drivers/mtd/nand/alauda.c - android_kernel_htc_msm8960 - Gitiles

 /*
  * MTD driver for Alauda chips
  *
  * Copyright (C) 2007 Joern Engel <joern@logfs.org>
  *
  * Based on drivers/usb/usb-skeleton.c which is:
  * Copyright (C) 2001-2004 Greg Kroah-Hartman (greg@kroah.com)
  * and on drivers/usb/storage/alauda.c, which is:
  *   (c) 2005 Daniel Drake <dsd@gentoo.org>
  *
  * Idea and initial work by Arnd Bergmann <arnd@arndb.de>
  */
 #include <linux/kernel.h>
 #include <linux/errno.h>
 #include <linux/init.h>
 #include <linux/slab.h>
 #include <linux/module.h>
 #include <linux/kref.h>
 #include <linux/usb.h>
 #include <linux/mutex.h>
 #include <linux/mtd/mtd.h>
 #include <linux/mtd/nand_ecc.h>

 /* Control commands */
 #define ALAUDA_GET_XD_MEDIA_STATUS	0x08
 #define ALAUDA_ACK_XD_MEDIA_CHANGE	0x0a
 #define ALAUDA_GET_XD_MEDIA_SIG		0x86

 /* Common prefix */
 #define ALAUDA_BULK_CMD			0x40

 /* The two ports */
 #define ALAUDA_PORT_XD			0x00
 #define ALAUDA_PORT_SM			0x01

 /* Bulk commands */
 #define ALAUDA_BULK_READ_PAGE		0x84
 #define ALAUDA_BULK_READ_OOB		0x85 /* don't use, there's a chip bug */
 #define ALAUDA_BULK_READ_BLOCK		0x94
 #define ALAUDA_BULK_ERASE_BLOCK		0xa3
 #define ALAUDA_BULK_WRITE_PAGE		0xa4
 #define ALAUDA_BULK_WRITE_BLOCK		0xb4
 #define ALAUDA_BULK_RESET_MEDIA		0xe0

 /* Address shifting */
 #define PBA_LO(pba) ((pba & 0xF) << 5)
 #define PBA_HI(pba) (pba >> 3)
 #define PBA_ZONE(pba) (pba >> 11)

 #define TIMEOUT HZ

 static struct usb_device_id alauda_table [] = {
 	{ USB_DEVICE(0x0584, 0x0008) },	/* Fujifilm DPC-R1 */
 	{ USB_DEVICE(0x07b4, 0x010a) },	/* Olympus MAUSB-10 */
 	{ }
 };
 MODULE_DEVICE_TABLE(usb, alauda_table);

 struct alauda_card {
 	u8	id;		/* id byte */
 	u8	chipshift;	/* 1<<chipshift total size */
 	u8	pageshift;	/* 1<<pageshift page size */
 	u8	blockshift;	/* 1<<blockshift block size */
 };

 struct alauda {
 	struct usb_device	*dev;
 	struct usb_interface	*interface;
 	struct mtd_info		*mtd;
 	struct alauda_card	*card;
 	struct mutex		card_mutex;
 	u32			pagemask;
 	u32			bytemask;
 	u32			blockmask;
 	unsigned int		write_out;
 	unsigned int		bulk_in;
 	unsigned int		bulk_out;
 	u8			port;
 	struct kref		kref;
 };

 static struct alauda_card alauda_card_ids[] = {
 	/* NAND flash */
 	{ 0x6e, 20, 8, 12},	/* 1 MB */
 	{ 0xe8, 20, 8, 12},	/* 1 MB */
 	{ 0xec, 20, 8, 12},	/* 1 MB */
 	{ 0x64, 21, 8, 12},	/* 2 MB */
 	{ 0xea, 21, 8, 12},	/* 2 MB */
 	{ 0x6b, 22, 9, 13},	/* 4 MB */
 	{ 0xe3, 22, 9, 13},	/* 4 MB */
 	{ 0xe5, 22, 9, 13},	/* 4 MB */
 	{ 0xe6, 23, 9, 13},	/* 8 MB */
 	{ 0x73, 24, 9, 14},	/* 16 MB */
 	{ 0x75, 25, 9, 14},	/* 32 MB */
 	{ 0x76, 26, 9, 14},	/* 64 MB */
 	{ 0x79, 27, 9, 14},	/* 128 MB */
 	{ 0x71, 28, 9, 14},	/* 256 MB */

 	/* MASK ROM */
 	{ 0x5d, 21, 9, 13},	/* 2 MB */
 	{ 0xd5, 22, 9, 13},	/* 4 MB */
 	{ 0xd6, 23, 9, 13},	/* 8 MB */
 	{ 0x57, 24, 9, 13},	/* 16 MB */
 	{ 0x58, 25, 9, 13},	/* 32 MB */
 	{ }
 };

 static struct alauda_card *get_card(u8 id)
 {
 	struct alauda_card *card;

 	for (card = alauda_card_ids; card->id; card++)
 		if (card->id == id)
 			return card;
 	return NULL;
 }

 static void alauda_delete(struct kref *kref)
 {
 	struct alauda *al = container_of(kref, struct alauda, kref);

 	if (al->mtd) {
 		del_mtd_device(al->mtd);
 		kfree(al->mtd);
 	}
 	usb_put_dev(al->dev);
 	kfree(al);
 }

 static int alauda_get_media_status(struct alauda *al, void *buf)
 {
 	int ret;

 	mutex_lock(&al->card_mutex);
 	ret = usb_control_msg(al->dev, usb_rcvctrlpipe(al->dev, 0),
 			ALAUDA_GET_XD_MEDIA_STATUS, 0xc0, 0, 1, buf, 2, HZ);
 	mutex_unlock(&al->card_mutex);
 	return ret;
 }

 static int alauda_ack_media(struct alauda *al)
 {
 	int ret;

 	mutex_lock(&al->card_mutex);
 	ret = usb_control_msg(al->dev, usb_sndctrlpipe(al->dev, 0),
 			ALAUDA_ACK_XD_MEDIA_CHANGE, 0x40, 0, 1, NULL, 0, HZ);
 	mutex_unlock(&al->card_mutex);
 	return ret;
 }

