2 * PowerMac G5 SMU driver
4 * Copyright 2004 J. Mayer <l_indien@magic.fr>
5 * Copyright 2005 Benjamin Herrenschmidt, IBM Corp.
7 * Released under the term of the GNU GPL v2.
12 * - maybe add timeout to commands ?
13 * - blocking version of time functions
14 * - polling version of i2c commands (including timer that works with
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
22 #include <linux/config.h>
23 #include <linux/types.h>
24 #include <linux/kernel.h>
25 #include <linux/device.h>
26 #include <linux/dmapool.h>
27 #include <linux/bootmem.h>
28 #include <linux/vmalloc.h>
29 #include <linux/highmem.h>
30 #include <linux/jiffies.h>
31 #include <linux/interrupt.h>
32 #include <linux/rtc.h>
33 #include <linux/completion.h>
34 #include <linux/miscdevice.h>
35 #include <linux/delay.h>
36 #include <linux/sysdev.h>
37 #include <linux/poll.h>
39 #include <asm/byteorder.h>
42 #include <asm/machdep.h>
43 #include <asm/pmac_feature.h>
45 #include <asm/sections.h>
46 #include <asm/abs_addr.h>
47 #include <asm/uaccess.h>
48 #include <asm/of_device.h>
51 #define AUTHOR "(c) 2005 Benjamin Herrenschmidt, IBM Corp."
56 #define DPRINTK(fmt, args...) do { printk(KERN_DEBUG fmt , ##args); } while (0)
58 #define DPRINTK(fmt, args...) do { } while (0)
62 * This is the command buffer passed to the SMU hardware
64 #define SMU_MAX_DATA 254
69 u8 data[SMU_MAX_DATA];
74 struct device_node *of_node;
75 struct of_device *of_dev;
76 int doorbell; /* doorbell gpio */
77 u32 __iomem *db_buf; /* doorbell buffer */
81 struct smu_cmd_buf *cmd_buf; /* command buffer virtual */
82 u32 cmd_buf_abs; /* command buffer absolute */
83 struct list_head cmd_list;
84 struct smu_cmd *cmd_cur; /* pending command */
85 struct list_head cmd_i2c_list;
86 struct smu_i2c_cmd *cmd_i2c_cur; /* pending i2c command */
87 struct timer_list i2c_timer;
91 * I don't think there will ever be more than one SMU, so
92 * for now, just hard code that
94 static struct smu_device *smu;
98 * SMU driver low level stuff
101 static void smu_start_cmd(void)
103 unsigned long faddr, fend;
106 if (list_empty(&smu->cmd_list))
109 /* Fetch first command in queue */
110 cmd = list_entry(smu->cmd_list.next, struct smu_cmd, link);
112 list_del(&cmd->link);
114 DPRINTK("SMU: starting cmd %x, %d bytes data\n", cmd->cmd,
116 DPRINTK("SMU: data buffer: %02x %02x %02x %02x ...\n",
117 ((u8 *)cmd->data_buf)[0], ((u8 *)cmd->data_buf)[1],
118 ((u8 *)cmd->data_buf)[2], ((u8 *)cmd->data_buf)[3]);
120 /* Fill the SMU command buffer */
121 smu->cmd_buf->cmd = cmd->cmd;
122 smu->cmd_buf->length = cmd->data_len;
123 memcpy(smu->cmd_buf->data, cmd->data_buf, cmd->data_len);
125 /* Flush command and data to RAM */
126 faddr = (unsigned long)smu->cmd_buf;
127 fend = faddr + smu->cmd_buf->length + 2;
128 flush_inval_dcache_range(faddr, fend);
130 /* This isn't exactly a DMA mapping here, I suspect
131 * the SMU is actually communicating with us via i2c to the
132 * northbridge or the CPU to access RAM.
