This patch looks wrong to me.
On 12/19/2017 09:40 AM, Luu An Phu wrote:
From: "phu.luuan" <phu.lu...@nxp.com>
flexcan_start_xmit should write data to register when can_dlc > 4.
Because can_dlc is data length and it has value from 1 to 8.
No. can_dlc can contain values from 0 to 8. Even 0 is a valid DLC.
But CAN data
index has value from 0 to 7. So in case we have data in cf->data[4],
the can_dlc has value is more than 4.
Signed-off-by: Luu An Phu <phu.lu...@nxp.com>
---
drivers/net/can/flexcan.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c
index 0626dcf..0e3ff13 100644
--- a/drivers/net/can/flexcan.c
+++ b/drivers/net/can/flexcan.c
@@ -5,6 +5,7 @@
* Copyright (c) 2009 Sascha Hauer, Pengutronix
* Copyright (c) 2010-2017 Pengutronix, Marc Kleine-Budde
<ker...@pengutronix.de>
* Copyright (c) 2014 David Jander, Protonic Holland
+ * Copyright 2017 NXP
*
* Based on code originally by Andrey Volkov <avol...@varma-el.com>
*
@@ -526,7 +527,7 @@ static int flexcan_start_xmit(struct sk_buff *skb, struct
net_device *dev)
data = be32_to_cpup((__be32 *)&cf->data[0]);
flexcan_write(data, &priv->tx_mb->data[0]);
}
- if (cf->can_dlc > 3) {
This is correct as data[0 .. 3] are filled from the code above. And if
can_dlc is greater than 3 (== 4 .. 8) the following 4 bytes are copied
into the registers.
So everything is correct with the current code.
+ if (cf->can_dlc > 4) {
data = be32_to_cpup((__be32 *)&cf->data[4]);
flexcan_write(data, &priv->tx_mb->data[1]);
}
Regards,
Oliver