 static int alauda_get_media_signatures(struct alauda *al, void *buf)
 {
 	int ret;

 	mutex_lock(&al->card_mutex);
 	ret = usb_control_msg(al->dev, usb_rcvctrlpipe(al->dev, 0),
 			ALAUDA_GET_XD_MEDIA_SIG, 0xc0, 0, 0, buf, 4, HZ);
 	mutex_unlock(&al->card_mutex);
 	return ret;
 }

 static void alauda_reset(struct alauda *al)
 {
 	u8 command[] = {
 		ALAUDA_BULK_CMD, ALAUDA_BULK_RESET_MEDIA, 0, 0,
 		0, 0, 0, 0, al->port
 	};
 	mutex_lock(&al->card_mutex);
 	usb_bulk_msg(al->dev, al->bulk_out, command, 9, NULL, HZ);
 	mutex_unlock(&al->card_mutex);
 }

 static void correct_data(void *buf, void *read_ecc,
 		int *corrected, int *uncorrected)
 {
 	u8 calc_ecc[3];
 	int err;

 	nand_calculate_ecc(NULL, buf, calc_ecc);
 	err = nand_correct_data(NULL, buf, read_ecc, calc_ecc);
 	if (err) {
 		if (err > 0)
 			(*corrected)++;
 		else
 			(*uncorrected)++;
 	}
 }

 struct alauda_sg_request {
 	struct urb *urb[3];
 	struct completion comp;
 };

 static void alauda_complete(struct urb *urb)
 {
 	struct completion *comp = urb->context;

 	if (comp)
 		complete(comp);
 }

 static int __alauda_read_page(struct mtd_info *mtd, loff_t from, void *buf,
 		void *oob)
 {
 	struct alauda_sg_request sg;
 	struct alauda *al = mtd->priv;
 	u32 pba = from >> al->card->blockshift;
 	u32 page = (from >> al->card->pageshift) & al->pagemask;
 	u8 command[] = {
 		ALAUDA_BULK_CMD, ALAUDA_BULK_READ_PAGE, PBA_HI(pba),
 		PBA_ZONE(pba), 0, PBA_LO(pba) + page, 1, 0, al->port
 	};
 	int i, err;

 	for (i=0; i<3; i++)
 		sg.urb[i] = NULL;

 	err = -ENOMEM;
 	for (i=0; i<3; i++) {
 		sg.urb[i] = usb_alloc_urb(0, GFP_NOIO);
 		if (!sg.urb[i])
 			goto out;
 	}
 	init_completion(&sg.comp);
 	usb_fill_bulk_urb(sg.urb[0], al->dev, al->bulk_out, command, 9,
 			alauda_complete, NULL);
 	usb_fill_bulk_urb(sg.urb[1], al->dev, al->bulk_in, buf, mtd->writesize,
 			alauda_complete, NULL);
 	usb_fill_bulk_urb(sg.urb[2], al->dev, al->bulk_in, oob, 16,
 			alauda_complete, &sg.comp);

 	mutex_lock(&al->card_mutex);
 	for (i=0; i<3; i++) {
 		err = usb_submit_urb(sg.urb[i], GFP_NOIO);
 		if (err)
 			goto cancel;
 	}
 	if (!wait_for_completion_timeout(&sg.comp, TIMEOUT)) {
 		err = -ETIMEDOUT;
 cancel:
 		for (i=0; i<3; i++) {
 			usb_kill_urb(sg.urb[i]);
 		}
 	}
 	mutex_unlock(&al->card_mutex);

 out:
 	usb_free_urb(sg.urb[0]);
 	usb_free_urb(sg.urb[1]);
 	usb_free_urb(sg.urb[2]);
 	return err;
 }

 static int alauda_read_page(struct mtd_info *mtd, loff_t from,
 		void *buf, u8 *oob, int *corrected, int *uncorrected)
 {
 	int err;

 	err = __alauda_read_page(mtd, from, buf, oob);
 	if (err)
 		return err;
 	correct_data(buf, oob+13, corrected, uncorrected);
 	correct_data(buf+256, oob+8, corrected, uncorrected);
 	return 0;
 }

 static int alauda_write_page(struct mtd_info *mtd, loff_t to, void *buf,
 		void *oob)
 {
 	struct alauda_sg_request sg;
 	struct alauda *al = mtd->priv;
 	u32 pba = to >> al->card->blockshift;
 	u32 page = (to >> al->card->pageshift) & al->pagemask;
 	u8 command[] = {
 		ALAUDA_BULK_CMD, ALAUDA_BULK_WRITE_PAGE, PBA_HI(pba),
 		PBA_ZONE(pba), 0, PBA_LO(pba) + page, 32, 0, al->port
 	};
 	int i, err;

 	for (i=0; i<3; i++)
 		sg.urb[i] = NULL;

 	err = -ENOMEM;
 	for (i=0; i<3; i++) {
 		sg.urb[i] = usb_alloc_urb(0, GFP_NOIO);
 		if (!sg.urb[i])
 			goto out;
 	}
 	init_completion(&sg.comp);
 	usb_fill_bulk_urb(sg.urb[0], al->dev, al->bulk_out, command, 9,
 			alauda_complete, NULL);
 	usb_fill_bulk_urb(sg.urb[1], al->dev, al->write_out, buf,mtd->writesize,
 			alauda_complete, NULL);
 	usb_fill_bulk_urb(sg.urb[2], al->dev, al->write_out, oob, 16,
 			alauda_complete, &sg.comp);

 	mutex_lock(&al->card_mutex);
 	for (i=0; i<3; i++) {
 		err = usb_submit_urb(sg.urb[i], GFP_NOIO);
 		if (err)
 			goto cancel;
 	}
 	if (!wait_for_completion_timeout(&sg.comp, TIMEOUT)) {
 		err = -ETIMEDOUT;
 cancel:
 		for (i=0; i<3; i++) {
 			usb_kill_urb(sg.urb[i]);
 		}
 	}
 	mutex_unlock(&al->card_mutex);

