[MTD] [NAND] eXcite nand flash driver

This is a nand flash driver for the eXcite series of intelligent
cameras manufactured by Basler Vision Technologies AG.
Signed-off-by: Thomas Koeller <thomas.koeller@baslerweb.com>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>

drivers/mtd/nand/Kconfig

@@ -217,6 +217,14 @@ config MTD_NAND_SHARPSL
 	tristate "Support for NAND Flash on Sharp SL Series (C7xx + others)"
 	depends on MTD_NAND && ARCH_PXA
 
+config MTD_NAND_BASLER_EXCITE
+	tristate  "Support for NAND Flash on Basler eXcite"
+	depends on MTD_NAND && BASLER_EXCITE
+	help
+          This enables the driver for the NAND flash device found on the
+          Basler eXcite Smart Camera. If built as a module, the driver
+          will be named "excite_nandflash.ko".
+
 config MTD_NAND_CAFE
        tristate "NAND support for OLPC CAFÉ chip"
        depends on MTD_NAND && PCI

drivers/mtd/nand/Makefile

@@ -24,6 +24,7 @@ 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
+obj-$(CONFIG_MTD_NAND_BASLER_EXCITE)	+= excite_nandflash.o
 
 nand-objs := nand_base.o nand_bbt.o
 cafe_nand-objs := cafe.o cafe_ecc.o

drivers/mtd/nand/excite_nandflash.c

+/*
+*  Copyright (C) 2005 - 2007 by Basler Vision Technologies AG
+*  Author: Thomas Koeller <thomas.koeller.qbaslerweb.com>
+*  Original code by Thies Moeller <thies.moeller@baslerweb.com>
+*
+*  This program is free software; you can redistribute it and/or modify
+*  it under the terms of the GNU General Public License as published by
+*  the Free Software Foundation; either version 2 of the License, or
+*  (at your option) any later version.
+*
+*  This program is distributed in the hope that it will be useful,
+*  but WITHOUT ANY WARRANTY; without even the implied warranty of
+*  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+*  GNU General Public License for more details.
+*
+*  You should have received a copy of the GNU General Public License
+*  along with this program; if not, write to the Free Software
+*  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+*/
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/ioport.h>
+#include <linux/platform_device.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/kernel.h>
+
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/nand.h>
+#include <linux/mtd/nand_ecc.h>
+#include <linux/mtd/partitions.h>
+
+#include <asm/io.h>
+#include <asm/rm9k-ocd.h>
+
+#include <excite_nandflash.h>
+
+#define EXCITE_NANDFLASH_VERSION "0.1"
+
+/* I/O register offsets */
+#define EXCITE_NANDFLASH_DATA_BYTE   0x00
+#define EXCITE_NANDFLASH_STATUS_BYTE 0x0c
+#define EXCITE_NANDFLASH_ADDR_BYTE   0x10
+#define EXCITE_NANDFLASH_CMD_BYTE    0x14
+
+/* prefix for debug output */
+static const char module_id[] = "excite_nandflash";
+
+/*
+ * partition definition
+ */
+static const struct mtd_partition partition_info[] = {
+	{
+		.name = "eXcite RootFS",
+		.offset = 0,
+		.size = MTDPART_SIZ_FULL
+	}
+};
+
+static inline const struct resource *
+excite_nand_get_resource(struct platform_device *d, unsigned long flags,
+			 const char *basename)
+{
+	char buf[80];
+
+	if (snprintf(buf, sizeof buf, "%s_%u", basename, d->id) >= sizeof buf)
+		return NULL;
+	return platform_get_resource_byname(d, flags, buf);
+}
+
+static inline void __iomem *
+excite_nand_map_regs(struct platform_device *d, const char *basename)
+{
+	void *result = NULL;
+	const struct resource *const r =
+	    excite_nand_get_resource(d, IORESOURCE_MEM, basename);
+
+	if (r)
+		result = ioremap_nocache(r->start, r->end + 1 - r->start);
+	return result;
+}
+
+/* controller and mtd information */
+struct excite_nand_drvdata {
+	struct mtd_info board_mtd;
+	struct nand_chip board_chip;
+	void __iomem *regs;
+	void __iomem *tgt;
+};
+
+/* Control function */
+static void excite_nand_control(struct mtd_info *mtd, int cmd,
+				       unsigned int ctrl)
+{
+	struct excite_nand_drvdata * const d =
+	    container_of(mtd, struct excite_nand_drvdata, board_mtd);
+
+	switch (ctrl) {
+	case NAND_CTRL_CHANGE | NAND_CTRL_CLE:
+		d->tgt = d->regs + EXCITE_NANDFLASH_CMD_BYTE;
