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path: root/drivers/ide/tx4939ide.c
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/*
 * TX4939 internal IDE driver
 * Based on RBTX49xx patch from CELF patch archive.
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * (C) Copyright TOSHIBA CORPORATION 2005-2007
 */

#include <linux/module.h>
#include <linux/types.h>
#include <linux/ide.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/io.h>
#include <linux/scatterlist.h>

#include <asm/ide.h>

#define MODNAME	"tx4939ide"

/* ATA Shadow Registers (8-bit except for Data which is 16-bit) */
#define TX4939IDE_Data			0x000
#define TX4939IDE_Error_Feature		0x001
#define TX4939IDE_Sec			0x002
#define TX4939IDE_LBA0			0x003
#define TX4939IDE_LBA1			0x004
#define TX4939IDE_LBA2			0x005
#define TX4939IDE_DevHead		0x006
#define TX4939IDE_Stat_Cmd		0x007
#define TX4939IDE_AltStat_DevCtl	0x402
/* H/W DMA Registers  */
#define TX4939IDE_DMA_Cmd	0x800	/* 8-bit */
#define TX4939IDE_DMA_Stat	0x802	/* 8-bit */
#define TX4939IDE_PRD_Ptr	0x804	/* 32-bit */
/* ATA100 CORE Registers (16-bit) */
#define TX4939IDE_Sys_Ctl	0xc00
#define TX4939IDE_Xfer_Cnt_1	0xc08
#define TX4939IDE_Xfer_Cnt_2	0xc0a
#define TX4939IDE_Sec_Cnt	0xc10
#define TX4939IDE_Start_Lo_Addr	0xc18
#define TX4939IDE_Start_Up_Addr	0xc20
#define TX4939IDE_Add_Ctl	0xc28
#define TX4939IDE_Lo_Burst_Cnt	0xc30
#define TX4939IDE_Up_Burst_Cnt	0xc38
#define TX4939IDE_PIO_Addr	0xc88
#define TX4939IDE_H_Rst_Tim	0xc90
#define TX4939IDE_Int_Ctl	0xc98
#define TX4939IDE_Pkt_Cmd	0xcb8
#define TX4939IDE_Bxfer_Cnt_Hi	0xcc0
#define TX4939IDE_Bxfer_Cnt_Lo	0xcc8
#define TX4939IDE_Dev_TErr	0xcd0
#define TX4939IDE_Pkt_Xfer_Ctl	0xcd8
#define TX4939IDE_Start_TAddr	0xce0

/* bits for Int_Ctl */
#define TX4939IDE_INT_ADDRERR	0x80
#define TX4939IDE_INT_REACHMUL	0x40
#define TX4939IDE_INT_DEVTIMING	0x20
#define TX4939IDE_INT_UDMATERM	0x10
#define TX4939IDE_INT_TIMER	0x08
#define TX4939IDE_INT_BUSERR	0x04
#define TX4939IDE_INT_XFEREND	0x02
#define TX4939IDE_INT_HOST	0x01

#define TX4939IDE_IGNORE_INTS	\
	(TX4939IDE_INT_ADDRERR | TX4939IDE_INT_REACHMUL | \
	 TX4939IDE_INT_DEVTIMING | TX4939IDE_INT_UDMATERM | \
	 TX4939IDE_INT_TIMER | TX4939IDE_INT_XFEREND)

#ifdef __BIG_ENDIAN
#define tx4939ide_swizzlel(a)	((a) ^ 4)
#define tx4939ide_swizzlew(a)	((a) ^ 6)
#define tx4939ide_swizzleb(a)	((a) ^ 7)
#else
#define tx4939ide_swizzlel(a)	(a)
#define tx4939ide_swizzlew(a)	(a)
#define tx4939ide_swizzleb(a)	(a)
#endif

static u16 tx4939ide_readw(void __iomem *base, u32 reg)
{
	return __raw_readw(base + tx4939ide_swizzlew(reg));
}
static u8 tx4939ide_readb(void __iomem *base, u32 reg)
{
	return __raw_readb(base + tx4939ide_swizzleb(reg));
}
static void tx4939ide_writel(u32 val, void __iomem *base, u32 reg)
{
	__raw_writel(val, base + tx4939ide_swizzlel(reg));
}
static void tx4939ide_writew(u16 val, void __iomem *base, u32 reg)
{
	__raw_writew(val, base + tx4939ide_swizzlew(reg));
}
static void tx4939ide_writeb(u8 val, void __iomem *base, u32 reg)
{
	__raw_writeb(val, base + tx4939ide_swizzleb(reg));
}

