[PATCH] [MTD] NAND: AT91 NAND driver
Andrew Victor
andrew at sanpeople.com
Thu Oct 19 12:24:35 EDT 2006
hi,
I'd like to resubmit the AT91 NAND driver for inclusion in the MTD tree.
This version only differs from version posted by Savin Zlobec (20 Jun
2006) in that the AT91RM9200-specific chip-select / bus setup code has
been moved from the at91_nand.c driver into the processor-specific file.
From: Savin Zlobec <savin at epico.si>
Signed-off-by: Andrew Victor <andrew at sanpeople.com>
diff -urN -x CVS linux-2.6.19-rc2.orig/drivers/mtd/nand/Kconfig linux-2.6.19/drivers/mtd/nand/Kconfig
--- linux-2.6.19-rc2.orig/drivers/mtd/nand/Kconfig Thu Oct 19 16:31:48 2006
+++ linux-2.6.19/drivers/mtd/nand/Kconfig Thu Oct 12 17:07:39 2006
@@ -232,6 +232,13 @@
If you say "m", the module will be called "cs553x_nand.ko".
+config MTD_NAND_AT91
+ bool "Support for NAND Flash / SmartMedia on AT91"
+ depends on MTD_NAND && ARCH_AT91
+ help
+ Enables support for NAND Flash / Smart Media Card interface
+ on Atmel AT91 processors.
+
config MTD_NAND_NANDSIM
tristate "Support for NAND Flash Simulator"
depends on MTD_NAND && MTD_PARTITIONS
diff -urN -x CVS linux-2.6.19-rc2.orig/drivers/mtd/nand/Makefile linux-2.6.19/drivers/mtd/nand/Makefile
--- linux-2.6.19-rc2.orig/drivers/mtd/nand/Makefile Thu Oct 19 16:29:17 2006
+++ linux-2.6.19/drivers/mtd/nand/Makefile Thu Oct 12 17:07:39 2006
@@ -22,5 +22,6 @@
obj-$(CONFIG_MTD_NAND_NANDSIM) += nandsim.o
obj-$(CONFIG_MTD_NAND_CS553X) += cs553x_nand.o
obj-$(CONFIG_MTD_NAND_NDFC) += ndfc.o
+obj-$(CONFIG_MTD_NAND_AT91) += at91_nand.o
nand-objs = nand_base.o nand_bbt.o
diff -urN -x CVS linux-2.6.19-rc2.orig/drivers/mtd/nand/at91_nand.c linux-2.6.19/drivers/mtd/nand/at91_nand.c
--- linux-2.6.19-rc2.orig/drivers/mtd/nand/at91_nand.c Thu Jan 1 02:00:00 1970
+++ linux-2.6.19/drivers/mtd/nand/at91_nand.c Thu Oct 12 17:21:53 2006
@@ -0,0 +1,220 @@
+/*
+ * drivers/mtd/nand/at91_nand.c
+ *
+ * Copyright (C) 2003 Rick Bronson
+ *
+ * Derived from drivers/mtd/nand/autcpu12.c
+ * Copyright (c) 2001 Thomas Gleixner (gleixner at autronix.de)
+ *
+ * Derived from drivers/mtd/spia.c
+ * Copyright (C) 2000 Steven J. Hill (sjhill at cotw.com)
+ *
+ * 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.
+ *
+ */
+
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/nand.h>
+#include <linux/mtd/partitions.h>
+
+#include <asm/io.h>
+#include <asm/sizes.h>
+
+#include <asm/hardware.h>
+#include <asm/arch/board.h>
+#include <asm/arch/gpio.h>
+
+struct at91_nand_host {
+ struct nand_chip nand_chip;
+ struct mtd_info mtd;
+ void __iomem *io_base;
+ struct at91_nand_data *board;
+};
+
+/*
+ * Hardware specific access to control-lines
+ */
+static void at91_nand_cmd_ctrl(struct mtd_info *mtd, int cmd, unsigned int ctrl)
+{
+ struct nand_chip *nand_chip = mtd->priv;
+ struct at91_nand_host *host = nand_chip->priv;
+
+ if (cmd == NAND_CMD_NONE)
+ return;
+
+ if (ctrl & NAND_CLE)
+ writeb(cmd, host->io_base + (1 << host->board->cle));
+ else
+ writeb(cmd, host->io_base + (1 << host->board->ale));
+}
+
+/*
+ * Read the Device Ready pin.
+ */
+static int at91_nand_device_ready(struct mtd_info *mtd)
+{
+ struct nand_chip *nand_chip = mtd->priv;
+ struct at91_nand_host *host = nand_chip->priv;
+
+ return at91_get_gpio_value(host->board->rdy_pin);
+}
+
+/*
+ * Enable NAND.
