Initial import

1 files changed, 1112 insertions, 0 deletions

diff --git a/drivers/block/mg_disk.c b/drivers/block/mg_disk.c
new file mode 100644
index 000000000..145ce2aa2
--- /dev/null
+++ b/drivers/block/mg_disk.c
@@ -0,0 +1,1112 @@
+/*
+ *  drivers/block/mg_disk.c
+ *
+ *  Support for the mGine m[g]flash IO mode.
+ *  Based on legacy hd.c
+ *
+ * (c) 2008 mGine Co.,LTD
+ * (c) 2008 unsik Kim <donari75@gmail.com>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2 as
+ *  published by the Free Software Foundation.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/blkdev.h>
+#include <linux/hdreg.h>
+#include <linux/ata.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/platform_device.h>
+#include <linux/gpio.h>
+#include <linux/mg_disk.h>
+#include <linux/slab.h>
+
+#define MG_RES_SEC (CONFIG_MG_DISK_RES << 1)
+
+/* name for block device */
+#define MG_DISK_NAME "mgd"
+
+#define MG_DISK_MAJ 0
+#define MG_DISK_MAX_PART 16
+#define MG_SECTOR_SIZE 512
+#define MG_MAX_SECTS 256
+
+/* Register offsets */
+#define MG_BUFF_OFFSET			0x8000
+#define MG_REG_OFFSET			0xC000
+#define MG_REG_FEATURE			(MG_REG_OFFSET + 2)	/* write case */
+#define MG_REG_ERROR			(MG_REG_OFFSET + 2)	/* read case */
+#define MG_REG_SECT_CNT			(MG_REG_OFFSET + 4)
+#define MG_REG_SECT_NUM			(MG_REG_OFFSET + 6)
+#define MG_REG_CYL_LOW			(MG_REG_OFFSET + 8)
+#define MG_REG_CYL_HIGH			(MG_REG_OFFSET + 0xA)
+#define MG_REG_DRV_HEAD			(MG_REG_OFFSET + 0xC)
+#define MG_REG_COMMAND			(MG_REG_OFFSET + 0xE)	/* write case */
+#define MG_REG_STATUS			(MG_REG_OFFSET + 0xE)	/* read  case */
+#define MG_REG_DRV_CTRL			(MG_REG_OFFSET + 0x10)
+#define MG_REG_BURST_CTRL		(MG_REG_OFFSET + 0x12)
+
+/* handy status */
+#define MG_STAT_READY	(ATA_DRDY | ATA_DSC)
+#define MG_READY_OK(s)	(((s) & (MG_STAT_READY | (ATA_BUSY | ATA_DF | \
+				 ATA_ERR))) == MG_STAT_READY)
+
+/* error code for others */
+#define MG_ERR_NONE		0
+#define MG_ERR_TIMEOUT		0x100
+#define MG_ERR_INIT_STAT	0x101
+#define MG_ERR_TRANSLATION	0x102
+#define MG_ERR_CTRL_RST		0x103
+#define MG_ERR_INV_STAT		0x104
+#define MG_ERR_RSTOUT		0x105
+
+#define MG_MAX_ERRORS	6	/* Max read/write errors */
+
+/* command */
+#define MG_CMD_RD 0x20
+#define MG_CMD_WR 0x30
+#define MG_CMD_SLEEP 0x99
+#define MG_CMD_WAKEUP 0xC3
+#define MG_CMD_ID 0xEC
+#define MG_CMD_WR_CONF 0x3C
+#define MG_CMD_RD_CONF 0x40
+
+/* operation mode */
+#define MG_OP_CASCADE (1 << 0)
+#define MG_OP_CASCADE_SYNC_RD (1 << 1)
+#define MG_OP_CASCADE_SYNC_WR (1 << 2)
+#define MG_OP_INTERLEAVE (1 << 3)
+
+/* synchronous */
+#define MG_BURST_LAT_4 (3 << 4)
+#define MG_BURST_LAT_5 (4 << 4)
+#define MG_BURST_LAT_6 (5 << 4)
+#define MG_BURST_LAT_7 (6 << 4)
+#define MG_BURST_LAT_8 (7 << 4)
+#define MG_BURST_LEN_4 (1 << 1)
+#define MG_BURST_LEN_8 (2 << 1)
+#define MG_BURST_LEN_16 (3 << 1)
+#define MG_BURST_LEN_32 (4 << 1)
+#define MG_BURST_LEN_CONT (0 << 1)
+
+/* timeout value (unit: ms) */
+#define MG_TMAX_CONF_TO_CMD	1
+#define MG_TMAX_WAIT_RD_DRQ	10
+#define MG_TMAX_WAIT_WR_DRQ	500
+#define MG_TMAX_RST_TO_BUSY	10
+#define MG_TMAX_HDRST_TO_RDY	500
+#define MG_TMAX_SWRST_TO_RDY	500
