Patchwork [v3,1/1] ata: Add iMX pata support

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Submitter Arnaud Patard (Rtp)
Date July 24, 2011, 6:38 p.m.
Message ID <20110724183823.420642781@rtp-net.org>
Download mbox | patch
Permalink /patch/106561/
State Not Applicable
Delegated to: David Miller
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Comments

Arnaud Patard (Rtp) - July 24, 2011, 6:38 p.m.
Add basic support for pata on iMX. It has been tested only on imx51.
SDMA support will probably be added later so this version supports only
PIO.

v2:
  - enable only when needed IORDY
  - use dev_get_drvdata
v3:
  - add missing clk_put() calls
  - use platform_get_irq()
  - fix resume code to avoid disabling IORDY on resume

Signed-off-by: Arnaud Patard <arnaud.patard@rtp-net.org>


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Sascha Hauer - July 26, 2011, 7:39 a.m.
Hi Arnaud,

On Sun, Jul 24, 2011 at 08:38:07PM +0200, Arnaud Patard wrote:
> Add basic support for pata on iMX. It has been tested only on imx51.
> SDMA support will probably be added later so this version supports only
> PIO.
> 
> v2:
>   - enable only when needed IORDY
>   - use dev_get_drvdata
> v3:
>   - add missing clk_put() calls
>   - use platform_get_irq()
>   - fix resume code to avoid disabling IORDY on resume
> 
> Signed-off-by: Arnaud Patard <arnaud.patard@rtp-net.org>
> Index: linux-2.6-submit/drivers/ata/Kconfig
> ===================================================================
> --- linux-2.6-submit.orig/drivers/ata/Kconfig	2011-07-22 23:29:06.000000000 +0200
> +++ linux-2.6-submit/drivers/ata/Kconfig	2011-07-22 23:30:58.000000000 +0200
> @@ -467,6 +467,15 @@ config PATA_ICSIDE
>  	  interface card.  This is not required for ICS partition support.
>  	  If you are unsure, say N to this.
>  
> +config PATA_IMX
> +	tristate "PATA support for Freescale iMX (Experimental)"
> +	depends on ARCH_MX5 && EXPERIMENTAL

Should this really depend on EXPERIMENTAL? This driver looks pretty
straightforward.

Also, please depend on ARCH_MXC instead. This may make this driver
selectable on some i.MX SoCs which do not support it, but we don't
have to add new ARCH_MX* to this list once a new SoC is supported.

(And no, IMX_HAVE_PLATFORM_BLA_BLA is not a good idea either as we are
converting to the device tree and the Kconfig entries will probably go
in the longer run)


> +
> +static int __devinit pata_imx_probe(struct platform_device *pdev)
> +{
> +	struct ata_host *host;
> +	struct ata_port *ap;
> +	struct pata_imx_priv *priv;
> +	int irq = 0;
> +	struct resource *io_res;
> +
> +	io_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (io_res == NULL)
> +		return -EINVAL;
> +
> +	irq = platform_get_irq(pdev, 0);
> +	if (irq <= 0)
> +		return -EINVAL;
> +
> +	priv = kzalloc(sizeof(struct pata_imx_priv), GFP_KERNEL);
> +	if (!priv)
> +		return -ENOMEM;

Given that you already use devm_ioremap, you can also use devm_kzalloc
here.

> +
> +	priv->clk = clk_get(&pdev->dev, "imx-pata");
> +	if (!priv->clk)

IS_ERR(priv->clk)

(also for the checks below)

Does it really make sense to continue when the clock failed?

> +		dev_warn(&pdev->dev, "Failed to get clock\n");
> +	else
> +		clk_enable(priv->clk);
> +
> +
> +	host = ata_host_alloc(&pdev->dev, 1);
> +	if (!host)
> +		goto free_priv;
> +
> +	host->private_data = priv;
> +	ap = host->ports[0];
> +
> +	ap->ops = &pata_imx_port_ops;
> +	ap->pio_mask = ATA_PIO0;
> +	ap->flags |= ATA_FLAG_SLAVE_POSS;
> +
> +	priv->host_regs = devm_ioremap(&pdev->dev, io_res->start, 0x40);

resource_size() instead of hardcoded 0x40?

