xref: /openbmc/linux/drivers/usb/storage/alauda.c (revision 22246614)
1 /*
2  * Driver for Alauda-based card readers
3  *
4  * Current development and maintenance by:
5  *   (c) 2005 Daniel Drake <dsd@gentoo.org>
6  *
7  * The 'Alauda' is a chip manufacturered by RATOC for OEM use.
8  *
9  * Alauda implements a vendor-specific command set to access two media reader
10  * ports (XD, SmartMedia). This driver converts SCSI commands to the commands
11  * which are accepted by these devices.
12  *
13  * The driver was developed through reverse-engineering, with the help of the
14  * sddr09 driver which has many similarities, and with some help from the
15  * (very old) vendor-supplied GPL sma03 driver.
16  *
17  * For protocol info, see http://alauda.sourceforge.net
18  *
19  * This program is free software; you can redistribute it and/or modify it
20  * under the terms of the GNU General Public License as published by the
21  * Free Software Foundation; either version 2, or (at your option) any
22  * later version.
23  *
24  * This program is distributed in the hope that it will be useful, but
25  * WITHOUT ANY WARRANTY; without even the implied warranty of
26  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
27  * General Public License for more details.
28  *
29  * You should have received a copy of the GNU General Public License along
30  * with this program; if not, write to the Free Software Foundation, Inc.,
31  * 675 Mass Ave, Cambridge, MA 02139, USA.
32  */
33 
34 #include <scsi/scsi.h>
35 #include <scsi/scsi_cmnd.h>
36 #include <scsi/scsi_device.h>
37 
38 #include "usb.h"
39 #include "transport.h"
40 #include "protocol.h"
41 #include "debug.h"
42 #include "alauda.h"
43 
44 #define short_pack(lsb,msb) ( ((u16)(lsb)) | ( ((u16)(msb))<<8 ) )
45 #define LSB_of(s) ((s)&0xFF)
46 #define MSB_of(s) ((s)>>8)
47 
48 #define MEDIA_PORT(us) us->srb->device->lun
49 #define MEDIA_INFO(us) ((struct alauda_info *)us->extra)->port[MEDIA_PORT(us)]
50 
51 #define PBA_LO(pba) ((pba & 0xF) << 5)
52 #define PBA_HI(pba) (pba >> 3)
53 #define PBA_ZONE(pba) (pba >> 11)
54 
55 /*
56  * Media handling
57  */
58 
59 struct alauda_card_info {
60 	unsigned char id;		/* id byte */
61 	unsigned char chipshift;	/* 1<<cs bytes total capacity */
62 	unsigned char pageshift;	/* 1<<ps bytes in a page */
63 	unsigned char blockshift;	/* 1<<bs pages per block */
64 	unsigned char zoneshift;	/* 1<<zs blocks per zone */
65 };
66 
67 static struct alauda_card_info alauda_card_ids[] = {
68 	/* NAND flash */
69 	{ 0x6e, 20, 8, 4, 8},	/* 1 MB */
70 	{ 0xe8, 20, 8, 4, 8},	/* 1 MB */
71 	{ 0xec, 20, 8, 4, 8},	/* 1 MB */
72 	{ 0x64, 21, 8, 4, 9}, 	/* 2 MB */
73 	{ 0xea, 21, 8, 4, 9},	/* 2 MB */
74 	{ 0x6b, 22, 9, 4, 9},	/* 4 MB */
75 	{ 0xe3, 22, 9, 4, 9},	/* 4 MB */
76 	{ 0xe5, 22, 9, 4, 9},	/* 4 MB */
77 	{ 0xe6, 23, 9, 4, 10},	/* 8 MB */
78 	{ 0x73, 24, 9, 5, 10},	/* 16 MB */
79 	{ 0x75, 25, 9, 5, 10},	/* 32 MB */
80 	{ 0x76, 26, 9, 5, 10},	/* 64 MB */
81 	{ 0x79, 27, 9, 5, 10},	/* 128 MB */
82 	{ 0x71, 28, 9, 5, 10},	/* 256 MB */
83 
84 	/* MASK ROM */
85 	{ 0x5d, 21, 9, 4, 8},	/* 2 MB */
86 	{ 0xd5, 22, 9, 4, 9},	/* 4 MB */
87 	{ 0xd6, 23, 9, 4, 10},	/* 8 MB */
88 	{ 0x57, 24, 9, 4, 11},	/* 16 MB */
89 	{ 0x58, 25, 9, 4, 12},	/* 32 MB */
90 	{ 0,}
91 };
92 
93 static struct alauda_card_info *alauda_card_find_id(unsigned char id) {
94 	int i;
95 
96 	for (i = 0; alauda_card_ids[i].id != 0; i++)
97 		if (alauda_card_ids[i].id == id)
98 			return &(alauda_card_ids[i]);
99 	return NULL;
100 }
101 
102 /*
103  * ECC computation.