+ */
+static void at91_nand_enable(struct at91_nand_host *host)
+{
+ if (host->board->enable_pin)
+ at91_set_gpio_value(host->board->enable_pin, 0);
+}
+
+/*
+ * Disable NAND.
+ */
+static void at91_nand_disable(struct at91_nand_host *host)
+{
+ if (host->board->enable_pin)
+ at91_set_gpio_value(host->board->enable_pin, 1);
+}
+
+/*
+ * Probe for the NAND device.
+ */
+static int __init at91_nand_probe(struct platform_device *pdev)
+{
+ struct at91_nand_host *host;
+ struct mtd_info *mtd;
+ struct nand_chip *nand_chip;
+ int res;
+
+#ifdef CONFIG_MTD_PARTITIONS
+ struct mtd_partition *partitions = NULL;
+ int num_partitions = 0;
+#endif
+
+ /* Allocate memory for the device structure (and zero it) */
+ host = kzalloc(sizeof(struct at91_nand_host), GFP_KERNEL);
+ if (!host) {
+ printk(KERN_ERR "at91_nand: failed to allocate device structure.\n");
+ return -ENOMEM;
+ }
+
+ host->io_base = ioremap(pdev->resource[0].start,
+ pdev->resource[0].end - pdev->resource[0].start + 1);
+ if (host->io_base == NULL) {
+ printk(KERN_ERR "at91_nand: ioremap failed\n");
+ kfree(host);
+ return -EIO;
+ }
+
+ mtd = &host->mtd;
+ nand_chip = &host->nand_chip;
+ host->board = pdev->dev.platform_data;
+
+ nand_chip->priv = host; /* link the private data structures */
+ mtd->priv = nand_chip;
+ mtd->owner = THIS_MODULE;
+
+ /* Set address of NAND IO lines */
+ nand_chip->IO_ADDR_R = host->io_base;
+ nand_chip->IO_ADDR_W = host->io_base;
+ nand_chip->cmd_ctrl = at91_nand_cmd_ctrl;
+ nand_chip->dev_ready = at91_nand_device_ready;
+ nand_chip->ecc.mode = NAND_ECC_SOFT; /* enable ECC */
+ nand_chip->chip_delay = 20; /* 20us command delay time */
+
+ platform_set_drvdata(pdev, host);
+ at91_nand_enable(host);
+
+ if (host->board->det_pin) {
+ if (at91_get_gpio_value(host->board->det_pin)) {
+ printk ("No SmartMedia card inserted.\n");
+ res = ENXIO;
+ goto out;
+ }
+ }
+
+ /* Scan to find existance of the device */
+ if (nand_scan(mtd, 1)) {
+ res = -ENXIO;
+ goto out;
+ }
+
+#ifdef CONFIG_MTD_PARTITIONS
+ if (host->board->partition_info)
+ partitions = host->board->partition_info(mtd->size, &num_partitions);
+
+ if ((!partitions) || (num_partitions == 0)) {
+ printk(KERN_ERR "at91_nand: No parititions defined, or unsupported device.\n");
+ res = ENXIO;
+ goto release;
+ }
+
+ res = add_mtd_partitions(mtd, partitions, num_partitions);
+#else
+ res = add_mtd_device(mtd);
+#endif
+
+ if (!res)
+ return res;
+
+release:
+ nand_release(mtd);
+out:
+ at91_nand_disable(host);
+ platform_set_drvdata(pdev, NULL);
+ iounmap(host->io_base);
+ kfree(host);
+ return res;
+}
+
+/*
+ * Remove a NAND device.
+ */
+static int __devexit at91_nand_remove(struct platform_device *pdev)
+{
+ struct at91_nand_host *host = platform_get_drvdata(pdev);
+ struct mtd_info *mtd = &host->mtd;
+
+ nand_release(mtd);
+
+ at91_nand_disable(host);
+
+ iounmap(host->io_base);
+ kfree(host);
+
+ return 0;
+}
+
+static struct platform_driver at91_nand_driver = {
+ .probe = at91_nand_probe,
+ .remove = at91_nand_remove,
+ .driver = {
+ .name = "at91_nand",
+ .owner = THIS_MODULE,
+ },
+};
+
+static int __init at91_nand_init(void)
+{
+ return platform_driver_register(&at91_nand_driver);
+}
+
+
+static void __exit at91_nand_exit(void)
+{
+ platform_driver_unregister(&at91_nand_driver);
+}
+
+
+module_init(at91_nand_init);
+module_exit(at91_nand_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Rick Bronson");
+MODULE_DESCRIPTION("NAND/SmartMedia driver for AT91RM9200");
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