> +	ap->ioaddr.cmd_addr = devm_ioremap(&pdev->dev,
> +					io_res->start + PATA_IMX_DRIVE_DATA,
> +					0x20);
> +	ap->ioaddr.ctl_addr = devm_ioremap(&pdev->dev,
> +					io_res->start + PATA_IMX_DRIVE_CONTROL,
> +					0x04);

It looks strange to ioremap the register offsets again. Why not just a

	ap->ioaddr.cmd_addr = priv->host_regs + PATA_IMX_DRIVE_DATA
	ap->ioaddr.ctl_addr = priv->host_regs + PATA_IMX_DRIVE_CONTROL

Hm, probably copied from the pxa driver, but this uses different
resources which makes different ioremaps necessary.

> +	if (!priv->host_regs || !ap->ioaddr.cmd_addr || !ap->ioaddr.ctl_addr) {
> +		dev_err(&pdev->dev, "failed to map IO/CTL base\n");
> +		goto free_priv;
> +	}
> +
> +	ap->ioaddr.altstatus_addr = ap->ioaddr.ctl_addr;
> +
> +
> +	pata_imx_setup_port(&ap->ioaddr);
> +
> +	ata_port_desc(ap, "cmd 0x%llx ctl 0x%llx",
> +		(unsigned long long)io_res->start + PATA_IMX_DRIVE_DATA,
> +		(unsigned long long)io_res->start + PATA_IMX_DRIVE_CONTROL);
> +
> +	/* deassert resets */
> +	__raw_writel(PATA_IMX_ATA_CTRL_FIFO_RST_B |
> +			PATA_IMX_ATA_CTRL_ATA_RST_B,
> +			priv->host_regs + PATA_IMX_ATA_CONTROL);
> +	/* enable interrupts */
> +	__raw_writel(PATA_IMX_ATA_INTR_ATA_INTRQ2,
> +			priv->host_regs + PATA_IMX_ATA_INT_EN);
> +
> +	/* activate */
> +	return ata_host_activate(host, irq, ata_sff_interrupt, 0,
> +				&pata_imx_sht);
> +
> +free_priv:
> +	if (priv->clk) {
> +		clk_disable(priv->clk);
> +		clk_put(priv->clk);
> +	}
> +	kfree(priv);
> +	return -ENOMEM;
> +}
> +
Arnaud Patard (Rtp) - July 26, 2011, 10:04 a.m.
Sascha Hauer <s.hauer@pengutronix.de> writes:

> Hi Arnaud,

Hi,
>
> On Sun, Jul 24, 2011 at 08:38:07PM +0200, Arnaud Patard wrote:
>> Add basic support for pata on iMX. It has been tested only on imx51.
>> SDMA support will probably be added later so this version supports only
>> PIO.
>> 
>> v2:
>>   - enable only when needed IORDY
>>   - use dev_get_drvdata
>> v3:
>>   - add missing clk_put() calls
>>   - use platform_get_irq()
>>   - fix resume code to avoid disabling IORDY on resume
>> 
>> Signed-off-by: Arnaud Patard <arnaud.patard@rtp-net.org>
>> Index: linux-2.6-submit/drivers/ata/Kconfig
>> ===================================================================
>> --- linux-2.6-submit.orig/drivers/ata/Kconfig	2011-07-22 23:29:06.000000000 +0200
>> +++ linux-2.6-submit/drivers/ata/Kconfig	2011-07-22 23:30:58.000000000 +0200
>> @@ -467,6 +467,15 @@ config PATA_ICSIDE
>>  	  interface card.  This is not required for ICS partition support.
>>  	  If you are unsure, say N to this.
>>  
>> +config PATA_IMX
>> +	tristate "PATA support for Freescale iMX (Experimental)"
>> +	depends on ARCH_MX5 && EXPERIMENTAL
>
> Should this really depend on EXPERIMENTAL? This driver looks pretty
> straightforward.

