Merge tag 'cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
[linux-2.6.git] / drivers / char / ps3flash.c
1 /*
2  * PS3 FLASH ROM Storage Driver
3  *
4  * Copyright (C) 2007 Sony Computer Entertainment Inc.
5  * Copyright 2007 Sony Corp.
6  *
7  * This program is free software; you can redistribute it and/or modify it
8  * under the terms of the GNU General Public License as published
9  * by the Free Software Foundation; version 2 of the License.
10  *
11  * This program is distributed in the hope that it will be useful, but
12  * WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License along
17  * with this program; if not, write to the Free Software Foundation, Inc.,
18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
19  */
20
21 #include <linux/fs.h>
22 #include <linux/miscdevice.h>
23 #include <linux/slab.h>
24 #include <linux/uaccess.h>
25 #include <linux/module.h>
26
27 #include <asm/lv1call.h>
28 #include <asm/ps3stor.h>
29
30
31 #define DEVICE_NAME             "ps3flash"
32
33 #define FLASH_BLOCK_SIZE        (256*1024)
34
35
36 struct ps3flash_private {
37         struct mutex mutex;     /* Bounce buffer mutex */
38         u64 chunk_sectors;
39         int tag;                /* Start sector of buffer, -1 if invalid */
40         bool dirty;
41 };
42
43 static struct ps3_storage_device *ps3flash_dev;
44
45 static int ps3flash_read_write_sectors(struct ps3_storage_device *dev,
46                                        u64 start_sector, int write)
47 {
48         struct ps3flash_private *priv = ps3_system_bus_get_drvdata(&dev->sbd);
49         u64 res = ps3stor_read_write_sectors(dev, dev->bounce_lpar,
50                                              start_sector, priv->chunk_sectors,
51                                              write);
52         if (res) {
53                 dev_err(&dev->sbd.core, "%s:%u: %s failed 0x%llx\n", __func__,
54                         __LINE__, write ? "write" : "read", res);
55                 return -EIO;
56         }
57         return 0;
58 }
59
60 static int ps3flash_writeback(struct ps3_storage_device *dev)
61 {
62         struct ps3flash_private *priv = ps3_system_bus_get_drvdata(&dev->sbd);
63         int res;
64
65         if (!priv->dirty || priv->tag < 0)
66                 return 0;
67
68         res = ps3flash_read_write_sectors(dev, priv->tag, 1);
69         if (res)
70                 return res;
71
72         priv->dirty = false;
73         return 0;
74 }
75
76 static int ps3flash_fetch(struct ps3_storage_device *dev, u64 start_sector)
77 {
78         struct ps3flash_private *priv = ps3_system_bus_get_drvdata(&dev->sbd);
79         int res;
80
81         if (start_sector == priv->tag)
82                 return 0;
83
84         res = ps3flash_writeback(dev);
85         if (res)
86                 return res;
87
88         priv->tag = -1;
89
90         res = ps3flash_read_write_sectors(dev, start_sector, 0);
91         if (res)
92                 return res;
93
94         priv->tag = start_sector;
95         return 0;
96 }
97
98 static loff_t ps3flash_llseek(struct file *file, loff_t offset, int origin)
99 {
100         struct ps3_storage_device *dev = ps3flash_dev;
101         loff_t res;
102
103         mutex_lock(&file->f_mapping->host->i_mutex);
104         switch (origin) {
105         case 0:
106                 break;
107         case 1:
108                 offset += file->f_pos;
109                 break;
110         case 2:
111                 offset += dev->regions[dev->region_idx].size*dev->blk_size;
112                 break;
113         default:
114                 offset = -1;
115         }
116         if (offset < 0) {
117                 res = -EINVAL;
118                 goto out;
119         }
120
121         file->f_pos = offset;
122         res = file->f_pos;
123
124 out:
125         mutex_unlock(&file->f_mapping->host->i_mutex);
126         return res;
127 }
128
129 static ssize_t ps3flash_read(char __user *userbuf, void *kernelbuf,
130                              size_t count, loff_t *pos)
131 {