 out:
 	usb_free_urb(sg.urb[0]);
 	usb_free_urb(sg.urb[1]);
 	usb_free_urb(sg.urb[2]);
 	return err;
 }

 static int alauda_erase_block(struct mtd_info *mtd, loff_t ofs)
 {
 	struct alauda_sg_request sg;
 	struct alauda *al = mtd->priv;
 	u32 pba = ofs >> al->card->blockshift;
 	u8 command[] = {
 		ALAUDA_BULK_CMD, ALAUDA_BULK_ERASE_BLOCK, PBA_HI(pba),
 		PBA_ZONE(pba), 0, PBA_LO(pba), 0x02, 0, al->port
 	};
 	u8 buf[2];
 	int i, err;

 	for (i=0; i<2; i++)
 		sg.urb[i] = NULL;

 	err = -ENOMEM;
 	for (i=0; i<2; i++) {
 		sg.urb[i] = usb_alloc_urb(0, GFP_NOIO);
 		if (!sg.urb[i])
 			goto out;
 	}
 	init_completion(&sg.comp);
 	usb_fill_bulk_urb(sg.urb[0], al->dev, al->bulk_out, command, 9,
 			alauda_complete, NULL);
 	usb_fill_bulk_urb(sg.urb[1], al->dev, al->bulk_in, buf, 2,
 			alauda_complete, &sg.comp);

 	mutex_lock(&al->card_mutex);
 	for (i=0; i<2; i++) {
 		err = usb_submit_urb(sg.urb[i], GFP_NOIO);
 		if (err)
 			goto cancel;
 	}
 	if (!wait_for_completion_timeout(&sg.comp, TIMEOUT)) {
 		err = -ETIMEDOUT;
 cancel:
 		for (i=0; i<2; i++) {
 			usb_kill_urb(sg.urb[i]);
 		}
 	}
 	mutex_unlock(&al->card_mutex);

 out:
 	usb_free_urb(sg.urb[0]);
 	usb_free_urb(sg.urb[1]);
 	return err;
 }

 static int alauda_read_oob(struct mtd_info *mtd, loff_t from, void *oob)
 {
 	static u8 ignore_buf[512]; /* write only */

 	return __alauda_read_page(mtd, from, ignore_buf, oob);
 }

 static int popcount8(u8 c)
 {
 	int ret = 0;

 	for ( ; c; c>>=1)
 		ret += c & 1;
 	return ret;
 }

 static int alauda_isbad(struct mtd_info *mtd, loff_t ofs)
 {
 	u8 oob[16];
 	int err;

 	err = alauda_read_oob(mtd, ofs, oob);
 	if (err)
 		return err;

 	/* A block is marked bad if two or more bits are zero */
 	return popcount8(oob[5]) >= 7 ? 0 : 1;
 }

 static int alauda_bounce_read(struct mtd_info *mtd, loff_t from, size_t len,
 		size_t *retlen, u_char *buf)
 {
 	struct alauda *al = mtd->priv;
 	void *bounce_buf;
 	int err, corrected=0, uncorrected=0;

 	bounce_buf = kmalloc(mtd->writesize, GFP_KERNEL);
 	if (!bounce_buf)
 		return -ENOMEM;

 	*retlen = len;
 	while (len) {
 		u8 oob[16];
 		size_t byte = from & al->bytemask;
 		size_t cplen = min(len, mtd->writesize - byte);

 		err = alauda_read_page(mtd, from, bounce_buf, oob,
 				&corrected, &uncorrected);
 		if (err)
 			goto out;

 		memcpy(buf, bounce_buf + byte, cplen);
 		buf += cplen;
 		from += cplen;
 		len -= cplen;
 	}
 	err = 0;
 	if (corrected)
 		err = -EUCLEAN;
 	if (uncorrected)
 		err = -EBADMSG;
 out:
 	kfree(bounce_buf);
 	return err;
 }

 static int alauda_read(struct mtd_info *mtd, loff_t from, size_t len,
 		size_t *retlen, u_char *buf)
 {
 	struct alauda *al = mtd->priv;
 	int err, corrected=0, uncorrected=0;

 	if ((from & al->bytemask) || (len & al->bytemask))
 		return alauda_bounce_read(mtd, from, len, retlen, buf);

 	*retlen = len;
 	while (len) {
 		u8 oob[16];

 		err = alauda_read_page(mtd, from, buf, oob,
 				&corrected, &uncorrected);
 		if (err)
 			return err;

 		buf += mtd->writesize;
 		from += mtd->writesize;
 		len -= mtd->writesize;
 	}
 	err = 0;
 	if (corrected)
 		err = -EUCLEAN;
 	if (uncorrected)
 		err = -EBADMSG;
 	return err;
 }

 static int alauda_write(struct mtd_info *mtd, loff_t to, size_t len,
 		size_t *retlen, const u_char *buf)
 {
 	struct alauda *al = mtd->priv;
 	int err;

 	if ((to & al->bytemask) || (len & al->bytemask))
 		return -EINVAL;

 	*retlen = len;
 	while (len) {
 		u32 page = (to >> al->card->pageshift) & al->pagemask;
 		u8 oob[16] = {	'h', 'e', 'l', 'l', 'o', 0xff, 0xff, 0xff,
 				0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff};

