ata: Add iMX pata support

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
v4:
  - Remove EXPERIMENTAL and switch to depends on ARCH_MXC
  - Use devm_kzalloc()
  - make clock a must-have
  - Use only 1 ioremap

Signed-off-by: Arnaud Patard <arnaud.patard@rtp-net.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/drivers/ata/Kconfig b/drivers/ata/Kconfig
index ca3e6be..5987e0b 100644
--- a/drivers/ata/Kconfig
+++ b/drivers/ata/Kconfig
@@ -468,6 +468,15 @@
 	  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"
+	depends on ARCH_MXC
+	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