134 writel(smu->cmd_buf_abs, smu->db_buf);
136 /* Ring the SMU doorbell */
137 pmac_do_feature_call(PMAC_FTR_WRITE_GPIO, NULL, smu->doorbell, 4);
141 static irqreturn_t smu_db_intr(int irq, void *arg, struct pt_regs *regs)
145 void (*done)(struct smu_cmd *cmd, void *misc) = NULL;
150 /* SMU completed the command, well, we hope, let's make sure
153 spin_lock_irqsave(&smu->lock, flags);
155 gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell);
169 /* CPU might have brought back the cache line, so we need
170 * to flush again before peeking at the SMU response. We
171 * flush the entire buffer for now as we haven't read the
172 * reply lenght (it's only 2 cache lines anyway)
174 faddr = (unsigned long)smu->cmd_buf;
175 flush_inval_dcache_range(faddr, faddr + 256);
178 ack = (~cmd->cmd) & 0xff;
179 if (ack != smu->cmd_buf->cmd) {
180 DPRINTK("SMU: incorrect ack, want %x got %x\n",
181 ack, smu->cmd_buf->cmd);
184 reply_len = rc == 0 ? smu->cmd_buf->length : 0;
185 DPRINTK("SMU: reply len: %d\n", reply_len);
186 if (reply_len > cmd->reply_len) {
187 printk(KERN_WARNING "SMU: reply buffer too small,"
188 "got %d bytes for a %d bytes buffer\n",
189 reply_len, cmd->reply_len);
190 reply_len = cmd->reply_len;
192 cmd->reply_len = reply_len;
193 if (cmd->reply_buf && reply_len)
194 memcpy(cmd->reply_buf, smu->cmd_buf->data, reply_len);
197 /* Now complete the command. Write status last in order as we lost
198 * ownership of the command structure as soon as it's no longer -1
205 /* Start next command if any */
207 spin_unlock_irqrestore(&smu->lock, flags);
209 /* Call command completion handler if any */
213 /* It's an edge interrupt, nothing to do */
218 static irqreturn_t smu_msg_intr(int irq, void *arg, struct pt_regs *regs)
220 /* I don't quite know what to do with this one, we seem to never
221 * receive it, so I suspect we have to arm it someway in the SMU
222 * to start getting events that way.
225 printk(KERN_INFO "SMU: message interrupt !\n");
227 /* It's an edge interrupt, nothing to do */
233 * Queued command management.
237 int smu_queue_cmd(struct smu_cmd *cmd)
243 if (cmd->data_len > SMU_MAX_DATA ||
244 cmd->reply_len > SMU_MAX_DATA)
248 spin_lock_irqsave(&smu->lock, flags);
249 list_add_tail(&cmd->link, &smu->cmd_list);
250 if (smu->cmd_cur == NULL)
252 spin_unlock_irqrestore(&smu->lock, flags);
256 EXPORT_SYMBOL(smu_queue_cmd);
259 int smu_queue_simple(struct smu_simple_cmd *scmd, u8 command,
260 unsigned int data_len,
261 void (*done)(struct smu_cmd *cmd, void *misc),
264 struct smu_cmd *cmd = &scmd->cmd;
268 if (data_len > sizeof(scmd->buffer))
271 memset(scmd, 0, sizeof(*scmd));
273 cmd->data_len = data_len;
274 cmd->data_buf = scmd->buffer;
275 cmd->reply_len = sizeof(scmd->buffer);
276 cmd->reply_buf = scmd->buffer;
280 va_start(list, misc);
281 for (i = 0; i < data_len; ++i)
282 scmd->buffer[i] = (u8)va_arg(list, int);
285 return smu_queue_cmd(cmd);
287 EXPORT_SYMBOL(smu_queue_simple);
297 gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell);
299 smu_db_intr(smu->db_irq, smu, NULL);
301 EXPORT_SYMBOL(smu_poll);
304 void smu_done_complete(struct smu_cmd *cmd, void *misc)
306 struct completion *comp = misc;
310 EXPORT_SYMBOL(smu_done_complete);
313 void smu_spinwait_cmd(struct smu_cmd *cmd)
