[POWERPC] Add missing of_node_put in drivers/macintosh/smu.c
[linux-2.6.git] / drivers / macintosh / smu.c
1 /*
2  * PowerMac G5 SMU driver
3  *
4  * Copyright 2004 J. Mayer <l_indien@magic.fr>
5  * Copyright 2005 Benjamin Herrenschmidt, IBM Corp.
6  *
7  * Released under the term of the GNU GPL v2.
8  */
9
10 /*
11  * TODO:
12  *  - maybe add timeout to commands ?
13  *  - blocking version of time functions
14  *  - polling version of i2c commands (including timer that works with
15  *    interrupts off)
16  *  - maybe avoid some data copies with i2c by directly using the smu cmd
17  *    buffer and a lower level internal interface
18  *  - understand SMU -> CPU events and implement reception of them via
19  *    the userland interface
20  */
21
22 #include <linux/types.h>
23 #include <linux/kernel.h>
24 #include <linux/device.h>
25 #include <linux/dmapool.h>
26 #include <linux/bootmem.h>
27 #include <linux/vmalloc.h>
28 #include <linux/highmem.h>
29 #include <linux/jiffies.h>
30 #include <linux/interrupt.h>
31 #include <linux/rtc.h>
32 #include <linux/completion.h>
33 #include <linux/miscdevice.h>
34 #include <linux/delay.h>
35 #include <linux/sysdev.h>
36 #include <linux/poll.h>
37 #include <linux/mutex.h>
38
39 #include <asm/byteorder.h>
40 #include <asm/io.h>
41 #include <asm/prom.h>
42 #include <asm/machdep.h>
43 #include <asm/pmac_feature.h>
44 #include <asm/smu.h>
45 #include <asm/sections.h>
46 #include <asm/abs_addr.h>
47 #include <asm/uaccess.h>
48 #include <asm/of_device.h>
49 #include <asm/of_platform.h>
50
51 #define VERSION "0.7"
52 #define AUTHOR  "(c) 2005 Benjamin Herrenschmidt, IBM Corp."
53
54 #undef DEBUG_SMU
55
56 #ifdef DEBUG_SMU
57 #define DPRINTK(fmt, args...) do { printk(KERN_DEBUG fmt , ##args); } while (0)
58 #else
59 #define DPRINTK(fmt, args...) do { } while (0)
60 #endif
61
62 /*
63  * This is the command buffer passed to the SMU hardware
64  */
65 #define SMU_MAX_DATA    254
66
67 struct smu_cmd_buf {
68         u8 cmd;
69         u8 length;
70         u8 data[SMU_MAX_DATA];
71 };
72
73 struct smu_device {
74         spinlock_t              lock;
75         struct device_node      *of_node;
76         struct of_device        *of_dev;
77         int                     doorbell;       /* doorbell gpio */
78         u32 __iomem             *db_buf;        /* doorbell buffer */
79         struct device_node      *db_node;
80         unsigned int            db_irq;
81         int                     msg;
82         struct device_node      *msg_node;
83         unsigned int            msg_irq;
84         struct smu_cmd_buf      *cmd_buf;       /* command buffer virtual */
85         u32                     cmd_buf_abs;    /* command buffer absolute */
86         struct list_head        cmd_list;
87         struct smu_cmd          *cmd_cur;       /* pending command */
88         int                     broken_nap;
89         struct list_head        cmd_i2c_list;
90         struct smu_i2c_cmd      *cmd_i2c_cur;   /* pending i2c command */
91         struct timer_list       i2c_timer;
92 };
93
94 /*
95  * I don't think there will ever be more than one SMU, so
96  * for now, just hard code that
97  */
98 static struct smu_device        *smu;
99 static DEFINE_MUTEX(smu_part_access);
100 static int smu_irq_inited;
101
102 static void smu_i2c_retry(unsigned long data);
103
104 /*
105  * SMU driver low level stuff
106  */
107
108 static void smu_start_cmd(void)
109 {
110         unsigned long faddr, fend;
111         struct smu_cmd *cmd;
112
113         if (list_empty(&smu->cmd_list))
114                 return;
115
116         /* Fetch first command in queue */
117         cmd = list_entry(smu->cmd_list.next, struct smu_cmd, link);
118         smu->cmd_cur = cmd;
119         list_del(&cmd->link);
120
121         DPRINTK("SMU: starting cmd %x, %d bytes data\n", cmd->cmd,
122                 cmd->data_len);
123         DPRINTK("SMU: data buffer: %02x %02x %02x %02x %02x %02x %02x %02x\n",
124                 ((u8 *)cmd->data_buf)[0], ((u8 *)cmd->data_buf)[1],
125                 ((u8 *)cmd->data_buf)[2], ((u8 *)cmd->data_buf)[3],
126                 ((u8 *)cmd->data_buf)[4], ((u8 *)cmd->data_buf)[5],
127                 ((u8 *)cmd->data_buf)[6], ((u8 *)cmd->data_buf)[7]);
128
129         /* Fill the SMU command buffer */
130         smu->cmd_buf->cmd = cmd->cmd;
131         smu->cmd_buf->length = cmd->data_len;
132         memcpy(smu->cmd_buf->data, cmd->data_buf, cmd->data_len);
133
134         /* Flush command and data to RAM */
135         faddr = (unsigned long)smu->cmd_buf;
136         fend = faddr + smu->cmd_buf->length + 2;
137         flush_inval_dcache_range(faddr, fend);
138
139
140         /* We also disable NAP mode for the duration of the command
141          * on U3 based machines.
142          * This is slightly racy as it can be written back to 1 by a sysctl
143          * but that never happens in practice. There seem to be an issue with
144          * U3 based machines such as the iMac G5 where napping for the
145          * whole duration of the command prevents the SMU from fetching it
146          * from memory. This might be related to the strange i2c based
147          * mechanism the SMU uses to access memory.
