 kfree(host);
549                 return NULL;
550         }
551 
552         /* Make sure IRQ is disabled */
553         kw_write_reg(reg_ier, 0);
554 
555         /* Request chip interrupt. We set IRQF_NO_SUSPEND because we don't
556          * want that interrupt disabled between the 2 passes of driver
557          * suspend or we'll have issues running the pfuncs
558          */
559         if (request_irq(host->irq, kw_i2c_irq, IRQF_NO_SUSPEND,
560                         "keywest i2c", host))
561                 host->irq = 0;
562 
563         printk(KERN_INFO "KeyWest i2c @0x%08x irq %d %s\n",
564                *addrp, host->irq, np->full_name);
565 
566         return host;
567 }
568 
569 
570 static void __init kw_i2c_add(struct pmac_i2c_host_kw *host,
571                               struct device_node *controller,
572                               struct device_node *busnode,
573                               int channel)
574 {
575         struct pmac_i2c_bus *bus;
576 
577         bus = kzalloc(sizeof(struct pmac_i2c_bus), GFP_KERNEL);
578         if (bus == NULL)
579                 return;
580 
581         bus->controller = of_node_get(controller);
582         bus->busnode = of_node_get(busnode);
583         bus->type = pmac_i2c_bus_keywest;
584         bus->hostdata = host;
585         bus->channel = channel;
586         bus->mode = pmac_i2c_mode_std;
587         bus->open = kw_i2c_open;
588         bus->close = kw_i2c_close;
589         bus->xfer = kw_i2c_xfer;
590         mutex_init(&bus->mutex);
591         lockdep_set_class(&bus->mutex, &bus->lock_key);
592         if (controller == busnode)
593                 bus->flags = pmac_i2c_multibus;
594         list_add(&bus->link, &pmac_i2c_busses);
595 
596         printk(KERN_INFO " channel %d bus %s\n", channel,
597                (controller == busnode) ? "<multibus>" : busnode->full_name);
598 }
599 
600 static void __init kw_i2c_probe(void)
601 {
602         struct device_node *np, *child, *parent;
603 
604         /* Probe keywest-i2c busses */
605         for_each_compatible_node(np, "i2c","keywest-i2c") {
606                 struct pmac_i2c_host_kw *host;
607                 int multibus;
608 
609                 /* Found one, init a host structure */
610                 host = kw_i2c_host_init(np);
611                 if (host == NULL)
612                         continue;
613 
614                 /* Now check if we have a multibus setup (old style) or if we
615                  * have proper bus nodes. Note that the "new" way (proper bus
616                  * nodes) might cause us to not create some busses that are
617                  * kept hidden in the device-tree. In the future, we might
618                  * want to work around that by creating busses without a node
619                  * but not for now
620                  */
621                 child = of_get_next_child(np, NULL);
622                 multibus = !child || strcmp(child->name, "i2c-bus");
623                 of_node_put(child);
624 
625                 /* For a multibus setup, we get the bus count based on the
626                  * parent type
627                  */
628                 if (multibus) {
629                         int chans, i;
630 
631                         parent = of_get_parent(np);
632                         if (parent == NULL)
633                                 continue;
634                         chans = parent->name[0] == 'u' ? 2 : 1;
635                         for (i = 0; i < chans; i++)
636                                 kw_i2c_add(host, np, np, i);
637                 } else {
638                         for (child = NULL;
639                              (child = of_get_next_child(np, child)) != NULL;) {
640                                 const u32 *reg = of_get_property(child,
641                                                 "reg", NULL);
642                                 if (reg == NULL)
643                                         continue;
644                                 kw_i2c_add(host, np, child, *reg);
645                         }
646                 }
647         }
648 }
649 
650 
651 /*
652  *
653  * PMU implementation
654  *
655  */
656 
657 #ifdef CONFIG_ADB_PMU
658 
659 /*
660  * i2c command block to the PMU
661  */
662 struct pmu_i2c_hdr {
663         u8      bus;
664         u8      mode;
665         u8      bus2;
666         u8      address;
667         u8      sub_addr;
668         u8      comb_addr;
669         u8      count;
670         u8      data[];
671 };
672 
673 static void pmu_i2c_complete(struct adb_request *req)