315 while(cmd->status == 1)
318 EXPORT_SYMBOL(smu_spinwait_cmd);
321 /* RTC low level commands */
322 static inline int bcd2hex (int n)
324 return (((n & 0xf0) >> 4) * 10) + (n & 0xf);
328 static inline int hex2bcd (int n)
330 return ((n / 10) << 4) + (n % 10);
334 static inline void smu_fill_set_rtc_cmd(struct smu_cmd_buf *cmd_buf,
335 struct rtc_time *time)
339 cmd_buf->data[0] = 0x80;
340 cmd_buf->data[1] = hex2bcd(time->tm_sec);
341 cmd_buf->data[2] = hex2bcd(time->tm_min);
342 cmd_buf->data[3] = hex2bcd(time->tm_hour);
343 cmd_buf->data[4] = time->tm_wday;
344 cmd_buf->data[5] = hex2bcd(time->tm_mday);
345 cmd_buf->data[6] = hex2bcd(time->tm_mon) + 1;
346 cmd_buf->data[7] = hex2bcd(time->tm_year - 100);
350 int smu_get_rtc_time(struct rtc_time *time, int spinwait)
352 struct smu_simple_cmd cmd;
358 memset(time, 0, sizeof(struct rtc_time));
359 rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 1, NULL, NULL,
360 SMU_CMD_RTC_GET_DATETIME);
363 smu_spinwait_simple(&cmd);
365 time->tm_sec = bcd2hex(cmd.buffer[0]);
366 time->tm_min = bcd2hex(cmd.buffer[1]);
367 time->tm_hour = bcd2hex(cmd.buffer[2]);
368 time->tm_wday = bcd2hex(cmd.buffer[3]);
369 time->tm_mday = bcd2hex(cmd.buffer[4]);
370 time->tm_mon = bcd2hex(cmd.buffer[5]) - 1;
371 time->tm_year = bcd2hex(cmd.buffer[6]) + 100;
377 int smu_set_rtc_time(struct rtc_time *time, int spinwait)
379 struct smu_simple_cmd cmd;
385 rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 8, NULL, NULL,
386 SMU_CMD_RTC_SET_DATETIME,
387 hex2bcd(time->tm_sec),
388 hex2bcd(time->tm_min),
389 hex2bcd(time->tm_hour),
391 hex2bcd(time->tm_mday),
392 hex2bcd(time->tm_mon) + 1,
393 hex2bcd(time->tm_year - 100));
396 smu_spinwait_simple(&cmd);
402 void smu_shutdown(void)
404 struct smu_simple_cmd cmd;
409 if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 9, NULL, NULL,
410 'S', 'H', 'U', 'T', 'D', 'O', 'W', 'N', 0))
412 smu_spinwait_simple(&cmd);
418 void smu_restart(void)
420 struct smu_simple_cmd cmd;
425 if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 8, NULL, NULL,
426 'R', 'E', 'S', 'T', 'A', 'R', 'T', 0))
428 smu_spinwait_simple(&cmd);
434 int smu_present(void)
438 EXPORT_SYMBOL(smu_present);
443 struct device_node *np;
446 np = of_find_node_by_type(NULL, "smu");
450 printk(KERN_INFO "SMU driver %s %s\n", VERSION, AUTHOR);
452 if (smu_cmdbuf_abs == 0) {
453 printk(KERN_ERR "SMU: Command buffer not allocated !\n");
457 smu = alloc_bootmem(sizeof(struct smu_device));
460 memset(smu, 0, sizeof(*smu));
462 spin_lock_init(&smu->lock);
463 INIT_LIST_HEAD(&smu->cmd_list);
464 INIT_LIST_HEAD(&smu->cmd_i2c_list);
466 smu->db_irq = NO_IRQ;
467 smu->msg_irq = NO_IRQ;
468 init_timer(&smu->i2c_timer);
470 /* smu_cmdbuf_abs is in the low 2G of RAM, can be converted to a
471 * 32 bits value safely
473 smu->cmd_buf_abs = (u32)smu_cmdbuf_abs;
474 smu->cmd_buf = (struct smu_cmd_buf *)abs_to_virt(smu_cmdbuf_abs);
476 np = of_find_node_by_name(NULL, "smu-doorbell");
478 printk(KERN_ERR "SMU: Can't find doorbell GPIO !\n");
481 data = (u32 *)get_property(np, "reg", NULL);
484 printk(KERN_ERR "SMU: Can't find doorbell GPIO address !\n");
488 /* Current setup has one doorbell GPIO that does both doorbell
489 * and ack. GPIOs are at 0x50, best would be to find that out
490 * in the device-tree though.
