diff options
Diffstat (limited to 'drivers/net/phy/broadcom.c')
| -rw-r--r-- | drivers/net/phy/broadcom.c | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/drivers/net/phy/broadcom.c b/drivers/net/phy/broadcom.c index 3c683e0e40e9..e36809aa6d30 100644 --- a/drivers/net/phy/broadcom.c +++ b/drivers/net/phy/broadcom.c @@ -11,6 +11,7 @@ */ #include "bcm-phy-lib.h" +#include <linux/delay.h> #include <linux/module.h> #include <linux/phy.h> #include <linux/brcmphy.h> @@ -602,6 +603,26 @@ static int brcm_fet_config_init(struct phy_device *phydev) if (err < 0) return err; + /* The datasheet indicates the PHY needs up to 1us to complete a reset, + * build some slack here. + */ + usleep_range(1000, 2000); + + /* The PHY requires 65 MDC clock cycles to complete a write operation + * and turnaround the line properly. + * + * We ignore -EIO here as the MDIO controller (e.g.: mdio-bcm-unimac) + * may flag the lack of turn-around as a read failure. This is + * particularly true with this combination since the MDIO controller + * only used 64 MDC cycles. This is not a critical failure in this + * specific case and it has no functional impact otherwise, so we let + * that one go through. If there is a genuine bus error, the next read + * of MII_BRCM_FET_INTREG will error out. + */ + err = phy_read(phydev, MII_BMCR); + if (err < 0 && err != -EIO) + return err; + reg = phy_read(phydev, MII_BRCM_FET_INTREG); if (reg < 0) return reg; |