1/*
2 *  drivers/mtd/nand/rtc_from4.c
3 *
4 *  Copyright (C) 2004  Red Hat, Inc.
5 *
6 *  Derived from drivers/mtd/nand/spia.c
7 *       Copyright (C) 2000 Steven J. Hill (sjhill@realitydiluted.com)
8 *
9 * $Id: rtc_from4.c,v 1.1.1.1 2007/08/03 18:52:44 Exp $
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License version 2 as
13 * published by the Free Software Foundation.
14 *
15 * Overview:
16 *   This is a device driver for the AG-AND flash device found on the
17 *   Renesas Technology Corp. Flash ROM 4-slot interface board (FROM_BOARD4),
18 *   which utilizes the Renesas HN29V1G91T-30 part.
19 *   This chip is a 1 GBibit (128MiB x 8 bits) AG-AND flash device.
20 */
21
22#include <linux/delay.h>
23#include <linux/kernel.h>
24#include <linux/init.h>
25#include <linux/slab.h>
26#include <linux/rslib.h>
27#include <linux/bitrev.h>
28#include <linux/module.h>
29#include <linux/mtd/compatmac.h>
30#include <linux/mtd/mtd.h>
31#include <linux/mtd/nand.h>
32#include <linux/mtd/partitions.h>
33#include <asm/io.h>
34
35/*
36 * MTD structure for Renesas board
37 */
38static struct mtd_info *rtc_from4_mtd = NULL;
39
40#define RTC_FROM4_MAX_CHIPS	2
41
42/* HS77x9 processor register defines */
43#define SH77X9_BCR1	((volatile unsigned short *)(0xFFFFFF60))
44#define SH77X9_BCR2	((volatile unsigned short *)(0xFFFFFF62))
45#define SH77X9_WCR1	((volatile unsigned short *)(0xFFFFFF64))
46#define SH77X9_WCR2	((volatile unsigned short *)(0xFFFFFF66))
47#define SH77X9_MCR	((volatile unsigned short *)(0xFFFFFF68))
48#define SH77X9_PCR	((volatile unsigned short *)(0xFFFFFF6C))
49#define SH77X9_FRQCR	((volatile unsigned short *)(0xFFFFFF80))
50
51/*
52 * Values specific to the Renesas Technology Corp. FROM_BOARD4 (used with HS77x9 processor)
53 */
54/* Address where flash is mapped */
55#define RTC_FROM4_FIO_BASE	0x14000000
56
57/* CLE and ALE are tied to address lines 5 & 4, respectively */
58#define RTC_FROM4_CLE		(1 << 5)
59#define RTC_FROM4_ALE		(1 << 4)
60
61/* address lines A24-A22 used for chip selection */
62#define RTC_FROM4_NAND_ADDR_SLOT3	(0x00800000)
63#define RTC_FROM4_NAND_ADDR_SLOT4	(0x00C00000)
64#define RTC_FROM4_NAND_ADDR_FPGA	(0x01000000)
65/* mask address lines A24-A22 used for chip selection */
66#define RTC_FROM4_NAND_ADDR_MASK	(RTC_FROM4_NAND_ADDR_SLOT3 | RTC_FROM4_NAND_ADDR_SLOT4 | RTC_FROM4_NAND_ADDR_FPGA)
67
68/* FPGA status register for checking device ready (bit zero) */
69#define RTC_FROM4_FPGA_SR		(RTC_FROM4_NAND_ADDR_FPGA | 0x00000002)
70#define RTC_FROM4_DEVICE_READY		0x0001
71
72/* FPGA Reed-Solomon ECC Control register */
73
74#define RTC_FROM4_RS_ECC_CTL		(RTC_FROM4_NAND_ADDR_FPGA | 0x00000050)
75#define RTC_FROM4_RS_ECC_CTL_CLR	(1 << 7)
76#define RTC_FROM4_RS_ECC_CTL_GEN	(1 << 6)
77#define RTC_FROM4_RS_ECC_CTL_FD_E	(1 << 5)
78
79/* FPGA Reed-Solomon ECC code base */
80#define RTC_FROM4_RS_ECC		(RTC_FROM4_NAND_ADDR_FPGA | 0x00000060)
81#define RTC_FROM4_RS_ECCN		(RTC_FROM4_NAND_ADDR_FPGA | 0x00000080)
82
83/* FPGA Reed-Solomon ECC check register */
