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-rw-r--r--Documentation/blockdev/00-INDEX2
-rw-r--r--Documentation/blockdev/mflash.txt84
-rw-r--r--drivers/block/Kconfig17
-rw-r--r--drivers/block/Makefile1
-rw-r--r--drivers/block/mg_disk.c1005
-rw-r--r--include/linux/mg_disk.h206
6 files changed, 1315 insertions, 0 deletions
diff --git a/Documentation/blockdev/00-INDEX b/Documentation/blockdev/00-INDEX
index 86f054c..c08df56 100644
--- a/Documentation/blockdev/00-INDEX
+++ b/Documentation/blockdev/00-INDEX
@@ -8,6 +8,8 @@ cpqarray.txt
- info on using Compaq's SMART2 Intelligent Disk Array Controllers.
floppy.txt
- notes and driver options for the floppy disk driver.
+mflash.txt
+ - info on mGine m(g)flash driver for linux.
nbd.txt
- info on a TCP implementation of a network block device.
paride.txt
diff --git a/Documentation/blockdev/mflash.txt b/Documentation/blockdev/mflash.txt
new file mode 100644
index 0000000..1f610ec
--- /dev/null
+++ b/Documentation/blockdev/mflash.txt
@@ -0,0 +1,84 @@
+This document describes m[g]flash support in linux.
+
+Contents
+ 1. Overview
+ 2. Reserved area configuration
+ 3. Example of mflash platform driver registration
+
+1. Overview
+
+Mflash and gflash are embedded flash drive. The only difference is mflash is
+MCP(Multi Chip Package) device. These two device operate exactly same way.
+So the rest mflash repersents mflash and gflash altogether.
+
+Internally, mflash has nand flash and other hardware logics and supports
+2 different operation (ATA, IO) modes. ATA mode doesn't need any new
+driver and currently works well under standard IDE subsystem. Actually it's
+one chip SSD. IO mode is ATA-like custom mode for the host that doesn't have
+IDE interface.
+
+Followings are brief descriptions about IO mode.
+A. IO mode based on ATA protocol and uses some custom command. (read confirm,
+write confirm)
+B. IO mode uses SRAM bus interface.
+C. IO mode supports 4kB boot area, so host can boot from mflash.
+
+2. Reserved area configuration
+If host boot from mflash, usually needs raw area for boot loader image. All of
+the mflash's block device operation will be taken this value as start offset.
+Note that boot loader's size of reserved area and kernel configuration value
+must be same.
+
+3. Example of mflash platform driver registration
+Working mflash is very straight forward. Adding platform device stuff to board
+configuration file is all. Here is some pseudo example.
+
+static struct mg_drv_data mflash_drv_data = {
+ /* If you want to polling driver set to 1 */
+ .use_polling = 0,
+ /* device attribution */
+ .dev_attr = MG_BOOT_DEV
+};
+
+static struct resource mg_mflash_rsc[] = {
+ /* Base address of mflash */
+ [0] = {
+ .start = 0x08000000,
+ .end = 0x08000000 + SZ_64K - 1,
+ .flags = IORESOURCE_MEM
+ },
+ /* mflash interrupt pin */
+ [1] = {
+ .start = IRQ_GPIO(84),
+ .end = IRQ_GPIO(84),
+ .flags = IORESOURCE_IRQ
+ },
+ /* mflash reset pin */
+ [2] = {
+ .start = 43,
+ .end = 43,
+ .name = MG_RST_PIN,
+ .flags = IORESOURCE_IO
+ },
+ /* mflash reset-out pin
+ * If you use mflash as storage device (i.e. other than MG_BOOT_DEV),
+ * should assign this */
+ [3] = {
+ .start = 51,
+ .end = 51,
+ .name = MG_RSTOUT_PIN,
+ .flags = IORESOURCE_IO
+ }
+};
+
+static struct platform_device mflash_dev = {
+ .name = MG_DEV_NAME,
+ .id = -1,
+ .dev = {
+ .platform_data = &mflash_drv_data,
+ },
+ .num_resources = ARRAY_SIZE(mg_mflash_rsc),
+ .resource = mg_mflash_rsc
+};
+
+platform_device_register(&mflash_dev);
diff --git a/drivers/block/Kconfig b/drivers/block/Kconfig
index e7b8aa0..ddea8e4 100644
--- a/drivers/block/Kconfig
+++ b/drivers/block/Kconfig
@@ -410,6 +410,23 @@ config ATA_OVER_ETH
This driver provides Support for ATA over Ethernet block
devices like the Coraid EtherDrive (R) Storage Blade.
