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63 commits

Author SHA1 Message Date
Vincent Mailhol
741b91f1b0 can: dev: can_put_echo_skb(): add software tx timestamps
Call skb_tx_timestamp() within can_put_echo_skb() so that a software tx
timestamp gets attached to the skb.

There two main reasons to include this call in can_put_echo_skb():

  * It easily allow to enable the tx timestamp on all devices with
    just one small change.

  * According to Documentation/networking/timestamping.rst, the tx
    timestamps should be generated in the device driver as close as possible,
    but always prior to passing the packet to the network interface. During the
    call to can_put_echo_skb(), the skb gets cloned meaning that the driver
    should not dereference the skb variable anymore after can_put_echo_skb()
    returns. This makes can_put_echo_skb() the very last place we can use the
    skb without having to access the echo_skb[] array.

Remark: by default, skb_tx_timestamp() does nothing. It needs to be activated
by passing the SOF_TIMESTAMPING_TX_SOFTWARE flag either through socket options
or control messages.

References:

 * Support for the error queue in CAN RAW sockets (which is needed for
   tx timestamps) was introduced in:
   https://git.kernel.org//torvalds/c/eb88531bdbfaafb827192d1fc6c5a3fcc4fadd96

  * Put the call to skb_tx_timestamp() just before adding it to the
    array:
    https://lore.kernel.org/r/043c3ea1-6bdd-59c0-0269-27b2b5b36cec@victronenergy.com

  * About Tx hardware timestamps
    https://lore.kernel.org/r/20210111171152.GB11715@hoboy.vegasvil.org

Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210112095437.6488-2-mailhol.vincent@wanadoo.fr
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-01-14 08:43:44 +01:00
Marc Kleine-Budde
99842c9685 can: dev: can_rx_offload_get_echo_skb(): extend to return can frame length
In order to implement byte queue limits (bql) in CAN drivers, the length of the
CAN frame needs to be passed into the networking stack after queueing and after
transmission completion.

To avoid to calculate this length twice, extend can_rx_offload_get_echo_skb()
to return that value. Convert all users of this function, too.

Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-15-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-01-14 08:43:43 +01:00
Marc Kleine-Budde
9420e1d495 can: dev: can_get_echo_skb(): extend to return can frame length
In order to implement byte queue limits (bql) in CAN drivers, the length of the
CAN frame needs to be passed into the networking stack after queueing and after
transmission completion.

To avoid to calculate this length twice, extend can_get_echo_skb() to return
that value. Convert all users of this function, too.

Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-14-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-01-14 08:43:43 +01:00
Vincent Mailhol
1dcb6e57db can: dev: can_put_echo_skb(): extend to handle frame_len
Add a frame_len argument to can_put_echo_skb() which is used to save length of
the CAN frame into field frame_len of struct can_skb_priv so that it can be
later used after transmission completion. Convert all users of this function,
too.

Drivers which implement BQL call can_put_echo_skb() with the output of
can_skb_get_frame_len(skb) and drivers which do not simply pass zero as an
input (in the same way that NULL would be given to can_get_echo_skb()). This
way, we have a nice symmetry between the two echo functions.

Link: https://lore.kernel.org/r/20210111061335.39983-1-mailhol.vincent@wanadoo.fr
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-13-mkl@pengutronix.de
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
2021-01-14 08:43:43 +01:00
Marc Kleine-Budde
f0ef72febc can: dev: extend struct can_skb_priv to hold CAN frame length
In order to implement byte queue limits (bql) in CAN drivers, the length of the
CAN frame needs to be passed into the networking stack after queueing and after
transmission completion.

To avoid to calculate this length twice, extend the struct can_skb_priv to hold
the length of the CAN frame and extend __can_get_echo_skb() to return that
value.

Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-12-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-01-14 08:43:42 +01:00
Vincent Mailhol
85d99c3e2a can: length: can_skb_get_frame_len(): introduce function to get data length of frame in data link layer
This patch adds the function can_skb_get_frame_len() which returns the length
of a CAN frame on the data link layer, including Start-of-frame, Identifier,
various other bits, the actual data, the CRC, the End-of-frame, the Inter frame
spacing.

Co-developed-by: Arunachalam Santhanam <arunachalam.santhanam@in.bosch.com>
Signed-off-by: Arunachalam Santhanam <arunachalam.santhanam@in.bosch.com>
Co-developed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Acked-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Co-developed-by: Marc Kleine-Budde <mkl@pengutronix.de>
Link: https://lore.kernel.org/r/20210111141930.693847-11-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-01-14 08:43:42 +01:00
Marc Kleine-Budde
652562e5ff can: length: can_fd_len2dlc(): simplify length calculcation
If the length paramter in len2dlc() exceeds the size of the len2dlc array, we
return 0xF. This is equal to the last 16 members of the array.

This patch removes these members from the array, uses ARRAY_SIZE() for the
length check, and returns CANFD_MAX_DLC (which is 0xf).

Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-9-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-01-14 08:43:41 +01:00
Marc Kleine-Budde
1ea0a52289 can: length: convert to kernel coding style
This patch converts the file into the kernel coding style.

Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-8-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-01-13 09:42:59 +01:00
Marc Kleine-Budde
0a042c6ec9 can: dev: move netlink related code into seperate file
This patch moves the netlink related code of the CAN device infrastructure into
a separate file.

Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-7-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-01-13 09:42:59 +01:00
Marc Kleine-Budde
18f2dbfd22 can: dev: move skb related into seperate file
This patch moves the skb related code of the CAN device infrastructure into a
separate file.

Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-6-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-01-13 09:42:59 +01:00
Marc Kleine-Budde
bdd2e41319 can: dev: move length related code into seperate file
This patch moves all CAN frame length related code of the CAN device
infrastructure into a separate file.

Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-5-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-01-13 09:42:59 +01:00
Marc Kleine-Budde
5a9d5ecd69 can: dev: move bittiming related code into seperate file
This patch moves the bittiming related code of the CAN device infrastructure
into a separate file.

Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-4-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-01-13 09:42:58 +01:00
Marc Kleine-Budde
3e77f70e73 can: dev: move driver related infrastructure into separate subdir
This patch moves the CAN driver related infrastructure into a separate subdir.
It will be split into more files in the coming patches.

Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-3-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-01-13 09:42:58 +01:00