+#define MG_TMAX_RSTOUT		3000
+
+#define MG_DEV_MASK (MG_BOOT_DEV | MG_STORAGE_DEV | MG_STORAGE_DEV_SKIP_RST)
+
+/* main structure for mflash driver */
+struct mg_host {
+	struct device *dev;
+
+	struct request_queue *breq;
+	struct request *req;
+	spinlock_t lock;
+	struct gendisk *gd;
+
+	struct timer_list timer;
+	void (*mg_do_intr) (struct mg_host *);
+
+	u16 id[ATA_ID_WORDS];
+
+	u16 cyls;
+	u16 heads;
+	u16 sectors;
+	u32 n_sectors;
+	u32 nres_sectors;
+
+	void __iomem *dev_base;
+	unsigned int irq;
+	unsigned int rst;
+	unsigned int rstout;
+
+	u32 major;
+	u32 error;
+};
+
+/*
+ * Debugging macro and defines
+ */
+#undef DO_MG_DEBUG
+#ifdef DO_MG_DEBUG
+#  define MG_DBG(fmt, args...) \
+	printk(KERN_DEBUG "%s:%d "fmt, __func__, __LINE__, ##args)
+#else /* CONFIG_MG_DEBUG */
+#  define MG_DBG(fmt, args...) do { } while (0)
+#endif /* CONFIG_MG_DEBUG */
+
+static void mg_request(struct request_queue *);
+
+static bool mg_end_request(struct mg_host *host, int err, unsigned int nr_bytes)
+{
+	if (__blk_end_request(host->req, err, nr_bytes))
+		return true;
+
+	host->req = NULL;
+	return false;
+}
+
+static bool mg_end_request_cur(struct mg_host *host, int err)
+{
+	return mg_end_request(host, err, blk_rq_cur_bytes(host->req));
+}
+
+static void mg_dump_status(const char *msg, unsigned int stat,
+		struct mg_host *host)
+{
+	char *name = MG_DISK_NAME;
+
+	if (host->req)
+		name = host->req->rq_disk->disk_name;
+
+	printk(KERN_ERR "%s: %s: status=0x%02x { ", name, msg, stat & 0xff);
+	if (stat & ATA_BUSY)
+		printk("Busy ");
+	if (stat & ATA_DRDY)
+		printk("DriveReady ");
+	if (stat & ATA_DF)
+		printk("WriteFault ");
+	if (stat & ATA_DSC)
+		printk("SeekComplete ");
+	if (stat & ATA_DRQ)
+		printk("DataRequest ");
+	if (stat & ATA_CORR)
+		printk("CorrectedError ");
+	if (stat & ATA_ERR)
+		printk("Error ");
+	printk("}\n");
+	if ((stat & ATA_ERR) == 0) {
+		host->error = 0;
+	} else {
+		host->error = inb((unsigned long)host->dev_base + MG_REG_ERROR);
+		printk(KERN_ERR "%s: %s: error=0x%02x { ", name, msg,
+				host->error & 0xff);
+		if (host->error & ATA_BBK)
+			printk("BadSector ");
+		if (host->error & ATA_UNC)
+			printk("UncorrectableError ");
+		if (host->error & ATA_IDNF)
+			printk("SectorIdNotFound ");
+		if (host->error & ATA_ABORTED)
+			printk("DriveStatusError ");
+		if (host->error & ATA_AMNF)
+			printk("AddrMarkNotFound ");
+		printk("}");
+		if (host->error & (ATA_BBK | ATA_UNC | ATA_IDNF | ATA_AMNF)) {
+			if (host->req)
+				printk(", sector=%u",
+				       (unsigned int)blk_rq_pos(host->req));
+		}
+		printk("\n");
+	}
+}
+
+static unsigned int mg_wait(struct mg_host *host, u32 expect, u32 msec)
+{
+	u8 status;
+	unsigned long expire, cur_jiffies;
+	struct mg_drv_data *prv_data = host->dev->platform_data;
+
+	host->error = MG_ERR_NONE;
+	expire = jiffies + msecs_to_jiffies(msec);
+
+	/* These 2 times dummy status read prevents reading invalid
+	 * status. A very little time (3 times of mflash operating clk)
+	 * is required for busy bit is set. Use dummy read instead of
+	 * busy wait, because mflash's PLL is machine dependent.
