summaryrefslogtreecommitdiff
path: root/drivers/mtd/maps/latch-addr-flash.c
blob: 6dc97aa667dc553cc44033b34394374b3c8b36d1 (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
/*
 * Interface for NOR flash driver whose high address lines are latched
 *
 * Copyright © 2000 Nicolas Pitre <nico@cam.org>
 * Copyright © 2005-2008 Analog Devices Inc.
 * Copyright © 2008 MontaVista Software, Inc. <source@mvista.com>
 *
 * This file is licensed under the terms of the GNU General Public License
 * version 2. This program is licensed "as is" without any warranty of any
 * kind, whether express or implied.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/map.h>
#include <linux/mtd/partitions.h>
#include <linux/platform_device.h>
#include <linux/mtd/latch-addr-flash.h>
#include <linux/slab.h>

#define DRIVER_NAME "latch-addr-flash"

struct latch_addr_flash_info {
	struct mtd_info		*mtd;
	struct map_info		map;
	struct resource		*res;

	void			(*set_window)(unsigned long offset, void *data);
	void			*data;

	/* cache; could be found out of res */
	unsigned long		win_mask;

	spinlock_t		lock;
};

static map_word lf_read(struct map_info *map, unsigned long ofs)
{
	struct latch_addr_flash_info *info;
	map_word datum;

	info = (struct latch_addr_flash_info *)map->map_priv_1;

	spin_lock(&info->lock);

	info->set_window(ofs, info->data);
	datum = inline_map_read(map, info->win_mask & ofs);

	spin_unlock(&info->lock);

	return datum;
}

static void lf_write(struct map_info *map, map_word datum, unsigned long ofs)
{
	struct latch_addr_flash_info *info;

	info = (struct latch_addr_flash_info *)map->map_priv_1;

	spin_lock(&info->lock);

	info->set_window(ofs, info->data);
	inline_map_write(map, datum, info->win_mask & ofs);

	spin_unlock(&info->lock);
}

static void lf_copy_from(struct map_info *map, void *to,
		unsigned long from, ssize_t len)
{
	struct latch_addr_flash_info *info =
		(struct latch_addr_flash_info *) map->map_priv_1;
	unsigned n;

	while (len > 0) {
		n = info->win_mask + 1 - (from & info->win_mask);
		if (n > len)
			n = len;

		spin_lock(&info->lock);

		info->set_window(from, info->data);
		memcpy_fromio(to, map->virt + (from & info->win_mask), n);

		spin_unlock(&info->lock);

		to += n;
		from += n;
		len -= n;
	}
}

static char *rom_probe_types[] = { "cfi_probe", NULL };

static int latch_addr_flash_remove(struct platform_device *dev)
{
	struct latch_addr_flash_info *info;
	struct latch_addr_flash_data *latch_addr_data;

	info = platform_get_drvdata(dev);
	if (info == NULL)
		return 0;

	latch_addr_data = dev_get_platdata(&dev->dev);

	if (info->mtd != NULL) {
		mtd_device_unregister(info->mtd);
		map_destroy(info->mtd);
	}

	if (info->map.virt != NULL)
		iounmap(info->map.virt);

	if (info->res != NULL)
		release_mem_region(info->res->start, resource_size(info->res));

	kfree(info);

	if (latch_addr_data->done)
		latch_addr_data->done(latch_addr_data->data);

	return 0;
}

static int latch_addr_flash_probe(struct platform_device *dev)
{
	struct latch_addr_flash_data *latch_addr_data;
	struct latch_addr_flash_info *info;
	resource_size_t win_base = dev->resource->start;
	resource_size_t win_size = resource_size(dev->resource);
	char **probe_type;
	int chipsel;
	int err;

	latch_addr_data = dev_get_platdata(&dev->dev);
	if (latch_addr_data == NULL)
		return -ENODEV;

	pr_notice("latch-addr platform flash device: %#llx byte "
		  "window at %#.8llx\n",
		  (unsigned long long)win_size, (unsigned long long)win_base);

	chipsel = dev->id;

	if (latch_addr_data->init) {
		err = latch_addr_data->init(latch_addr_data->data, chipsel);
		if (err != 0)
			return err;
	}

	info = kzalloc(sizeof(struct latch_addr_flash_info), GFP_KERNEL);
	if (info == NULL) {
		err = -ENOMEM;
		goto done;
	}

	platform_set_drvdata(dev, info);

	info->res = request_mem_region(win_base, win_size, DRIVER_NAME);
	if (info->res == NULL) {
		dev_err(&dev->dev, "Could not reserve memory region\n");
		err = -EBUSY;
		goto free_info;
	}

	info->map.name		= DRIVER_NAME;
	info->map.size		= latch_addr_data->size;
	info->map.bankwidth	= latch_addr_data->width;

	info->map.phys		= NO_XIP;
	info->map.virt		= ioremap(win_base, win_size);
	if (!info->map.virt) {
		err = -ENOMEM;
		goto free_res;
	}

	info->map.map_priv_1	= (unsigned long)info;

	info->map.read		= lf_read;
	info->map.copy_from	= lf_copy_from;
	info->map.write		= lf_write;
	info->set_window	= latch_addr_data->set_window;
	info->data		= latch_addr_data->data;
	info->win_mask		= win_size - 1;

	spin_lock_init(&info->lock);

	for (probe_type = rom_probe_types; !info->mtd && *probe_type;
		probe_type++)
		info->mtd = do_map_probe(*probe_type, &info->map);

	if (info->mtd == NULL) {
		dev_err(&dev->dev, "map_probe failed\n");
		err = -ENODEV;
		goto iounmap;
	}
	info->mtd->dev.parent = &dev->dev;

	mtd_device_parse_register(info->mtd, NULL, NULL,
				  latch_addr_data->parts,
				  latch_addr_data->nr_parts);
	return 0;

iounmap:
	iounmap(info->map.virt);
free_res:
	release_mem_region(info->res->start, resource_size(info->res));
free_info:
	kfree(info);
done:
	if (latch_addr_data->done)
		latch_addr_data->done(latch_addr_data->data);
	return err;
}

static struct platform_driver latch_addr_flash_driver = {
	.probe		= latch_addr_flash_probe,
	.remove		= latch_addr_flash_remove,
	.driver		= {
		.name	= DRIVER_NAME,
	},
};

module_platform_driver(latch_addr_flash_driver);

MODULE_AUTHOR("David Griego <dgriego@mvista.com>");
MODULE_DESCRIPTION("MTD map driver for flashes addressed physically with upper "
		"address lines being set board specifically");
MODULE_LICENSE("GPL v2");