V4L/DVB: ir-core: allow specifying multiple protocols at one open/write

With this change, it is now possible to do something like:
        su -c 'echo "none +rc-5 +nec" > /sys/class/rc/rc1/protocols'

This prevents the need of multiple opens, one for each protocol change,
and makes userspace application easier.
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/IR/ir-sysfs.c

@@ -117,62 +117,63 @@ static ssize_t store_protocols(struct device *d,
 	const char *tmp;
 	u64 type;
 	u64 mask;
-	int rc, i;
+	int rc, i, count = 0;
 	unsigned long flags;
 
-	tmp = skip_spaces(data);
-	if (*tmp == '\0') {
-		IR_dprintk(1, "Protocol not specified\n");
-		return -EINVAL;
-	} else if (*tmp == '+') {
-		enable = true;
-		disable = false;
-		tmp++;
-	} else if (*tmp == '-') {
-		enable = false;
-		disable = true;
-		tmp++;
-	} else {
-		enable = false;
-		disable = false;
-	}
+	if (ir_dev->props->driver_type == RC_DRIVER_SCANCODE)
+		type = ir_dev->rc_tab.ir_type;
+	else
+		type = ir_dev->raw->enabled_protocols;
 
+	while ((tmp = strsep((char **) &data, " \n")) != NULL) {
+		if (!*tmp)
+			break;
+
+		if (*tmp == '+') {
+			enable = true;
+			disable = false;
+			tmp++;
+		} else if (*tmp == '-') {
+			enable = false;
+			disable = true;
+			tmp++;
+		} else {
+			enable = false;
+			disable = false;
+		}
 
-	if (!enable && !disable && !strncasecmp(tmp, PROTO_NONE, sizeof(PROTO_NONE))) {
-		mask = 0;
-		tmp += sizeof(PROTO_NONE);
-	} else {
-		for (i = 0; i < ARRAY_SIZE(proto_names); i++) {
-			if (!strncasecmp(tmp, proto_names[i].name, strlen(proto_names[i].name))) {
-				tmp += strlen(proto_names[i].name);
-				mask = proto_names[i].type;
-				break;
+		if (!enable && !disable && !strncasecmp(tmp, PROTO_NONE, sizeof(PROTO_NONE))) {
+			tmp += sizeof(PROTO_NONE);
+			mask = 0;
+			count++;
+		} else {
+			for (i = 0; i < ARRAY_SIZE(proto_names); i++) {
+				if (!strncasecmp(tmp, proto_names[i].name, strlen(proto_names[i].name))) {
+					tmp += strlen(proto_names[i].name);
+					mask = proto_names[i].type;
+					break;
+				}
 			}
+			if (i == ARRAY_SIZE(proto_names)) {
+				IR_dprintk(1, "Unknown protocol: '%s'\n", tmp);
+				return -EINVAL;
+			}
+			count++;
 		}
-		if (i == ARRAY_SIZE(proto_names)) {
-			IR_dprintk(1, "Unknown protocol\n");
-			return -EINVAL;
-		}
+
+		if (enable)
+			type |= mask;
+		else if (disable)
+			type &= ~mask;
+		else
+			type = mask;
 	}
 
-	tmp = skip_spaces(tmp);
-	if (*tmp != '\0') {
-		IR_dprintk(1, "Invalid trailing characters\n");
+	if (!count) {
+		IR_dprintk(1, "Protocol not specified\n");
 		return -EINVAL;
 	}
 
-	if (ir_dev->props->driver_type == RC_DRIVER_SCANCODE)
-		type = ir_dev->rc_tab.ir_type;
-	else
-		type = ir_dev->raw->enabled_protocols;
-
-	if (enable)
-		type |= mask;
-	else if (disable)
-		type &= ~mask;
-	else
-		type = mask;
-
 	if (ir_dev->props && ir_dev->props->change_protocol) {
 		rc = ir_dev->props->change_protocol(ir_dev->props->priv,
 						    type);
@@ -191,7 +192,6 @@ static ssize_t store_protocols(struct device *d,
 		ir_dev->raw->enabled_protocols = type;
 	}
 
-
 	IR_dprintk(1, "Current protocol(s): 0x%llx\n",
 		   (long long)type);