ade25b3fbb35bd5057b17a623c801ef76a762a5c
[linux-3.10.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
50 #define VERSION "0.7"
51 #define AUTHOR  "(c) 2005 Benjamin Herrenschmidt, IBM Corp."
52
53 #undef DEBUG_SMU
54
55 #ifdef DEBUG_SMU
56 #define DPRINTK(fmt, args...) do { printk(KERN_DEBUG fmt , ##args); } while (0)
57 #else
58 #define DPRINTK(fmt, args...) do { } while (0)
59 #endif
60
61 /*
62  * This is the command buffer passed to the SMU hardware
63  */
64 #define SMU_MAX_DATA    254
65
66 struct smu_cmd_buf {
67         u8 cmd;
68         u8 length;
69         u8 data[SMU_MAX_DATA];
70 };
71
72 struct smu_device {
73         spinlock_t              lock;
74         struct device_node      *of_node;
75         struct of_device        *of_dev;
76         int                     doorbell;       /* doorbell gpio */
77         u32 __iomem             *db_buf;        /* doorbell buffer */
78         struct device_node      *db_node;
79         unsigned int            db_irq;
80         int                     msg;
81         struct device_node      *msg_node;
82         unsigned int            msg_irq;
83         struct smu_cmd_buf      *cmd_buf;       /* command buffer virtual */
84         u32                     cmd_buf_abs;    /* command buffer absolute */
85         struct list_head        cmd_list;
86         struct smu_cmd          *cmd_cur;       /* pending command */
87         struct list_head        cmd_i2c_list;
88         struct smu_i2c_cmd      *cmd_i2c_cur;   /* pending i2c command */
89         struct timer_list       i2c_timer;
90 };
91
92 /*
93  * I don't think there will ever be more than one SMU, so
94  * for now, just hard code that
95  */
96 static struct smu_device        *smu;
97 static DEFINE_MUTEX(smu_part_access);
98 static int smu_irq_inited;
99
100 static void smu_i2c_retry(unsigned long data);
101
102 /*
103  * SMU driver low level stuff
104  */
105
106 static void smu_start_cmd(void)
107 {
108         unsigned long faddr, fend;
109         struct smu_cmd *cmd;
110
111         if (list_empty(&smu->cmd_list))
112                 return;
113
114         /* Fetch first command in queue */
115         cmd = list_entry(smu->cmd_list.next, struct smu_cmd, link);
116         smu->cmd_cur = cmd;
117         list_del(&cmd->link);
118
119         DPRINTK("SMU: starting cmd %x, %d bytes data\n", cmd->cmd,
120                 cmd->data_len);
121         DPRINTK("SMU: data buffer: %02x %02x %02x %02x %02x %02x %02x %02x\n",
122                 ((u8 *)cmd->data_buf)[0], ((u8 *)cmd->data_buf)[1],
123                 ((u8 *)cmd->data_buf)[2], ((u8 *)cmd->data_buf)[3],
124                 ((u8 *)cmd->data_buf)[4], ((u8 *)cmd->data_buf)[5],
125                 ((u8 *)cmd->data_buf)[6], ((u8 *)cmd->data_buf)[7]);
126
127         /* Fill the SMU command buffer */
128         smu->cmd_buf->cmd = cmd->cmd;
129         smu->cmd_buf->length = cmd->data_len;
130         memcpy(smu->cmd_buf->data, cmd->data_buf, cmd->data_len);
131
132         /* Flush command and data to RAM */
133         faddr = (unsigned long)smu->cmd_buf;
134         fend = faddr + smu->cmd_buf->length + 2;
135         flush_inval_dcache_range(faddr, fend);
136
137         /* This isn't exactly a DMA mapping here, I suspect
138          * the SMU is actually communicating with us via i2c to the
139          * northbridge or the CPU to access RAM.
140          */
141         writel(smu->cmd_buf_abs, smu->db_buf);
142
143         /* Ring the SMU doorbell */
144         pmac_do_feature_call(PMAC_FTR_WRITE_GPIO, NULL, smu->doorbell, 4);
145 }
146
147
148 static irqreturn_t smu_db_intr(int irq, void *arg)
149 {
150         unsigned long flags;
151         struct smu_cmd *cmd;
152         void (*done)(struct smu_cmd *cmd, void *misc) = NULL;
153         void *misc = NULL;
154         u8 gpio;
155         int rc = 0;
156
157         /* SMU completed the command, well, we hope, let's make sure
158          * of it
159          */
160         spin_lock_irqsave(&smu->lock, flags);
161
162         gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell);
163         if ((gpio & 7) != 7) {
164                 spin_unlock_irqrestore(&smu->lock, flags);
165                 return IRQ_HANDLED;
166         }
167
168         cmd = smu->cmd_cur;
169         smu->cmd_cur = NULL;
170         if (cmd == NULL)
171                 goto bail;
172
173         if (rc == 0) {
174                 unsigned long faddr;
175                 int reply_len;
176                 u8 ack;
177
178                 /* CPU might have brought back the cache line, so we need
179                  * to flush again before peeking at the SMU response. We
180                  * flush the entire buffer for now as we haven't read the
181                  * reply lenght (it's only 2 cache lines anyway)
182                  */
183                 faddr = (unsigned long)smu->cmd_buf;
184                 flush_inval_dcache_range(faddr, faddr + 256);
185
186                 /* Now check ack */
187                 ack = (~cmd->cmd) & 0xff;
188                 if (ack != smu->cmd_buf->cmd) {
189                         DPRINTK("SMU: incorrect ack, want %x got %x\n",
190                                 ack, smu->cmd_buf->cmd);
191                         rc = -EIO;
192                 }
193                 reply_len = rc == 0 ? smu->cmd_buf->length : 0;
194                 DPRINTK("SMU: reply len: %d\n", reply_len);
195                 if (reply_len > cmd->reply_len) {
196                         printk(KERN_WARNING "SMU: reply buffer too small,"
197                                "got %d bytes for a %d bytes buffer\n",
198                                reply_len, cmd->reply_len);
199                         reply_len = cmd->reply_len;
200                 }
201                 cmd->reply_len = reply_len;
202                 if (cmd->reply_buf && reply_len)
203                         memcpy(cmd->reply_buf, smu->cmd_buf->data, reply_len);
204         }
205
206         /* Now complete the command. Write status last in order as we lost
207          * ownership of the command structure as soon as it's no longer -1
208          */
209         done = cmd->done;
210         misc = cmd->misc;
211         mb();
212         cmd->status = rc;
213  bail:
214         /* Start next command if any */
215         smu_start_cmd();
216         spin_unlock_irqrestore(&smu->lock, flags);
217
218         /* Call command completion handler if any */
219         if (done)
220                 done(cmd, misc);
221
222         /* It's an edge interrupt, nothing to do */
223         return IRQ_HANDLED;
224 }
225
226
227 static irqreturn_t smu_msg_intr(int irq, void *arg)
228 {
229         /* I don't quite know what to do with this one, we seem to never
230          * receive it, so I suspect we have to arm it someway in the SMU
231          * to start getting events that way.