492 smu->doorbell = *data;
493 if (smu->doorbell < 0x50)
494 smu->doorbell += 0x50;
496 smu->db_irq = np->intrs[0].line;
500 /* Now look for the smu-interrupt GPIO */
502 np = of_find_node_by_name(NULL, "smu-interrupt");
505 data = (u32 *)get_property(np, "reg", NULL);
514 smu->msg_irq = np->intrs[0].line;
518 /* Doorbell buffer is currently hard-coded, I didn't find a proper
519 * device-tree entry giving the address. Best would probably to use
520 * an offset for K2 base though, but let's do it that way for now.
522 smu->db_buf = ioremap(0x8000860c, 0x1000);
523 if (smu->db_buf == NULL) {
524 printk(KERN_ERR "SMU: Can't map doorbell buffer pointer !\n");
528 sys_ctrler = SYS_CTRLER_SMU;
538 static int smu_late_init(void)
544 * Try to request the interrupts
547 if (smu->db_irq != NO_IRQ) {
548 if (request_irq(smu->db_irq, smu_db_intr,
549 SA_SHIRQ, "SMU doorbell", smu) < 0) {
550 printk(KERN_WARNING "SMU: can't "
551 "request interrupt %d\n",
553 smu->db_irq = NO_IRQ;
557 if (smu->msg_irq != NO_IRQ) {
558 if (request_irq(smu->msg_irq, smu_msg_intr,
559 SA_SHIRQ, "SMU message", smu) < 0) {
560 printk(KERN_WARNING "SMU: can't "
561 "request interrupt %d\n",
563 smu->msg_irq = NO_IRQ;
569 arch_initcall(smu_late_init);
575 static void smu_expose_childs(void *unused)
577 struct device_node *np;
579 for (np = NULL; (np = of_get_next_child(smu->of_node, np)) != NULL;) {
580 if (device_is_compatible(np, "smu-i2c")) {
582 u32 *reg = (u32 *)get_property(np, "reg", NULL);
586 sprintf(name, "smu-i2c-%02x", *reg);
587 of_platform_device_create(np, name, &smu->of_dev->dev);
593 static DECLARE_WORK(smu_expose_childs_work, smu_expose_childs, NULL);
595 static int smu_platform_probe(struct of_device* dev,
596 const struct of_device_id *match)
603 * Ok, we are matched, now expose all i2c busses. We have to defer
604 * that unfortunately or it would deadlock inside the device model
606 schedule_work(&smu_expose_childs_work);
611 static struct of_device_id smu_platform_match[] =
619 static struct of_platform_driver smu_of_platform_driver =
622 .match_table = smu_platform_match,
623 .probe = smu_platform_probe,
626 static int __init smu_init_sysfs(void)
631 * Due to sysfs bogosity, a sysdev is not a real device, so
632 * we should in fact create both if we want sysdev semantics
633 * for power management.
