pcmcia: CompactFlash driver for PA Semi Electra boards
[pv_ops_mirror.git] / drivers / misc / ibmasm / ibmasmfs.c
blob22a7e8ba211d242dd0b25c477f2ea5b7c4bcd07c
1 /*
2 * IBM ASM Service Processor Device Driver
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
18 * Copyright (C) IBM Corporation, 2004
20 * Author: Max Asböck <amax@us.ibm.com>
25 * Parts of this code are based on an article by Jonathan Corbet
26 * that appeared in Linux Weekly News.
31 * The IBMASM file virtual filesystem. It creates the following hierarchy
32 * dymamically when mounted from user space:
34 * /ibmasm
35 * |-- 0
36 * | |-- command
37 * | |-- event
38 * | |-- reverse_heartbeat
39 * | `-- remote_video
40 * | |-- depth
41 * | |-- height
42 * | `-- width
43 * .
44 * .
45 * .
46 * `-- n
47 * |-- command
48 * |-- event
49 * |-- reverse_heartbeat
50 * `-- remote_video
51 * |-- depth
52 * |-- height
53 * `-- width
55 * For each service processor the following files are created:
57 * command: execute dot commands
58 * write: execute a dot command on the service processor
59 * read: return the result of a previously executed dot command
61 * events: listen for service processor events
62 * read: sleep (interruptible) until an event occurs
63 * write: wakeup sleeping event listener
65 * reverse_heartbeat: send a heartbeat to the service processor
66 * read: sleep (interruptible) until the reverse heartbeat fails
67 * write: wakeup sleeping heartbeat listener
69 * remote_video/width
70 * remote_video/height
71 * remote_video/width: control remote display settings
72 * write: set value
73 * read: read value
76 #include <linux/fs.h>
77 #include <linux/pagemap.h>
78 #include <asm/uaccess.h>
79 #include <asm/io.h>
80 #include "ibmasm.h"
81 #include "remote.h"
82 #include "dot_command.h"
84 #define IBMASMFS_MAGIC 0x66726f67
86 static LIST_HEAD(service_processors);
88 static struct inode *ibmasmfs_make_inode(struct super_block *sb, int mode);
89 static void ibmasmfs_create_files (struct super_block *sb, struct dentry *root);
90 static int ibmasmfs_fill_super (struct super_block *sb, void *data, int silent);
93 static int ibmasmfs_get_super(struct file_system_type *fst,
94 int flags, const char *name, void *data,
95 struct vfsmount *mnt)
97 return get_sb_single(fst, flags, data, ibmasmfs_fill_super, mnt);
100 static struct super_operations ibmasmfs_s_ops = {
101 .statfs = simple_statfs,
102 .drop_inode = generic_delete_inode,
105 static const struct file_operations *ibmasmfs_dir_ops = &simple_dir_operations;
107 static struct file_system_type ibmasmfs_type = {
108 .owner = THIS_MODULE,
109 .name = "ibmasmfs",
110 .get_sb = ibmasmfs_get_super,
111 .kill_sb = kill_litter_super,
114 static int ibmasmfs_fill_super (struct super_block *sb, void *data, int silent)
116 struct inode *root;
117 struct dentry *root_dentry;
119 sb->s_blocksize = PAGE_CACHE_SIZE;
120 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
121 sb->s_magic = IBMASMFS_MAGIC;
122 sb->s_op = &ibmasmfs_s_ops;
123 sb->s_time_gran = 1;
125 root = ibmasmfs_make_inode (sb, S_IFDIR | 0500);
126 if (!root)
127 return -ENOMEM;
129 root->i_op = &simple_dir_inode_operations;
130 root->i_fop = ibmasmfs_dir_ops;
132 root_dentry = d_alloc_root(root);
133 if (!root_dentry) {
134 iput(root);
135 return -ENOMEM;
137 sb->s_root = root_dentry;
139 ibmasmfs_create_files(sb, root_dentry);
140 return 0;
143 static struct inode *ibmasmfs_make_inode(struct super_block *sb, int mode)
145 struct inode *ret = new_inode(sb);
147 if (ret) {
148 ret->i_mode = mode;
149 ret->i_uid = ret->i_gid = 0;
150 ret->i_blocks = 0;
151 ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
153 return ret;
156 static struct dentry *ibmasmfs_create_file (struct super_block *sb,
157 struct dentry *parent,
158 const char *name,
159 const struct file_operations *fops,
160 void *data,
161 int mode)
