Re: [PATCH 4/4] pata_samsung: Add Samsung PATA controller driver

[Ben Dooks <ben-linux@fluff.org>]

On Thu, May 27, 2010 at 05:22:04PM +0900, Kukjin Kim wrote:
> From: Abhilash Kesavan <a.kesavan@samsung.com>
> 
> Adds support for the Samsung PATA controller. This driver is based on the
> Libata subsystem and references the earlier patches sent for IDE subsystem.
> 
> Signed-off-by: Abhilash Kesavan <a.kesavan@samsung.com>
> Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
> ---
>  drivers/ata/Kconfig        |    9 +
>  drivers/ata/Makefile       |    1 +
>  drivers/ata/pata_samsung.c |  591 ++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 601 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/ata/pata_samsung.c
> 
> diff --git a/drivers/ata/Kconfig b/drivers/ata/Kconfig
> index e68541f..ce40f66 100644
> --- a/drivers/ata/Kconfig
> +++ b/drivers/ata/Kconfig
> @@ -640,6 +640,15 @@ config PATA_RZ1000
>  
>  	  If unsure, say N.
>  
> +config PATA_SAMSUNG
> +	tristate "Samsung SoC PATA support"
> +	depends on S3C_DEV_IDE
> +	help
> +	  This option enables basic support for Samsung's S3C/S5P board
> +	  PATA controllers via the new ATA layer
> +
> +	  If unsure, say N.
> +
>  config PATA_SC1200
>  	tristate "SC1200 PATA support"
>  	depends on PCI
> diff --git a/drivers/ata/Makefile b/drivers/ata/Makefile
> index d0a93c4..0b6d29a 100644
> --- a/drivers/ata/Makefile
> +++ b/drivers/ata/Makefile
> @@ -62,6 +62,7 @@ obj-$(CONFIG_PATA_RADISYS)	+= pata_radisys.o
>  obj-$(CONFIG_PATA_RB532)	+= pata_rb532_cf.o
>  obj-$(CONFIG_PATA_RDC)		+= pata_rdc.o
>  obj-$(CONFIG_PATA_RZ1000)	+= pata_rz1000.o
> +obj-$(CONFIG_PATA_SAMSUNG)	+= pata_samsung.o
do you want to call it pata_samsung_soc.o instead, in case samsung make
otehr types of pata controller?