+config MG_DISK
+ tristate "mGine mflash, gflash support"
+ depends on ARM && ATA && GPIOLIB
+ help
+ mGine mFlash(gFlash) block device driver
+
+config MG_DISK_RES
+ int "Size of reserved area before MBR"
+ depends on MG_DISK
+ default 0
+ help
+ Define size of reserved area that usually used for boot. Unit is KB.
+ All of the block device operation will be taken this value as start
+ offset
+ Examples:
+ 1024 => 1 MB
+
config SUNVDC
tristate "Sun Virtual Disk Client support"
depends on SUN_LDOMS
diff --git a/drivers/block/Makefile b/drivers/block/Makefile
index 3145141..7755a5e 100644
--- a/drivers/block/Makefile
+++ b/drivers/block/Makefile
@@ -21,6 +21,7 @@ obj-$(CONFIG_BLK_CPQ_CISS_DA) += cciss.o
obj-$(CONFIG_BLK_DEV_DAC960) += DAC960.o
obj-$(CONFIG_XILINX_SYSACE) += xsysace.o
obj-$(CONFIG_CDROM_PKTCDVD) += pktcdvd.o
+obj-$(CONFIG_MG_DISK) += mg_disk.o
obj-$(CONFIG_SUNVDC) += sunvdc.o
obj-$(CONFIG_BLK_DEV_UMEM) += umem.o
diff --git a/drivers/block/mg_disk.c b/drivers/block/mg_disk.c
new file mode 100644
index 0000000..fb39d9a
--- /dev/null
+++ b/drivers/block/mg_disk.c
@@ -0,0 +1,1005 @@
+/*
+ * 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/libata.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/platform_device.h>
+#include <linux/gpio.h>
+#include <linux/mg_disk.h>
+
+#define MG_RES_SEC (CONFIG_MG_DISK_RES << 1)
+
+static void mg_request(struct request_queue *);
+
+static void mg_dump_status(const char *msg, unsigned int stat,
+ struct mg_host *host)
+{
+ char *name = MG_DISK_NAME;
+ struct request *req;
+
+ if (host->breq) {
+ req = elv_next_request(host->breq);
+ if (req)
+ name = req->rq_disk->disk_name;
+ }
+
+ printk(KERN_ERR "%s: %s: status=0x%02x { ", name, msg, stat & 0xff);
+ if (stat & MG_REG_STATUS_BIT_BUSY)
+ printk("Busy ");
+ if (stat & MG_REG_STATUS_BIT_READY)
+ printk("DriveReady ");
+ if (stat & MG_REG_STATUS_BIT_WRITE_FAULT)
+ printk("WriteFault ");
+ if (stat & MG_REG_STATUS_BIT_SEEK_DONE)
+ printk("SeekComplete ");
+ if (stat & MG_REG_STATUS_BIT_DATA_REQ)
+ printk("DataRequest ");
+ if (stat & MG_REG_STATUS_BIT_CORRECTED_ERROR)
+ printk("CorrectedError ");
+ if (stat & MG_REG_STATUS_BIT_ERROR)
+ printk("Error ");
+ printk("}\n");
+ if ((stat & MG_REG_STATUS_BIT_ERROR) == 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 & MG_REG_ERR_BBK)
+ printk("BadSector ");
+ if (host->error & MG_REG_ERR_UNC)
+ printk("UncorrectableError ");
+ if (host->error & MG_REG_ERR_IDNF)
+ printk("SectorIdNotFound ");
+ if (host->error & MG_REG_ERR_ABRT)
+ printk("DriveStatusError ");
+ if (host->error & MG_REG_ERR_AMNF)
+ printk("AddrMarkNotFound ");
+ printk("}");
+ if (host->error &
+ (MG_REG_ERR_BBK | MG_REG_ERR_UNC |
+ MG_REG_ERR_IDNF | MG_REG_ERR_AMNF)) {
+ if (host->breq) {
