2 * drivers/mtd/nand/at91_nand.c
4 * Copyright (C) 2003 Rick Bronson
6 * Derived from drivers/mtd/nand/autcpu12.c
7 * Copyright (c) 2001 Thomas Gleixner (gleixner@autronix.de)
9 * Derived from drivers/mtd/spia.c
10 * Copyright (C) 2000 Steven J. Hill (sjhill@cotw.com)
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License version 2 as
14 * published by the Free Software Foundation.
18 #include <linux/slab.h>
19 #include <linux/module.h>
20 #include <linux/platform_device.h>
21 #include <linux/mtd/mtd.h>
22 #include <linux/mtd/nand.h>
23 #include <linux/mtd/partitions.h>
26 #include <asm/sizes.h>
28 #include <asm/hardware.h>
29 #include <asm/arch/board.h>
30 #include <asm/arch/gpio.h>
32 struct at91_nand_host {
33 struct nand_chip nand_chip;
35 void __iomem *io_base;
36 struct at91_nand_data *board;
40 * Hardware specific access to control-lines
42 static void at91_nand_cmd_ctrl(struct mtd_info *mtd, int cmd, unsigned int ctrl)
44 struct nand_chip *nand_chip = mtd->priv;
45 struct at91_nand_host *host = nand_chip->priv;
47 if (cmd == NAND_CMD_NONE)
51 writeb(cmd, host->io_base + (1 << host->board->cle));
53 writeb(cmd, host->io_base + (1 << host->board->ale));
57 * Read the Device Ready pin.
59 static int at91_nand_device_ready(struct mtd_info *mtd)
61 struct nand_chip *nand_chip = mtd->priv;
62 struct at91_nand_host *host = nand_chip->priv;
64 return at91_get_gpio_value(host->board->rdy_pin);
70 static void at91_nand_enable(struct at91_nand_host *host)
72 if (host->board->enable_pin)
73 at91_set_gpio_value(host->board->enable_pin, 0);
79 static void at91_nand_disable(struct at91_nand_host *host)
81 if (host->board->enable_pin)
82 at91_set_gpio_value(host->board->enable_pin, 1);
86 * Probe for the NAND device.
88 static int __init at91_nand_probe(struct platform_device *pdev)
90 struct at91_nand_host *host;
92 struct nand_chip *nand_chip;
95 #ifdef CONFIG_MTD_PARTITIONS
96 struct mtd_partition *partitions = NULL;
97 int num_partitions = 0;
100 /* Allocate memory for the device structure (and zero it) */
101 host = kzalloc(sizeof(struct at91_nand_host), GFP_KERNEL);
103 printk(KERN_ERR "at91_nand: failed to allocate device structure.\n");
107 host->io_base = ioremap(pdev->resource[0].start,
108 pdev->resource[0].end - pdev->resource[0].start + 1);
109 if (host->io_base == NULL) {
110 printk(KERN_ERR "at91_nand: ioremap failed\n");
116 nand_chip = &host->nand_chip;
117 host->board = pdev->dev.platform_data;
119 nand_chip->priv = host; /* link the private data structures */
120 mtd->priv = nand_chip;
121 mtd->owner = THIS_MODULE;
123 /* Set address of NAND IO lines */
124 nand_chip->IO_ADDR_R = host->io_base;
125 nand_chip->IO_ADDR_W = host->io_base;
126 nand_chip->cmd_ctrl = at91_nand_cmd_ctrl;
127 nand_chip->dev_ready = at91_nand_device_ready;
128 nand_chip->ecc.mode = NAND_ECC_SOFT; /* enable ECC */
129 nand_chip->chip_delay = 20; /* 20us command delay time */
131 platform_set_drvdata(pdev, host);
132 at91_nand_enable(host);
134 if (host->board->det_pin) {
135 if (at91_get_gpio_value(host->board->det_pin)) {
136 printk ("No SmartMedia card inserted.\n");
142 /* Scan to find existance of the device */
143 if (nand_scan(mtd, 1)) {
148 #ifdef CONFIG_MTD_PARTITIONS
149 if (host->board->partition_info)
150 partitions = host->board->partition_info(mtd->size, &num_partitions);
152 if ((!partitions) || (num_partitions == 0)) {
153 printk(KERN_ERR "at91_nand: No parititions defined, or unsupported device.\n");
158 res = add_mtd_partitions(mtd, partitions, num_partitions);
160 res = add_mtd_device(mtd);
169 at91_nand_disable(host);
170 platform_set_drvdata(pdev, NULL);
171 iounmap(host->io_base);
177 * Remove a NAND device.
179 static int __devexit at91_nand_remove(struct platform_device *pdev)
181 struct at91_nand_host *host = platform_get_drvdata(pdev);
182 struct mtd_info *mtd = &host->mtd;
186 at91_nand_disable(host);
188 iounmap(host->io_base);
194 static struct platform_driver at91_nand_driver = {
195 .probe = at91_nand_probe,
196 .remove = at91_nand_remove,
199 .owner = THIS_MODULE,
203 static int __init at91_nand_init(void)
205 return platform_driver_register(&at91_nand_driver);
209 static void __exit at91_nand_exit(void)
211 platform_driver_unregister(&at91_nand_driver);
215 module_init(at91_nand_init);
216 module_exit(at91_nand_exit);
218 MODULE_LICENSE("GPL");
219 MODULE_AUTHOR("Rick Bronson");
220 MODULE_DESCRIPTION("NAND/SmartMedia driver for AT91RM9200");