+		break;
+	case NAND_CTRL_CHANGE | NAND_CTRL_ALE:
+		d->tgt = d->regs + EXCITE_NANDFLASH_ADDR_BYTE;
+		break;
+	case NAND_CTRL_CHANGE | NAND_NCE:
+		d->tgt = d->regs + EXCITE_NANDFLASH_DATA_BYTE;
+		break;
+	}
+
+	if (cmd != NAND_CMD_NONE)
+		__raw_writeb(cmd, d->tgt);
+}
+
+/* Return 0 if flash is busy, 1 if ready */
+static int excite_nand_devready(struct mtd_info *mtd)
+{
+	struct excite_nand_drvdata * const drvdata =
+	    container_of(mtd, struct excite_nand_drvdata, board_mtd);
+
+	return __raw_readb(drvdata->regs + EXCITE_NANDFLASH_STATUS_BYTE);
+}
+
+/*
+ * Called by device layer to remove the driver.
+ * The binding to the mtd and all allocated
+ * resources are released.
+ */
+static int __exit excite_nand_remove(struct device *dev)
+{
+	struct excite_nand_drvdata * const this = dev_get_drvdata(dev);
+
+	dev_set_drvdata(dev, NULL);
+
+	if (unlikely(!this)) {
+		printk(KERN_ERR "%s: called %s without private data!!",
+		       module_id, __func__);
+		return -EINVAL;
+	}
+
+	/* first thing we need to do is release our mtd
+	 * then go through freeing the resource used
+	 */
+	nand_release(&this->board_mtd);
+
+	/* free the common resources */
+	iounmap(this->regs);
+	kfree(this);
+
+	DEBUG(MTD_DEBUG_LEVEL1, "%s: removed\n", module_id);
+	return 0;
+}
+
+/*
+ * Called by device layer when it finds a device matching
+ * one our driver can handle. This code checks to see if
+ * it can allocate all necessary resources then calls the
+ * nand layer to look for devices.
+*/
+static int __init excite_nand_probe(struct device *dev)
+{
+	struct platform_device * const pdev = to_platform_device(dev);
+	struct excite_nand_drvdata *drvdata;	/* private driver data */
+	struct nand_chip *board_chip;	/* private flash chip data */
+	struct mtd_info *board_mtd;	/* mtd info for this board */
+	int scan_res;
+
+	drvdata = kzalloc(sizeof(*drvdata), GFP_KERNEL);
+	if (unlikely(!drvdata)) {
+		printk(KERN_ERR "%s: no memory for drvdata\n",
+		       module_id);
+		return -ENOMEM;
+	}
+
+	/* bind private data into driver */
+	dev_set_drvdata(dev, drvdata);
+
+	/* allocate and map the resource */
+	drvdata->regs =
+		excite_nand_map_regs(pdev, EXCITE_NANDFLASH_RESOURCE_REGS);
+
+	if (unlikely(!drvdata->regs)) {
+		printk(KERN_ERR "%s: cannot reserve register region\n",
+		       module_id);
+		kfree(drvdata);
+		return -ENXIO;
+	}
+	
+	drvdata->tgt = drvdata->regs + EXCITE_NANDFLASH_DATA_BYTE;
+
+	/* initialise our chip */
+	board_chip = &drvdata->board_chip;
+	board_chip->IO_ADDR_R = board_chip->IO_ADDR_W =
+		drvdata->regs + EXCITE_NANDFLASH_DATA_BYTE;
+	board_chip->cmd_ctrl = excite_nand_control;
+	board_chip->dev_ready = excite_nand_devready;
+	board_chip->chip_delay = 25;
+	board_chip->ecc.mode = NAND_ECC_SOFT;
+
+	/* link chip to mtd */
+	board_mtd = &drvdata->board_mtd;
+	board_mtd->priv = board_chip;
+
+	DEBUG(MTD_DEBUG_LEVEL2, "%s: device scan\n", module_id);
+	scan_res = nand_scan(&drvdata->board_mtd, 1);
+
+	if (likely(!scan_res)) {
+		DEBUG(MTD_DEBUG_LEVEL2, "%s: register partitions\n", module_id);
+		add_mtd_partitions(&drvdata->board_mtd, partition_info,
+				   sizeof partition_info / sizeof partition_info[0]);
+	} else {
+		iounmap(drvdata->regs);
+		kfree(drvdata);
+		printk(KERN_ERR "%s: device scan failed\n", module_id);
+		return -EIO;
+	}
+	return 0;
+}
+
+static struct device_driver excite_nand_driver = {
+	.name = "excite_nand",
+	.bus = &platform_bus_type,
+	.probe = excite_nand_probe,
+	.remove = __exit_p(excite_nand_remove)
+};
+
+static int __init excite_nand_init(void)
+{
+	pr_info("Basler eXcite nand flash driver Version "
+		EXCITE_NANDFLASH_VERSION "\n");
+	return driver_register(&excite_nand_driver);
+}
+
+static void __exit excite_nand_exit(void)
+{
+	driver_unregister(&excite_nand_driver);
+}
+
+module_init(excite_nand_init);
+module_exit(excite_nand_exit);
+
+MODULE_AUTHOR("Thomas Koeller <thomas.koeller@baslerweb.com>");
+MODULE_DESCRIPTION("Basler eXcite NAND-Flash driver");
+MODULE_LICENSE("GPL");
+MODULE_VERSION(EXCITE_NANDFLASH_VERSION)