linux/drivers/mtd/nand/ams-delta.c
Jonathan McDowell fb8d81e477 [PATCH] MTD NAND: Fix ams-delta after core conversion
The recent hwctrl core conversion for MTD NAND devices broke the Amstrad
Delta driver.  This fixes it up and uses the existing control line defines
rather than unclear magic numbers.

Signed-off-by: Jonathan McDowell <noodles@earth.li>
Acked-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-08-27 11:01:30 -07:00

239 lines
5.8 KiB
C

/*
* drivers/mtd/nand/ams-delta.c
*
* Copyright (C) 2006 Jonathan McDowell <noodles@earth.li>
*
* Derived from drivers/mtd/toto.c
*
* 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
* Amstrad E3 (Delta).
*/
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/delay.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>
#include <asm/sizes.h>
#include <asm/arch/gpio.h>
#include <asm/arch/board-ams-delta.h>
/*
* MTD structure for E3 (Delta)
*/
static struct mtd_info *ams_delta_mtd = NULL;
#define NAND_MASK (AMS_DELTA_LATCH2_NAND_NRE | AMS_DELTA_LATCH2_NAND_NWE | AMS_DELTA_LATCH2_NAND_CLE | AMS_DELTA_LATCH2_NAND_ALE | AMS_DELTA_LATCH2_NAND_NCE | AMS_DELTA_LATCH2_NAND_NWP)
/*
* Define partitions for flash devices
*/
static struct mtd_partition partition_info[] = {
{ .name = "Kernel",
.offset = 0,
.size = 3 * SZ_1M + SZ_512K },
{ .name = "u-boot",
.offset = 3 * SZ_1M + SZ_512K,
.size = SZ_256K },
{ .name = "u-boot params",
.offset = 3 * SZ_1M + SZ_512K + SZ_256K,
.size = SZ_256K },
{ .name = "Amstrad LDR",
.offset = 4 * SZ_1M,
.size = SZ_256K },
{ .name = "File system",
.offset = 4 * SZ_1M + 1 * SZ_256K,
.size = 27 * SZ_1M },
{ .name = "PBL reserved",
.offset = 32 * SZ_1M - 3 * SZ_256K,
.size = 3 * SZ_256K },
};
static void ams_delta_write_byte(struct mtd_info *mtd, u_char byte)
{
struct nand_chip *this = mtd->priv;
omap_writew(0, (OMAP_MPUIO_BASE + OMAP_MPUIO_IO_CNTL));
omap_writew(byte, this->IO_ADDR_W);
ams_delta_latch2_write(AMS_DELTA_LATCH2_NAND_NWE, 0);
ndelay(40);
ams_delta_latch2_write(AMS_DELTA_LATCH2_NAND_NWE,
AMS_DELTA_LATCH2_NAND_NWE);
}
static u_char ams_delta_read_byte(struct mtd_info *mtd)
{
u_char res;
struct nand_chip *this = mtd->priv;
ams_delta_latch2_write(AMS_DELTA_LATCH2_NAND_NRE, 0);
ndelay(40);
omap_writew(~0, (OMAP_MPUIO_BASE + OMAP_MPUIO_IO_CNTL));
res = omap_readw(this->IO_ADDR_R);
ams_delta_latch2_write(AMS_DELTA_LATCH2_NAND_NRE,
AMS_DELTA_LATCH2_NAND_NRE);
return res;
}
static void ams_delta_write_buf(struct mtd_info *mtd, const u_char *buf,
int len)
{
int i;
for (i=0; i<len; i++)
ams_delta_write_byte(mtd, buf[i]);
}
static void ams_delta_read_buf(struct mtd_info *mtd, u_char *buf, int len)
{
int i;
for (i=0; i<len; i++)
buf[i] = ams_delta_read_byte(mtd);
}
static int ams_delta_verify_buf(struct mtd_info *mtd, const u_char *buf,
int len)
{
int i;
for (i=0; i<len; i++)
if (buf[i] != ams_delta_read_byte(mtd))
return -EFAULT;
return 0;
}
/*
* Command control function
*
* ctrl:
