From 2bfa0f0c9a37460ee69128da411f6d310c1c983d Mon Sep 17 00:00:00 2001 From: Mike Frysinger Date: Mon, 10 May 2010 05:39:13 +0000 Subject: 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 Signed-off-by: David S. Miller --- drivers/net/bfin_mac.c | 53 ++++++++++++++++++++++++++++++++------------------ 1 file changed, 34 insertions(+), 19 deletions(-) (limited to 'drivers/net/bfin_mac.c') diff --git a/drivers/net/bfin_mac.c b/drivers/net/bfin_mac.c index 8166611f3cc..2538eaa891a 100644 --- a/drivers/net/bfin_mac.c +++ b/drivers/net/bfin_mac.c @@ -81,9 +81,6 @@ static u16 pin_req[] = P_RMII0; 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 @@ init_error: * 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 @@ static void bfin_mdio_poll(void) 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_read(struct mii_bus *bus, int phy_addr, int regnum) 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 @@ static int bfin_mdiobus_write(struct mii_bus *bus, int phy_addr, int regnum, STAOP | STABUSY); - bfin_mdio_poll(); - - return 0; + return bfin_mdio_poll(); } static int bfin_mdiobus_reset(struct mii_bus *bus) @@ -1180,8 +1187,9 @@ static void bfin_mac_disable(void) /* * 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 @@ static void bfin_mac_enable(void) 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 @@ static void bfin_mac_enable(void) #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 void bfin_mac_shutdown(struct net_device *dev) 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 @@ static int bfin_mac_open(struct net_device *dev) } /* 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); -- cgit v1.2.3