1 /* 2 * Sonics Silicon Backplane 3 * Common SPROM support routines 4 * 5 * Copyright (C) 2005-2008 Michael Buesch <m@bues.ch> 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 20 static int(*get_fallback_sprom)(struct ssb_bus *dev, struct ssb_sprom *out); 21 22 23 static 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 += scnprintf(buf + pos, buf_len - pos - 1, 30 "%04X", swab16(sprom[i]) & 0xFFFF); 31 pos += scnprintf(buf + pos, buf_len - pos - 1, "\n"); 32 33 return pos + 1; 34 } 35 36 static 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 = kstrtoul(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 */ 67 ssize_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 */ 83 err = -ERESTARTSYS; 84 if (mutex_lock_interruptible(&bus->sprom_mutex)) 85 goto out_kfree; 86 err = sprom_read(bus, sprom); 87 mutex_unlock(&bus->sprom_mutex); 88 89 if (!err) 90 count = sprom2hex(sprom, buf, PAGE_SIZE, sprom_size_words); 91 92 out_kfree: 93 kfree(sprom); 94 out: 95 return err ? err : count; 96 } 97 98 /* Common sprom device-attribute store-handler */ 99 ssize_t ssb_attr_sprom_store(struct ssb_bus *bus, 100 const char *buf, size_t count, 101 int (*sprom_check_crc)(const u16 *sprom, size_t size), 102 int (*sprom_write)(struct ssb_bus *bus, const u16 *sprom)) 103 { 104 u16 *sprom; 105 int res = 0, err = -ENOMEM; 106 size_t sprom_size_words = bus->sprom_size; 107 struct ssb_freeze_context freeze; 108 109 sprom = kcalloc(bus->sprom_size, sizeof(u16), GFP_KERNEL); 110 if (!sprom) 111 goto out; 112 err = hex2sprom(sprom, buf, count, sprom_size_words); 113 if (err) { 114 err = -EINVAL; 115 goto out_kfree; 116 } 117 err = sprom_check_crc(sprom, sprom_size_words); 118 if (err) { 119 err = -EINVAL; 120 goto out_kfree; 121 } 122 123 /* Use interruptible locking, as the SPROM write might 124 * be holding the lock for several seconds. So allow userspace 125 * to cancel operation. 126 */ 127 err = -ERESTARTSYS; 128 if (mutex_lock_interruptible(&bus->sprom_mutex)) 129 goto out_kfree; 130 err = ssb_devices_freeze(bus, &freeze); 131 if (err) { 132 pr_err("SPROM write: Could not freeze all devices\n"); 133 goto out_unlock; 134 } 135 res = sprom_write(bus, sprom); 136 err = ssb_devices_thaw(&freeze); 137 if (err) 138 pr_err("SPROM write: Could not thaw all devices\n"); 139 out_unlock: 140 mutex_unlock(&bus->sprom_mutex); 141 out_kfree: 142 kfree(sprom); 143 out: 144 if (res) 145 return res; 146 return err ? err : count; 147 } 148 149 /** 150 * ssb_arch_register_fallback_sprom - Registers a method providing a 151 * fallback SPROM if no SPROM is found. 152 * 153 * @sprom_callback: The callback function. 154 * 155 * With this function the architecture implementation may register a 156 * callback handler which fills the SPROM data structure. The fallback is 157 * only used for PCI based SSB devices, where no valid SPROM can be found 158 * in the shadow registers. 159 * 160 * This function is useful for weird architectures that have a half-assed 161 * SSB device hardwired to their PCI bus. 162 * 163 * Note that it does only work with PCI attached SSB devices. PCMCIA 164 * devices currently don't use this fallback. 165 * Architectures must provide the SPROM for native SSB devices anyway, so 166 * the fallback also isn't used for native devices. 167 * 168 * This function is available for architecture code, only. So it is not 169 * exported. 170 */ 171 int ssb_arch_register_fallback_sprom(int (*sprom_callback)(struct ssb_bus *bus, 172 struct ssb_sprom *out)) 173 { 174 if (get_fallback_sprom) 175 return -EEXIST; 176 get_fallback_sprom = sprom_callback; 177 178 return 0; 179 } 180 181 int ssb_fill_sprom_with_fallback(struct ssb_bus *bus, struct ssb_sprom *out) 182 { 183 if (!get_fallback_sprom) 184 return -ENOENT; 185 186 return get_fallback_sprom(bus, out); 187 } 188 189 /* https://bcm-v4.sipsolutions.net/802.11/IsSpromAvailable */ 190 bool ssb_is_sprom_available(struct ssb_bus *bus) 191 { 192 /* status register only exists on chipcomon rev >= 11 and we need check 193 * for >= 31 only 194 */ 195 /* this routine differs from specs as we do not access SPROM directly 196 * on PCMCIA 197 */ 198 if (bus->bustype == SSB_BUSTYPE_PCI && 199 bus->chipco.dev && /* can be unavailable! */ 200 bus->chipco.dev->id.revision >= 31) 201 return bus->chipco.capabilities & SSB_CHIPCO_CAP_SPROM; 202 203 return true; 204 } 205