summaryrefslogtreecommitdiffstats
path: root/drivers/ssb/sprom.c
blob: a3b23644b0fbb42218285c571656a8db2154517d (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
/*
 * Sonics Silicon Backplane
 * Common SPROM support routines
 *
 * Copyright (C) 2005-2008 Michael Buesch <m@bues.ch>
 * Copyright (C) 2005 Martin Langer <martin-langer@gmx.de>
 * Copyright (C) 2005 Stefano Brivio <st3@riseup.net>
 * Copyright (C) 2005 Danny van Dyk <kugelfang@gentoo.org>
 * Copyright (C) 2005 Andreas Jaggi <andreas.jaggi@waterwave.ch>
 *
 * Licensed under the GNU/GPL. See COPYING for details.
 */

#include "ssb_private.h"

#include <linux/ctype.h>
#include <linux/slab.h>


static int(*get_fallback_sprom)(struct ssb_bus *dev, struct ssb_sprom *out);


static int sprom2hex(const u16 *sprom, char *buf, size_t buf_len,
		     size_t sprom_size_words)
{
	int i, pos = 0;

	for (i = 0; i < sprom_size_words; i++)
		pos += snprintf(buf + pos, buf_len - pos - 1,
				"%04X", swab16(sprom[i]) & 0xFFFF);
	pos += snprintf(buf + pos, buf_len - pos - 1, "\n");

	return pos + 1;
}

static int hex2sprom(u16 *sprom, const char *dump, size_t len,
		     size_t sprom_size_words)
{
	char c, tmp[5] = { 0 };
	int err, cnt = 0;
	unsigned long parsed;

	/* Strip whitespace at the end. */
	while (len) {
		c = dump[len - 1];
		if (!isspace(c) && c != '\0')
			break;
		len--;
	}
	/* Length must match exactly. */
	if (len != sprom_size_words * 4)
		return -EINVAL;

	while (cnt < sprom_size_words) {
		memcpy(tmp, dump, 4);
		dump += 4;
		err = strict_strtoul(tmp, 16, &parsed);
		if (err)
			return err;
		sprom[cnt++] = swab16((u16)parsed);
	}

	return 0;
}

/* Common sprom device-attribute show-handler */
ssize_t ssb_attr_sprom_show(struct ssb_bus *bus, char *buf,
			    int (*sprom_read)(struct ssb_bus *bus, u16 *sprom))
{
	u16 *sprom;
	int err = -ENOMEM;
	ssize_t count = 0;
	size_t sprom_size_words = bus->sprom_size;

	sprom = kcalloc(sprom_size_words, sizeof(u16), GFP_KERNEL);
	if (!sprom)
		goto out;

	/* Use interruptible locking, as the SPROM write might
	 * be holding the lock for several seconds. So allow userspace
	 * to cancel operation. */
	err = -ERESTARTSYS;
	if (mutex_lock_interruptible(&bus->sprom_mutex))
		goto out_kfree;
	err = sprom_read(bus, sprom);
	mutex_unlock(&bus->sprom_mutex);

	if (!err)
		count = sprom2hex(sprom, buf, PAGE_SIZE, sprom_size_words);

out_kfree:
	kfree(sprom);
out:
	return err ? err : count;
}

/* Common sprom device-attribute store-handler */
ssize_t ssb_attr_sprom_store(struct ssb_bus *bus,
			     const char *buf, size_t count,
			     int (*sprom_check_crc)(const u16 *sprom, size_t size),
			     int (*sprom_write)(struct ssb_bus *bus, const u16 *sprom))
{
	u16 *sprom;
	int res = 0, err = -ENOMEM;
	size_t sprom_size_words = bus->sprom_size;
	struct ssb_freeze_context freeze;

	sprom = kcalloc(bus->sprom_size, sizeof(u16), GFP_KERNEL);
	if (!sprom)
		goto out;
	err = hex2sprom(sprom, buf, count, sprom_size_words);
	if (err) {
		err = -EINVAL;
		goto out_kfree;
	}
	err = sprom_check_crc(sprom, sprom_size_words);
	if (err) {
		err = -EINVAL;
		goto out_kfree;
	}

	/* Use interruptible locking, as the SPROM write might
	 * be holding the lock for several seconds. So allow userspace
	 * to cancel operation. */
	err = -ERESTARTSYS;
	if (mutex_lock_interruptible(&bus->sprom_mutex))
		goto out_kfree;
	err = ssb_devices_freeze(bus, &freeze);
	if (err) {
		ssb_err("SPROM write: Could not freeze all devices\n");
		goto out_unlock;
	}
	res = sprom_write(bus, sprom);
	err = ssb_devices_thaw(&freeze);
	if (err)
		ssb_err("SPROM write: Could not thaw all devices\n");
out_unlock:
	mutex_unlock(&bus->sprom_mutex);
out_kfree:
	kfree(sprom);
out:
	if (res)
		return res;
	return err ? err : count;
}

/**
 * ssb_arch_register_fallback_sprom - Registers a method providing a
 * fallback SPROM if no SPROM is found.
 *
 * @sprom_callback: The callback function.
 *
 * With this function the architecture implementation may register a
 * callback handler which fills the SPROM data structure. The fallback is
 * only used for PCI based SSB devices, where no valid SPROM can be found
 * in the shadow registers.
 *
 * This function is useful for weird architectures that have a half-assed
 * SSB device hardwired to their PCI bus.
 *
 * Note that it does only work with PCI attached SSB devices. PCMCIA
 * devices currently don't use this fallback.
 * Architectures must provide the SPROM for native SSB devices anyway, so
 * the fallback also isn't used for native devices.
 *
 * This function is available for architecture code, only. So it is not
 * exported.
 */
int ssb_arch_register_fallback_sprom(int (*sprom_callback)(struct ssb_bus *bus,
				     struct ssb_sprom *out))
{
	if (get_fallback_sprom)
		return -EEXIST;
	get_fallback_sprom = sprom_callback;

	return 0;
}

int ssb_fill_sprom_with_fallback(struct ssb_bus *bus, struct ssb_sprom *out)
{
	if (!get_fallback_sprom)
		return -ENOENT;

	return get_fallback_sprom(bus, out);
}

/* http://bcm-v4.sipsolutions.net/802.11/IsSpromAvailable */
bool ssb_is_sprom_available(struct ssb_bus *bus)
{
	/* status register only exists on chipcomon rev >= 11 and we need check
	   for >= 31 only */
	/* this routine differs from specs as we do not access SPROM directly
	   on PCMCIA */
	if (bus->bustype == SSB_BUSTYPE_PCI &&
	    bus->chipco.dev &&	/* can be unavailable! */
	    bus->chipco.dev->id.revision >= 31)
		return bus->chipco.capabilities & SSB_CHIPCO_CAP_SPROM;

	return true;
}