mtd: plat_nand: allow platform to set partitions

Add optional callback to allow platform to initialize partitions.

Static partitions on a nand device could vary depending on the size of the
device.  This patch allows an optional platform callback to be used to
setup this partition information at runtime.

Scan order is:
	1) chip.part_probe_types
	2) chip.set_parts
	3) chip.partitions
	4) full mtd device (fallback for no partitions)

Some of the existing nand drivers could possibly be replaced by the
plat_nand driver by using this patch.  These include autcpu12.c and
ts7250.c drivers.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
diff --git a/drivers/mtd/nand/plat_nand.c b/drivers/mtd/nand/plat_nand.c
index 22e0ce7..4e16c6f 100644
--- a/drivers/mtd/nand/plat_nand.c
+++ b/drivers/mtd/nand/plat_nand.c
@@ -95,6 +95,8 @@
 			return 0;
 		}
 	}
+	if (pdata->chip.set_parts)
+		pdata->chip.set_parts(data->mtd.size, &pdata->chip);
 	if (pdata->chip.partitions) {
 		data->parts = pdata->chip.partitions;
 		res = add_mtd_partitions(&data->mtd, data->parts,
diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h
index 7f2d693..4030eba 100644
--- a/include/linux/mtd/nand.h
+++ b/include/linux/mtd/nand.h
@@ -563,6 +563,7 @@
  * @options:		Option flags, e.g. 16bit buswidth
  * @ecclayout:		ecc layout info structure
  * @part_probe_types:	NULL-terminated array of probe types
+ * @set_parts:		platform specific function to set partitions
  * @priv:		hardware controller specific settings
  */
 struct platform_nand_chip {
@@ -574,6 +575,8 @@
 	int			chip_delay;
 	unsigned int		options;
 	const char		**part_probe_types;
+	void			(*set_parts)(uint64_t size,
+					struct platform_nand_chip *chip);
 	void			*priv;
 };