| Message ID | 20201028221427.22968-4-kabel@kernel.org (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | Support for RollBall 10G copper SFP modules | expand |
On Wed, Oct 28, 2020 at 11:14:25PM +0100, Marek Behún wrote: > Instead of configuring the I2C mdiobus when SFP driver is probed, > configure/destroy the mdiobus when SFP transceiver is plugged/unplugged. > > This way we can tell the mdio-i2c code which protocol to use for each > SFP transceiver. > > Signed-off-by: Marek Behún <kabel@kernel.org> > Cc: Andrew Lunn <andrew@lunn.ch> > Cc: Russell King <rmk+kernel@armlinux.org.uk> > --- > drivers/net/phy/sfp.c | 26 ++++++++++++++++++++++---- > 1 file changed, 22 insertions(+), 4 deletions(-) > > diff --git a/drivers/net/phy/sfp.c b/drivers/net/phy/sfp.c > index b1f9fc3a5584..a392d5fc6ab4 100644 > --- a/drivers/net/phy/sfp.c > +++ b/drivers/net/phy/sfp.c > @@ -399,9 +399,6 @@ static int sfp_i2c_write(struct sfp *sfp, bool a2, u8 dev_addr, void *buf, > > static int sfp_i2c_configure(struct sfp *sfp, struct i2c_adapter *i2c) > { > - struct mii_bus *i2c_mii; > - int ret; > - > if (!i2c_check_functionality(i2c, I2C_FUNC_I2C)) > return -EINVAL; > > @@ -409,7 +406,15 @@ static int sfp_i2c_configure(struct sfp *sfp, struct i2c_adapter *i2c) > sfp->read = sfp_i2c_read; > sfp->write = sfp_i2c_write; > > - i2c_mii = mdio_i2c_alloc(sfp->dev, i2c, MDIO_I2C_DEFAULT); > + return 0; > +} > + > +static int sfp_i2c_mdiobus_configure(struct sfp *sfp, enum mdio_i2c_type type) > +{ > + struct mii_bus *i2c_mii; > + int ret; > + > + i2c_mii = mdio_i2c_alloc(sfp->dev, sfp->i2c, type); > if (IS_ERR(i2c_mii)) > return PTR_ERR(i2c_mii); > > @@ -427,6 +432,12 @@ static int sfp_i2c_configure(struct sfp *sfp, struct i2c_adapter *i2c) > return 0; > } > > +static void sfp_i2c_mdiobus_destroy(struct sfp *sfp) > +{ > + mdiobus_unregister(sfp->i2c_mii); > + sfp->i2c_mii = NULL; > +} > + > /* Interface */ > static int sfp_read(struct sfp *sfp, bool a2, u8 addr, void *buf, size_t len) > { > @@ -1768,6 +1779,11 @@ static int sfp_sm_mod_probe(struct sfp *sfp, bool report) > else > sfp->module_t_start_up = T_START_UP; > > + /* Configure mdiobus */ > + ret = sfp_i2c_mdiobus_configure(sfp, MDIO_I2C_DEFAULT); > + if (ret < 0) > + return ret; > + return sfp_i2c_mdiobus_configure(sfp, MDIO_I2C_DEFAULT); would be a simpler way to write this. However, I suggest handling this elsewhere due to the point below. > @@ -1778,6 +1794,8 @@ static void sfp_sm_mod_remove(struct sfp *sfp) > > sfp_hwmon_remove(sfp); > > + sfp_i2c_mdiobus_destroy(sfp); > + This doesn't seem like the right place to handle this. This is called from the module state machine (sfp_sm_module()) which is run before the main state machine (sfp_sm_main()). The PHY is unregistered in the main state machine, which means you're destroying the MII bus before the PHY. I guess what saves us from crashing is the refcounting, but this doesn't seem to me to be particularly good. Maybe create the MII bus after the "init_done" label, and destroy it after we've called sfp_sm_phy_detach() ?
diff --git a/drivers/net/phy/sfp.c b/drivers/net/phy/sfp.c index b1f9fc3a5584..a392d5fc6ab4 100644 --- a/drivers/net/phy/sfp.c +++ b/drivers/net/phy/sfp.c @@ -399,9 +399,6 @@ static int sfp_i2c_write(struct sfp *sfp, bool a2, u8 dev_addr, void *buf, static int sfp_i2c_configure(struct sfp *sfp, struct i2c_adapter *i2c) { - struct mii_bus *i2c_mii; - int ret; - if (!i2c_check_functionality(i2c, I2C_FUNC_I2C)) return -EINVAL; @@ -409,7 +406,15 @@ static int sfp_i2c_configure(struct sfp *sfp, struct i2c_adapter *i2c) sfp->read = sfp_i2c_read; sfp->write = sfp_i2c_write; - i2c_mii = mdio_i2c_alloc(sfp->dev, i2c, MDIO_I2C_DEFAULT); + return 0; +} + +static int sfp_i2c_mdiobus_configure(struct sfp *sfp, enum mdio_i2c_type type) +{ + struct mii_bus *i2c_mii; + int ret; + + i2c_mii = mdio_i2c_alloc(sfp->dev, sfp->i2c, type); if (IS_ERR(i2c_mii)) return PTR_ERR(i2c_mii); @@ -427,6 +432,12 @@ static int sfp_i2c_configure(struct sfp *sfp, struct i2c_adapter *i2c) return 0; } +static void sfp_i2c_mdiobus_destroy(struct sfp *sfp) +{ + mdiobus_unregister(sfp->i2c_mii); + sfp->i2c_mii = NULL; +} + /* Interface */ static int sfp_read(struct sfp *sfp, bool a2, u8 addr, void *buf, size_t len) { @@ -1768,6 +1779,11 @@ static int sfp_sm_mod_probe(struct sfp *sfp, bool report) else sfp->module_t_start_up = T_START_UP; + /* Configure mdiobus */ + ret = sfp_i2c_mdiobus_configure(sfp, MDIO_I2C_DEFAULT); + if (ret < 0) + return ret; + return 0; } @@ -1778,6 +1794,8 @@ static void sfp_sm_mod_remove(struct sfp *sfp) sfp_hwmon_remove(sfp); + sfp_i2c_mdiobus_destroy(sfp); + memset(&sfp->id, 0, sizeof(sfp->id)); sfp->module_power_mW = 0;
Instead of configuring the I2C mdiobus when SFP driver is probed, configure/destroy the mdiobus when SFP transceiver is plugged/unplugged. This way we can tell the mdio-i2c code which protocol to use for each SFP transceiver. Signed-off-by: Marek Behún <kabel@kernel.org> Cc: Andrew Lunn <andrew@lunn.ch> Cc: Russell King <rmk+kernel@armlinux.org.uk> --- drivers/net/phy/sfp.c | 26 ++++++++++++++++++++++---- 1 file changed, 22 insertions(+), 4 deletions(-)