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/*
* drivers/mtd/nand/at91_nand.c
*
* Copyright (C) 2003 Rick Bronson
*
* Derived from drivers/mtd/nand/autcpu12.c
* Copyright (c) 2001 Thomas Gleixner (gleixner@autronix.de)
*
* Derived from drivers/mtd/spia.c
* Copyright (C) 2000 Steven J. Hill (sjhill@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/arch/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_hwcontrol(struct mtd_info *mtd, int cmd)
{
struct nand_chip *nand_chip = mtd->priv;
struct at91_nand_host *host = nand_chip->priv;
switch(cmd) {
case NAND_CTL_SETCLE:
nand_chip->IO_ADDR_W = host->io_base + (1 << host->board->cle);
break;
case NAND_CTL_CLRCLE:
nand_chip->IO_ADDR_W = host->io_base;
break;
case NAND_CTL_SETALE:
nand_chip->IO_ADDR_W = host->io_base + (1 << host->board->ale);
break;
case NAND_CTL_CLRALE:
nand_chip->IO_ADDR_W = host->io_base;
break;
case NAND_CTL_SETNCE:
break;
case NAND_CTL_CLRNCE:
break;
}
}
/*
* 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 and detect card.
*/
static void at91_nand_enable(struct at91_nand_host *host)
{
unsigned int csa;
/* Setup Smart Media, first enable the address range of CS3 */
csa = at91_sys_read(AT91_EBI_CSA);
at91_sys_write(AT91_EBI_CSA, csa | AT91_EBI_CS3A_SMC_SMARTMEDIA);
/* set the bus interface characteristics */
at91_sys_write(AT91_SMC_CSR(3), AT91_SMC_ACSS_STD | AT91_SMC_DBW_8 | AT91_SMC_WSEN
| AT91_SMC_NWS_(5)
| AT91_SMC_TDF_(1)
| AT91_SMC_RWSETUP_(0) /* tDS Data Set up Time 30 - ns */
| AT91_SMC_RWHOLD_(1) /* tDH Data Hold Time 20 - ns */
);
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;
/* Set address of NAND IO lines */
nand_chip->IO_ADDR_R = host->io_base;
nand_chip->IO_ADDR_W = host->io_base;
nand_chip->hwcontrol = at91_nand_hwcontrol;
nand_chip->dev_ready = at91_nand_device_ready;
nand_chip->eccmode = 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 out;
}
res = add_mtd_partitions(mtd, partitions, num_partitions);
#else
res = add_mtd_device(mtd);
#endif
out:
if (res) {
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;
del_mtd_partitions(mtd);
del_mtd_device(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("Glue layer for SmartMediaCard on ATMEL AT91RM9200");
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