84#define RTC_FROM4_RS_ECC_CHK		(RTC_FROM4_NAND_ADDR_FPGA | 0x00000070)
85#define RTC_FROM4_RS_ECC_CHK_ERROR	(1 << 7)
86
87#define ERR_STAT_ECC_AVAILABLE		0x20
88
89/* Undefine for software ECC */
90#define RTC_FROM4_HWECC	1
91
92/* Define as 1 for no virtual erase blocks (in JFFS2) */
93#define RTC_FROM4_NO_VIRTBLOCKS	0
94
95/*
96 * Module stuff
97 */
98static void __iomem *rtc_from4_fio_base = (void *)P2SEGADDR(RTC_FROM4_FIO_BASE);
99
100static const struct mtd_partition partition_info[] = {
101	{
102	 .name = "Renesas flash partition 1",
103	 .offset = 0,
104	 .size = MTDPART_SIZ_FULL},
105};
106
107#define NUM_PARTITIONS 1
108
109/*
110 *	hardware specific flash bbt decriptors
111 *	Note: this is to allow debugging by disabling
112 *		NAND_BBT_CREATE and/or NAND_BBT_WRITE
113 *
114 */
115static uint8_t bbt_pattern[] = { 'B', 'b', 't', '0' };
116static uint8_t mirror_pattern[] = { '1', 't', 'b', 'B' };
117
118static struct nand_bbt_descr rtc_from4_bbt_main_descr = {
119	.options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE
120		| NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP,
121	.offs = 40,
122	.len = 4,
123	.veroffs = 44,
124	.maxblocks = 4,
125	.pattern = bbt_pattern
126};
127
128static struct nand_bbt_descr rtc_from4_bbt_mirror_descr = {
129	.options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE
130		| NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP,
131	.offs = 40,
132	.len = 4,
133	.veroffs = 44,
134	.maxblocks = 4,
135	.pattern = mirror_pattern
136};
137
138#ifdef RTC_FROM4_HWECC
139
140/* the Reed Solomon control structure */
141static struct rs_control *rs_decoder;
142
143/*
144 *      hardware specific Out Of Band information
145 */
146static struct nand_ecclayout rtc_from4_nand_oobinfo = {
147	.eccbytes = 32,
148	.eccpos = {
149		   0, 1, 2, 3, 4, 5, 6, 7,
150		   8, 9, 10, 11, 12, 13, 14, 15,
151		   16, 17, 18, 19, 20, 21, 22, 23,
152		   24, 25, 26, 27, 28, 29, 30, 31},
153	.oobfree = {{32, 32}}
154};
155
156#endif
157
158/*
159 * rtc_from4_hwcontrol - hardware specific access to control-lines
160 * @mtd:	MTD device structure
161 * @cmd:	hardware control command
162 *
163 * Address lines (A5 and A4) are used to control Command and Address Latch
164 * Enable on this board, so set the read/write address appropriately.
165 *
166 * Chip Enable is also controlled by the Chip Select (CS5) and
167 * Address lines (A24-A22), so no action is required here.
168 *
169 */
170static void rtc_from4_hwcontrol(struct mtd_info *mtd, int cmd,
171				unsigned int ctrl)
172{
173	struct nand_chip *chip = (mtd->priv);
174
175	if (cmd == NAND_CMD_NONE)
176		return;
177
178	if (ctrl & NAND_CLE)
179		writeb(cmd, chip->IO_ADDR_W | RTC_FROM4_CLE);
180	else
181		writeb(cmd, chip->IO_ADDR_W | RTC_FROM4_ALE);
182}
183
184/*
185 * rtc_from4_nand_select_chip - hardware specific chip select
186 * @mtd:	MTD device structure
187 * @chip:	Chip to select (0 == slot 3, 1 == slot 4)
188 *
189 * The chip select is based on address lines A24-A22.
190 * This driver uses flash slots 3 and 4 (A23-A22).