104  */
105 
106 static unsigned char parity[256];
107 static unsigned char ecc2[256];
108 
109 static void nand_init_ecc(void) {
110 	int i, j, a;
111 
112 	parity[0] = 0;
113 	for (i = 1; i < 256; i++)
114 		parity[i] = (parity[i&(i-1)] ^ 1);
115 
116 	for (i = 0; i < 256; i++) {
117 		a = 0;
118 		for (j = 0; j < 8; j++) {
119 			if (i & (1<<j)) {
120 				if ((j & 1) == 0)
121 					a ^= 0x04;
122 				if ((j & 2) == 0)
123 					a ^= 0x10;
124 				if ((j & 4) == 0)
125 					a ^= 0x40;
126 			}
127 		}
128 		ecc2[i] = ~(a ^ (a<<1) ^ (parity[i] ? 0xa8 : 0));
129 	}
130 }
131 
132 /* compute 3-byte ecc on 256 bytes */
133 static void nand_compute_ecc(unsigned char *data, unsigned char *ecc) {
134 	int i, j, a;
135 	unsigned char par, bit, bits[8];
136 
137 	par = 0;
138 	for (j = 0; j < 8; j++)
139 		bits[j] = 0;
140 
141 	/* collect 16 checksum bits */
142 	for (i = 0; i < 256; i++) {
143 		par ^= data[i];
144 		bit = parity[data[i]];
145 		for (j = 0; j < 8; j++)
146 			if ((i & (1<<j)) == 0)
147 				bits[j] ^= bit;
148 	}
149 
150 	/* put 4+4+4 = 12 bits in the ecc */
151 	a = (bits[3] << 6) + (bits[2] << 4) + (bits[1] << 2) + bits[0];
152 	ecc[0] = ~(a ^ (a<<1) ^ (parity[par] ? 0xaa : 0));
153 
154 	a = (bits[7] << 6) + (bits[6] << 4) + (bits[5] << 2) + bits[4];
155 	ecc[1] = ~(a ^ (a<<1) ^ (parity[par] ? 0xaa : 0));
156 
157 	ecc[2] = ecc2[par];
158 }
159 
160 static int nand_compare_ecc(unsigned char *data, unsigned char *ecc) {
161 	return (data[0] == ecc[0] && data[1] == ecc[1] && data[2] == ecc[2]);
162 }
163 
164 static void nand_store_ecc(unsigned char *data, unsigned char *ecc) {
165 	memcpy(data, ecc, 3);
166 }
167 
168 /*
169  * Alauda driver
170  */
171 
172 /*
173  * Forget our PBA <---> LBA mappings for a particular port
174  */
175 static void alauda_free_maps (struct alauda_media_info *media_info)
176 {
177 	unsigned int shift = media_info->zoneshift
178 		+ media_info->blockshift + media_info->pageshift;
179 	unsigned int num_zones = media_info->capacity >> shift;
180 	unsigned int i;
181 
182 	if (media_info->lba_to_pba != NULL)
183 		for (i = 0; i < num_zones; i++) {
184 			kfree(media_info->lba_to_pba[i]);
185 			media_info->lba_to_pba[i] = NULL;
186 		}
187 
188 	if (media_info->pba_to_lba != NULL)
189 		for (i = 0; i < num_zones; i++) {
190 			kfree(media_info->pba_to_lba[i]);
191 			media_info->pba_to_lba[i] = NULL;
192 		}
193 }
194 
195 /*
196  * Returns 2 bytes of status data
197  * The first byte describes media status, and second byte describes door status
198  */
199 static int alauda_get_media_status(struct us_data *us, unsigned char *data)
200 {
201 	int rc;
202 	unsigned char command;
203 
204 	if (MEDIA_PORT(us) == ALAUDA_PORT_XD)
205 		command = ALAUDA_GET_XD_MEDIA_STATUS;
206 	else
207 		command = ALAUDA_GET_SM_MEDIA_STATUS;
208 
209 	rc = usb_stor_ctrl_transfer(us, us->recv_ctrl_pipe,
210 		command, 0xc0, 0, 1, data, 2);
211 
212 	US_DEBUGP("alauda_get_media_status: Media status %02X %02X\n",
213 		data[0], data[1]);
214 
215 	return rc;
216 }
217 
218 /*
219  * Clears the "media was changed" bit so that we know when it changes again
220  * in the future.
221  */
222 static int alauda_ack_media(struct us_data *us)
223 {
224 	unsigned char command;
225 
226 	if (MEDIA_PORT(us) == ALAUDA_PORT_XD)
227 		command = ALAUDA_ACK_XD_MEDIA_CHANGE;
228 	else
229 		command = ALAUDA_ACK_SM_MEDIA_CHANGE;
230 
231 	return usb_stor_ctrl_transfer(us, us->send_ctrl_pipe,
232 		command, 0x40, 0, 1, NULL, 0);
233 }
234 
235 /*
236  * Retrieves a 4-byte media signature, which indicates manufacturer, capacity,
237  * and some other details.
238  */
239 static int alauda_get_media_signature(struct us_data *us, unsigned char *data)
240 {
241 	unsigned char command;
242 
243 	if (MEDIA_PORT(us) == ALAUDA_PORT_XD)
244 		command = ALAUDA_GET_XD_MEDIA_SIG;
245 	else
246 		command = ALAUDA_GET_SM_MEDIA_SIG;
247 
248 	return usb_stor_ctrl_transfer(us, us->recv_ctrl_pipe,
249 		command, 0xc0, 0, 0, data, 4);
250 }
251 
252 /*
253  * Resets the media status (but not the whole device?)
254  */
255 static int alauda_reset_media(struct us_data *us)
256 {
257 	unsigned char *command = us->iobuf;
258 
259 	memset(command, 0, 9);
260 	command[0] = ALAUDA_BULK_CMD;
261 	command[1] = ALAUDA_BULK_RESET_MEDIA;
262 	command[8] = MEDIA_PORT(us);
263 
264 	return usb_stor_bulk_transfer_buf(us, us->send_bulk_pipe,
265 		command, 9, NULL);
266 }
267 
268 /*
269  * Examines the media and deduces capacity, etc.