674 {
675         complete(req->arg);
676 }
677 
678 static int pmu_i2c_xfer(struct pmac_i2c_bus *bus, u8 addrdir, int subsize,
679                         u32 subaddr, u8 *data, int len)
680 {
681         struct adb_request *req = bus->hostdata;
682         struct pmu_i2c_hdr *hdr = (struct pmu_i2c_hdr *)&req->data[1];
683         struct completion comp;
684         int read = addrdir & 1;
685         int retry;
686         int rc = 0;
687 
688         /* For now, limit ourselves to 16 bytes transfers */
689         if (len > 16)
690                 return -EINVAL;
691 
692         init_completion(&comp);
693 
694         for (retry = 0; retry < 16; retry++) {
695                 memset(req, 0, sizeof(struct adb_request));
696                 hdr->bus = bus->channel;
697                 hdr->count = len;
698 
699                 switch(bus->mode) {
700                 case pmac_i2c_mode_std:
701                         if (subsize != 0)
702                                 return -EINVAL;
703                         hdr->address = addrdir;
704                         hdr->mode = PMU_I2C_MODE_SIMPLE;
705                         break;
706                 case pmac_i2c_mode_stdsub:
707                 case pmac_i2c_mode_combined:
708                         if (subsize != 1)
709                                 return -EINVAL;
710                         hdr->address = addrdir & 0xfe;
711                         hdr->comb_addr = addrdir;
712                         hdr->sub_addr = subaddr;
713                         if (bus->mode == pmac_i2c_mode_stdsub)
714                                 hdr->mode = PMU_I2C_MODE_STDSUB;
715                         else
716                                 hdr->mode = PMU_I2C_MODE_COMBINED;
717                         break;
718                 default:
719                         return -EINVAL;
720                 }
721 
722                 reinit_completion(&comp);
723                 req->data[0] = PMU_I2C_CMD;
724                 req->reply[0] = 0xff;
725                 req->nbytes = sizeof(struct pmu_i2c_hdr) + 1;
726                 req->done = pmu_i2c_complete;
727                 req->arg = &comp;
728                 if (!read && len) {
729                         memcpy(hdr->data, data, len);
730                         req->nbytes += len;
731                 }
732                 rc = pmu_queue_request(req);
733                 if (rc)
734                         return rc;
735                 wait_for_completion(&comp);
736                 if (req->reply[0] == PMU_I2C_STATUS_OK)
737                         break;
738                 msleep(15);
739         }
740         if (req->reply[0] != PMU_I2C_STATUS_OK)
741                 return -EIO;
742 
743         for (retry = 0; retry < 16; retry++) {
744                 memset(req, 0, sizeof(struct adb_request));
745 
746                 /* I know that looks like a lot, slow as hell, but darwin
747                  * does it so let's be on the safe side for now
748                  */
749                 msleep(15);
750 
751                 hdr->bus = PMU_I2C_BUS_STATUS;
752 
753                 reinit_completion(&comp);
754                 req->data[0] = PMU_I2C_CMD;
755                 req->reply[0] = 0xff;
756                 req->nbytes = 2;
757                 req->done = pmu_i2c_complete;
758                 req->arg = &comp;
759                 rc = pmu_queue_request(req);
760                 if (rc)
761                         return rc;
762                 wait_for_completion(&comp);
763 
764                 if (req->reply[0] == PMU_I2C_STATUS_OK && !read)
765                         return 0;
766                 if (req->reply[0] == PMU_I2C_STATUS_DATAREAD && read) {
767                         int rlen = req->reply_len - 1;
768 
769                         if (rlen != len) {
770                                 printk(KERN_WARNING "low_i2c: PMU returned %d"
771                                        " bytes, expected %d !\n", rlen, len);
772                                 return -EIO;
773                         }
774                         if (len)
775                                 memcpy(data, &req->reply[1], len);
776                         return 0;
777                 }
778         }
779         return -EIO;
780 }
781 
782 static void __init pmu_i2c_probe(void)
783 {
784         struct pmac_i2c_bus *bus;
785         struct device_node *busnode;
786         int channel, sz;
787 
788         if (!pmu_present())
789                 return;
790 
791         /* There might or might not be a "pmu-i2c" node, we use that
