From da2c398e59d6b47260e4198559b9f284e3b557e0 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Thu, 18 Aug 2022 14:54:58 +0300 Subject: net: dsa: avoid dsa_port_link_{,un}register_of() calls with platform data dsa_port_link_register_of() and dsa_port_link_unregister_of() are not written with the fact in mind that they can be called with a dp->dn that is NULL (as evidenced even by the _of suffix in their name), but this is exactly what happens. How this behaves will differ depending on whether the backing driver implements ->adjust_link() or not. If it doesn't, the "if (of_phy_is_fixed_link(dp->dn) || phy_np)" condition will return false, and dsa_port_link_register_of() will do nothing and return 0. If the driver does implement ->adjust_link(), the "if (of_phy_is_fixed_link(dp->dn))" condition will return false (dp->dn is NULL) and we will call dsa_port_setup_phy_of(). This will call dsa_port_get_phy_device(), which will also return NULL, and we will also do nothing and return 0. It is hard to maintain this code and make future changes to it in this state, so just suppress calls to these 2 functions if dp->dn is NULL. The only functional effect is that if the driver does implement ->adjust_link(), we'll stop printing this to the console: Using legacy PHYLIB callbacks. Please migrate to PHYLINK! but instead we'll always print: [ 8.539848] dsa-loop fixed-0:1f: skipping link registration for CPU port 5 This is for the better anyway, since "using legacy phylib callbacks" was misleading information - we weren't issuing _any_ callbacks due to dsa_port_get_phy_device() returning NULL. Signed-off-by: Vladimir Oltean Signed-off-by: Jakub Kicinski --- net/dsa/dsa2.c | 34 ++++++++++++++++++++++++---------- 1 file changed, 24 insertions(+), 10 deletions(-) (limited to 'net/dsa') diff --git a/net/dsa/dsa2.c b/net/dsa/dsa2.c index cac48a741f27..12479707bf96 100644 --- a/net/dsa/dsa2.c +++ b/net/dsa/dsa2.c @@ -469,10 +469,16 @@ static int dsa_port_setup(struct dsa_port *dp) dsa_port_disable(dp); break; case DSA_PORT_TYPE_CPU: - err = dsa_port_link_register_of(dp); - if (err) - break; - dsa_port_link_registered = true; + if (dp->dn) { + err = dsa_port_link_register_of(dp); + if (err) + break; + dsa_port_link_registered = true; + } else { + dev_warn(ds->dev, + "skipping link registration for CPU port %d\n", + dp->index); + } err = dsa_port_enable(dp, NULL); if (err) @@ -481,10 +487,16 @@ static int dsa_port_setup(struct dsa_port *dp) break; case DSA_PORT_TYPE_DSA: - err = dsa_port_link_register_of(dp); - if (err) - break; - dsa_port_link_registered = true; + if (dp->dn) { + err = dsa_port_link_register_of(dp); + if (err) + break; + dsa_port_link_registered = true; + } else { + dev_warn(ds->dev, + "skipping link registration for DSA port %d\n", + dp->index); + } err = dsa_port_enable(dp, NULL); if (err) @@ -577,11 +589,13 @@ static void dsa_port_teardown(struct dsa_port *dp) break; case DSA_PORT_TYPE_CPU: dsa_port_disable(dp); - dsa_port_link_unregister_of(dp); + if (dp->dn) + dsa_port_link_unregister_of(dp); break; case DSA_PORT_TYPE_DSA: dsa_port_disable(dp); - dsa_port_link_unregister_of(dp); + if (dp->dn) + dsa_port_link_unregister_of(dp); break; case DSA_PORT_TYPE_USER: if (dp->slave) { -- cgit v1.2.3