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| author | Vladimir Oltean <vladimir.oltean@nxp.com> | 2022-11-15 04:18:44 +0300 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2022-11-18 08:16:41 +0300 |
| commit | 94793a56b3df0ff2b8c5680f926c19effd8b9ccc (patch) | |
| tree | 0346cda8f1689f47463754ac115864868a69a058 /net/dsa/tag_rtl4_a.c | |
| parent | 2610937d7e95d010e7301277408457cd385a9288 (diff) | |
| download | linux-94793a56b3df0ff2b8c5680f926c19effd8b9ccc.tar.xz | |
net: dsa: provide a second modalias to tag proto drivers based on their name
Currently, tagging protocol drivers have a modalias of
"dsa_tag:id-<number>", where the number is one of DSA_TAG_PROTO_*_VALUE.
This modalias makes it possible for the request_module() call in
dsa_tag_driver_get() to work, given the input it has - an integer
returned by ds->ops->get_tag_protocol().
It is also possible to change tagging protocols at (pseudo-)runtime, via
sysfs or via device tree, and this works via the name string of the
tagging protocol rather than via its id (DSA_TAG_PROTO_*_VALUE).
In the latter case, there is no request_module() call, because there is
no association that the DSA core has between the string name and the ID,
to construct the modalias. The module is simply assumed to have been
inserted. This is actually slightly problematic when the tagging
protocol change should take place at probe time, since it's expected
that the dependency module should get autoloaded.
For this purpose, let's introduce a second modalias, so that the DSA
core can call request_module() by name. There is no reason to make the
modalias by name optional, so just modify the MODULE_ALIAS_DSA_TAG_DRIVER()
macro to take both the ID and the name as arguments, and generate two
modaliases behind the scenes.
Suggested-by: Michael Walle <michael@walle.cc>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Michael Walle <michael@walle.cc> # on kontron-sl28 w/ ocelot_8021q
Tested-by: Michael Walle <michael@walle.cc>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/dsa/tag_rtl4_a.c')
| -rw-r--r-- | net/dsa/tag_rtl4_a.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/net/dsa/tag_rtl4_a.c b/net/dsa/tag_rtl4_a.c index 6d928ee3ef7a..18b52d77d200 100644 --- a/net/dsa/tag_rtl4_a.c +++ b/net/dsa/tag_rtl4_a.c @@ -20,6 +20,8 @@ #include "dsa_priv.h" +#define RTL4_A_NAME "rtl4a" + #define RTL4_A_HDR_LEN 4 #define RTL4_A_ETHERTYPE 0x8899 #define RTL4_A_PROTOCOL_SHIFT 12 @@ -112,7 +114,7 @@ static struct sk_buff *rtl4a_tag_rcv(struct sk_buff *skb, } static const struct dsa_device_ops rtl4a_netdev_ops = { - .name = "rtl4a", + .name = RTL4_A_NAME, .proto = DSA_TAG_PROTO_RTL4_A, .xmit = rtl4a_tag_xmit, .rcv = rtl4a_tag_rcv, @@ -121,4 +123,4 @@ static const struct dsa_device_ops rtl4a_netdev_ops = { module_dsa_tag_driver(rtl4a_netdev_ops); MODULE_LICENSE("GPL"); -MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_RTL4_A); +MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_RTL4_A, RTL4_A_NAME); |