Re: [PATCH v6.2 1/1] Input: Add userio module

Hi! So, I'm guessing you want me to merge this with the patch I've got
right now and post the new version? (Just making sure since I'm a bit
new to this :)

On Sat, 2015-10-24 at 15:40 -0700, Dmitry Torokhov wrote:

Hi Stephen,

On Fri, Oct 23, 2015 at 04:47:46PM -0400, cpaul@redhat.com wrote:

quoted

From: Stephen Chandler Paul <redacted>

Debugging input devices, specifically laptop touchpads, can be
tricky
without having the physical device handy. Here we try to remedy
that
with userio. This module allows an application to connect to a
character
device provided by the kernel, and emulate any serio device. In
combination with userspace programs that can record PS/2 devices
and
replay them through the /dev/userio device, this allows developers
to
debug driver issues on the PS/2 level with devices simply by
requesting
a recording from the user experiencing the issue without having to
have
the physical hardware in front of them.

Signed-off-by: Stephen Chandler Paul <redacted>
Reviewed-by: David Herrmann <redacted>
---
				    Changes
* Remove the if (!userio) { return -1; } check that somehow got
left in.

Sorry this took so long! I was wondering why you hadn't replied
yet, only to
notice I only made this change on my own tree and never sent out a
response
patch. Oops.

Thank you for making all the changes.

quoted

+
+static ssize_t userio_char_read(struct file *file, char __user
*user_buffer,
+				size_t count, loff_t *ppos)
+{
+	struct userio_device *userio = file->private_data;
+	int ret;
+	size_t nonwrap_len, copylen;
+	unsigned char buf[USERIO_BUFSIZE];
+	unsigned long flags;
+
+	if (!count)
+		return 0;

This is not quite right: read of size 0 should still check if there
is
data in the buffer and return -EAGAIN for non-blocking descriptors.

I cooked a patch (below) that should adjust the read behavior (_+ a
coupe of formatting changes), please take a look.

Thanks!

-- 
Cheers,
	Lyude