s3c2410.c revision a4f957f16d41b9ff944dddd84c4892496a129f68
1/* linux/drivers/mtd/nand/s3c2410.c
2 *
3 * Copyright (c) 2004,2005 Simtec Electronics
4 *	http://www.simtec.co.uk/products/SWLINUX/
5 *	Ben Dooks <ben@simtec.co.uk>
6 *
7 * Samsung S3C2410/S3C240 NAND driver
8 *
9 * Changelog:
10 *	21-Sep-2004  BJD  Initial version
11 *	23-Sep-2004  BJD  Mulitple device support
12 *	28-Sep-2004  BJD  Fixed ECC placement for Hardware mode
13 *	12-Oct-2004  BJD  Fixed errors in use of platform data
14 *	18-Feb-2005  BJD  Fix sparse errors
15 *	14-Mar-2005  BJD  Applied tglx's code reduction patch
16 *	02-May-2005  BJD  Fixed s3c2440 support
17 *	02-May-2005  BJD  Reduced hwcontrol decode
18 *	20-Jun-2005  BJD  Updated s3c2440 support, fixed timing bug
19 *
20 * $Id: s3c2410.c,v 1.13 2005/06/20 11:48:21 bjd Exp $
21 *
22 * This program is free software; you can redistribute it and/or modify
23 * it under the terms of the GNU General Public License as published by
24 * the Free Software Foundation; either version 2 of the License, or
25 * (at your option) any later version.
26 *
27 * This program is distributed in the hope that it will be useful,
28 * but WITHOUT ANY WARRANTY; without even the implied warranty of
29 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
30 * GNU General Public License for more details.
31 *
32 * You should have received a copy of the GNU General Public License
33 * along with this program; if not, write to the Free Software
34 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
35*/
36
37#include <config/mtd/nand/s3c2410/hwecc.h>
38#include <config/mtd/nand/s3c2410/debug.h>
39
40#ifdef CONFIG_MTD_NAND_S3C2410_DEBUG
41#define DEBUG
42#endif
43
44#include <linux/module.h>
45#include <linux/types.h>
46#include <linux/init.h>
47#include <linux/kernel.h>
48#include <linux/string.h>
49#include <linux/ioport.h>
50#include <linux/device.h>
51#include <linux/delay.h>
52#include <linux/err.h>
53
54#include <linux/mtd/mtd.h>
55#include <linux/mtd/nand.h>
56#include <linux/mtd/nand_ecc.h>
57#include <linux/mtd/partitions.h>
58
59#include <asm/io.h>
60#include <asm/mach-types.h>
61#include <asm/hardware/clock.h>
62
63#include <asm/arch/regs-nand.h>
64#include <asm/arch/nand.h>
65
66#define PFX "s3c2410-nand: "
67
68#ifdef CONFIG_MTD_NAND_S3C2410_HWECC
69static int hardware_ecc = 1;
70#else
71static int hardware_ecc = 0;
72#endif
73
74/* new oob placement block for use with hardware ecc generation
75 */
76
77static struct nand_oobinfo nand_hw_eccoob = {
78	.useecc		= MTD_NANDECC_AUTOPLACE,
79	.eccbytes	= 3,
80	.eccpos		= {0, 1, 2 },
81	.oobfree	= { {8, 8} }
82};
83
84/* controller and mtd information */
85
86struct s3c2410_nand_info;
87
88struct s3c2410_nand_mtd {
89	struct mtd_info			mtd;
90	struct nand_chip		chip;
91	struct s3c2410_nand_set		*set;
92	struct s3c2410_nand_info	*info;
93	int				scan_res;
94};
95
96/* overview of the s3c2410 nand state */
97
98struct s3c2410_nand_info {
99	/* mtd info */
100	struct nand_hw_control		controller;
101	struct s3c2410_nand_mtd		*mtds;
102	struct s3c2410_platform_nand	*platform;
103
104	/* device info */
105	struct device			*device;
106	struct resource			*area;
107	struct clk			*clk;
108	void __iomem			*regs;
109	int				mtd_count;
110
111	unsigned char			is_s3c2440;
112};
113
114/* conversion functions */
115
116static struct s3c2410_nand_mtd *s3c2410_nand_mtd_toours(struct mtd_info *mtd)
117{
118	return container_of(mtd, struct s3c2410_nand_mtd, mtd);
119}
120
121static struct s3c2410_nand_info *s3c2410_nand_mtd_toinfo(struct mtd_info *mtd)