>  obj-$(CONFIG_PATA_SC1200)	+= pata_sc1200.o
>  obj-$(CONFIG_PATA_SERVERWORKS)	+= pata_serverworks.o
>  obj-$(CONFIG_PATA_SIL680)	+= pata_sil680.o
> diff --git a/drivers/ata/pata_samsung.c b/drivers/ata/pata_samsung.c
> new file mode 100644
> index 0000000..14381e4
> --- /dev/null
> +++ b/drivers/ata/pata_samsung.c
> @@ -0,0 +1,591 @@
> +/* linux/drivers/ata/pata_samsung.c
> + *
> + * Copyright (c) 2010 Samsung Electronics Co., Ltd.
> + *		http://www.samsung.com
> + *
> + * PATA driver for Samsung SoC's.
SoCs.
> + * Supports CF Interface in True IDE mode. Currently only PIO mode has been
> + * implemented; UDMA support has to be added.
> + *
> + * Based on:
> + *	PATA driver for AT91SAM9260 Static Memory Controller
> + *	PATA driver for Toshiba SCC controller
> + *
> + * 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/init.h>
> +#include <linux/clk.h>
> +#include <linux/libata.h>
> +#include <linux/platform_device.h>
> +#include <linux/slab.h>
> +
> +#include <plat/ata.h>
> +#include <plat/regs-ata.h>
> +
> +#define DRV_NAME "pata_samsung"
> +#define DRV_VERSION "0.1"
> +
> +enum s3c_cpu_type {
> +	TYPE_S3C6400,
> +	TYPE_S5PC100,
> +	TYPE_S5PV210,
> +};
> +
> +/*
> + * struct s3c_ide_info - S3C PATA instance.
> + * @clk: The clock resource for this controller.
> + * @ide_addr: The area mapped for the hardware registers.
> + * @sfr_addr: The area mapped for the special function registers.
> + * @irq: The IRQ number we are using.
> + * @cpu_type: The exact type of this controller.
> + * @fifo_status_reg: The ATA_FIFO_STATUS register offset.
> + */
> +struct s3c_ide_info {
> +	struct clk *clk;
> +	void __iomem *ide_addr;
> +	void __iomem *sfr_addr;
> +	unsigned int irq;
> +	enum s3c_cpu_type cpu_type;
> +	unsigned int fifo_status_reg;
> +};
> +
> +static unsigned long piotime[5];
> +
> +static void pata_s3c_set_endian(void *s3c_ide_regbase, u8 mode)
> +{
> +	u32 reg = readl(s3c_ide_regbase + S3C_ATA_CFG);
> +	reg = mode ? (reg & ~S3C_ATA_CFG_SWAP) : (reg | S3C_ATA_CFG_SWAP);
> +	writel(reg, s3c_ide_regbase + S3C_ATA_CFG);
> +}
> +
> +static void pata_s3c_tune_chipset(struct s3c_ide_info *info, u8 ide_mode)
> +{
> +	ulong ata_cfg = readl(info->ide_addr + S3C_ATA_CFG);
> +
> +	/* IORDY is enabled for modes > PIO2 */
> +	if (XFER_PIO_0 <= ide_mode && ide_mode <= XFER_PIO_4) {
> +
> +		switch (ide_mode) {
> +		case XFER_PIO_0:
> +		case XFER_PIO_1:
> +		case XFER_PIO_2:
> +			ata_cfg &= (~S3C_ATA_CFG_IORDYEN);
> +			break;
> +		case XFER_PIO_3:
> +		case XFER_PIO_4:
> +			ata_cfg |= S3C_ATA_CFG_IORDYEN;
> +			break;
> +		}
> +
> +		writel(ata_cfg, info->ide_addr + S3C_ATA_CFG);
> +		writel(piotime[ide_mode - XFER_PIO_0],
> +			info->ide_addr + S3C_ATA_PIO_TIME);
> +	} else {
> +		/* Default to PIO0 */
> +		ata_cfg &= (~S3C_ATA_CFG_IORDYEN);
technically no need to ().
> +		writel(ata_cfg, info->ide_addr + S3C_ATA_CFG);
> +		writel(piotime[0], info->ide_addr + S3C_ATA_PIO_TIME);
> +	}
> +}
> +
> +static void
> +pata_s3c_set_piomode(struct ata_port *ap, struct ata_device *adev)
> +{
> +	struct s3c_ide_info *info = ap->host->private_data;
> +
> +	/* Configure IORDY based on PIO mode and also set the timing value */
> +	pata_s3c_tune_chipset(info, adev->pio_mode);
> +}
> +
> +/*
> + * Waits until the IDE controller is able to perform next read/write
> + * operation to the disk. Needed for 64XX series boards only.
> + */
> +static int wait_for_host_ready(struct s3c_ide_info *info)
> +{
> +	ulong timeout;
> +
> +	/* wait for maximum of 20 msec */
> +	timeout = jiffies + msecs_to_jiffies(20);
> +	while (time_before(jiffies, timeout)) {
> +		if ((readl(info->ide_addr + info->fifo_status_reg) >> 28) == 0)
> +			return 0;
> +	}
> +	return -EBUSY;
> +}
> +
> +/*
> + * Writes to one of the task file registers.
> + */
> +static void ata_outb(struct ata_host *host, u8 addr, void __iomem *reg)
> +{
> +	struct s3c_ide_info *info = host->private_data;
> +
> +	wait_for_host_ready(info);
> +	__raw_writeb(addr, reg);
> +}

probably want writeb() here. you've used the non __raw versions elsewhere.