148          */
149         if (smu->broken_nap)
150                 powersave_nap = 0;
151
152         /* This isn't exactly a DMA mapping here, I suspect
153          * the SMU is actually communicating with us via i2c to the
154          * northbridge or the CPU to access RAM.
155          */
156         writel(smu->cmd_buf_abs, smu->db_buf);
157
158         /* Ring the SMU doorbell */
159         pmac_do_feature_call(PMAC_FTR_WRITE_GPIO, NULL, smu->doorbell, 4);
160 }
161
162
163 static irqreturn_t smu_db_intr(int irq, void *arg)
164 {
165         unsigned long flags;
166         struct smu_cmd *cmd;
167         void (*done)(struct smu_cmd *cmd, void *misc) = NULL;
168         void *misc = NULL;
169         u8 gpio;
170         int rc = 0;
171
172         /* SMU completed the command, well, we hope, let's make sure
173          * of it
174          */
175         spin_lock_irqsave(&smu->lock, flags);
176
177         gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell);
178         if ((gpio & 7) != 7) {
179                 spin_unlock_irqrestore(&smu->lock, flags);
180                 return IRQ_HANDLED;
181         }
182
183         cmd = smu->cmd_cur;
184         smu->cmd_cur = NULL;
185         if (cmd == NULL)
186                 goto bail;
187
188         if (rc == 0) {
189                 unsigned long faddr;
190                 int reply_len;
191                 u8 ack;
192
193                 /* CPU might have brought back the cache line, so we need
194                  * to flush again before peeking at the SMU response. We
195                  * flush the entire buffer for now as we haven't read the
196                  * reply length (it's only 2 cache lines anyway)
197                  */
198                 faddr = (unsigned long)smu->cmd_buf;
199                 flush_inval_dcache_range(faddr, faddr + 256);
200
201                 /* Now check ack */
202                 ack = (~cmd->cmd) & 0xff;
203                 if (ack != smu->cmd_buf->cmd) {
204                         DPRINTK("SMU: incorrect ack, want %x got %x\n",
205                                 ack, smu->cmd_buf->cmd);
206                         rc = -EIO;
207                 }
208                 reply_len = rc == 0 ? smu->cmd_buf->length : 0;
209                 DPRINTK("SMU: reply len: %d\n", reply_len);
210                 if (reply_len > cmd->reply_len) {
211                         printk(KERN_WARNING "SMU: reply buffer too small,"
212                                "got %d bytes for a %d bytes buffer\n",
213                                reply_len, cmd->reply_len);
214                         reply_len = cmd->reply_len;
215                 }
216                 cmd->reply_len = reply_len;
217                 if (cmd->reply_buf && reply_len)
218                         memcpy(cmd->reply_buf, smu->cmd_buf->data, reply_len);
219         }
220
221         /* Now complete the command. Write status last in order as we lost
222          * ownership of the command structure as soon as it's no longer -1
223          */
224         done = cmd->done;
225         misc = cmd->misc;
226         mb();
227         cmd->status = rc;
228
229         /* Re-enable NAP mode */
230         if (smu->broken_nap)
231                 powersave_nap = 1;
232  bail:
233         /* Start next command if any */
234         smu_start_cmd();
235         spin_unlock_irqrestore(&smu->lock, flags);
236
237         /* Call command completion handler if any */
238         if (done)
239                 done(cmd, misc);
240
241         /* It's an edge interrupt, nothing to do */
242         return IRQ_HANDLED;
243 }
244
245
246 static irqreturn_t smu_msg_intr(int irq, void *arg)
247 {
248         /* I don't quite know what to do with this one, we seem to never
249          * receive it, so I suspect we have to arm it someway in the SMU
250          * to start getting events that way.
251          */
252
253         printk(KERN_INFO "SMU: message interrupt !\n");
254
255         /* It's an edge interrupt, nothing to do */
256         return IRQ_HANDLED;
257 }
258
259
260 /*
261  * Queued command management.
262  *
263  */
264
265 int smu_queue_cmd(struct smu_cmd *cmd)
266 {
267         unsigned long flags;
268
269         if (smu == NULL)
270                 return -ENODEV;
271         if (cmd->data_len > SMU_MAX_DATA ||
272             cmd->reply_len > SMU_MAX_DATA)
273                 return -EINVAL;
274
275         cmd->status = 1;
276         spin_lock_irqsave(&smu->lock, flags);
277         list_add_tail(&cmd->link, &smu->cmd_list);
278         if (smu->cmd_cur == NULL)
279                 smu_start_cmd();
280         spin_unlock_irqrestore(&smu->lock, flags);
281
282         /* Workaround for early calls when irq isn't available */
283         if (!smu_irq_inited || smu->db_irq == NO_IRQ)
284                 smu_spinwait_cmd(cmd);
285
286         return 0;
287 }
288 EXPORT_SYMBOL(smu_queue_cmd);
289
290
291 int smu_queue_simple(struct smu_simple_cmd *scmd, u8 command,
292                      unsigned int data_len,
293                      void (*done)(struct smu_cmd *cmd, void *misc),
294                      void *misc, ...)