792          * or via-pmu itself, whatever we find. I haven't seen a machine
793          * with separate bus nodes, so we assume a multibus setup
794          */
795         busnode = of_find_node_by_name(NULL, "pmu-i2c");
796         if (busnode == NULL)
797                 busnode = of_find_node_by_name(NULL, "via-pmu");
798         if (busnode == NULL)
799                 return;
800 
801         printk(KERN_INFO "PMU i2c %s\n", busnode->full_name);
802 
803         /*
804          * We add bus 1 and 2 only for now, bus 0 is "special"
805          */
806         for (channel = 1; channel <= 2; channel++) {
807                 sz = sizeof(struct pmac_i2c_bus) + sizeof(struct adb_request);
808                 bus = kzalloc(sz, GFP_KERNEL);
809                 if (bus == NULL)
810                         return;
811 
812                 bus->controller = busnode;
813                 bus->busnode = busnode;
814                 bus->type = pmac_i2c_bus_pmu;
815                 bus->channel = channel;
816                 bus->mode = pmac_i2c_mode_std;
817                 bus->hostdata = bus + 1;
818                 bus->xfer = pmu_i2c_xfer;
819                 mutex_init(&bus->mutex);
820                 lockdep_set_class(&bus->mutex, &bus->lock_key);
821                 bus->flags = pmac_i2c_multibus;
822                 list_add(&bus->link, &pmac_i2c_busses);
823 
824                 printk(KERN_INFO " channel %d bus <multibus>\n", channel);
825         }
826 }
827 
828 #endif /* CONFIG_ADB_PMU */
829 
830 
831 /*
832  *
833  * SMU implementation
834  *
835  */
836 
837 #ifdef CONFIG_PMAC_SMU
838 
839 static void smu_i2c_complete(struct smu_i2c_cmd *cmd, void *misc)
840 {
841         complete(misc);
842 }
843 
844 static int smu_i2c_xfer(struct pmac_i2c_bus *bus, u8 addrdir, int subsize,
845                         u32 subaddr, u8 *data, int len)
846 {
847         struct smu_i2c_cmd *cmd = bus->hostdata;
848         struct completion comp;
849         int read = addrdir & 1;
850         int rc = 0;
851 
852         if ((read && len > SMU_I2C_READ_MAX) ||
853             ((!read) && len > SMU_I2C_WRITE_MAX))
854                 return -EINVAL;
855 
856         memset(cmd, 0, sizeof(struct smu_i2c_cmd));
857         cmd->info.bus = bus->channel;
858         cmd->info.devaddr = addrdir;
859         cmd->info.datalen = len;
860 
861         switch(bus->mode) {
862         case pmac_i2c_mode_std:
863                 if (subsize != 0)
864                         return -EINVAL;
865                 cmd->info.type = SMU_I2C_TRANSFER_SIMPLE;
866                 break;
867         case pmac_i2c_mode_stdsub:
868         case pmac_i2c_mode_combined:
869                 if (subsize > 3 || subsize < 1)
870                         return -EINVAL;
871                 cmd->info.sublen = subsize;
872                 /* that's big-endian only but heh ! */
873                 memcpy(&cmd->info.subaddr, ((char *)&subaddr) + (4 - subsize),
874                        subsize);
875                 if (bus->mode == pmac_i2c_mode_stdsub)
876                         cmd->info.type = SMU_I2C_TRANSFER_STDSUB;
877                 else
878                         cmd->info.type = SMU_I2C_TRANSFER_COMBINED;
879                 break;
880         default:
881                 return -EINVAL;
882         }
883         if (!read && len)
884                 memcpy(cmd->info.data, data, len);
885 
886         init_completion(&comp);
887         cmd->done = smu_i2c_complete;
888         cmd->misc = &comp;
889         rc = smu_queue_i2c(cmd);
890         if (rc < 0)
891                 return rc;
892         wait_for_completion(&comp);
893         rc = cmd->status;
894 
895         if (read && len)
896                 memcpy(data, cmd->info.data, len);
897         return rc < 0 ? rc : 0;
898 }
899 
900 static void __init smu_i2c_probe(void)
901 {
902         struct device_node *controller, *busnode;
903         struct pmac_i2c_bus *bus;
904         const u32 *reg;
905         int sz;
906 
907         if (!smu_present())
908                 return;
909 
910         controller = of_find_node_by_name(NULL, "smu-i2c-control");
911         if (controller == NULL)
912                 controller = of_find_node_by_name(NULL, "smu");
913         if (controller == NULL)
914                 return;
915 
916         printk(KERN_INFO "SMU i2c %s\n", controller->full_name);
917 
918         /* Look for childs, note that they might not be of the right
919          * type as older device trees mix i2c busses and other things
920          * at the same level