+	 */
+	if (prv_data->use_polling) {
+		status = inb((unsigned long)host->dev_base + MG_REG_STATUS);
+		status = inb((unsigned long)host->dev_base + MG_REG_STATUS);
+	}
+
+	status = inb((unsigned long)host->dev_base + MG_REG_STATUS);
+
+	do {
+		cur_jiffies = jiffies;
+		if (status & ATA_BUSY) {
+			if (expect == ATA_BUSY)
+				break;
+		} else {
+			/* Check the error condition! */
+			if (status & ATA_ERR) {
+				mg_dump_status("mg_wait", status, host);
+				break;
+			}
+
+			if (expect == MG_STAT_READY)
+				if (MG_READY_OK(status))
+					break;
+
+			if (expect == ATA_DRQ)
+				if (status & ATA_DRQ)
+					break;
+		}
+		if (!msec) {
+			mg_dump_status("not ready", status, host);
+			return MG_ERR_INV_STAT;
+		}
+
+		status = inb((unsigned long)host->dev_base + MG_REG_STATUS);
+	} while (time_before(cur_jiffies, expire));
+
+	if (time_after_eq(cur_jiffies, expire) && msec)
+		host->error = MG_ERR_TIMEOUT;
+
+	return host->error;
+}
+
+static unsigned int mg_wait_rstout(u32 rstout, u32 msec)
+{
+	unsigned long expire;
+
+	expire = jiffies + msecs_to_jiffies(msec);
+	while (time_before(jiffies, expire)) {
+		if (gpio_get_value(rstout) == 1)
+			return MG_ERR_NONE;
+		msleep(10);
+	}
+
+	return MG_ERR_RSTOUT;
+}
+
+static void mg_unexpected_intr(struct mg_host *host)
+{
+	u32 status = inb((unsigned long)host->dev_base + MG_REG_STATUS);
+
+	mg_dump_status("mg_unexpected_intr", status, host);
+}
+
+static irqreturn_t mg_irq(int irq, void *dev_id)
+{
+	struct mg_host *host = dev_id;
+	void (*handler)(struct mg_host *) = host->mg_do_intr;
+
+	spin_lock(&host->lock);
+
+	host->mg_do_intr = NULL;
+	del_timer(&host->timer);
+	if (!handler)
+		handler = mg_unexpected_intr;
+	handler(host);
+
+	spin_unlock(&host->lock);
+
+	return IRQ_HANDLED;
+}
+
+/* local copy of ata_id_string() */
+static void mg_id_string(const u16 *id, unsigned char *s,
+			 unsigned int ofs, unsigned int len)
+{
+	unsigned int c;
+
+	BUG_ON(len & 1);
+
+	while (len > 0) {
+		c = id[ofs] >> 8;
+		*s = c;
+		s++;
+
+		c = id[ofs] & 0xff;
+		*s = c;
+		s++;
+
+		ofs++;
+		len -= 2;
+	}
+}
+
+/* local copy of ata_id_c_string() */
+static void mg_id_c_string(const u16 *id, unsigned char *s,
+			   unsigned int ofs, unsigned int len)
+{
+	unsigned char *p;
+
+	mg_id_string(id, s, ofs, len - 1);
+
+	p = s + strnlen(s, len - 1);
+	while (p > s && p[-1] == ' ')
+		p--;
+	*p = '\0';
+}
+
+static int mg_get_disk_id(struct mg_host *host)
+{
+	u32 i;
+	s32 err;
+	const u16 *id = host->id;
+	struct mg_drv_data *prv_data = host->dev->platform_data;
+	char fwrev[ATA_ID_FW_REV_LEN + 1];
+	char model[ATA_ID_PROD_LEN + 1];
+	char serial[ATA_ID_SERNO_LEN + 1];
+
+	if (!prv_data->use_polling)
+		outb(ATA_NIEN, (unsigned long)host->dev_base + MG_REG_DRV_CTRL);
+
+	outb(MG_CMD_ID, (unsigned long)host->dev_base + MG_REG_COMMAND);
+	err = mg_wait(host, ATA_DRQ, MG_TMAX_WAIT_RD_DRQ);
+	if (err)
+		return err;
+
+	for (i = 0; i < (MG_SECTOR_SIZE >> 1); i++)
+		host->id[i] = le16_to_cpu(inw((unsigned long)host->dev_base +
+					MG_BUFF_OFFSET + i * 2));
+
+	outb(MG_CMD_RD_CONF, (unsigned long)host->dev_base + MG_REG_COMMAND);
+	err = mg_wait(host, MG_STAT_READY, MG_TMAX_CONF_TO_CMD);
+	if (err)
+		return err;
+
+	if ((id[ATA_ID_FIELD_VALID] & 1) == 0)
+		return MG_ERR_TRANSLATION;
+
+	host->n_sectors = ata_id_u32(id, ATA_ID_LBA_CAPACITY);
+	host->cyls = id[ATA_ID_CYLS];
+	host->heads = id[ATA_ID_HEADS];
+	host->sectors = id[ATA_ID_SECTORS];
+
+	if (MG_RES_SEC && host->heads && host->sectors) {
+		/* modify cyls, n_sectors */
+		host->cyls = (host->n_sectors - MG_RES_SEC) /
+			host->heads / host->sectors;