295 {
296         struct smu_cmd *cmd = &scmd->cmd;
297         va_list list;
298         int i;
299
300         if (data_len > sizeof(scmd->buffer))
301                 return -EINVAL;
302
303         memset(scmd, 0, sizeof(*scmd));
304         cmd->cmd = command;
305         cmd->data_len = data_len;
306         cmd->data_buf = scmd->buffer;
307         cmd->reply_len = sizeof(scmd->buffer);
308         cmd->reply_buf = scmd->buffer;
309         cmd->done = done;
310         cmd->misc = misc;
311
312         va_start(list, misc);
313         for (i = 0; i < data_len; ++i)
314                 scmd->buffer[i] = (u8)va_arg(list, int);
315         va_end(list);
316
317         return smu_queue_cmd(cmd);
318 }
319 EXPORT_SYMBOL(smu_queue_simple);
320
321
322 void smu_poll(void)
323 {
324         u8 gpio;
325
326         if (smu == NULL)
327                 return;
328
329         gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell);
330         if ((gpio & 7) == 7)
331                 smu_db_intr(smu->db_irq, smu);
332 }
333 EXPORT_SYMBOL(smu_poll);
334
335
336 void smu_done_complete(struct smu_cmd *cmd, void *misc)
337 {
338         struct completion *comp = misc;
339
340         complete(comp);
341 }
342 EXPORT_SYMBOL(smu_done_complete);
343
344
345 void smu_spinwait_cmd(struct smu_cmd *cmd)
346 {
347         while(cmd->status == 1)
348                 smu_poll();
349 }
350 EXPORT_SYMBOL(smu_spinwait_cmd);
351
352
353 /* RTC low level commands */
354 static inline int bcd2hex (int n)
355 {
356         return (((n & 0xf0) >> 4) * 10) + (n & 0xf);
357 }
358
359
360 static inline int hex2bcd (int n)
361 {
362         return ((n / 10) << 4) + (n % 10);
363 }
364
365
366 static inline void smu_fill_set_rtc_cmd(struct smu_cmd_buf *cmd_buf,
367                                         struct rtc_time *time)
368 {
369         cmd_buf->cmd = 0x8e;
370         cmd_buf->length = 8;
371         cmd_buf->data[0] = 0x80;
372         cmd_buf->data[1] = hex2bcd(time->tm_sec);
373         cmd_buf->data[2] = hex2bcd(time->tm_min);
374         cmd_buf->data[3] = hex2bcd(time->tm_hour);
375         cmd_buf->data[4] = time->tm_wday;
376         cmd_buf->data[5] = hex2bcd(time->tm_mday);
377         cmd_buf->data[6] = hex2bcd(time->tm_mon) + 1;
378         cmd_buf->data[7] = hex2bcd(time->tm_year - 100);
379 }
380
381
382 int smu_get_rtc_time(struct rtc_time *time, int spinwait)
383 {
384         struct smu_simple_cmd cmd;
385         int rc;
386
387         if (smu == NULL)
388                 return -ENODEV;
389
390         memset(time, 0, sizeof(struct rtc_time));
391         rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 1, NULL, NULL,
392                               SMU_CMD_RTC_GET_DATETIME);
393         if (rc)
394                 return rc;
395         smu_spinwait_simple(&cmd);
396
397         time->tm_sec = bcd2hex(cmd.buffer[0]);
398         time->tm_min = bcd2hex(cmd.buffer[1]);
399         time->tm_hour = bcd2hex(cmd.buffer[2]);
400         time->tm_wday = bcd2hex(cmd.buffer[3]);
401         time->tm_mday = bcd2hex(cmd.buffer[4]);
402         time->tm_mon = bcd2hex(cmd.buffer[5]) - 1;
403         time->tm_year = bcd2hex(cmd.buffer[6]) + 100;
404
405         return 0;
406 }
407
408
409 int smu_set_rtc_time(struct rtc_time *time, int spinwait)
410 {
411         struct smu_simple_cmd cmd;
412         int rc;
413
414         if (smu == NULL)
415                 return -ENODEV;
416
417         rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 8, NULL, NULL,
418                               SMU_CMD_RTC_SET_DATETIME,
419                               hex2bcd(time->tm_sec),
420                               hex2bcd(time->tm_min),
421                               hex2bcd(time->tm_hour),
422                               time->tm_wday,
423                               hex2bcd(time->tm_mday),
424                               hex2bcd(time->tm_mon) + 1,
425                               hex2bcd(time->tm_year - 100));
426         if (rc)
427                 return rc;
428         smu_spinwait_simple(&cmd);
429
430         return 0;
431 }
432
433
434 void smu_shutdown(void)
435 {
436         struct smu_simple_cmd cmd;
437
438         if (smu == NULL)
439                 return;
440
441         if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 9, NULL, NULL,
442                              'S', 'H', 'U', 'T', 'D', 'O', 'W', 'N', 0))
443                 return;
444         smu_spinwait_simple(&cmd);
445         for (;;)
446                 ;
447 }
448
449
450 void smu_restart(void)
451 {
452         struct smu_simple_cmd cmd;
453
454         if (smu == NULL)
455                 return;
456
457         if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 8, NULL, NULL,
458                              'R', 'E', 'S', 'T', 'A', 'R', 'T', 0))
459                 return;
460         smu_spinwait_simple(&cmd);
461         for (;;)
462                 ;
463 }
464
465
466 int smu_present(void)
467 {
468         return smu != NULL;
469 }
470 EXPORT_SYMBOL(smu_present);
471
472
473 int __init smu_init (void)
474 {
475         struct device_node *np;
476         const u32 *data;
477
478         np = of_find_node_by_type(NULL, "smu");
479         if (np == NULL)
480                 return -ENODEV;
481
482         printk(KERN_INFO "SMU: Driver %s %s\n", VERSION, AUTHOR);
483
484         if (smu_cmdbuf_abs == 0) {
485                 printk(KERN_ERR "SMU: Command buffer not allocated !\n");
486                 of_node_put(np);
487                 return -EINVAL;
488         }
489
490         smu = alloc_bootmem(sizeof(struct smu_device));
491         if (smu == NULL) {
492                 of_node_put(np);
493                 return -ENOMEM;
494         }
495         memset(smu, 0, sizeof(*smu));
496
497         spin_lock_init(&smu->lock);
498         INIT_LIST_HEAD(&smu->cmd_list);
499         INIT_LIST_HEAD(&smu->cmd_i2c_list);
500         smu->of_node = np;
501         smu->db_irq = NO_IRQ;
502         smu->msg_irq = NO_IRQ;
503
504         /* smu_cmdbuf_abs is in the low 2G of RAM, can be converted to a
505          * 32 bits value safely
506          */
507         smu->cmd_buf_abs = (u32)smu_cmdbuf_abs;
508         smu->cmd_buf = (struct smu_cmd_buf *)abs_to_virt(smu_cmdbuf_abs);
509
510         smu->db_node = of_find_node_by_name(NULL, "smu-doorbell");
511         if (smu->db_node == NULL) {
512                 printk(KERN_ERR "SMU: Can't find doorbell GPIO !\n");
513                 goto fail;
514         }
515         data = of_get_property(smu->db_node, "reg", NULL);
516         if (data == NULL) {
517                 of_node_put(smu->db_node);
518                 smu->db_node = NULL;
519                 printk(KERN_ERR "SMU: Can't find doorbell GPIO address !\n");
520                 goto fail;
521         }
522
523         /* Current setup has one doorbell GPIO that does both doorbell
524          * and ack. GPIOs are at 0x50, best would be to find that out
525          * in the device-tree though.
