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 += 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 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 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 91 out_kfree: 92 kfree(sprom); 93 out: 94 return err ? err : count; 95 } 96 97 /* Common sprom device-attribute store-handler */ 98 ssize_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 pr_err("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 pr_err("SPROM write: Could not thaw all devices\n"); 137 out_unlock: 138 mutex_unlock(&bus->sprom_mutex); 139 out_kfree: 140 kfree(sprom); 141 out: 142 if (res) 143 return res; 144 return err ? err : count; 145 } 146 147 /** 148 * ssb_arch_register_fallback_sprom - Registers a method providing a 149 * fallback SPROM if no SPROM is found. 150 * 151 * @sprom_callback: The callback function. 152 * 153 * With this function the architecture implementation may register a 154 * callback handler which fills the SPROM data structure. The fallback is 155 * only used for PCI based SSB devices, where no valid SPROM can be found 156 * in the shadow registers. 157 * 158 * This function is useful for weird architectures that have a half-assed 159 * SSB device hardwired to their PCI bus. 160 * 161 * Note that it does only work with PCI attached SSB devices. PCMCIA 162 * devices currently don't use this fallback. 163 * Architectures must provide the SPROM for native SSB devices anyway, so 164 * the fallback also isn't used for native devices. 165 * 166 * This function is available for architecture code, only. So it is not 167 * exported. 168 */ 169 int ssb_arch_register_fallback_sprom(int (*sprom_callback)(struct ssb_bus *bus, 170 struct ssb_sprom *out)) 171 { 172 if (get_fallback_sprom) 173 return -EEXIST; 174 get_fallback_sprom = sprom_callback; 175 176 return 0; 177 } 178 179 int ssb_fill_sprom_with_fallback(struct ssb_bus *bus, struct ssb_sprom *out) 180 { 181 if (!get_fallback_sprom) 182 return -ENOENT; 183 184 return get_fallback_sprom(bus, out); 185 } 186 187 /* http://bcm-v4.sipsolutions.net/802.11/IsSpromAvailable */ 188 bool ssb_is_sprom_available(struct ssb_bus *bus) 189 { 190 /* status register only exists on chipcomon rev >= 11 and we need check 191 for >= 31 only */ 192 /* this routine differs from specs as we do not access SPROM directly 193 on PCMCIA */ 194 if (bus->bustype == SSB_BUSTYPE_PCI && 195 bus->chipco.dev && /* can be unavailable! */ 196 bus->chipco.dev->id.revision >= 31) 197 return bus->chipco.capabilities & SSB_CHIPCO_CAP_SPROM; 198 199 return true; 200 } 201