+		host->nres_sectors = host->n_sectors - host->cyls *
+			host->heads * host->sectors;
+		host->n_sectors -= host->nres_sectors;
+	}
+
+	mg_id_c_string(id, fwrev, ATA_ID_FW_REV, sizeof(fwrev));
+	mg_id_c_string(id, model, ATA_ID_PROD, sizeof(model));
+	mg_id_c_string(id, serial, ATA_ID_SERNO, sizeof(serial));
+	printk(KERN_INFO "mg_disk: model: %s\n", model);
+	printk(KERN_INFO "mg_disk: firm: %.8s\n", fwrev);
+	printk(KERN_INFO "mg_disk: serial: %s\n", serial);
+	printk(KERN_INFO "mg_disk: %d + reserved %d sectors\n",
+			host->n_sectors, host->nres_sectors);
+
+	if (!prv_data->use_polling)
+		outb(0, (unsigned long)host->dev_base + MG_REG_DRV_CTRL);
+
+	return err;
+}
+
+
+static int mg_disk_init(struct mg_host *host)
+{
+	struct mg_drv_data *prv_data = host->dev->platform_data;
+	s32 err;
+	u8 init_status;
+
+	/* hdd rst low */
+	gpio_set_value(host->rst, 0);
+	err = mg_wait(host, ATA_BUSY, MG_TMAX_RST_TO_BUSY);
+	if (err)
+		return err;
+
+	/* hdd rst high */
+	gpio_set_value(host->rst, 1);
+	err = mg_wait(host, MG_STAT_READY, MG_TMAX_HDRST_TO_RDY);
+	if (err)
+		return err;
+
+	/* soft reset on */
+	outb(ATA_SRST | (prv_data->use_polling ? ATA_NIEN : 0),
+			(unsigned long)host->dev_base + MG_REG_DRV_CTRL);
+	err = mg_wait(host, ATA_BUSY, MG_TMAX_RST_TO_BUSY);
+	if (err)
+		return err;
+
+	/* soft reset off */
+	outb(prv_data->use_polling ? ATA_NIEN : 0,
+			(unsigned long)host->dev_base + MG_REG_DRV_CTRL);
+	err = mg_wait(host, MG_STAT_READY, MG_TMAX_SWRST_TO_RDY);
+	if (err)
+		return err;
+
+	init_status = inb((unsigned long)host->dev_base + MG_REG_STATUS) & 0xf;
+
+	if (init_status == 0xf)
+		return MG_ERR_INIT_STAT;
+
+	return err;
+}
+
+static void mg_bad_rw_intr(struct mg_host *host)
+{
+	if (host->req)
+		if (++host->req->errors >= MG_MAX_ERRORS ||
+		    host->error == MG_ERR_TIMEOUT)
+			mg_end_request_cur(host, -EIO);
+}
+
+static unsigned int mg_out(struct mg_host *host,
+		unsigned int sect_num,
+		unsigned int sect_cnt,
+		unsigned int cmd,
+		void (*intr_addr)(struct mg_host *))
+{
+	struct mg_drv_data *prv_data = host->dev->platform_data;
+
+	if (mg_wait(host, MG_STAT_READY, MG_TMAX_CONF_TO_CMD))
+		return host->error;
+
+	if (!prv_data->use_polling) {
+		host->mg_do_intr = intr_addr;
+		mod_timer(&host->timer, jiffies + 3 * HZ);
+	}
+	if (MG_RES_SEC)
+		sect_num += MG_RES_SEC;
+	outb((u8)sect_cnt, (unsigned long)host->dev_base + MG_REG_SECT_CNT);
+	outb((u8)sect_num, (unsigned long)host->dev_base + MG_REG_SECT_NUM);
+	outb((u8)(sect_num >> 8), (unsigned long)host->dev_base +
+			MG_REG_CYL_LOW);
+	outb((u8)(sect_num >> 16), (unsigned long)host->dev_base +
+			MG_REG_CYL_HIGH);
+	outb((u8)((sect_num >> 24) | ATA_LBA | ATA_DEVICE_OBS),
+			(unsigned long)host->dev_base + MG_REG_DRV_HEAD);
+	outb(cmd, (unsigned long)host->dev_base + MG_REG_COMMAND);
+	return MG_ERR_NONE;
+}
+
+static void mg_read_one(struct mg_host *host, struct request *req)
+{
+	u16 *buff = (u16 *)bio_data(req->bio);
+	u32 i;
+
+	for (i = 0; i < MG_SECTOR_SIZE >> 1; i++)
+		*buff++ = inw((unsigned long)host->dev_base + MG_BUFF_OFFSET +
+			      (i << 1));
+}
+
+static void mg_read(struct request *req)
+{
+	struct mg_host *host = req->rq_disk->private_data;
+
+	if (mg_out(host, blk_rq_pos(req), blk_rq_sectors(req),
+		   MG_CMD_RD, NULL) != MG_ERR_NONE)
+		mg_bad_rw_intr(host);
+
+	MG_DBG("requested %d sects (from %ld), buffer=0x%p\n",
+	       blk_rq_sectors(req), blk_rq_pos(req), bio_data(req->bio));
+
+	do {
+		if (mg_wait(host, ATA_DRQ,
+			    MG_TMAX_WAIT_RD_DRQ) != MG_ERR_NONE) {
+			mg_bad_rw_intr(host);
+			return;
+		}