132         struct ps3_storage_device *dev = ps3flash_dev;
133         struct ps3flash_private *priv = ps3_system_bus_get_drvdata(&dev->sbd);
134         u64 size, sector, offset;
135         int res;
136         size_t remaining, n;
137         const void *src;
138
139         dev_dbg(&dev->sbd.core,
140                 "%s:%u: Reading %zu bytes at position %lld to U0x%p/K0x%p\n",
141                 __func__, __LINE__, count, *pos, userbuf, kernelbuf);
142
143         size = dev->regions[dev->region_idx].size*dev->blk_size;
144         if (*pos >= size || !count)
145                 return 0;
146
147         if (*pos + count > size) {
148                 dev_dbg(&dev->sbd.core,
149                         "%s:%u Truncating count from %zu to %llu\n", __func__,
150                         __LINE__, count, size - *pos);
151                 count = size - *pos;
152         }
153
154         sector = *pos / dev->bounce_size * priv->chunk_sectors;
155         offset = *pos % dev->bounce_size;
156
157         remaining = count;
158         do {
159                 n = min_t(u64, remaining, dev->bounce_size - offset);
160                 src = dev->bounce_buf + offset;
161
162                 mutex_lock(&priv->mutex);
163
164                 res = ps3flash_fetch(dev, sector);
165                 if (res)
166                         goto fail;
167
168                 dev_dbg(&dev->sbd.core,
169                         "%s:%u: copy %lu bytes from 0x%p to U0x%p/K0x%p\n",
170                         __func__, __LINE__, n, src, userbuf, kernelbuf);
171                 if (userbuf) {
172                         if (copy_to_user(userbuf, src, n)) {
173                                 res = -EFAULT;
174                                 goto fail;
175                         }
176                         userbuf += n;
177                 }
178                 if (kernelbuf) {
179                         memcpy(kernelbuf, src, n);
180                         kernelbuf += n;
181                 }
182
183                 mutex_unlock(&priv->mutex);
184
185                 *pos += n;
186                 remaining -= n;
187                 sector += priv->chunk_sectors;
188                 offset = 0;
189         } while (remaining > 0);
190
191         return count;
192
193 fail:
194         mutex_unlock(&priv->mutex);
195         return res;
196 }
197
198 static ssize_t ps3flash_write(const char __user *userbuf,
199                               const void *kernelbuf, size_t count, loff_t *pos)
200 {
201         struct ps3_storage_device *dev = ps3flash_dev;
202         struct ps3flash_private *priv = ps3_system_bus_get_drvdata(&dev->sbd);
203         u64 size, sector, offset;
204         int res = 0;
205         size_t remaining, n;
206         void *dst;
207
208         dev_dbg(&dev->sbd.core,
209                 "%s:%u: Writing %zu bytes at position %lld from U0x%p/K0x%p\n",
210                 __func__, __LINE__, count, *pos, userbuf, kernelbuf);
211
212         size = dev->regions[dev->region_idx].size*dev->blk_size;
213         if (*pos >= size || !count)
214                 return 0;
215
216         if (*pos + count > size) {
217                 dev_dbg(&dev->sbd.core,
218                         "%s:%u Truncating count from %zu to %llu\n", __func__,
219                         __LINE__, count, size - *pos);
220                 count = size - *pos;
221         }
222
223         sector = *pos / dev->bounce_size * priv->chunk_sectors;
224         offset = *pos % dev->bounce_size;
225
226         remaining = count;
227         do {
228                 n = min_t(u64, remaining, dev->bounce_size - offset);
229                 dst = dev->bounce_buf + offset;
230
231                 mutex_lock(&priv->mutex);
232
233                 if (n != dev->bounce_size)
234                         res = ps3flash_fetch(dev, sector);
235                 else if (sector != priv->tag)
236                         res = ps3flash_writeback(dev);
237                 if (res)
238                         goto fail;
239