232          */
233
234         printk(KERN_INFO "SMU: message interrupt !\n");
235
236         /* It's an edge interrupt, nothing to do */
237         return IRQ_HANDLED;
238 }
239
240
241 /*
242  * Queued command management.
243  *
244  */
245
246 int smu_queue_cmd(struct smu_cmd *cmd)
247 {
248         unsigned long flags;
249
250         if (smu == NULL)
251                 return -ENODEV;
252         if (cmd->data_len > SMU_MAX_DATA ||
253             cmd->reply_len > SMU_MAX_DATA)
254                 return -EINVAL;
255
256         cmd->status = 1;
257         spin_lock_irqsave(&smu->lock, flags);
258         list_add_tail(&cmd->link, &smu->cmd_list);
259         if (smu->cmd_cur == NULL)
260                 smu_start_cmd();
261         spin_unlock_irqrestore(&smu->lock, flags);
262
263         /* Workaround for early calls when irq isn't available */
264         if (!smu_irq_inited || smu->db_irq == NO_IRQ)
265                 smu_spinwait_cmd(cmd);
266
267         return 0;
268 }
269 EXPORT_SYMBOL(smu_queue_cmd);
270
271
272 int smu_queue_simple(struct smu_simple_cmd *scmd, u8 command,
273                      unsigned int data_len,
274                      void (*done)(struct smu_cmd *cmd, void *misc),
275                      void *misc, ...)
276 {
277         struct smu_cmd *cmd = &scmd->cmd;
278         va_list list;
279         int i;
280
281         if (data_len > sizeof(scmd->buffer))
282                 return -EINVAL;
283
284         memset(scmd, 0, sizeof(*scmd));
285         cmd->cmd = command;
286         cmd->data_len = data_len;
287         cmd->data_buf = scmd->buffer;
288         cmd->reply_len = sizeof(scmd->buffer);
289         cmd->reply_buf = scmd->buffer;
290         cmd->done = done;
291         cmd->misc = misc;
292
293         va_start(list, misc);
294         for (i = 0; i < data_len; ++i)
295                 scmd->buffer[i] = (u8)va_arg(list, int);
296         va_end(list);
297
298         return smu_queue_cmd(cmd);
299 }
300 EXPORT_SYMBOL(smu_queue_simple);
301
302
303 void smu_poll(void)
304 {
305         u8 gpio;
306
307         if (smu == NULL)
308                 return;
309
310         gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell);
311         if ((gpio & 7) == 7)
312                 smu_db_intr(smu->db_irq, smu);
313 }
314 EXPORT_SYMBOL(smu_poll);
315
316
317 void smu_done_complete(struct smu_cmd *cmd, void *misc)
318 {
319         struct completion *comp = misc;
320
321         complete(comp);
322 }
323 EXPORT_SYMBOL(smu_done_complete);
324
325
326 void smu_spinwait_cmd(struct smu_cmd *cmd)
327 {
328         while(cmd->status == 1)
329                 smu_poll();
330 }
331 EXPORT_SYMBOL(smu_spinwait_cmd);
332
333
334 /* RTC low level commands */
335 static inline int bcd2hex (int n)
336 {
337         return (((n & 0xf0) >> 4) * 10) + (n & 0xf);
338 }
339
340
341 static inline int hex2bcd (int n)
342 {
343         return ((n / 10) << 4) + (n % 10);
344 }
345
346
347 static inline void smu_fill_set_rtc_cmd(struct smu_cmd_buf *cmd_buf,
348                                         struct rtc_time *time)
349 {
350         cmd_buf->cmd = 0x8e;
351         cmd_buf->length = 8;
352         cmd_buf->data[0] = 0x80;
353         cmd_buf->data[1] = hex2bcd(time->tm_sec);
354         cmd_buf->data[2] = hex2bcd(time->tm_min);
355         cmd_buf->data[3] = hex2bcd(time->tm_hour);
356         cmd_buf->data[4] = time->tm_wday;
357         cmd_buf->data[5] = hex2bcd(time->tm_mday);
358         cmd_buf->data[6] = hex2bcd(time->tm_mon) + 1;
359         cmd_buf->data[7] = hex2bcd(time->tm_year - 100);
360 }
361
362
363 int smu_get_rtc_time(struct rtc_time *time, int spinwait)
364 {
365         struct smu_simple_cmd cmd;
366         int rc;
367
368         if (smu == NULL)
369                 return -ENODEV;
370
371         memset(time, 0, sizeof(struct rtc_time));
372         rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 1, NULL, NULL,
373                               SMU_CMD_RTC_GET_DATETIME);
374         if (rc)
375                 return rc;
376         smu_spinwait_simple(&cmd);
377
378         time->tm_sec = bcd2hex(cmd.buffer[0]);
379         time->tm_min = bcd2hex(cmd.buffer[1]);
380         time->tm_hour = bcd2hex(cmd.buffer[2]);
381         time->tm_wday = bcd2hex(cmd.buffer[3]);
382         time->tm_mday = bcd2hex(cmd.buffer[4]);
383         time->tm_mon = bcd2hex(cmd.buffer[5]) - 1;
384         time->tm_year = bcd2hex(cmd.buffer[6]) + 100;
385
386         return 0;
387 }
388
389
390 int smu_set_rtc_time(struct rtc_time *time, int spinwait)
391 {
392         struct smu_simple_cmd cmd;