+ req = elv_next_request(host->breq);
+ if (req)
+ printk(", sector=%ld", req->sector);
+ }
+
+ }
+ 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);
+
+ status = inb((unsigned long)host->dev_base + MG_REG_STATUS);
+
+ do {
+ cur_jiffies = jiffies;
+ if (status & MG_REG_STATUS_BIT_BUSY) {
+ if (expect == MG_REG_STATUS_BIT_BUSY)
+ break;
+ } else {
+ /* Check the error condition! */
+ if (status & MG_REG_STATUS_BIT_ERROR) {
+ mg_dump_status("mg_wait", status, host);
+ break;
+ }
+
+ if (expect == MG_STAT_READY)
+ if (MG_READY_OK(status))
+ break;
+
+ if (expect == MG_REG_STATUS_BIT_DATA_REQ)
+ if (status & MG_REG_STATUS_BIT_DATA_REQ)
+ break;
+ }
+ if (!msec) {
+ mg_dump_status("not ready", status, host);
+ return MG_ERR_INV_STAT;
+ }
+ if (prv_data->use_polling)
+ msleep(1);
+
+ 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;
+
+ host->mg_do_intr = 0;
+ del_timer(&host->timer);
+ if (!handler)
+ handler = mg_unexpected_intr;
+ handler(host);
+ return IRQ_HANDLED;
+}
+
+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(MG_REG_CTRL_INTR_DISABLE,
+ (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, MG_REG_STATUS_BIT_DATA_REQ, 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;
+ }
+
+ ata_id_c_string(id, fwrev, ATA_ID_FW_REV, sizeof(fwrev));
+ ata_id_c_string(id, model, ATA_ID_PROD, sizeof(model));
+ ata_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(MG_REG_CTRL_INTR_ENABLE, (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, MG_REG_STATUS_BIT_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(MG_REG_CTRL_RESET |
+ (prv_data->use_polling ? MG_REG_CTRL_INTR_DISABLE :
+ MG_REG_CTRL_INTR_ENABLE),
+ (unsigned long)host->dev_base + MG_REG_DRV_CTRL);
+ err = mg_wait(host, MG_REG_STATUS_BIT_BUSY, MG_TMAX_RST_TO_BUSY);
+ if (err)
+ return err;
+
+ /* soft reset off */
+ outb(prv_data->use_polling ? MG_REG_CTRL_INTR_DISABLE :
+ MG_REG_CTRL_INTR_ENABLE,
+ (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)
+{
+ struct request *req = elv_next_request(host->breq);
+ if (req != NULL)
+ if (++req->errors >= MG_MAX_ERRORS ||
+ host->error == MG_ERR_TIMEOUT)
+ end_request(req, 0);
+}
+
+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) | MG_REG_HEAD_LBA_MODE),
+ (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(struct request *req)
+{
+ u32 remains, j;
+ struct mg_host *host = req->rq_disk->private_data;
+
+ remains = req->nr_sectors;
+
+ if (mg_out(host, req->sector, req->nr_sectors, MG_CMD_RD, 0) !=
+ MG_ERR_NONE)
+ mg_bad_rw_intr(host);
+
+ MG_DBG("requested %d sects (from %ld), buffer=0x%p\n",
+ remains, req->sector, req->buffer);
+
+ while (remains) {
+ if (mg_wait(host, MG_REG_STATUS_BIT_DATA_REQ,
+ MG_TMAX_WAIT_RD_DRQ) != MG_ERR_NONE) {
+ mg_bad_rw_intr(host);
+ return;
+ }
