[PATCH 2/2] can: xilinx: fix RX FIFO overflow error handling

[Michal Simek]

From: Andrea Scian <andrea.scian at dave.eu>

Simply resetting the peripheral on RX FIFO overflow in not enough,
because we also need to re-initialize the whole device.
Also always enable RX FIFO overflow interrupt otherwise we may hang
until another interrupt arrives (this happens if FIFO overrun and just
read from CAN bus with candump)

Signed-off-by: Andrea Scian <andrea.scian at dave.eu>
Reviewed-by: Kedareswara rao Appana <appanad at xilinx.com>
Signed-off-by: Michal Simek <michal.simek at xilinx.com>
---

 drivers/net/can/xilinx_can.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/net/can/xilinx_can.c b/drivers/net/can/xilinx_can.c
index 05ea2820d27b..2c119d16861e 100644
--- a/drivers/net/can/xilinx_can.c
+++ b/drivers/net/can/xilinx_can.c
@@ -101,6 +101,7 @@ enum xcan_reg {
 #define XCAN_INTR_ALL		(XCAN_IXR_TXOK_MASK | XCAN_IXR_BSOFF_MASK |\
 				 XCAN_IXR_WKUP_MASK | XCAN_IXR_SLP_MASK | \
 				 XCAN_IXR_RXNEMP_MASK | XCAN_IXR_ERROR_MASK | \
+				 XCAN_IXR_RXOFLW_MASK | \
 				 XCAN_IXR_ARBLST_MASK)
 
 /* CAN register bit shift - XCAN_<REG>_<BIT>_SHIFT */
@@ -529,6 +530,8 @@ static int xcan_rx(struct net_device *ndev)
 	return 1;
 }
 
+static void xcan_chip_stop(struct net_device *ndev);
+
 /**
  * xcan_err_interrupt - error frame Isr
  * @ndev:	net_device pointer
@@ -600,7 +603,8 @@ static void xcan_err_interrupt(struct net_device *ndev, u32 isr)
 	if (isr & XCAN_IXR_RXOFLW_MASK) {
 		stats->rx_over_errors++;
 		stats->rx_errors++;
-		priv->write_reg(priv, XCAN_SRR_OFFSET, XCAN_SRR_RESET_MASK);
+		xcan_chip_stop(ndev);
+		xcan_chip_start(ndev);
 		if (skb) {
 			cf->can_id |= CAN_ERR_CRTL;
 			cf->data[1] |= CAN_ERR_CRTL_RX_OVERFLOW;
-- 
1.9.1