I've been wondering about it but given that it has been tested only on
efika platforms, I prefered to keep it. If you think it's better to
remove it, fine. I'll do it.

>
> Also, please depend on ARCH_MXC instead. This may make this driver
> selectable on some i.MX SoCs which do not support it, but we don't
> have to add new ARCH_MX* to this list once a new SoC is supported.

Well, it's for the same reason as for the EXPERIMENTAL. It's working on
my mx51 platforms, but I've not tested on plateforms like iMX3 (as I
don't have them). Will change.

>
> (And no, IMX_HAVE_PLATFORM_BLA_BLA is not a good idea either as we are
> converting to the device tree and the Kconfig entries will probably go
> in the longer run)
>
>
>> +
>> +static int __devinit pata_imx_probe(struct platform_device *pdev)
>> +{
>> +	struct ata_host *host;
>> +	struct ata_port *ap;
>> +	struct pata_imx_priv *priv;
>> +	int irq = 0;
>> +	struct resource *io_res;
>> +
>> +	io_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>> +	if (io_res == NULL)
>> +		return -EINVAL;
>> +
>> +	irq = platform_get_irq(pdev, 0);
>> +	if (irq <= 0)
>> +		return -EINVAL;
>> +
>> +	priv = kzalloc(sizeof(struct pata_imx_priv), GFP_KERNEL);
>> +	if (!priv)
>> +		return -ENOMEM;
>
> Given that you already use devm_ioremap, you can also use devm_kzalloc
> here.

thanks, will do. I didn't know there was such a function.
>
>> +
>> +	priv->clk = clk_get(&pdev->dev, "imx-pata");
>> +	if (!priv->clk)
>
> IS_ERR(priv->clk)
>
> (also for the checks below)
>
> Does it really make sense to continue when the clock failed?

if you have uboot version like the one I have, the clock will be already
enabled before booting linux so the driver will work. Maybe too fragile ?
I've changed the checks on my local version and about to test it. Let me
know if you think it should really be a failure, in order to avoid
having to send a new version only to make it a failure.

>
>> +		dev_warn(&pdev->dev, "Failed to get clock\n");
>> +	else
>> +		clk_enable(priv->clk);
>> +
>> +
>> +	host = ata_host_alloc(&pdev->dev, 1);
>> +	if (!host)
>> +		goto free_priv;
>> +
>> +	host->private_data = priv;
>> +	ap = host->ports[0];
>> +
>> +	ap->ops = &pata_imx_port_ops;
>> +	ap->pio_mask = ATA_PIO0;
>> +	ap->flags |= ATA_FLAG_SLAVE_POSS;
>> +
>> +	priv->host_regs = devm_ioremap(&pdev->dev, io_res->start, 0x40);
>
> resource_size() instead of hardcoded 0x40?
>
>> +	ap->ioaddr.cmd_addr = devm_ioremap(&pdev->dev,
>> +					io_res->start + PATA_IMX_DRIVE_DATA,
>> +					0x20);
>> +	ap->ioaddr.ctl_addr = devm_ioremap(&pdev->dev,
>> +					io_res->start + PATA_IMX_DRIVE_CONTROL,
>> +					0x04);
>
> It looks strange to ioremap the register offsets again. Why not just a
>
> 	ap->ioaddr.cmd_addr = priv->host_regs + PATA_IMX_DRIVE_DATA
> 	ap->ioaddr.ctl_addr = priv->host_regs + PATA_IMX_DRIVE_CONTROL
>
> Hm, probably copied from the pxa driver, but this uses different
> resources which makes different ioremaps necessary.

There are holes in the register map in the manual, that's why I used
several ioremap. I prefer staying near to what the manual says and avoid
remapping unknown registers.

