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