netdev: bfin_mac: handle timeouts with the MDIO registers gracefully
Have the low level MDIO functions pass back up timeout information so we
don't waste time polling them multiple times when there is a problem, and
so we don't let higher layers think the device is available when it isn't.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/bfin_mac.c b/drivers/net/bfin_mac.c
index 8166611..2538eaa 100644
--- a/drivers/net/bfin_mac.c
+++ b/drivers/net/bfin_mac.c
@@ -81,9 +81,6 @@
static u16 pin_req[] = P_MII0;
#endif
-static void bfin_mac_disable(void);
-static void bfin_mac_enable(void);
-
static void desc_list_free(void)
{
struct net_dma_desc_rx *r;
@@ -260,7 +257,7 @@
* MII operations
*/
/* Wait until the previous MDC/MDIO transaction has completed */
-static void bfin_mdio_poll(void)
+static int bfin_mdio_poll(void)
{
int timeout_cnt = MAX_TIMEOUT_CNT;
@@ -270,22 +267,30 @@
if (timeout_cnt-- < 0) {
printk(KERN_ERR DRV_NAME
": wait MDC/MDIO transaction to complete timeout\n");
- break;
+ return -ETIMEDOUT;
}
}
+
+ return 0;
}
/* Read an off-chip register in a PHY through the MDC/MDIO port */
static int bfin_mdiobus_read(struct mii_bus *bus, int phy_addr, int regnum)
{
- bfin_mdio_poll();
+ int ret;
+
+ ret = bfin_mdio_poll();
+ if (ret)
+ return ret;
/* read mode */
bfin_write_EMAC_STAADD(SET_PHYAD((u16) phy_addr) |
SET_REGAD((u16) regnum) |
STABUSY);
- bfin_mdio_poll();
+ ret = bfin_mdio_poll();
+ if (ret)
+ return ret;
return (int) bfin_read_EMAC_STADAT();
}
@@ -294,7 +299,11 @@
static int bfin_mdiobus_write(struct mii_bus *bus, int phy_addr, int regnum,
u16 value)
{
- bfin_mdio_poll();
+ int ret;
+
+ ret = bfin_mdio_poll();
+ if (ret)
+ return ret;
bfin_write_EMAC_STADAT((u32) value);
@@ -304,9 +313,7 @@
STAOP |
STABUSY);
- bfin_mdio_poll();
-
- return 0;
+ return bfin_mdio_poll();
}
static int bfin_mdiobus_reset(struct mii_bus *bus)
@@ -1180,8 +1187,9 @@
/*
* Enable Interrupts, Receive, and Transmit
*/
-static void bfin_mac_enable(void)
+static int bfin_mac_enable(void)
{
+ int ret;
u32 opmode;
pr_debug("%s: %s\n", DRV_NAME, __func__);
@@ -1191,7 +1199,9 @@
bfin_write_DMA1_CONFIG(rx_list_head->desc_a.config);
/* Wait MII done */
- bfin_mdio_poll();
+ ret = bfin_mdio_poll();
+ if (ret)
+ return ret;
/* We enable only RX here */
/* ASTP : Enable Automatic Pad Stripping
@@ -1215,6 +1225,8 @@
#endif
/* Turn on the EMAC rx */
bfin_write_EMAC_OPMODE(opmode);
+
+ return 0;
}
/* Our watchdog timed out. Called by the networking layer */
@@ -1327,7 +1339,7 @@
static int bfin_mac_open(struct net_device *dev)
{
struct bfin_mac_local *lp = netdev_priv(dev);
- int retval;
+ int ret;
pr_debug("%s: %s\n", dev->name, __func__);
/*
@@ -1341,18 +1353,21 @@
}
/* initial rx and tx list */
- retval = desc_list_init();
-
- if (retval)
- return retval;
+ ret = desc_list_init();
+ if (ret)
+ return ret;
phy_start(lp->phydev);
phy_write(lp->phydev, MII_BMCR, BMCR_RESET);
setup_system_regs(dev);
setup_mac_addr(dev->dev_addr);
+
bfin_mac_disable();
- bfin_mac_enable();
+ ret = bfin_mac_enable();
+ if (ret)
+ return ret;
pr_debug("hardware init finished\n");
+
netif_start_queue(dev);
netif_carrier_on(dev);