From: Robert Marklund Date: Tue, 25 Oct 2011 22:05:43 +0000 (+0000) Subject: net/smsc911x: Always wait for the chip to be ready X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=3ac3546e;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git net/smsc911x: Always wait for the chip to be ready Wait for the chip to be ready before any access to it. On the Snowball platform we need to enable an external regulator before the chip comes online, and then it happens that the device is not yet ready at probe time, so let's wait for it. Signed-off-by: Robert Marklund Signed-off-by: Linus Walleij Signed-off-by: David S. Miller --- diff --git a/drivers/net/ethernet/smsc/smsc911x.c b/drivers/net/ethernet/smsc/smsc911x.c index d2be42aafbef..8843071fe987 100644 --- a/drivers/net/ethernet/smsc/smsc911x.c +++ b/drivers/net/ethernet/smsc/smsc911x.c @@ -1937,6 +1937,7 @@ static int __devinit smsc911x_init(struct net_device *dev) { struct smsc911x_data *pdata = netdev_priv(dev); unsigned int byte_test; + unsigned int to = 100; SMSC_TRACE(pdata, probe, "Driver Parameters:"); SMSC_TRACE(pdata, probe, "LAN base: 0x%08lX", @@ -1952,6 +1953,17 @@ static int __devinit smsc911x_init(struct net_device *dev) return -ENODEV; } + /* + * poll the READY bit in PMT_CTRL. Any other access to the device is + * forbidden while this bit isn't set. Try for 100ms + */ + while (!(smsc911x_reg_read(pdata, PMT_CTRL) & PMT_CTRL_READY_) && --to) + udelay(1000); + if (to == 0) { + pr_err("Device not READY in 100ms aborting\n"); + return -ENODEV; + } + /* Check byte ordering */ byte_test = smsc911x_reg_read(pdata, BYTE_TEST); SMSC_TRACE(pdata, probe, "BYTE_TEST: 0x%08X", byte_test);