 		/* don't write to bad blocks */
 		if (page == 0) {
 			err = alauda_isbad(mtd, to);
 			if (err) {
 				return -EIO;
 			}
 		}
 		nand_calculate_ecc(mtd, buf, &oob[13]);
 		nand_calculate_ecc(mtd, buf+256, &oob[8]);

 		err = alauda_write_page(mtd, to, (void*)buf, oob);
 		if (err)
 			return err;

 		buf += mtd->writesize;
 		to += mtd->writesize;
 		len -= mtd->writesize;
 	}
 	return 0;
 }

 static int __alauda_erase(struct mtd_info *mtd, struct erase_info *instr)
 {
 	struct alauda *al = mtd->priv;
 	u32 ofs = instr->addr;
 	u32 len = instr->len;
 	int err;

 	if ((ofs & al->blockmask) || (len & al->blockmask))
 		return -EINVAL;

 	while (len) {
 		/* don't erase bad blocks */
 		err = alauda_isbad(mtd, ofs);
 		if (err > 0)
 			err = -EIO;
 		if (err < 0)
 			return err;

 		err = alauda_erase_block(mtd, ofs);
 		if (err < 0)
 			return err;

 		ofs += mtd->erasesize;
 		len -= mtd->erasesize;
 	}
 	return 0;
 }

 static int alauda_erase(struct mtd_info *mtd, struct erase_info *instr)
 {
 	int err;

 	err = __alauda_erase(mtd, instr);
 	instr->state = err ? MTD_ERASE_FAILED : MTD_ERASE_DONE;
 	mtd_erase_callback(instr);
 	return err;
 }

 static int alauda_init_media(struct alauda *al)
 {
 	u8 buf[4], *b0=buf, *b1=buf+1;
 	struct alauda_card *card;
 	struct mtd_info *mtd;
 	int err;

 	mtd = kzalloc(sizeof(*mtd), GFP_KERNEL);
 	if (!mtd)
 		return -ENOMEM;

 	for (;;) {
 		err = alauda_get_media_status(al, buf);
 		if (err < 0)
 			goto error;
 		if (*b0 & 0x10)
 			break;
 		msleep(20);
 	}

 	err = alauda_ack_media(al);
 	if (err)
 		goto error;

 	msleep(10);

 	err = alauda_get_media_status(al, buf);
 	if (err < 0)
 		goto error;

 	if (*b0 != 0x14) {
 		/* media not ready */
 		err = -EIO;
 		goto error;
 	}
 	err = alauda_get_media_signatures(al, buf);
 	if (err < 0)
 		goto error;

 	card = get_card(*b1);
 	if (!card) {
 		printk(KERN_ERR"Alauda: unknown card id %02x\n", *b1);
 		err = -EIO;
 		goto error;
 	}
 	printk(KERN_INFO"pagesize=%x\nerasesize=%x\nsize=%xMiB\n",
 			1<<card->pageshift, 1<<card->blockshift,
 			1<<(card->chipshift-20));
 	al->card = card;
 	al->pagemask = (1 << (card->blockshift - card->pageshift)) - 1;
 	al->bytemask = (1 << card->pageshift) - 1;
 	al->blockmask = (1 << card->blockshift) - 1;

 	mtd->name = "alauda";
 	mtd->size = 1<<card->chipshift;
 	mtd->erasesize = 1<<card->blockshift;
 	mtd->writesize = 1<<card->pageshift;
 	mtd->type = MTD_NANDFLASH;
 	mtd->flags = MTD_CAP_NANDFLASH;
 	mtd->read = alauda_read;
 	mtd->write = alauda_write;
 	mtd->erase = alauda_erase;
 	mtd->block_isbad = alauda_isbad;
 	mtd->priv = al;
 	mtd->owner = THIS_MODULE;

 	err = add_mtd_device(mtd);
 	if (err) {
 		err = -ENFILE;
 		goto error;
 	}

 	al->mtd = mtd;
 	alauda_reset(al); /* no clue whether this is necessary */
 	return 0;
 error:
 	kfree(mtd);
 	return err;
 }

 static int alauda_check_media(struct alauda *al)
 {
 	u8 buf[2], *b0 = buf, *b1 = buf+1;
 	int err;

 	err = alauda_get_media_status(al, buf);
 	if (err < 0)
 		return err;

 	if ((*b1 & 0x01) == 0) {
 		/* door open */
 		return -EIO;
 	}
 	if ((*b0 & 0x80) || ((*b0 & 0x1F) == 0x10)) {
 		/* no media ? */
 		return -EIO;
 	}
 	if (*b0 & 0x08) {
 		/* media change ? */
 		return alauda_init_media(al);
 	}
 	return 0;
 }

 static int alauda_probe(struct usb_interface *interface,
 		const struct usb_device_id *id)
 {
 	struct alauda *al;
 	struct usb_host_interface *iface;
 	struct usb_endpoint_descriptor *ep,
 			*ep_in=NULL, *ep_out=NULL, *ep_wr=NULL;
 	int i, err = -ENOMEM;

 	al = kzalloc(2*sizeof(*al), GFP_KERNEL);
 	if (!al)
 		goto error;

 	kref_init(&al->kref);
 	usb_set_intfdata(interface, al);

 	al->dev = usb_get_dev(interface_to_usbdev(interface));
 	al->interface = interface;

 	iface = interface->cur_altsetting;
 	for (i = 0; i < iface->desc.bNumEndpoints; ++i) {
 		ep = &iface->endpoint[i].desc;

 		if (usb_endpoint_is_bulk_in(ep)) {
 			ep_in = ep;
 		} else if (usb_endpoint_is_bulk_out(ep)) {
 			if (i==0)
 				ep_wr = ep;
 			else
 				ep_out = ep;
 		}
 	}
 	err = -EIO;
 	if (!ep_wr || !ep_in || !ep_out)
 		goto error;

 	al->write_out = usb_sndbulkpipe(al->dev,
 			usb_endpoint_num(ep_wr));
 	al->bulk_in = usb_rcvbulkpipe(al->dev,
 			usb_endpoint_num(ep_in));
 	al->bulk_out = usb_sndbulkpipe(al->dev,
 			usb_endpoint_num(ep_out));

 	/* second device is identical up to now */
 	memcpy(al+1, al, sizeof(*al));

 	mutex_init(&al[0].card_mutex);
 	mutex_init(&al[1].card_mutex);

 	al[0].port = ALAUDA_PORT_XD;
 	al[1].port = ALAUDA_PORT_SM;

 	dev_info(&interface->dev, "alauda probed\n");
 	alauda_check_media(al);
 	alauda_check_media(al+1);

 	return 0;

 error:
 	if (al)
 		kref_put(&al->kref, alauda_delete);
 	return err;
 }

 static void alauda_disconnect(struct usb_interface *interface)
 {
 	struct alauda *al;

 	al = usb_get_intfdata(interface);
 	usb_set_intfdata(interface, NULL);