#define TX4939IDE_BASE(hwif)	((void __iomem *)(hwif)->extra_base)

static void tx4939ide_set_pio_mode(ide_drive_t *drive, const u8 pio)
{
	ide_hwif_t *hwif = drive->hwif;
	int is_slave = drive->dn;
	u32 mask, val;
	u8 safe = pio;
	ide_drive_t *pair;

	pair = ide_get_pair_dev(drive);
	if (pair)
		safe = min(safe, ide_get_best_pio_mode(pair, 255, 4));
	/*
	 * Update Command Transfer Mode for master/slave and Data
	 * Transfer Mode for this drive.
	 */
	mask = is_slave ? 0x07f00000 : 0x000007f0;
	val = ((safe << 8) | (pio << 4)) << (is_slave ? 16 : 0);
	hwif->select_data = (hwif->select_data & ~mask) | val;
	/* tx4939ide_tf_load_fixup() will set the Sys_Ctl register */
}

static void tx4939ide_set_dma_mode(ide_drive_t *drive, const u8 mode)
{
	ide_hwif_t *hwif = drive->hwif;
	u32 mask, val;

	/* Update Data Transfer Mode for this drive. */
	if (mode >= XFER_UDMA_0)
		val = mode - XFER_UDMA_0 + 8;
	else
		val = mode - XFER_MW_DMA_0 + 5;
	if (drive->dn) {
		mask = 0x00f00000;
		val <<= 20;
	} else {
		mask = 0x000000f0;
		val <<= 4;
	}
	hwif->select_data = (hwif->select_data & ~mask) | val;
	/* tx4939ide_tf_load_fixup() will set the Sys_Ctl register */
}

static u16 tx4939ide_check_error_ints(ide_hwif_t *hwif)
{
	void __iomem *base = TX4939IDE_BASE(hwif);
	u16 ctl = tx4939ide_readw(base, TX4939IDE_Int_Ctl);

	if (ctl & TX4939IDE_INT_BUSERR) {
		/* reset FIFO */
		u16 sysctl = tx4939ide_readw(base, TX4939IDE_Sys_Ctl);

		tx4939ide_writew(sysctl | 0x4000, base, TX4939IDE_Sys_Ctl);
		mmiowb();
		/* wait 12GBUSCLK (typ. 60ns @ GBUS200MHz, max 270ns) */
		ndelay(270);
		tx4939ide_writew(sysctl, base, TX4939IDE_Sys_Ctl);
	}
	if (ctl & (TX4939IDE_INT_ADDRERR |
		   TX4939IDE_INT_DEVTIMING | TX4939IDE_INT_BUSERR))
		pr_err("%s: Error interrupt %#x (%s%s%s )\n",
		       hwif->name, ctl,
		       ctl & TX4939IDE_INT_ADDRERR ? " Address-Error" : "",
		       ctl & TX4939IDE_INT_DEVTIMING ? " DEV-Timing" : "",
		       ctl & TX4939IDE_INT_BUSERR ? " Bus-Error" : "");
	return ctl;
}

static void tx4939ide_clear_irq(ide_drive_t *drive)
{
	ide_hwif_t *hwif;
	void __iomem *base;
	u16 ctl;

	/*
	 * tx4939ide_dma_test_irq() and tx4939ide_dma_end() do all job
	 * for DMA case.
	 */
	if (drive->waiting_for_dma)
		return;
	hwif = drive->hwif;
	base = TX4939IDE_BASE(hwif);
	ctl = tx4939ide_check_error_ints(hwif);
	tx4939ide_writew(ctl, base, TX4939IDE_Int_Ctl);
}

static u8 tx4939ide_cable_detect(ide_hwif_t *hwif)
{
	void __iomem *base = TX4939IDE_BASE(hwif);

	return tx4939ide_readw(base, TX4939IDE_Sys_Ctl) & 0x2000 ?
		ATA_CBL_PATA40 : ATA_CBL_PATA80;
}