270  */
271 static int alauda_init_media(struct us_data *us)
272 {
273 	unsigned char *data = us->iobuf;
274 	int ready = 0;
275 	struct alauda_card_info *media_info;
276 	unsigned int num_zones;
277 
278 	while (ready == 0) {
279 		msleep(20);
280 
281 		if (alauda_get_media_status(us, data) != USB_STOR_XFER_GOOD)
282 			return USB_STOR_TRANSPORT_ERROR;
283 
284 		if (data[0] & 0x10)
285 			ready = 1;
286 	}
287 
288 	US_DEBUGP("alauda_init_media: We are ready for action!\n");
289 
290 	if (alauda_ack_media(us) != USB_STOR_XFER_GOOD)
291 		return USB_STOR_TRANSPORT_ERROR;
292 
293 	msleep(10);
294 
295 	if (alauda_get_media_status(us, data) != USB_STOR_XFER_GOOD)
296 		return USB_STOR_TRANSPORT_ERROR;
297 
298 	if (data[0] != 0x14) {
299 		US_DEBUGP("alauda_init_media: Media not ready after ack\n");
300 		return USB_STOR_TRANSPORT_ERROR;
301 	}
302 
303 	if (alauda_get_media_signature(us, data) != USB_STOR_XFER_GOOD)
304 		return USB_STOR_TRANSPORT_ERROR;
305 
306 	US_DEBUGP("alauda_init_media: Media signature: %02X %02X %02X %02X\n",
307 		data[0], data[1], data[2], data[3]);
308 	media_info = alauda_card_find_id(data[1]);
309 	if (media_info == NULL) {
310 		printk("alauda_init_media: Unrecognised media signature: "
311 			"%02X %02X %02X %02X\n",
312 			data[0], data[1], data[2], data[3]);
313 		return USB_STOR_TRANSPORT_ERROR;
314 	}
315 
316 	MEDIA_INFO(us).capacity = 1 << media_info->chipshift;
317 	US_DEBUGP("Found media with capacity: %ldMB\n",
318 		MEDIA_INFO(us).capacity >> 20);
319 
320 	MEDIA_INFO(us).pageshift = media_info->pageshift;
321 	MEDIA_INFO(us).blockshift = media_info->blockshift;
322 	MEDIA_INFO(us).zoneshift = media_info->zoneshift;
323 
324 	MEDIA_INFO(us).pagesize = 1 << media_info->pageshift;
325 	MEDIA_INFO(us).blocksize = 1 << media_info->blockshift;
326 	MEDIA_INFO(us).zonesize = 1 << media_info->zoneshift;
327 
328 	MEDIA_INFO(us).uzonesize = ((1 << media_info->zoneshift) / 128) * 125;
329 	MEDIA_INFO(us).blockmask = MEDIA_INFO(us).blocksize - 1;
330 
331 	num_zones = MEDIA_INFO(us).capacity >> (MEDIA_INFO(us).zoneshift
332 		+ MEDIA_INFO(us).blockshift + MEDIA_INFO(us).pageshift);
333 	MEDIA_INFO(us).pba_to_lba = kcalloc(num_zones, sizeof(u16*), GFP_NOIO);
334 	MEDIA_INFO(us).lba_to_pba = kcalloc(num_zones, sizeof(u16*), GFP_NOIO);
335 
336 	if (alauda_reset_media(us) != USB_STOR_XFER_GOOD)
337 		return USB_STOR_TRANSPORT_ERROR;
338 
339 	return USB_STOR_TRANSPORT_GOOD;
340 }
341 
342 /*
343  * Examines the media status and does the right thing when the media has gone,
344  * appeared, or changed.
345  */
346 static int alauda_check_media(struct us_data *us)
347 {
348 	struct alauda_info *info = (struct alauda_info *) us->extra;
349 	unsigned char status[2];
350 	int rc;
351 
352 	rc = alauda_get_media_status(us, status);
353 
354 	/* Check for no media or door open */
355 	if ((status[0] & 0x80) || ((status[0] & 0x1F) == 0x10)
356 		|| ((status[1] & 0x01) == 0)) {
357 		US_DEBUGP("alauda_check_media: No media, or door open\n");
358 		alauda_free_maps(&MEDIA_INFO(us));
359 		info->sense_key = 0x02;
360 		info->sense_asc = 0x3A;
361 		info->sense_ascq = 0x00;
362 		return USB_STOR_TRANSPORT_FAILED;
363 	}
364 
365 	/* Check for media change */
366 	if (status[0] & 0x08) {
367 		US_DEBUGP("alauda_check_media: Media change detected\n");
368 		alauda_free_maps(&MEDIA_INFO(us));
369 		alauda_init_media(us);
370 
371 		info->sense_key = UNIT_ATTENTION;
372 		info->sense_asc = 0x28;
373 		info->sense_ascq = 0x00;
374 		return USB_STOR_TRANSPORT_FAILED;
375 	}
376 
377 	return USB_STOR_TRANSPORT_GOOD;
378 }
379 
380 /*
381  * Checks the status from the 2nd status register
382  * Returns 3 bytes of status data, only the first is known
383  */
384 static int alauda_check_status2(struct us_data *us)
385 {
386 	int rc;
387 	unsigned char command[] = {
388 		ALAUDA_BULK_CMD, ALAUDA_BULK_GET_STATUS2,
389 		0, 0, 0, 0, 3, 0, MEDIA_PORT(us)
390 	};
391 	unsigned char data[3];
392 
393 	rc = usb_stor_bulk_transfer_buf(us, us->send_bulk_pipe,
394 		command, 9, NULL);
395 	if (rc != USB_STOR_XFER_GOOD)
396 		return rc;
397 
398 	rc = usb_stor_bulk_transfer_buf(us, us->recv_bulk_pipe,
399 		data, 3, NULL);
400 	if (rc != USB_STOR_XFER_GOOD)
401 		return rc;
402 
403 	US_DEBUGP("alauda_check_status2: %02X %02X %02X\n", data[0], data[1], data[2]);
404 	if (data[0] & ALAUDA_STATUS_ERROR)
405 		return USB_STOR_XFER_ERROR;
406 
407 	return USB_STOR_XFER_GOOD;
408 }
409 
410 /*
411  * Gets the redundancy data for the first page of a PBA
412  * Returns 16 bytes.
