| Message ID | 1691796578-846-1-git-send-email-justin.chen@broadcom.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | net: phy: broadcom: stub c45 read/write for 54810 | expand |
On 8/11/2023 4:29 PM, Justin Chen wrote: > The 54810 does not support c45. The mmd_phy_indirect accesses return > arbirtary values leading to odd behavior like saying it supports EEE > when it doesn't. We also see that reading/writing these non-existent > MMD registers leads to phy instability in some cases. > > Signed-off-by: Justin Chen <justin.chen@broadcom.com> Thanks for submitting this fix, I would be tempted to slap a: Fixes: b14995ac2527 ("net: phy: broadcom: Add BCM54810 PHY entry") so we get it back ported to stable trees where appropriate. It is not clear whether we should return -EINVAL vs. -EOPNOTSUPP which may more clearly indicate the inability to support MMD registers?
On Fri, Aug 11, 2023 at 4:40 PM Florian Fainelli <florian.fainelli@broadcom.com> wrote: > > > > On 8/11/2023 4:29 PM, Justin Chen wrote: > > The 54810 does not support c45. The mmd_phy_indirect accesses return > > arbirtary values leading to odd behavior like saying it supports EEE > > when it doesn't. We also see that reading/writing these non-existent > > MMD registers leads to phy instability in some cases. > > > > Signed-off-by: Justin Chen <justin.chen@broadcom.com> > > Thanks for submitting this fix, I would be tempted to slap a: > > Fixes: b14995ac2527 ("net: phy: broadcom: Add BCM54810 PHY entry") > > so we get it back ported to stable trees where appropriate. It is not > clear whether we should return -EINVAL vs. -EOPNOTSUPP which may more > clearly indicate the inability to support MMD registers? Hmm agreed EOPNOTSUPP seems better here. Will submit v2 with fixes tag if there are no objections to this patch. Thanks, Justin > -- > Florian
On 8/11/2023 4:47 PM, Justin Chen wrote: > On Fri, Aug 11, 2023 at 4:40 PM Florian Fainelli > <florian.fainelli@broadcom.com> wrote: >> >> >> >> On 8/11/2023 4:29 PM, Justin Chen wrote: >>> The 54810 does not support c45. The mmd_phy_indirect accesses return >>> arbirtary values leading to odd behavior like saying it supports EEE >>> when it doesn't. We also see that reading/writing these non-existent >>> MMD registers leads to phy instability in some cases. >>> >>> Signed-off-by: Justin Chen <justin.chen@broadcom.com> >> >> Thanks for submitting this fix, I would be tempted to slap a: >> >> Fixes: b14995ac2527 ("net: phy: broadcom: Add BCM54810 PHY entry") >> >> so we get it back ported to stable trees where appropriate. It is not >> clear whether we should return -EINVAL vs. -EOPNOTSUPP which may more >> clearly indicate the inability to support MMD registers? > > Hmm agreed EOPNOTSUPP seems better here. Will submit v2 with fixes tag > if there are no objections to this patch. Since this is a fix, you will want to use [PATCH net] as the subject prefix per: https://www.kernel.org/doc/Documentation/networking/netdev-FAQ.txt and wait 24hrs in case someone provides additional review that you can incorporate in your v2.
> Hmm agreed EOPNOTSUPP seems better here.
I was thinking the same.
Andrew
diff --git a/drivers/net/phy/broadcom.c b/drivers/net/phy/broadcom.c index 59cae0d808aa..8cc39427ce78 100644 --- a/drivers/net/phy/broadcom.c +++ b/drivers/net/phy/broadcom.c @@ -542,6 +542,17 @@ static int bcm54xx_resume(struct phy_device *phydev) return bcm54xx_config_init(phydev); } +static int bcm54810_read_mmd(struct phy_device *phydev, int devnum, u16 regnum) +{ + return -EINVAL; +} + +static int bcm54810_write_mmd(struct phy_device *phydev, int devnum, u16 regnum, + u16 val) +{ + return -EINVAL; +} + static int bcm54811_config_init(struct phy_device *phydev) { int err, reg; @@ -1103,6 +1114,8 @@ static struct phy_driver broadcom_drivers[] = { .get_strings = bcm_phy_get_strings, .get_stats = bcm54xx_get_stats, .probe = bcm54xx_phy_probe, + .read_mmd = bcm54810_read_mmd, + .write_mmd = bcm54810_write_mmd, .config_init = bcm54xx_config_init, .config_aneg = bcm5481_config_aneg, .config_intr = bcm_phy_config_intr,
The 54810 does not support c45. The mmd_phy_indirect accesses return arbirtary values leading to odd behavior like saying it supports EEE when it doesn't. We also see that reading/writing these non-existent MMD registers leads to phy instability in some cases. Signed-off-by: Justin Chen <justin.chen@broadcom.com> --- drivers/net/phy/broadcom.c | 13 +++++++++++++ 1 file changed, 13 insertions(+)