526          */
527         smu->doorbell = *data;
528         if (smu->doorbell < 0x50)
529                 smu->doorbell += 0x50;
530
531         /* Now look for the smu-interrupt GPIO */
532         do {
533                 smu->msg_node = of_find_node_by_name(NULL, "smu-interrupt");
534                 if (smu->msg_node == NULL)
535                         break;
536                 data = of_get_property(smu->msg_node, "reg", NULL);
537                 if (data == NULL) {
538                         of_node_put(smu->msg_node);
539                         smu->msg_node = NULL;
540                         break;
541                 }
542                 smu->msg = *data;
543                 if (smu->msg < 0x50)
544                         smu->msg += 0x50;
545         } while(0);
546
547         /* Doorbell buffer is currently hard-coded, I didn't find a proper
548          * device-tree entry giving the address. Best would probably to use
549          * an offset for K2 base though, but let's do it that way for now.
550          */
551         smu->db_buf = ioremap(0x8000860c, 0x1000);
552         if (smu->db_buf == NULL) {
553                 printk(KERN_ERR "SMU: Can't map doorbell buffer pointer !\n");
554                 goto fail;
555         }
556
557         /* U3 has an issue with NAP mode when issuing SMU commands */
558         smu->broken_nap = pmac_get_uninorth_variant() < 4;
559         if (smu->broken_nap)
560                 printk(KERN_INFO "SMU: using NAP mode workaround\n");
561
562         sys_ctrler = SYS_CTRLER_SMU;
563         return 0;
564
565  fail:
566         smu = NULL;
567         return -ENXIO;
568
569 }
570
571
572 static int smu_late_init(void)
573 {
574         if (!smu)
575                 return 0;
576
577         init_timer(&smu->i2c_timer);
578         smu->i2c_timer.function = smu_i2c_retry;
579         smu->i2c_timer.data = (unsigned long)smu;
580
581         if (smu->db_node) {
582                 smu->db_irq = irq_of_parse_and_map(smu->db_node, 0);
583                 if (smu->db_irq == NO_IRQ)
584                         printk(KERN_ERR "smu: failed to map irq for node %s\n",
585                                smu->db_node->full_name);
586         }
587         if (smu->msg_node) {
588                 smu->msg_irq = irq_of_parse_and_map(smu->msg_node, 0);
589                 if (smu->msg_irq == NO_IRQ)
590                         printk(KERN_ERR "smu: failed to map irq for node %s\n",
591                                smu->msg_node->full_name);
592         }
593
594         /*
595          * Try to request the interrupts
596          */
597
598         if (smu->db_irq != NO_IRQ) {
599                 if (request_irq(smu->db_irq, smu_db_intr,
600                                 IRQF_SHARED, "SMU doorbell", smu) < 0) {
601                         printk(KERN_WARNING "SMU: can't "
602                                "request interrupt %d\n",
603                                smu->db_irq);
604                         smu->db_irq = NO_IRQ;
605                 }
606         }
607
608         if (smu->msg_irq != NO_IRQ) {
609                 if (request_irq(smu->msg_irq, smu_msg_intr,
610                                 IRQF_SHARED, "SMU message", smu) < 0) {
611                         printk(KERN_WARNING "SMU: can't "
612                                "request interrupt %d\n",
613                                smu->msg_irq);
614                         smu->msg_irq = NO_IRQ;
615                 }
616         }
617
618         smu_irq_inited = 1;
619         return 0;
620 }
621 /* This has to be before arch_initcall as the low i2c stuff relies on the
622  * above having been done before we reach arch_initcalls
623  */
624 core_initcall(smu_late_init);
625
626 /*
627  * sysfs visibility
628  */
629
630 static void smu_expose_childs(struct work_struct *unused)
631 {
632         struct device_node *np;
633
634         for (np = NULL; (np = of_get_next_child(smu->of_node, np)) != NULL;)
635                 if (of_device_is_compatible(np, "smu-sensors"))
636                         of_platform_device_create(np, "smu-sensors",
637                                                   &smu->of_dev->dev);
638 }
639
640 static DECLARE_WORK(smu_expose_childs_work, smu_expose_childs);
641
642 static int smu_platform_probe(struct of_device* dev,
643                               const struct of_device_id *match)
644 {
645         if (!smu)
646                 return -ENODEV;
647         smu->of_dev = dev;
648
649         /*
650          * Ok, we are matched, now expose all i2c busses. We have to defer
651          * that unfortunately or it would deadlock inside the device model
652          */
653         schedule_work(&smu_expose_childs_work);
654
655         return 0;
656 }
657
658 static struct of_device_id smu_platform_match[] =
659 {
660         {
661                 .type           = "smu",
662         },
663         {},
664 };
665
666 static struct of_platform_driver smu_of_platform_driver =
667 {
668         .name           = "smu",
669         .match_table    = smu_platform_match,
670         .probe          = smu_platform_probe,
671 };
672
673 static int __init smu_init_sysfs(void)
674 {
675         /*
676          * Due to sysfs bogosity, a sysdev is not a real device, so
677          * we should in fact create both if we want sysdev semantics
678          * for power management.