> +/*
> + * Reads from one of the task file registers.
> + */
> +static u8 ata_inb(struct ata_host *host, void __iomem *reg)
> +{
> +	struct s3c_ide_info *info = host->private_data;
> +	u8 temp;
> +
> +	wait_for_host_ready(info);
> +	temp = __raw_readb(reg);
> +	wait_for_host_ready(info);
> +	temp = __raw_readb(info->ide_addr + S3C_ATA_PIO_RDATA);
> +	return temp;
> +}
> +
> +/*
> + * pata_s3c_tf_load - send taskfile registers to host controller
> + */
> +static void pata_s3c_tf_load(struct ata_port *ap,
> +				const struct ata_taskfile *tf)
> +{
> +	struct ata_ioports *ioaddr = &ap->ioaddr;
> +	unsigned int is_addr = tf->flags & ATA_TFLAG_ISADDR;
> +
> +	if (tf->ctl != ap->last_ctl) {
> +		if (ioaddr->ctl_addr)
> +			ata_outb(ap->host, tf->ctl, ioaddr->ctl_addr);
> +		ap->last_ctl = tf->ctl;
> +		ata_wait_idle(ap);
> +	}
> +
> +	if (is_addr && (tf->flags & ATA_TFLAG_LBA48)) {
> +		WARN_ON_ONCE(!ioaddr->ctl_addr);
> +		ata_outb(ap->host, tf->hob_feature, ioaddr->feature_addr);
> +		ata_outb(ap->host, tf->hob_nsect, ioaddr->nsect_addr);
> +		ata_outb(ap->host, tf->hob_lbal, ioaddr->lbal_addr);
> +		ata_outb(ap->host, tf->hob_lbam, ioaddr->lbam_addr);
> +		ata_outb(ap->host, tf->hob_lbah, ioaddr->lbah_addr);
> +	}
> +
> +	if (is_addr) {
> +		ata_outb(ap->host, tf->feature, ioaddr->feature_addr);
> +		ata_outb(ap->host, tf->nsect, ioaddr->nsect_addr);
> +		ata_outb(ap->host, tf->lbal, ioaddr->lbal_addr);
> +		ata_outb(ap->host, tf->lbam, ioaddr->lbam_addr);
> +		ata_outb(ap->host, tf->lbah, ioaddr->lbah_addr);
> +	}
> +
> +	if (tf->flags & ATA_TFLAG_DEVICE)
> +		ata_outb(ap->host, tf->device, ioaddr->device_addr);
> +
> +	ata_wait_idle(ap);
> +}
> +
> +/*
> + * pata_s3c_tf_read - input device's ATA taskfile shadow registers
> + */
> +static void pata_s3c_tf_read(struct ata_port *ap, struct ata_taskfile *tf)
> +{
> +	struct ata_ioports *ioaddr = &ap->ioaddr;
> +
> +	tf->command = ata_sff_check_status(ap);
> +	tf->feature = ata_inb(ap->host, ioaddr->error_addr);
> +	tf->nsect = ata_inb(ap->host, ioaddr->nsect_addr);
> +	tf->lbal = ata_inb(ap->host, ioaddr->lbal_addr);
> +	tf->lbam = ata_inb(ap->host, ioaddr->lbam_addr);
> +	tf->lbah = ata_inb(ap->host, ioaddr->lbah_addr);
> +	tf->device = ata_inb(ap->host, ioaddr->device_addr);
> +
> +	if (tf->flags & ATA_TFLAG_LBA48) {
> +		if (likely(ioaddr->ctl_addr)) {
> +			iowrite8(tf->ctl | ATA_HOB, ioaddr->ctl_addr);
> +			tf->hob_feature = ata_inb(ap->host, ioaddr->error_addr);
> +			tf->hob_nsect = ata_inb(ap->host, ioaddr->nsect_addr);
> +			tf->hob_lbal = ata_inb(ap->host, ioaddr->lbal_addr);
> +			tf->hob_lbam = ata_inb(ap->host, ioaddr->lbam_addr);
> +			tf->hob_lbah = ata_inb(ap->host, ioaddr->lbah_addr);
> +			iowrite8(tf->ctl, ioaddr->ctl_addr);
> +			ap->last_ctl = tf->ctl;
> +		} else
> +			WARN_ON_ONCE(1);
> +	}
> +}
> +
> +/*
> + * pata_s3c_exec_command - issue ATA command to host controller
> + */
> +static void pata_s3c_exec_command(struct ata_port *ap,
> +				const struct ata_taskfile *tf)
> +{
> +	ata_outb(ap->host, tf->command, ap->ioaddr.command_addr);
> +	ata_sff_pause(ap);
> +}
> +
> +/*
> + * pata_s3c_check_status - Read device status register
> + */
> +static u8 pata_s3c_check_status(struct ata_port *ap)
> +{
> +	return ata_inb(ap->host, ap->ioaddr.status_addr);
> +}
> +
> +/*
> + * pata_s3c_data_xfer - Transfer data by PIO
> + */
> +unsigned int pata_s3c_data_xfer(struct ata_device *dev, unsigned char *buf,
> +				unsigned int buflen, int rw)
> +{
> +	struct ata_port *ap = dev->link->ap;
> +	struct s3c_ide_info *info = ap->host->private_data;
> +	void __iomem *data_addr = ap->ioaddr.data_addr;
> +	unsigned int words = buflen >> 1, i;
> +	u16 *temp_addr = (u16 *)buf;