191 *
192 */
193static void rtc_from4_nand_select_chip(struct mtd_info *mtd, int chip)
194{
195	struct nand_chip *this = mtd->priv;
196
197	this->IO_ADDR_R = (void __iomem *)((unsigned long)this->IO_ADDR_R & ~RTC_FROM4_NAND_ADDR_MASK);
198	this->IO_ADDR_W = (void __iomem *)((unsigned long)this->IO_ADDR_W & ~RTC_FROM4_NAND_ADDR_MASK);
199
200	switch (chip) {
201
202	case 0:		/* select slot 3 chip */
203		this->IO_ADDR_R = (void __iomem *)((unsigned long)this->IO_ADDR_R | RTC_FROM4_NAND_ADDR_SLOT3);
204		this->IO_ADDR_W = (void __iomem *)((unsigned long)this->IO_ADDR_W | RTC_FROM4_NAND_ADDR_SLOT3);
205		break;
206	case 1:		/* select slot 4 chip */
207		this->IO_ADDR_R = (void __iomem *)((unsigned long)this->IO_ADDR_R | RTC_FROM4_NAND_ADDR_SLOT4);
208		this->IO_ADDR_W = (void __iomem *)((unsigned long)this->IO_ADDR_W | RTC_FROM4_NAND_ADDR_SLOT4);
209		break;
210
211	}
212}
213
214/*
215 * rtc_from4_nand_device_ready - hardware specific ready/busy check
216 * @mtd:	MTD device structure
217 *
218 * This board provides the Ready/Busy state in the status register
219 * of the FPGA.  Bit zero indicates the RDY(1)/BSY(0) signal.
220 *
221 */
222static int rtc_from4_nand_device_ready(struct mtd_info *mtd)
223{
224	unsigned short status;
225
226	status = *((volatile unsigned short *)(rtc_from4_fio_base + RTC_FROM4_FPGA_SR));
227
228	return (status & RTC_FROM4_DEVICE_READY);
229
230}
231
232/*
233 * deplete - code to perform device recovery in case there was a power loss
234 * @mtd:	MTD device structure
235 * @chip:	Chip to select (0 == slot 3, 1 == slot 4)
236 *
237 * If there was a sudden loss of power during an erase operation, a
238 * "device recovery" operation must be performed when power is restored
239 * to ensure correct operation.  This routine performs the required steps
240 * for the requested chip.
241 *
242 * See page 86 of the data sheet for details.
243 *
244 */
245static void deplete(struct mtd_info *mtd, int chip)
246{
247	struct nand_chip *this = mtd->priv;
248
249	/* wait until device is ready */
250	while (!this->dev_ready(mtd)) ;
251
252	this->select_chip(mtd, chip);
253
254	/* Send the commands for device recovery, phase 1 */
255	this->cmdfunc(mtd, NAND_CMD_DEPLETE1, 0x0000, 0x0000);
256	this->cmdfunc(mtd, NAND_CMD_DEPLETE2, -1, -1);
257
258	/* Send the commands for device recovery, phase 2 */
259	this->cmdfunc(mtd, NAND_CMD_DEPLETE1, 0x0000, 0x0004);
260	this->cmdfunc(mtd, NAND_CMD_DEPLETE2, -1, -1);
261
262}
263
264#ifdef RTC_FROM4_HWECC
265/*
266 * rtc_from4_enable_hwecc - hardware specific hardware ECC enable function
267 * @mtd:	MTD device structure
268 * @mode:	I/O mode; read or write
269 *
270 * enable hardware ECC for data read or write
271 *
272 */
273static void rtc_from4_enable_hwecc(struct mtd_info *mtd, int mode)
274{
275	volatile unsigned short *rs_ecc_ctl = (volatile unsigned short *)(rtc_from4_fio_base + RTC_FROM4_RS_ECC_CTL);
276	unsigned short status;
277
278	switch (mode) {
279	case NAND_ECC_READ:
280		status = RTC_FROM4_RS_ECC_CTL_CLR | RTC_FROM4_RS_ECC_CTL_FD_E;
281
282		*rs_ecc_ctl = status;
283		break;
284
285	case NAND_ECC_READSYN:
286		status = 0x00;
287
288		*rs_ecc_ctl = status;
289		break;
290
291	case NAND_ECC_WRITE:
292		status = RTC_FROM4_RS_ECC_CTL_CLR | RTC_FROM4_RS_ECC_CTL_GEN | RTC_FROM4_RS_ECC_CTL_FD_E;
293
294		*rs_ecc_ctl = status;
295		break;
296
297	default:
298		BUG();
299		break;
300	}
301
302}
303
304/*
305 * rtc_from4_calculate_ecc - hardware specific code to read ECC code
306 * @mtd:	MTD device structure
307 * @dat:	buffer containing the data to generate ECC codes
308 * @ecc_code	ECC codes calculated
309 *
310 * The ECC code is calculated by the FPGA.  All we have to do is read the values
311 * from the FPGA registers.