122{
123	return s3c2410_nand_mtd_toours(mtd)->info;
124}
125
126static struct s3c2410_nand_info *to_nand_info(struct device *dev)
127{
128	return dev_get_drvdata(dev);
129}
130
131static struct s3c2410_platform_nand *to_nand_plat(struct device *dev)
132{
133	return dev->platform_data;
134}
135
136/* timing calculations */
137
138#define NS_IN_KHZ 10000000
139
140static int s3c2410_nand_calc_rate(int wanted, unsigned long clk, int max)
141{
142	int result;
143
144	result = (wanted * NS_IN_KHZ) / clk;
145	result++;
146
147	pr_debug("result %d from %ld, %d\n", result, clk, wanted);
148
149	if (result > max) {
150		printk("%d ns is too big for current clock rate %ld\n",
151		       wanted, clk);
152		return -1;
153	}
154
155	if (result < 1)
156		result = 1;
157
158	return result;
159}
160
161#define to_ns(ticks,clk) (((clk) * (ticks)) / NS_IN_KHZ)
162
163/* controller setup */
164
165static int s3c2410_nand_inithw(struct s3c2410_nand_info *info,
166			       struct device *dev)
167{
168	struct s3c2410_platform_nand *plat = to_nand_plat(dev);
169	unsigned int tacls, twrph0, twrph1;
170	unsigned long clkrate = clk_get_rate(info->clk);
171	unsigned long cfg;
172
173	/* calculate the timing information for the controller */
174
175	if (plat != NULL) {
176		tacls  = s3c2410_nand_calc_rate(plat->tacls, clkrate, 4);
177		twrph0 = s3c2410_nand_calc_rate(plat->twrph0, clkrate, 8);
178		twrph1 = s3c2410_nand_calc_rate(plat->twrph1, clkrate, 8);
179	} else {
180		/* default timings */
181		tacls = 4;
182		twrph0 = 8;
183		twrph1 = 8;
184	}
185
186	if (tacls < 0 || twrph0 < 0 || twrph1 < 0) {
187		printk(KERN_ERR PFX "cannot get timings suitable for board\n");
188		return -EINVAL;
189	}
190
191	printk(KERN_INFO PFX "timing: Tacls %ldns, Twrph0 %ldns, Twrph1 %ldns\n",
192	       to_ns(tacls, clkrate),
193	       to_ns(twrph0, clkrate),
194	       to_ns(twrph1, clkrate));
195
196	if (!info->is_s3c2440) {
197		cfg  = S3C2410_NFCONF_EN;
198		cfg |= S3C2410_NFCONF_TACLS(tacls-1);
199		cfg |= S3C2410_NFCONF_TWRPH0(twrph0-1);
200		cfg |= S3C2410_NFCONF_TWRPH1(twrph1-1);
201	} else {
202		cfg   = S3C2440_NFCONF_TACLS(tacls-1);
203		cfg  |= S3C2440_NFCONF_TWRPH0(twrph0-1);
204		cfg  |= S3C2440_NFCONF_TWRPH1(twrph1-1);
205	}
206
207	pr_debug(PFX "NF_CONF is 0x%lx\n", cfg);
208
209	writel(cfg, info->regs + S3C2410_NFCONF);
210	return 0;
211}
212
213/* select chip */
214
215static void s3c2410_nand_select_chip(struct mtd_info *mtd, int chip)
216{
217	struct s3c2410_nand_info *info;
218	struct s3c2410_nand_mtd *nmtd;
219	struct nand_chip *this = mtd->priv;
220	void __iomem *reg;
221	unsigned long cur;
222	unsigned long bit;
223
224	nmtd = this->priv;
225	info = nmtd->info;
226
227	bit = (info->is_s3c2440) ? S3C2440_NFCONT_nFCE : S3C2410_NFCONF_nFCE;
228	reg = info->regs+((info->is_s3c2440) ? S3C2440_NFCONT:S3C2410_NFCONF);
229
230	cur = readl(reg);
231
232	if (chip == -1) {
233		cur |= bit;
234	} else {
235		if (chip > nmtd->set->nr_chips) {
236			printk(KERN_ERR PFX "chip %d out of range\n", chip);
237			return;
238		}
239
240		if (info->platform != NULL) {
241			if (info->platform->select_chip != NULL)
242				(info->platform->select_chip)(nmtd->set, chip);
243		}
244
245		cur &= ~bit;
246	}
247
248	writel(cur, reg);
249}
250
251/* command and control functions
252 *
253 * Note, these all use tglx's method of changing the IO_ADDR_W field
254 * to make the code simpler, and use the nand layer's code to issue the
255 * command and address sequences via the proper IO ports.