Thanks,
Arnaud
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Sascha Hauer - July 26, 2011, 12:15 p.m.
On Tue, Jul 26, 2011 at 12:04:27PM +0200, Arnaud Patard wrote:
> Sascha Hauer <s.hauer@pengutronix.de> writes:
> 
> > Hi Arnaud,
> 
> Hi,
> >
> > On Sun, Jul 24, 2011 at 08:38:07PM +0200, Arnaud Patard wrote:
> >> Add basic support for pata on iMX. It has been tested only on imx51.
> >> SDMA support will probably be added later so this version supports only
> >> PIO.
> >> 
> >> v2:
> >>   - enable only when needed IORDY
> >>   - use dev_get_drvdata
> >> v3:
> >>   - add missing clk_put() calls
> >>   - use platform_get_irq()
> >>   - fix resume code to avoid disabling IORDY on resume
> >> 
> >> Signed-off-by: Arnaud Patard <arnaud.patard@rtp-net.org>
> >> Index: linux-2.6-submit/drivers/ata/Kconfig
> >> ===================================================================
> >> --- linux-2.6-submit.orig/drivers/ata/Kconfig	2011-07-22 23:29:06.000000000 +0200
> >> +++ linux-2.6-submit/drivers/ata/Kconfig	2011-07-22 23:30:58.000000000 +0200
> >> @@ -467,6 +467,15 @@ config PATA_ICSIDE
> >>  	  interface card.  This is not required for ICS partition support.
> >>  	  If you are unsure, say N to this.
> >>  
> >> +config PATA_IMX
> >> +	tristate "PATA support for Freescale iMX (Experimental)"
> >> +	depends on ARCH_MX5 && EXPERIMENTAL
> >
> > Should this really depend on EXPERIMENTAL? This driver looks pretty
> > straightforward.
> 
> I've been wondering about it but given that it has been tested only on
> efika platforms, I prefered to keep it. If you think it's better to
> remove it, fine. I'll do it.

Only the efika platform registers the device, so there's no risk to
harm other boards.

> >
> > IS_ERR(priv->clk)
> >
> > (also for the checks below)
> >
> > Does it really make sense to continue when the clock failed?
> 
> if you have uboot version like the one I have, the clock will be already
> enabled before booting linux so the driver will work. Maybe too fragile ?
> I've changed the checks on my local version and about to test it. Let me
> know if you think it should really be a failure, in order to avoid
> having to send a new version only to make it a failure.

Yes, it should be a failure.

> >> +	ap->ioaddr.cmd_addr = devm_ioremap(&pdev->dev,
> >> +					io_res->start + PATA_IMX_DRIVE_DATA,
> >> +					0x20);
> >> +	ap->ioaddr.ctl_addr = devm_ioremap(&pdev->dev,
> >> +					io_res->start + PATA_IMX_DRIVE_CONTROL,
> >> +					0x04);
> >
> > It looks strange to ioremap the register offsets again. Why not just a
> >
> > 	ap->ioaddr.cmd_addr = priv->host_regs + PATA_IMX_DRIVE_DATA
> > 	ap->ioaddr.ctl_addr = priv->host_regs + PATA_IMX_DRIVE_CONTROL
> >
> > Hm, probably copied from the pxa driver, but this uses different
> > resources which makes different ioremaps necessary.
> 
> There are holes in the register map in the manual, that's why I used
> several ioremap. I prefer staying near to what the manual says and avoid
> remapping unknown registers.

Having holes in the register space is a very common case, no need to do
several ioremaps. Besides, ioremap will give you a whole page anyway.

Sascha

Patch

Index: linux-2.6-submit/drivers/ata/Kconfig
===================================================================
--- linux-2.6-submit.orig/drivers/ata/Kconfig	2011-07-22 23:29:06.000000000 +0200
+++ linux-2.6-submit/drivers/ata/Kconfig	2011-07-22 23:30:58.000000000 +0200
@@ -467,6 +467,15 @@  config PATA_ICSIDE
 	  interface card.  This is not required for ICS partition support.
 	  If you are unsure, say N to this.
 