312 *
313 * Note: We read from the inverted registers, since data is inverted before
314 * the code is calculated. So all 0xff data (blank page) results in all 0xff rs code
315 *
316 */
317static void rtc_from4_calculate_ecc(struct mtd_info *mtd, const u_char *dat, u_char *ecc_code)
318{
319	volatile unsigned short *rs_eccn = (volatile unsigned short *)(rtc_from4_fio_base + RTC_FROM4_RS_ECCN);
320	unsigned short value;
321	int i;
322
323	for (i = 0; i < 8; i++) {
324		value = *rs_eccn;
325		ecc_code[i] = (unsigned char)value;
326		rs_eccn++;
327	}
328	ecc_code[7] |= 0x0f;	/* set the last four bits (not used) */
329}
330
331/*
332 * rtc_from4_correct_data - hardware specific code to correct data using ECC code
333 * @mtd:	MTD device structure
334 * @buf:	buffer containing the data to generate ECC codes
335 * @ecc1	ECC codes read
336 * @ecc2	ECC codes calculated
337 *
338 * The FPGA tells us fast, if there's an error or not. If no, we go back happy
339 * else we read the ecc results from the fpga and call the rs library to decode
340 * and hopefully correct the error.
341 *
342 */
343static int rtc_from4_correct_data(struct mtd_info *mtd, const u_char *buf, u_char *ecc1, u_char *ecc2)
344{
345	int i, j, res;
346	unsigned short status;
347	uint16_t par[6], syn[6];
348	uint8_t ecc[8];
349	volatile unsigned short *rs_ecc;
350
351	status = *((volatile unsigned short *)(rtc_from4_fio_base + RTC_FROM4_RS_ECC_CHK));
352
353	if (!(status & RTC_FROM4_RS_ECC_CHK_ERROR)) {
354		return 0;
355	}
356
357	/* Read the syndrom pattern from the FPGA and correct the bitorder */
358	rs_ecc = (volatile unsigned short *)(rtc_from4_fio_base + RTC_FROM4_RS_ECC);
359	for (i = 0; i < 8; i++) {
360		ecc[i] = bitrev8(*rs_ecc);
361		rs_ecc++;
362	}
363
364	/* convert into 6 10bit syndrome fields */
365	par[5] = rs_decoder->index_of[(((uint16_t) ecc[0] >> 0) & 0x0ff) | (((uint16_t) ecc[1] << 8) & 0x300)];
366	par[4] = rs_decoder->index_of[(((uint16_t) ecc[1] >> 2) & 0x03f) | (((uint16_t) ecc[2] << 6) & 0x3c0)];
367	par[3] = rs_decoder->index_of[(((uint16_t) ecc[2] >> 4) & 0x00f) | (((uint16_t) ecc[3] << 4) & 0x3f0)];
368	par[2] = rs_decoder->index_of[(((uint16_t) ecc[3] >> 6) & 0x003) | (((uint16_t) ecc[4] << 2) & 0x3fc)];
369	par[1] = rs_decoder->index_of[(((uint16_t) ecc[5] >> 0) & 0x0ff) | (((uint16_t) ecc[6] << 8) & 0x300)];
370	par[0] = (((uint16_t) ecc[6] >> 2) & 0x03f) | (((uint16_t) ecc[7] << 6) & 0x3c0);
371
372	/* Convert to computable syndrome */
373	for (i = 0; i < 6; i++) {
374		syn[i] = par[0];
375		for (j = 1; j < 6; j++)
376			if (par[j] != rs_decoder->nn)
377				syn[i] ^= rs_decoder->alpha_to[rs_modnn(rs_decoder, par[j] + i * j)];
378
379		/* Convert to index form */
380		syn[i] = rs_decoder->index_of[syn[i]];
381	}
382
383	/* Let the library code do its magic. */
384	res = decode_rs8(rs_decoder, (uint8_t *) buf, par, 512, syn, 0, NULL, 0xff, NULL);
385	if (res > 0) {
386		DEBUG(MTD_DEBUG_LEVEL0, "rtc_from4_correct_data: " "ECC corrected %d errors on read\n", res);
387	}
388	return res;
389}
390
391/**
392 * rtc_from4_errstat - perform additional error status checks
393 * @mtd:	MTD device structure
394 * @this:	NAND chip structure
395 * @state:	state or the operation
396 * @status:	status code returned from read status
397 * @page:	startpage inside the chip, must be called with (page & this->pagemask)
398 *
399 * Perform additional error status checks on erase and write failures
400 * to determine if errors are correctable.  For this device, correctable
401 * 1-bit errors on erase and write are considered acceptable.