634 * For now, we don't power manage machines with an SMU chip,
635 * I'm a bit too far from figuring out how that works with those
636 * new chipsets, but that will come back and bite us
638 rc = of_register_driver(&smu_of_platform_driver);
642 device_initcall(smu_init_sysfs);
644 struct of_device *smu_get_ofdev(void)
651 EXPORT_SYMBOL_GPL(smu_get_ofdev);
657 static void smu_i2c_complete_command(struct smu_i2c_cmd *cmd, int fail)
659 void (*done)(struct smu_i2c_cmd *cmd, void *misc) = cmd->done;
660 void *misc = cmd->misc;
663 /* Check for read case */
664 if (!fail && cmd->read) {
665 if (cmd->pdata[0] < 1)
668 memcpy(cmd->info.data, &cmd->pdata[1],
672 DPRINTK("SMU: completing, success: %d\n", !fail);
674 /* Update status and mark no pending i2c command with lock
675 * held so nobody comes in while we dequeue an eventual
676 * pending next i2c command
678 spin_lock_irqsave(&smu->lock, flags);
679 smu->cmd_i2c_cur = NULL;
681 cmd->status = fail ? -EIO : 0;
683 /* Is there another i2c command waiting ? */
684 if (!list_empty(&smu->cmd_i2c_list)) {
685 struct smu_i2c_cmd *newcmd;
687 /* Fetch it, new current, remove from list */
688 newcmd = list_entry(smu->cmd_i2c_list.next,
689 struct smu_i2c_cmd, link);
690 smu->cmd_i2c_cur = newcmd;
691 list_del(&cmd->link);
693 /* Queue with low level smu */
694 list_add_tail(&cmd->scmd.link, &smu->cmd_list);
695 if (smu->cmd_cur == NULL)
698 spin_unlock_irqrestore(&smu->lock, flags);
700 /* Call command completion handler if any */
707 static void smu_i2c_retry(unsigned long data)
709 struct smu_i2c_cmd *cmd = (struct smu_i2c_cmd *)data;
711 DPRINTK("SMU: i2c failure, requeuing...\n");
713 /* requeue command simply by resetting reply_len */
714 cmd->pdata[0] = 0xff;
715 cmd->scmd.reply_len = 0x10;
716 smu_queue_cmd(&cmd->scmd);
720 static void smu_i2c_low_completion(struct smu_cmd *scmd, void *misc)
722 struct smu_i2c_cmd *cmd = misc;
725 DPRINTK("SMU: i2c compl. stage=%d status=%x pdata[0]=%x rlen: %x\n",
726 cmd->stage, scmd->status, cmd->pdata[0], scmd->reply_len);
728 /* Check for possible status */
729 if (scmd->status < 0)
731 else if (cmd->read) {
733 fail = cmd->pdata[0] != 0;
735 fail = cmd->pdata[0] >= 0x80;
737 fail = cmd->pdata[0] != 0;
740 /* Handle failures by requeuing command, after 5ms interval
742 if (fail && --cmd->retries > 0) {
743 DPRINTK("SMU: i2c failure, starting timer...\n");
744 smu->i2c_timer.function = smu_i2c_retry;
745 smu->i2c_timer.data = (unsigned long)cmd;
746 smu->i2c_timer.expires = jiffies + msecs_to_jiffies(5);
747 add_timer(&smu->i2c_timer);
751 /* If failure or stage 1, command is complete */
752 if (fail || cmd->stage != 0) {
753 smu_i2c_complete_command(cmd, fail);
757 DPRINTK("SMU: going to stage 1\n");
759 /* Ok, initial command complete, now poll status */
760 scmd->reply_buf = cmd->pdata;
761 scmd->reply_len = 0x10;
762 scmd->data_buf = cmd->pdata;
771 int smu_queue_i2c(struct smu_i2c_cmd *cmd)
778 /* Fill most fields of scmd */
779 cmd->scmd.cmd = SMU_CMD_I2C_COMMAND;
780 cmd->scmd.done = smu_i2c_low_completion;
781 cmd->scmd.misc = cmd;
782 cmd->scmd.reply_buf = cmd->pdata;
783 cmd->scmd.reply_len = 0x10;
784 cmd->scmd.data_buf = (u8 *)(char *)&cmd->info;
