1/*
2 *  linux/drivers/mtd/nand/cmx270-nand.c
3 *
4 *  Copyright (C) 2006 Compulab, Ltd.
5 *  Mike Rapoport <mike@compulab.co.il>
6 *
7 *  Derived from drivers/mtd/nand/h1910.c
8 *       Copyright (C) 2002 Marius Gröger (mag@sysgo.de)
9 *       Copyright (c) 2001 Thomas Gleixner (gleixner@autronix.de)
10 *
11 *
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.
15 *
16 *  Overview:
17 *   This is a device driver for the NAND flash device found on the
18 *   CM-X270 board.
19 */
20
21#include <linux/mtd/nand.h>
22#include <linux/mtd/partitions.h>
23#include <linux/slab.h>
24#include <linux/gpio.h>
25#include <linux/module.h>
26
27#include <asm/io.h>
28#include <asm/irq.h>
29#include <asm/mach-types.h>
30
31#include <mach/pxa2xx-regs.h>
32
33#define GPIO_NAND_CS	(11)
34#define GPIO_NAND_RB	(89)
35
36/* MTD structure for CM-X270 board */
37static struct mtd_info *cmx270_nand_mtd;
38
39/* remaped IO address of the device */
40static void __iomem *cmx270_nand_io;
41
42/*
43 * Define static partitions for flash device
44 */
45static struct mtd_partition partition_info[] = {
46	[0] = {
47		.name	= "cmx270-0",
48		.offset	= 0,
49		.size	= MTDPART_SIZ_FULL
50	}
51};
52#define NUM_PARTITIONS (ARRAY_SIZE(partition_info))
53
54static u_char cmx270_read_byte(struct mtd_info *mtd)
55{
56	struct nand_chip *this = mtd->priv;
57
58	return (readl(this->IO_ADDR_R) >> 16);
59}
60
61static void cmx270_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
62{
63	int i;
64	struct nand_chip *this = mtd->priv;
65
66	for (i=0; i<len; i++)
67		writel((*buf++ << 16), this->IO_ADDR_W);
68}
69
70static void cmx270_read_buf(struct mtd_info *mtd, u_char *buf, int len)
71{
72	int i;
73	struct nand_chip *this = mtd->priv;
74
75	for (i=0; i<len; i++)
76		*buf++ = readl(this->IO_ADDR_R) >> 16;
77}
78
79static inline void nand_cs_on(void)
80{
81	gpio_set_value(GPIO_NAND_CS, 0);
82}
83
84static void nand_cs_off(void)
85{
86	dsb();
87
88	gpio_set_value(GPIO_NAND_CS, 1);
89}
90
91/*
92 *	hardware specific access to control-lines
93 */
94static void cmx270_hwcontrol(struct mtd_info *mtd, int dat,
95			     unsigned int ctrl)
96{
97	struct nand_chip* this = mtd->priv;
98	unsigned int nandaddr = (unsigned int)this->IO_ADDR_W;
99
100	dsb();
101
102	if (ctrl & NAND_CTRL_CHANGE) {
103		if ( ctrl & NAND_ALE )
104			nandaddr |=  (1 << 3);
105		else
106			nandaddr &= ~(1 << 3);
107		if ( ctrl & NAND_CLE )
108			nandaddr |=  (1 << 2);
109		else
110			nandaddr &= ~(1 << 2);
111		if ( ctrl & NAND_NCE )
112			nand_cs_on();
113		else
114			nand_cs_off();
115	}
116
117	dsb();
118	this->IO_ADDR_W = (void __iomem*)nandaddr;
119	if (dat != NAND_CMD_NONE)
120		writel((dat << 16), this->IO_ADDR_W);
121
122	dsb();
123}
124
125/*
126 *	read device ready pin
127 */
128static int cmx270_device_ready(struct mtd_info *mtd)
129{
130	dsb();
131
132	return (gpio_get_value(GPIO_NAND_RB));
133}
134
135/*
