diff options
Diffstat (limited to 'net/dsa/master.c')
| -rw-r--r-- | net/dsa/master.c | 39 |
1 files changed, 38 insertions, 1 deletions
diff --git a/net/dsa/master.c b/net/dsa/master.c index cb3a5cf99b25..052a977914a6 100644 --- a/net/dsa/master.c +++ b/net/dsa/master.c @@ -280,7 +280,44 @@ static ssize_t tagging_show(struct device *d, struct device_attribute *attr, return sprintf(buf, "%s\n", dsa_tag_protocol_to_str(cpu_dp->tag_ops)); } -static DEVICE_ATTR_RO(tagging); + +static ssize_t tagging_store(struct device *d, struct device_attribute *attr, + const char *buf, size_t count) +{ + const struct dsa_device_ops *new_tag_ops, *old_tag_ops; + struct net_device *dev = to_net_dev(d); + struct dsa_port *cpu_dp = dev->dsa_ptr; + int err; + + old_tag_ops = cpu_dp->tag_ops; + new_tag_ops = dsa_find_tagger_by_name(buf); + /* Bad tagger name, or module is not loaded? */ + if (IS_ERR(new_tag_ops)) + return PTR_ERR(new_tag_ops); + + if (new_tag_ops == old_tag_ops) + /* Drop the temporarily held duplicate reference, since + * the DSA switch tree uses this tagger. + */ + goto out; + + err = dsa_tree_change_tag_proto(cpu_dp->ds->dst, dev, new_tag_ops, + old_tag_ops); + if (err) { + /* On failure the old tagger is restored, so we don't need the + * driver for the new one. + */ + dsa_tag_driver_put(new_tag_ops); + return err; + } + + /* On success we no longer need the module for the old tagging protocol + */ +out: + dsa_tag_driver_put(old_tag_ops); + return count; +} +static DEVICE_ATTR_RW(tagging); static struct attribute *dsa_slave_attrs[] = { &dev_attr_tagging.attr, |