163 struct dentry *dentry;
164 struct inode *inode;
166 dentry = d_alloc_name(parent, name);
167 if (!dentry)
168 return NULL;
170 inode = ibmasmfs_make_inode(sb, S_IFREG | mode);
171 if (!inode) {
172 dput(dentry);
173 return NULL;
176 inode->i_fop = fops;
177 inode->i_private = data;
179 d_add(dentry, inode);
180 return dentry;
183 static struct dentry *ibmasmfs_create_dir (struct super_block *sb,
184 struct dentry *parent,
185 const char *name)
187 struct dentry *dentry;
188 struct inode *inode;
190 dentry = d_alloc_name(parent, name);
191 if (!dentry)
192 return NULL;
194 inode = ibmasmfs_make_inode(sb, S_IFDIR | 0500);
195 if (!inode) {
196 dput(dentry);
197 return NULL;
200 inode->i_op = &simple_dir_inode_operations;
201 inode->i_fop = ibmasmfs_dir_ops;
203 d_add(dentry, inode);
204 return dentry;
207 int ibmasmfs_register(void)
209 return register_filesystem(&ibmasmfs_type);
212 void ibmasmfs_unregister(void)
214 unregister_filesystem(&ibmasmfs_type);
217 void ibmasmfs_add_sp(struct service_processor *sp)
219 list_add(&sp->node, &service_processors);
222 /* struct to save state between command file operations */
223 struct ibmasmfs_command_data {
224 struct service_processor *sp;
225 struct command *command;
228 /* struct to save state between event file operations */
229 struct ibmasmfs_event_data {
230 struct service_processor *sp;
231 struct event_reader reader;
232 int active;
235 /* struct to save state between reverse heartbeat file operations */
236 struct ibmasmfs_heartbeat_data {
237 struct service_processor *sp;
238 struct reverse_heartbeat heartbeat;
239 int active;
242 static int command_file_open(struct inode *inode, struct file *file)
244 struct ibmasmfs_command_data *command_data;
246 if (!inode->i_private)
247 return -ENODEV;
249 command_data = kmalloc(sizeof(struct ibmasmfs_command_data), GFP_KERNEL);
250 if (!command_data)
251 return -ENOMEM;
253 command_data->command = NULL;
254 command_data->sp = inode->i_private;
255 file->private_data = command_data;
256 return 0;
259 static int command_file_close(struct inode *inode, struct file *file)
261 struct ibmasmfs_command_data *command_data = file->private_data;
263 if (command_data->command)
264 command_put(command_data->command);
266 kfree(command_data);
267 return 0;
270 static ssize_t command_file_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
272 struct ibmasmfs_command_data *command_data = file->private_data;
273 struct command *cmd;
274 int len;
275 unsigned long flags;
277 if (*offset < 0)
278 return -EINVAL;
279 if (count == 0 || count > IBMASM_CMD_MAX_BUFFER_SIZE)
280 return 0;
281 if (*offset != 0)
282 return 0;
284 spin_lock_irqsave(&command_data->sp->lock, flags);
285 cmd = command_data->command;
286 if (cmd == NULL) {
287 spin_unlock_irqrestore(&command_data->sp->lock, flags);
288 return 0;
290 command_data->command = NULL;
291 spin_unlock_irqrestore(&command_data->sp->lock, flags);
293 if (cmd->status != IBMASM_CMD_COMPLETE) {
294 command_put(cmd);
295 return -EIO;
297 len = min(count, cmd->buffer_size);
298 if (copy_to_user(buf, cmd->buffer, len)) {
299 command_put(cmd);
300 return -EFAULT;
302 command_put(cmd);
304 return len;
307 static ssize_t command_file_write(struct file *file, const char __user *ubuff, size_t count, loff_t *offset)
309 struct ibmasmfs_command_data *command_data = file->private_data;
310 struct command *cmd;
311 unsigned long flags;
313 if (*offset < 0)
314 return -EINVAL;
315 if (count == 0 || count > IBMASM_CMD_MAX_BUFFER_SIZE)
316 return 0;
317 if (*offset != 0)
318 return 0;
320 /* commands are executed sequentially, only one command at a time */
321 if (command_data->command)
322 return -EAGAIN;
324 cmd = ibmasm_new_command(command_data->sp, count);
325 if (!cmd)
326 return -ENOMEM;
328 if (copy_from_user(cmd->buffer, ubuff, count)) {
329 command_put(cmd);