402 *
403 * note: see pages 34..37 of data sheet for details.
404 *
405 */
406static int rtc_from4_errstat(struct mtd_info *mtd, struct nand_chip *this,
407			     int state, int status, int page)
408{
409	int er_stat = 0;
410	int rtn, retlen;
411	size_t len;
412	uint8_t *buf;
413	int i;
414
415	this->cmdfunc(mtd, NAND_CMD_STATUS_CLEAR, -1, -1);
416
417	if (state == FL_ERASING) {
418
419		for (i = 0; i < 4; i++) {
420			if (!(status & 1 << (i + 1)))
421				continue;
422			this->cmdfunc(mtd, (NAND_CMD_STATUS_ERROR + i + 1),
423				      -1, -1);
424			rtn = this->read_byte(mtd);
425			this->cmdfunc(mtd, NAND_CMD_STATUS_RESET, -1, -1);
426
427			/* err_ecc_not_avail */
428			if (!(rtn & ERR_STAT_ECC_AVAILABLE))
429				er_stat |= 1 << (i + 1);
430		}
431
432	} else if (state == FL_WRITING) {
433
434		unsigned long corrected = mtd->ecc_stats.corrected;
435
436		/* single bank write logic */
437		this->cmdfunc(mtd, NAND_CMD_STATUS_ERROR, -1, -1);
438		rtn = this->read_byte(mtd);
439		this->cmdfunc(mtd, NAND_CMD_STATUS_RESET, -1, -1);
440
441		if (!(rtn & ERR_STAT_ECC_AVAILABLE)) {
442			/* err_ecc_not_avail */
443			er_stat |= 1 << 1;
444			goto out;
445		}
446
447		len = mtd->writesize;
448		buf = kmalloc(len, GFP_KERNEL);
449		if (!buf) {
450			printk(KERN_ERR "rtc_from4_errstat: Out of memory!\n");
451			er_stat = 1;
452			goto out;
453		}
454
455		/* recovery read */
456		rtn = nand_do_read(mtd, page, len, &retlen, buf);
457
458		/* if read failed or > 1-bit error corrected */
459		if (rtn || (mtd->ecc_stats.corrected - corrected) > 1)
460			er_stat |= 1 << 1;
461		kfree(buf);
462	}
463
464	rtn = status;
465	if (er_stat == 0) {	/* if ECC is available   */
466		rtn = (status & ~NAND_STATUS_FAIL);	/*   clear the error bit */
467	}
468
469	return rtn;
470}
471#endif
472
473/*
474 * Main initialization routine
475 */
476static int __init rtc_from4_init(void)
477{
478	struct nand_chip *this;
479	unsigned short bcr1, bcr2, wcr2;
480	int i;
481
482	/* Allocate memory for MTD device structure and private data */
483	rtc_from4_mtd = kmalloc(sizeof(struct mtd_info) + sizeof(struct nand_chip), GFP_KERNEL);
484	if (!rtc_from4_mtd) {
485		printk("Unable to allocate Renesas NAND MTD device structure.\n");
486		return -ENOMEM;
487	}
488
489	/* Get pointer to private data */
490	this = (struct nand_chip *)(&rtc_from4_mtd[1]);
491
492	/* Initialize structures */
493	memset(rtc_from4_mtd, 0, sizeof(struct mtd_info));
494	memset(this, 0, sizeof(struct nand_chip));
495
496	/* Link the private data with the MTD structure */
497	rtc_from4_mtd->priv = this;
498	rtc_from4_mtd->owner = THIS_MODULE;
499
500	/* set area 5 as PCMCIA mode to clear the spec of tDH(Data hold time;9ns min) */
501	bcr1 = *SH77X9_BCR1 & ~0x0002;
502	bcr1 |= 0x0002;
503	*SH77X9_BCR1 = bcr1;
504
505	/* set */
506	bcr2 = *SH77X9_BCR2 & ~0x0c00;
507	bcr2 |= 0x0800;
508	*SH77X9_BCR2 = bcr2;
509
510	/* set area 5 wait states */
511	wcr2 = *SH77X9_WCR2 & ~0x1c00;
512	wcr2 |= 0x1c00;
513	*SH77X9_WCR2 = wcr2;
514
515	/* Set address of NAND IO lines */
516	this->IO_ADDR_R = rtc_from4_fio_base;
517	this->IO_ADDR_W = rtc_from4_fio_base;
518	/* Set address of hardware control function */
