From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jonathan Cameron Subject: Re: [PATCH v2 6/7] iio: inv_mpu6050: Reformat sample for active scan mask Date: Mon, 30 May 2016 22:42:30 +0100 Message-ID: <4EB54DBB-A77A-4BC5-8960-5CE9EB1B5DF2@kernel.org> References: <7df4b331d35e3e6a19d13ccbcb5d12f0347b660c.1463582011.git.leonard.crestez@intel.com> <14d4a757-f60a-40c0-03b4-c36d1b22d30e@kernel.org> <49c4a235-29fd-aa55-d9d2-8ead5cefd737@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <49c4a235-29fd-aa55-d9d2-8ead5cefd737-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org> Sender: linux-iio-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Crestez Dan Leonard , linux-iio-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Hartmut Knaack , Lars-Peter Clausen , Peter Meerwald-Stadler , Daniel Baluta , Ge Gao , Peter Rosin , linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Wolfram Sang , devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala List-Id: devicetree@vger.kernel.org On 30 May 2016 14:44:41 BST, Crestez Dan Leonard wrote: >On 05/29/2016 06:47 PM, Jonathan Cameron wrote: >> On 18/05/16 16:00, Crestez Dan Leonard wrote: >>> Right now it is possible to only enable some of the x/y/z channels, >for >>> example you can enable accel_z without x or y but if you actually do >>> that what you get is actually only the x channel. >>> >>> Fix this by reformatting the hardware sample to only include the >>> requested channels. >> As it stands here there is no benefit in doing this over using the >core >> demux. In fact it's considerably less efficient (fair enough that you >> are keeping it simple in the first instance). >> The patch description should make that clear. > >Why is it less efficient? All it really does is a bunch of memcpy. Not doing agglomeration of neighbouring copies (iirc) not git either set of code to hand! > >> I'd definitely like to see simple extension of that option to handle >> a callback to get the nearest scanmask that is possible (as an >alternative >> to the static scan_masks_available list.) >> >> This only gets interesting if we are dealing with the unaligned case >and for >> these parts that only kicks in I think if the slave devices have say >3 bytes in >> their data type. > >But I want to deal with the unaligned case because it's better than >introducing odd validations on slave channels. If I added an extension >to get the nearest scanmask I would have to remove it in PATCH 7. Hmm I must have misread that. Though you were only supporting 16 bit channels for aux sensors. Then for now can we give this a slightly less generic name. I am not happy enough that we want this in the core 'yet'. Easy to rename later if it makes sense. Thanks Jonathan -- Sent from my Android device with K-9 Mail. Please excuse my brevity.