Re: [PATCH v5 0/2] can: esd: add support for esd GmbH PCIe/402 CAN interface

[Stefan Mätje]

Hello Marc,

there has been no feedback for the patch version v5 since a week. I had
the hope that the patch would be included in the upcoming 5.16 kernel.
The patch v5 is basically only a version v4 rebased to the linux-can-next
tree as of 2021-10-25.

The v4 version was published on the linux-can mailing list on 2021-09-16
about 8 weeks ago. Since then I had no feedback on both of these patches.

I'm not quite sure what I can do to make the inclusion process go forward.
Any information on how to proceed is appreciated.

Best regards,
    Stefan Mätje


Am Dienstag, den 09.11.2021, 16:53 +0100 schrieb Stefan Mätje:
> The purpose of this patch is to introduce a new CAN driver to support
> the esd GmbH 402 family of CAN interface boards. The hardware design
> is based on a CAN controller implemented in a FPGA attached to a
> PCIe link.
> 
> More information on these boards can be found following the links
> included in the commit message.
> 
> This patch supports all boards but will operate the CAN-FD capable
> boards only in Classic-CAN mode. The CAN-FD support will be added
> when the initial patch has stabilized.
> 
> The patch is based on the previous work of my former colleague:
> Link: https://lore.kernel.org/linux-can/1426592308-23817-1-git-send-email-thomas.koerper@xxxxxx/
> 
> *Note*: scripts/checkpatch.pl still emits the following warnings:
>   - esd_402_pci-core.c:270: Possible unnecessary 'out of memory' message
>     This error message is there to tell the user that the DMA allocation
>     failed and not an allocation for normal kernel memory.
>   - esdacc.h:255: The irq_cnt pointer is still declared volatile and
>     this has a reason and is explained in detail in the header
>     referencing the exception noted in volatile-considered-harmful.rst.
> 
> @Marc: Since v4 I've had no feedback on this patch proposal. Does this mean
> that there are no objections left and the driver now is ready for inclusion
> in the 5.16 main line kernel?
> 
> Changes in v5:
>   - Added the initialization for netdev::dev_port as it is implemented
>     for another CAN driver. See
>     https://lore.kernel.org/linux-can/20211026180553.1953189-1-mailhol.vincent@xxxxxxxxxx/
> 
> Changes in v4:
>   - Fixed the build failure on ARCH=arm64 that was found by the Intel
>     kernel test robot. See
>     https://lore.kernel.org/linux-can/202109120608.7ZbQXkRh-lkp@xxxxxxxxx/
> 
>     Removed error monitoring code that used GCC's built-in compiler
>     functions for atomic access (__sync_* functions). GCC versions
>     after 9 (tested with "gcc-10 (Ubuntu 10.3.0-1ubuntu1~20.04)")
>     don't implement the intrinsic atomic as in-line code but call
>     "__aarch64_ldadd4_acq_rel" on arm64. This GCC support function
>     is not exported by the kernel and therefore the module build
>     post-processing fails.
> 
>     Removed that code because the error monitoring never showed a
>     problem during the development this year.
> 
> 
> Changes in v3:
>   - Rework the bus-off restart logic in acc_set_mode() and
>     handle_core_msg_errstatechange() to call netif_wake_queue() from the
>     error active event.
>   - Changed pci402_init_card() to allocate a variable sized array of
>     struct acc_core using devm_kcalloc() instead of using a fixed size
>     array in struct pci402_card.
>   - Changed handle_core_msg_txabort() to release aborted TX frames in
>     TX FIFO order.
>   - Fixed the acc_close() function to abort all pending TX request in
>     esdACC controller.
>   - Fixed counting of transmit aborts in handle_core_msg_txabort().
>     It is now done like in can_flush_echo_skb().
>   - Fixed handle_core_msg_buserr() to create error frames including the
>     CAN RX and TX error counters that were missing.
>   - Fixed acc_set_bittiming() neither to touch LOM mode setting of
>     esdACC controller nor to enter or leave RESET mode.
>     The esdACC controller is going active on the CAN bus in acc_open()
>     and is going inactive (RESET mode) again in acc_close().
>   - Rely on the automatic release of memory fetched by devm_kzalloc().
>     But still use devm_irq_free() explicitely to make sure that the
>     interrupt handler is disconnected at that point.
>     This avoids a possible crash in non-MSI mode due to the IRQ
>     triggered by another device on the same PCI IRQ line.
>   - Changed to use DMA map API instead of pci_*_consistent compatibility
>     wrappers.
>   - Fixed stale email references and updated copyright information.
>   - Removed any traces of future CAN-FD support.
> 
> 
> Changes in v2:
>   - Avoid warning triggered by -Wshift-count-overflow on architectures
>     with 32-bit dma_addr_t.
>   - Fixed Makefile not to build the kernel module always. Doing this
>     renamed esd402_pci.c to esd_402_pci-core.c as recommended by Marc.
> 
> Stefan Mätje (2):
>   MAINTAINERS: add Stefan Mätje as maintainer for the esd electronics
>     GmbH CAN drivers
>   can: esd: add support for esd GmbH PCIe/402 CAN interface family
> 
>  MAINTAINERS                            |   8 +
>  drivers/net/can/Kconfig                |   1 +
>  drivers/net/can/Makefile               |   1 +
>  drivers/net/can/esd/Kconfig            |  12 +
>  drivers/net/can/esd/Makefile           |   7 +
>  drivers/net/can/esd/esd_402_pci-core.c | 502 ++++++++++++++++
>  drivers/net/can/esd/esdacc.c           | 777 +++++++++++++++++++++++++
>  drivers/net/can/esd/esdacc.h           | 380 ++++++++++++
>  8 files changed, 1688 insertions(+)
>  create mode 100644 drivers/net/can/esd/Kconfig
>  create mode 100644 drivers/net/can/esd/Makefile
>  create mode 100644 drivers/net/can/esd/esd_402_pci-core.c
>  create mode 100644 drivers/net/can/esd/esdacc.c
>  create mode 100644 drivers/net/can/esd/esdacc.h
> 
> 
> base-commit: f659c5c7de7982018bb961cf1f9960e60f526bdf