drivers/ssb/sprom.c

   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
  17 static int sprom2hex(const u16 *sprom, char *buf, size_t buf_len,
  18                      size_t sprom_size_words)
  19 {
  20         int i, pos = 0;
  21
  22         for (i = 0; i < sprom_size_words; i++)
  23                 pos += snprintf(buf + pos, buf_len - pos - 1,
  24                                 "%04X", swab16(sprom[i]) & 0xFFFF);
  25         pos += snprintf(buf + pos, buf_len - pos - 1, "\n");
  26
  27         return pos + 1;
  28 }
  29
  30 static int hex2sprom(u16 *sprom, const char *dump, size_t len,
  31                      size_t sprom_size_words)
  32 {
  33         char tmp[5] = { 0 };
  34         int cnt = 0;
  35         unsigned long parsed;
  36
  37         if (len < sprom_size_words * 2)
  38                 return -EINVAL;
  39
  40         while (cnt < sprom_size_words) {
  41                 memcpy(tmp, dump, 4);
  42                 dump += 4;
  43                 parsed = simple_strtoul(tmp, NULL, 16);
  44                 sprom[cnt++] = swab16((u16)parsed);
  45         }
  46
  47         return 0;
  48 }
  49
  50 /* Common sprom device-attribute show-handler */
  51 ssize_t ssb_attr_sprom_show(struct ssb_bus *bus, char *buf,
  52                             int (*sprom_read)(struct ssb_bus *bus, u16 *sprom))
  53 {
  54         u16 *sprom;
  55         int err = -ENOMEM;
  56         ssize_t count = 0;
  57         size_t sprom_size_words = bus->sprom_size;
  58
  59         sprom = kcalloc(sprom_size_words, sizeof(u16), GFP_KERNEL);
  60         if (!sprom)
  61                 goto out;
  62
  63         /* Use interruptible locking, as the SPROM write might
  64          * be holding the lock for several seconds. So allow userspace
  65          * to cancel operation. */
  66         err = -ERESTARTSYS;
  67         if (mutex_lock_interruptible(&bus->sprom_mutex))
  68                 goto out_kfree;
  69         err = sprom_read(bus, sprom);
  70         mutex_unlock(&bus->sprom_mutex);
  71
  72         if (!err)
  73                 count = sprom2hex(sprom, buf, PAGE_SIZE, sprom_size_words);
  74
  75 out_kfree:
  76         kfree(sprom);
  77 out:
  78         return err ? err : count;
  79 }
  80
  81 /* Common sprom device-attribute store-handler */
  82 ssize_t ssb_attr_sprom_store(struct ssb_bus *bus,
  83                              const char *buf, size_t count,
  84                              int (*sprom_check_crc)(const u16 *sprom, size_t size),
  85                              int (*sprom_write)(struct ssb_bus *bus, const u16 *sprom))
  86 {
  87         u16 *sprom;
  88         int res = 0, err = -ENOMEM;
  89         size_t sprom_size_words = bus->sprom_size;
  90
  91         sprom = kcalloc(bus->sprom_size, sizeof(u16), GFP_KERNEL);
  92         if (!sprom)
  93                 goto out;
  94         err = hex2sprom(sprom, buf, count, sprom_size_words);
  95         if (err) {
  96                 err = -EINVAL;
  97                 goto out_kfree;
  98         }
  99         err = sprom_check_crc(sprom, sprom_size_words);
 100         if (err) {
 101                 err = -EINVAL;
 102                 goto out_kfree;
 103         }
 104
 105         /* Use interruptible locking, as the SPROM write might
 106          * be holding the lock for several seconds. So allow userspace
 107          * to cancel operation. */
 108         err = -ERESTARTSYS;
 109         if (mutex_lock_interruptible(&bus->sprom_mutex))
 110                 goto out_kfree;
 111         err = ssb_devices_freeze(bus);
 112         if (err == -EOPNOTSUPP) {
 113                 ssb_printk(KERN_ERR PFX "SPROM write: Could not freeze devices. "
 114                            "No suspend support. Is CONFIG_PM enabled?\n");
 115                 goto out_unlock;
 116         }
 117         if (err) {
 118                 ssb_printk(KERN_ERR PFX "SPROM write: Could not freeze all devices\n");
 119                 goto out_unlock;
 120         }
 121         res = sprom_write(bus, sprom);
 122         err = ssb_devices_thaw(bus);
 123         if (err)
 124                 ssb_printk(KERN_ERR PFX "SPROM write: Could not thaw all devices\n");
 125 out_unlock:
 126         mutex_unlock(&bus->sprom_mutex);
 127 out_kfree:
 128         kfree(sprom);
 129 out:
 130         if (res)
 131                 return res;
 132         return err ? err : count;
 133 }