From mboxrd@z Thu Jan 1 00:00:00 1970 From: Srinivas Pandruvada Subject: Re: [PATCHv2 3/3] IIO: hid-sensor-magn-3d: Add in support for True/Magnetic North HID usages Date: Wed, 04 Jun 2014 08:42:34 -0700 Message-ID: <538F3E6A.4080905@linux.intel.com> References: <1401750890-31854-1-git-send-email-reyad.attiyat@gmail.com> <1401750890-31854-4-git-send-email-reyad.attiyat@gmail.com> <538E092F.9040004@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mga02.intel.com ([134.134.136.20]:17807 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751701AbaFDPi0 (ORCPT ); Wed, 4 Jun 2014 11:38:26 -0400 In-Reply-To: Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: Reyad Attiyat Cc: linux-kernel@vger.kernel.org, linux-iio@vger.kernel.org, Jonathan Cameron , linux-input , Jiri Kosina On 06/04/2014 08:23 AM, Reyad Attiyat wrote: > Hey Srinivas, > > On Tue, Jun 3, 2014 at 12:43 PM, Srinivas Pandruvada > wrote: > >> >> May be we should have a field in const struct iio_chan_spec, so that we >> can dynamically enable disable channels. In this way we can statically >> define channels, but can be enabled/disabled dynamically. >> > Would this require changing iio subsystem to create sysfs entries only > when enabled? Would we need to add functions to disable and enable > later on? This is just a thought. You don't have to change it. I am sure Jonathan will have some opinion this. >> >> I think we need to present angle in radians. Are you basing change present >> in linux-next? This will automatically do in this function. >> > I'll look into this. What function should I use to make the iio chanel > to report radians? I think it will work if the existing sequence is maintained st->scale_precision = hid_sensor_format_scale( HID_USAGE_SENSOR_COMPASS_3D, &st->magn[CHANNEL_SCAN_INDEX_X], &st->scale_pre_decml, &st->scale_post_decml); So as long as you call this function, the scale value to user space will be returned correctly. >> >> >> I don't see kfree. Try devm_kcalloc? >> > I changed kmemdup to kcalloc so there is still a kfree in the exsiting > code. I can change this to devm_kcalloc but only if we don't go with > static channels that are enabled as found. > Since you are changing this part, devm_ calls are preferred, I think. Thanks, Srinivas > Thanks, > Reyad Attiyat >