393         int rc;
394
395         if (smu == NULL)
396                 return -ENODEV;
397
398         rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 8, NULL, NULL,
399                               SMU_CMD_RTC_SET_DATETIME,
400                               hex2bcd(time->tm_sec),
401                               hex2bcd(time->tm_min),
402                               hex2bcd(time->tm_hour),
403                               time->tm_wday,
404                               hex2bcd(time->tm_mday),
405                               hex2bcd(time->tm_mon) + 1,
406                               hex2bcd(time->tm_year - 100));
407         if (rc)
408                 return rc;
409         smu_spinwait_simple(&cmd);
410
411         return 0;
412 }
413
414
415 void smu_shutdown(void)
416 {
417         struct smu_simple_cmd cmd;
418
419         if (smu == NULL)
420                 return;
421
422         if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 9, NULL, NULL,
423                              'S', 'H', 'U', 'T', 'D', 'O', 'W', 'N', 0))
424                 return;
425         smu_spinwait_simple(&cmd);
426         for (;;)
427                 ;
428 }
429
430
431 void smu_restart(void)
432 {
433         struct smu_simple_cmd cmd;
434
435         if (smu == NULL)
436                 return;
437
438         if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 8, NULL, NULL,
439                              'R', 'E', 'S', 'T', 'A', 'R', 'T', 0))
440                 return;
441         smu_spinwait_simple(&cmd);
442         for (;;)
443                 ;
444 }
445
446
447 int smu_present(void)
448 {
449         return smu != NULL;
450 }
451 EXPORT_SYMBOL(smu_present);
452
453
454 int __init smu_init (void)
455 {
456         struct device_node *np;
457         const u32 *data;
458
459         np = of_find_node_by_type(NULL, "smu");
460         if (np == NULL)
461                 return -ENODEV;
462
463         printk(KERN_INFO "SMU driver %s %s\n", VERSION, AUTHOR);
464
465         if (smu_cmdbuf_abs == 0) {
466                 printk(KERN_ERR "SMU: Command buffer not allocated !\n");
467                 return -EINVAL;
468         }
469
470         smu = alloc_bootmem(sizeof(struct smu_device));
471         if (smu == NULL)
472                 return -ENOMEM;
473         memset(smu, 0, sizeof(*smu));
474
475         spin_lock_init(&smu->lock);
476         INIT_LIST_HEAD(&smu->cmd_list);
477         INIT_LIST_HEAD(&smu->cmd_i2c_list);
478         smu->of_node = np;
479         smu->db_irq = NO_IRQ;
480         smu->msg_irq = NO_IRQ;
481
482         /* smu_cmdbuf_abs is in the low 2G of RAM, can be converted to a
483          * 32 bits value safely
484          */
485         smu->cmd_buf_abs = (u32)smu_cmdbuf_abs;
486         smu->cmd_buf = (struct smu_cmd_buf *)abs_to_virt(smu_cmdbuf_abs);
487
488         smu->db_node = of_find_node_by_name(NULL, "smu-doorbell");
489         if (smu->db_node == NULL) {
490                 printk(KERN_ERR "SMU: Can't find doorbell GPIO !\n");
491                 goto fail;
492         }
493         data = get_property(smu->db_node, "reg", NULL);
494         if (data == NULL) {
495                 of_node_put(smu->db_node);
496                 smu->db_node = NULL;
497                 printk(KERN_ERR "SMU: Can't find doorbell GPIO address !\n");
498                 goto fail;
499         }
500
501         /* Current setup has one doorbell GPIO that does both doorbell
502          * and ack. GPIOs are at 0x50, best would be to find that out
503          * in the device-tree though.
504          */
505         smu->doorbell = *data;
506         if (smu->doorbell < 0x50)
507                 smu->doorbell += 0x50;
508
509         /* Now look for the smu-interrupt GPIO */
510         do {
511                 smu->msg_node = of_find_node_by_name(NULL, "smu-interrupt");
512                 if (smu->msg_node == NULL)
513                         break;
514                 data = get_property(smu->msg_node, "reg", NULL);
515                 if (data == NULL) {
516                         of_node_put(smu->msg_node);
517                         smu->msg_node = NULL;
518                         break;
519                 }
520                 smu->msg = *data;
521                 if (smu->msg < 0x50)
522                         smu->msg += 0x50;
523         } while(0);
524
525         /* Doorbell buffer is currently hard-coded, I didn't find a proper
526          * device-tree entry giving the address. Best would probably to use
527          * an offset for K2 base though, but let's do it that way for now.
