w1: added w1 reset command

Command which allows to reset the bus.
Signed-off-by: NEvgeniy Polyakov <zbr@ioremap.net>
Cc: Paul Alfille <paul.alfille@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Documentation/w1/w1.netlink

@@ -112,6 +112,12 @@ cn_msg->len = sizeof(struct w1_netlink_msg) +
 	      sizeof(struct w1_netlink_cmd) +
 	      N*8;
 
+W1 reset command.
+[cn_msg]
+  [w1_netlink_msg type = W1_MASTER_CMD
+  	id is equal to the bus master id to use for searching]
+  [w1_netlink_cmd cmd = W1_CMD_RESET]
+
 Operation steps in w1 core when new command is received.
 =======================================================
 

drivers/w1/w1_netlink.c

@@ -197,6 +197,9 @@ static int w1_process_command_master(struct w1_master *dev, struct cn_msg *req_m
 	case W1_CMD_TOUCH:
 		err = w1_process_command_io(dev, msg, hdr, cmd);
 		break;
+	case W1_CMD_RESET:
+		err = w1_reset_bus(dev);
+		break;
 	default:
 		cmd->res = EINVAL;
 		cn_netlink_send(msg, 0, GFP_KERNEL);

drivers/w1/w1_netlink.h

@@ -58,6 +58,7 @@ enum w1_commands {
 	W1_CMD_SEARCH,
 	W1_CMD_ALARM_SEARCH,
 	W1_CMD_TOUCH,
+	W1_CMD_RESET,
 	W1_CMD_MAX,
 };