679          * For now, we don't power manage machines with an SMU chip,
680          * I'm a bit too far from figuring out how that works with those
681          * new chipsets, but that will come back and bite us
682          */
683         of_register_platform_driver(&smu_of_platform_driver);
684         return 0;
685 }
686
687 device_initcall(smu_init_sysfs);
688
689 struct of_device *smu_get_ofdev(void)
690 {
691         if (!smu)
692                 return NULL;
693         return smu->of_dev;
694 }
695
696 EXPORT_SYMBOL_GPL(smu_get_ofdev);
697
698 /*
699  * i2c interface
700  */
701
702 static void smu_i2c_complete_command(struct smu_i2c_cmd *cmd, int fail)
703 {
704         void (*done)(struct smu_i2c_cmd *cmd, void *misc) = cmd->done;
705         void *misc = cmd->misc;
706         unsigned long flags;
707
708         /* Check for read case */
709         if (!fail && cmd->read) {
710                 if (cmd->pdata[0] < 1)
711                         fail = 1;
712                 else
713                         memcpy(cmd->info.data, &cmd->pdata[1],
714                                cmd->info.datalen);
715         }
716
717         DPRINTK("SMU: completing, success: %d\n", !fail);
718
719         /* Update status and mark no pending i2c command with lock
720          * held so nobody comes in while we dequeue an eventual
721          * pending next i2c command
722          */
723         spin_lock_irqsave(&smu->lock, flags);
724         smu->cmd_i2c_cur = NULL;
725         wmb();
726         cmd->status = fail ? -EIO : 0;
727
728         /* Is there another i2c command waiting ? */
729         if (!list_empty(&smu->cmd_i2c_list)) {
730                 struct smu_i2c_cmd *newcmd;
731
732                 /* Fetch it, new current, remove from list */
733                 newcmd = list_entry(smu->cmd_i2c_list.next,
734                                     struct smu_i2c_cmd, link);
735                 smu->cmd_i2c_cur = newcmd;
736                 list_del(&cmd->link);
737
738                 /* Queue with low level smu */
739                 list_add_tail(&cmd->scmd.link, &smu->cmd_list);
740                 if (smu->cmd_cur == NULL)
741                         smu_start_cmd();
742         }
743         spin_unlock_irqrestore(&smu->lock, flags);
744
745         /* Call command completion handler if any */
746         if (done)
747                 done(cmd, misc);
748
749 }
750
751
752 static void smu_i2c_retry(unsigned long data)
753 {
754         struct smu_i2c_cmd      *cmd = smu->cmd_i2c_cur;
755
756         DPRINTK("SMU: i2c failure, requeuing...\n");
757
758         /* requeue command simply by resetting reply_len */
759         cmd->pdata[0] = 0xff;
760         cmd->scmd.reply_len = sizeof(cmd->pdata);
761         smu_queue_cmd(&cmd->scmd);
762 }
763
764
765 static void smu_i2c_low_completion(struct smu_cmd *scmd, void *misc)
766 {
767         struct smu_i2c_cmd      *cmd = misc;
768         int                     fail = 0;
769
770         DPRINTK("SMU: i2c compl. stage=%d status=%x pdata[0]=%x rlen: %x\n",
771                 cmd->stage, scmd->status, cmd->pdata[0], scmd->reply_len);
772
773         /* Check for possible status */
774         if (scmd->status < 0)
775                 fail = 1;
776         else if (cmd->read) {
777                 if (cmd->stage == 0)
778                         fail = cmd->pdata[0] != 0;
779                 else
780                         fail = cmd->pdata[0] >= 0x80;
781         } else {
782                 fail = cmd->pdata[0] != 0;
783         }
784
785         /* Handle failures by requeuing command, after 5ms interval
786          */
787         if (fail && --cmd->retries > 0) {
788                 DPRINTK("SMU: i2c failure, starting timer...\n");
789                 BUG_ON(cmd != smu->cmd_i2c_cur);
790                 if (!smu_irq_inited) {
791                         mdelay(5);
792                         smu_i2c_retry(0);
793                         return;
794                 }
795                 mod_timer(&smu->i2c_timer, jiffies + msecs_to_jiffies(5));
796                 return;
797         }
798
799         /* If failure or stage 1, command is complete */
800         if (fail || cmd->stage != 0) {
801                 smu_i2c_complete_command(cmd, fail);
802                 return;
803         }
804
805         DPRINTK("SMU: going to stage 1\n");
806
807         /* Ok, initial command complete, now poll status */
808         scmd->reply_buf = cmd->pdata;
809         scmd->reply_len = sizeof(cmd->pdata);
810         scmd->data_buf = cmd->pdata;
811         scmd->data_len = 1;
812         cmd->pdata[0] = 0;
813         cmd->stage = 1;
814         cmd->retries = 20;
815         smu_queue_cmd(scmd);
816 }
817
818
819 int smu_queue_i2c(struct smu_i2c_cmd *cmd)
820 {
821         unsigned long flags;
822
823         if (smu == NULL)
824                 return -ENODEV;
825
826         /* Fill most fields of scmd */
827         cmd->scmd.cmd = SMU_CMD_I2C_COMMAND;
828         cmd->scmd.done = smu_i2c_low_completion;
829         cmd->scmd.misc = cmd;
830         cmd->scmd.reply_buf = cmd->pdata;
831         cmd->scmd.reply_len = sizeof(cmd->pdata);
832         cmd->scmd.data_buf = (u8 *)(char *)&cmd->info;
833         cmd->scmd.status = 1;
834         cmd->stage = 0;
835         cmd->pdata[0] = 0xff;
836         cmd->retries = 20;
837         cmd->status = 1;
838
839         /* Check transfer type, sanitize some "info" fields
840          * based on transfer type and do more checking
841          */
842         cmd->info.caddr = cmd->info.devaddr;
843         cmd->read = cmd->info.devaddr & 0x01;
844         switch(cmd->info.type) {
845         case SMU_I2C_TRANSFER_SIMPLE:
846                 memset(&cmd->info.sublen, 0, 4);
847                 break;
848         case SMU_I2C_TRANSFER_COMBINED:
849                 cmd->info.devaddr &= 0xfe;
850         case SMU_I2C_TRANSFER_STDSUB:
851                 if (cmd->info.sublen > 3)
852                         return -EINVAL;
853                 break;
854         default:
855                 return -EINVAL;
856         }
857
858         /* Finish setting up command based on transfer direction
859          */
860         if (cmd->read) {
861                 if (cmd->info.datalen > SMU_I2C_READ_MAX)
862                         return -EINVAL;
863                 memset(cmd->info.data, 0xff, cmd->info.datalen);
864                 cmd->scmd.data_len = 9;
865         } else {
866                 if (cmd->info.datalen > SMU_I2C_WRITE_MAX)
867                         return -EINVAL;
868                 cmd->scmd.data_len = 9 + cmd->info.datalen;
869         }
870
871         DPRINTK("SMU: i2c enqueuing command\n");
872         DPRINTK("SMU:   %s, len=%d bus=%x addr=%x sub0=%x type=%x\n",
873                 cmd->read ? "read" : "write", cmd->info.datalen,
874                 cmd->info.bus, cmd->info.caddr,
875                 cmd->info.subaddr[0], cmd->info.type);
876
877
878         /* Enqueue command in i2c list, and if empty, enqueue also in
879          * main command list
880          */
881         spin_lock_irqsave(&smu->lock, flags);
882         if (smu->cmd_i2c_cur == NULL) {
883                 smu->cmd_i2c_cur = cmd;
884                 list_add_tail(&cmd->scmd.link, &smu->cmd_list);
885                 if (smu->cmd_cur == NULL)
886                         smu_start_cmd();
887         } else
888                 list_add_tail(&cmd->link, &smu->cmd_i2c_list);
889         spin_unlock_irqrestore(&smu->lock, flags);
890
891         return 0;
892 }
893
894 /*
895  * Handling of "partitions"
896  */
897
898 static int smu_read_datablock(u8 *dest, unsigned int addr, unsigned int len)
899 {
900         DECLARE_COMPLETION_ONSTACK(comp);
901         unsigned int chunk;
902         struct smu_cmd cmd;
903         int rc;
904         u8 params[8];
905
906         /* We currently use a chunk size of 0xe. We could check the
907          * SMU firmware version and use bigger sizes though
908          */
909         chunk = 0xe;
910
911         while (len) {
912                 unsigned int clen = min(len, chunk);
913
914                 cmd.cmd = SMU_CMD_MISC_ee_COMMAND;
915                 cmd.data_len = 7;
916                 cmd.data_buf = params;
917                 cmd.reply_len = chunk;
918                 cmd.reply_buf = dest;
919                 cmd.done = smu_done_complete;
920                 cmd.misc = &comp;
921                 params[0] = SMU_CMD_MISC_ee_GET_DATABLOCK_REC;
922                 params[1] = 0x4;
923                 *((u32 *)&params[2]) = addr;
924                 params[6] = clen;
925
926                 rc = smu_queue_cmd(&cmd);
927                 if (rc)
928                         return rc;
929                 wait_for_completion(&comp);
930                 if (cmd.status != 0)
931                         return rc;
932                 if (cmd.reply_len != clen) {
933                         printk(KERN_DEBUG "SMU: short read in "
934                                "smu_read_datablock, got: %d, want: %d\n",
935                                cmd.reply_len, clen);
936                         return -EIO;
937                 }
938                 len -= clen;
939                 addr += clen;
940                 dest += clen;
941         }
942         return 0;
943 }
944
945 static struct smu_sdbp_header *smu_create_sdb_partition(int id)
946 {
947         DECLARE_COMPLETION_ONSTACK(comp);
948         struct smu_simple_cmd cmd;
949         unsigned int addr, len, tlen;
950         struct smu_sdbp_header *hdr;
951         struct property *prop;
952
953         /* First query the partition info */
954         DPRINTK("SMU: Query partition infos ... (irq=%d)\n", smu->db_irq);
955         smu_queue_simple(&cmd, SMU_CMD_PARTITION_COMMAND, 2,
956                          smu_done_complete, &comp,
957                          SMU_CMD_PARTITION_LATEST, id);
958         wait_for_completion(&comp);
959         DPRINTK("SMU: done, status: %d, reply_len: %d\n",
960                 cmd.cmd.status, cmd.cmd.reply_len);
961
962         /* Partition doesn't exist (or other error) */
963         if (cmd.cmd.status != 0 || cmd.cmd.reply_len != 6)
964                 return NULL;
965
966         /* Fetch address and length from reply */
967         addr = *((u16 *)cmd.buffer);
968         len = cmd.buffer[3] << 2;
969         /* Calucluate total length to allocate, including the 17 bytes
970          * for "sdb-partition-XX" that we append at the end of the buffer
971          */
972         tlen = sizeof(struct property) + len + 18;
973
974         prop = kzalloc(tlen, GFP_KERNEL);
975         if (prop == NULL)
976                 return NULL;
977         hdr = (struct smu_sdbp_header *)(prop + 1);
978         prop->name = ((char *)prop) + tlen - 18;
979         sprintf(prop->name, "sdb-partition-%02x", id);
980         prop->length = len;
981         prop->value = hdr;
982         prop->next = NULL;
983
984         /* Read the datablock */
985         if (smu_read_datablock((u8 *)hdr, addr, len)) {
986                 printk(KERN_DEBUG "SMU: datablock read failed while reading "
987                        "partition %02x !\n", id);
988                 goto failure;
989         }
990
991         /* Got it, check a few things and create the property */
992         if (hdr->id != id) {
993                 printk(KERN_DEBUG "SMU: Reading partition %02x and got "