240                 dev_dbg(&dev->sbd.core,
241                         "%s:%u: copy %lu bytes from U0x%p/K0x%p to 0x%p\n",
242                         __func__, __LINE__, n, userbuf, kernelbuf, dst);
243                 if (userbuf) {
244                         if (copy_from_user(dst, userbuf, n)) {
245                                 res = -EFAULT;
246                                 goto fail;
247                         }
248                         userbuf += n;
249                 }
250                 if (kernelbuf) {
251                         memcpy(dst, kernelbuf, n);
252                         kernelbuf += n;
253                 }
254
255                 priv->tag = sector;
256                 priv->dirty = true;
257
258                 mutex_unlock(&priv->mutex);
259
260                 *pos += n;
261                 remaining -= n;
262                 sector += priv->chunk_sectors;
263                 offset = 0;
264         } while (remaining > 0);
265
266         return count;
267
268 fail:
269         mutex_unlock(&priv->mutex);
270         return res;
271 }
272
273 static ssize_t ps3flash_user_read(struct file *file, char __user *buf,
274                                   size_t count, loff_t *pos)
275 {
276         return ps3flash_read(buf, NULL, count, pos);
277 }
278
279 static ssize_t ps3flash_user_write(struct file *file, const char __user *buf,
280                                    size_t count, loff_t *pos)
281 {
282         return ps3flash_write(buf, NULL, count, pos);
283 }
284
285 static ssize_t ps3flash_kernel_read(void *buf, size_t count, loff_t pos)
286 {
287         return ps3flash_read(NULL, buf, count, &pos);
288 }
289
290 static ssize_t ps3flash_kernel_write(const void *buf, size_t count,
291                                      loff_t pos)
292 {
293         ssize_t res;
294         int wb;
295
296         res = ps3flash_write(NULL, buf, count, &pos);
297         if (res < 0)
298                 return res;
299
300         /* Make kernel writes synchronous */
301         wb = ps3flash_writeback(ps3flash_dev);
302         if (wb)
303                 return wb;
304
305         return res;
306 }
307
308 static int ps3flash_flush(struct file *file, fl_owner_t id)
309 {
310         return ps3flash_writeback(ps3flash_dev);
311 }
312
313 static int ps3flash_fsync(struct file *file, loff_t start, loff_t end, int datasync)
314 {
315         struct inode *inode = file->f_path.dentry->d_inode;
316         int err;
317         mutex_lock(&inode->i_mutex);
318         err = ps3flash_writeback(ps3flash_dev);
319         mutex_unlock(&inode->i_mutex);
320         return err;
321 }
322
323 static irqreturn_t ps3flash_interrupt(int irq, void *data)
324 {
325         struct ps3_storage_device *dev = data;
326         int res;
327         u64 tag, status;
328
329         res = lv1_storage_get_async_status(dev->sbd.dev_id, &tag, &status);
330
331         if (tag != dev->tag)
332                 dev_err(&dev->sbd.core,
333                         "%s:%u: tag mismatch, got %llx, expected %llx\n",
334                         __func__, __LINE__, tag, dev->tag);
335
336         if (res) {
337                 dev_err(&dev->sbd.core, "%s:%u: res=%d status=0x%llx\n",
338                         __func__, __LINE__, res, status);
339         } else {
340                 dev->lv1_status = status;
341                 complete(&dev->done);
342         }
343         return IRQ_HANDLED;
344 }
345
346 static const struct file_operations ps3flash_fops = {
347         .owner  = THIS_MODULE,
348         .llseek = ps3flash_llseek,
349         .read   = ps3flash_user_read,
350         .write  = ps3flash_user_write,
351         .flush  = ps3flash_flush,
352         .fsync  = ps3flash_fsync,
353 };
354
355 static const struct ps3_os_area_flash_ops ps3flash_kernel_ops = {
356         .read   = ps3flash_kernel_read,
357         .write  = ps3flash_kernel_write,
358 };
359
360 static struct miscdevice ps3flash_misc = {
361         .minor  = MISC_DYNAMIC_MINOR,
362         .name   = DEVICE_NAME,
