When switching the driver to the managed device API, I managed to break the case of a dual Ether devices sharing a single TSU: the 2nd Ether port wouldn't probe. Iwamatsu-san has tried to fix this but his patch was buggy and he then dropped the ball... The solution is to limit calling devm_request_mem_region() to the first of the two ports sharing the same TSU, so devm_ioremap_resource() can't be used anymore for the TSU resource... Fixes: d5e07e69218f ("sh_eth: use managed device API") Reported-by: Nobuhiro Iwamatsu Signed-off-by: Sergei Shtylyov --- The patch is against Dave Miller's 'net.git' repo. drivers/net/ethernet/renesas/sh_eth.c | 25 ++++++++++++++++++++++--- 1 file changed, 22 insertions(+), 3 deletions(-) Index: net/drivers/net/ethernet/renesas/sh_eth.c =================================================================== --- net.orig/drivers/net/ethernet/renesas/sh_eth.c +++ net/drivers/net/ethernet/renesas/sh_eth.c @@ -3225,10 +3225,29 @@ static int sh_eth_drv_probe(struct platf /* ioremap the TSU registers */ if (mdp->cd->tsu) { struct resource *rtsu; + rtsu = platform_get_resource(pdev, IORESOURCE_MEM, 1); - mdp->tsu_addr = devm_ioremap_resource(&pdev->dev, rtsu); - if (IS_ERR(mdp->tsu_addr)) { - ret = PTR_ERR(mdp->tsu_addr); + if (!rtsu) { + dev_err(&pdev->dev, "no TSU resource\n"); + ret = -ENODEV; + goto out_release; + } + /* We can only request the TSU region for the first port + * of the two sharing this TSU for the probe to succeed... + */ + if (devno % 2 == 0 && + !devm_request_mem_region(&pdev->dev, rtsu->start, + resource_size(rtsu), + dev_name(&pdev->dev))) { + dev_err(&pdev->dev, "can't request TSU resource.\n"); + ret = -EBUSY; + goto out_release; + } + mdp->tsu_addr = devm_ioremap(&pdev->dev, rtsu->start, + resource_size(rtsu)); + if (!mdp->tsu_addr) { + dev_err(&pdev->dev, "TSU region ioremap() failed.\n"); + ret = -ENOMEM; goto out_release; } mdp->port = devno % 2;