[PATCH] net: lpc_eth: Fix crash on ip link up

[stigge@antcom.de]

From: Roland Stigge <stigge@antcom.de>

When a link is already up, the following sequence makes the kernel
block completely:

  ip link set dev eth0 down
  ip link set dev eth0 up

This is because on suspended phy, the following lines

  __lpc_eth_reset(pldat);
  __lpc_eth_init(pldat);

make the LPC ethernet core block (see LPC32x0 manual). The PHY needs to be
(re-)activated low-level first.

Signed-off-by: Roland Stigge <stigge@antcom.de>
---
 Applies to v3.17-rc3

 drivers/net/ethernet/nxp/lpc_eth.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/net/ethernet/nxp/lpc_eth.c b/drivers/net/ethernet/nxp/lpc_eth.c
index 8706c0d..a44a03c 100644
--- a/drivers/net/ethernet/nxp/lpc_eth.c
+++ b/drivers/net/ethernet/nxp/lpc_eth.c
@@ -1220,6 +1220,9 @@ static int lpc_eth_open(struct net_device *ndev)
 
 	__lpc_eth_clock_enable(pldat, true);
 
+	/* Suspended PHY makes LPC ethernet core block, so resume now */
+	phy_resume(pldat->phy_dev);
+
 	/* Reset and initialize */
 	__lpc_eth_reset(pldat);
 	__lpc_eth_init(pldat);
-- 
2.1.0