dp83640: Ensure against premature access to PHY registers after reset

The datasheet specifies a 3uS pause after performing a software
reset. The default implementation of genphy_soft_reset() does not
provide this, so implement soft_reset with the needed pause.

Signed-off-by: Esben Haabendal <eha@deif.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Esben Haabendal 2018-04-08 22:17:01 +02:00 committed by David S. Miller
parent 1f1cba787f
commit 76327a35ca
1 changed files with 18 additions and 0 deletions

View File

@ -1207,6 +1207,23 @@ static void dp83640_remove(struct phy_device *phydev)
kfree(dp83640); kfree(dp83640);
} }
static int dp83640_soft_reset(struct phy_device *phydev)
{
int ret;
ret = genphy_soft_reset(phydev);
if (ret < 0)
return ret;
/* From DP83640 datasheet: "Software driver code must wait 3 us
* following a software reset before allowing further serial MII
* operations with the DP83640."
*/
udelay(10); /* Taking udelay inaccuracy into account */
return 0;
}
static int dp83640_config_init(struct phy_device *phydev) static int dp83640_config_init(struct phy_device *phydev)
{ {
struct dp83640_private *dp83640 = phydev->priv; struct dp83640_private *dp83640 = phydev->priv;
@ -1501,6 +1518,7 @@ static struct phy_driver dp83640_driver = {
.flags = PHY_HAS_INTERRUPT, .flags = PHY_HAS_INTERRUPT,
.probe = dp83640_probe, .probe = dp83640_probe,
.remove = dp83640_remove, .remove = dp83640_remove,
.soft_reset = dp83640_soft_reset,
.config_init = dp83640_config_init, .config_init = dp83640_config_init,
.ack_interrupt = dp83640_ack_interrupt, .ack_interrupt = dp83640_ack_interrupt,
.config_intr = dp83640_config_intr, .config_intr = dp83640_config_intr,