785 cmd->scmd.status = 1;
787 cmd->pdata[0] = 0xff;
791 /* Check transfer type, sanitize some "info" fields
792 * based on transfer type and do more checking
794 cmd->info.caddr = cmd->info.devaddr;
795 cmd->read = cmd->info.devaddr & 0x01;
796 switch(cmd->info.type) {
797 case SMU_I2C_TRANSFER_SIMPLE:
798 memset(&cmd->info.sublen, 0, 4);
800 case SMU_I2C_TRANSFER_COMBINED:
801 cmd->info.devaddr &= 0xfe;
802 case SMU_I2C_TRANSFER_STDSUB:
803 if (cmd->info.sublen > 3)
810 /* Finish setting up command based on transfer direction
813 if (cmd->info.datalen > SMU_I2C_READ_MAX)
815 memset(cmd->info.data, 0xff, cmd->info.datalen);
816 cmd->scmd.data_len = 9;
818 if (cmd->info.datalen > SMU_I2C_WRITE_MAX)
820 cmd->scmd.data_len = 9 + cmd->info.datalen;
823 DPRINTK("SMU: i2c enqueuing command\n");
824 DPRINTK("SMU: %s, len=%d bus=%x addr=%x sub0=%x type=%x\n",
825 cmd->read ? "read" : "write", cmd->info.datalen,
826 cmd->info.bus, cmd->info.caddr,
827 cmd->info.subaddr[0], cmd->info.type);
830 /* Enqueue command in i2c list, and if empty, enqueue also in
833 spin_lock_irqsave(&smu->lock, flags);
834 if (smu->cmd_i2c_cur == NULL) {
835 smu->cmd_i2c_cur = cmd;
836 list_add_tail(&cmd->scmd.link, &smu->cmd_list);
837 if (smu->cmd_cur == NULL)
840 list_add_tail(&cmd->link, &smu->cmd_i2c_list);
841 spin_unlock_irqrestore(&smu->lock, flags);
849 * Userland driver interface
853 static LIST_HEAD(smu_clist);
854 static DEFINE_SPINLOCK(smu_clist_lock);
864 struct list_head list;
865 enum smu_file_mode mode;
869 wait_queue_head_t wait;
870 u8 buffer[SMU_MAX_DATA];
874 static int smu_open(struct inode *inode, struct file *file)
876 struct smu_private *pp;
879 pp = kmalloc(sizeof(struct smu_private), GFP_KERNEL);
882 memset(pp, 0, sizeof(struct smu_private));
883 spin_lock_init(&pp->lock);
884 pp->mode = smu_file_commands;
885 init_waitqueue_head(&pp->wait);
887 spin_lock_irqsave(&smu_clist_lock, flags);
888 list_add(&pp->list, &smu_clist);
889 spin_unlock_irqrestore(&smu_clist_lock, flags);
890 file->private_data = pp;
896 static void smu_user_cmd_done(struct smu_cmd *cmd, void *misc)
898 struct smu_private *pp = misc;
900 wake_up_all(&pp->wait);
904 static ssize_t smu_write(struct file *file, const char __user *buf,
905 size_t count, loff_t *ppos)
907 struct smu_private *pp = file->private_data;
909 struct smu_user_cmd_hdr hdr;
914 else if (copy_from_user(&hdr, buf, sizeof(hdr)))
916 else if (hdr.cmdtype == SMU_CMDTYPE_WANTS_EVENTS) {
917 pp->mode = smu_file_events;
919 } else if (hdr.cmdtype != SMU_CMDTYPE_SMU)
921 else if (pp->mode != smu_file_commands)
923 else if (hdr.data_len > SMU_MAX_DATA)
926 spin_lock_irqsave(&pp->lock, flags);
928 spin_unlock_irqrestore(&pp->lock, flags);
933 spin_unlock_irqrestore(&pp->lock, flags);
935 if (copy_from_user(pp->buffer, buf + sizeof(hdr), hdr.data_len)) {
940 pp->cmd.cmd = hdr.cmd;
941 pp->cmd.data_len = hdr.data_len;
942 pp->cmd.reply_len = SMU_MAX_DATA;
943 pp->cmd.data_buf = pp->buffer;
944 pp->cmd.reply_buf = pp->buffer;
945 pp->cmd.done = smu_user_cmd_done;
947 rc = smu_queue_cmd(&pp->cmd);
954 static ssize_t smu_read_command(struct file *file, struct smu_private *pp,
