diff options
| author | Robert Foss <robert.foss@collabora.com> | 2016-08-29 16:32:18 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2016-09-01 07:07:06 +0300 |
| commit | a243c2efb5774b29f1e0b43240cfcdcabf001497 (patch) | |
| tree | 92d3a80effae6466e6ff74ef313679f34a9eebe5 | |
| parent | 4c1442aa8c2c0a2513516aeac184ea172bb04dec (diff) | |
| download | linux-a243c2efb5774b29f1e0b43240cfcdcabf001497.tar.xz | |
net: asix: see 802.3 spec for phy reset
From: Grant Grundler <grundler@chromium.org>
https://lkml.org/lkml/2014/11/11/947
Ben Hutchings is correct. IEEE 802.3 spec section "22.2.4.1.1 Reset" requires
up to 500ms delay. Mitigate the "max" delay by polling the phy until BCM_RESET
bit is clear.
Signed-off-by: Grant Grundler <grundler@chromium.org>
Signed-off-by: Robert Foss <robert.foss@collabora.com>
Tested-by: Robert Foss <robert.foss@collabora.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | drivers/net/usb/asix_devices.c | 27 |
1 files changed, 24 insertions, 3 deletions
diff --git a/drivers/net/usb/asix_devices.c b/drivers/net/usb/asix_devices.c index 083dc2ef10c8..dbcdda2ebb18 100644 --- a/drivers/net/usb/asix_devices.c +++ b/drivers/net/usb/asix_devices.c @@ -212,6 +212,28 @@ static const struct net_device_ops ax88172_netdev_ops = { .ndo_set_rx_mode = ax88172_set_multicast, }; +static void asix_phy_reset(struct usbnet *dev, unsigned int reset_bits) +{ + unsigned int timeout = 5000; + + asix_mdio_write(dev->net, dev->mii.phy_id, MII_BMCR, reset_bits); + + /* give phy_id a chance to process reset */ + udelay(500); + + /* See IEEE 802.3 "22.2.4.1.1 Reset": 500ms max */ + while (timeout--) { + if (asix_mdio_read(dev->net, dev->mii.phy_id, MII_BMCR) + & BMCR_RESET) + udelay(100); + else + return; + } + + netdev_err(dev->net, "BMCR_RESET timeout on phy_id %d\n", + dev->mii.phy_id); +} + static int ax88172_bind(struct usbnet *dev, struct usb_interface *intf) { int ret = 0; @@ -258,7 +280,7 @@ static int ax88172_bind(struct usbnet *dev, struct usb_interface *intf) dev->net->needed_headroom = 4; /* cf asix_tx_fixup() */ dev->net->needed_tailroom = 4; /* cf asix_tx_fixup() */ - asix_mdio_write(dev->net, dev->mii.phy_id, MII_BMCR, BMCR_RESET); + asix_phy_reset(dev, BMCR_RESET); asix_mdio_write(dev->net, dev->mii.phy_id, MII_ADVERTISE, ADVERTISE_ALL | ADVERTISE_CSMA | ADVERTISE_PAUSE_CAP); mii_nway_restart(&dev->mii); @@ -900,8 +922,7 @@ static int ax88178_reset(struct usbnet *dev) } else if (data->phymode == PHY_MODE_RTL8211CL) rtl8211cl_phy_init(dev); - asix_mdio_write(dev->net, dev->mii.phy_id, MII_BMCR, - BMCR_RESET | BMCR_ANENABLE); + asix_phy_reset(dev, BMCR_RESET | BMCR_ANENABLE); asix_mdio_write(dev->net, dev->mii.phy_id, MII_ADVERTISE, ADVERTISE_ALL | ADVERTISE_CSMA | ADVERTISE_PAUSE_CAP); asix_mdio_write(dev->net, dev->mii.phy_id, MII_CTRL1000, |