994                        "%02x !\n", id, hdr->id);
995                 goto failure;
996         }
997         if (prom_add_property(smu->of_node, prop)) {
998                 printk(KERN_DEBUG "SMU: Failed creating sdb-partition-%02x "
999                        "property !\n", id);
1000                 goto failure;
1001         }
1002
1003         return hdr;
1004  failure:
1005         kfree(prop);
1006         return NULL;
1007 }
1008
1009 /* Note: Only allowed to return error code in pointers (using ERR_PTR)
1010  * when interruptible is 1
1011  */
1012 const struct smu_sdbp_header *__smu_get_sdb_partition(int id,
1013                 unsigned int *size, int interruptible)
1014 {
1015         char pname[32];
1016         const struct smu_sdbp_header *part;
1017
1018         if (!smu)
1019                 return NULL;
1020
1021         sprintf(pname, "sdb-partition-%02x", id);
1022
1023         DPRINTK("smu_get_sdb_partition(%02x)\n", id);
1024
1025         if (interruptible) {
1026                 int rc;
1027                 rc = mutex_lock_interruptible(&smu_part_access);
1028                 if (rc)
1029                         return ERR_PTR(rc);
1030         } else
1031                 mutex_lock(&smu_part_access);
1032
1033         part = of_get_property(smu->of_node, pname, size);
1034         if (part == NULL) {
1035                 DPRINTK("trying to extract from SMU ...\n");
1036                 part = smu_create_sdb_partition(id);
1037                 if (part != NULL && size)
1038                         *size = part->len << 2;
1039         }
1040         mutex_unlock(&smu_part_access);
1041         return part;
1042 }
1043
1044 const struct smu_sdbp_header *smu_get_sdb_partition(int id, unsigned int *size)
1045 {
1046         return __smu_get_sdb_partition(id, size, 0);
1047 }
1048 EXPORT_SYMBOL(smu_get_sdb_partition);
1049
1050
1051 /*
1052  * Userland driver interface
1053  */
1054
1055
1056 static LIST_HEAD(smu_clist);
1057 static DEFINE_SPINLOCK(smu_clist_lock);
1058
1059 enum smu_file_mode {
1060         smu_file_commands,
1061         smu_file_events,
1062         smu_file_closing
1063 };
1064
1065 struct smu_private
1066 {
1067         struct list_head        list;
1068         enum smu_file_mode      mode;
1069         int                     busy;
1070         struct smu_cmd          cmd;
1071         spinlock_t              lock;
1072         wait_queue_head_t       wait;
1073         u8                      buffer[SMU_MAX_DATA];
1074 };
1075
1076
1077 static int smu_open(struct inode *inode, struct file *file)
1078 {
1079         struct smu_private *pp;
1080         unsigned long flags;
1081
1082         pp = kzalloc(sizeof(struct smu_private), GFP_KERNEL);
1083         if (pp == 0)
1084                 return -ENOMEM;
1085         spin_lock_init(&pp->lock);
1086         pp->mode = smu_file_commands;
1087         init_waitqueue_head(&pp->wait);
1088
1089         spin_lock_irqsave(&smu_clist_lock, flags);
1090         list_add(&pp->list, &smu_clist);
1091         spin_unlock_irqrestore(&smu_clist_lock, flags);
1092         file->private_data = pp;
1093
1094         return 0;
1095 }
1096
1097
1098 static void smu_user_cmd_done(struct smu_cmd *cmd, void *misc)
1099 {
1100         struct smu_private *pp = misc;
1101
1102         wake_up_all(&pp->wait);
1103 }
1104
1105
1106 static ssize_t smu_write(struct file *file, const char __user *buf,
1107                          size_t count, loff_t *ppos)
1108 {
1109         struct smu_private *pp = file->private_data;
1110         unsigned long flags;
1111         struct smu_user_cmd_hdr hdr;
1112         int rc = 0;
1113
1114         if (pp->busy)
1115                 return -EBUSY;
1116         else if (copy_from_user(&hdr, buf, sizeof(hdr)))
1117                 return -EFAULT;
1118         else if (hdr.cmdtype == SMU_CMDTYPE_WANTS_EVENTS) {
1119                 pp->mode = smu_file_events;
1120                 return 0;
1121         } else if (hdr.cmdtype == SMU_CMDTYPE_GET_PARTITION) {
1122                 const struct smu_sdbp_header *part;
1123                 part = __smu_get_sdb_partition(hdr.cmd, NULL, 1);
1124                 if (part == NULL)
1125                         return -EINVAL;
1126                 else if (IS_ERR(part))
1127                         return PTR_ERR(part);
1128                 return 0;
1129         } else if (hdr.cmdtype != SMU_CMDTYPE_SMU)
1130                 return -EINVAL;
1131         else if (pp->mode != smu_file_commands)
1132                 return -EBADFD;
1133         else if (hdr.data_len > SMU_MAX_DATA)
1134                 return -EINVAL;
1135
1136         spin_lock_irqsave(&pp->lock, flags);
1137         if (pp->busy) {
1138                 spin_unlock_irqrestore(&pp->lock, flags);
1139                 return -EBUSY;
1140         }
1141         pp->busy = 1;
1142         pp->cmd.status = 1;
1143         spin_unlock_irqrestore(&pp->lock, flags);
1144
1145         if (copy_from_user(pp->buffer, buf + sizeof(hdr), hdr.data_len)) {
1146                 pp->busy = 0;
1147                 return -EFAULT;
1148         }
1149
1150         pp->cmd.cmd = hdr.cmd;
1151         pp->cmd.data_len = hdr.data_len;
1152         pp->cmd.reply_len = SMU_MAX_DATA;
1153         pp->cmd.data_buf = pp->buffer;
1154         pp->cmd.reply_buf = pp->buffer;
1155         pp->cmd.done = smu_user_cmd_done;
1156         pp->cmd.misc = pp;
1157         rc = smu_queue_cmd(&pp->cmd);
1158         if (rc < 0)
1159                 return rc;
1160         return count;
1161 }
1162
1163
1164 static ssize_t smu_read_command(struct file *file, struct smu_private *pp,
1165                                 char __user *buf, size_t count)
1166 {
1167         DECLARE_WAITQUEUE(wait, current);