955 char __user *buf, size_t count)
957 DECLARE_WAITQUEUE(wait, current);
958 struct smu_user_reply_hdr hdr;
964 if (count < sizeof(struct smu_user_reply_hdr))
966 spin_lock_irqsave(&pp->lock, flags);
967 if (pp->cmd.status == 1) {
968 if (file->f_flags & O_NONBLOCK)
970 add_wait_queue(&pp->wait, &wait);
972 set_current_state(TASK_INTERRUPTIBLE);
974 if (pp->cmd.status != 1)
977 if (signal_pending(current))
979 spin_unlock_irqrestore(&pp->lock, flags);
981 spin_lock_irqsave(&pp->lock, flags);
983 set_current_state(TASK_RUNNING);
984 remove_wait_queue(&pp->wait, &wait);
986 spin_unlock_irqrestore(&pp->lock, flags);
989 if (pp->cmd.status != 0)
990 pp->cmd.reply_len = 0;
991 size = sizeof(hdr) + pp->cmd.reply_len;
995 hdr.status = pp->cmd.status;
996 hdr.reply_len = pp->cmd.reply_len;
997 if (copy_to_user(buf, &hdr, sizeof(hdr)))
1000 if (size && copy_to_user(buf + sizeof(hdr), pp->buffer, size))
1008 static ssize_t smu_read_events(struct file *file, struct smu_private *pp,
1009 char __user *buf, size_t count)
1011 /* Not implemented */
1012 msleep_interruptible(1000);
1017 static ssize_t smu_read(struct file *file, char __user *buf,
1018 size_t count, loff_t *ppos)
1020 struct smu_private *pp = file->private_data;
1022 if (pp->mode == smu_file_commands)
1023 return smu_read_command(file, pp, buf, count);
1024 if (pp->mode == smu_file_events)
1025 return smu_read_events(file, pp, buf, count);
1030 static unsigned int smu_fpoll(struct file *file, poll_table *wait)
1032 struct smu_private *pp = file->private_data;
1033 unsigned int mask = 0;
1034 unsigned long flags;
1039 if (pp->mode == smu_file_commands) {
1040 poll_wait(file, &pp->wait, wait);
1042 spin_lock_irqsave(&pp->lock, flags);
1043 if (pp->busy && pp->cmd.status != 1)
1045 spin_unlock_irqrestore(&pp->lock, flags);
1046 } if (pp->mode == smu_file_events) {
1047 /* Not yet implemented */
1052 static int smu_release(struct inode *inode, struct file *file)
1054 struct smu_private *pp = file->private_data;
1055 unsigned long flags;
1061 file->private_data = NULL;
1063 /* Mark file as closing to avoid races with new request */
1064 spin_lock_irqsave(&pp->lock, flags);
1065 pp->mode = smu_file_closing;
1068 /* Wait for any pending request to complete */
1069 if (busy && pp->cmd.status == 1) {
1070 DECLARE_WAITQUEUE(wait, current);
1072 add_wait_queue(&pp->wait, &wait);
1074 set_current_state(TASK_UNINTERRUPTIBLE);
1075 if (pp->cmd.status != 1)
1077 spin_lock_irqsave(&pp->lock, flags);
1079 spin_unlock_irqrestore(&pp->lock, flags);
1081 set_current_state(TASK_RUNNING);
1082 remove_wait_queue(&pp->wait, &wait);
1084 spin_unlock_irqrestore(&pp->lock, flags);
1086 spin_lock_irqsave(&smu_clist_lock, flags);
1087 list_del(&pp->list);
1088 spin_unlock_irqrestore(&smu_clist_lock, flags);
1095 static struct file_operations smu_device_fops __pmacdata = {
1096 .llseek = no_llseek,
1101 .release = smu_release,
1104 static struct miscdevice pmu_device __pmacdata = {
1105 MISC_DYNAMIC_MINOR, "smu", &smu_device_fops
1108 static int smu_device_init(void)
1112 if (misc_register(&pmu_device) < 0)
1113 printk(KERN_ERR "via-pmu: cannot register misc device.\n");
1116 device_initcall(smu_device_init);