+config PATA_IMX
+	tristate "PATA support for Freescale iMX (Experimental)"
+	depends on ARCH_MX5 && EXPERIMENTAL
+	help
+	  This option enables support for the PATA host available on Freescale
+          iMX SoCs.
+
+	  If unsure, say N.
+
 config PATA_IT8213
 	tristate "IT8213 PATA support (Experimental)"
 	depends on PCI && EXPERIMENTAL
Index: linux-2.6-submit/drivers/ata/Makefile
===================================================================
--- linux-2.6-submit.orig/drivers/ata/Makefile	2011-07-22 23:29:06.000000000 +0200
+++ linux-2.6-submit/drivers/ata/Makefile	2011-07-22 23:30:58.000000000 +0200
@@ -48,6 +48,7 @@  obj-$(CONFIG_PATA_HPT37X)	+= pata_hpt37x
 obj-$(CONFIG_PATA_HPT3X2N)	+= pata_hpt3x2n.o
 obj-$(CONFIG_PATA_HPT3X3)	+= pata_hpt3x3.o
 obj-$(CONFIG_PATA_ICSIDE)	+= pata_icside.o
+obj-$(CONFIG_PATA_IMX)		+= pata_imx.o
 obj-$(CONFIG_PATA_IT8213)	+= pata_it8213.o
 obj-$(CONFIG_PATA_IT821X)	+= pata_it821x.o
 obj-$(CONFIG_PATA_JMICRON)	+= pata_jmicron.o
Index: linux-2.6-submit/drivers/ata/pata_imx.c
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ linux-2.6-submit/drivers/ata/pata_imx.c	2011-07-24 20:35:24.000000000 +0200
@@ -0,0 +1,263 @@ 
+/*
+ * Freescale iMX PATA driver
+ *
+ * Copyright (C) 2011 Arnaud Patard <arnaud.patard@rtp-net.org>
+ *
+ * Based on pata_platform - Copyright (C) 2006 - 2007  Paul Mundt
+ *
+ * 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.
+ *
+ * TODO:
+ * - dmaengine support
+ * - check if timing stuff needed
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/blkdev.h>
+#include <scsi/scsi_host.h>
+#include <linux/ata.h>
+#include <linux/libata.h>
+#include <linux/platform_device.h>
+#include <linux/clk.h>
+
+#define DRV_NAME "pata_imx"
+
+#define PATA_IMX_ATA_CONTROL		0x24
+#define PATA_IMX_ATA_CTRL_FIFO_RST_B	(1<<7)
+#define PATA_IMX_ATA_CTRL_ATA_RST_B	(1<<6)
+#define PATA_IMX_ATA_CTRL_IORDY_EN	(1<<0)
+#define PATA_IMX_ATA_INT_EN		0x2C
+#define PATA_IMX_ATA_INTR_ATA_INTRQ2	(1<<3)
+#define PATA_IMX_DRIVE_DATA		0xA0
+#define PATA_IMX_DRIVE_CONTROL		0xD8
+
+struct pata_imx_priv {
+	struct clk *clk;
+	/* timings/interrupt/control regs */
+	u8 *host_regs;
+	u32 ata_ctl;
+};
+
+static int pata_imx_set_mode(struct ata_link *link, struct ata_device **unused)
+{
+	struct ata_device *dev;
+	struct ata_port *ap = link->ap;
+	struct pata_imx_priv *priv = ap->host->private_data;
+	u32 val;
+
+	ata_for_each_dev(dev, link, ENABLED) {
+		dev->pio_mode = dev->xfer_mode = XFER_PIO_0;
+		dev->xfer_shift = ATA_SHIFT_PIO;
+		dev->flags |= ATA_DFLAG_PIO;
+
+		val = __raw_readl(priv->host_regs + PATA_IMX_ATA_CONTROL);
+		if (ata_pio_need_iordy(dev))
+			val |= PATA_IMX_ATA_CTRL_IORDY_EN;