* NAND_NCE: bit 0 -> bit 2
* NAND_CLE: bit 1 -> bit 7
* NAND_ALE: bit 2 -> bit 6
*/
static void ams_delta_hwcontrol(struct mtd_info *mtd, int cmd,
unsigned int ctrl)
{
if (ctrl & NAND_CTRL_CHANGE) {
unsigned long bits;
bits = (~ctrl & NAND_NCE) ? AMS_DELTA_LATCH2_NAND_NCE : 0;
bits |= (ctrl & NAND_CLE) ? AMS_DELTA_LATCH2_NAND_CLE : 0;
bits |= (ctrl & NAND_ALE) ? AMS_DELTA_LATCH2_NAND_ALE : 0;
ams_delta_latch2_write(AMS_DELTA_LATCH2_NAND_CLE |
AMS_DELTA_LATCH2_NAND_ALE |
AMS_DELTA_LATCH2_NAND_NCE, bits);
}
if (cmd != NAND_CMD_NONE)
ams_delta_write_byte(mtd, cmd);
}
static int ams_delta_nand_ready(struct mtd_info *mtd)
{
return omap_get_gpio_datain(AMS_DELTA_GPIO_PIN_NAND_RB);
}
/*
* Main initialization routine
*/
static int __init ams_delta_init(void)
{
struct nand_chip *this;
int err = 0;
/* Allocate memory for MTD device structure and private data */
ams_delta_mtd = kmalloc(sizeof(struct mtd_info) +
sizeof(struct nand_chip), GFP_KERNEL);
if (!ams_delta_mtd) {
printk (KERN_WARNING "Unable to allocate E3 NAND MTD device structure.\n");
err = -ENOMEM;
goto out;
}
ams_delta_mtd->owner = THIS_MODULE;
/* Get pointer to private data */
this = (struct nand_chip *) (&ams_delta_mtd[1]);
/* Initialize structures */
memset(ams_delta_mtd, 0, sizeof(struct mtd_info));
memset(this, 0, sizeof(struct nand_chip));
/* Link the private data with the MTD structure */
ams_delta_mtd->priv = this;
/* Set address of NAND IO lines */
this->IO_ADDR_R = (OMAP_MPUIO_BASE + OMAP_MPUIO_INPUT_LATCH);
this->IO_ADDR_W = (OMAP_MPUIO_BASE + OMAP_MPUIO_OUTPUT);
this->read_byte = ams_delta_read_byte;
this->write_buf = ams_delta_write_buf;
this->read_buf = ams_delta_read_buf;
this->verify_buf = ams_delta_verify_buf;
this->cmd_ctrl = ams_delta_hwcontrol;
if (!omap_request_gpio(AMS_DELTA_GPIO_PIN_NAND_RB)) {
this->dev_ready = ams_delta_nand_ready;
} else {
this->dev_ready = NULL;
printk(KERN_NOTICE "Couldn't request gpio for Delta NAND ready.\n");
}
/* 25 us command delay time */
this->chip_delay = 30;
this->ecc.mode = NAND_ECC_SOFT;
/* Set chip enabled, but */
ams_delta_latch2_write(NAND_MASK, AMS_DELTA_LATCH2_NAND_NRE |
AMS_DELTA_LATCH2_NAND_NWE |
AMS_DELTA_LATCH2_NAND_NCE |
AMS_DELTA_LATCH2_NAND_NWP);
/* Scan to find existance of the device */
if (nand_scan(ams_delta_mtd, 1)) {
err = -ENXIO;
goto out_mtd;
}
/* Register the partitions */
add_mtd_partitions(ams_delta_mtd, partition_info,
ARRAY_SIZE(partition_info));
goto out;
out_mtd:
kfree(ams_delta_mtd);
out:
return err;
}
module_init(ams_delta_init);
/*
* Clean up routine
*/
static void __exit ams_delta_cleanup(void)
{
/* Release resources, unregister device */
nand_release(ams_delta_mtd);
/* Free the MTD device structure */
kfree(ams_delta_mtd);
}
module_exit(ams_delta_cleanup);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Jonathan McDowell <noodles@earth.li>");
MODULE_DESCRIPTION("Glue layer for NAND flash on Amstrad E3 (Delta)");