+
+		mg_read_one(host, req);
+
+		outb(MG_CMD_RD_CONF, (unsigned long)host->dev_base +
+				MG_REG_COMMAND);
+	} while (mg_end_request(host, 0, MG_SECTOR_SIZE));
+}
+
+static void mg_write_one(struct mg_host *host, struct request *req)
+{
+	u16 *buff = (u16 *)bio_data(req->bio);
+	u32 i;
+
+	for (i = 0; i < MG_SECTOR_SIZE >> 1; i++)
+		outw(*buff++, (unsigned long)host->dev_base + MG_BUFF_OFFSET +
+		     (i << 1));
+}
+
+static void mg_write(struct request *req)
+{
+	struct mg_host *host = req->rq_disk->private_data;
+	unsigned int rem = blk_rq_sectors(req);
+
+	if (mg_out(host, blk_rq_pos(req), rem,
+		   MG_CMD_WR, NULL) != MG_ERR_NONE) {
+		mg_bad_rw_intr(host);
+		return;
+	}
+
+	MG_DBG("requested %d sects (from %ld), buffer=0x%p\n",
+	       rem, blk_rq_pos(req), bio_data(req->bio));
+
+	if (mg_wait(host, ATA_DRQ,
+		    MG_TMAX_WAIT_WR_DRQ) != MG_ERR_NONE) {
+		mg_bad_rw_intr(host);
+		return;
+	}
+
+	do {
+		mg_write_one(host, req);
+
+		outb(MG_CMD_WR_CONF, (unsigned long)host->dev_base +
+				MG_REG_COMMAND);
+
+		rem--;
+		if (rem > 1 && mg_wait(host, ATA_DRQ,
+					MG_TMAX_WAIT_WR_DRQ) != MG_ERR_NONE) {
+			mg_bad_rw_intr(host);
+			return;
+		} else if (mg_wait(host, MG_STAT_READY,
+					MG_TMAX_WAIT_WR_DRQ) != MG_ERR_NONE) {
+			mg_bad_rw_intr(host);
+			return;
+		}
+	} while (mg_end_request(host, 0, MG_SECTOR_SIZE));
+}
+
+static void mg_read_intr(struct mg_host *host)
+{
+	struct request *req = host->req;
+	u32 i;
+
+	/* check status */
+	do {
+		i = inb((unsigned long)host->dev_base + MG_REG_STATUS);
+		if (i & ATA_BUSY)
+			break;
+		if (!MG_READY_OK(i))
+			break;
+		if (i & ATA_DRQ)
+			goto ok_to_read;
+	} while (0);
+	mg_dump_status("mg_read_intr", i, host);
+	mg_bad_rw_intr(host);
+	mg_request(host->breq);
+	return;
+
+ok_to_read:
+	mg_read_one(host, req);
+
+	MG_DBG("sector %ld, remaining=%ld, buffer=0x%p\n",
+	       blk_rq_pos(req), blk_rq_sectors(req) - 1, bio_data(req->bio));
+
+	/* send read confirm */
+	outb(MG_CMD_RD_CONF, (unsigned long)host->dev_base + MG_REG_COMMAND);
+
+	if (mg_end_request(host, 0, MG_SECTOR_SIZE)) {
+		/* set handler if read remains */
+		host->mg_do_intr = mg_read_intr;
+		mod_timer(&host->timer, jiffies + 3 * HZ);
+	} else /* goto next request */
+		mg_request(host->breq);
+}
+
+static void mg_write_intr(struct mg_host *host)
+{
+	struct request *req = host->req;
+	u32 i;
+	bool rem;
+
+	/* check status */
+	do {
+		i = inb((unsigned long)host->dev_base + MG_REG_STATUS);
+		if (i & ATA_BUSY)
+			break;
+		if (!MG_READY_OK(i))
+			break;
+		if ((blk_rq_sectors(req) <= 1) || (i & ATA_DRQ))
+			goto ok_to_write;
+	} while (0);
+	mg_dump_status("mg_write_intr", i, host);
+	mg_bad_rw_intr(host);
+	mg_request(host->breq);
+	return;
+
+ok_to_write:
+	if ((rem = mg_end_request(host, 0, MG_SECTOR_SIZE))) {
+		/* write 1 sector and set handler if remains */
+		mg_write_one(host, req);
+		MG_DBG("sector %ld, remaining=%ld, buffer=0x%p\n",
+		       blk_rq_pos(req), blk_rq_sectors(req), bio_data(req->bio));
+		host->mg_do_intr = mg_write_intr;
+		mod_timer(&host->timer, jiffies + 3 * HZ);
+	}
+
+	/* send write confirm */
+	outb(MG_CMD_WR_CONF, (unsigned long)host->dev_base + MG_REG_COMMAND);
+
+	if (!rem)
+		mg_request(host->breq);
+}
+
+static void mg_times_out(unsigned long data)
+{
+	struct mg_host *host = (struct mg_host *)data;
+	char *name;
+
+	spin_lock_irq(&host->lock);
+
+	if (!host->req)
+		goto out_unlock;
+
+	host->mg_do_intr = NULL;
+
+	name = host->req->rq_disk->disk_name;
+	printk(KERN_DEBUG "%s: timeout\n", name);
+
+	host->error = MG_ERR_TIMEOUT;
+	mg_bad_rw_intr(host);
