Tag current CAN FD controllers as non-ISO

PATCH Applied Oliver Hartkopp 2 participants 2 messages Jan 5, 2015 – Jan 7, 2015

Subsystems (2)

CAN network drivers Mcan device driver

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Oliver Hartkopp

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2015-01-05 18:47 UTC #0 lore raw

PATCH 1/1 Tag current CAN FD controllers as non-ISO

During the CAN FD standardization process within the ISO it turned out that the failure detection capability has to be improved.

The CAN in Automation organization (CiA) defined the already implemented CAN FD controllers as 'non-ISO' and the upcoming improved CAN FD controllers as 'ISO' compliant. See at http://www.can-cia.com/index.php?id=1937

Finally there will be three types of CAN FD controllers in the future:

1. ISO compliant (fixed)
2. non-ISO compliant (fixed, like the M_CAN IP v3.0.1 in m_can.c)
3. ISO/non-ISO CAN FD controllers (switchable, like the PEAK USB FD)

So the current M_CAN driver for the M_CAN IP v3.0.1 has to expose its non-ISO implementation by setting the CAN_CTRLMODE_FD_NON_ISO ctrlmode at startup. As this bit cannot be switched at configuration time CAN_CTRLMODE_FD_NON_ISO must not be set in ctrlmode_supported of the current M_CAN driver.

Signed-off-by Oliver Hartkopp <[email protected]>

---

drivers/net/can/m_can/m_can.c +5 -0

index d7bc462..2445298 100644
@@ -955,6 +955,11 @@ static struct net_device *alloc_m_can_dev(void)
 	priv->can.data_bittiming_const = &m_can_data_bittiming_const;
 	priv->can.do_set_mode = m_can_set_mode;
 	priv->can.do_get_berr_counter = m_can_get_berr_counter;
+
+	/* CAN_CTRLMODE_FD_NON_ISO is fixed with M_CAN IP v3.0.1 */
+	priv->can.ctrlmode = CAN_CTRLMODE_FD_NON_ISO;
+
+	/* CAN_CTRLMODE_FD_NON_ISO can not be changed with M_CAN IP v3.0.1 */
 	priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK |
 					CAN_CTRLMODE_LISTENONLY |
 					CAN_CTRLMODE_BERR_REPORTING |

include/uapi/linux/can/netlink.h +1 -0

index 3e4323a..94ffe0c 100644
@@ -98,6 +98,7 @@ struct can_ctrlmode {
 #define CAN_CTRLMODE_BERR_REPORTING	0x10	/* Bus-error reporting */
 #define CAN_CTRLMODE_FD			0x20	/* CAN FD mode */
 #define CAN_CTRLMODE_PRESUME_ACK	0x40	/* Ignore missing CAN ACKs */
+#define CAN_CTRLMODE_FD_NON_ISO		0x80	/* CAN FD in non-ISO mode */
 
 /*
  * CAN device statistics

Marc Kleine-Budde

maintainer Applied

2015-01-07 13:17 UTC #1 lore raw

Quoted 13 lines · Oliver Hartkopp

During the CAN FD standardization process within the ISO it turned out that the failure detection capability has to be improved.
The CAN in Automation organization (CiA) defined the already implemented CAN FD controllers as 'non-ISO' and the upcoming improved CAN FD controllers as 'ISO' compliant. See at http://www.can-cia.com/index.php?id=1937
Finally there will be three types of CAN FD controllers in the future:
1. ISO compliant (fixed)
2. non-ISO compliant (fixed, like the M_CAN IP v3.0.1 in m_can.c)
3. ISO/non-ISO CAN FD controllers (switchable, like the PEAK USB FD)

Quoted 6 lines

So the current M_CAN driver for the M_CAN IP v3.0.1 has to expose its non-ISO implementation by setting the CAN_CTRLMODE_FD_NON_ISO ctrlmode at startup. As this bit cannot be switched at configuration time CAN_CTRLMODE_FD_NON_ISO must not be set in ctrlmode_supported of the current M_CAN driver.
Signed-off-by Oliver Hartkopp <[email protected]>

Applied to can/master and added stable on Cc.

thanks,
Marc

Signature · 4 lines

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