 	/* FIXME: prevent more I/O from starting */

 	/* decrement our usage count */
 	if (al)
 		kref_put(&al->kref, alauda_delete);

 	dev_info(&interface->dev, "alauda gone");
 }

 static struct usb_driver alauda_driver = {
 	.name =		"alauda",
 	.probe =	alauda_probe,
 	.disconnect =	alauda_disconnect,
 	.id_table =	alauda_table,
 };

 static int __init alauda_init(void)
 {
 	return usb_register(&alauda_driver);
 }

 static void __exit alauda_exit(void)
 {
 	usb_deregister(&alauda_driver);
 }

 module_init(alauda_init);
 module_exit(alauda_exit);

 MODULE_LICENSE("GPL");
	/*
	* MTD driver for Alauda chips
	*
	* Copyright (C) 2007 Joern Engel <joern@logfs.org>
	*
	* Based on drivers/usb/usb-skeleton.c which is:
	* Copyright (C) 2001-2004 Greg Kroah-Hartman (greg@kroah.com)
	* and on drivers/usb/storage/alauda.c, which is:
	* (c) 2005 Daniel Drake <dsd@gentoo.org>
	*
	* Idea and initial work by Arnd Bergmann <arnd@arndb.de>
	*/
	#include <linux/kernel.h>
	#include <linux/errno.h>
	#include <linux/init.h>
	#include <linux/slab.h>
	#include <linux/module.h>
	#include <linux/kref.h>
	#include <linux/usb.h>
	#include <linux/mutex.h>
	#include <linux/mtd/mtd.h>
	#include <linux/mtd/nand_ecc.h>

	/* Control commands */
	#define ALAUDA_GET_XD_MEDIA_STATUS 0x08
	#define ALAUDA_ACK_XD_MEDIA_CHANGE 0x0a
	#define ALAUDA_GET_XD_MEDIA_SIG 0x86

	/* Common prefix */
	#define ALAUDA_BULK_CMD 0x40

	/* The two ports */
	#define ALAUDA_PORT_XD 0x00
	#define ALAUDA_PORT_SM 0x01

	/* Bulk commands */
	#define ALAUDA_BULK_READ_PAGE 0x84
	#define ALAUDA_BULK_READ_OOB 0x85 /* don't use, there's a chip bug */
	#define ALAUDA_BULK_READ_BLOCK 0x94
	#define ALAUDA_BULK_ERASE_BLOCK 0xa3
	#define ALAUDA_BULK_WRITE_PAGE 0xa4
	#define ALAUDA_BULK_WRITE_BLOCK 0xb4
	#define ALAUDA_BULK_RESET_MEDIA 0xe0

	/* Address shifting */
	#define PBA_LO(pba) ((pba & 0xF) << 5)
	#define PBA_HI(pba) (pba >> 3)
	#define PBA_ZONE(pba) (pba >> 11)

	#define TIMEOUT HZ

	static struct usb_device_id alauda_table [] = {
	{ USB_DEVICE(0x0584, 0x0008) }, /* Fujifilm DPC-R1 */
	{ USB_DEVICE(0x07b4, 0x010a) }, /* Olympus MAUSB-10 */
	{ }
	};
	MODULE_DEVICE_TABLE(usb, alauda_table);

	struct alauda_card {
	u8 id; /* id byte */
	u8 chipshift; /* 1<<chipshift total size */
	u8 pageshift; /* 1<<pageshift page size */
	u8 blockshift; /* 1<<blockshift block size */
	};

	struct alauda {
	struct usb_device *dev;
	struct usb_interface *interface;
	struct mtd_info *mtd;
	struct alauda_card *card;
	struct mutex card_mutex;
	u32 pagemask;
	u32 bytemask;
	u32 blockmask;
	unsigned int write_out;
	unsigned int bulk_in;
	unsigned int bulk_out;
	u8 port;
	struct kref kref;
	};

	static struct alauda_card alauda_card_ids[] = {
	/* NAND flash */
	{ 0x6e, 20, 8, 12}, /* 1 MB */
	{ 0xe8, 20, 8, 12}, /* 1 MB */
	{ 0xec, 20, 8, 12}, /* 1 MB */
	{ 0x64, 21, 8, 12}, /* 2 MB */
	{ 0xea, 21, 8, 12}, /* 2 MB */
	{ 0x6b, 22, 9, 13}, /* 4 MB */
	{ 0xe3, 22, 9, 13}, /* 4 MB */
	{ 0xe5, 22, 9, 13}, /* 4 MB */
	{ 0xe6, 23, 9, 13}, /* 8 MB */
	{ 0x73, 24, 9, 14}, /* 16 MB */
	{ 0x75, 25, 9, 14}, /* 32 MB */
	{ 0x76, 26, 9, 14}, /* 64 MB */
	{ 0x79, 27, 9, 14}, /* 128 MB */
	{ 0x71, 28, 9, 14}, /* 256 MB */

	/* MASK ROM */
	{ 0x5d, 21, 9, 13}, /* 2 MB */
	{ 0xd5, 22, 9, 13}, /* 4 MB */
	{ 0xd6, 23, 9, 13}, /* 8 MB */
	{ 0x57, 24, 9, 13}, /* 16 MB */
	{ 0x58, 25, 9, 13}, /* 32 MB */
	{ }
	};

	static struct alauda_card *get_card(u8 id)
	{
	struct alauda_card *card;

	for (card = alauda_card_ids; card->id; card++)
	if (card->id == id)
	return card;
	return NULL;
	}

	static void alauda_delete(struct kref *kref)
	{
	struct alauda *al = container_of(kref, struct alauda, kref);

	if (al->mtd) {
	del_mtd_device(al->mtd);
	kfree(al->mtd);
	}
	usb_put_dev(al->dev);
	kfree(al);
	}

	static int alauda_get_media_status(struct alauda al, void buf)
	{
	int ret;

	mutex_lock(&al->card_mutex);
	ret = usb_control_msg(al->dev, usb_rcvctrlpipe(al->dev, 0),
	ALAUDA_GET_XD_MEDIA_STATUS, 0xc0, 0, 1, buf, 2, HZ);
	mutex_unlock(&al->card_mutex);
	return ret;
	}

