Instead of acknowledging every item of the fifo, only acknowledge the
last item read. This behavior is documented in the datasheet. The new
getindex will be the acknowledged item + 1.
Signed-off-by: Markus Schneider-Pargmann <msp@xxxxxxxxxxxx>
---
drivers/net/can/m_can/m_can.c | 15 ++++++++++-----
1 file changed, 10 insertions(+), 5 deletions(-)
diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c
index 02fd7fe4e9f8..6179b9e815ed 100644
--- a/drivers/net/can/m_can/m_can.c
+++ b/drivers/net/can/m_can/m_can.c
@@ -530,9 +530,6 @@ static int m_can_read_fifo(struct net_device *dev, u32 fgi)
}
stats->rx_packets++;
- /* acknowledge rx fifo 0 */
- m_can_write(cdev, M_CAN_RXF0A, fgi);
-
timestamp = FIELD_GET(RX_BUF_RXTS_MASK, fifo_header.dlc) << 16;
m_can_receive_skb(cdev, skb, timestamp);
@@ -553,8 +550,9 @@ static int m_can_do_rx_poll(struct net_device *dev, int quota)
u32 rxfs;
u32 rx_count;
u32 fgi;
+ int ack_fgi = -1;
int i;
- int err;
+ int err = 0;
rxfs = m_can_read(cdev, M_CAN_RXF0S);
if (!(rxfs & RXFS_FFL_MASK)) {
@@ -568,13 +566,20 @@ static int m_can_do_rx_poll(struct net_device *dev, int quota)
for (i = 0; i < rx_count && quota > 0; ++i) {
err = m_can_read_fifo(dev, fgi);
if (err)
- return err;
+ break;
quota--;
pkts++;
+ ack_fgi = fgi;
fgi = (++fgi >= cdev->mcfg[MRAM_RXF0].num ? 0 : fgi);
}
+ if (ack_fgi != -1)
+ m_can_write(cdev, M_CAN_RXF0A, ack_fgi);
+
+ if (err)
+ return err;
+
return pkts;
}
--
2.38.1