hmm, how about calling it data_ptr instead of temp_addr?

> +	if (rw == READ) {
> +		for (i = 0; i < words; i++, temp_addr++) {
> +			wait_for_host_ready(info);
> +			*temp_addr = __raw_readw(data_addr);
> +			wait_for_host_ready(info);
> +			*temp_addr = __raw_readw(info->ide_addr
> +					+ S3C_ATA_PIO_RDATA)

think you want readw() here, please ensure consitency.

this also look a bit weird, you are writing to *temp_addr twice,
could you simply dicscard the first read?

note, you say s3c64xx only needs wait_for_host_ready() but you
always call it?

> +		}
> +	} else {
> +		for (i = 0; i < words; i++, temp_addr++) {
> +			wait_for_host_ready(info);
> +			writel(*temp_addr, data_addr);
> +		}
> +	}
> +
> +	return words << 1;
> +}
> +
> +static struct scsi_host_template pata_s3c_sht = {
> +	ATA_PIO_SHT(DRV_NAME),
> +};
> +
> +static struct ata_port_operations pata_s3c_port_ops = {
> +	.inherits		= &ata_sff_port_ops,
> +	.sff_check_status	= pata_s3c_check_status,
> +	.sff_tf_load		= pata_s3c_tf_load,
> +	.sff_tf_read		= pata_s3c_tf_read,
> +	.sff_data_xfer		= pata_s3c_data_xfer,
> +	.sff_exec_command	= pata_s3c_exec_command,
> +	.qc_prep		= ata_noop_qc_prep,
> +	.set_piomode		= pata_s3c_set_piomode,
> +};
> +
> +static struct ata_port_operations pata_s5p_port_ops = {
> +	.inherits		= &ata_sff_port_ops,
> +	.qc_prep		= ata_noop_qc_prep,
> +	.set_piomode		= pata_s3c_set_piomode,
> +};
> +
> +static void pata_s3c_enable(void *s3c_ide_regbase, u8 state)
> +{
> +	u32 temp = readl(s3c_ide_regbase + S3C_ATA_CTRL);
> +	temp = state ? temp | 1 : temp & ~1;
you might want ()around the temp |1 and temp & ~1
> +	writel(temp, s3c_ide_regbase + S3C_ATA_CTRL);
> +}
> +
> +static irqreturn_t pata_s3c_irq(int irq, void *dev_instance)
> +{
> +	struct ata_host *host = dev_instance;
> +	struct s3c_ide_info *info = host->private_data;
> +	u32 reg;
> +
> +	reg = readl(info->ide_addr + S3C_ATA_IRQ);
> +	writel(reg, info->ide_addr + S3C_ATA_IRQ);
> +
> +	return ata_sff_interrupt(irq, dev_instance);
> +}
> +
> +static void pata_s3c_setup_timing(struct s3c_ide_info *info)
> +{
> +	uint t1, t2, teoc, i;
> +
> +	uint pio_t1[5] = { 70, 50, 30, 30, 25 };
> +	uint pio_t2[5] = { 290, 290, 290, 80, 70 };
> +	uint pio_teoc[5] = { 240, 43, 10, 70, 25 };
> +
> +	ulong cycle_time = (uint) (1000000000 / clk_get_rate(info->clk));