921          */
922         for (busnode = NULL;
923              (busnode = of_get_next_child(controller, busnode)) != NULL;) {
924                 if (strcmp(busnode->type, "i2c") &&
925                     strcmp(busnode->type, "i2c-bus"))
926                         continue;
927                 reg = of_get_property(busnode, "reg", NULL);
928                 if (reg == NULL)
929                         continue;
930 
931                 sz = sizeof(struct pmac_i2c_bus) + sizeof(struct smu_i2c_cmd);
932                 bus = kzalloc(sz, GFP_KERNEL);
933                 if (bus == NULL)
934                         return;
935 
936                 bus->controller = controller;
937                 bus->busnode = of_node_get(busnode);
938                 bus->type = pmac_i2c_bus_smu;
939                 bus->channel = *reg;
940                 bus->mode = pmac_i2c_mode_std;
941                 bus->hostdata = bus + 1;
942                 bus->xfer = smu_i2c_xfer;
943                 mutex_init(&bus->mutex);
944                 lockdep_set_class(&bus->mutex, &bus->lock_key);
945                 bus->flags = 0;
946                 list_add(&bus->link, &pmac_i2c_busses);
947 
948                 printk(KERN_INFO " channel %x bus %s\n",
949                        bus->channel, busnode->full_name);
950         }
951 }
952 
953 #endif /* CONFIG_PMAC_SMU */
954 
955 /*
956  *
957  * Core code
958  *
959  */
960 
961 
962 struct pmac_i2c_bus *pmac_i2c_find_bus(struct device_node *node)
963 {
964         struct device_node *p = of_node_get(node);
965         struct device_node *prev = NULL;
966         struct pmac_i2c_bus *bus;
967 
968         while(p) {
969                 list_for_each_entry(bus, &pmac_i2c_busses, link) {
970                         if (p == bus->busnode) {
971                                 if (prev && bus->flags & pmac_i2c_multibus) {
972                                         const u32 *reg;
973                                         reg = of_get_property(prev, "reg",
974                                                                 NULL);
975                                         if (!reg)
976                                                 continue;
977                                         if (((*reg) >> 8) != bus->channel)
978                                                 continue;
979                                 }
980                                 of_node_put(p);
981                                 of_node_put(prev);
982                                 return bus;
983                         }
984                 }
985                 of_node_put(prev);
986                 prev = p;
987                 p = of_get_parent(p);
988         }
989         return NULL;
990 }
991 EXPORT_SYMBOL_GPL(pmac_i2c_find_bus);
992 
993 u8 pmac_i2c_get_dev_addr(struct device_node *device)
994 {
995         const u32 *reg = of_get_property(device, "reg", NULL);
996 
997         if (reg == NULL)
998                 return 0;
999 
1000         return (*reg) & 0xff;
1001 }
1002 EXPORT_SYMBOL_GPL(pmac_i2c_get_dev_addr);
1003 
1004 struct device_node *pmac_i2c_get_controller(struct pmac_i2c_bus *bus)
1005 {
1006         return bus->controller;
1007 }
1008 EXPORT_SYMBOL_GPL(pmac_i2c_get_controller);
1009 
1010 struct device_node *pmac_i2c_get_bus_node(struct pmac_i2c_bus *bus)
1011 {
1012         return bus->busnode;
1013 }
1014 EXPORT_SYMBOL_GPL(pmac_i2c_get_bus_node);
1015 
1016 int pmac_i2c_get_type(struct pmac_i2c_bus *bus)
1017 {
1018         return bus->type;
1019 }
1020 EXPORT_SYMBOL_GPL(pmac_i2c_get_type);
1021 
1022 int pmac_i2c_get_flags(struct pmac_i2c_bus *bus)
1023 {
1024         return bus->flags;
1025 }
1026 EXPORT_SYMBOL_GPL(pmac_i2c_get_flags);
1027 
1028 int pmac_i2c_get_channel(struct pmac_i2c_bus *bus)
1029 {
1030         return bus->channel;
1031 }
1032 EXPORT_SYMBOL_GPL(pmac_i2c_get_channel);
1033 
1034 
1035 struct i2c_adapter *pmac_i2c_get_adapter(struct pmac_i2c_bus *bus)
1036 {
1037         return &bus->adapter;
1038 }
1039 EXPORT_SYMBOL_GPL(pmac_i2c_get_adapter);
1040 
1041 struct pmac_i2c_bus *pmac_i2c_adapter_to_bus(struct i2c_adapter *adapter)
1042 {
1043         struct pmac_i2c_bus *bus;
1044 
1045         list_for_each_entry(bus, &pmac_i2c_busses, link)
1046                 if (&bus->adapter == adapter)
1047                         return bus;
1048         return NULL;
1049 }
1050 EXPORT_SYMBOL_GPL(pmac_i2c_adapter_to_bus);
1051 
1052 int pmac_i2c_match_adapter(struct device_node *dev, struct i2c_adapter *adapter)
1053 {
1054         struct pmac_i2c_bus *bus = pmac_i2c_find_bus(dev);