	static int alauda_ack_media(struct alauda *al)
	{
	int ret;

	mutex_lock(&al->card_mutex);
	ret = usb_control_msg(al->dev, usb_sndctrlpipe(al->dev, 0),
	ALAUDA_ACK_XD_MEDIA_CHANGE, 0x40, 0, 1, NULL, 0, HZ);
	mutex_unlock(&al->card_mutex);
	return ret;
	}

	static int alauda_get_media_signatures(struct alauda al, void buf)
	{
	int ret;

	mutex_lock(&al->card_mutex);
	ret = usb_control_msg(al->dev, usb_rcvctrlpipe(al->dev, 0),
	ALAUDA_GET_XD_MEDIA_SIG, 0xc0, 0, 0, buf, 4, HZ);
	mutex_unlock(&al->card_mutex);
	return ret;
	}

	static void alauda_reset(struct alauda *al)
	{
	u8 command[] = {
	ALAUDA_BULK_CMD, ALAUDA_BULK_RESET_MEDIA, 0, 0,
	0, 0, 0, 0, al->port
	};
	mutex_lock(&al->card_mutex);
	usb_bulk_msg(al->dev, al->bulk_out, command, 9, NULL, HZ);
	mutex_unlock(&al->card_mutex);
	}

	static void correct_data(void buf, void read_ecc,
	int corrected, int uncorrected)
	{
	u8 calc_ecc[3];
	int err;

	nand_calculate_ecc(NULL, buf, calc_ecc);
	err = nand_correct_data(NULL, buf, read_ecc, calc_ecc);
	if (err) {
	if (err > 0)
	(*corrected)++;
	else
	(*uncorrected)++;
	}
	}

	struct alauda_sg_request {
	struct urb *urb[3];
	struct completion comp;
	};

	static void alauda_complete(struct urb *urb)
	{
	struct completion *comp = urb->context;

	if (comp)
	complete(comp);
	}

	static int __alauda_read_page(struct mtd_info mtd, loff_t from, void buf,
	void *oob)
	{
	struct alauda_sg_request sg;
	struct alauda *al = mtd->priv;
	u32 pba = from >> al->card->blockshift;
	u32 page = (from >> al->card->pageshift) & al->pagemask;
	u8 command[] = {
	ALAUDA_BULK_CMD, ALAUDA_BULK_READ_PAGE, PBA_HI(pba),
	PBA_ZONE(pba), 0, PBA_LO(pba) + page, 1, 0, al->port
	};
	int i, err;

	for (i=0; i<3; i++)
	sg.urb[i] = NULL;

	err = -ENOMEM;
	for (i=0; i<3; i++) {
	sg.urb[i] = usb_alloc_urb(0, GFP_NOIO);
	if (!sg.urb[i])
	goto out;
	}
	init_completion(&sg.comp);
	usb_fill_bulk_urb(sg.urb[0], al->dev, al->bulk_out, command, 9,
	alauda_complete, NULL);
	usb_fill_bulk_urb(sg.urb[1], al->dev, al->bulk_in, buf, mtd->writesize,
	alauda_complete, NULL);
	usb_fill_bulk_urb(sg.urb[2], al->dev, al->bulk_in, oob, 16,
	alauda_complete, &sg.comp);

	mutex_lock(&al->card_mutex);
	for (i=0; i<3; i++) {
	err = usb_submit_urb(sg.urb[i], GFP_NOIO);
	if (err)
	goto cancel;
	}
	if (!wait_for_completion_timeout(&sg.comp, TIMEOUT)) {
	err = -ETIMEDOUT;
	cancel:
	for (i=0; i<3; i++) {
	usb_kill_urb(sg.urb[i]);
	}
	}
	mutex_unlock(&al->card_mutex);

	out:
	usb_free_urb(sg.urb[0]);
	usb_free_urb(sg.urb[1]);
	usb_free_urb(sg.urb[2]);
	return err;
	}

	static int alauda_read_page(struct mtd_info *mtd, loff_t from,
	void buf, u8 oob, int corrected, int uncorrected)
	{
	int err;

	err = __alauda_read_page(mtd, from, buf, oob);
	if (err)
	return err;
	correct_data(buf, oob+13, corrected, uncorrected);
	correct_data(buf+256, oob+8, corrected, uncorrected);
	return 0;
	}

	static int alauda_write_page(struct mtd_info mtd, loff_t to, void buf,
	void *oob)
	{
	struct alauda_sg_request sg;
	struct alauda *al = mtd->priv;
	u32 pba = to >> al->card->blockshift;
	u32 page = (to >> al->card->pageshift) & al->pagemask;
	u8 command[] = {
	ALAUDA_BULK_CMD, ALAUDA_BULK_WRITE_PAGE, PBA_HI(pba),
	PBA_ZONE(pba), 0, PBA_LO(pba) + page, 32, 0, al->port
	};
	int i, err;

	for (i=0; i<3; i++)
	sg.urb[i] = NULL;

	err = -ENOMEM;
	for (i=0; i<3; i++) {
	sg.urb[i] = usb_alloc_urb(0, GFP_NOIO);
	if (!sg.urb[i])
	goto out;
	}
	init_completion(&sg.comp);
	usb_fill_bulk_urb(sg.urb[0], al->dev, al->bulk_out, command, 9,
	alauda_complete, NULL);
	usb_fill_bulk_urb(sg.urb[1], al->dev, al->write_out, buf,mtd->writesize,
	alauda_complete, NULL);
	usb_fill_bulk_urb(sg.urb[2], al->dev, al->write_out, oob, 16,
	alauda_complete, &sg.comp);

	mutex_lock(&al->card_mutex);
	for (i=0; i<3; i++) {
	err = usb_submit_urb(sg.urb[i], GFP_NOIO);
	if (err)
	goto cancel;
	}
	if (!wait_for_completion_timeout(&sg.comp, TIMEOUT)) {
	err = -ETIMEDOUT;
	cancel:
	for (i=0; i<3; i++) {
	usb_kill_urb(sg.urb[i]);
	}
	}
	mutex_unlock(&al->card_mutex);

