/*
* NAND flash driver for the MikroTik RouterBoard 4xx series
*
* Copyright (C) 2008-2011 Gabor Juhos <juhosg@openwrt.org>
* Copyright (C) 2008 Imre Kaloz <kaloz@openwrt.org>
*
* This file was based on the driver for Linux 2.6.22 published by
* MikroTik for their RouterBoard 4xx series devices.
*
* 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.
*/
#include <linux/init.h>
#include <linux/mtd/nand.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/partitions.h>
#include <linux/platform_device.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/gpio.h>
#include <linux/slab.h>
#include <asm/mach-ar71xx/ar71xx.h>
#include <asm/mach-ar71xx/rb4xx_cpld.h>
#define DRV_NAME "rb4xx-nand"
#define DRV_VERSION "0.2.0"
#define DRV_DESC "NAND flash driver for RouterBoard 4xx series"
#define RB4XX_NAND_GPIO_READY 5
#define RB4XX_NAND_GPIO_ALE 37
#define RB4XX_NAND_GPIO_CLE 38
#define RB4XX_NAND_GPIO_NCE 39
struct rb4xx_nand_info {
struct nand_chip chip;
struct mtd_info mtd;
};
/*
* We need to use the OLD Yaffs-1 OOB layout, otherwise the RB bootloader
* will not be able to find the kernel that we load.
*/
static struct nand_ecclayout rb4xx_nand_ecclayout = {
.eccbytes = 6,
.eccpos = { 8, 9, 10, 13, 14, 15 },
.oobavail = 9,
.oobfree = { { 0, 4 }, { 6, 2 }, { 11, 2 }, { 4, 1 } }
};
static struct mtd_partition rb4xx_nand_partitions[] = {
{
.name = "booter",
.offset = 0,
.size = (256 * 1024),
.mask_flags = MTD_WRITEABLE,
},
{
.name = "kernel",
.offset = (256 * 1024),
.size = (6 * 1024 * 1024) - (256 * 1024),
},
{
.name = "rootfs",
.offset = MTDPART_OFS_NXTBLK,
.size = MTDPART_SIZ_FULL,
},
};
static int rb4xx_nand_dev_ready(struct mtd_info *mtd)
{
return gpio_get_value_cansleep(RB4XX_NAND_GPIO_READY);
}
static void rb4xx_nand_write_cmd(unsigned char cmd)
{
unsigned char data = cmd;
int err;
err = rb4xx_cpld_write(&data, 1);
if (err)
pr_err("rb4xx_nand: write cmd failed, err=%d\n", err);
}
static void rb4xx_nand_cmd_ctrl(struct mtd_info *mtd, int cmd,
unsigned int ctrl)
{
if (ctrl & NAND_CTRL_CHANGE) {
gpio_set_value_cansleep(RB4XX_NAND_GPIO_CLE,
(ctrl & NAND_CLE) ? 1 : 0);
gpio_set_value_cansleep(RB4XX_NAND_GPIO_ALE,
(ctrl & NAND_ALE) ? 1 : 0);
gpio_set_value_cansleep(RB4XX_NAND_GPIO_NCE,
(ctrl & NAND_NCE) ? 0 : 1);
}
if (cmd != NAND_CMD_NONE)
rb4xx_nand_write_cmd(cmd);
}
static unsigned char rb4xx_nand_read_byte(struct mtd_info *mtd)
{
unsigned char data = 0;
int err;
err = rb4xx_cpld_read(&data, NULL, 1);
if (err) {
pr_err("rb4xx_nand: read data failed, err=%d\n", err);
data = 0xff;
}
return data;
}
static void rb4xx_nand_write_buf(struct mtd_info *mtd, const unsigned char *buf,
int len)
{
int err;
err = rb4xx_cpld_write(buf, len);
if (err)
pr_err("rb4xx_nand: write buf failed, err=%d\n", err);
}
static void rb4xx_nand_read_buf(struct mtd_info *mtd, unsigned char *buf,
int len)
{
int err;
err = rb4xx_cpld_read(buf, NULL, len);
if (err)
pr_err("rb4xx_nand: read buf failed, err=%d\n", err);
}
static int __init rb4xx_nand_probe(struct platform_device *pdev)
{
struct rb4xx_nand_info *info;
int ret;
printk(KERN_INFO DRV_DESC " version " DRV_VERSION "\n");
ret = gpio_request(RB4XX_NAND_GPIO_READY, "NAND RDY");
if (ret) {
dev_err(&pdev->dev, "unable to request gpio %d\n",
RB4XX_NAND_GPIO_READY);
goto err;
}
ret = gpio_direction_input(RB4XX_NAND_GPIO_READY);
if (ret) {
dev_err(&pdev->dev, "unable to set input mode on gpio %d\n",
RB4XX_NAND_GPIO_READY);
goto err_free_gpio_ready;
}
