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Date:   Wed, 24 Jul 2019 11:33:57 +0200
From:   Greg KH <gregkh@linuxfoundation.org>
To:     Wu Hao <hao.wu@intel.com>
Cc:     mdf@kernel.org, linux-fpga@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-api@vger.kernel.org,
        linux-doc@vger.kernel.org, atull@kernel.org,
        Zhang Yi Z <yi.z.zhang@intel.com>,
        Xu Yilun <yilun.xu@intel.com>
Subject: Re: [PATCH v3 02/12] fpga: dfl: fme: add
 DFL_FPGA_FME_PORT_RELEASE/ASSIGN ioctl support.
Message-ID: <20190724093357.GA29532@kroah.com>
References: <1563857495-26692-1-git-send-email-hao.wu@intel.com>
 <1563857495-26692-3-git-send-email-hao.wu@intel.com>
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On Tue, Jul 23, 2019 at 12:51:25PM +0800, Wu Hao wrote:
> +/**
> + * dfl_fpga_cdev_config_port - configure a port feature dev
> + * @cdev: parent container device.
> + * @port_id: id of the port feature device.
> + * @release: release port or assign port back.
> + *
> + * This function allows user to release port platform device or assign it back.
> + * e.g. to safely turn one port from PF into VF for PCI device SRIOV support,
> + * release port platform device is one necessary step.
> + */
> +int dfl_fpga_cdev_config_port(struct dfl_fpga_cdev *cdev, int port_id,
> +			      bool release)
> +{
> +	return release ? detach_port_dev(cdev, port_id) :
> +			 attach_port_dev(cdev, port_id);
> +}
> +EXPORT_SYMBOL_GPL(dfl_fpga_cdev_config_port);

That's a horrible api.  Every time you see this call in code, you have
to go and look up what "bool" means here.  There's no reason for it.

Just have 2 different functions, one that attaches a port, and one that
detaches it.  That way when you read the code that calls this function,
you know what it does instantly without having to go look up some api
function somewhere else.

Write code for people to read first.  And you are saving nothing here by
trying to do two different things in the same exact function.

thanks,

greg k-h