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Date:   Sun, 17 Jan 2021 16:45:04 +0100
From:   Greg KH <gregkh@linuxfoundation.org>
To:     Xu Yilun <yilun.xu@intel.com>
Cc:     mdf@kernel.org, linux-fpga@vger.kernel.org,
        linux-kernel@vger.kernel.org, trix@redhat.com, lgoncalv@redhat.com,
        hao.wu@intel.com
Subject: Re: [PATCH v6 1/2] fpga: dfl: add the userspace I/O device support
 for DFL devices
Message-ID: <YARbgGU6lr3zZaKP@kroah.com>
References: <1610502848-30345-1-git-send-email-yilun.xu@intel.com>
 <1610502848-30345-2-git-send-email-yilun.xu@intel.com>
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On Wed, Jan 13, 2021 at 09:54:07AM +0800, Xu Yilun wrote:
> This patch supports the DFL drivers be written in userspace. This is
> realized by exposing the userspace I/O device interfaces.
> 
> The driver leverages the uio_pdrv_genirq, it adds the uio_pdrv_genirq
> platform device with the DFL device's resources, and let the generic UIO
> platform device driver provide support to userspace access to kernel
> interrupts and memory locations.

Why doesn't the existing uio driver work for this, why do you need a new
one?

> ---
>  drivers/fpga/Kconfig        | 10 +++++
>  drivers/fpga/Makefile       |  1 +
>  drivers/fpga/dfl-uio-pdev.c | 93 +++++++++++++++++++++++++++++++++++++++++++++

uio drivers traditionally go in drivers/uio/ and start with "uio", so
shouldn't this be drivers/uio/uio_dfl_pdev.c to match the same naming
scheme?

But again, you need to explain in detail, why the existing uio driver
doesn't work properly, or why you can't just add a few lines to an
existing one.

thanks,

greg k-h