528          */
529         smu->db_buf = ioremap(0x8000860c, 0x1000);
530         if (smu->db_buf == NULL) {
531                 printk(KERN_ERR "SMU: Can't map doorbell buffer pointer !\n");
532                 goto fail;
533         }
534
535         sys_ctrler = SYS_CTRLER_SMU;
536         return 0;
537
538  fail:
539         smu = NULL;
540         return -ENXIO;
541
542 }
543
544
545 static int smu_late_init(void)
546 {
547         if (!smu)
548                 return 0;
549
550         init_timer(&smu->i2c_timer);
551         smu->i2c_timer.function = smu_i2c_retry;
552         smu->i2c_timer.data = (unsigned long)smu;
553
554         if (smu->db_node) {
555                 smu->db_irq = irq_of_parse_and_map(smu->db_node, 0);
556                 if (smu->db_irq == NO_IRQ)
557                         printk(KERN_ERR "smu: failed to map irq for node %s\n",
558                                smu->db_node->full_name);
559         }
560         if (smu->msg_node) {
561                 smu->msg_irq = irq_of_parse_and_map(smu->msg_node, 0);
562                 if (smu->msg_irq == NO_IRQ)
563                         printk(KERN_ERR "smu: failed to map irq for node %s\n",
564                                smu->msg_node->full_name);
565         }
566
567         /*
568          * Try to request the interrupts
569          */
570
571         if (smu->db_irq != NO_IRQ) {
572                 if (request_irq(smu->db_irq, smu_db_intr,
573                                 IRQF_SHARED, "SMU doorbell", smu) < 0) {
574                         printk(KERN_WARNING "SMU: can't "
575                                "request interrupt %d\n",
576                                smu->db_irq);
577                         smu->db_irq = NO_IRQ;
578                 }
579         }
580
581         if (smu->msg_irq != NO_IRQ) {
582                 if (request_irq(smu->msg_irq, smu_msg_intr,
583                                 IRQF_SHARED, "SMU message", smu) < 0) {
584                         printk(KERN_WARNING "SMU: can't "
585                                "request interrupt %d\n",
586                                smu->msg_irq);
587                         smu->msg_irq = NO_IRQ;
588                 }
589         }
590
591         smu_irq_inited = 1;
592         return 0;
593 }
594 /* This has to be before arch_initcall as the low i2c stuff relies on the
595  * above having been done before we reach arch_initcalls
596  */
597 core_initcall(smu_late_init);
598
599 /*
600  * sysfs visibility
601  */
602
603 static void smu_expose_childs(void *unused)
604 {
605         struct device_node *np;
606
607         for (np = NULL; (np = of_get_next_child(smu->of_node, np)) != NULL;)
608                 if (device_is_compatible(np, "smu-sensors"))
609                         of_platform_device_create(np, "smu-sensors",
610                                                   &smu->of_dev->dev);
611 }
612
613 static DECLARE_WORK(smu_expose_childs_work, smu_expose_childs, NULL);
614
615 static int smu_platform_probe(struct of_device* dev,
616                               const struct of_device_id *match)
617 {
618         if (!smu)
619                 return -ENODEV;
620         smu->of_dev = dev;
621
622         /*
623          * Ok, we are matched, now expose all i2c busses. We have to defer
624          * that unfortunately or it would deadlock inside the device model
625          */
626         schedule_work(&smu_expose_childs_work);
627
628         return 0;
629 }
630
631 static struct of_device_id smu_platform_match[] =
632 {
633         {
634                 .type           = "smu",
635         },
636         {},
637 };
638
639 static struct of_platform_driver smu_of_platform_driver =
640 {
641         .name           = "smu",
642         .match_table    = smu_platform_match,
643         .probe          = smu_platform_probe,
644 };
645
646 static int __init smu_init_sysfs(void)
647 {
648         /*
649          * Due to sysfs bogosity, a sysdev is not a real device, so
650          * we should in fact create both if we want sysdev semantics
651          * for power management.