+
+out_unlock:
+	mg_request(host->breq);
+	spin_unlock_irq(&host->lock);
+}
+
+static void mg_request_poll(struct request_queue *q)
+{
+	struct mg_host *host = q->queuedata;
+
+	while (1) {
+		if (!host->req) {
+			host->req = blk_fetch_request(q);
+			if (!host->req)
+				break;
+		}
+
+		if (unlikely(host->req->cmd_type != REQ_TYPE_FS)) {
+			mg_end_request_cur(host, -EIO);
+			continue;
+		}
+
+		if (rq_data_dir(host->req) == READ)
+			mg_read(host->req);
+		else
+			mg_write(host->req);
+	}
+}
+
+static unsigned int mg_issue_req(struct request *req,
+		struct mg_host *host,
+		unsigned int sect_num,
+		unsigned int sect_cnt)
+{
+	switch (rq_data_dir(req)) {
+	case READ:
+		if (mg_out(host, sect_num, sect_cnt, MG_CMD_RD, &mg_read_intr)
+				!= MG_ERR_NONE) {
+			mg_bad_rw_intr(host);
+			return host->error;
+		}
+		break;
+	case WRITE:
+		/* TODO : handler */
+		outb(ATA_NIEN, (unsigned long)host->dev_base + MG_REG_DRV_CTRL);
+		if (mg_out(host, sect_num, sect_cnt, MG_CMD_WR, &mg_write_intr)
+				!= MG_ERR_NONE) {
+			mg_bad_rw_intr(host);
+			return host->error;
+		}
+		del_timer(&host->timer);
+		mg_wait(host, ATA_DRQ, MG_TMAX_WAIT_WR_DRQ);
+		outb(0, (unsigned long)host->dev_base + MG_REG_DRV_CTRL);
+		if (host->error) {
+			mg_bad_rw_intr(host);
+			return host->error;
+		}
+		mg_write_one(host, req);
+		mod_timer(&host->timer, jiffies + 3 * HZ);
+		outb(MG_CMD_WR_CONF, (unsigned long)host->dev_base +
+				MG_REG_COMMAND);
+		break;
+	}
+	return MG_ERR_NONE;
+}
+
+/* This function also called from IRQ context */
+static void mg_request(struct request_queue *q)
+{
+	struct mg_host *host = q->queuedata;
+	struct request *req;
+	u32 sect_num, sect_cnt;
+
+	while (1) {
+		if (!host->req) {
+			host->req = blk_fetch_request(q);
+			if (!host->req)
+				break;
+		}
+		req = host->req;
+
+		/* check unwanted request call */
+		if (host->mg_do_intr)
+			return;
+
+		del_timer(&host->timer);
+
+		sect_num = blk_rq_pos(req);
+		/* deal whole segments */
+		sect_cnt = blk_rq_sectors(req);
+
+		/* sanity check */
+		if (sect_num >= get_capacity(req->rq_disk) ||
+				((sect_num + sect_cnt) >
+				 get_capacity(req->rq_disk))) {
+			printk(KERN_WARNING
+					"%s: bad access: sector=%d, count=%d\n",
+					req->rq_disk->disk_name,
+					sect_num, sect_cnt);
+			mg_end_request_cur(host, -EIO);
+			continue;
+		}
+
+		if (unlikely(req->cmd_type != REQ_TYPE_FS)) {
+			mg_end_request_cur(host, -EIO);
+			continue;
+		}
+
+		if (!mg_issue_req(req, host, sect_num, sect_cnt))
+			return;
+	}
+}
+
+static int mg_getgeo(struct block_device *bdev, struct hd_geometry *geo)
+{
+	struct mg_host *host = bdev->bd_disk->private_data;
+
+	geo->cylinders = (unsigned short)host->cyls;
+	geo->heads = (unsigned char)host->heads;
+	geo->sectors = (unsigned char)host->sectors;
+	return 0;
+}
+
+static const struct block_device_operations mg_disk_ops = {
+	.getgeo = mg_getgeo
+};
+
+#ifdef CONFIG_PM_SLEEP
+static int mg_suspend(struct device *dev)
+{
+	struct mg_drv_data *prv_data = dev->platform_data;
+	struct mg_host *host = prv_data->host;
+
+	if (mg_wait(host, MG_STAT_READY, MG_TMAX_CONF_TO_CMD))
+		return -EIO;
+
+	if (!prv_data->use_polling)
+		outb(ATA_NIEN, (unsigned long)host->dev_base + MG_REG_DRV_CTRL);
+
+	outb(MG_CMD_SLEEP, (unsigned long)host->dev_base + MG_REG_COMMAND);
+	/* wait until mflash deep sleep */
+	msleep(1);
+
+	if (mg_wait(host, MG_STAT_READY, MG_TMAX_CONF_TO_CMD)) {
+		if (!prv_data->use_polling)
+			outb(0, (unsigned long)host->dev_base + MG_REG_DRV_CTRL);
+		return -EIO;
+	}
+
+	return 0;
+}
+
+static int mg_resume(struct device *dev)