413  */
414 static int alauda_get_redu_data(struct us_data *us, u16 pba, unsigned char *data)
415 {
416 	int rc;
417 	unsigned char command[] = {
418 		ALAUDA_BULK_CMD, ALAUDA_BULK_GET_REDU_DATA,
419 		PBA_HI(pba), PBA_ZONE(pba), 0, PBA_LO(pba), 0, 0, MEDIA_PORT(us)
420 	};
421 
422 	rc = usb_stor_bulk_transfer_buf(us, us->send_bulk_pipe,
423 		command, 9, NULL);
424 	if (rc != USB_STOR_XFER_GOOD)
425 		return rc;
426 
427 	return usb_stor_bulk_transfer_buf(us, us->recv_bulk_pipe,
428 		data, 16, NULL);
429 }
430 
431 /*
432  * Finds the first unused PBA in a zone
433  * Returns the absolute PBA of an unused PBA, or 0 if none found.
434  */
435 static u16 alauda_find_unused_pba(struct alauda_media_info *info,
436 	unsigned int zone)
437 {
438 	u16 *pba_to_lba = info->pba_to_lba[zone];
439 	unsigned int i;
440 
441 	for (i = 0; i < info->zonesize; i++)
442 		if (pba_to_lba[i] == UNDEF)
443 			return (zone << info->zoneshift) + i;
444 
445 	return 0;
446 }
447 
448 /*
449  * Reads the redundancy data for all PBA's in a zone
450  * Produces lba <--> pba mappings
451  */
452 static int alauda_read_map(struct us_data *us, unsigned int zone)
453 {
454 	unsigned char *data = us->iobuf;
455 	int result;
456 	int i, j;
457 	unsigned int zonesize = MEDIA_INFO(us).zonesize;
458 	unsigned int uzonesize = MEDIA_INFO(us).uzonesize;
459 	unsigned int lba_offset, lba_real, blocknum;
460 	unsigned int zone_base_lba = zone * uzonesize;
461 	unsigned int zone_base_pba = zone * zonesize;
462 	u16 *lba_to_pba = kcalloc(zonesize, sizeof(u16), GFP_NOIO);
463 	u16 *pba_to_lba = kcalloc(zonesize, sizeof(u16), GFP_NOIO);
464 	if (lba_to_pba == NULL || pba_to_lba == NULL) {
465 		result = USB_STOR_TRANSPORT_ERROR;
466 		goto error;
467 	}
468 
469 	US_DEBUGP("alauda_read_map: Mapping blocks for zone %d\n", zone);
470 
471 	/* 1024 PBA's per zone */
472 	for (i = 0; i < zonesize; i++)
473 		lba_to_pba[i] = pba_to_lba[i] = UNDEF;
474 
475 	for (i = 0; i < zonesize; i++) {
476 		blocknum = zone_base_pba + i;
477 
478 		result = alauda_get_redu_data(us, blocknum, data);
479 		if (result != USB_STOR_XFER_GOOD) {
480 			result = USB_STOR_TRANSPORT_ERROR;
481 			goto error;
482 		}
483 
484 		/* special PBAs have control field 0^16 */
485 		for (j = 0; j < 16; j++)
486 			if (data[j] != 0)
487 				goto nonz;
488 		pba_to_lba[i] = UNUSABLE;
489 		US_DEBUGP("alauda_read_map: PBA %d has no logical mapping\n", blocknum);
490 		continue;
491 
492 	nonz:
493 		/* unwritten PBAs have control field FF^16 */
494 		for (j = 0; j < 16; j++)
495 			if (data[j] != 0xff)
496 				goto nonff;
497 		continue;
498 
499 	nonff:
500 		/* normal PBAs start with six FFs */
501 		if (j < 6) {
502 			US_DEBUGP("alauda_read_map: PBA %d has no logical mapping: "
503 			       "reserved area = %02X%02X%02X%02X "
504 			       "data status %02X block status %02X\n",
505 			       blocknum, data[0], data[1], data[2], data[3],
506 			       data[4], data[5]);
507 			pba_to_lba[i] = UNUSABLE;
508 			continue;
509 		}
510 
511 		if ((data[6] >> 4) != 0x01) {
512 			US_DEBUGP("alauda_read_map: PBA %d has invalid address "
513 			       "field %02X%02X/%02X%02X\n",
514 			       blocknum, data[6], data[7], data[11], data[12]);
515 			pba_to_lba[i] = UNUSABLE;
516 			continue;
517 		}
518 
519 		/* check even parity */
520 		if (parity[data[6] ^ data[7]]) {
521 			printk("alauda_read_map: Bad parity in LBA for block %d"
522 			       " (%02X %02X)\n", i, data[6], data[7]);
523 			pba_to_lba[i] = UNUSABLE;
524 			continue;
525 		}
526 
527 		lba_offset = short_pack(data[7], data[6]);
528 		lba_offset = (lba_offset & 0x07FF) >> 1;
529 		lba_real = lba_offset + zone_base_lba;
530 
531 		/*
532 		 * Every 1024 physical blocks ("zone"), the LBA numbers
533 		 * go back to zero, but are within a higher block of LBA's.
534 		 * Also, there is a maximum of 1000 LBA's per zone.
535 		 * In other words, in PBA 1024-2047 you will find LBA 0-999
536 		 * which are really LBA 1000-1999. This allows for 24 bad
537 		 * or special physical blocks per zone.
