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:283: 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. 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 | 514 ++++++++++++++++ drivers/net/can/esd/esdacc.c | 777 +++++++++++++++++++++++++ drivers/net/can/esd/esdacc.h | 380 ++++++++++++ 8 files changed, 1700 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: cbe8cd7d83e251bff134a57ea4b6378db992ad82 -- 2.25.1