ulong and uinit? surely pick one. you might want to keep UL and cajhnge
1000000000 to 1000000000UL

> +	for (i = 0; i < 5; i++) {
> +		t1 = (pio_t1[i] / cycle_time) & 0x0f;
> +		t2 = (pio_t2[i] / cycle_time) & 0xff;
> +		teoc = (pio_teoc[i] / cycle_time) & 0xff;
> +		piotime[i] = (teoc << 12) | (t2 << 4) | t1;
> +	}
> +}
> +
> +static void pata_s3c_hwinit(struct s3c_ide_info *info,
> +				struct s3c_ide_platdata *pdata)
> +{
> +	/* Select true-ide as the internal operating mode*/
> +	if (pdata && (pdata->cfg_mode))
> +		pdata->cfg_mode(info->sfr_addr);
> +
> +	switch (info->cpu_type) {
> +	case TYPE_S3C6400:
> +		/* Configure as big endian and enable the i/f*/
> +		pata_s3c_set_endian(info->ide_addr, 1);
> +		pata_s3c_enable(info->ide_addr, 1);
> +		mdelay(100);
> +
> +		/* Remove IRQ Status */
> +		writel(0x1f, info->ide_addr + S3C_ATA_IRQ);
> +		writel(0x1b, info->ide_addr + S3C_ATA_IRQ_MSK);
> +	break;
> +
> +	case TYPE_S5PV210:
> +	case TYPE_S5PC100:
> +		/* Configure as little endian and enable the i/f */
> +		pata_s3c_set_endian(info->ide_addr, 0);
> +		pata_s3c_enable(info->ide_addr, 1);
> +		mdelay(100);
> +
> +		/* Remove IRQ Status */
> +		writel(0x3f, info->ide_addr + S3C_ATA_IRQ);
> +		writel(0x3f, info->ide_addr + S3C_ATA_IRQ_MSK);
> +	break;
> +
> +	default:
> +		BUG();
> +	}
> +}
> +
> +static int __devinit pata_s3c_probe(struct platform_device *pdev)
> +{
> +	struct s3c_ide_platdata *pdata = pdev->dev.platform_data;
> +	struct device *dev = &pdev->dev;
> +	struct s3c_ide_info *info;
> +	struct resource *res;
> +	struct ata_port *ap;
> +	struct ata_host *host;
> +	enum s3c_cpu_type cpu_type;
> +	int ret;
> +
> +	cpu_type = platform_get_device_id(pdev)->driver_data;
> +
> +	info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
> +	if (!info) {
> +		dev_err(dev, "failed to allocate memory for device data\n");
> +		return -ENOMEM;
> +	}
> +
> +	info->irq = platform_get_irq(pdev, 0);
> +	if (info->irq < 0) {
> +		dev_err(dev, "could not obtain irq number\n");
> +		ret = -ENODEV;
> +		goto release_device_mem;
> +	}
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (res == NULL) {
> +		dev_err(dev, "failed to get mem resource\n");
> +		ret = -ENODEV;

if i remeber correctly, you don't want to be returning -ENODEV as
it will be ignored by the uper layers.

> +		goto release_device_mem;
> +	}
> +
> +	info->ide_addr = devm_ioremap(dev,
> +				res->start, res->end - res->start + 1);

resource_size() is your friend here.