+		else
+			val &= ~PATA_IMX_ATA_CTRL_IORDY_EN;
+		__raw_writel(val, priv->host_regs + PATA_IMX_ATA_CONTROL);
+
+		ata_dev_printk(dev, KERN_INFO, "configured for PIO\n");
+	}
+	return 0;
+}
+
+static struct scsi_host_template pata_imx_sht = {
+	ATA_PIO_SHT(DRV_NAME),
+};
+
+static struct ata_port_operations pata_imx_port_ops = {
+	.inherits		= &ata_sff_port_ops,
+	.sff_data_xfer		= ata_sff_data_xfer_noirq,
+	.cable_detect		= ata_cable_unknown,
+	.set_mode		= pata_imx_set_mode,
+};
+
+static void pata_imx_setup_port(struct ata_ioports *ioaddr)
+{
+	/* Fixup the port shift for platforms that need it */
+	ioaddr->data_addr	= ioaddr->cmd_addr + (ATA_REG_DATA    << 2);
+	ioaddr->error_addr	= ioaddr->cmd_addr + (ATA_REG_ERR     << 2);
+	ioaddr->feature_addr	= ioaddr->cmd_addr + (ATA_REG_FEATURE << 2);
+	ioaddr->nsect_addr	= ioaddr->cmd_addr + (ATA_REG_NSECT   << 2);
+	ioaddr->lbal_addr	= ioaddr->cmd_addr + (ATA_REG_LBAL    << 2);
+	ioaddr->lbam_addr	= ioaddr->cmd_addr + (ATA_REG_LBAM    << 2);
+	ioaddr->lbah_addr	= ioaddr->cmd_addr + (ATA_REG_LBAH    << 2);
+	ioaddr->device_addr	= ioaddr->cmd_addr + (ATA_REG_DEVICE  << 2);
+	ioaddr->status_addr	= ioaddr->cmd_addr + (ATA_REG_STATUS  << 2);
+	ioaddr->command_addr	= ioaddr->cmd_addr + (ATA_REG_CMD     << 2);
+}
+
+static int __devinit pata_imx_probe(struct platform_device *pdev)
+{
+	struct ata_host *host;
+	struct ata_port *ap;
+	struct pata_imx_priv *priv;
+	int irq = 0;
+	struct resource *io_res;
+
+	io_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (io_res == NULL)
+		return -EINVAL;
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq <= 0)
+		return -EINVAL;
+
+	priv = kzalloc(sizeof(struct pata_imx_priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->clk = clk_get(&pdev->dev, "imx-pata");
+	if (!priv->clk)
+		dev_warn(&pdev->dev, "Failed to get clock\n");
+	else
+		clk_enable(priv->clk);
+
+
+	host = ata_host_alloc(&pdev->dev, 1);
+	if (!host)
+		goto free_priv;
+
+	host->private_data = priv;
+	ap = host->ports[0];
+
+	ap->ops = &pata_imx_port_ops;
+	ap->pio_mask = ATA_PIO0;
+	ap->flags |= ATA_FLAG_SLAVE_POSS;
+
+	priv->host_regs = devm_ioremap(&pdev->dev, io_res->start, 0x40);
+	ap->ioaddr.cmd_addr = devm_ioremap(&pdev->dev,
+					io_res->start + PATA_IMX_DRIVE_DATA,
+					0x20);
+	ap->ioaddr.ctl_addr = devm_ioremap(&pdev->dev,
+					io_res->start + PATA_IMX_DRIVE_CONTROL,
+					0x04);
+	if (!priv->host_regs || !ap->ioaddr.cmd_addr || !ap->ioaddr.ctl_addr) {
+		dev_err(&pdev->dev, "failed to map IO/CTL base\n");
+		goto free_priv;
+	}
+
+	ap->ioaddr.altstatus_addr = ap->ioaddr.ctl_addr;
+
+
+	pata_imx_setup_port(&ap->ioaddr);
+
+	ata_port_desc(ap, "cmd 0x%llx ctl 0x%llx",
