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  • only in /asuswrt-rt-n18u-9.0.0.4.380.2695/release/src-rt-6.x.4708/linux/linux-2.6.36/drivers/ssb/
1/*
2 * Sonics Silicon Backplane
3 * Common SPROM support routines
4 *
5 * Copyright (C) 2005-2008 Michael Buesch <mb@bu3sch.de>
6 * Copyright (C) 2005 Martin Langer <martin-langer@gmx.de>
7 * Copyright (C) 2005 Stefano Brivio <st3@riseup.net>
8 * Copyright (C) 2005 Danny van Dyk <kugelfang@gentoo.org>
9 * Copyright (C) 2005 Andreas Jaggi <andreas.jaggi@waterwave.ch>
10 *
11 * Licensed under the GNU/GPL. See COPYING for details.
12 */
13
14#include "ssb_private.h"
15
16#include <linux/ctype.h>
17#include <linux/slab.h>
18
19
20static const struct ssb_sprom *fallback_sprom;
21
22
23static int sprom2hex(const u16 *sprom, char *buf, size_t buf_len,
24		     size_t sprom_size_words)
25{
26	int i, pos = 0;
27
28	for (i = 0; i < sprom_size_words; i++)
29		pos += snprintf(buf + pos, buf_len - pos - 1,
30				"%04X", swab16(sprom[i]) & 0xFFFF);
31	pos += snprintf(buf + pos, buf_len - pos - 1, "\n");
32
33	return pos + 1;
34}
35
36static int hex2sprom(u16 *sprom, const char *dump, size_t len,
37		     size_t sprom_size_words)
38{
39	char c, tmp[5] = { 0 };
40	int err, cnt = 0;
41	unsigned long parsed;
42
43	/* Strip whitespace at the end. */
44	while (len) {
45		c = dump[len - 1];
46		if (!isspace(c) && c != '\0')
47			break;
48		len--;
49	}
50	/* Length must match exactly. */
51	if (len != sprom_size_words * 4)
52		return -EINVAL;
53
54	while (cnt < sprom_size_words) {
55		memcpy(tmp, dump, 4);
56		dump += 4;
57		err = strict_strtoul(tmp, 16, &parsed);
58		if (err)
59			return err;
60		sprom[cnt++] = swab16((u16)parsed);
61	}
62
63	return 0;
64}
65
66/* Common sprom device-attribute show-handler */
67ssize_t ssb_attr_sprom_show(struct ssb_bus *bus, char *buf,
68			    int (*sprom_read)(struct ssb_bus *bus, u16 *sprom))
69{
70	u16 *sprom;
71	int err = -ENOMEM;
72	ssize_t count = 0;
73	size_t sprom_size_words = bus->sprom_size;
74
75	sprom = kcalloc(sprom_size_words, sizeof(u16), GFP_KERNEL);
76	if (!sprom)
77		goto out;
78
79	/* Use interruptible locking, as the SPROM write might
80	 * be holding the lock for several seconds. So allow userspace
81	 * to cancel operation. */
82	err = -ERESTARTSYS;
83	if (mutex_lock_interruptible(&bus->sprom_mutex))
84		goto out_kfree;
85	err = sprom_read(bus, sprom);
86	mutex_unlock(&bus->sprom_mutex);
87
88	if (!err)
89		count = sprom2hex(sprom, buf, PAGE_SIZE, sprom_size_words);
90
91out_kfree:
92	kfree(sprom);
93out:
94	return err ? err : count;
95}
96
97/* Common sprom device-attribute store-handler */
98ssize_t ssb_attr_sprom_store(struct ssb_bus *bus,
99			     const char *buf, size_t count,
100			     int (*sprom_check_crc)(const u16 *sprom, size_t size),
101			     int (*sprom_write)(struct ssb_bus *bus, const u16 *sprom))
102{
103	u16 *sprom;
104	int res = 0, err = -ENOMEM;
105	size_t sprom_size_words = bus->sprom_size;
106	struct ssb_freeze_context freeze;
107
108	sprom = kcalloc(bus->sprom_size, sizeof(u16), GFP_KERNEL);
109	if (!sprom)
110		goto out;
111	err = hex2sprom(sprom, buf, count, sprom_size_words);
112	if (err) {
113		err = -EINVAL;
114		goto out_kfree;
115	}
116	err = sprom_check_crc(sprom, sprom_size_words);
117	if (err) {
118		err = -EINVAL;
119		goto out_kfree;
120	}
121
122	/* Use interruptible locking, as the SPROM write might
123	 * be holding the lock for several seconds. So allow userspace
124	 * to cancel operation. */
125	err = -ERESTARTSYS;
126	if (mutex_lock_interruptible(&bus->sprom_mutex))
127		goto out_kfree;
128	err = ssb_devices_freeze(bus, &freeze);
129	if (err) {
130		ssb_printk(KERN_ERR PFX "SPROM write: Could not freeze all devices\n");
131		goto out_unlock;
132	}
133	res = sprom_write(bus, sprom);
134	err = ssb_devices_thaw(&freeze);
135	if (err)
136		ssb_printk(KERN_ERR PFX "SPROM write: Could not thaw all devices\n");
137out_unlock:
138	mutex_unlock(&bus->sprom_mutex);
139out_kfree:
140	kfree(sprom);
141out:
142	if (res)
143		return res;
144	return err ? err : count;
145}
146
147/**
148 * ssb_arch_set_fallback_sprom - Set a fallback SPROM for use if no SPROM is found.
149 *
150 * @sprom: The SPROM data structure to register.
151 *
152 * With this function the architecture implementation may register a fallback
153 * SPROM data structure. The fallback is only used for PCI based SSB devices,
154 * where no valid SPROM can be found in the shadow registers.
155 *
156 * This function is useful for weird architectures that have a half-assed SSB device
157 * hardwired to their PCI bus.
158 *
159 * Note that it does only work with PCI attached SSB devices. PCMCIA devices currently
160 * don't use this fallback.
161 * Architectures must provide the SPROM for native SSB devices anyway,
162 * so the fallback also isn't used for native devices.
163 *
164 * This function is available for architecture code, only. So it is not exported.
165 */
166int ssb_arch_set_fallback_sprom(const struct ssb_sprom *sprom)
167{
168	if (fallback_sprom)
169		return -EEXIST;
170	fallback_sprom = sprom;
171
172	return 0;
173}
174
175const struct ssb_sprom *ssb_get_fallback_sprom(void)
176{
177	return fallback_sprom;
178}
179
180/* http://bcm-v4.sipsolutions.net/802.11/IsSpromAvailable */
181bool ssb_is_sprom_available(struct ssb_bus *bus)
182{
183	/* status register only exists on chipcomon rev >= 11 and we need check
184	   for >= 31 only */
185	/* this routine differs from specs as we do not access SPROM directly
186	   on PCMCIA */
187	if (bus->bustype == SSB_BUSTYPE_PCI &&
188	    bus->chipco.dev &&	/* can be unavailible! */
189	    bus->chipco.dev->id.revision >= 31)
190		return bus->chipco.capabilities & SSB_CHIPCO_CAP_SPROM;
191
192	return true;
193}
194