1168         struct smu_user_reply_hdr hdr;
1169         unsigned long flags;
1170         int size, rc = 0;
1171
1172         if (!pp->busy)
1173                 return 0;
1174         if (count < sizeof(struct smu_user_reply_hdr))
1175                 return -EOVERFLOW;
1176         spin_lock_irqsave(&pp->lock, flags);
1177         if (pp->cmd.status == 1) {
1178                 if (file->f_flags & O_NONBLOCK)
1179                         return -EAGAIN;
1180                 add_wait_queue(&pp->wait, &wait);
1181                 for (;;) {
1182                         set_current_state(TASK_INTERRUPTIBLE);
1183                         rc = 0;
1184                         if (pp->cmd.status != 1)
1185                                 break;
1186                         rc = -ERESTARTSYS;
1187                         if (signal_pending(current))
1188                                 break;
1189                         spin_unlock_irqrestore(&pp->lock, flags);
1190                         schedule();
1191                         spin_lock_irqsave(&pp->lock, flags);
1192                 }
1193                 set_current_state(TASK_RUNNING);
1194                 remove_wait_queue(&pp->wait, &wait);
1195         }
1196         spin_unlock_irqrestore(&pp->lock, flags);
1197         if (rc)
1198                 return rc;
1199         if (pp->cmd.status != 0)
1200                 pp->cmd.reply_len = 0;
1201         size = sizeof(hdr) + pp->cmd.reply_len;
1202         if (count < size)
1203                 size = count;
1204         rc = size;
1205         hdr.status = pp->cmd.status;
1206         hdr.reply_len = pp->cmd.reply_len;
1207         if (copy_to_user(buf, &hdr, sizeof(hdr)))
1208                 return -EFAULT;
1209         size -= sizeof(hdr);
1210         if (size && copy_to_user(buf + sizeof(hdr), pp->buffer, size))
1211                 return -EFAULT;
1212         pp->busy = 0;
1213
1214         return rc;
1215 }
1216
1217
1218 static ssize_t smu_read_events(struct file *file, struct smu_private *pp,
1219                                char __user *buf, size_t count)
1220 {
1221         /* Not implemented */
1222         msleep_interruptible(1000);
1223         return 0;
1224 }
1225
1226
1227 static ssize_t smu_read(struct file *file, char __user *buf,
1228                         size_t count, loff_t *ppos)
1229 {
1230         struct smu_private *pp = file->private_data;
1231
1232         if (pp->mode == smu_file_commands)
1233                 return smu_read_command(file, pp, buf, count);
1234         if (pp->mode == smu_file_events)
1235                 return smu_read_events(file, pp, buf, count);
1236
1237         return -EBADFD;
1238 }
1239
1240 static unsigned int smu_fpoll(struct file *file, poll_table *wait)
1241 {
1242         struct smu_private *pp = file->private_data;
1243         unsigned int mask = 0;
1244         unsigned long flags;
1245
1246         if (pp == 0)
1247                 return 0;
1248
1249         if (pp->mode == smu_file_commands) {
1250                 poll_wait(file, &pp->wait, wait);
1251
1252                 spin_lock_irqsave(&pp->lock, flags);
1253                 if (pp->busy && pp->cmd.status != 1)
1254                         mask |= POLLIN;
1255                 spin_unlock_irqrestore(&pp->lock, flags);
1256         } if (pp->mode == smu_file_events) {
1257                 /* Not yet implemented */
1258         }
1259         return mask;
1260 }
1261
1262 static int smu_release(struct inode *inode, struct file *file)
1263 {
1264         struct smu_private *pp = file->private_data;
1265         unsigned long flags;
1266         unsigned int busy;
1267
1268         if (pp == 0)
1269                 return 0;
1270
1271         file->private_data = NULL;
1272
1273         /* Mark file as closing to avoid races with new request */
1274         spin_lock_irqsave(&pp->lock, flags);
1275         pp->mode = smu_file_closing;
1276         busy = pp->busy;
1277
1278         /* Wait for any pending request to complete */
1279         if (busy && pp->cmd.status == 1) {
1280                 DECLARE_WAITQUEUE(wait, current);
1281
1282                 add_wait_queue(&pp->wait, &wait);
1283                 for (;;) {
1284                         set_current_state(TASK_UNINTERRUPTIBLE);
1285                         if (pp->cmd.status != 1)
1286                                 break;
1287                         spin_unlock_irqrestore(&pp->lock, flags);
1288                         schedule();
1289                         spin_lock_irqsave(&pp->lock, flags);
1290                 }
1291                 set_current_state(TASK_RUNNING);
1292                 remove_wait_queue(&pp->wait, &wait);
1293         }
1294         spin_unlock_irqrestore(&pp->lock, flags);
1295
1296         spin_lock_irqsave(&smu_clist_lock, flags);
1297         list_del(&pp->list);
1298         spin_unlock_irqrestore(&smu_clist_lock, flags);
1299         kfree(pp);
1300
1301         return 0;
1302 }
1303
1304
1305 static const struct file_operations smu_device_fops = {
1306         .llseek         = no_llseek,
1307         .read           = smu_read,
1308         .write          = smu_write,
1309         .poll           = smu_fpoll,
1310         .open           = smu_open,
1311         .release        = smu_release,
1312 };
1313
1314 static struct miscdevice pmu_device = {
1315         MISC_DYNAMIC_MINOR, "smu", &smu_device_fops
1316 };
1317
1318 static int smu_device_init(void)
1319 {
1320         if (!smu)
1321                 return -ENODEV;
1322         if (misc_register(&pmu_device) < 0)
1323                 printk(KERN_ERR "via-pmu: cannot register misc device.\n");
1324         return 0;
1325 }
1326 device_initcall(smu_device_init);