538 		 */
539 
540 		if (lba_offset >= uzonesize) {
541 			printk("alauda_read_map: Bad low LBA %d for block %d\n",
542 			       lba_real, blocknum);
543 			continue;
544 		}
545 
546 		if (lba_to_pba[lba_offset] != UNDEF) {
547 			printk("alauda_read_map: LBA %d seen for PBA %d and %d\n",
548 			       lba_real, lba_to_pba[lba_offset], blocknum);
549 			continue;
550 		}
551 
552 		pba_to_lba[i] = lba_real;
553 		lba_to_pba[lba_offset] = blocknum;
554 		continue;
555 	}
556 
557 	MEDIA_INFO(us).lba_to_pba[zone] = lba_to_pba;
558 	MEDIA_INFO(us).pba_to_lba[zone] = pba_to_lba;
559 	result = 0;
560 	goto out;
561 
562 error:
563 	kfree(lba_to_pba);
564 	kfree(pba_to_lba);
565 out:
566 	return result;
567 }
568 
569 /*
570  * Checks to see whether we have already mapped a certain zone
571  * If we haven't, the map is generated
572  */
573 static void alauda_ensure_map_for_zone(struct us_data *us, unsigned int zone)
574 {
575 	if (MEDIA_INFO(us).lba_to_pba[zone] == NULL
576 		|| MEDIA_INFO(us).pba_to_lba[zone] == NULL)
577 		alauda_read_map(us, zone);
578 }
579 
580 /*
581  * Erases an entire block
582  */
583 static int alauda_erase_block(struct us_data *us, u16 pba)
584 {
585 	int rc;
586 	unsigned char command[] = {
587 		ALAUDA_BULK_CMD, ALAUDA_BULK_ERASE_BLOCK, PBA_HI(pba),
588 		PBA_ZONE(pba), 0, PBA_LO(pba), 0x02, 0, MEDIA_PORT(us)
589 	};
590 	unsigned char buf[2];
591 
592 	US_DEBUGP("alauda_erase_block: Erasing PBA %d\n", pba);
593 
594 	rc = usb_stor_bulk_transfer_buf(us, us->send_bulk_pipe,
595 		command, 9, NULL);
596 	if (rc != USB_STOR_XFER_GOOD)
597 		return rc;
598 
599 	rc = usb_stor_bulk_transfer_buf(us, us->recv_bulk_pipe,
600 		buf, 2, NULL);
601 	if (rc != USB_STOR_XFER_GOOD)
602 		return rc;
603 
604 	US_DEBUGP("alauda_erase_block: Erase result: %02X %02X\n",
605 		buf[0], buf[1]);
606 	return rc;
607 }
608 
609 /*
610  * Reads data from a certain offset page inside a PBA, including interleaved
611  * redundancy data. Returns (pagesize+64)*pages bytes in data.
612  */
613 static int alauda_read_block_raw(struct us_data *us, u16 pba,
614 		unsigned int page, unsigned int pages, unsigned char *data)
615 {
616 	int rc;
617 	unsigned char command[] = {
618 		ALAUDA_BULK_CMD, ALAUDA_BULK_READ_BLOCK, PBA_HI(pba),
619 		PBA_ZONE(pba), 0, PBA_LO(pba) + page, pages, 0, MEDIA_PORT(us)
620 	};
621 
622 	US_DEBUGP("alauda_read_block: pba %d page %d count %d\n",
623 		pba, page, pages);
624 
625 	rc = usb_stor_bulk_transfer_buf(us, us->send_bulk_pipe,
626 		command, 9, NULL);
627 	if (rc != USB_STOR_XFER_GOOD)
628 		return rc;
629 
630 	return usb_stor_bulk_transfer_buf(us, us->recv_bulk_pipe,
631 		data, (MEDIA_INFO(us).pagesize + 64) * pages, NULL);
632 }
633 
634 /*
635  * Reads data from a certain offset page inside a PBA, excluding redundancy
636  * data. Returns pagesize*pages bytes in data. Note that data must be big enough
637  * to hold (pagesize+64)*pages bytes of data, but you can ignore those 'extra'
638  * trailing bytes outside this function.
639  */
640 static int alauda_read_block(struct us_data *us, u16 pba,
641 		unsigned int page, unsigned int pages, unsigned char *data)
642 {
643 	int i, rc;
644 	unsigned int pagesize = MEDIA_INFO(us).pagesize;
645 
646 	rc = alauda_read_block_raw(us, pba, page, pages, data);
647 	if (rc != USB_STOR_XFER_GOOD)
648 		return rc;
649 
650 	/* Cut out the redundancy data */
651 	for (i = 0; i < pages; i++) {
652 		int dest_offset = i * pagesize;
653 		int src_offset = i * (pagesize + 64);
654 		memmove(data + dest_offset, data + src_offset, pagesize);
655 	}
656 
657 	return rc;
658 }
659 
660 /*
661  * Writes an entire block of data and checks status after write.
662  * Redundancy data must be already included in data. Data should be
663  * (pagesize+64)*blocksize bytes in length.
664  */
665 static int alauda_write_block(struct us_data *us, u16 pba, unsigned char *data)
666 {
667 	int rc;
668 	struct alauda_info *info = (struct alauda_info *) us->extra;
669 	unsigned char command[] = {
670 		ALAUDA_BULK_CMD, ALAUDA_BULK_WRITE_BLOCK, PBA_HI(pba),
671 		PBA_ZONE(pba), 0, PBA_LO(pba), 32, 0, MEDIA_PORT(us)
672 	};
673 
674 	US_DEBUGP("alauda_write_block: pba %d\n", pba);
675 
676 	rc = usb_stor_bulk_transfer_buf(us, us->send_bulk_pipe,
677 		command, 9, NULL);
678 	if (rc != USB_STOR_XFER_GOOD)
679 		return rc;
680 
681 	rc = usb_stor_bulk_transfer_buf(us, info->wr_ep, data,
682 		(MEDIA_INFO(us).pagesize + 64) * MEDIA_INFO(us).blocksize,
683 		NULL);
684 	if (rc != USB_STOR_XFER_GOOD)
685 		return rc;
686 
687 	return alauda_check_status2(us);
688 }
689 
690 /*
691  * Write some data to a specific LBA.