1055 
1056         if (bus == NULL)
1057                 return 0;
1058         return (&bus->adapter == adapter);
1059 }
1060 EXPORT_SYMBOL_GPL(pmac_i2c_match_adapter);
1061 
1062 int pmac_low_i2c_lock(struct device_node *np)
1063 {
1064         struct pmac_i2c_bus *bus, *found = NULL;
1065 
1066         list_for_each_entry(bus, &pmac_i2c_busses, link) {
1067                 if (np == bus->controller) {
1068                         found = bus;
1069                         break;
1070                 }
1071         }
1072         if (!found)
1073                 return -ENODEV;
1074         return pmac_i2c_open(bus, 0);
1075 }
1076 EXPORT_SYMBOL_GPL(pmac_low_i2c_lock);
1077 
1078 int pmac_low_i2c_unlock(struct device_node *np)
1079 {
1080         struct pmac_i2c_bus *bus, *found = NULL;
1081 
1082         list_for_each_entry(bus, &pmac_i2c_busses, link) {
1083                 if (np == bus->controller) {
1084                         found = bus;
1085                         break;
1086                 }
1087         }
1088         if (!found)
1089                 return -ENODEV;
1090         pmac_i2c_close(bus);
1091         return 0;
1092 }
1093 EXPORT_SYMBOL_GPL(pmac_low_i2c_unlock);
1094 
1095 
1096 int pmac_i2c_open(struct pmac_i2c_bus *bus, int polled)
1097 {
1098         int rc;
1099 
1100         mutex_lock(&bus->mutex);
1101         bus->polled = polled || pmac_i2c_force_poll;
1102         bus->opened = 1;
1103         bus->mode = pmac_i2c_mode_std;
1104         if (bus->open && (rc = bus->open(bus)) != 0) {
1105                 bus->opened = 0;
1106                 mutex_unlock(&bus->mutex);
1107                 return rc;
1108         }
1109         return 0;
1110 }
1111 EXPORT_SYMBOL_GPL(pmac_i2c_open);
1112 
1113 void pmac_i2c_close(struct pmac_i2c_bus *bus)
1114 {
1115         WARN_ON(!bus->opened);
1116         if (bus->close)
1117                 bus->close(bus);
1118         bus->opened = 0;
1119         mutex_unlock(&bus->mutex);
1120 }
1121 EXPORT_SYMBOL_GPL(pmac_i2c_close);
1122 
1123 int pmac_i2c_setmode(struct pmac_i2c_bus *bus, int mode)
1124 {
1125         WARN_ON(!bus->opened);
1126 
1127         /* Report me if you see the error below as there might be a new
1128          * "combined4" mode that I need to implement for the SMU bus
1129          */
1130         if (mode < pmac_i2c_mode_dumb || mode > pmac_i2c_mode_combined) {
1131                 printk(KERN_ERR "low_i2c: Invalid mode %d requested on"
1132                        " bus %s !\n", mode, bus->busnode->full_name);
1133                 return -EINVAL;
1134         }
1135         bus->mode = mode;
1136 
1137         return 0;
1138 }
1139 EXPORT_SYMBOL_GPL(pmac_i2c_setmode);
1140 
1141 int pmac_i2c_xfer(struct pmac_i2c_bus *bus, u8 addrdir, int subsize,
1142                   u32 subaddr, u8 *data, int len)
1143 {
1144         int rc;
1145 
1146         WARN_ON(!bus->opened);
1147 
1148         DBG("xfer() chan=%d, addrdir=0x%x, mode=%d, subsize=%d, subaddr=0x%x,"
1149             " %d bytes, bus %s\n", bus->channel, addrdir, bus->mode, subsize,
1150             subaddr, len, bus->busnode->full_name);
1151 
1152         rc = bus->xfer(bus, addrdir, subsize, subaddr, data, len);
1153 
1154 #ifdef DEBUG
1155         if (rc)
1156                 DBG("xfer error %d\n", rc);
1157 #endif
1158         return rc;
1159 }
1160 EXPORT_SYMBOL_GPL(pmac_i2c_xfer);
1161 
1162 /* some quirks for platform function decoding */
1163 enum {
1164         pmac_i2c_quirk_invmask = 0x00000001u,
1165         pmac_i2c_quirk_skip = 0x00000002u,
1166 };
1167 
1168 static void pmac_i2c_devscan(void (*callback)(struct device_node *dev,
1169                                               int quirks))
1170 {
1171         struct pmac_i2c_bus *bus;
1172         struct device_node *np;
1173         static struct whitelist_ent {
1174                 char *name;
1175                 char *compatible;
1176                 int quirks;
1177         } whitelist[] = {
1178                 /* XXX Study device-tree's & apple drivers are get the quirks
1179                  * right !
1180                  */
1181                 /* Workaround: It seems that running the clockspreading
1182                  * properties on the eMac will cause lockups during boot.
1183                  * The machine seems to work fine without that. So for now,
1184                  * let's make sure i2c-hwclock doesn't match about "imic"
1185                  * clocks and we'll figure out if we really need to do
1186                  * something special about those later.