#ifdef __BIG_ENDIAN
static void tx4939ide_dma_host_set(ide_drive_t *drive, int on)
{
	ide_hwif_t *hwif = drive->hwif;
	u8 unit = drive->dn;
	void __iomem *base = TX4939IDE_BASE(hwif);
	u8 dma_stat = tx4939ide_readb(base, TX4939IDE_DMA_Stat);

	if (on)
		dma_stat |= (1 << (5 + unit));
	else
		dma_stat &= ~(1 << (5 + unit));

	tx4939ide_writeb(dma_stat, base, TX4939IDE_DMA_Stat);
}
#else
#define tx4939ide_dma_host_set	ide_dma_host_set
#endif

static u8 tx4939ide_clear_dma_status(void __iomem *base)
{
	u8 dma_stat;

	/* read DMA status for INTR & ERROR flags */
	dma_stat = tx4939ide_readb(base, TX4939IDE_DMA_Stat);
	/* clear INTR & ERROR flags */
	tx4939ide_writeb(dma_stat | ATA_DMA_INTR | ATA_DMA_ERR, base,
			 TX4939IDE_DMA_Stat);
	/* recover intmask cleared by writing to bit2 of DMA_Stat */
	tx4939ide_writew(TX4939IDE_IGNORE_INTS << 8, base, TX4939IDE_Int_Ctl);
	return dma_stat;
}

#ifdef __BIG_ENDIAN
/* custom ide_build_dmatable to handle swapped layout */
static int tx4939ide_build_dmatable(ide_drive_t *drive, struct ide_cmd *cmd)
{
	ide_hwif_t *hwif = drive->hwif;
	u32 *table = (u32 *)hwif->dmatable_cpu;
	unsigned int count = 0;
	int i;
	struct scatterlist *sg;

	for_each_sg(hwif->sg_table, sg, cmd->sg_nents, i) {
		u32 cur_addr, cur_len, bcount;

		cur_addr = sg_dma_address(sg);
		cur_len = sg_dma_len(sg);

		/*
		 * Fill in the DMA table, without crossing any 64kB boundaries.
		 */

		while (cur_len) {
			if (count++ >= PRD_ENTRIES)
				goto use_pio_instead;

			bcount = 0x10000 - (cur_addr & 0xffff);
			if (bcount > cur_len)
				bcount = cur_len;
			/*
			 * This workaround for zero count seems required.
			 * (standard ide_build_dmatable does it too)
			 */
			if (bcount == 0x10000)
				bcount = 0x8000;
			*table++ = bcount & 0xffff;
			*table++ = cur_addr;
			cur_addr += bcount;
			cur_len -= bcount;
		}
	}

	if (count) {
		*(table - 2) |= 0x80000000;
		return count;
	}

use_pio_instead:
	printk(KERN_ERR "%s: %s\n", drive->name,
		count ? "DMA table too small" : "empty DMA table?");

	return 0; /* revert to PIO for this request */
}
#else
#define tx4939ide_build_dmatable	ide_build_dmatable
#endif

static int tx4939ide_dma_setup(ide_drive_t *drive, struct ide_cmd *cmd)
{
	ide_hwif_t *hwif = drive->hwif;
	void __iomem *base = TX4939IDE_BASE(hwif);
	u8 rw = (cmd->tf_flags & IDE_TFLAG_WRITE) ? 0 : ATA_DMA_WR;

	/* fall back to PIO! */
	if (tx4939ide_build_dmatable(drive, cmd) == 0)
		return 1;

	/* PRD table */
	tx4939ide_writel(hwif->dmatable_dma, base, TX4939IDE_PRD_Ptr);

	/* specify r/w */
	tx4939ide_writeb(rw, base, TX4939IDE_DMA_Cmd);

	/* clear INTR & ERROR flags */
	tx4939ide_clear_dma_status(base);

	tx4939ide_writew(SECTOR_SIZE / 2, base, drive->dn ?
			 TX4939IDE_Xfer_Cnt_2 : TX4939IDE_Xfer_Cnt_1);

	tx4939ide_writew(cmd->rq->nr_sectors, base, TX4939IDE_Sec_Cnt);

	return 0;
}

static int tx4939ide_dma_end(ide_drive_t *drive)
{
	ide_hwif_t *hwif = drive->hwif;
	u8 dma_stat, dma_cmd;
	void __iomem *base = TX4939IDE_BASE(hwif);
	u16 ctl = tx4939ide_readw(base, TX4939IDE_Int_Ctl);