330 return -EFAULT;
333 spin_lock_irqsave(&command_data->sp->lock, flags);
334 if (command_data->command) {
335 spin_unlock_irqrestore(&command_data->sp->lock, flags);
336 command_put(cmd);
337 return -EAGAIN;
339 command_data->command = cmd;
340 spin_unlock_irqrestore(&command_data->sp->lock, flags);
342 ibmasm_exec_command(command_data->sp, cmd);
343 ibmasm_wait_for_response(cmd, get_dot_command_timeout(cmd->buffer));
345 return count;
348 static int event_file_open(struct inode *inode, struct file *file)
350 struct ibmasmfs_event_data *event_data;
351 struct service_processor *sp;
353 if (!inode->i_private)
354 return -ENODEV;
356 sp = inode->i_private;
358 event_data = kmalloc(sizeof(struct ibmasmfs_event_data), GFP_KERNEL);
359 if (!event_data)
360 return -ENOMEM;
362 ibmasm_event_reader_register(sp, &event_data->reader);
364 event_data->sp = sp;
365 event_data->active = 0;
366 file->private_data = event_data;
367 return 0;
370 static int event_file_close(struct inode *inode, struct file *file)
372 struct ibmasmfs_event_data *event_data = file->private_data;
374 ibmasm_event_reader_unregister(event_data->sp, &event_data->reader);
375 kfree(event_data);
376 return 0;
379 static ssize_t event_file_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
381 struct ibmasmfs_event_data *event_data = file->private_data;
382 struct event_reader *reader = &event_data->reader;
383 struct service_processor *sp = event_data->sp;
384 int ret;
385 unsigned long flags;
387 if (*offset < 0)
388 return -EINVAL;
389 if (count == 0 || count > IBMASM_EVENT_MAX_SIZE)
390 return 0;
391 if (*offset != 0)
392 return 0;
394 spin_lock_irqsave(&sp->lock, flags);
395 if (event_data->active) {
396 spin_unlock_irqrestore(&sp->lock, flags);
397 return -EBUSY;
399 event_data->active = 1;
400 spin_unlock_irqrestore(&sp->lock, flags);
402 ret = ibmasm_get_next_event(sp, reader);
403 if (ret <= 0)
404 goto out;
406 if (count < reader->data_size) {
407 ret = -EINVAL;
408 goto out;
411 if (copy_to_user(buf, reader->data, reader->data_size)) {
412 ret = -EFAULT;
413 goto out;
415 ret = reader->data_size;
417 out:
418 event_data->active = 0;
419 return ret;
422 static ssize_t event_file_write(struct file *file, const char __user *buf, size_t count, loff_t *offset)
424 struct ibmasmfs_event_data *event_data = file->private_data;
426 if (*offset < 0)
427 return -EINVAL;
428 if (count != 1)
429 return 0;
430 if (*offset != 0)
431 return 0;
433 ibmasm_cancel_next_event(&event_data->reader);
434 return 0;
437 static int r_heartbeat_file_open(struct inode *inode, struct file *file)
439 struct ibmasmfs_heartbeat_data *rhbeat;
441 if (!inode->i_private)
442 return -ENODEV;
444 rhbeat = kmalloc(sizeof(struct ibmasmfs_heartbeat_data), GFP_KERNEL);
445 if (!rhbeat)
446 return -ENOMEM;
448 rhbeat->sp = inode->i_private;
449 rhbeat->active = 0;
450 ibmasm_init_reverse_heartbeat(rhbeat->sp, &rhbeat->heartbeat);
451 file->private_data = rhbeat;
452 return 0;
455 static int r_heartbeat_file_close(struct inode *inode, struct file *file)
457 struct ibmasmfs_heartbeat_data *rhbeat = file->private_data;
459 kfree(rhbeat);
460 return 0;
463 static ssize_t r_heartbeat_file_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
465 struct ibmasmfs_heartbeat_data *rhbeat = file->private_data;
466 unsigned long flags;
467 int result;
469 if (*offset < 0)
470 return -EINVAL;
471 if (count == 0 || count > 1024)
472 return 0;
473 if (*offset != 0)
474 return 0;
476 /* allow only one reverse heartbeat per process */
477 spin_lock_irqsave(&rhbeat->sp->lock, flags);
478 if (rhbeat->active) {
479 spin_unlock_irqrestore(&rhbeat->sp->lock, flags);
480 return -EBUSY;
482 rhbeat->active = 1;
483 spin_unlock_irqrestore(&rhbeat->sp->lock, flags);
485 result = ibmasm_start_reverse_heartbeat(rhbeat->sp, &rhbeat->heartbeat);
486 rhbeat->active = 0;
488 return result;