256 *
257*/
258
259static void s3c2410_nand_hwcontrol(struct mtd_info *mtd, int cmd)
260{
261	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
262	struct nand_chip *chip = mtd->priv;
263
264	switch (cmd) {
265	case NAND_CTL_SETNCE:
266	case NAND_CTL_CLRNCE:
267		printk(KERN_ERR "%s: called for NCE\n", __FUNCTION__);
268		break;
269
270	case NAND_CTL_SETCLE:
271		chip->IO_ADDR_W = info->regs + S3C2410_NFCMD;
272		break;
273
274	case NAND_CTL_SETALE:
275		chip->IO_ADDR_W = info->regs + S3C2410_NFADDR;
276		break;
277
278		/* NAND_CTL_CLRCLE: */
279		/* NAND_CTL_CLRALE: */
280	default:
281		chip->IO_ADDR_W = info->regs + S3C2410_NFDATA;
282		break;
283	}
284}
285
286/* command and control functions */
287
288static void s3c2440_nand_hwcontrol(struct mtd_info *mtd, int cmd)
289{
290	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
291	struct nand_chip *chip = mtd->priv;
292
293	switch (cmd) {
294	case NAND_CTL_SETNCE:
295	case NAND_CTL_CLRNCE:
296		printk(KERN_ERR "%s: called for NCE\n", __FUNCTION__);
297		break;
298
299	case NAND_CTL_SETCLE:
300		chip->IO_ADDR_W = info->regs + S3C2440_NFCMD;
301		break;
302
303	case NAND_CTL_SETALE:
304		chip->IO_ADDR_W = info->regs + S3C2440_NFADDR;
305		break;
306
307		/* NAND_CTL_CLRCLE: */
308		/* NAND_CTL_CLRALE: */
309	default:
310		chip->IO_ADDR_W = info->regs + S3C2440_NFDATA;
311		break;
312	}
313}
314
315/* s3c2410_nand_devready()
316 *
317 * returns 0 if the nand is busy, 1 if it is ready
318*/
319
320static int s3c2410_nand_devready(struct mtd_info *mtd)
321{
322	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
323
324	if (info->is_s3c2440)
325		return readb(info->regs + S3C2440_NFSTAT) & S3C2440_NFSTAT_READY;
326	return readb(info->regs + S3C2410_NFSTAT) & S3C2410_NFSTAT_BUSY;
327}
328
329
330/* ECC handling functions */
331
332static int s3c2410_nand_correct_data(struct mtd_info *mtd, u_char *dat,
333				     u_char *read_ecc, u_char *calc_ecc)
334{
335	pr_debug("s3c2410_nand_correct_data(%p,%p,%p,%p)\n",
336		 mtd, dat, read_ecc, calc_ecc);
337
338	pr_debug("eccs: read %02x,%02x,%02x vs calc %02x,%02x,%02x\n",
339		 read_ecc[0], read_ecc[1], read_ecc[2],
340		 calc_ecc[0], calc_ecc[1], calc_ecc[2]);
341
342	if (read_ecc[0] == calc_ecc[0] &&
343	    read_ecc[1] == calc_ecc[1] &&
344	    read_ecc[2] == calc_ecc[2])
345		return 0;
346
347	/* we curently have no method for correcting the error */
348
349	return -1;
350}
351
352/* ECC functions
353 *
354 * These allow the s3c2410 and s3c2440 to use the controller's ECC
355 * generator block to ECC the data as it passes through]
356*/
357
358static void s3c2410_nand_enable_hwecc(struct mtd_info *mtd, int mode)
359{
360	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
361	unsigned long ctrl;
362
363	ctrl = readl(info->regs + S3C2410_NFCONF);
364	ctrl |= S3C2410_NFCONF_INITECC;
365	writel(ctrl, info->regs + S3C2410_NFCONF);
366}
367
368static void s3c2440_nand_enable_hwecc(struct mtd_info *mtd, int mode)
369{
370	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
371	unsigned long ctrl;
372
373	ctrl = readl(info->regs + S3C2440_NFCONT);
