w1: support auto-load of w1_bq27000 module.

1/ change request_module call to zero-pad single digit
   family numbers.  This appears to be the intention of
   the code, but not what it actually does.

   This means that the alias created for W1_FAMILY_SMEM_01
   might actually be useful.

2/ Define a family name for the BQ27000 battery charge monitor.
   Unfortunately this is the same number as W1_FAMILY_SMEM_01
   so if both a compiled on a system, one module might need to
   be blacklisted.

3/ Add a MODULE_ALIAS for the bq27000.
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/w1/slaves/w1_bq27000.c

@@ -88,7 +88,7 @@ static struct w1_family_ops w1_bq27000_fops = {
 };
 
 static struct w1_family w1_bq27000_family = {
-	.fid = 1,
+	.fid = W1_FAMILY_BQ27000,
 	.fops = &w1_bq27000_fops,
 };
 
@@ -111,7 +111,7 @@ module_exit(w1_bq27000_exit);
 
 module_param(F_ID, int, S_IRUSR);
 MODULE_PARM_DESC(F_ID, "1-wire slave FID for BQ device");
-
+MODULE_ALIAS("w1-family-" __stringify(W1_FAMILY_BQ27000));
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Texas Instruments Ltd");
 MODULE_DESCRIPTION("HDQ/1-wire slave driver bq27000 battery monitor chip");

drivers/w1/w1.c

@@ -727,7 +727,7 @@ int w1_attach_slave_device(struct w1_master *dev, struct w1_reg_num *rn)
 
 	/* slave modules need to be loaded in a context with unlocked mutex */
 	mutex_unlock(&dev->mutex);
-	request_module("w1-family-0x%0x", rn->family);
+	request_module("w1-family-0x%02x", rn->family);
 	mutex_lock(&dev->mutex);
 
 	spin_lock(&w1_flock);

drivers/w1/w1_family.h

@@ -27,6 +27,7 @@
 #include <linux/atomic.h>
 
 #define W1_FAMILY_DEFAULT	0
+#define W1_FAMILY_BQ27000	0x01
 #define W1_FAMILY_SMEM_01	0x01
 #define W1_FAMILY_SMEM_81	0x81
 #define W1_THERM_DS18S20 	0x10