+ for (j = 0; j < MG_SECTOR_SIZE >> 1; j++) {
+ *(u16 *)req->buffer =
+ inw((unsigned long)host->dev_base +
+ MG_BUFF_OFFSET + (j << 1));
+ req->buffer += 2;
+ }
+
+ req->sector++;
+ req->errors = 0;
+ remains = --req->nr_sectors;
+ --req->current_nr_sectors;
+
+ if (req->current_nr_sectors <= 0) {
+ MG_DBG("remain : %d sects\n", remains);
+ end_request(req, 1);
+ if (remains > 0)
+ req = elv_next_request(host->breq);
+ }
+
+ outb(MG_CMD_RD_CONF, (unsigned long)host->dev_base +
+ MG_REG_COMMAND);
+ }
+}
+
+static void mg_write(struct request *req)
+{
+ u32 remains, j;
+ struct mg_host *host = req->rq_disk->private_data;
+
+ remains = req->nr_sectors;
+
+ if (mg_out(host, req->sector, req->nr_sectors, MG_CMD_WR, 0) !=
+ MG_ERR_NONE) {
+ mg_bad_rw_intr(host);
+ return;
+ }
+
+
+ MG_DBG("requested %d sects (from %ld), buffer=0x%p\n",
+ remains, req->sector, req->buffer);
+ while (remains) {
+ if (mg_wait(host, MG_REG_STATUS_BIT_DATA_REQ,
+ MG_TMAX_WAIT_WR_DRQ) != MG_ERR_NONE) {
+ mg_bad_rw_intr(host);
+ return;
+ }
+ for (j = 0; j < MG_SECTOR_SIZE >> 1; j++) {
+ outw(*(u16 *)req->buffer,
+ (unsigned long)host->dev_base +
+ MG_BUFF_OFFSET + (j << 1));
+ req->buffer += 2;
+ }
+ req->sector++;
+ remains = --req->nr_sectors;
+ --req->current_nr_sectors;
+
+ if (req->current_nr_sectors <= 0) {
+ MG_DBG("remain : %d sects\n", remains);
+ end_request(req, 1);
+ if (remains > 0)
+ req = elv_next_request(host->breq);
+ }
+
+ outb(MG_CMD_WR_CONF, (unsigned long)host->dev_base +
+ MG_REG_COMMAND);
+ }
+}
+
+static void mg_read_intr(struct mg_host *host)
+{
+ u32 i;
+ struct request *req;
+
+ /* check status */
+ do {
+ i = inb((unsigned long)host->dev_base + MG_REG_STATUS);
+ if (i & MG_REG_STATUS_BIT_BUSY)
+ break;
+ if (!MG_READY_OK(i))
+ break;
+ if (i & MG_REG_STATUS_BIT_DATA_REQ)
+ 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:
+ /* get current segment of request */
+ req = elv_next_request(host->breq);
+
+ /* read 1 sector */
+ for (i = 0; i < MG_SECTOR_SIZE >> 1; i++) {
+ *(u16 *)req->buffer =
+ inw((unsigned long)host->dev_base + MG_BUFF_OFFSET +
+ (i << 1));
+ req->buffer += 2;
+ }
+
+ /* manipulate request */
+ MG_DBG("sector %ld, remaining=%ld, buffer=0x%p\n",
+ req->sector, req->nr_sectors - 1, req->buffer);
+
+ req->sector++;
+ req->errors = 0;
+ i = --req->nr_sectors;
+ --req->current_nr_sectors;
+
+ /* let know if current segment done */
+ if (req->current_nr_sectors <= 0)
+ end_request(req, 1);
+
+ /* set handler if read remains */
+ if (i > 0) {
+ host->mg_do_intr = mg_read_intr;
+ mod_timer(&host->timer, jiffies + 3 * HZ);
+ }
+
+ /* send read confirm */
+ outb(MG_CMD_RD_CONF, (unsigned long)host->dev_base + MG_REG_COMMAND);
+
+ /* goto next request */
+ if (!i)
+ mg_request(host->breq);
+}
+