+{
+	struct mg_drv_data *prv_data = dev->platform_data;
+	struct mg_host *host = prv_data->host;
+
+	if (mg_wait(host, MG_STAT_READY, MG_TMAX_CONF_TO_CMD))
+		return -EIO;
+
+	outb(MG_CMD_WAKEUP, (unsigned long)host->dev_base + MG_REG_COMMAND);
+	/* wait until mflash wakeup */
+	msleep(1);
+
+	if (mg_wait(host, MG_STAT_READY, MG_TMAX_CONF_TO_CMD))
+		return -EIO;
+
+	if (!prv_data->use_polling)
+		outb(0, (unsigned long)host->dev_base + MG_REG_DRV_CTRL);
+
+	return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(mg_pm, mg_suspend, mg_resume);
+
+static int mg_probe(struct platform_device *plat_dev)
+{
+	struct mg_host *host;
+	struct resource *rsc;
+	struct mg_drv_data *prv_data = plat_dev->dev.platform_data;
+	int err = 0;
+
+	if (!prv_data) {
+		printk(KERN_ERR	"%s:%d fail (no driver_data)\n",
+				__func__, __LINE__);
+		err = -EINVAL;
+		goto probe_err;
+	}
+
+	/* alloc mg_host */
+	host = kzalloc(sizeof(struct mg_host), GFP_KERNEL);
+	if (!host) {
+		printk(KERN_ERR "%s:%d fail (no memory for mg_host)\n",
+				__func__, __LINE__);
+		err = -ENOMEM;
+		goto probe_err;
+	}
+	host->major = MG_DISK_MAJ;
+
+	/* link each other */
+	prv_data->host = host;
+	host->dev = &plat_dev->dev;
+
+	/* io remap */
+	rsc = platform_get_resource(plat_dev, IORESOURCE_MEM, 0);
+	if (!rsc) {
+		printk(KERN_ERR "%s:%d platform_get_resource fail\n",
+				__func__, __LINE__);
+		err = -EINVAL;
+		goto probe_err_2;
+	}
+	host->dev_base = ioremap(rsc->start, resource_size(rsc));
+	if (!host->dev_base) {
+		printk(KERN_ERR "%s:%d ioremap fail\n",
+				__func__, __LINE__);
+		err = -EIO;
+		goto probe_err_2;
+	}
+	MG_DBG("dev_base = 0x%x\n", (u32)host->dev_base);
+
+	/* get reset pin */
+	rsc = platform_get_resource_byname(plat_dev, IORESOURCE_IO,
+			MG_RST_PIN);
+	if (!rsc) {
+		printk(KERN_ERR "%s:%d get reset pin fail\n",
+				__func__, __LINE__);
+		err = -EIO;
+		goto probe_err_3;
+	}
+	host->rst = rsc->start;
+
+	/* init rst pin */
+	err = gpio_request(host->rst, MG_RST_PIN);
+	if (err)
+		goto probe_err_3;
+	gpio_direction_output(host->rst, 1);
+
+	/* reset out pin */
+	if (!(prv_data->dev_attr & MG_DEV_MASK)) {
+		err = -EINVAL;
+		goto probe_err_3a;
+	}
+
+	if (prv_data->dev_attr != MG_BOOT_DEV) {
+		rsc = platform_get_resource_byname(plat_dev, IORESOURCE_IO,
+				MG_RSTOUT_PIN);
+		if (!rsc) {
+			printk(KERN_ERR "%s:%d get reset-out pin fail\n",
+					__func__, __LINE__);
+			err = -EIO;
+			goto probe_err_3a;
+		}
+		host->rstout = rsc->start;
+		err = gpio_request(host->rstout, MG_RSTOUT_PIN);
+		if (err)
+			goto probe_err_3a;
+		gpio_direction_input(host->rstout);
+	}
+
+	/* disk reset */
+	if (prv_data->dev_attr == MG_STORAGE_DEV) {
+		/* If POR seq. not yet finished, wait */
+		err = mg_wait_rstout(host->rstout, MG_TMAX_RSTOUT);
+		if (err)
+			goto probe_err_3b;
+		err = mg_disk_init(host);
+		if (err) {
+			printk(KERN_ERR "%s:%d fail (err code : %d)\n",
+					__func__, __LINE__, err);
+			err = -EIO;
+			goto probe_err_3b;
+		}
+	}
+
+	/* get irq resource */
+	if (!prv_data->use_polling) {
+		host->irq = platform_get_irq(plat_dev, 0);
+		if (host->irq == -ENXIO) {
+			err = host->irq;
+			goto probe_err_3b;
+		}
+		err = request_irq(host->irq, mg_irq,
+				IRQF_TRIGGER_RISING,
+				MG_DEV_NAME, host);
+		if (err) {
+			printk(KERN_ERR "%s:%d fail (request_irq err=%d)\n",
+					__func__, __LINE__, err);
+			goto probe_err_3b;
+		}
+
+	}
+
+	/* get disk id */
+	err = mg_get_disk_id(host);
+	if (err) {
+		printk(KERN_ERR "%s:%d fail (err code : %d)\n",
+				__func__, __LINE__, err);
+		err = -EIO;
+		goto probe_err_4;
+	}
+
