From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Hutterer Subject: Re: [PATCH] Input: update documentation for EVIOCGMASK/EVIOCSMASK Date: Tue, 6 Sep 2016 08:14:57 +1000 Message-ID: <20160905221457.GA23405@jelly.local> References: <20160421031826.GA6719@jelly.local> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from leo.clearchain.com ([199.73.29.74]:15150 "EHLO mail.clearchain.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755239AbcIEWVu (ORCPT ); Mon, 5 Sep 2016 18:21:50 -0400 Content-Disposition: inline In-Reply-To: Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: David Herrmann Cc: linux-input@vger.kernel.org, Dmitry Torokhov , Benjamin Tissoires On Thu, Apr 21, 2016 at 10:09:11AM +0200, David Herrmann wrote: > Hi > > On Thu, Apr 21, 2016 at 5:18 AM, Peter Hutterer > wrote: > > The current implementation does not match the most intuitive reading of the > > documentation. The documentation suggests that anything after FOO_CNT would > > be reset to zeroes. The implementation however works on long boundaries > > instead. > > > > For example, a client requesting the EV_REL mask will see the first 64 bits > > set to one in the default mask, everything else is zero. Setting a mask will > > apply the mask for the first 64 bits, the others are cleared. > > > > There are few use-cases where this actually matters to a client - if a > > device doesn't have the event code anyway the mask doesn't matter. So change > > two absolute statements to a "may" to indicate that bits may or may not be > > set. > > > > Signed-off-by: Peter Hutterer > > --- > > include/uapi/linux/input.h | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > Reviewed-by: David Herrmann I just found this one on one of my branches. Dmitry, want to merge this one? Cheers, Peter > > Thanks! > David > > > diff --git a/include/uapi/linux/input.h b/include/uapi/linux/input.h > > index 0111384..6069524 100644 > > --- a/include/uapi/linux/input.h > > +++ b/include/uapi/linux/input.h > > @@ -181,7 +181,7 @@ struct input_mask { > > * The default event mask for a client has all bits set, i.e. all events > > * are forwarded to the client. If the kernel is queried for an unknown > > * event type or if the receive buffer is larger than the number of > > - * event codes known to the kernel, the kernel returns all zeroes for those > > + * event codes known to the kernel, the kernel may return zeroes for those > > * codes. > > * > > * At maximum, codes_size bytes are copied. > > @@ -204,7 +204,7 @@ struct input_mask { > > * is unknown to the kernel, or if the number of event codes specified in > > * the mask is bigger than what is known to the kernel, the ioctl is still > > * accepted and applied. However, any unknown codes are left untouched and > > - * stay cleared. That means, the kernel always filters unknown codes > > + * may be cleared. That means, the kernel always filters unknown codes > > * regardless of what the client requests. If the new mask doesn't cover > > * all known event-codes, all remaining codes are automatically cleared and > > * thus filtered. > > -- > > 2.7.3 > >