363         .fops   = &ps3flash_fops,
364 };
365
366 static int __devinit ps3flash_probe(struct ps3_system_bus_device *_dev)
367 {
368         struct ps3_storage_device *dev = to_ps3_storage_device(&_dev->core);
369         struct ps3flash_private *priv;
370         int error;
371         unsigned long tmp;
372
373         tmp = dev->regions[dev->region_idx].start*dev->blk_size;
374         if (tmp % FLASH_BLOCK_SIZE) {
375                 dev_err(&dev->sbd.core,
376                         "%s:%u region start %lu is not aligned\n", __func__,
377                         __LINE__, tmp);
378                 return -EINVAL;
379         }
380         tmp = dev->regions[dev->region_idx].size*dev->blk_size;
381         if (tmp % FLASH_BLOCK_SIZE) {
382                 dev_err(&dev->sbd.core,
383                         "%s:%u region size %lu is not aligned\n", __func__,
384                         __LINE__, tmp);
385                 return -EINVAL;
386         }
387
388         /* use static buffer, kmalloc cannot allocate 256 KiB */
389         if (!ps3flash_bounce_buffer.address)
390                 return -ENODEV;
391
392         if (ps3flash_dev) {
393                 dev_err(&dev->sbd.core,
394                         "Only one FLASH device is supported\n");
395                 return -EBUSY;
396         }
397
398         ps3flash_dev = dev;
399
400         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
401         if (!priv) {
402                 error = -ENOMEM;
403                 goto fail;
404         }
405
406         ps3_system_bus_set_drvdata(&dev->sbd, priv);
407         mutex_init(&priv->mutex);
408         priv->tag = -1;
409
410         dev->bounce_size = ps3flash_bounce_buffer.size;
411         dev->bounce_buf = ps3flash_bounce_buffer.address;
412         priv->chunk_sectors = dev->bounce_size / dev->blk_size;
413
414         error = ps3stor_setup(dev, ps3flash_interrupt);
415         if (error)
416                 goto fail_free_priv;
417
418         ps3flash_misc.parent = &dev->sbd.core;
419         error = misc_register(&ps3flash_misc);
420         if (error) {
421                 dev_err(&dev->sbd.core, "%s:%u: misc_register failed %d\n",
422                         __func__, __LINE__, error);
423                 goto fail_teardown;
424         }
425
426         dev_info(&dev->sbd.core, "%s:%u: registered misc device %d\n",
427                  __func__, __LINE__, ps3flash_misc.minor);
428
429         ps3_os_area_flash_register(&ps3flash_kernel_ops);
430         return 0;
431
432 fail_teardown:
433         ps3stor_teardown(dev);
434 fail_free_priv:
435         kfree(priv);
436         ps3_system_bus_set_drvdata(&dev->sbd, NULL);
437 fail:
438         ps3flash_dev = NULL;
439         return error;
440 }
441
442 static int ps3flash_remove(struct ps3_system_bus_device *_dev)
443 {
444         struct ps3_storage_device *dev = to_ps3_storage_device(&_dev->core);
445
446         ps3_os_area_flash_register(NULL);
447         misc_deregister(&ps3flash_misc);
448         ps3stor_teardown(dev);
449         kfree(ps3_system_bus_get_drvdata(&dev->sbd));
450         ps3_system_bus_set_drvdata(&dev->sbd, NULL);
451         ps3flash_dev = NULL;
452         return 0;
453 }
454
455
456 static struct ps3_system_bus_driver ps3flash = {
457         .match_id       = PS3_MATCH_ID_STOR_FLASH,
458         .core.name      = DEVICE_NAME,
459         .core.owner     = THIS_MODULE,
460         .probe          = ps3flash_probe,
461         .remove         = ps3flash_remove,
462         .shutdown       = ps3flash_remove,
463 };
464
465
466 static int __init ps3flash_init(void)
467 {
468         return ps3_system_bus_driver_register(&ps3flash);
469 }
470
471 static void __exit ps3flash_exit(void)
472 {
473         ps3_system_bus_driver_unregister(&ps3flash);
474 }
475
476 module_init(ps3flash_init);
477 module_exit(ps3flash_exit);
478
479 MODULE_LICENSE("GPL");
480 MODULE_DESCRIPTION("PS3 FLASH ROM Storage Driver");
481 MODULE_AUTHOR("Sony Corporation");
482 MODULE_ALIAS(PS3_MODULE_ALIAS_STOR_FLASH);