+static void mg_write_intr(struct mg_host *host)
+{
+ u32 i, j;
+ u16 *buff;
+ struct request *req;
+
+ /* get current segment of request */
+ req = elv_next_request(host->breq);
+
+ /* check status */
+ do {
+ i = inb((unsigned long)host->dev_base + MG_REG_STATUS);
+ if (i & MG_REG_STATUS_BIT_BUSY)
+ break;
+ if (!MG_READY_OK(i))
+ break;
+ if ((req->nr_sectors <= 1) || (i & MG_REG_STATUS_BIT_DATA_REQ))
+ 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:
+ /* manipulate request */
+ req->sector++;
+ i = --req->nr_sectors;
+ --req->current_nr_sectors;
+ req->buffer += MG_SECTOR_SIZE;
+
+ /* let know if current segment or all done */
+ if (!i || (req->bio && req->current_nr_sectors <= 0))
+ end_request(req, 1);
+
+ /* write 1 sector and set handler if remains */
+ if (i > 0) {
+ buff = (u16 *)req->buffer;
+ for (j = 0; j < MG_STORAGE_BUFFER_SIZE >> 1; j++) {
+ outw(*buff, (unsigned long)host->dev_base +
+ MG_BUFF_OFFSET + (j << 1));
+ buff++;
+ }
+ MG_DBG("sector %ld, remaining=%ld, buffer=0x%p\n",
+ req->sector, req->nr_sectors, req->buffer);
+ 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 (!i)
+ mg_request(host->breq);
+}
+
+void mg_times_out(unsigned long data)
+{
+ struct mg_host *host = (struct mg_host *)data;
+ char *name;
+ struct request *req;
+
+ req = elv_next_request(host->breq);
+ if (!req)
+ return;
+
+ host->mg_do_intr = NULL;
+
+ name = req->rq_disk->disk_name;
+ printk(KERN_DEBUG "%s: timeout\n", name);
+
+ host->error = MG_ERR_TIMEOUT;
+ mg_bad_rw_intr(host);
+
+ mg_request(host->breq);
+}
+
+static void mg_request_poll(struct request_queue *q)
+{
+ struct request *req;
+ struct mg_host *host;
+
+ while ((req = elv_next_request(q)) != NULL) {
+ host = req->rq_disk->private_data;
+ if (blk_fs_request(req)) {
+ switch (rq_data_dir(req)) {
+ case READ:
+ mg_read(req);
+ break;
+ case WRITE:
+ mg_write(req);
+ break;
+ default:
+ printk(KERN_WARNING "%s:%d unknown command\n",
+ __func__, __LINE__);
+ end_request(req, 0);
+ break;
+ }
+ }
+ }
+}
+
+static unsigned int mg_issue_req(struct request *req,
+ struct mg_host *host,
+ unsigned int sect_num,
+ unsigned int sect_cnt)
+{
+ u16 *buff;
+ u32 i;
+
+ 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(MG_REG_CTRL_INTR_DISABLE,
+ (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, MG_REG_STATUS_BIT_DATA_REQ, MG_TMAX_WAIT_WR_DRQ);
+ outb(MG_REG_CTRL_INTR_ENABLE, (unsigned long)host->dev_base +
+ MG_REG_DRV_CTRL);
+ if (host->error) {
+ mg_bad_rw_intr(host);
+ return host->error;
+ }
+ buff = (u16 *)req->buffer;
+ for (i = 0; i < MG_SECTOR_SIZE >> 1; i++) {
+ outw(*buff, (unsigned long)host->dev_base +
+ MG_BUFF_OFFSET + (i << 1));
+ buff++;
+ }
+ mod_timer(&host->timer, jiffies + 3 * HZ);
+ outb(MG_CMD_WR_CONF, (unsigned long)host->dev_base +