692  */
693 static int alauda_write_lba(struct us_data *us, u16 lba,
694 		 unsigned int page, unsigned int pages,
695 		 unsigned char *ptr, unsigned char *blockbuffer)
696 {
697 	u16 pba, lbap, new_pba;
698 	unsigned char *bptr, *cptr, *xptr;
699 	unsigned char ecc[3];
700 	int i, result;
701 	unsigned int uzonesize = MEDIA_INFO(us).uzonesize;
702 	unsigned int zonesize = MEDIA_INFO(us).zonesize;
703 	unsigned int pagesize = MEDIA_INFO(us).pagesize;
704 	unsigned int blocksize = MEDIA_INFO(us).blocksize;
705 	unsigned int lba_offset = lba % uzonesize;
706 	unsigned int new_pba_offset;
707 	unsigned int zone = lba / uzonesize;
708 
709 	alauda_ensure_map_for_zone(us, zone);
710 
711 	pba = MEDIA_INFO(us).lba_to_pba[zone][lba_offset];
712 	if (pba == 1) {
713 		/* Maybe it is impossible to write to PBA 1.
714 		   Fake success, but don't do anything. */
715 		printk("alauda_write_lba: avoid writing to pba 1\n");
716 		return USB_STOR_TRANSPORT_GOOD;
717 	}
718 
719 	new_pba = alauda_find_unused_pba(&MEDIA_INFO(us), zone);
720 	if (!new_pba) {
721 		printk("alauda_write_lba: Out of unused blocks\n");
722 		return USB_STOR_TRANSPORT_ERROR;
723 	}
724 
725 	/* read old contents */
726 	if (pba != UNDEF) {
727 		result = alauda_read_block_raw(us, pba, 0,
728 			blocksize, blockbuffer);
729 		if (result != USB_STOR_XFER_GOOD)
730 			return result;
731 	} else {
732 		memset(blockbuffer, 0, blocksize * (pagesize + 64));
733 	}
734 
735 	lbap = (lba_offset << 1) | 0x1000;
736 	if (parity[MSB_of(lbap) ^ LSB_of(lbap)])
737 		lbap ^= 1;
738 
739 	/* check old contents and fill lba */
740 	for (i = 0; i < blocksize; i++) {
741 		bptr = blockbuffer + (i * (pagesize + 64));
742 		cptr = bptr + pagesize;
743 		nand_compute_ecc(bptr, ecc);
744 		if (!nand_compare_ecc(cptr+13, ecc)) {
745 			US_DEBUGP("Warning: bad ecc in page %d- of pba %d\n",
746 				  i, pba);
747 			nand_store_ecc(cptr+13, ecc);
748 		}
749 		nand_compute_ecc(bptr + (pagesize / 2), ecc);
750 		if (!nand_compare_ecc(cptr+8, ecc)) {
751 			US_DEBUGP("Warning: bad ecc in page %d+ of pba %d\n",
752 				  i, pba);
753 			nand_store_ecc(cptr+8, ecc);
754 		}
755 		cptr[6] = cptr[11] = MSB_of(lbap);
756 		cptr[7] = cptr[12] = LSB_of(lbap);
757 	}
758 
759 	/* copy in new stuff and compute ECC */
760 	xptr = ptr;
761 	for (i = page; i < page+pages; i++) {
762 		bptr = blockbuffer + (i * (pagesize + 64));
763 		cptr = bptr + pagesize;
764 		memcpy(bptr, xptr, pagesize);
765 		xptr += pagesize;
766 		nand_compute_ecc(bptr, ecc);
767 		nand_store_ecc(cptr+13, ecc);
768 		nand_compute_ecc(bptr + (pagesize / 2), ecc);
769 		nand_store_ecc(cptr+8, ecc);
770 	}
771 
772 	result = alauda_write_block(us, new_pba, blockbuffer);
773 	if (result != USB_STOR_XFER_GOOD)
774 		return result;
775 
776 	new_pba_offset = new_pba - (zone * zonesize);
777 	MEDIA_INFO(us).pba_to_lba[zone][new_pba_offset] = lba;
778 	MEDIA_INFO(us).lba_to_pba[zone][lba_offset] = new_pba;
779 	US_DEBUGP("alauda_write_lba: Remapped LBA %d to PBA %d\n",
780 		lba, new_pba);
781 
782 	if (pba != UNDEF) {
783 		unsigned int pba_offset = pba - (zone * zonesize);
784 		result = alauda_erase_block(us, pba);
785 		if (result != USB_STOR_XFER_GOOD)
786 			return result;
787 		MEDIA_INFO(us).pba_to_lba[zone][pba_offset] = UNDEF;
788 	}
789 
790 	return USB_STOR_TRANSPORT_GOOD;
791 }
792 
793 /*
794  * Read data from a specific sector address
795  */
796 static int alauda_read_data(struct us_data *us, unsigned long address,
797 		unsigned int sectors)
798 {
799 	unsigned char *buffer;
800 	u16 lba, max_lba;
801 	unsigned int page, len, offset;
802 	unsigned int blockshift = MEDIA_INFO(us).blockshift;
803 	unsigned int pageshift = MEDIA_INFO(us).pageshift;
804 	unsigned int blocksize = MEDIA_INFO(us).blocksize;
805 	unsigned int pagesize = MEDIA_INFO(us).pagesize;
806 	unsigned int uzonesize = MEDIA_INFO(us).uzonesize;
807 	struct scatterlist *sg;
808 	int result;
809 
810 	/*
811 	 * Since we only read in one block at a time, we have to create
812 	 * a bounce buffer and move the data a piece at a time between the
813 	 * bounce buffer and the actual transfer buffer.
814 	 * We make this buffer big enough to hold temporary redundancy data,
815 	 * which we use when reading the data blocks.