491 static ssize_t r_heartbeat_file_write(struct file *file, const char __user *buf, size_t count, loff_t *offset)
493 struct ibmasmfs_heartbeat_data *rhbeat = file->private_data;
495 if (*offset < 0)
496 return -EINVAL;
497 if (count != 1)
498 return 0;
499 if (*offset != 0)
500 return 0;
502 if (rhbeat->active)
503 ibmasm_stop_reverse_heartbeat(&rhbeat->heartbeat);
505 return 1;
508 static int remote_settings_file_open(struct inode *inode, struct file *file)
510 file->private_data = inode->i_private;
511 return 0;
514 static int remote_settings_file_close(struct inode *inode, struct file *file)
516 return 0;
519 static ssize_t remote_settings_file_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
521 void __iomem *address = (void __iomem *)file->private_data;
522 unsigned char *page;
523 int retval;
524 int len = 0;
525 unsigned int value;
527 if (*offset < 0)
528 return -EINVAL;
529 if (count == 0 || count > 1024)
530 return 0;
531 if (*offset != 0)
532 return 0;
534 page = (unsigned char *)__get_free_page(GFP_KERNEL);
535 if (!page)
536 return -ENOMEM;
538 value = readl(address);
539 len = sprintf(page, "%d\n", value);
541 if (copy_to_user(buf, page, len)) {
542 retval = -EFAULT;
543 goto exit;
545 *offset += len;
546 retval = len;
548 exit:
549 free_page((unsigned long)page);
550 return retval;
553 static ssize_t remote_settings_file_write(struct file *file, const char __user *ubuff, size_t count, loff_t *offset)
555 void __iomem *address = (void __iomem *)file->private_data;
556 char *buff;
557 unsigned int value;
559 if (*offset < 0)
560 return -EINVAL;
561 if (count == 0 || count > 1024)
562 return 0;
563 if (*offset != 0)
564 return 0;
566 buff = kzalloc (count + 1, GFP_KERNEL);
567 if (!buff)
568 return -ENOMEM;
571 if (copy_from_user(buff, ubuff, count)) {
572 kfree(buff);
573 return -EFAULT;
576 value = simple_strtoul(buff, NULL, 10);
577 writel(value, address);
578 kfree(buff);
580 return count;
583 static const struct file_operations command_fops = {
584 .open = command_file_open,
585 .release = command_file_close,
586 .read = command_file_read,
587 .write = command_file_write,
590 static const struct file_operations event_fops = {
591 .open = event_file_open,
592 .release = event_file_close,
593 .read = event_file_read,
594 .write = event_file_write,
597 static const struct file_operations r_heartbeat_fops = {
598 .open = r_heartbeat_file_open,
599 .release = r_heartbeat_file_close,
600 .read = r_heartbeat_file_read,
601 .write = r_heartbeat_file_write,
604 static const struct file_operations remote_settings_fops = {
605 .open = remote_settings_file_open,
606 .release = remote_settings_file_close,
607 .read = remote_settings_file_read,
608 .write = remote_settings_file_write,
612 static void ibmasmfs_create_files (struct super_block *sb, struct dentry *root)
614 struct list_head *entry;
615 struct service_processor *sp;
617 list_for_each(entry, &service_processors) {
618 struct dentry *dir;
619 struct dentry *remote_dir;
620 sp = list_entry(entry, struct service_processor, node);
621 dir = ibmasmfs_create_dir(sb, root, sp->dirname);
622 if (!dir)
623 continue;
625 ibmasmfs_create_file(sb, dir, "command", &command_fops, sp, S_IRUSR|S_IWUSR);
626 ibmasmfs_create_file(sb, dir, "event", &event_fops, sp, S_IRUSR|S_IWUSR);
627 ibmasmfs_create_file(sb, dir, "reverse_heartbeat", &r_heartbeat_fops, sp, S_IRUSR|S_IWUSR);
629 remote_dir = ibmasmfs_create_dir(sb, dir, "remote_video");
630 if (!remote_dir)
631 continue;
633 ibmasmfs_create_file(sb, remote_dir, "width", &remote_settings_fops, (void *)display_width(sp), S_IRUSR|S_IWUSR);
634 ibmasmfs_create_file(sb, remote_dir, "height", &remote_settings_fops, (void *)display_height(sp), S_IRUSR|S_IWUSR);
635 ibmasmfs_create_file(sb, remote_dir, "depth", &remote_settings_fops, (void *)display_depth(sp), S_IRUSR|S_IWUSR);