android_kernel_samsung_msm8976/drivers/mtd/nand/edb7312.c
Roland Stigge 9d7b4b5562 [MTD] [NAND] Fix refactoring of EDB7312 hwcontrol function.
The patch ensures that the current code (kernel 2.6.22) uses the bits
like the code prior to the refactoring. The variable "bits" is employed
in a useful way now.

Signed-off-by: Roland Stigge <stigge@antcom.de>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2007-08-02 21:46:07 +01:00

212 lines
5.2 KiB
C

/*
* drivers/mtd/nand/edb7312.c
*
* Copyright (C) 2002 Marius Gröger (mag@sysgo.de)
*
* Derived from drivers/mtd/nand/autcpu12.c
* Copyright (c) 2001 Thomas Gleixner (gleixner@autronix.de)
*
* $Id: edb7312.c,v 1.12 2005/11/07 11:14:30 gleixner Exp $
*
* 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.
*
* Overview:
* This is a device driver for the NAND flash device found on the
* CLEP7312 board which utilizes the Toshiba TC58V64AFT part. This is
* a 64Mibit (8MiB x 8 bits) NAND flash device.
*/
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/nand.h>
#include <linux/mtd/partitions.h>
#include <asm/io.h>
#include <asm/arch/hardware.h> /* for CLPS7111_VIRT_BASE */
#include <asm/sizes.h>
#include <asm/hardware/clps7111.h>
/*
* MTD structure for EDB7312 board
*/
static struct mtd_info *ep7312_mtd = NULL;
/*
* Values specific to the EDB7312 board (used with EP7312 processor)
*/
#define EP7312_FIO_PBASE 0x10000000 /* Phys address of flash */
#define EP7312_PXDR 0x0001 /*
* IO offset to Port B data register
* where the CLE, ALE and NCE pins
* are wired to.
*/
#define EP7312_PXDDR 0x0041 /*
* IO offset to Port B data direction
* register so we can control the IO
* lines.
*/
/*
* Module stuff
*/
static unsigned long ep7312_fio_pbase = EP7312_FIO_PBASE;
static void __iomem *ep7312_pxdr = (void __iomem *)EP7312_PXDR;
static void __iomem *ep7312_pxddr = (void __iomem *)EP7312_PXDDR;
#ifdef CONFIG_MTD_PARTITIONS
/*
* Define static partitions for flash device
*/
static struct mtd_partition partition_info[] = {
{.name = "EP7312 Nand Flash",
.offset = 0,
.size = 8 * 1024 * 1024}
};
#define NUM_PARTITIONS 1
#endif
/*
* hardware specific access to control-lines
*
* NAND_NCE: bit 0 -> bit 6 (bit 7 = 1)
* NAND_CLE: bit 1 -> bit 4
* NAND_ALE: bit 2 -> bit 5
*/
static void ep7312_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int ctrl)
{
struct nand_chip *chip = mtd->priv;
if (ctrl & NAND_CTRL_CHANGE) {
unsigned char bits = 0x80;
bits |= (ctrl & (NAND_CLE | NAND_ALE)) << 3;
bits |= (ctrl & NAND_NCE) ? 0x00 : 0x40;
clps_writeb((clps_readb(ep7312_pxdr) & 0xF0) | bits,
ep7312_pxdr);
}
if (cmd != NAND_CMD_NONE)
writeb(cmd, chip->IO_ADDR_W);
}
/*
* read device ready pin
*/
static int ep7312_device_ready(struct mtd_info *mtd)
{
return 1;
}
#ifdef CONFIG_MTD_PARTITIONS
const char *part_probes[] = { "cmdlinepart", NULL };
#endif
/*
* Main initialization routine
*/
static int __init ep7312_init(void)
{
struct nand_chip *this;
const char *part_type = 0;
int mtd_parts_nb = 0;
struct mtd_partition *mtd_parts = 0;
void __iomem *ep7312_fio_base;
/* Allocate memory for MTD device structure and private data */
ep7312_mtd = kmalloc(sizeof(struct mtd_info) + sizeof(struct nand_chip), GFP_KERNEL);
if (!ep7312_mtd) {
printk("Unable to allocate EDB7312 NAND MTD device structure.\n");
return -ENOMEM;
}
/* map physical adress */
ep7312_fio_base = ioremap(ep7312_fio_pbase, SZ_1K);
if (!ep7312_fio_base) {
printk("ioremap EDB7312 NAND flash failed\n");
kfree(ep7312_mtd);
return -EIO;
}
/* Get pointer to private data */
this = (struct nand_chip *)(&ep7312_mtd[1]);
/* Initialize structures */
memset(ep7312_mtd, 0, sizeof(struct mtd_info));
memset(this, 0, sizeof(struct nand_chip));
/* Link the private data with the MTD structure */
ep7312_mtd->priv = this;
ep7312_mtd->owner = THIS_MODULE;
/*
* Set GPIO Port B control register so that the pins are configured
* to be outputs for controlling the NAND flash.
*/
clps_writeb(0xf0, ep7312_pxddr);
/* insert callbacks */
this->IO_ADDR_R = ep7312_fio_base;
this->IO_ADDR_W = ep7312_fio_base;
this->cmd_ctrl = ep7312_hwcontrol;
this->dev_ready = ep7312_device_ready;
/* 15 us command delay time */
this->chip_delay = 15;
/* Scan to find existence of the device */
if (nand_scan(ep7312_mtd, 1)) {
iounmap((void *)ep7312_fio_base);
kfree(ep7312_mtd);
return -ENXIO;
}
#ifdef CONFIG_MTD_PARTITIONS
ep7312_mtd->name = "edb7312-nand";
mtd_parts_nb = parse_mtd_partitions(ep7312_mtd, part_probes, &mtd_parts, 0);
if (mtd_parts_nb > 0)
part_type = "command line";
else
mtd_parts_nb = 0;
#endif
if (mtd_parts_nb == 0) {
mtd_parts = partition_info;
mtd_parts_nb = NUM_PARTITIONS;
part_type = "static";
}
/* Register the partitions */
printk(KERN_NOTICE "Using %s partition definition\n", part_type);
add_mtd_partitions(ep7312_mtd, mtd_parts, mtd_parts_nb);
/* Return happy */
return 0;
}
module_init(ep7312_init);
/*
* Clean up routine
*/
static void __exit ep7312_cleanup(void)
{
struct nand_chip *this = (struct nand_chip *)&ep7312_mtd[1];
/* Release resources, unregister device */
nand_release(ap7312_mtd);
/* Release io resource */
iounmap(this->IO_ADDR_R);
/* Free the MTD device structure */
kfree(ep7312_mtd);
}
module_exit(ep7312_cleanup);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Marius Groeger <mag@sysgo.de>");
MODULE_DESCRIPTION("MTD map driver for Cogent EDB7312 board");