816 	 */
817 
818 	len = min(sectors, blocksize) * (pagesize + 64);
819 	buffer = kmalloc(len, GFP_NOIO);
820 	if (buffer == NULL) {
821 		printk("alauda_read_data: Out of memory\n");
822 		return USB_STOR_TRANSPORT_ERROR;
823 	}
824 
825 	/* Figure out the initial LBA and page */
826 	lba = address >> blockshift;
827 	page = (address & MEDIA_INFO(us).blockmask);
828 	max_lba = MEDIA_INFO(us).capacity >> (blockshift + pageshift);
829 
830 	result = USB_STOR_TRANSPORT_GOOD;
831 	offset = 0;
832 	sg = NULL;
833 
834 	while (sectors > 0) {
835 		unsigned int zone = lba / uzonesize; /* integer division */
836 		unsigned int lba_offset = lba - (zone * uzonesize);
837 		unsigned int pages;
838 		u16 pba;
839 		alauda_ensure_map_for_zone(us, zone);
840 
841 		/* Not overflowing capacity? */
842 		if (lba >= max_lba) {
843 			US_DEBUGP("Error: Requested lba %u exceeds "
844 				  "maximum %u\n", lba, max_lba);
845 			result = USB_STOR_TRANSPORT_ERROR;
846 			break;
847 		}
848 
849 		/* Find number of pages we can read in this block */
850 		pages = min(sectors, blocksize - page);
851 		len = pages << pageshift;
852 
853 		/* Find where this lba lives on disk */
854 		pba = MEDIA_INFO(us).lba_to_pba[zone][lba_offset];
855 
856 		if (pba == UNDEF) {	/* this lba was never written */
857 			US_DEBUGP("Read %d zero pages (LBA %d) page %d\n",
858 				  pages, lba, page);
859 
860 			/* This is not really an error. It just means
861 			   that the block has never been written.
862 			   Instead of returning USB_STOR_TRANSPORT_ERROR
863 			   it is better to return all zero data. */
864 
865 			memset(buffer, 0, len);
866 		} else {
867 			US_DEBUGP("Read %d pages, from PBA %d"
868 				  " (LBA %d) page %d\n",
869 				  pages, pba, lba, page);
870 
871 			result = alauda_read_block(us, pba, page, pages, buffer);
872 			if (result != USB_STOR_TRANSPORT_GOOD)
873 				break;
874 		}
875 
876 		/* Store the data in the transfer buffer */
877 		usb_stor_access_xfer_buf(buffer, len, us->srb,
878 				&sg, &offset, TO_XFER_BUF);
879 
880 		page = 0;
881 		lba++;
882 		sectors -= pages;
883 	}
884 
885 	kfree(buffer);
886 	return result;
887 }
888 
889 /*
890  * Write data to a specific sector address
891  */
892 static int alauda_write_data(struct us_data *us, unsigned long address,
893 		unsigned int sectors)
894 {
895 	unsigned char *buffer, *blockbuffer;
896 	unsigned int page, len, offset;
897 	unsigned int blockshift = MEDIA_INFO(us).blockshift;
898 	unsigned int pageshift = MEDIA_INFO(us).pageshift;
899 	unsigned int blocksize = MEDIA_INFO(us).blocksize;
900 	unsigned int pagesize = MEDIA_INFO(us).pagesize;
901 	struct scatterlist *sg;
902 	u16 lba, max_lba;
903 	int result;
904 
905 	/*
906 	 * Since we don't write the user data directly to the device,
907 	 * we have to create a bounce buffer and move the data a piece
908 	 * at a time between the bounce buffer and the actual transfer buffer.
909 	 */
910 
911 	len = min(sectors, blocksize) * pagesize;
912 	buffer = kmalloc(len, GFP_NOIO);
913 	if (buffer == NULL) {
914 		printk("alauda_write_data: Out of memory\n");
915 		return USB_STOR_TRANSPORT_ERROR;
916 	}
917 
918 	/*
919 	 * We also need a temporary block buffer, where we read in the old data,
920 	 * overwrite parts with the new data, and manipulate the redundancy data
921 	 */
922 	blockbuffer = kmalloc((pagesize + 64) * blocksize, GFP_NOIO);
923 	if (blockbuffer == NULL) {
924 		printk("alauda_write_data: Out of memory\n");
925 		kfree(buffer);
926 		return USB_STOR_TRANSPORT_ERROR;
927 	}
928 
929 	/* Figure out the initial LBA and page */
930 	lba = address >> blockshift;
931 	page = (address & MEDIA_INFO(us).blockmask);
932 	max_lba = MEDIA_INFO(us).capacity >> (pageshift + blockshift);
933 
934 	result = USB_STOR_TRANSPORT_GOOD;
935 	offset = 0;
936 	sg = NULL;
937 
938 	while (sectors > 0) {
939 		/* Write as many sectors as possible in this block */
940 		unsigned int pages = min(sectors, blocksize - page);
941 		len = pages << pageshift;
942 
943 		/* Not overflowing capacity? */
944 		if (lba >= max_lba) {
945 			US_DEBUGP("alauda_write_data: Requested lba %u exceeds "
946 				  "maximum %u\n", lba, max_lba);
947 			result = USB_STOR_TRANSPORT_ERROR;
948 			break;
949 		}
950 
951 		/* Get the data from the transfer buffer */
952 		usb_stor_access_xfer_buf(buffer, len, us->srb,
953 				&sg, &offset, FROM_XFER_BUF);
954 
955 		result = alauda_write_lba(us, lba, page, pages, buffer,
956 			blockbuffer);
957 		if (result != USB_STOR_TRANSPORT_GOOD)
958 			break;
959 
960 		page = 0;
961 		lba++;
962 		sectors -= pages;
963 	}
964 
965 	kfree(buffer);
966 	kfree(blockbuffer);
967 	return result;