374	writel(ctrl | S3C2440_NFCONT_INITECC, info->regs + S3C2440_NFCONT);
375}
376
377static int s3c2410_nand_calculate_ecc(struct mtd_info *mtd,
378				      const u_char *dat, u_char *ecc_code)
379{
380	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
381
382	ecc_code[0] = readb(info->regs + S3C2410_NFECC + 0);
383	ecc_code[1] = readb(info->regs + S3C2410_NFECC + 1);
384	ecc_code[2] = readb(info->regs + S3C2410_NFECC + 2);
385
386	pr_debug("calculate_ecc: returning ecc %02x,%02x,%02x\n",
387		 ecc_code[0], ecc_code[1], ecc_code[2]);
388
389	return 0;
390}
391
392
393static int s3c2440_nand_calculate_ecc(struct mtd_info *mtd,
394				      const u_char *dat, u_char *ecc_code)
395{
396	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
397	unsigned long ecc = readl(info->regs + S3C2440_NFMECC0);
398
399	ecc_code[0] = ecc;
400	ecc_code[1] = ecc >> 8;
401	ecc_code[2] = ecc >> 16;
402
403	pr_debug("calculate_ecc: returning ecc %02x,%02x,%02x\n",
404		 ecc_code[0], ecc_code[1], ecc_code[2]);
405
406	return 0;
407}
408
409
410/* over-ride the standard functions for a little more speed. We can
411 * use read/write block to move the data buffers to/from the controller
412*/
413
414static void s3c2410_nand_read_buf(struct mtd_info *mtd, u_char *buf, int len)
415{
416	struct nand_chip *this = mtd->priv;
417	readsb(this->IO_ADDR_R, buf, len);
418}
419
420static void s3c2410_nand_write_buf(struct mtd_info *mtd,
421				   const u_char *buf, int len)
422{
423	struct nand_chip *this = mtd->priv;
424	writesb(this->IO_ADDR_W, buf, len);
425}
426
427/* device management functions */
428
429static int s3c2410_nand_remove(struct device *dev)
430{
431	struct s3c2410_nand_info *info = to_nand_info(dev);
432
433	dev_set_drvdata(dev, NULL);
434
435	if (info == NULL)
436		return 0;
437
438	/* first thing we need to do is release all our mtds
439	 * and their partitions, then go through freeing the
440	 * resources used
441	 */
442
443	if (info->mtds != NULL) {
444		struct s3c2410_nand_mtd *ptr = info->mtds;
445		int mtdno;
446
447		for (mtdno = 0; mtdno < info->mtd_count; mtdno++, ptr++) {
448			pr_debug("releasing mtd %d (%p)\n", mtdno, ptr);
449			nand_release(&ptr->mtd);
450		}
451
452		kfree(info->mtds);
453	}
454
455	/* free the common resources */
456
457	if (info->clk != NULL && !IS_ERR(info->clk)) {
458		clk_disable(info->clk);
459		clk_unuse(info->clk);
460		clk_put(info->clk);
461	}
462
463	if (info->regs != NULL) {
464		iounmap(info->regs);
465		info->regs = NULL;
466	}
467
468	if (info->area != NULL) {
469		release_resource(info->area);
470		kfree(info->area);
471		info->area = NULL;
472	}
473
474	kfree(info);
475
476	return 0;
477}
478
479#ifdef CONFIG_MTD_PARTITIONS
480static int s3c2410_nand_add_partition(struct s3c2410_nand_info *info,
481				      struct s3c2410_nand_mtd *mtd,
482				      struct s3c2410_nand_set *set)
483{
484	if (set == NULL)
485		return add_mtd_device(&mtd->mtd);
486
487	if (set->nr_partitions > 0 && set->partitions != NULL) {
488		return add_mtd_partitions(&mtd->mtd,
489					  set->partitions,
490					  set->nr_partitions);
491	}
492
493	return add_mtd_device(&mtd->mtd);
494}
495#else