> +	if (!info->ide_addr) {
> +		dev_err(dev, "failed to map IO base address\n");
> +		ret = -ENOMEM;
> +		goto release_mem;
> +	}
> +
> +	info->clk = clk_get(&pdev->dev, "cfcon");

need to do something about using explicit names here, should be clk_get(, NULL)

> +	if (IS_ERR(info->clk)) {
> +		dev_err(dev, "failed to get access to cf controller clock\n");
> +		ret = PTR_ERR(info->clk);
> +		info->clk = NULL;
> +		goto unmap;
> +	}
> +
> +	if (clk_enable(info->clk)) {
> +		dev_err(dev, "failed to enable clock source.\n");
> +		goto clkerr;
> +	}
> +
> +	/* init ata host */
> +	host = ata_host_alloc(dev, 1);
> +	if (!host) {
> +		dev_err(dev, "failed to allocate ide host\n");
> +		ret = -ENOMEM;
> +		goto stop_clk;
> +	}
> +
> +	ap = host->ports[0];
> +	ap->flags |= ATA_FLAG_MMIO;
> +	ap->pio_mask = ATA_PIO4;
> +
> +	if (cpu_type == TYPE_S3C6400) {
> +		ap->ops = &pata_s3c_port_ops;
> +		info->sfr_addr = info->ide_addr + 0x1800;
> +		info->ide_addr = info->ide_addr + 0x1900;
> +		info->fifo_status_reg = 0x94;
> +	} else if (cpu_type == TYPE_S5PC100) {
> +		ap->ops = &pata_s5p_port_ops;
> +		info->sfr_addr = info->ide_addr + 0x1800;
> +		info->ide_addr = info->ide_addr + 0x1900;
> +		info->fifo_status_reg = 0x84;
> +	} else {
> +		ap->ops = &pata_s5p_port_ops;
> +		info->fifo_status_reg = 0x84;
> +	}
> +
> +	info->cpu_type = cpu_type;
> +
> +	if (!(info->irq)) {
> +		ap->flags |= ATA_FLAG_PIO_POLLING;
> +		ata_port_desc(ap, "no IRQ, using PIO polling\n");
> +	}
> +
> +	ap->ioaddr.cmd_addr =  info->ide_addr + S3C_ATA_CMD;
> +	ap->ioaddr.data_addr = info->ide_addr + S3C_ATA_PIO_DTR;
> +	ap->ioaddr.error_addr = info->ide_addr + S3C_ATA_PIO_FED;
> +	ap->ioaddr.feature_addr = info->ide_addr + S3C_ATA_PIO_FED;
> +	ap->ioaddr.nsect_addr = info->ide_addr + S3C_ATA_PIO_SCR;
> +	ap->ioaddr.lbal_addr = info->ide_addr + S3C_ATA_PIO_LLR;
> +	ap->ioaddr.lbam_addr = info->ide_addr + S3C_ATA_PIO_LMR;
> +	ap->ioaddr.lbah_addr = info->ide_addr + S3C_ATA_PIO_LHR;
> +	ap->ioaddr.device_addr = info->ide_addr + S3C_ATA_PIO_DVR;
> +	ap->ioaddr.status_addr = info->ide_addr + S3C_ATA_PIO_CSD;
> +	ap->ioaddr.command_addr = info->ide_addr + S3C_ATA_PIO_CSD;
> +	ap->ioaddr.altstatus_addr = info->ide_addr + S3C_ATA_PIO_DAD;
> +	ap->ioaddr.ctl_addr = info->ide_addr + S3C_ATA_PIO_DAD;
> +
> +
> +	ata_port_desc(ap, "mmio cmd 0x%llx ",
> +			(unsigned long long)res->start);
> +
> +	host->private_data = info;
> +
> +	/* Calculates timing parameters for PIO mode */
> +	pata_s3c_setup_timing(info);
> +
> +	if (pdata && (pdata->setup_gpio))
no need for () around the pdata->setup_gpio
> +		pdata->setup_gpio();
> +
> +	/* Set endianness and enable the interface */
> +	pata_s3c_hwinit(info, pdata);
> +
> +	return ata_host_activate(host, info->irq ? info->irq : 0,
> +			info->irq ? pata_s3c_irq : NULL,
> +			IRQF_DISABLED, &pata_s3c_sht);

do you really need to run with IRQs disabled?

