net: phy: smsc: Re-enable EDPD mode for LAN87xx

This patch re-enables Energy Detect Power Down (EDPD) mode for the
LAN8710/LAN8720.  EDPD mode was disabled in a previous commit,
(b629820d18), because it was causing the
PHY to not be able to detect a link when cold started without a cable
connected.

The LAN8710/LAN8720 requires a minimum of 2 link pulses within 64ms of
each other in order to set the ENERGYON bit and exit EDPD mode.  If a
link partner does send the pulses within this interval, the PHY will
remained powered down.

This workaround will manually toggle the PHY on/off upon calls to
read_status in order to generate link test pulses if the link is down.
If a link partner is present, it will respond to the pulses, which will
cause the ENERGYON bit to be set and will cause the EDPD mode to be
exited.

Signed-off-by: Patrick Trantham <patrick.trantham@fuel7.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Patrick Trantham 2012-11-15 09:00:57 +00:00 committed by David S. Miller
parent f191a1d17f
commit 4223dbffed
1 changed files with 45 additions and 28 deletions

View File

@ -56,37 +56,54 @@ static int smsc_phy_config_init(struct phy_device *phydev)
return smsc_phy_ack_interrupt (phydev);
}
static int lan87xx_config_init(struct phy_device *phydev)
{
/*
* Make sure the EDPWRDOWN bit is NOT set. Setting this bit on
* LAN8710/LAN8720 PHY causes the PHY to misbehave, likely due
* to a bug on the chip.
*
* When the system is powered on with the network cable being
* disconnected all the way until after ifconfig ethX up is
* issued for the LAN port with this PHY, connecting the cable
* afterwards does not cause LINK change detection, while the
* expected behavior is the Link UP being detected.
*/
int rc = phy_read(phydev, MII_LAN83C185_CTRL_STATUS);
if (rc < 0)
return rc;
rc &= ~MII_LAN83C185_EDPWRDOWN;
rc = phy_write(phydev, MII_LAN83C185_CTRL_STATUS, rc);
if (rc < 0)
return rc;
return smsc_phy_ack_interrupt(phydev);
}
static int lan911x_config_init(struct phy_device *phydev)
{
return smsc_phy_ack_interrupt(phydev);
}
/*
* The LAN8710/LAN8720 requires a minimum of 2 link pulses within 64ms of each
* other in order to set the ENERGYON bit and exit EDPD mode. If a link partner
* does send the pulses within this interval, the PHY will remained powered
* down.
*
* This workaround will manually toggle the PHY on/off upon calls to read_status
* in order to generate link test pulses if the link is down. If a link partner
* is present, it will respond to the pulses, which will cause the ENERGYON bit
* to be set and will cause the EDPD mode to be exited.
*/
static int lan87xx_read_status(struct phy_device *phydev)
{
int err = genphy_read_status(phydev);
if (!phydev->link) {
/* Disable EDPD to wake up PHY */
int rc = phy_read(phydev, MII_LAN83C185_CTRL_STATUS);
if (rc < 0)
return rc;
rc = phy_write(phydev, MII_LAN83C185_CTRL_STATUS,
rc & ~MII_LAN83C185_EDPWRDOWN);
if (rc < 0)
return rc;
/* Sleep 64 ms to allow ~5 link test pulses to be sent */
msleep(64);
/* Re-enable EDPD */
rc = phy_read(phydev, MII_LAN83C185_CTRL_STATUS);
if (rc < 0)
return rc;
rc = phy_write(phydev, MII_LAN83C185_CTRL_STATUS,
rc | MII_LAN83C185_EDPWRDOWN);
if (rc < 0)
return rc;
}
return err;
}
static struct phy_driver smsc_phy_driver[] = {
{
.phy_id = 0x0007c0a0, /* OUI=0x00800f, Model#=0x0a */
@ -187,8 +204,8 @@ static struct phy_driver smsc_phy_driver[] = {
/* basic functions */
.config_aneg = genphy_config_aneg,
.read_status = genphy_read_status,
.config_init = lan87xx_config_init,
.read_status = lan87xx_read_status,
.config_intr = smsc_phy_config_intr,
/* IRQ related */
.ack_interrupt = smsc_phy_ack_interrupt,