Re: [PATCH 1/1] MicroSemi Switchtec management interface driver

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Tue, Jan 31, 2017 at 10:03:24AM -0700, Logan Gunthorpe wrote:
> Microsemi's "Switchtec" line of PCI switch devices is already well
> supported by the kernel with standard PCI switch drivers. However, the
> Switchtec device advertises a special management endpoint with a separate
> PCI function address and class code. This endpoint enables some additional
> functionality which includes:
> 
>  * Packet and Byte Counters
>  * Switch Firmware Upgrades
>  * Event and Error logs
>  * Querying port link status
>  * Custom user firmware commands
> 
> This patch introduces the switchtec kernel module which provides
> PCI driver that exposes a char device. The char device provides
> userspace access to this interface through read, write and (optionally)
> poll calls. A couple of special IOCTLs are provided to:
> 
> * Inform userspace of firmware partition locations
> * Pass event counts and allow userspace to wait on events
> 
> A short text file is provided which documents the switchtec driver,
> outlines the semantics of using the char device and describes the
> IOCTLs.
> 
> The device also exposes a few read-only sysfs attributes which provide
> some device information component names and versions which is provided
> by the hardware. These are documented in
> Documentation/ABI/testing/sysfs-class-switchtec
> 
> A userspace tool and library which utilizes this interface is available
> at [1]. This tool takes inspiration (and borrows some code) from
> nvme-cli [2]. The tool is largely complete at this time but additional
> features may be added in the future.
> 
> [1] https://github.com/sbates130272/switchtec-user
> [2] https://github.com/linux-nvme/nvme-cli
> 
> Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
> Signed-off-by: Stephen Bates <stephen.bates@microsemi.com>
> ---
>  Documentation/ABI/testing/sysfs-class-switchtec |   96 ++
>  Documentation/ioctl/ioctl-number.txt            |    1 +
>  Documentation/switchtec.txt                     |   80 ++
>  MAINTAINERS                                     |   11 +
>  drivers/pci/Kconfig                             |    1 +
>  drivers/pci/Makefile                            |    1 +
>  drivers/pci/switch/Kconfig                      |   13 +
>  drivers/pci/switch/Makefile                     |    1 +
>  drivers/pci/switch/switchtec.c                  | 1320 +++++++++++++++++++++++
>  drivers/pci/switch/switchtec.h                  |  266 +++++

Why a .h file for a single .c file?

Also, why a whole new directory?

thanks,

greg k-h