Re: [PATCH net-next] s390/net: Remove LCS driver

[Simon Horman <horms@kernel.org>]

On Tue, Feb 04, 2025 at 11:31:35AM +0100, Alexandra Winter wrote:
> From: Aswin Karuvally <aswin@linux.ibm.com>
> 
> The original Open Systems Adapter (OSA) was introduced by IBM in the
> mid-90s. These were then superseded by OSA-Express in 1999 which used
> Queued Direct IO to greatly improve throughput. The newer cards
> retained the older, slower non-QDIO (OSE) modes for compatibility with
> older systems. In Linux, the lcs driver was responsible for cards
> operating in the older OSE mode and the qeth driver was introduced to
> allow the OSA-Express cards to operate in the newer QDIO (OSD) mode.
> 
> For an S390 machine from 1998 or later, there is no reason to use the
> OSE mode and lcs driver as all OSA cards since 1999 provide the faster
> OSD mode. As a result, it's been years since we have heard of a
> customer configuration involving the lcs driver.
> 
> This patch removes the lcs driver. The technology it supports has been
> obsolete for past 25+ years and is irrelevant for current use cases.
> 
> Reviewed-by: Alexandra Winter <wintera@linux.ibm.com>
> Acked-by: Heiko Carstens <hca@linux.ibm.com>
> Acked-by: Peter Oberparleiter <oberpar@linux.ibm.com>
> Signed-off-by: Aswin Karuvally <aswin@linux.ibm.com>
> Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
> ---
>  Documentation/arch/s390/driver-model.rst |    2 +-
>  arch/s390/include/asm/irq.h              |    1 -
>  arch/s390/kernel/irq.c                   |    1 -
>  drivers/s390/net/Kconfig                 |   11 +-
>  drivers/s390/net/Makefile                |    1 -
>  drivers/s390/net/lcs.c                   | 2385 ----------------------
>  drivers/s390/net/lcs.h                   |  342 ----
>  7 files changed, 2 insertions(+), 2741 deletions(-)
>  delete mode 100644 drivers/s390/net/lcs.c
>  delete mode 100644 drivers/s390/net/lcs.h

Less is more :)

Reviewed-by: Simon Horman <horms@kernel.org>