summaryrefslogtreecommitdiffstats
path: root/drivers/mtd/nand/cmx270_nand.c
blob: fc8529bedfdf2076b6cc17b402d660d2d0d7d856 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
/*
 *  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/gpio.h>

#include <asm/io.h>
#include <asm/irq.h>
#include <asm/mach-types.h>

#include <asm/arch/hardware.h>
#include <asm/arch/pxa-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))

const char *part_probes[] = { "cmdlinepart", NULL };

static u_char cmx270_read_byte(struct mtd_info *mtd)
{
	struct nand_chip *this = mtd->priv;

	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->priv;

	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->priv;

	for (i=0; i<len; i++)
		*buf++ = readl(this->IO_ADDR_R) >> 16;
}

static int cmx270_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) >> 16))
			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 cmx270_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 << 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 cmx270_init(void)
{
	struct nand_chip *this;
	const char *part_type;
	struct mtd_partition *mtd_parts;
	int mtd_parts_nb = 0;
	int ret;

	if (!machine_is_armcore())
		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 */
	cmx270_nand_mtd = kzalloc(sizeof(struct mtd_info) +
				  sizeof(struct nand_chip),
				  GFP_KERNEL);
	if (!cmx270_nand_mtd) {
		pr_debug("Unable to allocate CM-X270 NAND MTD device structure.\n");
		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;
	}

	/* Get pointer to private data */
	this = (struct nand_chip *)(&cmx270_nand_mtd[1]);

	/* Link the private data with the MTD structure */
	cmx270_nand_mtd->owner = THIS_MODULE;
	cmx270_nand_mtd->priv = this;

	/* 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;

	/* read/write functions */
	this->read_byte = cmx270_read_byte;
	this->read_buf = cmx270_read_buf;
	this->write_buf = cmx270_write_buf;
	this->verify_buf = cmx270_verify_buf;

	/* Scan to find existence of the device */
	if (nand_scan (cmx270_nand_mtd, 1)) {
		pr_notice("No NAND device\n");
		ret = -ENXIO;
		goto err_scan;
	}

#ifdef CONFIG_MTD_CMDLINE_PARTS
	mtd_parts_nb = parse_mtd_partitions(cmx270_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 */
	pr_notice("Using %s partition definition\n", part_type);
	ret = add_mtd_partitions(cmx270_nand_mtd, mtd_parts, mtd_parts_nb);
	if (ret)
		goto err_scan;

	/* Return happy */
	return 0;

err_scan:
	iounmap(cmx270_nand_io);
err_ioremap:
	kfree(cmx270_nand_mtd);
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 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);

	/* Free the MTD device structure */
	kfree (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");