496static int s3c2410_nand_add_partition(struct s3c2410_nand_info *info,
497				      struct s3c2410_nand_mtd *mtd,
498				      struct s3c2410_nand_set *set)
499{
500	return add_mtd_device(&mtd->mtd);
501}
502#endif
503
504/* s3c2410_nand_init_chip
505 *
506 * init a single instance of an chip
507*/
508
509static void s3c2410_nand_init_chip(struct s3c2410_nand_info *info,
510				   struct s3c2410_nand_mtd *nmtd,
511				   struct s3c2410_nand_set *set)
512{
513	struct nand_chip *chip = &nmtd->chip;
514
515	chip->IO_ADDR_R	   = info->regs + S3C2410_NFDATA;
516	chip->IO_ADDR_W    = info->regs + S3C2410_NFDATA;
517	chip->hwcontrol    = s3c2410_nand_hwcontrol;
518	chip->dev_ready    = s3c2410_nand_devready;
519	chip->write_buf    = s3c2410_nand_write_buf;
520	chip->read_buf     = s3c2410_nand_read_buf;
521	chip->select_chip  = s3c2410_nand_select_chip;
522	chip->chip_delay   = 50;
523	chip->priv	   = nmtd;
524	chip->options	   = 0;
525	chip->controller   = &info->controller;
526
527	if (info->is_s3c2440) {
528		chip->IO_ADDR_R	 = info->regs + S3C2440_NFDATA;
529		chip->IO_ADDR_W  = info->regs + S3C2440_NFDATA;
530		chip->hwcontrol  = s3c2440_nand_hwcontrol;
531	}
532
533	nmtd->info	   = info;
534	nmtd->mtd.priv	   = chip;
535	nmtd->set	   = set;
536
537	if (hardware_ecc) {
538		chip->correct_data  = s3c2410_nand_correct_data;
539		chip->enable_hwecc  = s3c2410_nand_enable_hwecc;
540		chip->calculate_ecc = s3c2410_nand_calculate_ecc;
541		chip->eccmode	    = NAND_ECC_HW3_512;
542		chip->autooob       = &nand_hw_eccoob;
543
544		if (info->is_s3c2440) {
545			chip->enable_hwecc  = s3c2440_nand_enable_hwecc;
546			chip->calculate_ecc = s3c2440_nand_calculate_ecc;
547		}
548	} else {
549		chip->eccmode	    = NAND_ECC_SOFT;
550	}
551}
552
553/* s3c2410_nand_probe
554 *
555 * called by device layer when it finds a device matching
556 * one our driver can handled. This code checks to see if
557 * it can allocate all necessary resources then calls the
558 * nand layer to look for devices
559*/
560
561static int s3c24xx_nand_probe(struct device *dev, int is_s3c2440)
562{
563	struct platform_device *pdev = to_platform_device(dev);
564	struct s3c2410_platform_nand *plat = to_nand_plat(dev);
565	struct s3c2410_nand_info *info;
566	struct s3c2410_nand_mtd *nmtd;
567	struct s3c2410_nand_set *sets;
568	struct resource *res;
569	int err = 0;
570	int size;
571	int nr_sets;
572	int setno;
573
574	pr_debug("s3c2410_nand_probe(%p)\n", dev);
575
576	info = kmalloc(sizeof(*info), GFP_KERNEL);
577	if (info == NULL) {
578		printk(KERN_ERR PFX "no memory for flash info\n");
579		err = -ENOMEM;
580		goto exit_error;
581	}
582
583	memzero(info, sizeof(*info));
584	dev_set_drvdata(dev, info);
585
586	spin_lock_init(&info->controller.lock);
587	init_waitqueue_head(&info->controller.wq);
588
589	/* get the clock source and enable it */
590
591	info->clk = clk_get(dev, "nand");
592	if (IS_ERR(info->clk)) {
593		printk(KERN_ERR PFX "failed to get clock");
594		err = -ENOENT;
595		goto exit_error;
596	}
597
598	clk_use(info->clk);
599	clk_enable(info->clk);
600
601	/* allocate and map the resource */
602