1187                  */
1188                 { "i2c-hwclock", "imic5002", pmac_i2c_quirk_skip },
1189                 { "i2c-hwclock", "imic5003", pmac_i2c_quirk_skip },
1190                 { "i2c-hwclock", NULL, pmac_i2c_quirk_invmask },
1191                 { "i2c-cpu-voltage", NULL, 0},
1192                 {  "temp-monitor", NULL, 0 },
1193                 {  "supply-monitor", NULL, 0 },
1194                 { NULL, NULL, 0 },
1195         };
1196 
1197         /* Only some devices need to have platform functions instanciated
1198          * here. For now, we have a table. Others, like 9554 i2c GPIOs used
1199          * on Xserve, if we ever do a driver for them, will use their own
1200          * platform function instance
1201          */
1202         list_for_each_entry(bus, &pmac_i2c_busses, link) {
1203                 for (np = NULL;
1204                      (np = of_get_next_child(bus->busnode, np)) != NULL;) {
1205                         struct whitelist_ent *p;
1206                         /* If multibus, check if device is on that bus */
1207                         if (bus->flags & pmac_i2c_multibus)
1208                                 if (bus != pmac_i2c_find_bus(np))
1209                                         continue;
1210                         for (p = whitelist; p->name != NULL; p++) {
1211                                 if (strcmp(np->name, p->name))
1212                                         continue;
1213                                 if (p->compatible &&
1214                                     !of_device_is_compatible(np, p->compatible))
1215                                         continue;
1216                                 if (p->quirks & pmac_i2c_quirk_skip)
1217                                         break;
1218                                 callback(np, p->quirks);
1219                                 break;
1220                         }
1221                 }
1222         }
1223 }
1224 
1225 #define MAX_I2C_DATA    64
1226 
1227 struct pmac_i2c_pf_inst
1228 {
1229         struct pmac_i2c_bus     *bus;
1230         u8                      addr;
1231         u8                      buffer[MAX_I2C_DATA];
1232         u8                      scratch[MAX_I2C_DATA];
1233         int                     bytes;
1234         int                     quirks;
1235 };
1236 
1237 static void* pmac_i2c_do_begin(struct pmf_function *func, struct pmf_args *args)
1238 {
1239         struct pmac_i2c_pf_inst *inst;
1240         struct pmac_i2c_bus     *bus;
1241 
1242         bus = pmac_i2c_find_bus(func->node);
1243         if (bus == NULL) {
1244                 printk(KERN_ERR "low_i2c: Can't find bus for %s (pfunc)\n",
1245                        func->node->full_name);
1246                 return NULL;
1247         }
1248         if (pmac_i2c_open(bus, 0)) {
1249                 printk(KERN_ERR "low_i2c: Can't open i2c bus for %s (pfunc)\n",
1250                        func->node->full_name);
1251                 return NULL;
1252         }
1253 
1254         /* XXX might need GFP_ATOMIC when called during the suspend process,
1255          * but then, there are already lots of issues with suspending when
1256          * near OOM that need to be resolved, the allocator itself should
1257          * probably make GFP_NOIO implicit during suspend
1258          */
1259         inst = kzalloc(sizeof(struct pmac_i2c_pf_inst), GFP_KERNEL);
1260         if (inst == NULL) {
1261                 pmac_i2c_close(bus);
1262                 return NULL;
1263         }
1264         inst->bus = bus;
1265         inst->addr = pmac_i2c_get_dev_addr(func->node);
1266         inst->quirks = (int)(long)func->driver_data;
1267         return inst;
1268 }
1269 
1270 static void pmac_i2c_do_end(struct pmf_function *func, void *instdata)
1271 {
1272         struct pmac_i2c_pf_inst *inst = instdata;
1273 
1274         if (inst == NULL)
1275                 return;
1276         pmac_i2c_close(inst->bus);
1277         kfree(inst);
1278 }
1279 
1280 static int pmac_i2c_do_read(PMF_STD_ARGS, u32 len)
1281 {
1282         struct pmac_i2c_pf_inst *inst = instdata;
1283 
1284         inst->bytes = len;
1285         return pmac_i2c_xfer(inst->bus, inst->addr | pmac_i2c_read, 0, 0,
1286                              inst->buffer, len);
1287 }