652          * For now, we don't power manage machines with an SMU chip,
653          * I'm a bit too far from figuring out how that works with those
654          * new chipsets, but that will come back and bite us
655          */
656         of_register_driver(&smu_of_platform_driver);
657         return 0;
658 }
659
660 device_initcall(smu_init_sysfs);
661
662 struct of_device *smu_get_ofdev(void)
663 {
664         if (!smu)
665                 return NULL;
666         return smu->of_dev;
667 }
668
669 EXPORT_SYMBOL_GPL(smu_get_ofdev);
670
671 /*
672  * i2c interface
673  */
674
675 static void smu_i2c_complete_command(struct smu_i2c_cmd *cmd, int fail)
676 {
677         void (*done)(struct smu_i2c_cmd *cmd, void *misc) = cmd->done;
678         void *misc = cmd->misc;
679         unsigned long flags;
680
681         /* Check for read case */
682         if (!fail && cmd->read) {
683                 if (cmd->pdata[0] < 1)
684                         fail = 1;
685                 else
686                         memcpy(cmd->info.data, &cmd->pdata[1],
687                                cmd->info.datalen);
688         }
689
690         DPRINTK("SMU: completing, success: %d\n", !fail);
691
692         /* Update status and mark no pending i2c command with lock
693          * held so nobody comes in while we dequeue an eventual
694          * pending next i2c command
695          */
696         spin_lock_irqsave(&smu->lock, flags);
697         smu->cmd_i2c_cur = NULL;
698         wmb();
699         cmd->status = fail ? -EIO : 0;
700
701         /* Is there another i2c command waiting ? */
702         if (!list_empty(&smu->cmd_i2c_list)) {
703                 struct smu_i2c_cmd *newcmd;
704
705                 /* Fetch it, new current, remove from list */
706                 newcmd = list_entry(smu->cmd_i2c_list.next,
707                                     struct smu_i2c_cmd, link);
708                 smu->cmd_i2c_cur = newcmd;
709                 list_del(&cmd->link);
710
711                 /* Queue with low level smu */
712                 list_add_tail(&cmd->scmd.link, &smu->cmd_list);
713                 if (smu->cmd_cur == NULL)
714                         smu_start_cmd();
715         }
716         spin_unlock_irqrestore(&smu->lock, flags);
717
718         /* Call command completion handler if any */
719         if (done)
720                 done(cmd, misc);
721
722 }
723
724
725 static void smu_i2c_retry(unsigned long data)
726 {
727         struct smu_i2c_cmd      *cmd = smu->cmd_i2c_cur;
728
729         DPRINTK("SMU: i2c failure, requeuing...\n");
730
731         /* requeue command simply by resetting reply_len */
732         cmd->pdata[0] = 0xff;
733         cmd->scmd.reply_len = sizeof(cmd->pdata);
734         smu_queue_cmd(&cmd->scmd);
735 }
736
737
738 static void smu_i2c_low_completion(struct smu_cmd *scmd, void *misc)
739 {
740         struct smu_i2c_cmd      *cmd = misc;
741         int                     fail = 0;
742
743         DPRINTK("SMU: i2c compl. stage=%d status=%x pdata[0]=%x rlen: %x\n",
744                 cmd->stage, scmd->status, cmd->pdata[0], scmd->reply_len);
745
746         /* Check for possible status */
747         if (scmd->status < 0)
748                 fail = 1;
749         else if (cmd->read) {
750                 if (cmd->stage == 0)
751                         fail = cmd->pdata[0] != 0;
752                 else
753                         fail = cmd->pdata[0] >= 0x80;
754         } else {
755                 fail = cmd->pdata[0] != 0;
756         }
757
758         /* Handle failures by requeuing command, after 5ms interval
759          */
760         if (fail && --cmd->retries > 0) {
761                 DPRINTK("SMU: i2c failure, starting timer...\n");
762                 BUG_ON(cmd != smu->cmd_i2c_cur);
763                 if (!smu_irq_inited) {
764                         mdelay(5);
765                         smu_i2c_retry(0);
766                         return;
767                 }
768                 mod_timer(&smu->i2c_timer, jiffies + msecs_to_jiffies(5));
769                 return;
770         }
771
772         /* If failure or stage 1, command is complete */
773         if (fail || cmd->stage != 0) {
774                 smu_i2c_complete_command(cmd, fail);
775                 return;
776         }
777
778         DPRINTK("SMU: going to stage 1\n");
779
780         /* Ok, initial command complete, now poll status */
781         scmd->reply_buf = cmd->pdata;
782         scmd->reply_len = sizeof(cmd->pdata);
783         scmd->data_buf = cmd->pdata;
784         scmd->data_len = 1;
785         cmd->pdata[0] = 0;
786         cmd->stage = 1;
787         cmd->retries = 20;
788         smu_queue_cmd(scmd);
789 }
790
791
792 int smu_queue_i2c(struct smu_i2c_cmd *cmd)
793 {
794         unsigned long flags;
795
796         if (smu == NULL)
797                 return -ENODEV;
798
799         /* Fill most fields of scmd */
800         cmd->scmd.cmd = SMU_CMD_I2C_COMMAND;
801         cmd->scmd.done = smu_i2c_low_completion;
802         cmd->scmd.misc = cmd;
803         cmd->scmd.reply_buf = cmd->pdata;
804         cmd->scmd.reply_len = sizeof(cmd->pdata);
805         cmd->scmd.data_buf = (u8 *)(char *)&cmd->info;
806         cmd->scmd.status = 1;
807         cmd->stage = 0;
808         cmd->pdata[0] = 0xff;
809         cmd->retries = 20;
810         cmd->status = 1;
811
812         /* Check transfer type, sanitize some "info" fields
813          * based on transfer type and do more checking
814          */
815         cmd->info.caddr = cmd->info.devaddr;
816         cmd->read = cmd->info.devaddr & 0x01;
817         switch(cmd->info.type) {
818         case SMU_I2C_TRANSFER_SIMPLE:
819                 memset(&cmd->info.sublen, 0, 4);
