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Subject: Re: [PATCH v3] leds: Introduce userspace leds driver
To: Pavel Machek <pavel@ucw.cz>
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Cc: Jacek Anaszewski <j.anaszewski@samsung.com>,
        Richard Purdie <rpurdie@rpsys.net>, linux-kernel@vger.kernel.org,
        linux-leds@vger.kernel.org, Marcel Holtmann <marcel@holtmann.org>
From: David Lechner <david@lechnology.com>
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Date: Fri, 16 Sep 2016 10:41:20 -0500
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On 09/16/2016 01:07 AM, Pavel Machek wrote:
> Hi!
>
> +static ssize_t uleds_read(struct file *file, char __user *buffer,
> size_t count,
> + loff_t *ppos)
> +{
> + struct uleds_device *udev = file->private_data;
> + ssize_t retval;
> +
> + if (count == 0)
> + return 0;
> +
> + if (count != 1)
> + return -EINVAL;
>
> This is quite anti-social. You are free to return 1 byte on any read
> (short read), but please allow reads with bigger buffers.
>
> Thanks,
> 									Pavel
>

Sure.