	out:
	usb_free_urb(sg.urb[0]);
	usb_free_urb(sg.urb[1]);
	usb_free_urb(sg.urb[2]);
	return err;
	}

	static int alauda_erase_block(struct mtd_info *mtd, loff_t ofs)
	{
	struct alauda_sg_request sg;
	struct alauda *al = mtd->priv;
	u32 pba = ofs >> al->card->blockshift;
	u8 command[] = {
	ALAUDA_BULK_CMD, ALAUDA_BULK_ERASE_BLOCK, PBA_HI(pba),
	PBA_ZONE(pba), 0, PBA_LO(pba), 0x02, 0, al->port
	};
	u8 buf[2];
	int i, err;

	for (i=0; i<2; i++)
	sg.urb[i] = NULL;

	err = -ENOMEM;
	for (i=0; i<2; i++) {
	sg.urb[i] = usb_alloc_urb(0, GFP_NOIO);
	if (!sg.urb[i])
	goto out;
	}
	init_completion(&sg.comp);
	usb_fill_bulk_urb(sg.urb[0], al->dev, al->bulk_out, command, 9,
	alauda_complete, NULL);
	usb_fill_bulk_urb(sg.urb[1], al->dev, al->bulk_in, buf, 2,
	alauda_complete, &sg.comp);

	mutex_lock(&al->card_mutex);
	for (i=0; i<2; i++) {
	err = usb_submit_urb(sg.urb[i], GFP_NOIO);
	if (err)
	goto cancel;
	}
	if (!wait_for_completion_timeout(&sg.comp, TIMEOUT)) {
	err = -ETIMEDOUT;
	cancel:
	for (i=0; i<2; i++) {
	usb_kill_urb(sg.urb[i]);
	}
	}
	mutex_unlock(&al->card_mutex);

	out:
	usb_free_urb(sg.urb[0]);
	usb_free_urb(sg.urb[1]);
	return err;
	}

	static int alauda_read_oob(struct mtd_info mtd, loff_t from, void oob)
	{
	static u8 ignore_buf[512]; /* write only */

	return __alauda_read_page(mtd, from, ignore_buf, oob);
	}

	static int popcount8(u8 c)
	{
	int ret = 0;

	for ( ; c; c>>=1)
	ret += c & 1;
	return ret;
	}

	static int alauda_isbad(struct mtd_info *mtd, loff_t ofs)
	{
	u8 oob[16];
	int err;

	err = alauda_read_oob(mtd, ofs, oob);
	if (err)
	return err;

	/* A block is marked bad if two or more bits are zero */
	return popcount8(oob[5]) >= 7 ? 0 : 1;
	}

	static int alauda_bounce_read(struct mtd_info *mtd, loff_t from, size_t len,
	size_t retlen, u_char buf)
	{
	struct alauda *al = mtd->priv;
	void *bounce_buf;
	int err, corrected=0, uncorrected=0;

	bounce_buf = kmalloc(mtd->writesize, GFP_KERNEL);
	if (!bounce_buf)
	return -ENOMEM;

	*retlen = len;
	while (len) {
	u8 oob[16];
	size_t byte = from & al->bytemask;
	size_t cplen = min(len, mtd->writesize - byte);

	err = alauda_read_page(mtd, from, bounce_buf, oob,
	&corrected, &uncorrected);
	if (err)
	goto out;

	memcpy(buf, bounce_buf + byte, cplen);
	buf += cplen;
	from += cplen;
	len -= cplen;
	}
	err = 0;
	if (corrected)
	err = -EUCLEAN;
	if (uncorrected)
	err = -EBADMSG;
	out:
	kfree(bounce_buf);
	return err;
	}

	static int alauda_read(struct mtd_info *mtd, loff_t from, size_t len,
	size_t retlen, u_char buf)
	{
	struct alauda *al = mtd->priv;
	int err, corrected=0, uncorrected=0;

	if ((from & al->bytemask) \|\| (len & al->bytemask))
	return alauda_bounce_read(mtd, from, len, retlen, buf);

	*retlen = len;
	while (len) {
	u8 oob[16];

	err = alauda_read_page(mtd, from, buf, oob,
	&corrected, &uncorrected);
	if (err)
	return err;

	buf += mtd->writesize;
	from += mtd->writesize;
	len -= mtd->writesize;
	}
	err = 0;
	if (corrected)
	err = -EUCLEAN;
	if (uncorrected)
	err = -EBADMSG;
	return err;
	}

	static int alauda_write(struct mtd_info *mtd, loff_t to, size_t len,
	size_t retlen, const u_char buf)
	{
	struct alauda *al = mtd->priv;
	int err;

	if ((to & al->bytemask) \|\| (len & al->bytemask))
	return -EINVAL;

	*retlen = len;
	while (len) {
	u32 page = (to >> al->card->pageshift) & al->pagemask;
	u8 oob[16] = { 'h', 'e', 'l', 'l', 'o', 0xff, 0xff, 0xff,
	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff};

	/* don't write to bad blocks */
	if (page == 0) {
	err = alauda_isbad(mtd, to);
	if (err) {
	return -EIO;
	}
	}
	nand_calculate_ecc(mtd, buf, &oob[13]);
	nand_calculate_ecc(mtd, buf+256, &oob[8]);

	err = alauda_write_page(mtd, to, (void*)buf, oob);
	if (err)
	return err;

	buf += mtd->writesize;
	to += mtd->writesize;
	len -= mtd->writesize;
	}
	return 0;
	}

	static int __alauda_erase(struct mtd_info mtd, struct erase_info instr)
	{
	struct alauda *al = mtd->priv;
	u32 ofs = instr->addr;
	u32 len = instr->len;
	int err;

	if ((ofs & al->blockmask) \|\| (len & al->blockmask))
	return -EINVAL;

	while (len) {
	/* don't erase bad blocks */
	err = alauda_isbad(mtd, ofs);
	if (err > 0)
	err = -EIO;
	if (err < 0)
	return err;

	err = alauda_erase_block(mtd, ofs);
	if (err < 0)
	return err;

