On 10/28/24 12:41 AM, Khoa Hoang wrote:
---- On Sun, 27 Oct 2024 07:44:59 -0700 Marek Vasut wrote ---> On 10/27/24 6:12 AM, Khoa Hoang wrote: > > In the original code, the MII_ADVERTISE register is modified while > > auto-negotiation is still in progress, which causes the PHY to lock up > > with the ASIX AX88179A. > > > > This patch disables auto-negotiation and resets the PHY before > > modifying the MII_ADVERTISE register, then restarts auto-negotiation > > afterward. This prevents the PHY from locking up. > > > > Additionally, both AX88179 and AX88179A variants do not appear to > > support the ADVERTISE_LPACK (BIT(14)) in the MII_ADVERTISE register, > > as setting this bit does not seem to have any effect. While I do not > > have access to the AX88179{,A} datasheet, in most Ethernet PHYs, this > > bit is reserved as 0, so we should avoid setting it. > > > > Signed-off-by: Khoa Hoang [email protected]> > > --- > > drivers/usb/eth/asix88179.c | 10 +++++++++- > > 1 file changed, 9 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/usb/eth/asix88179.c b/drivers/usb/eth/asix88179.c > > index 4bd3b9d1..a856aa2d 100644 > > --- a/drivers/usb/eth/asix88179.c > > +++ b/drivers/usb/eth/asix88179.c > > @@ -344,14 +344,22 @@ static int asix_basic_reset(struct ueth_data *dev, > > AX_MEDIUM_GIGAMODE | AX_MEDIUM_JUMBO_EN; > > asix_write_cmd(dev, AX_ACCESS_MAC, AX_MEDIUM_STATUS_MODE, 2, 2, tmp16); > > > > + /* Disable auto-negotiation and reset the PHY */ > > + *tmp16 = BMCR_RESET; > > Why not use the same trick as u16 adv below here ? > > u16 reset = BMCR_RESET; > asix_write_cmd(dev, AX_ACCESS_PHY, 0x03, MII_BMCR, 2, &reset); > > > + asix_write_cmd(dev, AX_ACCESS_PHY, 0x03, MII_BMCR, 2, tmp16); > > + > > u16 adv = 0; > Sure, I can apply this change. I don’t have a strong preference for one approach over the other. I noticed a mistake in these lines: + /* Restart auto-negotiation */ + *tmp16 = BMCR_ANENABLE | BMCR_ANRESTART | BMCR_RESET; + asix_write_cmd(dev, AX_ACCESS_PHY, 0x03, MII_BMCR, 2, tmp16); The issue is that I set BMCR_RESET, which would reset the PHY’s settings. This should be changed to: u16 bmcr = 0; asix_read_cmd(dev, AX_ACCESS_PHY, 0x03, MII_BMCR, 2, &bmcr); bmcr |= BMCR_ANENABLE | BMCR_ANRESTART; asix_write_cmd(dev, AX_ACCESS_PHY, 0x03, MII_BMCR, 2, tmp16); This avoids resetting the PHY settings while enabling and restarting auto-negotiation correctly. Will test this change and update in next version.
Nice !