> +	dev_set_drvdata(&pdev->dev, host);
> +
> +stop_clk:
> +	clk_disable(info->clk);
> +clkerr:
> +	clk_put(info->clk);
> +unmap:
> +	devm_iounmap(dev, info->ide_addr);
> +release_mem:
> +	release_mem_region(res->start, res->end - res->start + 1);
> +release_device_mem:
> +	kfree(info);
> +return ret;
> +}
> +
> +static int __devexit pata_s3c_remove(struct platform_device *pdev)
> +{
> +	struct ata_host *host = dev_get_drvdata(&pdev->dev);
> +	struct s3c_ide_info *info;
> +	struct resource *res;
> +
> +	if (!host)
> +		return 0;
> +	info = host->private_data;
> +
> +	ata_host_detach(host);
> +
> +	devm_iounmap(&pdev->dev, info->ide_addr);
> +	clk_disable(info->clk);
> +	clk_put(info->clk);
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	release_mem_region(res->start, res->end - res->start + 1);
> +	kfree(info);
> +
> +	return 0;
> +}
> +
> +#ifdef CONFIG_PM
> +static int pata_s3c_suspend(struct platform_device *pdev, pm_message_t state)
> +{
> +	struct ata_host *host = dev_get_drvdata(&pdev->dev);
> +	if (host)
> +		return ata_host_suspend(host, state);
> +	else
> +		return 0;
> +}
> +
> +static int pata_s3c_resume(struct platform_device *pdev)
> +{
> +	struct ata_host *host = dev_get_drvdata(&pdev->dev);
> +	struct s3c_ide_platdata *pdata = pdev->dev.platform_data;
> +	struct s3c_ide_info *info;
> +
> +	info = host->private_data;
> +
> +	if (host) {
> +		pata_s3c_hwinit(info, pdata);
> +		ata_host_resume(host);
> +	}
> +
> +	return 0;
> +}
> +#endif
> +
> +/* driver device registration */
> +static struct platform_device_id pata_s3c_driver_ids[] = {
> +	{
> +		.name		= "s3c6400-pata",
> +		.driver_data	= TYPE_S3C6400,
> +	}, {
> +		.name		= "s5pc100-pata",
> +		.driver_data	= TYPE_S5PC100,
> +	}, {
> +		.name		= "s5pv210-pata",
> +		.driver_data	= TYPE_S5PV210,
> +	},
> +	{ }
> +};
> +
> +MODULE_DEVICE_TABLE(platform, pata_s3c_driver_ids);
> +
> +static struct platform_driver pata_s3c_driver = {
> +	.probe		= pata_s3c_probe,
> +	.remove		= __devexit_p(pata_s3c_remove),
> +	.id_table	= pata_s3c_driver_ids,
> +	.driver		= {
> +		.name		= DRV_NAME,
> +		.owner		= THIS_MODULE,
> +	},
> +#ifdef CONFIG_PM
> +	.suspend	= pata_s3c_suspend,
> +	.resume		= pata_s3c_resume,
> +#endif
please look at using the new pm_ops.

> +};
> +
> +static int __init pata_s3c_init(void)
> +{
> +	return platform_driver_register(&pata_s3c_driver);
> +}
> +
> +static void __exit pata_s3c_exit(void)
> +{
> +	platform_driver_unregister(&pata_s3c_driver);
> +}
> +
> +module_init(pata_s3c_init);
> +module_exit(pata_s3c_exit);
> +
> +MODULE_AUTHOR("Abhilash Kesavan, <a.kesavan@samsung.com>");
> +MODULE_DESCRIPTION("low-level driver for Samsung PATA controller");
> +MODULE_LICENSE("GPL");
> +MODULE_VERSION(DRV_VERSION);
> -- 
> 1.6.2.5

not bad, needs some cleanup.

-- 
Ben

Q:      What's a light-year?
A:      One-third less calories than a regular year.