ssb: Add SPROM/invariants support for PCMCIA devices

This adds support for reading/writing the SPROM invariants
for PCMCIA based devices.

Signed-off-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/ssb/sprom.c b/drivers/ssb/sprom.c
new file mode 100644
index 0000000..3668edb
--- /dev/null
+++ b/drivers/ssb/sprom.c
@@ -0,0 +1,133 @@
+/*
+ * Sonics Silicon Backplane
+ * Common SPROM support routines
+ *
+ * Copyright (C) 2005-2008 Michael Buesch <mb@bu3sch.de>
+ * 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"
+
+
+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 tmp[5] = { 0 };
+	int cnt = 0;
+	unsigned long parsed;
+
+	if (len < sprom_size_words * 2)
+		return -EINVAL;
+
+	while (cnt < sprom_size_words) {
+		memcpy(tmp, dump, 4);
+		dump += 4;
+		parsed = simple_strtoul(tmp, NULL, 16);
+		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;
+
+	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);
+	if (err == -EOPNOTSUPP) {
+		ssb_printk(KERN_ERR PFX "SPROM write: Could not freeze devices. "
+			   "No suspend support. Is CONFIG_PM enabled?\n");
+		goto out_unlock;
+	}
+	if (err) {
+		ssb_printk(KERN_ERR PFX "SPROM write: Could not freeze all devices\n");
+		goto out_unlock;
+	}
+	res = sprom_write(bus, sprom);
+	err = ssb_devices_thaw(bus);
+	if (err)
+		ssb_printk(KERN_ERR PFX "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;
+}