1288 
1289 static int pmac_i2c_do_write(PMF_STD_ARGS, u32 len, const u8 *data)
1290 {
1291         struct pmac_i2c_pf_inst *inst = instdata;
1292 
1293         return pmac_i2c_xfer(inst->bus, inst->addr | pmac_i2c_write, 0, 0,
1294                              (u8 *)data, len);
1295 }
1296 
1297 /* This function is used to do the masking & OR'ing for the "rmw" type
1298  * callbacks. Ze should apply the mask and OR in the values in the
1299  * buffer before writing back. The problem is that it seems that
1300  * various darwin drivers implement the mask/or differently, thus
1301  * we need to check the quirks first
1302  */
1303 static void pmac_i2c_do_apply_rmw(struct pmac_i2c_pf_inst *inst,
1304                                   u32 len, const u8 *mask, const u8 *val)
1305 {
1306         int i;
1307 
1308         if (inst->quirks & pmac_i2c_quirk_invmask) {
1309                 for (i = 0; i < len; i ++)
1310                         inst->scratch[i] = (inst->buffer[i] & mask[i]) | val[i];
1311         } else {
1312                 for (i = 0; i < len; i ++)
1313                         inst->scratch[i] = (inst->buffer[i] & ~mask[i])
1314                                 | (val[i] & mask[i]);
1315         }
1316 }
1317 
1318 static int pmac_i2c_do_rmw(PMF_STD_ARGS, u32 masklen, u32 valuelen,
1319                            u32 totallen, const u8 *maskdata,
1320                            const u8 *valuedata)
1321 {
1322         struct pmac_i2c_pf_inst *inst = instdata;
1323 
1324         if (masklen > inst->bytes || valuelen > inst->bytes ||
1325             totallen > inst->bytes || valuelen > masklen)
1326                 return -EINVAL;
1327 
1328         pmac_i2c_do_apply_rmw(inst, masklen, maskdata, valuedata);
1329 
1330         return pmac_i2c_xfer(inst->bus, inst->addr | pmac_i2c_write, 0, 0,
1331                              inst->scratch, totallen);
1332 }
1333 
1334 static int pmac_i2c_do_read_sub(PMF_STD_ARGS, u8 subaddr, u32 len)
1335 {
1336         struct pmac_i2c_pf_inst *inst = instdata;
1337 
1338         inst->bytes = len;
1339         return pmac_i2c_xfer(inst->bus, inst->addr | pmac_i2c_read, 1, subaddr,
1340                              inst->buffer, len);
1341 }
1342 
1343 static int pmac_i2c_do_write_sub(PMF_STD_ARGS, u8 subaddr, u32 len,
1344                                      const u8 *data)
1345 {
1346         struct pmac_i2c_pf_inst *inst = instdata;
1347 
1348         return pmac_i2c_xfer(inst->bus, inst->addr | pmac_i2c_write, 1,
1349                              subaddr, (u8 *)data, len);
1350 }
1351 
1352 static int pmac_i2c_do_set_mode(PMF_STD_ARGS, int mode)
1353 {
1354         struct pmac_i2c_pf_inst *inst = instdata;
1355 
1356         return pmac_i2c_setmode(inst->bus, mode);
1357 }
1358 
1359 static int pmac_i2c_do_rmw_sub(PMF_STD_ARGS, u8 subaddr, u32 masklen,
1360                                u32 valuelen, u32 totallen, const u8 *maskdata,
1361                                const u8 *valuedata)
1362 {
1363         struct pmac_i2c_pf_inst *inst = instdata;
1364 
1365         if (masklen > inst->bytes || valuelen > inst->bytes ||
1366             totallen > inst->bytes || valuelen > masklen)
1367                 return -EINVAL;
1368 
1369         pmac_i2c_do_apply_rmw(inst, masklen, maskdata, valuedata);
1370 
1371         return pmac_i2c_xfer(inst->bus, inst->addr | pmac_i2c_write, 1,
1372                              subaddr, inst->scratch, totallen);
1373 }
1374 
1375 static int pmac_i2c_do_mask_and_comp(PMF_STD_ARGS, u32 len,
1376                                      const u8 *maskdata,
1377                                      const u8 *valuedata)
1378 {
1379         struct pmac_i2c_pf_inst *inst = instdata;
1380         int i, match;
1381 
1382         /* Get return value pointer, it's assumed to be a u32 */
1383         if (!args || !args->count || !args->u[0].p)
1384                 return -EINVAL;
1385 
1386         /* Check buffer */
1387         if (len > inst->bytes)
1388                 return -EINVAL;
1389 
1390         for (i = 0, match = 1; match && i < len; i ++)
1391                 if ((inst->buffer[i] & maskdata[i]) != valuedata[i])
1392                         match = 0;
1393         *args->u[0].p = match;
1394         return 0;
1395 }
1396 
1397 static int pmac_i2c_do_delay(PMF_STD_ARGS, u32 duration)
