From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: ARC-Seal: i=1; a=rsa-sha256; t=1520093396; cv=none; d=google.com; s=arc-20160816; b=y3C2peeh5SzLqsioaC1h9h7jV/fI7U1lUdaIAtEURzjix2sTPGKtpOCZXKy+5GABVQ sDquKRjoJTlsodkJ+f3g+TDJA6dDmD/TZHQNUzduh7tk5nVJfeFIvT3QvPi02XYJR/Gq /FqF08xJjzXXRuRHEz2TjdVEBeE1wL5QqawOJi8Xe1kmf2OP9uHyLWYwp59rkBOe8Q3R 5gJA0svpMYDGSM9v7G/kE45QxsnQkW6225B3ZPfEfm7B94OOJD7kDrBSn1w3G9048yWV IFGoYsp884rLyO9Tic77DRKFUfUxjpttJOdSSh42+WnGc3sNawyenZWwVMx834chSPmb 4L5A== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=content-transfer-encoding:mime-version:references:in-reply-to:date :cc:to:from:subject:message-id:dkim-signature :arc-authentication-results; bh=+J/v1w2i+pq/P4Va9aceR3oWfG4mG/1E/3Jtyh6bvf4=; b=vPuSwiLSusbmazoXRw7RM4nXIi7nSxPLipXN8W2goARpB1FjqiHzrxcCWqC0tQ5JTp aNi/Ypuhb2lEBCIAIbRx6IBhCrZMvV72F3c0u+gQpeNYdMsRUqGWptGVC1NALMhERebs UzKwePrN+4L8a7IrWQems/YBUSP8qmCdSysyM/kOXXRKqDO/enjwNG4P13AEZ9FLkw2I 33CbL7a3Wmbamccq84SNYRKmb2nvnOUV77ewLskV3kWaAXooGGtFZi//VOdZKrCEuXP7 jq+OBL7lnNo+nIuOL8RoTdQ1lHhNQkL+guMOW8Mu4TSyR8KdYnYZcLEgygNLAhUb3Mb6 RQJQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=A2xTbr0p; spf=pass (google.com: domain of shreeya.patel23498@gmail.com designates 209.85.220.65 as permitted sender) smtp.mailfrom=shreeya.patel23498@gmail.com; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=A2xTbr0p; spf=pass (google.com: domain of shreeya.patel23498@gmail.com designates 209.85.220.65 as permitted sender) smtp.mailfrom=shreeya.patel23498@gmail.com; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com X-Google-Smtp-Source: AG47ELufGI1FwRKqQniuMCykfragvTrChqegZass5klfXPhhe1h0lBcfw3vSOn8kxxYEIe0mq5AEzQ== Message-ID: <1520091212.3137.1.camel@gmail.com> Subject: Re: [PATCH 5/6] Staging: iio: adis16209: Add some informatic comments From: Shreeya Patel To: Jonathan Cameron Cc: lars@metafoo.de, Michael.Hennerich@analog.com, knaack.h@gmx.de, pmeerw@pmeerw.net, gregkh@linuxfoundation.org, linux-iio@vger.kernel.org, devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org, daniel.baluta@gmail.com Date: Sat, 03 Mar 2018 21:03:32 +0530 In-Reply-To: <20180303160155.67113206@archlinux> References: <11a9db0dda77749c865e864c81924c0ec578dd86.1519995673.git.shreeya.patel23498@gmail.com> <20180303160155.67113206@archlinux> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.18.5.2-0ubuntu3.2 Mime-Version: 1.0 Content-Transfer-Encoding: 8bit X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1593832975858621968?= X-GMAIL-MSGID: =?utf-8?q?1593933452785406830?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: On Sat, 2018-03-03 at 16:01 +0000, Jonathan Cameron wrote: > On Fri,  2 Mar 2018 19:02:48 +0530 > Shreeya Patel wrote: > > > > > Some of the register names does not make it's puporse > > very clear and hence, add some comments for more > > information. > > Also there are certain unit based comments which are not > > providing sufficient information, so expand those comments. > Ah - serves me right for not reading on before commenting on the > previous > patch.  It would have been preferable to have merged at least some of > this > in there as they needed to be read together. > > One comment in here doesn't quite cover everything I think should > be explained. > > Please fix that and merge this down with the previous patch > (interactive rebase and marking it as a fixup makes this easy). > > Thanks, > > Jonathan > > > > > > > Signed-off-by: Shreeya Patel > > --- > >  drivers/staging/iio/accel/adis16209.c | 21 ++++++++++++++++++--- > >  1 file changed, 18 insertions(+), 3 deletions(-) > > > > diff --git a/drivers/staging/iio/accel/adis16209.c > > b/drivers/staging/iio/accel/adis16209.c > > index d2d1254..7363fd0 100644 > > --- a/drivers/staging/iio/accel/adis16209.c > > +++ b/drivers/staging/iio/accel/adis16209.c > > @@ -27,13 +27,18 @@ > >  #define ADIS16209_SUPPLY_OUT_REG 0x02 > >  #define ADIS16209_XACCL_OUT_REG 0x04 > >  #define ADIS16209_YACCL_OUT_REG 0x06 > > +/* Output, auxiliary ADC */ > >  #define ADIS16209_AUX_ADC_REG 0x08 > > +/* Output, temperature */ > >  #define ADIS16209_TEMP_OUT_REG 0x0A > > +/* Output, +/- 90 degrees X-axis inclination */ > >  #define ADIS16209_XINCL_OUT_REG 0x0C > >  #define ADIS16209_YINCL_OUT_REG 0x0E > >  #define ADIS16209_ROT_OUT_REG 0x10 > >   > > -/* Calibration Register Definitions */ > > +/* Calibration Register Definitions. > > + * Acceleration, inclination or rotation offset null. > > + */ > >  #define ADIS16209_XACCL_NULL_REG 0x12 > >  #define ADIS16209_YACCL_NULL_REG 0x14 > >  #define ADIS16209_XINCL_NULL_REG 0x16 > > @@ -155,19 +160,29 @@ static int adis16209_read_raw(struct iio_dev > > *indio_dev, > >   *val2 = 0; > >   return IIO_VAL_INT_PLUS_MICRO; > >   case IIO_ACCEL: > > + /* > > +  * IIO base unit for sensitivity of > > accelerometer > > +  * is milligram. > > +  * 1 LSB represents 0.244 milligrams. > Not miligrams. Milli g where 1 g is the 'standard' acceleration due > to gravity. Ah!! Should have used my common sense here :( Sorry for such mistake. > > > > > +  */ > >   *val = 0; > > - *val2 = IIO_G_TO_M_S_2(244140); /* > > 0.244140 mg */ > > + *val2 = IIO_G_TO_M_S_2(244140); > >   return IIO_VAL_INT_PLUS_NANO; > >   case IIO_INCLI: > >   case IIO_ROT: > > + /* > > +  * IIO base units for rotation are > > degrees. > > +  * 1 LSB represents 0.025 milli degrees. > > +  */ > >   *val = 0; > > - *val2 = 25000; /* 0.025 degree */ > > + *val2 = 25000; > >   return IIO_VAL_INT_PLUS_MICRO; > >   default: > >   return -EINVAL; > >   } > >   break; > >   case IIO_CHAN_INFO_OFFSET: > > + /* TEMP_OUT_REG has a scale factor of -0.47 > > degrees celcius. */ > This doesn't explain the magic 0x4FE so that needs doing as well. > > > > >   *val = 25000 / -470 - 0x4FE; > >   return IIO_VAL_INT; > >   case IIO_CHAN_INFO_CALIBBIAS: