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#include <linux/mtd/nand.h>
#include <linux/mtd/partitions.h>
#include <asm/arch/gpio.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/arch/hardware.h>
#include <asm/arch/pxa-regs.h>
#include <asm/mach-types.h>
#define GPIO_NAND_CS (82)
#define GPIO_NAND_RB (83)
/* MTD structure for CM-X270 board */
static struct mtd_info *up270_nand_mtd;
/* remaped IO address of the device */
static void __iomem *up270_nand_io;
/*
* Define static partitions for flash device
*/
static struct mtd_partition partition_info[] = {
[0] = {
.name = "UP270-nand",
.offset = 0,
.size = 0x4000000,
}
};
#define NUM_PARTITIONS (ARRAY_SIZE(partition_info))
const char *part_probes[] = { "cmdlinepart", NULL };
static u_char up270_read_byte(struct mtd_info *mtd)
{
struct nand_chip *this = mtd->priv;
return readl(this->IO_ADDR_R);
}
static void up270_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
{
int i;
struct nand_chip *this = mtd->priv;
for (i=0; i<len; i++)
writel(*buf++, this->IO_ADDR_W);
}
static void up270_read_buf(struct mtd_info *mtd, u_char *buf, int len)
{
int i;
struct nand_chip *this = mtd->priv;
for (i=0; i<len; i++)
*buf++ = readl(this->IO_ADDR_R);
}
static int up270_verify_buf(struct mtd_info *mtd, const u_char *buf, int len)
{
int i;
struct nand_chip *this = mtd->priv;
for (i=0; i<len; i++)
if (buf[i] != (u_char)(readl(this->IO_ADDR_R)))
return -EFAULT;
return 0;
}
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 up270_hwcontrol(struct mtd_info *mtd, int dat,
unsigned int ctrl)
{
struct nand_chip* this = mtd->priv;
unsigned int nandaddr = (unsigned int)this->IO_ADDR_W;
dsb();
if (ctrl & NAND_CTRL_CHANGE) {
if ( ctrl & NAND_ALE )
nandaddr |= (1 << 2);
else
nandaddr &= ~(1 << 2);
if ( ctrl & NAND_CLE )
nandaddr |= (1 << 3);
else
nandaddr &= ~(1 << 3);
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, this->IO_ADDR_W);
dsb();
}
/*
* read device ready pin
*/
static int up270_device_ready(struct mtd_info *mtd)
{
dsb();
return (gpio_get_value(GPIO_NAND_RB));
}
/*
* Main initialization routine
*/
static int up270_init(void)
{
struct nand_chip *this;
const char *part_type;
struct mtd_partition *mtd_parts;
int mtd_parts_nb = 0;
int ret;
ret = gpio_request(GPIO_NAND_CS, "NAND CS");
if (ret) {
printk("UP270: 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) {
printk("UP270: 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 */
up270_nand_mtd = kzalloc(sizeof(struct mtd_info) +
sizeof(struct nand_chip),
GFP_KERNEL);
if (!up270_nand_mtd) {
printk("Unable to allocate UP270 NAND MTD device structure.\n");
ret = -ENOMEM;
goto err_kzalloc;
}
up270_nand_io = ioremap(0x04000000, 12);
if (!up270_nand_io) {
printk("Unable to ioremap NAND device\n");
ret = -EINVAL;
goto err_ioremap;
}
/* Get pointer to private data */
this = (struct nand_chip *)(&up270_nand_mtd[1]);
/* Link the private data with the MTD structure */
up270_nand_mtd->owner = THIS_MODULE;
up270_nand_mtd->priv = this;
/* insert callbacks */
this->IO_ADDR_R = up270_nand_io;
this->IO_ADDR_W = up270_nand_io;
this->cmd_ctrl = up270_hwcontrol;
this->dev_ready = up270_device_ready;
/* 15 us command delay time */
this->chip_delay = 20;
this->ecc.mode = NAND_ECC_SOFT;
/* read/write functions */
this->read_byte = up270_read_byte;
this->read_buf = up270_read_buf;
this->write_buf = up270_write_buf;
this->verify_buf = up270_verify_buf;
/* Scan to find existence of the device */
if (nand_scan (up270_nand_mtd, 1)) {
printk(KERN_NOTICE "No NAND device\n");
ret = -ENXIO;
goto err_scan;
}
#ifdef CONFIG_MTD_CMDLINE_PARTS
mtd_parts_nb = parse_mtd_partitions(up270_nand_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) {
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);
ret = add_mtd_partitions(up270_nand_mtd, mtd_parts, mtd_parts_nb);
if (ret)
goto err_scan;
/* Return happy */
return 0;
err_scan:
iounmap(up270_nand_io);
err_ioremap:
kfree(up270_nand_mtd);
err_kzalloc:
gpio_free(GPIO_NAND_RB);
err_gpio_request:
gpio_free(GPIO_NAND_CS);
return ret;
}
module_init(up270_init);
/*
* Clean up routine
*/
static void up270_cleanup(void)
{
/* Release resources, unregister device */
nand_release(up270_nand_mtd);
gpio_free(GPIO_NAND_RB);
gpio_free(GPIO_NAND_CS);
iounmap(up270_nand_io);
/* Free the MTD device structure */
kfree (up270_nand_mtd);
}
module_exit(up270_cleanup);
MODULE_LICENSE("GPL");
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