MTD: NAND: JZ4740: Multi-bank support with autodetection

The platform data can now specify which external memory banks to probe
for NAND chips, and in which order. Banks that contain a NAND are used
and the other banks are freed.

Squashed version of development done in jz-2.6.38 branch.
Original patch by Lars-Peter Clausen with some bug fixes from me.
Thanks to Paul Cercueil for the initial autodetection patch.

Signed-off-by: Maarten ter Huurne <maarten@treewalker.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/3560/
Acked-By: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

2 files changed, 23 insertions, 1 deletions

diff --git a/arch/mips/include/asm/mach-jz4740/jz4740_nand.h b/arch/mips/include/asm/mach-jz4740/jz4740_nand.h
index bb5b9a4e29c8..986982db7c38 100644
--- a/arch/mips/include/asm/mach-jz4740/jz4740_nand.h
+++ b/arch/mips/include/asm/mach-jz4740/jz4740_nand.h
@@ -19,6 +19,8 @@
 #include <linux/mtd/nand.h>
 #include <linux/mtd/partitions.h>
 
+#define JZ_NAND_NUM_BANKS 4
+
 struct jz_nand_platform_data {
         int                     num_partitions;
         struct mtd_partition    *partitions;
@@ -27,6 +29,8 @@ struct jz_nand_platform_data {
 
         unsigned int busy_gpio;
 
+        unsigned char banks[JZ_NAND_NUM_BANKS];
+
         void (*ident_callback)(struct platform_device *, struct nand_chip *,
                                 struct mtd_partition **, int *num_partitions);
 };
diff --git a/arch/mips/jz4740/platform.c b/arch/mips/jz4740/platform.c
index 10929e2bc6d8..e342ed4cbd43 100644
--- a/arch/mips/jz4740/platform.c
+++ b/arch/mips/jz4740/platform.c
@@ -157,11 +157,29 @@ static struct resource jz4740_nand_resources[] = {
                 .flags  = IORESOURCE_MEM,
         },
         {
-                .name   = "bank",
+                .name   = "bank1",
                 .start  = 0x18000000,
                 .end    = 0x180C0000 - 1,
                 .flags = IORESOURCE_MEM,
         },
+        {
+                .name   = "bank2",
+                .start  = 0x14000000,
+                .end    = 0x140C0000 - 1,
+                .flags = IORESOURCE_MEM,
+        },
+        {
+                .name   = "bank3",
+                .start  = 0x0C000000,
+                .end    = 0x0C0C0000 - 1,
+                .flags = IORESOURCE_MEM,
+        },
+        {
+                .name   = "bank4",
+                .start  = 0x08000000,
+                .end    = 0x080C0000 - 1,
+                .flags = IORESOURCE_MEM,
+        },
 };
 
 struct platform_device jz4740_nand_device = {