[PATCH] mtd: lantiq: Add NAND support on Lantiq Falcon SoC.

John Crispin
2013-01-30T20:35:14Z

The driver uses plat_nand. As the platform_device is loaded from DT, we need
to lookup the node and attach our falcon specific "struct platform_nand_data"
to it.

Signed-off-by: Thomas Langer <thomas.langer@lantiq.com>
Signed-off-by: John Crispin <blogic@openwrt.org>
---
drivers/mtd/nand/Kconfig | 8 ++++
drivers/mtd/nand/Makefile | 1 +
drivers/mtd/nand/falcon_nand.c | 83 ++++++++++++++++++++++++++++++++++++++++
3 files changed, 92 insertions(+)
create mode 100644 drivers/mtd/nand/falcon_nand.c

diff --git a/drivers/mtd/nand/Kconfig b/drivers/mtd/nand/Kconfig
index 5819eb5..058939d 100644
--- a/drivers/mtd/nand/Kconfig
+++ b/drivers/mtd/nand/Kconfig
@@ -575,4 +575,12 @@ config MTD_NAND_XWAY
Enables support for NAND Flash chips on Lantiq XWAY SoCs. NAND is attached
to the External Bus Unit (EBU).

+config MTD_NAND_FALCON
+ tristate "Support for NAND on Lantiq FALC-ON SoC"
+ depends on LANTIQ && SOC_FALCON
+ select MTD_NAND_PLATFORM
+ help
+ Enables support for NAND Flash chips on Lantiq FALC-ON SoCs. NAND is
+ attached to the External Bus Unit (EBU).
+
endif # MTD_NAND
diff --git a/drivers/mtd/nand/Makefile b/drivers/mtd/nand/Makefile
index d76d912..1a61bf0 100644
--- a/drivers/mtd/nand/Makefile
+++ b/drivers/mtd/nand/Makefile
@@ -53,5 +53,6 @@ obj-$(CONFIG_MTD_NAND_JZ4740) += jz4740_nand.o
obj-$(CONFIG_MTD_NAND_GPMI_NAND) += gpmi-nand/
obj-$(CONFIG_MTD_NAND_XWAY) += xway_nand.o
obj-$(CONFIG_MTD_NAND_BCM47XXNFLASH) += bcm47xxnflash/
+obj-$(CONFIG_MTD_NAND_FALCON) += falcon_nand.o

nand-objs := nand_base.o nand_bbt.o
diff --git a/drivers/mtd/nand/falcon_nand.c b/drivers/mtd/nand/falcon_nand.c
new file mode 100644
index 0000000..13458d3
--- /dev/null
+++ b/drivers/mtd/nand/falcon_nand.c
@@ -0,0 +1,83 @@
+/*
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ *
+ * Copyright (C) 2011 Thomas Langer <thomas.langer@lantiq.com>
+ * Copyright (C) 2011 John Crispin <blogic@openwrt.org>
+ */
+
+#include <linux/mtd/nand.h>
+#include <linux/of_platform.h>
+
+#include <lantiq_soc.h>
+
+/* address lines used for NAND control signals */
+#define NAND_ADDR_ALE 0x10000
+#define NAND_ADDR_CLE 0x20000
+
+/* Ready/Busy Status */
+#define MODCON_STS 0x0002
+
+/* Ready/Busy Status Edge */
+#define MODCON_STSEDGE 0x0004
+#define LTQ_EBU_MODCON 0x000C
+
+static const char const *part_probes[] = { "cmdlinepart", "ofpart", NULL };
+
+static int falcon_nand_ready(struct mtd_info *mtd)
+{
+ u32 modcon = ltq_ebu_r32(LTQ_EBU_MODCON);
+
+ return (((modcon & (MODCON_STS | MODCON_STSEDGE)) ==
+ (MODCON_STS | MODCON_STSEDGE)));
+}
+
+static void falcon_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int ctrl)
+{
+ struct nand_chip *this = mtd->priv;
+ unsigned long nandaddr = (unsigned long) this->IO_ADDR_W;
+
+ if (ctrl & NAND_CTRL_CHANGE) {
+ nandaddr &= ~(NAND_ADDR_ALE | NAND_ADDR_CLE);
+
+ if (ctrl & NAND_CLE)
+ nandaddr |= NAND_ADDR_CLE;
+ if (ctrl & NAND_ALE)
+ nandaddr |= NAND_ADDR_ALE;
+
+ this->IO_ADDR_W = (void __iomem *) nandaddr;
+ }
+
+ if (cmd != NAND_CMD_NONE)
+ writeb(cmd, this->IO_ADDR_W);
+}
+
+static struct platform_nand_data falcon_nand_data = {
+ .chip = {
+ .nr_chips = 1,
+ .chip_delay = 25,
+ .part_probe_types = part_probes,
+ },
+ .ctrl = {
+ .cmd_ctrl = falcon_hwcontrol,
+ .dev_ready = falcon_nand_ready,
+ }
+};
+
+int __init falcon_register_nand(void)
+{
+ struct device_node *node;
+ struct platform_device *pdev;
+
+ node = of_find_compatible_node(NULL, NULL, "lantiq,nand-falcon");
+ if (!node)
+ return -1;
+ pdev = of_find_device_by_node(node);
+ if (pdev)
+ pdev->dev.platform_data = &falcon_nand_data;
+ of_node_put(node);
+ return 0;
+}
+
+arch_initcall(falcon_register_nand);
--
1.7.10.4