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From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
To: Bill Gatliff <bgat@billgatliff.com>
Cc: linux-input@vger.kernel.org
Subject: Re: Synchronizing evdev readers and drivers?
Date: Thu, 2 Dec 2010 13:22:24 -0800	[thread overview]
Message-ID: <20101202212223.GA9864@core.coreip.homeip.net> (raw)
In-Reply-To: <AANLkTik8X-Xe9fvYUtRObRBP1PyedOu+zwb1SKKf+kgy@mail.gmail.com>

On Thu, Dec 02, 2010 at 11:26:53AM -0600, Bill Gatliff wrote:
> Guys:
> 
> 
> Is there any  way for an input device driver (e.g. something that
> calls input_report_abs() and input_sync()) to know when there is a
> reader of its associated /dev/input/eventX?
> 
> I would love to know when something calls evdev_read() and/or
> evdev_poll(), so that I could then initiate a sampling operation on
> the hardware itself.  Otherwise, I'm forced to periodically poll the
> hardware and that means I'm either gathering data that no application
> wants,

We do not have such fine granularity as per-read. Input drivers get
notified when first application opens one of the interfaces (by
implementing input->open()). We expect that applications that open
input interfaces will read the data from them.

-- 
Dmitry

  reply	other threads:[~2010-12-02 21:22 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-12-02 17:26 Synchronizing evdev readers and drivers? Bill Gatliff
2010-12-02 21:22 ` Dmitry Torokhov [this message]
2010-12-02 21:34   ` Bill Gatliff
2010-12-03 12:42     ` Mark Brown
2010-12-03 13:03       ` Bill Gatliff
2010-12-03 13:53         ` Mark Brown
2010-12-03 17:36           ` Bill Gatliff
2010-12-03 18:52             ` Mark Brown
2010-12-03 19:41               ` Bill Gatliff
2010-12-03 22:27                 ` Mark Brown
2010-12-03 23:05                   ` Dmitry Torokhov
2010-12-03 19:50             ` Dmitry Torokhov
2010-12-03 20:17               ` Bill Gatliff
2010-12-03 21:24                 ` Dmitry Torokhov
2010-12-03 19:32     ` Dmitry Torokhov
2010-12-03 19:50       ` Bill Gatliff
2010-12-03 20:56         ` Dmitry Torokhov
2010-12-04 17:52           ` Jonathan Cameron
2010-12-04 18:15           ` Bill Gatliff
2010-12-04 17:46 ` Jonathan Cameron

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