603	/* currently we assume we have the one resource */
604	res  = pdev->resource;
605	size = res->end - res->start + 1;
606
607	info->area = request_mem_region(res->start, size, pdev->name);
608
609	if (info->area == NULL) {
610		printk(KERN_ERR PFX "cannot reserve register region\n");
611		err = -ENOENT;
612		goto exit_error;
613	}
614
615	info->device     = dev;
616	info->platform   = plat;
617	info->regs       = ioremap(res->start, size);
618	info->is_s3c2440 = is_s3c2440;
619
620	if (info->regs == NULL) {
621		printk(KERN_ERR PFX "cannot reserve register region\n");
622		err = -EIO;
623		goto exit_error;
624	}
625
626	printk(KERN_INFO PFX "mapped registers at %p\n", info->regs);
627
628	/* initialise the hardware */
629
630	err = s3c2410_nand_inithw(info, dev);
631	if (err != 0)
632		goto exit_error;
633
634	sets = (plat != NULL) ? plat->sets : NULL;
635	nr_sets = (plat != NULL) ? plat->nr_sets : 1;
636
637	info->mtd_count = nr_sets;
638
639	/* allocate our information */
640
641	size = nr_sets * sizeof(*info->mtds);
642	info->mtds = kmalloc(size, GFP_KERNEL);
643	if (info->mtds == NULL) {
644		printk(KERN_ERR PFX "failed to allocate mtd storage\n");
645		err = -ENOMEM;
646		goto exit_error;
647	}
648
649	memzero(info->mtds, size);
650
651	/* initialise all possible chips */
652
653	nmtd = info->mtds;
654
655	for (setno = 0; setno < nr_sets; setno++, nmtd++) {
656		pr_debug("initialising set %d (%p, info %p)\n",
657			 setno, nmtd, info);
658
659		s3c2410_nand_init_chip(info, nmtd, sets);
660
661		nmtd->scan_res = nand_scan(&nmtd->mtd,
662					   (sets) ? sets->nr_chips : 1);
663
664		if (nmtd->scan_res == 0) {
665			s3c2410_nand_add_partition(info, nmtd, sets);
666		}
667
668		if (sets != NULL)
669			sets++;
670	}
671
672	pr_debug("initialised ok\n");
673	return 0;
674
675 exit_error:
676	s3c2410_nand_remove(dev);
677
678	if (err == 0)
679		err = -EINVAL;
680	return err;
681}
682
683/* driver device registration */
684
685static int s3c2410_nand_probe(struct device *dev)
686{
687	return s3c24xx_nand_probe(dev, 0);
688}
689
690static int s3c2440_nand_probe(struct device *dev)
691{
692	return s3c24xx_nand_probe(dev, 1);
693}
694
695static struct device_driver s3c2410_nand_driver = {
696	.name		= "s3c2410-nand",
697	.bus		= &platform_bus_type,
698	.probe		= s3c2410_nand_probe,
699	.remove		= s3c2410_nand_remove,
700};
701
702static struct device_driver s3c2440_nand_driver = {
703	.name		= "s3c2440-nand",
704	.bus		= &platform_bus_type,
705	.probe		= s3c2440_nand_probe,
706	.remove		= s3c2410_nand_remove,
707};
708
709static int __init s3c2410_nand_init(void)
710{
711	printk("S3C24XX NAND Driver, (c) 2004 Simtec Electronics\n");
712
713	driver_register(&s3c2440_nand_driver);
714	return driver_register(&s3c2410_nand_driver);
715}
716
717static void __exit s3c2410_nand_exit(void)
718{
719	driver_unregister(&s3c2440_nand_driver);
720	driver_unregister(&s3c2410_nand_driver);
721}
722
723module_init(s3c2410_nand_init);
724module_exit(s3c2410_nand_exit);
725
726MODULE_LICENSE("GPL");
727MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
728MODULE_DESCRIPTION("S3C24XX MTD NAND driver");
729