Commit graph

7 commits

Author SHA1 Message Date
Christian Pellegrin
bf66f3736a can: mcp251x: Move to threaded interrupts instead of workqueues.
This patch addresses concerns about efficiency of handling incoming
packets. Handling of interrupts is done in a threaded interrupt handler
which has a smaller latency than workqueues. This change needed a rework
of the locking scheme that was much simplified. Some other (more or less
longstanding) bugs are fixed: utilization of just half of the RX
buffers, useless wait for interrupt on open, more reliable reset
sequence. The MERR interrupt is not used anymore: it overloads the CPU
in error-passive state without any additional information. One shot mode
is disabled because it's not clear if it can be handled efficiently on
this CAN controller.

Signed-off-by: Christian Pellegrin <chripell@fsfe.org>
Acked-by: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-02-03 20:32:28 -08:00
Christian Pellegrin
ad72c347e5 can: Proper ctrlmode handling for CAN devices
This patch adds error checking of ctrlmode values for CAN devices. As
an example all availabe bits are implemented in the mcp251x driver.

Signed-off-by: Christian Pellegrin <chripell@fsfe.org>
Acked-by: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-01-15 01:39:17 -08:00
Oliver Hartkopp
3ccd4c6167 can: Unify droping of invalid tx skbs and netdev stats
To prevent the CAN drivers to operate on invalid socketbuffers the skbs are
now checked and silently dropped at the xmit-function consistently.

Also the netdev stats are consistently using the CAN data length code (dlc)
for [rx|tx]_bytes now.

Signed-off-by: Oliver Hartkopp <oliver@hartkopp.net>
Acked-by: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-01-12 02:00:46 -08:00
Julia Lawall
ce739b473c drivers/net/can: Correct NULL test
Test the just-allocated value for NULL rather than some other value.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression x,y;
statement S;
@@

x = \(kmalloc\|kcalloc\|kzalloc\)(...);
(
if ((x) == NULL) S
|
if (
-   y
+   x
       == NULL)
 S
)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Acked-by: Oliver Hartkopp <oliver@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-01-03 21:42:49 -08:00
Oliver Hartkopp
c7cd606f60 can: Fix data length code handling in rx path
A valid CAN dataframe can have a data length code (DLC) of 0 .. 8 data bytes.

When reading the CAN controllers register the 4-bit value may contain values
from 0 .. 15 which may exceed the reserved space in the socket buffer!

The ISO 11898-1 Chapter 8.4.2.3 (DLC field) says that register values > 8
should be reduced to 8 without any error reporting or frame drop.

This patch introduces a new helper macro to cast a given 4-bit data length
code (dlc) to __u8 and ensure the DLC value to be max. 8 bytes.

The different handlings in the rx path of the CAN netdevice drivers are fixed.

Signed-off-by: Oliver Hartkopp <oliver@hartkopp.net>
Signed-off-by: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-12-13 19:47:42 -08:00
Christian Pellegrin
615534bc49 can: fix setting mcp251x bit timing on open
Signed-off-by: Christian Pellegrin <chripell@fsfe.org>
Signed-off-by: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-11-18 05:03:18 -08:00
Christian Pellegrin
e0000163e3 can: Driver for the Microchip MCP251x SPI CAN controllers
Signed-off-by: Christian Pellegrin <chripell@fsfe.org>
Signed-off-by: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-11-08 01:50:21 -08:00