519	this->cmd_ctrl = rtc_from4_hwcontrol;
520	/* Set address of chip select function */
521	this->select_chip = rtc_from4_nand_select_chip;
522	/* command delay time (in us) */
523	this->chip_delay = 100;
524	/* return the status of the Ready/Busy line */
525	this->dev_ready = rtc_from4_nand_device_ready;
526
527#ifdef RTC_FROM4_HWECC
528	printk(KERN_INFO "rtc_from4_init: using hardware ECC detection.\n");
529
530	this->ecc.mode = NAND_ECC_HW_SYNDROME;
531	this->ecc.size = 512;
532	this->ecc.bytes = 8;
533	/* return the status of extra status and ECC checks */
534	this->errstat = rtc_from4_errstat;
535	/* set the nand_oobinfo to support FPGA H/W error detection */
536	this->ecc.layout = &rtc_from4_nand_oobinfo;
537	this->ecc.hwctl = rtc_from4_enable_hwecc;
538	this->ecc.calculate = rtc_from4_calculate_ecc;
539	this->ecc.correct = rtc_from4_correct_data;
540#else
541	printk(KERN_INFO "rtc_from4_init: using software ECC detection.\n");
542
543	this->ecc.mode = NAND_ECC_SOFT;
544#endif
545
546	/* set the bad block tables to support debugging */
547	this->bbt_td = &rtc_from4_bbt_main_descr;
548	this->bbt_md = &rtc_from4_bbt_mirror_descr;
549
550	/* Scan to find existence of the device */
551	if (nand_scan(rtc_from4_mtd, RTC_FROM4_MAX_CHIPS)) {
552		kfree(rtc_from4_mtd);
553		return -ENXIO;
554	}
555
556	/* Perform 'device recovery' for each chip in case there was a power loss. */
557	for (i = 0; i < this->numchips; i++) {
558		deplete(rtc_from4_mtd, i);
559	}
560
561#if RTC_FROM4_NO_VIRTBLOCKS
562	/* use a smaller erase block to minimize wasted space when a block is bad */
563	/* note: this uses eight times as much RAM as using the default and makes */
564	/*       mounts take four times as long. */
565	rtc_from4_mtd->flags |= MTD_NO_VIRTBLOCKS;
566#endif
567
568	/* Register the partitions */
569	add_mtd_partitions(rtc_from4_mtd, partition_info, NUM_PARTITIONS);
570
571#ifdef RTC_FROM4_HWECC
572	/* We could create the decoder on demand, if memory is a concern.
573	 * This way we have it handy, if an error happens
574	 *
575	 * Symbolsize is 10 (bits)
576	 * Primitve polynomial is x^10+x^3+1
577	 * first consecutive root is 0
578	 * primitve element to generate roots = 1
579	 * generator polinomial degree = 6
580	 */
581	rs_decoder = init_rs(10, 0x409, 0, 1, 6);
582	if (!rs_decoder) {
583		printk(KERN_ERR "Could not create a RS decoder\n");
584		nand_release(rtc_from4_mtd);
585		kfree(rtc_from4_mtd);
586		return -ENOMEM;
587	}
588#endif
589	/* Return happy */
590	return 0;
591}
592
593module_init(rtc_from4_init);
594
595/*
596 * Clean up routine
597 */
598static void __exit rtc_from4_cleanup(void)
599{
600	/* Release resource, unregister partitions */
601	nand_release(rtc_from4_mtd);
602
603	/* Free the MTD device structure */
604	kfree(rtc_from4_mtd);
605
606#ifdef RTC_FROM4_HWECC
607	/* Free the reed solomon resources */
608	if (rs_decoder) {
609		free_rs(rs_decoder);
610	}
611#endif
612}
613
614module_exit(rtc_from4_cleanup);
615
616MODULE_LICENSE("GPL");
617MODULE_AUTHOR("d.marlin <dmarlin@redhat.com");
618MODULE_DESCRIPTION("Board-specific glue layer for AG-AND flash on Renesas FROM_BOARD4");
619