820                 break;
821         case SMU_I2C_TRANSFER_COMBINED:
822                 cmd->info.devaddr &= 0xfe;
823         case SMU_I2C_TRANSFER_STDSUB:
824                 if (cmd->info.sublen > 3)
825                         return -EINVAL;
826                 break;
827         default:
828                 return -EINVAL;
829         }
830
831         /* Finish setting up command based on transfer direction
832          */
833         if (cmd->read) {
834                 if (cmd->info.datalen > SMU_I2C_READ_MAX)
835                         return -EINVAL;
836                 memset(cmd->info.data, 0xff, cmd->info.datalen);
837                 cmd->scmd.data_len = 9;
838         } else {
839                 if (cmd->info.datalen > SMU_I2C_WRITE_MAX)
840                         return -EINVAL;
841                 cmd->scmd.data_len = 9 + cmd->info.datalen;
842         }
843
844         DPRINTK("SMU: i2c enqueuing command\n");
845         DPRINTK("SMU:   %s, len=%d bus=%x addr=%x sub0=%x type=%x\n",
846                 cmd->read ? "read" : "write", cmd->info.datalen,
847                 cmd->info.bus, cmd->info.caddr,
848                 cmd->info.subaddr[0], cmd->info.type);
849
850
851         /* Enqueue command in i2c list, and if empty, enqueue also in
852          * main command list
853          */
854         spin_lock_irqsave(&smu->lock, flags);
855         if (smu->cmd_i2c_cur == NULL) {
856                 smu->cmd_i2c_cur = cmd;
857                 list_add_tail(&cmd->scmd.link, &smu->cmd_list);
858                 if (smu->cmd_cur == NULL)
859                         smu_start_cmd();
860         } else
861                 list_add_tail(&cmd->link, &smu->cmd_i2c_list);
862         spin_unlock_irqrestore(&smu->lock, flags);
863
864         return 0;
865 }
866
867 /*
868  * Handling of "partitions"
869  */
870
871 static int smu_read_datablock(u8 *dest, unsigned int addr, unsigned int len)
872 {
873         DECLARE_COMPLETION_ONSTACK(comp);
874         unsigned int chunk;
875         struct smu_cmd cmd;
876         int rc;
877         u8 params[8];
878
879         /* We currently use a chunk size of 0xe. We could check the
880          * SMU firmware version and use bigger sizes though
881          */
882         chunk = 0xe;
883
884         while (len) {
885                 unsigned int clen = min(len, chunk);
886
887                 cmd.cmd = SMU_CMD_MISC_ee_COMMAND;
888                 cmd.data_len = 7;
889                 cmd.data_buf = params;
890                 cmd.reply_len = chunk;
891                 cmd.reply_buf = dest;
892                 cmd.done = smu_done_complete;
893                 cmd.misc = &comp;
894                 params[0] = SMU_CMD_MISC_ee_GET_DATABLOCK_REC;
895                 params[1] = 0x4;
896                 *((u32 *)&params[2]) = addr;
897                 params[6] = clen;
898
899                 rc = smu_queue_cmd(&cmd);
900                 if (rc)
901                         return rc;
902                 wait_for_completion(&comp);
903                 if (cmd.status != 0)
904                         return rc;
905                 if (cmd.reply_len != clen) {
906                         printk(KERN_DEBUG "SMU: short read in "
907                                "smu_read_datablock, got: %d, want: %d\n",
908                                cmd.reply_len, clen);
909                         return -EIO;
910                 }
911                 len -= clen;
912                 addr += clen;
913                 dest += clen;
914         }
915         return 0;
916 }
917
918 static struct smu_sdbp_header *smu_create_sdb_partition(int id)
919 {
920         DECLARE_COMPLETION_ONSTACK(comp);
921         struct smu_simple_cmd cmd;
922         unsigned int addr, len, tlen;
923         struct smu_sdbp_header *hdr;
924         struct property *prop;
925
926         /* First query the partition info */
927         DPRINTK("SMU: Query partition infos ... (irq=%d)\n", smu->db_irq);
928         smu_queue_simple(&cmd, SMU_CMD_PARTITION_COMMAND, 2,
929                          smu_done_complete, &comp,
930                          SMU_CMD_PARTITION_LATEST, id);
931         wait_for_completion(&comp);
932         DPRINTK("SMU: done, status: %d, reply_len: %d\n",
933                 cmd.cmd.status, cmd.cmd.reply_len);
934
935         /* Partition doesn't exist (or other error) */
936         if (cmd.cmd.status != 0 || cmd.cmd.reply_len != 6)
937                 return NULL;
938
939         /* Fetch address and length from reply */
940         addr = *((u16 *)cmd.buffer);
941         len = cmd.buffer[3] << 2;
942         /* Calucluate total length to allocate, including the 17 bytes
943          * for "sdb-partition-XX" that we append at the end of the buffer
944          */
945         tlen = sizeof(struct property) + len + 18;
946
947         prop = kcalloc(tlen, 1, GFP_KERNEL);
948         if (prop == NULL)
949                 return NULL;
950         hdr = (struct smu_sdbp_header *)(prop + 1);
951         prop->name = ((char *)prop) + tlen - 18;
952         sprintf(prop->name, "sdb-partition-%02x", id);
953         prop->length = len;
954         prop->value = (unsigned char *)hdr;
955         prop->next = NULL;
956
957         /* Read the datablock */
958         if (smu_read_datablock((u8 *)hdr, addr, len)) {
959                 printk(KERN_DEBUG "SMU: datablock read failed while reading "
960                        "partition %02x !\n", id);
961                 goto failure;
962         }
963
964         /* Got it, check a few things and create the property */
965         if (hdr->id != id) {
966                 printk(KERN_DEBUG "SMU: Reading partition %02x and got "
967                        "%02x !\n", id, hdr->id);