ret = gpio_request(RB4XX_NAND_GPIO_ALE, "NAND ALE");
if (ret) {
dev_err(&pdev->dev, "unable to request gpio %d\n",
RB4XX_NAND_GPIO_ALE);
goto err_free_gpio_ready;
}
ret = gpio_direction_output(RB4XX_NAND_GPIO_ALE, 0);
if (ret) {
dev_err(&pdev->dev, "unable to set output mode on gpio %d\n",
RB4XX_NAND_GPIO_ALE);
goto err_free_gpio_ale;
}
ret = gpio_request(RB4XX_NAND_GPIO_CLE, "NAND CLE");
if (ret) {
dev_err(&pdev->dev, "unable to request gpio %d\n",
RB4XX_NAND_GPIO_CLE);
goto err_free_gpio_ale;
}
ret = gpio_direction_output(RB4XX_NAND_GPIO_CLE, 0);
if (ret) {
dev_err(&pdev->dev, "unable to set output mode on gpio %d\n",
RB4XX_NAND_GPIO_CLE);
goto err_free_gpio_cle;
}
ret = gpio_request(RB4XX_NAND_GPIO_NCE, "NAND NCE");
if (ret) {
dev_err(&pdev->dev, "unable to request gpio %d\n",
RB4XX_NAND_GPIO_NCE);
goto err_free_gpio_cle;
}
ret = gpio_direction_output(RB4XX_NAND_GPIO_NCE, 1);
if (ret) {
dev_err(&pdev->dev, "unable to set output mode on gpio %d\n",
RB4XX_NAND_GPIO_ALE);
goto err_free_gpio_nce;
}
info = kzalloc(sizeof(*info), GFP_KERNEL);
if (!info) {
dev_err(&pdev->dev, "rb4xx-nand: no memory for private data\n");
ret = -ENOMEM;
goto err_free_gpio_nce;
}
info->chip.priv = &info;
info->mtd.priv = &info->chip;
info->mtd.owner = THIS_MODULE;
info->chip.cmd_ctrl = rb4xx_nand_cmd_ctrl;
info->chip.dev_ready = rb4xx_nand_dev_ready;
info->chip.read_byte = rb4xx_nand_read_byte;
info->chip.write_buf = rb4xx_nand_write_buf;
info->chip.read_buf = rb4xx_nand_read_buf;
#if 0
info->chip.verify_buf = rb4xx_nand_verify_buf;
#endif
info->chip.chip_delay = 25;
info->chip.ecc.mode = NAND_ECC_SOFT;
info->chip.options |= NAND_NO_AUTOINCR;
platform_set_drvdata(pdev, info);
ret = nand_scan_ident(&info->mtd, 1);
if (ret) {
ret = -ENXIO;
goto err_free_info;
}
if (info->mtd.writesize == 512)
info->chip.ecc.layout = &rb4xx_nand_ecclayout;
ret = nand_scan_tail(&info->mtd);
if (ret) {
return -ENXIO;
goto err_set_drvdata;
}
#ifdef CONFIG_MTD_PARTITIONS
ret = add_mtd_partitions(&info->mtd, rb4xx_nand_partitions,
ARRAY_SIZE(rb4xx_nand_partitions));
#else
ret = add_mtd_device(&info->mtd);
#endif
if (ret)
goto err_release_nand;
return 0;
err_release_nand:
nand_release(&info->mtd);
err_set_drvdata:
platform_set_drvdata(pdev, NULL);
err_free_info:
kfree(info);
err_free_gpio_nce:
gpio_free(RB4XX_NAND_GPIO_NCE);
err_free_gpio_cle:
gpio_free(RB4XX_NAND_GPIO_CLE);
err_free_gpio_ale:
gpio_free(RB4XX_NAND_GPIO_ALE);
err_free_gpio_ready:
gpio_free(RB4XX_NAND_GPIO_READY);
err:
return ret;
}
static int __devexit rb4xx_nand_remove(struct platform_device *pdev)
{
struct rb4xx_nand_info *info = platform_get_drvdata(pdev);
nand_release(&info->mtd);
platform_set_drvdata(pdev, NULL);
kfree(info);
gpio_free(RB4XX_NAND_GPIO_NCE);
gpio_free(RB4XX_NAND_GPIO_CLE);
gpio_free(RB4XX_NAND_GPIO_ALE);
gpio_free(RB4XX_NAND_GPIO_READY);
return 0;
}
static struct platform_driver rb4xx_nand_driver = {
.probe = rb4xx_nand_probe,
.remove = __devexit_p(rb4xx_nand_remove),
.driver = {
.name = DRV_NAME,
.owner = THIS_MODULE,
},
};
static int __init rb4xx_nand_init(void)
{
return platform_driver_register(&rb4xx_nand_driver);
}
static void __exit rb4xx_nand_exit(void)
{
platform_driver_unregister(&rb4xx_nand_driver);
}
module_init(rb4xx_nand_init);
module_exit(rb4xx_nand_exit);
MODULE_DESCRIPTION(DRV_DESC);
MODULE_VERSION(DRV_VERSION);
MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");
MODULE_AUTHOR("Imre Kaloz <kaloz@openwrt.org>");
MODULE_LICENSE("GPL v2");