+ MG_REG_COMMAND);
+ break;
+ default:
+ printk(KERN_WARNING "%s:%d unknown command\n",
+ __func__, __LINE__);
+ end_request(req, 0);
+ break;
+ }
+ return MG_ERR_NONE;
+}
+
+/* This function also called from IRQ context */
+static void mg_request(struct request_queue *q)
+{
+ struct request *req;
+ struct mg_host *host;
+ u32 sect_num, sect_cnt;
+
+ while (1) {
+ req = elv_next_request(q);
+ if (!req)
+ return;
+
+ host = req->rq_disk->private_data;
+
+ /* check unwanted request call */
+ if (host->mg_do_intr)
+ return;
+
+ del_timer(&host->timer);
+
+ sect_num = req->sector;
+ /* deal whole segments */
+ sect_cnt = req->nr_sectors;
+
+ /* 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);
+ end_request(req, 0);
+ continue;
+ }
+
+ if (!blk_fs_request(req))
+ return;
+
+ 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 struct block_device_operations mg_disk_ops = {
+ .getgeo = mg_getgeo
+};
+
+static int mg_suspend(struct platform_device *plat_dev, pm_message_t state)
+{
+ struct mg_drv_data *prv_data = plat_dev->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(MG_REG_CTRL_INTR_DISABLE,
+ (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(MG_REG_CTRL_INTR_ENABLE,
+ (unsigned long)host->dev_base +
+ MG_REG_DRV_CTRL);
+ return -EIO;
+ }
+
+ return 0;
+}
+
+static int mg_resume(struct platform_device *plat_dev)
+{
+ struct mg_drv_data *prv_data = plat_dev->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(MG_REG_CTRL_INTR_ENABLE, (unsigned long)host->dev_base +
+ MG_REG_DRV_CTRL);
+
+ return 0;
+}
+
+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 , rsc->end + 1);
+ 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))
+ 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 finised, 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_DISABLED | 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;
+ }
+
+ /* mflash is random device, thanx for the noop */
+ elevator_exit(host->breq->elevator);
+ err = elevator_init(host->breq, "noop");
+ if (err) {
+ printk(KERN_ERR "%s:%d (elevator_init) fail\n",
+ __func__, __LINE__);
+ goto probe_err_6;
+ }
+ blk_queue_max_sectors(host->breq, MG_MAX_SECTS);
+ blk_queue_hardsect_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,
+ .suspend = mg_suspend,
+ .resume = mg_resume,
+ .driver = {
+ .name = MG_DEV_NAME,
+ .owner = THIS_MODULE,
+ }
+};
+
+/****************************************************************************
+ *
+ * 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");
diff --git a/include/linux/mg_disk.h b/include/linux/mg_disk.h
new file mode 100644
index 0000000..1f76b1e
--- /dev/null
+++ b/include/linux/mg_disk.h
@@ -0,0 +1,206 @@
+/*
+ * include/linux/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.