968                 goto failure;
969         }
970         if (prom_add_property(smu->of_node, prop)) {
971                 printk(KERN_DEBUG "SMU: Failed creating sdb-partition-%02x "
972                        "property !\n", id);
973                 goto failure;
974         }
975
976         return hdr;
977  failure:
978         kfree(prop);
979         return NULL;
980 }
981
982 /* Note: Only allowed to return error code in pointers (using ERR_PTR)
983  * when interruptible is 1
984  */
985 const struct smu_sdbp_header *__smu_get_sdb_partition(int id,
986                 unsigned int *size, int interruptible)
987 {
988         char pname[32];
989         const struct smu_sdbp_header *part;
990
991         if (!smu)
992                 return NULL;
993
994         sprintf(pname, "sdb-partition-%02x", id);
995
996         DPRINTK("smu_get_sdb_partition(%02x)\n", id);
997
998         if (interruptible) {
999                 int rc;
1000                 rc = mutex_lock_interruptible(&smu_part_access);
1001                 if (rc)
1002                         return ERR_PTR(rc);
1003         } else
1004                 mutex_lock(&smu_part_access);
1005
1006         part = get_property(smu->of_node, pname, size);
1007         if (part == NULL) {
1008                 DPRINTK("trying to extract from SMU ...\n");
1009                 part = smu_create_sdb_partition(id);
1010                 if (part != NULL && size)
1011                         *size = part->len << 2;
1012         }
1013         mutex_unlock(&smu_part_access);
1014         return part;
1015 }
1016
1017 const struct smu_sdbp_header *smu_get_sdb_partition(int id, unsigned int *size)
1018 {
1019         return __smu_get_sdb_partition(id, size, 0);
1020 }
1021 EXPORT_SYMBOL(smu_get_sdb_partition);
1022
1023
1024 /*
1025  * Userland driver interface
1026  */
1027
1028
1029 static LIST_HEAD(smu_clist);
1030 static DEFINE_SPINLOCK(smu_clist_lock);
1031
1032 enum smu_file_mode {
1033         smu_file_commands,
1034         smu_file_events,
1035         smu_file_closing
1036 };
1037
1038 struct smu_private
1039 {
1040         struct list_head        list;
1041         enum smu_file_mode      mode;
1042         int                     busy;
1043         struct smu_cmd          cmd;
1044         spinlock_t              lock;
1045         wait_queue_head_t       wait;
1046         u8                      buffer[SMU_MAX_DATA];
1047 };
1048
1049
1050 static int smu_open(struct inode *inode, struct file *file)
1051 {
1052         struct smu_private *pp;
1053         unsigned long flags;
1054
1055         pp = kmalloc(sizeof(struct smu_private), GFP_KERNEL);
1056         if (pp == 0)
1057                 return -ENOMEM;
1058         memset(pp, 0, sizeof(struct smu_private));
1059         spin_lock_init(&pp->lock);
1060         pp->mode = smu_file_commands;
1061         init_waitqueue_head(&pp->wait);
1062
1063         spin_lock_irqsave(&smu_clist_lock, flags);
1064         list_add(&pp->list, &smu_clist);
1065         spin_unlock_irqrestore(&smu_clist_lock, flags);
1066         file->private_data = pp;
1067
1068         return 0;
1069 }
1070
1071
1072 static void smu_user_cmd_done(struct smu_cmd *cmd, void *misc)
1073 {
1074         struct smu_private *pp = misc;
1075
1076         wake_up_all(&pp->wait);
1077 }
1078
1079
1080 static ssize_t smu_write(struct file *file, const char __user *buf,
1081                          size_t count, loff_t *ppos)
1082 {
1083         struct smu_private *pp = file->private_data;
1084         unsigned long flags;
1085         struct smu_user_cmd_hdr hdr;
1086         int rc = 0;
1087
1088         if (pp->busy)
1089                 return -EBUSY;
1090         else if (copy_from_user(&hdr, buf, sizeof(hdr)))
1091                 return -EFAULT;
1092         else if (hdr.cmdtype == SMU_CMDTYPE_WANTS_EVENTS) {
1093                 pp->mode = smu_file_events;
1094                 return 0;
1095         } else if (hdr.cmdtype == SMU_CMDTYPE_GET_PARTITION) {
1096                 const struct smu_sdbp_header *part;
1097                 part = __smu_get_sdb_partition(hdr.cmd, NULL, 1);
1098                 if (part == NULL)
1099                         return -EINVAL;
1100                 else if (IS_ERR(part))
1101                         return PTR_ERR(part);
1102                 return 0;
1103         } else if (hdr.cmdtype != SMU_CMDTYPE_SMU)
1104                 return -EINVAL;
1105         else if (pp->mode != smu_file_commands)
1106                 return -EBADFD;
1107         else if (hdr.data_len > SMU_MAX_DATA)
1108                 return -EINVAL;
1109
1110         spin_lock_irqsave(&pp->lock, flags);
1111         if (pp->busy) {
1112                 spin_unlock_irqrestore(&pp->lock, flags);
1113                 return -EBUSY;
1114         }
1115         pp->busy = 1;
1116         pp->cmd.status = 1;
1117         spin_unlock_irqrestore(&pp->lock, flags);
1118
1119         if (copy_from_user(pp->buffer, buf + sizeof(hdr), hdr.data_len)) {
1120                 pp->busy = 0;
1121                 return -EFAULT;
1122         }
1123
1124         pp->cmd.cmd = hdr.cmd;
1125         pp->cmd.data_len = hdr.data_len;
1126         pp->cmd.reply_len = SMU_MAX_DATA;
1127         pp->cmd.data_buf = pp->buffer;
1128         pp->cmd.reply_buf = pp->buffer;
1129         pp->cmd.done = smu_user_cmd_done;
1130         pp->cmd.misc = pp;
1131         rc = smu_queue_cmd(&pp->cmd);
1132         if (rc < 0)
1133                 return rc;
1134         return count;
1135 }
1136
1137
1138 static ssize_t smu_read_command(struct file *file, struct smu_private *pp,
1139                                 char __user *buf, size_t count)
1140 {
1141         DECLARE_WAITQUEUE(wait, current);
