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/*
* linux/drivers/mtd/nand/cmx270-nand.c
*
* Copyright (C) 2006 Compulab, Ltd.
* Mike Rapoport <mike@compulab.co.il>
*
* Derived from drivers/mtd/nand/h1910.c
* Copyright (C) 2002 Marius Gröger (mag@sysgo.de)
* Copyright (c) 2001 Thomas Gleixner (gleixner@autronix.de)
*
*
* 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
* CM-X270 board.
*/
#include <linux/mtd/nand.h>
#include <linux/mtd/partitions.h>
#include <linux/slab.h>
#include <linux/gpio.h>
#include <linux/module.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/mach-types.h>
#include <mach/pxa2xx-regs.h>
#define GPIO_NAND_CS (11)
#define GPIO_NAND_RB (89)
/* MTD structure for CM-X270 board */
static struct mtd_info *cmx270_nand_mtd;
/* remaped IO address of the device */
static void __iomem *cmx270_nand_io;
/*
* Define static partitions for flash device
*/
static struct mtd_partition partition_info[] = {
[0] = {
.name = "cmx270-0",
.offset = 0,
.size = MTDPART_SIZ_FULL
}
};
#define NUM_PARTITIONS (ARRAY_SIZE(partition_info))
static u_char cmx270_read_byte(struct mtd_info *mtd)
{
struct nand_chip *this = mtd_to_nand(mtd);
return (readl(this->IO_ADDR_R) >> 16);
}
static void cmx270_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
{
int i;
struct nand_chip *this = mtd_to_nand(mtd);
for (i=0; i<len; i++)
writel((*buf++ << 16), this->IO_ADDR_W);
}
static void cmx270_read_buf(struct mtd_info *mtd, u_char *buf, int len)
{
int i;
struct nand_chip *this = mtd_to_nand(mtd);
for (i=0; i<len; i++)
*buf++ = readl(this->IO_ADDR_R) >> 16;
}
static inline void nand_cs_on(void)
{
gpio_set_value(GPIO_NAND_CS, 0);
}
static void nand_cs_off(void)
{
dsb();
gpio_set_value(GPIO_NAND_CS, 1);
}
/*
* hardware specific access to control-lines
*/
static void cmx270_hwcontrol(struct mtd_info *mtd, int dat,
unsigned int ctrl)
{
struct nand_chip *this = mtd_to_nand(mtd);
unsigned int nandaddr = (unsigned int)this->IO_ADDR_W;
dsb();
if (ctrl & NAND_CTRL_CHANGE) {
if ( ctrl & NAND_ALE )
nandaddr |= (1 << 3);
else
nandaddr &= ~(1 << 3);
if ( ctrl & NAND_CLE )
nandaddr |= (1 << 2);
else
nandaddr &= ~(1 << 2);
if ( ctrl & NAND_NCE )
nand_cs_on();
else
nand_cs_off();
}
dsb();
this->IO_ADDR_W = (void __iomem*)nandaddr;
if (dat != NAND_CMD_NONE)
writel((dat << 16), this->IO_ADDR_W);
dsb();
}
/*
* read device ready pin
*/
static int cmx270_device_ready(struct mtd_info *mtd)
{
dsb();
return (gpio_get_value(GPIO_NAND_RB));
}
/*
* Main initialization routine
*/
static int __init cmx270_init(void)
{
struct nand_chip *this;
int ret;
if (!(machine_is_armcore() && cpu_is_pxa27x()))
return -ENODEV;
ret = gpio_request(GPIO_NAND_CS, "NAND CS");
if (ret) {
pr_warning("CM-X270: failed to request NAND CS gpio\n");
return ret;
}
gpio_direction_output(GPIO_NAND_CS, 1);
ret = gpio_request(GPIO_NAND_RB, "NAND R/B");
if (ret) {
pr_warning("CM-X270: failed to request NAND R/B gpio\n");
goto err_gpio_request;
}
gpio_direction_input(GPIO_NAND_RB);
/* Allocate memory for MTD device structure and private data */
this = kzalloc(sizeof(struct nand_chip), GFP_KERNEL);
if (!this) {
ret = -ENOMEM;
goto err_kzalloc;
}
cmx270_nand_io = ioremap(PXA_CS1_PHYS, 12);
if (!cmx270_nand_io) {
pr_debug("Unable to ioremap NAND device\n");
ret = -EINVAL;
goto err_ioremap;
}
cmx270_nand_mtd = nand_to_mtd(this);
/* Link the private data with the MTD structure */
cmx270_nand_mtd->owner = THIS_MODULE;
/* insert callbacks */
this->IO_ADDR_R = cmx270_nand_io;
this->IO_ADDR_W = cmx270_nand_io;
this->cmd_ctrl = cmx270_hwcontrol;
this->dev_ready = cmx270_device_ready;
/* 15 us command delay time */
this->chip_delay = 20;
this->ecc.mode = NAND_ECC_SOFT;
this->ecc.algo = NAND_ECC_HAMMING;
/* read/write functions */
this->read_byte = cmx270_read_byte;
this->read_buf = cmx270_read_buf;
this->write_buf = cmx270_write_buf;
/* Scan to find existence of the device */
ret = nand_scan(cmx270_nand_mtd, 1);
if (ret) {
pr_notice("No NAND device\n");
goto err_scan;
}
/* Register the partitions */
ret = mtd_device_parse_register(cmx270_nand_mtd, NULL, NULL,
partition_info, NUM_PARTITIONS);
if (ret)
goto err_scan;
/* Return happy */
return 0;
err_scan:
iounmap(cmx270_nand_io);
err_ioremap:
kfree(this);
err_kzalloc:
gpio_free(GPIO_NAND_RB);
err_gpio_request:
gpio_free(GPIO_NAND_CS);
return ret;
}
module_init(cmx270_init);
/*
* Clean up routine
*/
static void __exit cmx270_cleanup(void)
{
/* Release resources, unregister device */
nand_release(cmx270_nand_mtd);
gpio_free(GPIO_NAND_RB);
gpio_free(GPIO_NAND_CS);
iounmap(cmx270_nand_io);
kfree(mtd_to_nand(cmx270_nand_mtd));
}
module_exit(cmx270_cleanup);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Mike Rapoport <mike@compulab.co.il>");
MODULE_DESCRIPTION("NAND flash driver for Compulab CM-X270 Module");
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