+ */
+
+#ifndef __MG_DISK_H__
+#define __MG_DISK_H__
+
+#include <linux/blkdev.h>
+#include <linux/ata.h>
+
+/* name for block device */
+#define MG_DISK_NAME "mgd"
+/* name for platform device */
+#define MG_DEV_NAME "mg_disk"
+
+#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_STORAGE_BUFFER_SIZE 0x200
+#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)
+
+/* "Drive Select/Head Register" bit values */
+#define MG_REG_HEAD_MUST_BE_ON 0xA0 /* These 2 bits are always on */
+#define MG_REG_HEAD_DRIVE_MASTER (0x00 | MG_REG_HEAD_MUST_BE_ON)
+#define MG_REG_HEAD_DRIVE_SLAVE (0x10 | MG_REG_HEAD_MUST_BE_ON)
+#define MG_REG_HEAD_LBA_MODE (0x40 | MG_REG_HEAD_MUST_BE_ON)
+
+
+/* "Device Control Register" bit values */
+#define MG_REG_CTRL_INTR_ENABLE 0x0
+#define MG_REG_CTRL_INTR_DISABLE (0x1<<1)
+#define MG_REG_CTRL_RESET (0x1<<2)
+#define MG_REG_CTRL_INTR_POLA_ACTIVE_HIGH 0x0
+#define MG_REG_CTRL_INTR_POLA_ACTIVE_LOW (0x1<<4)
+#define MG_REG_CTRL_DPD_POLA_ACTIVE_LOW 0x0
+#define MG_REG_CTRL_DPD_POLA_ACTIVE_HIGH (0x1<<5)
+#define MG_REG_CTRL_DPD_DISABLE 0x0
+#define MG_REG_CTRL_DPD_ENABLE (0x1<<6)
+
+/* Status register bit */
+/* error bit in status register */
+#define MG_REG_STATUS_BIT_ERROR 0x01
+/* corrected error in status register */
+#define MG_REG_STATUS_BIT_CORRECTED_ERROR 0x04
+/* data request bit in status register */
+#define MG_REG_STATUS_BIT_DATA_REQ 0x08
+/* DSC - Drive Seek Complete */
+#define MG_REG_STATUS_BIT_SEEK_DONE 0x10
+/* DWF - Drive Write Fault */
+#define MG_REG_STATUS_BIT_WRITE_FAULT 0x20
+#define MG_REG_STATUS_BIT_READY 0x40
+#define MG_REG_STATUS_BIT_BUSY 0x80
+
+/* handy status */
+#define MG_STAT_READY (MG_REG_STATUS_BIT_READY | MG_REG_STATUS_BIT_SEEK_DONE)
+#define MG_READY_OK(s) (((s) & (MG_STAT_READY | \
+ (MG_REG_STATUS_BIT_BUSY | \
+ MG_REG_STATUS_BIT_WRITE_FAULT | \
+ MG_REG_STATUS_BIT_ERROR))) == MG_STAT_READY)
+
+/* Error register */
+#define MG_REG_ERR_AMNF 0x01
+#define MG_REG_ERR_ABRT 0x04
+#define MG_REG_ERR_IDNF 0x10
+#define MG_REG_ERR_UNC 0x40
+#define MG_REG_ERR_BBK 0x80
+
+/* 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
+
+/* device attribution */
+/* use mflash as boot device */
+#define MG_BOOT_DEV (1 << 0)
+/* use mflash as storage device */
+#define MG_STORAGE_DEV (1 << 1)
+/* same as MG_STORAGE_DEV, but bootloader already done reset sequence */
+#define MG_STORAGE_DEV_SKIP_RST (1 << 2)
+
+#define MG_DEV_MASK (MG_BOOT_DEV | MG_STORAGE_DEV | MG_STORAGE_DEV_SKIP_RST)
+
+/* names of GPIO resource */
+#define MG_RST_PIN "mg_rst"
+/* except MG_BOOT_DEV, reset-out pin should be assigned */
+#define MG_RSTOUT_PIN "mg_rstout"
+
+/* private driver data */
+struct mg_drv_data {
+ /* disk resource */
+ u32 use_polling;
+
+ /* device attribution */
+ u32 dev_attr;
+
+ /* internally used */
+ struct mg_host *host;
+};
+
+/* main structure for mflash driver */
+struct mg_host {
+ struct device *dev;
+
+ struct request_queue *breq;
+ 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 */
+
+#endif