1142         struct smu_user_reply_hdr hdr;
1143         unsigned long flags;
1144         int size, rc = 0;
1145
1146         if (!pp->busy)
1147                 return 0;
1148         if (count < sizeof(struct smu_user_reply_hdr))
1149                 return -EOVERFLOW;
1150         spin_lock_irqsave(&pp->lock, flags);
1151         if (pp->cmd.status == 1) {
1152                 if (file->f_flags & O_NONBLOCK)
1153                         return -EAGAIN;
1154                 add_wait_queue(&pp->wait, &wait);
1155                 for (;;) {
1156                         set_current_state(TASK_INTERRUPTIBLE);
1157                         rc = 0;
1158                         if (pp->cmd.status != 1)
1159                                 break;
1160                         rc = -ERESTARTSYS;
1161                         if (signal_pending(current))
1162                                 break;
1163                         spin_unlock_irqrestore(&pp->lock, flags);
1164                         schedule();
1165                         spin_lock_irqsave(&pp->lock, flags);
1166                 }
1167                 set_current_state(TASK_RUNNING);
1168                 remove_wait_queue(&pp->wait, &wait);
1169         }
1170         spin_unlock_irqrestore(&pp->lock, flags);
1171         if (rc)
1172                 return rc;
1173         if (pp->cmd.status != 0)
1174                 pp->cmd.reply_len = 0;
1175         size = sizeof(hdr) + pp->cmd.reply_len;
1176         if (count < size)
1177                 size = count;
1178         rc = size;
1179         hdr.status = pp->cmd.status;
1180         hdr.reply_len = pp->cmd.reply_len;
1181         if (copy_to_user(buf, &hdr, sizeof(hdr)))
1182                 return -EFAULT;
1183         size -= sizeof(hdr);
1184         if (size && copy_to_user(buf + sizeof(hdr), pp->buffer, size))
1185                 return -EFAULT;
1186         pp->busy = 0;
1187
1188         return rc;
1189 }
1190
1191
1192 static ssize_t smu_read_events(struct file *file, struct smu_private *pp,
1193                                char __user *buf, size_t count)
1194 {
1195         /* Not implemented */
1196         msleep_interruptible(1000);
1197         return 0;
1198 }
1199
1200
1201 static ssize_t smu_read(struct file *file, char __user *buf,
1202                         size_t count, loff_t *ppos)
1203 {
1204         struct smu_private *pp = file->private_data;
1205
1206         if (pp->mode == smu_file_commands)
1207                 return smu_read_command(file, pp, buf, count);
1208         if (pp->mode == smu_file_events)
1209                 return smu_read_events(file, pp, buf, count);
1210
1211         return -EBADFD;
1212 }
1213
1214 static unsigned int smu_fpoll(struct file *file, poll_table *wait)
1215 {
1216         struct smu_private *pp = file->private_data;
1217         unsigned int mask = 0;
1218         unsigned long flags;
1219
1220         if (pp == 0)
1221                 return 0;
1222
1223         if (pp->mode == smu_file_commands) {
1224                 poll_wait(file, &pp->wait, wait);
1225
1226                 spin_lock_irqsave(&pp->lock, flags);
1227                 if (pp->busy && pp->cmd.status != 1)
1228                         mask |= POLLIN;
1229                 spin_unlock_irqrestore(&pp->lock, flags);
1230         } if (pp->mode == smu_file_events) {
1231                 /* Not yet implemented */
1232         }
1233         return mask;
1234 }
1235
1236 static int smu_release(struct inode *inode, struct file *file)
1237 {
1238         struct smu_private *pp = file->private_data;
1239         unsigned long flags;
1240         unsigned int busy;
1241
1242         if (pp == 0)
1243                 return 0;
1244
1245         file->private_data = NULL;
1246
1247         /* Mark file as closing to avoid races with new request */
1248         spin_lock_irqsave(&pp->lock, flags);
1249         pp->mode = smu_file_closing;
1250         busy = pp->busy;
1251
1252         /* Wait for any pending request to complete */
1253         if (busy && pp->cmd.status == 1) {
1254                 DECLARE_WAITQUEUE(wait, current);
1255
1256                 add_wait_queue(&pp->wait, &wait);
1257                 for (;;) {
1258                         set_current_state(TASK_UNINTERRUPTIBLE);
1259                         if (pp->cmd.status != 1)
1260                                 break;
1261                         spin_lock_irqsave(&pp->lock, flags);
1262                         schedule();
1263                         spin_unlock_irqrestore(&pp->lock, flags);
1264                 }
1265                 set_current_state(TASK_RUNNING);
1266                 remove_wait_queue(&pp->wait, &wait);
1267         }
1268         spin_unlock_irqrestore(&pp->lock, flags);
1269
1270         spin_lock_irqsave(&smu_clist_lock, flags);
1271         list_del(&pp->list);
1272         spin_unlock_irqrestore(&smu_clist_lock, flags);
1273         kfree(pp);
1274
1275         return 0;
1276 }
1277
1278
1279 static struct file_operations smu_device_fops = {
1280         .llseek         = no_llseek,
1281         .read           = smu_read,
1282         .write          = smu_write,
1283         .poll           = smu_fpoll,
1284         .open           = smu_open,
1285         .release        = smu_release,
1286 };
1287
1288 static struct miscdevice pmu_device = {
1289         MISC_DYNAMIC_MINOR, "smu", &smu_device_fops
1290 };
1291
1292 static int smu_device_init(void)
1293 {
1294         if (!smu)
1295                 return -ENODEV;
1296         if (misc_register(&pmu_device) < 0)
1297                 printk(KERN_ERR "via-pmu: cannot register misc device.\n");
1298         return 0;
1299 }
1300 device_initcall(smu_device_init);