Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933456AbbFWO2K (ORCPT ); Tue, 23 Jun 2015 10:28:10 -0400 Received: from mail-yk0-f182.google.com ([209.85.160.182]:36644 "EHLO mail-yk0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754741AbbFWO17 (ORCPT ); Tue, 23 Jun 2015 10:27:59 -0400 MIME-Version: 1.0 In-Reply-To: <557D6184.90105@kernel.org> References: <1432730872-14325-1-git-send-email-stefan@agner.ch> <1432730872-14325-2-git-send-email-stefan@agner.ch> <14d469dedae9de1ce519fe90401e526e@agner.ch> <557D6184.90105@kernel.org> From: Rob Herring Date: Tue, 23 Jun 2015 09:27:36 -0500 Message-ID: Subject: Re: [PATCH v5 1/2] iio: adc: vf610: implement configurable conversion modes To: Jonathan Cameron Cc: Stefan Agner , Shawn Guo , "kernel@pengutronix.de" , knaack.h@gmx.de, Lars-Peter Clausen , Peter Meerwald , Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , Fugang Duan , Sanchayan Maity , "devicetree@vger.kernel.org" , "linux-iio@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3372 Lines: 71 On Sun, Jun 14, 2015 at 6:12 AM, Jonathan Cameron wrote: > On 08/06/15 21:07, Stefan Agner wrote: >> On 2015-06-08 19:49, Rob Herring wrote: >>> On Wed, May 27, 2015 at 7:47 AM, Stefan Agner wrote: >>>> Support configurable conversion mode through sysfs. So far, the >>>> mode used was low-power, which is enabled by default now. Beside >>>> that, the modes normal and high-speed are selectable as well. >>>> >>>> Use the new device tree property which specifies the maximum ADC >>>> conversion clock frequencies. Depending on the mode used, the >>>> available resulting conversion frequency are calculated >>>> dynamically. >>>> >>>> Acked-by: Fugang Duan >>>> Signed-off-by: Stefan Agner >>>> --- >>>> Documentation/ABI/testing/sysfs-bus-iio-vf610 | 7 + >>>> .../devicetree/bindings/iio/adc/vf610-adc.txt | 9 ++ >>>> drivers/iio/adc/vf610_adc.c | 146 +++++++++++++++------ >>>> 3 files changed, 120 insertions(+), 42 deletions(-) >>>> create mode 100644 Documentation/ABI/testing/sysfs-bus-iio-vf610 >>>> >>>> diff --git a/Documentation/ABI/testing/sysfs-bus-iio-vf610 b/Documentation/ABI/testing/sysfs-bus-iio-vf610 >>>> new file mode 100644 >>>> index 0000000..ecbc1f4 >>>> --- /dev/null >>>> +++ b/Documentation/ABI/testing/sysfs-bus-iio-vf610 >>>> @@ -0,0 +1,7 @@ >>>> +What: /sys/bus/iio/devices/iio:deviceX/conversion_mode >>>> +KernelVersion: 4.2 >>>> +Contact: linux-iio@vger.kernel.org >>>> +Description: >>>> + Specifies the hardware conversion mode used. The three >>>> + available modes are "normal", "high-speed" and "low-power", >>>> + where the last is the default mode. >>>> diff --git a/Documentation/devicetree/bindings/iio/adc/vf610-adc.txt b/Documentation/devicetree/bindings/iio/adc/vf610-adc.txt >>>> index 1a4a43d..3eb40e2 100644 >>>> --- a/Documentation/devicetree/bindings/iio/adc/vf610-adc.txt >>>> +++ b/Documentation/devicetree/bindings/iio/adc/vf610-adc.txt >>>> @@ -11,6 +11,13 @@ Required properties: >>>> - clock-names: Must contain "adc", matching entry in the clocks property. >>>> - vref-supply: The regulator supply ADC reference voltage. >>>> >>>> +Recommended properties: >>>> +- fsl,adck-max-frequency: Maximum frequencies according to datasheets operating >>>> + requirements. Three values are required, depending on conversion mode: >>>> + - Frequency in normal mode (ADLPC=0, ADHSC=0) >>>> + - Frequency in high-speed mode (ADLPC=0, ADHSC=1) >>>> + - Frequency in low-power mode (ADLPC=1, ADHSC=0) >>> >>> Why is this "adck" rather than "adc"? >> >> That is the name of the clock according to the reference manual and data >> sheet. >> >>> How is this related to today's patch adding min-sample-time? >> >> It is related in that this clock is the base to calculate the sampling >> time, but otherwise not really related. Afaik, not respecting the >> maximum clock frequency is probably more a issue for the SAR part of the >> ADC. > Rob, are you happy with Stefan's responses? Yes, it is fine. Rob -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/