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