swh:1:snp:c3bf2749e3476071fa748f67b0ffa2fdc5fe49d9
Tip revision: d5226fa6dbae0569ee43ecfc08bdcd6770fc4755 authored by Linus Torvalds on 27 January 2020, 00:23:03 UTC
Linux 5.5
Linux 5.5
Tip revision: d5226fa
sprom.c
/*
* 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 = kstrtoul(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) {
pr_err("SPROM write: Could not freeze all devices\n");
goto out_unlock;
}
res = sprom_write(bus, sprom);
err = ssb_devices_thaw(&freeze);
if (err)
pr_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;
}