Claim the MPP pins for the NAND flash controller only when it's actually being used. This allows the pins to be shared with the SPI interface which already supports an equivalent on-access MPP reconfiguration.
Reviewed-by: Mark Tomlinson mark.tomlinson@alliedtelesis.co.nz Signed-off-by: Chris Packham judge.packham@gmail.com --- I haven't wrapped this with a configuration option because I think it should be safe to enable by default. It will either re-apply the same MPP configuration that has already been done in the board init or put the MPP pins into the correct mode to access NAND.
I've only got access to one kirkwood based board with NAND flash so I'd appreciate some feedback from someone with access to a few different boards.
From the datasheets I have access to it looks like there is only one
possible MPP configuration for NF_IO[0-7] so that is what I've implemented. I'm not aware of anything using this driver that needs a different MPP config.
Changes in v2: - make nand_config static const
drivers/mtd/nand/kirkwood_nand.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+)
diff --git a/drivers/mtd/nand/kirkwood_nand.c b/drivers/mtd/nand/kirkwood_nand.c index 4fc34d6..d734113 100644 --- a/drivers/mtd/nand/kirkwood_nand.c +++ b/drivers/mtd/nand/kirkwood_nand.c @@ -9,6 +9,7 @@ #include <common.h> #include <asm/io.h> #include <asm/arch/soc.h> +#include <asm/arch/mpp.h> #include <nand.h>
/* NAND Flash Soc registers */ @@ -22,6 +23,8 @@ struct kwnandf_registers { static struct kwnandf_registers *nf_reg = (struct kwnandf_registers *)KW_NANDF_BASE;
+static u32 nand_mpp_backup[9] = { 0 }; + /* * hardware specific access to control-lines/bits */ @@ -49,6 +52,22 @@ static void kw_nand_hwcontrol(struct mtd_info *mtd, int cmd, void kw_nand_select_chip(struct mtd_info *mtd, int chip) { u32 data; + static const u32 nand_config[] = { + MPP0_NF_IO2, + MPP1_NF_IO3, + MPP2_NF_IO4, + MPP3_NF_IO5, + MPP4_NF_IO6, + MPP5_NF_IO7, + MPP18_NF_IO0, + MPP19_NF_IO1, + 0 + }; + + if (chip >= 0) + kirkwood_mpp_conf(nand_config, nand_mpp_backup); + else + kirkwood_mpp_conf(nand_mpp_backup, NULL);
data = readl(&nf_reg->ctrl); data |= NAND_ACTCEBOOT_BIT;