From 59993f48b38fd46863b23bb1bb1dc3291e7278fb Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Thu, 8 May 2014 10:09:22 +0200 Subject: [PATCH] Revert "net: eth: cpsw: Correctly attach to GPIO bitbang MDIO driver" This reverts commit f8d56d8f892be43a2404356073e16401eb5a42e6 ("net: eth: cpsw: Correctly attach to GPIO bitbang MDIO driver"). Fix potential null-pointer dereference at probe if the mdio-gpio device has not been successfully probed yet. The offending commit is plain wrong for a number of reasons. First of all it accesses internal driver data of an unrelated device. Neither does it check that the data is non-null (which it is in case the device has not been probed yet). Furthermore, the decision on whether to treat any driver data according to the mdio-gpio driver's internals is made based on the node name. But the name is not compared against "mdio" which is the normal name for the node, but rather against "gpio" which the node does not have to be named (and shouldn't be according to the binding documentation). [ If this hack is to be kept out-of-tree it should at least be matching against the compatible property. ] Cc: Stefan Roese Cc: stable # v3.14 Signed-off-by: Johan Hovold Signed-off-by: David S. Miller --- drivers/net/ethernet/ti/cpsw.c | 14 ++------------ 1 file changed, 2 insertions(+), 12 deletions(-) diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c index 36aa109416c4..18d83d8d7f74 100644 --- a/drivers/net/ethernet/ti/cpsw.c +++ b/drivers/net/ethernet/ti/cpsw.c @@ -1871,18 +1871,8 @@ static int cpsw_probe_dt(struct cpsw_platform_data *data, mdio_node = of_find_node_by_phandle(be32_to_cpup(parp)); phyid = be32_to_cpup(parp+1); mdio = of_find_device_by_node(mdio_node); - - if (strncmp(mdio->name, "gpio", 4) == 0) { - /* GPIO bitbang MDIO driver attached */ - struct mii_bus *bus = dev_get_drvdata(&mdio->dev); - - snprintf(slave_data->phy_id, sizeof(slave_data->phy_id), - PHY_ID_FMT, bus->id, phyid); - } else { - /* davinci MDIO driver attached */ - snprintf(slave_data->phy_id, sizeof(slave_data->phy_id), - PHY_ID_FMT, mdio->name, phyid); - } + snprintf(slave_data->phy_id, sizeof(slave_data->phy_id), + PHY_ID_FMT, mdio->name, phyid); mac_addr = of_get_mac_address(slave_node); if (mac_addr) -- 2.20.1