136 * Main initialization routine
137 */
138static int __init cmx270_init(void)
139{
140	struct nand_chip *this;
141	int ret;
142
143	if (!(machine_is_armcore() && cpu_is_pxa27x()))
144		return -ENODEV;
145
146	ret = gpio_request(GPIO_NAND_CS, "NAND CS");
147	if (ret) {
148		pr_warning("CM-X270: failed to request NAND CS gpio\n");
149		return ret;
150	}
151
152	gpio_direction_output(GPIO_NAND_CS, 1);
153
154	ret = gpio_request(GPIO_NAND_RB, "NAND R/B");
155	if (ret) {
156		pr_warning("CM-X270: failed to request NAND R/B gpio\n");
157		goto err_gpio_request;
158	}
159
160	gpio_direction_input(GPIO_NAND_RB);
161
162	/* Allocate memory for MTD device structure and private data */
163	cmx270_nand_mtd = kzalloc(sizeof(struct mtd_info) +
164				  sizeof(struct nand_chip),
165				  GFP_KERNEL);
166	if (!cmx270_nand_mtd) {
167		ret = -ENOMEM;
168		goto err_kzalloc;
169	}
170
171	cmx270_nand_io = ioremap(PXA_CS1_PHYS, 12);
172	if (!cmx270_nand_io) {
173		pr_debug("Unable to ioremap NAND device\n");
174		ret = -EINVAL;
175		goto err_ioremap;
176	}
177
178	/* Get pointer to private data */
179	this = (struct nand_chip *)(&cmx270_nand_mtd[1]);
180
181	/* Link the private data with the MTD structure */
182	cmx270_nand_mtd->owner = THIS_MODULE;
183	cmx270_nand_mtd->priv = this;
184
185	/* insert callbacks */
186	this->IO_ADDR_R = cmx270_nand_io;
187	this->IO_ADDR_W = cmx270_nand_io;
188	this->cmd_ctrl = cmx270_hwcontrol;
189	this->dev_ready = cmx270_device_ready;
190
191	/* 15 us command delay time */
192	this->chip_delay = 20;
193	this->ecc.mode = NAND_ECC_SOFT;
194
195	/* read/write functions */
196	this->read_byte = cmx270_read_byte;
197	this->read_buf = cmx270_read_buf;
198	this->write_buf = cmx270_write_buf;
199
200	/* Scan to find existence of the device */
201	if (nand_scan (cmx270_nand_mtd, 1)) {
202		pr_notice("No NAND device\n");
203		ret = -ENXIO;
204		goto err_scan;
205	}
206
207	/* Register the partitions */
208	ret = mtd_device_parse_register(cmx270_nand_mtd, NULL, NULL,
209					partition_info, NUM_PARTITIONS);
210	if (ret)
211		goto err_scan;
212
213	/* Return happy */
214	return 0;
215
216err_scan:
217	iounmap(cmx270_nand_io);
218err_ioremap:
219	kfree(cmx270_nand_mtd);
220err_kzalloc:
221	gpio_free(GPIO_NAND_RB);
222err_gpio_request:
223	gpio_free(GPIO_NAND_CS);
224
225	return ret;
226
227}
228module_init(cmx270_init);
229
230/*
231 * Clean up routine
232 */
233static void __exit cmx270_cleanup(void)
234{
235	/* Release resources, unregister device */
236	nand_release(cmx270_nand_mtd);
237
238	gpio_free(GPIO_NAND_RB);
239	gpio_free(GPIO_NAND_CS);
240
241	iounmap(cmx270_nand_io);
242
243	/* Free the MTD device structure */
244	kfree (cmx270_nand_mtd);
245}
246module_exit(cmx270_cleanup);
247
248MODULE_LICENSE("GPL");
249MODULE_AUTHOR("Mike Rapoport <mike@compulab.co.il>");
250MODULE_DESCRIPTION("NAND flash driver for Compulab CM-X270 Module");
251