From mboxrd@z Thu Jan  1 00:00:00 1970
From: Oliver Neukum <oneukum@suse.de>
Subject: Re: [PATCH v1] Input: elants_i2c: Add Elan touchscreen support
Date: Thu, 20 Nov 2014 21:27:35 +0100
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To: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: scott <scott.liu@emc.com.tw>, linux-kernel@vger.kernel.org, linux-input@vger.kernel.org, Vincent Wang <vincent.wang@emc.com.tw>, Jeff Chuang <jeff.chuang@emc.com.tw>, Benson Leung <bleung@chromium.org>, Benjamin Tissoires <benjamin.tissoires@gmail.com>, Henrik Rydberg <rydberg@euromail.se>, David Herrmann <dh.herrmann@gmail.com>

On Thu, 2014-11-20 at 09:47 -0800, Dmitry Torokhov wrote:
> Hi Oliver,
> 
> On Thu, Nov 20, 2014 at 11:31:30AM +0100, Oliver Neukum wrote:
> > > +static int elants_i2c_initialize(struct elants_data *ts)
> > > +{
> > > +       struct i2c_client *client = ts->client;
> > > +       int error, retry_cnt;
> > > +       const u8 hello_packet[] = { 0x55, 0x55, 0x55, 0x55 };
> > > +       const u8 recov_packet[] = { 0x55, 0x55, 0x80, 0x80 };
> > > +       u8 buf[HEADER_SIZE];
> > > +
> > 
> > Strictly speaking you should disable preemption here.
> 
> Umm, why?

You said the upper bound matters. So you need to protect yourself
against losing too much time by preemption.

	Regards
		Oliver