	/* get DMA command mode */
	dma_cmd = tx4939ide_readb(base, TX4939IDE_DMA_Cmd);
	/* stop DMA */
	tx4939ide_writeb(dma_cmd & ~ATA_DMA_START, base, TX4939IDE_DMA_Cmd);

	/* read and clear the INTR & ERROR bits */
	dma_stat = tx4939ide_clear_dma_status(base);

#define CHECK_DMA_MASK (ATA_DMA_ACTIVE | ATA_DMA_ERR | ATA_DMA_INTR)

	/* verify good DMA status */
	if ((dma_stat & CHECK_DMA_MASK) == 0 &&
	    (ctl & (TX4939IDE_INT_XFEREND | TX4939IDE_INT_HOST)) ==
	    (TX4939IDE_INT_XFEREND | TX4939IDE_INT_HOST))
		/* INT_IDE lost... bug? */
		return 0;
	return ((dma_stat & CHECK_DMA_MASK) !=
		ATA_DMA_INTR) ? 0x10 | dma_stat : 0;
}

/* returns 1 if DMA IRQ issued, 0 otherwise */
static int tx4939ide_dma_test_irq(ide_drive_t *drive)
{
	ide_hwif_t *hwif = drive->hwif;
	void __iomem *base = TX4939IDE_BASE(hwif);
	u16 ctl, ide_int;
	u8 dma_stat, stat;
	int found = 0;

	ctl = tx4939ide_check_error_ints(hwif);
	ide_int = ctl & (TX4939IDE_INT_XFEREND | TX4939IDE_INT_HOST);
	switch (ide_int) {
	case TX4939IDE_INT_HOST:
		/* On error, XFEREND might not be asserted. */
		stat = tx4939ide_readb(base, TX4939IDE_AltStat_DevCtl);
		if ((stat & (ATA_BUSY | ATA_DRQ | ATA_ERR)) == ATA_ERR)
			found = 1;
		else
			/* Wait for XFEREND (Mask HOST and unmask XFEREND) */
			ctl &= ~TX4939IDE_INT_XFEREND << 8;
		ctl |= ide_int << 8;
		break;
	case TX4939IDE_INT_HOST | TX4939IDE_INT_XFEREND:
		dma_stat = tx4939ide_readb(base, TX4939IDE_DMA_Stat);
		if (!(dma_stat & ATA_DMA_INTR))
			pr_warning("%s: weird interrupt status. "
				   "DMA_Stat %#02x int_ctl %#04x\n",
				   hwif->name, dma_stat, ctl);
		found = 1;
		break;
	}
	/*
	 * Do not clear XFEREND, HOST now.  They will be cleared by
	 * clearing bit2 of DMA_Stat.
	 */
	ctl &= ~ide_int;
	tx4939ide_writew(ctl, base, TX4939IDE_Int_Ctl);
	return found;
}

#ifdef __BIG_ENDIAN
static u8 tx4939ide_dma_sff_read_status(ide_hwif_t *hwif)
{
	void __iomem *base = TX4939IDE_BASE(hwif);

	return tx4939ide_readb(base, TX4939IDE_DMA_Stat);
}
#else
#define tx4939ide_dma_sff_read_status ide_dma_sff_read_status
#endif

static void tx4939ide_init_hwif(ide_hwif_t *hwif)
{
	void __iomem *base = TX4939IDE_BASE(hwif);

	/* Soft Reset */
	tx4939ide_writew(0x8000, base, TX4939IDE_Sys_Ctl);
	mmiowb();
	/* at least 20 GBUSCLK (typ. 100ns @ GBUS200MHz, max 450ns) */
	ndelay(450);
	tx4939ide_writew(0x0000, base, TX4939IDE_Sys_Ctl);
	/* mask some interrupts and clear all interrupts */
	tx4939ide_writew((TX4939IDE_IGNORE_INTS << 8) | 0xff, base,
			 TX4939IDE_Int_Ctl);

	tx4939ide_writew(0x0008, base, TX4939IDE_Lo_Burst_Cnt);
	tx4939ide_writew(0, base, TX4939IDE_Up_Burst_Cnt);
}

static int tx4939ide_init_dma(ide_hwif_t *hwif, const struct ide_port_info *d)
{
	hwif->dma_base =
		hwif->extra_base + tx4939ide_swizzleb(TX4939IDE_DMA_Cmd);
	/*
	 * Note that we cannot use ATA_DMA_TABLE_OFS, ATA_DMA_STATUS
	 * for big endian.
	 */
	return ide_allocate_dma_engine(hwif);
}

static void tx4939ide_tf_load_fixup(ide_drive_t *drive)
{
	ide_hwif_t *hwif = drive->hwif;
	void __iomem *base = TX4939IDE_BASE(hwif);
	u16 sysctl = hwif->select_data >> (drive->dn ? 16 : 0);

