From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Message-ID: <51DA588A.5050609@digi.com> Date: Mon, 8 Jul 2013 08:13:30 +0200 From: Hector Palacios MIME-Version: 1.0 To: CC: "linux-iio@vger.kernel.org" , "jic23@kernel.org" , Marek Vasut , "fabio.estevam@freescale.com" , "Alexandre Belloni" , Lars-Peter Clausen Subject: Reference voltages for ADC channels Content-Type: text/plain; charset="ISO-8859-1"; format=flowed List-ID: Greetings, The other day at linux-iio@vger.kernel.org we discussed the possibility of having ADC channels voltage references moved to the DT [1]. In Freescale's i.MX28 and i.MX23, at least, the CPU has 16 ADC channels some of which are dedicated to measure internal stuff, like CPU temperature and voltages. Some channels have different fixed divisors and so different reference voltages. These reference voltages (in mV) are needed to calculate the scale to show through the sysfs IIO interface, so that a user can easily compute the real measured voltage out of the sampled data. The proposed DT entry also appears at [1]. We would love to here opinions about it. [1] http://www.spinics.net/lists/linux-iio/msg08973.html Best regards, -- Hector Palacios From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hector Palacios Subject: Reference voltages for ADC channels Date: Mon, 8 Jul 2013 08:13:30 +0200 Message-ID: <51DA588A.5050609@digi.com> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit Return-path: Sender: linux-iio-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org Cc: "linux-iio-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "jic23-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org" , Marek Vasut , "fabio.estevam-KZfg59tc24xl57MIdRCFDg@public.gmane.org" , Alexandre Belloni , Lars-Peter Clausen List-Id: devicetree@vger.kernel.org Greetings, The other day at linux-iio-u79uwXL29TY76Z2rM5mHXA@public.gmane.org we discussed the possibility of having ADC channels voltage references moved to the DT [1]. In Freescale's i.MX28 and i.MX23, at least, the CPU has 16 ADC channels some of which are dedicated to measure internal stuff, like CPU temperature and voltages. Some channels have different fixed divisors and so different reference voltages. These reference voltages (in mV) are needed to calculate the scale to show through the sysfs IIO interface, so that a user can easily compute the real measured voltage out of the sampled data. The proposed DT entry also appears at [1]. We would love to here opinions about it. [1] http://www.spinics.net/lists/linux-iio/msg08973.html Best regards, -- Hector Palacios