1398 {
1399         msleep((duration + 999) / 1000);
1400         return 0;
1401 }
1402 
1403 
1404 static struct pmf_handlers pmac_i2c_pfunc_handlers = {
1405         .begin                  = pmac_i2c_do_begin,
1406         .end                    = pmac_i2c_do_end,
1407         .read_i2c               = pmac_i2c_do_read,
1408         .write_i2c              = pmac_i2c_do_write,
1409         .rmw_i2c                = pmac_i2c_do_rmw,
1410         .read_i2c_sub           = pmac_i2c_do_read_sub,
1411         .write_i2c_sub          = pmac_i2c_do_write_sub,
1412         .rmw_i2c_sub            = pmac_i2c_do_rmw_sub,
1413         .set_i2c_mode           = pmac_i2c_do_set_mode,
1414         .mask_and_compare       = pmac_i2c_do_mask_and_comp,
1415         .delay                  = pmac_i2c_do_delay,
1416 };
1417 
1418 static void __init pmac_i2c_dev_create(struct device_node *np, int quirks)
1419 {
1420         DBG("dev_create(%s)\n", np->full_name);
1421 
1422         pmf_register_driver(np, &pmac_i2c_pfunc_handlers,
1423                             (void *)(long)quirks);
1424 }
1425 
1426 static void __init pmac_i2c_dev_init(struct device_node *np, int quirks)
1427 {
1428         DBG("dev_create(%s)\n", np->full_name);
1429 
1430         pmf_do_functions(np, NULL, 0, PMF_FLAGS_ON_INIT, NULL);
1431 }
1432 
1433 static void pmac_i2c_dev_suspend(struct device_node *np, int quirks)
1434 {
1435         DBG("dev_suspend(%s)\n", np->full_name);
1436         pmf_do_functions(np, NULL, 0, PMF_FLAGS_ON_SLEEP, NULL);
1437 }
1438 
1439 static void pmac_i2c_dev_resume(struct device_node *np, int quirks)
1440 {
1441         DBG("dev_resume(%s)\n", np->full_name);
1442         pmf_do_functions(np, NULL, 0, PMF_FLAGS_ON_WAKE, NULL);
1443 }
1444 
1445 void pmac_pfunc_i2c_suspend(void)
1446 {
1447         pmac_i2c_devscan(pmac_i2c_dev_suspend);
1448 }
1449 
1450 void pmac_pfunc_i2c_resume(void)
1451 {
1452         pmac_i2c_devscan(pmac_i2c_dev_resume);
1453 }
1454 
1455 /*
1456  * Initialize us: probe all i2c busses on the machine, instantiate
1457  * busses and platform functions as needed.
1458  */
1459 /* This is non-static as it might be called early by smp code */
1460 int __init pmac_i2c_init(void)
1461 {
1462         static int i2c_inited;
1463 
1464         if (i2c_inited)
1465                 return 0;
1466         i2c_inited = 1;
1467 
1468         /* Probe keywest-i2c busses */
1469         kw_i2c_probe();
1470 
1471 #ifdef CONFIG_ADB_PMU
1472         /* Probe PMU i2c busses */
1473         pmu_i2c_probe();
1474 #endif
1475 
1476 #ifdef CONFIG_PMAC_SMU
1477         /* Probe SMU i2c busses */
1478         smu_i2c_probe();
1479 #endif
1480 
1481         /* Now add plaform functions for some known devices */
1482         pmac_i2c_devscan(pmac_i2c_dev_create);
1483 
1484         return 0;
1485 }
1486 machine_arch_initcall(powermac, pmac_i2c_init);
1487 
1488 /* Since pmac_i2c_init can be called too early for the platform device
1489  * registration, we need to do it at a later time. In our case, subsys
1490  * happens to fit well, though I agree it's a bit of a hack...
1491  */
1492 static int __init pmac_i2c_create_platform_devices(void)
1493 {
1494         struct pmac_i2c_bus *bus;
1495         int i = 0;
1496 
1497         /* In the case where we are initialized from smp_init(), we must
1498          * not use the timer (and thus the irq). It's safe from now on
1499          * though
1500          */
1501         pmac_i2c_force_poll = 0;
1502 
1503         /* Create platform devices */
1504         list_for_each_entry(bus, &pmac_i2c_busses, link) {
1505                 bus->platform_dev =
1506                         platform_device_alloc("i2c-powermac", i++);
1507                 if (bus->platform_dev == NULL)
1508                         return -ENOMEM;
1509                 bus->platform_dev->dev.platform_data = bus;
1510                 bus->platform_dev->dev.of_node = bus->busnode;
1511                 platform_device_add(bus->platform_dev);
1512         }
1513 
1514         /* Now call platform "init" functions */
1515         pmac_i2c_devscan(pmac_i2c_dev_init);
1516 
1517         return 0;
1518 }
1519 machine_subsys_initcall(powermac, pmac_i2c_create_platform_devices);
1520 

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