	/*
	 * Fix ATA100 CORE System Control Register. (The write to the
	 * Device/Head register may write wrong data to the System
	 * Control Register)
	 * While Sys_Ctl is written here, dev_select() is not needed.
	 */
	tx4939ide_writew(sysctl, base, TX4939IDE_Sys_Ctl);
}

static void tx4939ide_tf_load(ide_drive_t *drive, struct ide_cmd *cmd)
{
	ide_tf_load(drive, cmd);

	if (cmd->tf_flags & IDE_TFLAG_OUT_DEVICE)
		tx4939ide_tf_load_fixup(drive);
}

#ifdef __BIG_ENDIAN

/* custom iops (independent from SWAP_IO_SPACE) */
static void tx4939ide_input_data_swap(ide_drive_t *drive, struct ide_cmd *cmd,
				void *buf, unsigned int len)
{
	unsigned long port = drive->hwif->io_ports.data_addr;
	unsigned short *ptr = buf;
	unsigned int count = (len + 1) / 2;

	while (count--)
		*ptr++ = cpu_to_le16(__raw_readw((void __iomem *)port));
	__ide_flush_dcache_range((unsigned long)buf, roundup(len, 2));
}

static void tx4939ide_output_data_swap(ide_drive_t *drive, struct ide_cmd *cmd,
				void *buf, unsigned int len)
{
	unsigned long port = drive->hwif->io_ports.data_addr;
	unsigned short *ptr = buf;
	unsigned int count = (len + 1) / 2;

	while (count--) {
		__raw_writew(le16_to_cpu(*ptr), (void __iomem *)port);
		ptr++;
	}
	__ide_flush_dcache_range((unsigned long)buf, roundup(len, 2));
}

static const struct ide_tp_ops tx4939ide_tp_ops = {
	.exec_command		= ide_exec_command,
	.read_status		= ide_read_status,
	.read_altstatus		= ide_read_altstatus,
	.write_devctl		= ide_write_devctl,

	.dev_select		= ide_dev_select,
	.tf_load		= tx4939ide_tf_load,
	.tf_read		= ide_tf_read,

	.input_data		= tx4939ide_input_data_swap,
	.output_data		= tx4939ide_output_data_swap,
};

#else	/* __LITTLE_ENDIAN */

static const struct ide_tp_ops tx4939ide_tp_ops = {
	.exec_command		= ide_exec_command,
	.read_status		= ide_read_status,
	.read_altstatus		= ide_read_altstatus,
	.write_devctl		= ide_write_devctl,

	.dev_select		= ide_dev_select,
	.tf_load		= tx4939ide_tf_load,
	.tf_read		= ide_tf_read,

	.input_data		= ide_input_data,
	.output_data		= ide_output_data,
};

#endif	/* __LITTLE_ENDIAN */

static const struct ide_port_ops tx4939ide_port_ops = {
	.set_pio_mode		= tx4939ide_set_pio_mode,
	.set_dma_mode		= tx4939ide_set_dma_mode,
	.clear_irq		= tx4939ide_clear_irq,
	.cable_detect		= tx4939ide_cable_detect,
};

static const struct ide_dma_ops tx4939ide_dma_ops = {
	.dma_host_set		= tx4939ide_dma_host_set,
	.dma_setup		= tx4939ide_dma_setup,
	.dma_start		= ide_dma_start,
	.dma_end		= tx4939ide_dma_end,
	.dma_test_irq		= tx4939ide_dma_test_irq,
	.dma_lost_irq		= ide_dma_lost_irq,
	.dma_timer_expiry	= ide_dma_sff_timer_expiry,
	.dma_sff_read_status	= tx4939ide_dma_sff_read_status,
};