	ofs += mtd->erasesize;
	len -= mtd->erasesize;
	}
	return 0;
	}

	static int alauda_erase(struct mtd_info mtd, struct erase_info instr)
	{
	int err;

	err = __alauda_erase(mtd, instr);
	instr->state = err ? MTD_ERASE_FAILED : MTD_ERASE_DONE;
	mtd_erase_callback(instr);
	return err;
	}

	static int alauda_init_media(struct alauda *al)
	{
	u8 buf[4], b0=buf, b1=buf+1;
	struct alauda_card *card;
	struct mtd_info *mtd;
	int err;

	mtd = kzalloc(sizeof(*mtd), GFP_KERNEL);
	if (!mtd)
	return -ENOMEM;

	for (;;) {
	err = alauda_get_media_status(al, buf);
	if (err < 0)
	goto error;
	if (*b0 & 0x10)
	break;
	msleep(20);
	}

	err = alauda_ack_media(al);
	if (err)
	goto error;

	msleep(10);

	err = alauda_get_media_status(al, buf);
	if (err < 0)
	goto error;

	if (*b0 != 0x14) {
	/* media not ready */
	err = -EIO;
	goto error;
	}
	err = alauda_get_media_signatures(al, buf);
	if (err < 0)
	goto error;

	card = get_card(*b1);
	if (!card) {
	printk(KERN_ERR"Alauda: unknown card id %02x\n", *b1);
	err = -EIO;
	goto error;
	}
	printk(KERN_INFO"pagesize=%x\nerasesize=%x\nsize=%xMiB\n",
	1<<card->pageshift, 1<<card->blockshift,
	1<<(card->chipshift-20));
	al->card = card;
	al->pagemask = (1 << (card->blockshift - card->pageshift)) - 1;
	al->bytemask = (1 << card->pageshift) - 1;
	al->blockmask = (1 << card->blockshift) - 1;

	mtd->name = "alauda";
	mtd->size = 1<<card->chipshift;
	mtd->erasesize = 1<<card->blockshift;
	mtd->writesize = 1<<card->pageshift;
	mtd->type = MTD_NANDFLASH;
	mtd->flags = MTD_CAP_NANDFLASH;
	mtd->read = alauda_read;
	mtd->write = alauda_write;
	mtd->erase = alauda_erase;
	mtd->block_isbad = alauda_isbad;
	mtd->priv = al;
	mtd->owner = THIS_MODULE;

	err = add_mtd_device(mtd);
	if (err) {
	err = -ENFILE;
	goto error;
	}

	al->mtd = mtd;
	alauda_reset(al); /* no clue whether this is necessary */
	return 0;
	error:
	kfree(mtd);
	return err;
	}

	static int alauda_check_media(struct alauda *al)
	{
	u8 buf[2], b0 = buf, b1 = buf+1;
	int err;

	err = alauda_get_media_status(al, buf);
	if (err < 0)
	return err;

	if ((*b1 & 0x01) == 0) {
	/* door open */
	return -EIO;
	}
	if ((b0 & 0x80) \|\| ((b0 & 0x1F) == 0x10)) {
	/* no media ? */
	return -EIO;
	}
	if (*b0 & 0x08) {
	/* media change ? */
	return alauda_init_media(al);
	}
	return 0;
	}

	static int alauda_probe(struct usb_interface *interface,
	const struct usb_device_id *id)
	{
	struct alauda *al;
	struct usb_host_interface *iface;
	struct usb_endpoint_descriptor *ep,
	ep_in=NULL, ep_out=NULL, *ep_wr=NULL;
	int i, err = -ENOMEM;

	al = kzalloc(2sizeof(al), GFP_KERNEL);
	if (!al)
	goto error;

	kref_init(&al->kref);
	usb_set_intfdata(interface, al);

	al->dev = usb_get_dev(interface_to_usbdev(interface));
	al->interface = interface;

	iface = interface->cur_altsetting;
	for (i = 0; i < iface->desc.bNumEndpoints; ++i) {
	ep = &iface->endpoint[i].desc;

	if (usb_endpoint_is_bulk_in(ep)) {
	ep_in = ep;
	} else if (usb_endpoint_is_bulk_out(ep)) {
	if (i==0)
	ep_wr = ep;
	else
	ep_out = ep;
	}
	}
	err = -EIO;
	if (!ep_wr \|\| !ep_in \|\| !ep_out)
	goto error;

	al->write_out = usb_sndbulkpipe(al->dev,
	usb_endpoint_num(ep_wr));
	al->bulk_in = usb_rcvbulkpipe(al->dev,
	usb_endpoint_num(ep_in));
	al->bulk_out = usb_sndbulkpipe(al->dev,
	usb_endpoint_num(ep_out));

	/* second device is identical up to now */
	memcpy(al+1, al, sizeof(*al));

	mutex_init(&al[0].card_mutex);
	mutex_init(&al[1].card_mutex);

	al[0].port = ALAUDA_PORT_XD;
	al[1].port = ALAUDA_PORT_SM;

	dev_info(&interface->dev, "alauda probed\n");
	alauda_check_media(al);
	alauda_check_media(al+1);

	return 0;

	error:
	if (al)
	kref_put(&al->kref, alauda_delete);
	return err;
	}

	static void alauda_disconnect(struct usb_interface *interface)
	{
	struct alauda *al;

	al = usb_get_intfdata(interface);
	usb_set_intfdata(interface, NULL);

	/* FIXME: prevent more I/O from starting */

	/* decrement our usage count */
	if (al)
	kref_put(&al->kref, alauda_delete);

	dev_info(&interface->dev, "alauda gone");
	}

	static struct usb_driver alauda_driver = {
	.name = "alauda",
	.probe = alauda_probe,
	.disconnect = alauda_disconnect,
	.id_table = alauda_table,
	};

	static int __init alauda_init(void)
	{
	return usb_register(&alauda_driver);
	}

	static void __exit alauda_exit(void)
	{
	usb_deregister(&alauda_driver);
	}

	module_init(alauda_init);
	module_exit(alauda_exit);

	MODULE_LICENSE("GPL");