968 }
969 
970 /*
971  * Our interface with the rest of the world
972  */
973 
974 static void alauda_info_destructor(void *extra)
975 {
976 	struct alauda_info *info = (struct alauda_info *) extra;
977 	int port;
978 
979 	if (!info)
980 		return;
981 
982 	for (port = 0; port < 2; port++) {
983 		struct alauda_media_info *media_info = &info->port[port];
984 
985 		alauda_free_maps(media_info);
986 		kfree(media_info->lba_to_pba);
987 		kfree(media_info->pba_to_lba);
988 	}
989 }
990 
991 /*
992  * Initialize alauda_info struct and find the data-write endpoint
993  */
994 int init_alauda(struct us_data *us)
995 {
996 	struct alauda_info *info;
997 	struct usb_host_interface *altsetting = us->pusb_intf->cur_altsetting;
998 	nand_init_ecc();
999 
1000 	us->extra = kzalloc(sizeof(struct alauda_info), GFP_NOIO);
1001 	if (!us->extra) {
1002 		US_DEBUGP("init_alauda: Gah! Can't allocate storage for"
1003 			"alauda info struct!\n");
1004 		return USB_STOR_TRANSPORT_ERROR;
1005 	}
1006 	info = (struct alauda_info *) us->extra;
1007 	us->extra_destructor = alauda_info_destructor;
1008 
1009 	info->wr_ep = usb_sndbulkpipe(us->pusb_dev,
1010 		altsetting->endpoint[0].desc.bEndpointAddress
1011 		& USB_ENDPOINT_NUMBER_MASK);
1012 
1013 	return USB_STOR_TRANSPORT_GOOD;
1014 }
1015 
1016 int alauda_transport(struct scsi_cmnd *srb, struct us_data *us)
1017 {
1018 	int rc;
1019 	struct alauda_info *info = (struct alauda_info *) us->extra;
1020 	unsigned char *ptr = us->iobuf;
1021 	static unsigned char inquiry_response[36] = {
1022 		0x00, 0x80, 0x00, 0x01, 0x1F, 0x00, 0x00, 0x00
1023 	};
1024 
1025 	if (srb->cmnd[0] == INQUIRY) {
1026 		US_DEBUGP("alauda_transport: INQUIRY. "
1027 			"Returning bogus response.\n");
1028 		memcpy(ptr, inquiry_response, sizeof(inquiry_response));
1029 		fill_inquiry_response(us, ptr, 36);
1030 		return USB_STOR_TRANSPORT_GOOD;
1031 	}
1032 
1033 	if (srb->cmnd[0] == TEST_UNIT_READY) {
1034 		US_DEBUGP("alauda_transport: TEST_UNIT_READY.\n");
1035 		return alauda_check_media(us);
1036 	}
1037 
1038 	if (srb->cmnd[0] == READ_CAPACITY) {
1039 		unsigned int num_zones;
1040 		unsigned long capacity;
1041 
1042 		rc = alauda_check_media(us);
1043 		if (rc != USB_STOR_TRANSPORT_GOOD)
1044 			return rc;
1045 
1046 		num_zones = MEDIA_INFO(us).capacity >> (MEDIA_INFO(us).zoneshift
1047 			+ MEDIA_INFO(us).blockshift + MEDIA_INFO(us).pageshift);
1048 
1049 		capacity = num_zones * MEDIA_INFO(us).uzonesize
1050 			* MEDIA_INFO(us).blocksize;
1051 
1052 		/* Report capacity and page size */
1053 		((__be32 *) ptr)[0] = cpu_to_be32(capacity - 1);
1054 		((__be32 *) ptr)[1] = cpu_to_be32(512);
1055 
1056 		usb_stor_set_xfer_buf(ptr, 8, srb);
1057 		return USB_STOR_TRANSPORT_GOOD;
1058 	}
1059 
1060 	if (srb->cmnd[0] == READ_10) {
1061 		unsigned int page, pages;
1062 
1063 		rc = alauda_check_media(us);
1064 		if (rc != USB_STOR_TRANSPORT_GOOD)
1065 			return rc;
1066 
1067 		page = short_pack(srb->cmnd[3], srb->cmnd[2]);
1068 		page <<= 16;
1069 		page |= short_pack(srb->cmnd[5], srb->cmnd[4]);
1070 		pages = short_pack(srb->cmnd[8], srb->cmnd[7]);
1071 
1072 		US_DEBUGP("alauda_transport: READ_10: page %d pagect %d\n",
1073 			  page, pages);
1074 
1075 		return alauda_read_data(us, page, pages);
1076 	}
1077 
1078 	if (srb->cmnd[0] == WRITE_10) {
1079 		unsigned int page, pages;
1080 
1081 		rc = alauda_check_media(us);
1082 		if (rc != USB_STOR_TRANSPORT_GOOD)
1083 			return rc;
1084 
1085 		page = short_pack(srb->cmnd[3], srb->cmnd[2]);
1086 		page <<= 16;
1087 		page |= short_pack(srb->cmnd[5], srb->cmnd[4]);
1088 		pages = short_pack(srb->cmnd[8], srb->cmnd[7]);
1089 
1090 		US_DEBUGP("alauda_transport: WRITE_10: page %d pagect %d\n",
1091 			  page, pages);
1092 
1093 		return alauda_write_data(us, page, pages);
1094 	}
1095 
1096 	if (srb->cmnd[0] == REQUEST_SENSE) {
1097 		US_DEBUGP("alauda_transport: REQUEST_SENSE.\n");
1098 
1099 		memset(ptr, 0, 18);
1100 		ptr[0] = 0xF0;
1101 		ptr[2] = info->sense_key;
1102 		ptr[7] = 11;
1103 		ptr[12] = info->sense_asc;
1104 		ptr[13] = info->sense_ascq;
1105 		usb_stor_set_xfer_buf(ptr, 18, srb);
1106 
1107 		return USB_STOR_TRANSPORT_GOOD;
1108 	}
1109 
1110 	if (srb->cmnd[0] == ALLOW_MEDIUM_REMOVAL) {
1111 		/* sure.  whatever.  not like we can stop the user from popping
1112 		   the media out of the device (no locking doors, etc) */
1113 		return USB_STOR_TRANSPORT_GOOD;
1114 	}
1115 
1116 	US_DEBUGP("alauda_transport: Gah! Unknown command: %d (0x%x)\n",
1117 		srb->cmnd[0], srb->cmnd[0]);
1118 	info->sense_key = 0x05;
1119 	info->sense_asc = 0x20;
1120 	info->sense_ascq = 0x00;
1121 	return USB_STOR_TRANSPORT_FAILED;
1122 }
1123 
1124