+		(unsigned long long)io_res->start + PATA_IMX_DRIVE_DATA,
+		(unsigned long long)io_res->start + PATA_IMX_DRIVE_CONTROL);
+
+	/* deassert resets */
+	__raw_writel(PATA_IMX_ATA_CTRL_FIFO_RST_B |
+			PATA_IMX_ATA_CTRL_ATA_RST_B,
+			priv->host_regs + PATA_IMX_ATA_CONTROL);
+	/* enable interrupts */
+	__raw_writel(PATA_IMX_ATA_INTR_ATA_INTRQ2,
+			priv->host_regs + PATA_IMX_ATA_INT_EN);
+
+	/* activate */
+	return ata_host_activate(host, irq, ata_sff_interrupt, 0,
+				&pata_imx_sht);
+
+free_priv:
+	if (priv->clk) {
+		clk_disable(priv->clk);
+		clk_put(priv->clk);
+	}
+	kfree(priv);
+	return -ENOMEM;
+}
+
+static int __devexit pata_imx_remove(struct platform_device *pdev)
+{
+	struct ata_host *host = dev_get_drvdata(&pdev->dev);
+	struct pata_imx_priv *priv = host->private_data;
+
+	ata_host_detach(host);
+
+	__raw_writel(0, priv->host_regs + PATA_IMX_ATA_INT_EN);
+
+	if (priv->clk) {
+		clk_disable(priv->clk);
+		clk_put(priv->clk);
+	}
+
+	kfree(priv);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int pata_imx_suspend(struct device *dev)
+{
+	struct ata_host *host = dev_get_drvdata(dev);
+	struct pata_imx_priv *priv = host->private_data;
+	int ret;
+
+	ret = ata_host_suspend(host, PMSG_SUSPEND);
+	if (!ret) {
+		__raw_writel(0, priv->host_regs + PATA_IMX_ATA_INT_EN);
+		priv->ata_ctl =
+			__raw_readl(priv->host_regs + PATA_IMX_ATA_CONTROL);
+		if (priv->clk)
+			clk_disable(priv->clk);
+	}
+
+	return ret;
+}
+
+static int pata_imx_resume(struct device *dev)
+{
+	struct ata_host *host = dev_get_drvdata(dev);
+	struct pata_imx_priv *priv = host->private_data;
+
+	if (priv->clk)
+		clk_enable(priv->clk);
+
+	__raw_writel(priv->ata_ctl, priv->host_regs + PATA_IMX_ATA_CONTROL);
+
+	__raw_writel(PATA_IMX_ATA_INTR_ATA_INTRQ2,
+			priv->host_regs + PATA_IMX_ATA_INT_EN);
+
+	ata_host_resume(host);
+
+	return 0;
+}
+
+static const struct dev_pm_ops pata_imx_pm_ops = {
+	.suspend	= pata_imx_suspend,
+	.resume		= pata_imx_resume,
+};
+#endif
+
+static struct platform_driver pata_imx_driver = {
+	.probe		= pata_imx_probe,
+	.remove		= __devexit_p(pata_imx_remove),
+	.driver = {
+		.name		= DRV_NAME,
+		.owner		= THIS_MODULE,
+#ifdef CONFIG_PM
+		.pm		= &pata_imx_pm_ops,
+#endif
+	},
+};
+
+static int __init pata_imx_init(void)
+{
+	return platform_driver_register(&pata_imx_driver);
+}
+
+static void __exit pata_imx_exit(void)
+{
+	platform_driver_unregister(&pata_imx_driver);
+}
+module_init(pata_imx_init);
+module_exit(pata_imx_exit);
+
+MODULE_AUTHOR("Arnaud Patard <arnaud.patard@rtp-net.org>");
+MODULE_DESCRIPTION("low-level driver for iMX PATA");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:" DRV_NAME);