+	err = register_blkdev(host->major, MG_DISK_NAME);
+	if (err < 0) {
+		printk(KERN_ERR "%s:%d register_blkdev fail (err code : %d)\n",
+				__func__, __LINE__, err);
+		goto probe_err_4;
+	}
+	if (!host->major)
+		host->major = err;
+
+	spin_lock_init(&host->lock);
+
+	if (prv_data->use_polling)
+		host->breq = blk_init_queue(mg_request_poll, &host->lock);
+	else
+		host->breq = blk_init_queue(mg_request, &host->lock);
+
+	if (!host->breq) {
+		err = -ENOMEM;
+		printk(KERN_ERR "%s:%d (blk_init_queue) fail\n",
+				__func__, __LINE__);
+		goto probe_err_5;
+	}
+	host->breq->queuedata = host;
+
+	/* mflash is random device, thanx for the noop */
+	err = elevator_change(host->breq, "noop");
+	if (err) {
+		printk(KERN_ERR "%s:%d (elevator_init) fail\n",
+				__func__, __LINE__);
+		goto probe_err_6;
+	}
+	blk_queue_max_hw_sectors(host->breq, MG_MAX_SECTS);
+	blk_queue_logical_block_size(host->breq, MG_SECTOR_SIZE);
+
+	init_timer(&host->timer);
+	host->timer.function = mg_times_out;
+	host->timer.data = (unsigned long)host;
+
+	host->gd = alloc_disk(MG_DISK_MAX_PART);
+	if (!host->gd) {
+		printk(KERN_ERR "%s:%d (alloc_disk) fail\n",
+				__func__, __LINE__);
+		err = -ENOMEM;
+		goto probe_err_7;
+	}
+	host->gd->major = host->major;
+	host->gd->first_minor = 0;
+	host->gd->fops = &mg_disk_ops;
+	host->gd->queue = host->breq;
+	host->gd->private_data = host;
+	sprintf(host->gd->disk_name, MG_DISK_NAME"a");
+
+	set_capacity(host->gd, host->n_sectors);
+
+	add_disk(host->gd);
+
+	return err;
+
+probe_err_7:
+	del_timer_sync(&host->timer);
+probe_err_6:
+	blk_cleanup_queue(host->breq);
+probe_err_5:
+	unregister_blkdev(MG_DISK_MAJ, MG_DISK_NAME);
+probe_err_4:
+	if (!prv_data->use_polling)
+		free_irq(host->irq, host);
+probe_err_3b:
+	gpio_free(host->rstout);
+probe_err_3a:
+	gpio_free(host->rst);
+probe_err_3:
+	iounmap(host->dev_base);
+probe_err_2:
+	kfree(host);
+probe_err:
+	return err;
+}
+
+static int mg_remove(struct platform_device *plat_dev)
+{
+	struct mg_drv_data *prv_data = plat_dev->dev.platform_data;
+	struct mg_host *host = prv_data->host;
+	int err = 0;
+
+	/* delete timer */
+	del_timer_sync(&host->timer);
+
+	/* remove disk */
+	if (host->gd) {
+		del_gendisk(host->gd);
+		put_disk(host->gd);
+	}
+	/* remove queue */
+	if (host->breq)
+		blk_cleanup_queue(host->breq);
+
+	/* unregister blk device */
+	unregister_blkdev(host->major, MG_DISK_NAME);
+
+	/* free irq */
+	if (!prv_data->use_polling)
+		free_irq(host->irq, host);
+
+	/* free reset-out pin */
+	if (prv_data->dev_attr != MG_BOOT_DEV)
+		gpio_free(host->rstout);
+
+	/* free rst pin */
+	if (host->rst)
+		gpio_free(host->rst);
+
+	/* unmap io */
+	if (host->dev_base)
+		iounmap(host->dev_base);
+
+	/* free mg_host */
+	kfree(host);
+
+	return err;
+}
+
+static struct platform_driver mg_disk_driver = {
+	.probe = mg_probe,
+	.remove = mg_remove,
+	.driver = {
+		.name = MG_DEV_NAME,
+		.pm = &mg_pm,
+	}
+};
+
+/****************************************************************************
+ *
+ * Module stuff
+ *
+ ****************************************************************************/
+
+static int __init mg_init(void)
+{
+	printk(KERN_INFO "mGine mflash driver, (c) 2008 mGine Co.\n");
+	return platform_driver_register(&mg_disk_driver);
+}
+
+static void __exit mg_exit(void)
+{
+	printk(KERN_INFO "mflash driver : bye bye\n");
+	platform_driver_unregister(&mg_disk_driver);
+}
+
+module_init(mg_init);
+module_exit(mg_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("unsik Kim <donari75@gmail.com>");
+MODULE_DESCRIPTION("mGine m[g]flash device driver");