static const struct ide_port_info tx4939ide_port_info __initdata = {
	.init_hwif		= tx4939ide_init_hwif,
	.init_dma		= tx4939ide_init_dma,
	.port_ops		= &tx4939ide_port_ops,
	.dma_ops		= &tx4939ide_dma_ops,
	.tp_ops			= &tx4939ide_tp_ops,
	.host_flags		= IDE_HFLAG_MMIO,
	.pio_mask		= ATA_PIO4,
	.mwdma_mask		= ATA_MWDMA2,
	.udma_mask		= ATA_UDMA5,
	.chipset		= ide_generic,
};

static int __init tx4939ide_probe(struct platform_device *pdev)
{
	hw_regs_t hw;
	hw_regs_t *hws[] = { &hw, NULL, NULL, NULL };
	struct ide_host *host;
	struct resource *res;
	int irq, ret;
	unsigned long mapbase;

	irq = platform_get_irq(pdev, 0);
	if (irq < 0)
		return -ENODEV;
	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!res)
		return -ENODEV;

	if (!devm_request_mem_region(&pdev->dev, res->start,
				     res->end - res->start + 1, "tx4938ide"))
		return -EBUSY;
	mapbase = (unsigned long)devm_ioremap(&pdev->dev, res->start,
					      res->end - res->start + 1);
	if (!mapbase)
		return -EBUSY;
	memset(&hw, 0, sizeof(hw));
	hw.io_ports.data_addr =
		mapbase + tx4939ide_swizzlew(TX4939IDE_Data);
	hw.io_ports.error_addr =
		mapbase + tx4939ide_swizzleb(TX4939IDE_Error_Feature);
	hw.io_ports.nsect_addr =
		mapbase + tx4939ide_swizzleb(TX4939IDE_Sec);
	hw.io_ports.lbal_addr =
		mapbase + tx4939ide_swizzleb(TX4939IDE_LBA0);
	hw.io_ports.lbam_addr =
		mapbase + tx4939ide_swizzleb(TX4939IDE_LBA1);
	hw.io_ports.lbah_addr =
		mapbase + tx4939ide_swizzleb(TX4939IDE_LBA2);
	hw.io_ports.device_addr =
		mapbase + tx4939ide_swizzleb(TX4939IDE_DevHead);
	hw.io_ports.command_addr =
		mapbase + tx4939ide_swizzleb(TX4939IDE_Stat_Cmd);
	hw.io_ports.ctl_addr =
		mapbase + tx4939ide_swizzleb(TX4939IDE_AltStat_DevCtl);
	hw.irq = irq;
	hw.dev = &pdev->dev;

	pr_info("TX4939 IDE interface (base %#lx, irq %d)\n", mapbase, irq);
	host = ide_host_alloc(&tx4939ide_port_info, hws);
	if (!host)
		return -ENOMEM;
	/* use extra_base for base address of the all registers */
	host->ports[0]->extra_base = mapbase;
	ret = ide_host_register(host, &tx4939ide_port_info, hws);
	if (ret) {
		ide_host_free(host);
		return ret;
	}
	platform_set_drvdata(pdev, host);
	return 0;
}

static int __exit tx4939ide_remove(struct platform_device *pdev)
{
	struct ide_host *host = platform_get_drvdata(pdev);

	ide_host_remove(host);
	return 0;
}

#ifdef CONFIG_PM
static int tx4939ide_resume(struct platform_device *dev)
{
	struct ide_host *host = platform_get_drvdata(dev);
	ide_hwif_t *hwif = host->ports[0];

	tx4939ide_init_hwif(hwif);
	return 0;
}
#else
#define tx4939ide_resume	NULL
#endif

static struct platform_driver tx4939ide_driver = {
	.driver = {
		.name = MODNAME,
		.owner = THIS_MODULE,
	},
	.remove = __exit_p(tx4939ide_remove),
	.resume = tx4939ide_resume,
};

static int __init tx4939ide_init(void)
{
	return platform_driver_probe(&tx4939ide_driver, tx4939ide_probe);
}

static void __exit tx4939ide_exit(void)
{
	platform_driver_unregister(&tx4939ide_driver);
}

module_init(tx4939ide_init);
module_exit(tx4939ide_exit);

MODULE_DESCRIPTION("TX4939 internal IDE driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:tx4939ide");