android_kernel_xiaomi_sm8350/drivers/mtd/nand/edb7312.c
Thomas Gleixner 7abd3ef987 [MTD] Refactor NAND hwcontrol to cmd_ctrl
The hwcontrol function enforced a step by step state machine
for any kind of hardware chip access. Let the hardware driver
know which control bits are set and inform it about a change
of the control lines. Let the hardware driver write out the
command and address bytes directly. This gives a peformance
advantage for address bus controlled chips and simplifies the
quirks in the hardware drivers.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2006-05-23 23:25:53 +02:00

213 lines
5.1 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 7
* 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;
bits = (ctrl & (NAND_CLE | NAND_ALE)) << 3;
bits = (ctrl & NAND_NCE) << 7;
clps_writeb((clps_readb(ep7312_pxdr) & 0xB0) | 0x10,
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);
/* Free internal data buffer */
kfree(this->data_buf);
/* 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");