From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from saturn.retrosnub.co.uk ([178.18.118.26]:49258 "EHLO saturn.retrosnub.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751384Ab3K3MPg (ORCPT ); Sat, 30 Nov 2013 07:15:36 -0500 Message-ID: <5299D6E6.2080100@kernel.org> Date: Sat, 30 Nov 2013 12:15:34 +0000 From: Jonathan Cameron MIME-Version: 1.0 To: Maxime Ripard CC: linux-arm-kernel@lists.infradead.org, linux-iio@vger.kernel.org, Brian Lilly , Brent-Crosby , Jim Wall , Lars-Peter Clausen , Hector Palacios , Alexandre Belloni Subject: Re: [PATCH] iio: mxs-lradc: compute temperature from channel 8 and 9 References: <1384857392-2199-1-git-send-email-maxime.ripard@free-electrons.com> In-Reply-To: <1384857392-2199-1-git-send-email-maxime.ripard@free-electrons.com> Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-iio-owner@vger.kernel.org List-Id: linux-iio@vger.kernel.org On 11/19/13 10:36, Maxime Ripard wrote: > From: Alexandre Belloni > > The mxs LRADC is able to read an internal die temperature sensor. The > temperature has to be calculated from the value read on channel 8 and channel 9. > To be able to expose the result to hwmon, implement iio channel 8 as > (channel 9 - channel 8). Then, implement IIO_CHAN_INFO_SCALE and > IIO_CHAN_INFO_OFFSET so that it can be processed by hwmon through the in kernel > provider/consumer mechanism. > > Signed-off-by: Alexandre Belloni > Signed-off-by: Maxime Ripard > Reviewed-by: Lars-Peter Clausen As this is still in staging, I think we can get away with the resulting ABI change from this patch. Applied to the togreg branch of iio.git Thanks, Jonathan > --- > drivers/staging/iio/adc/mxs-lradc.c | 91 +++++++++++++++++++++++++++++++------ > 1 file changed, 78 insertions(+), 13 deletions(-) > > diff --git a/drivers/staging/iio/adc/mxs-lradc.c b/drivers/staging/iio/adc/mxs-lradc.c > index a08c1736458b..fec76090dae5 100644 > --- a/drivers/staging/iio/adc/mxs-lradc.c > +++ b/drivers/staging/iio/adc/mxs-lradc.c > @@ -231,20 +231,11 @@ struct mxs_lradc { > /* > * Raw I/O operations > */ > -static int mxs_lradc_read_raw(struct iio_dev *iio_dev, > - const struct iio_chan_spec *chan, > - int *val, int *val2, long m) > +static int mxs_lradc_read_single(struct iio_dev *iio_dev, int chan, int *val) > { > struct mxs_lradc *lradc = iio_priv(iio_dev); > int ret; > > - if (m != IIO_CHAN_INFO_RAW) > - return -EINVAL; > - > - /* Check for invalid channel */ > - if (chan->channel > LRADC_MAX_TOTAL_CHANS) > - return -EINVAL; > - > /* > * See if there is no buffered operation in progess. If there is, simply > * bail out. This can be improved to support both buffered and raw IO at > @@ -269,7 +260,7 @@ static int mxs_lradc_read_raw(struct iio_dev *iio_dev, > /* Clean the slot's previous content, then set new one. */ > writel(LRADC_CTRL4_LRADCSELECT_MASK(0), > lradc->base + LRADC_CTRL4 + STMP_OFFSET_REG_CLR); > - writel(chan->channel, lradc->base + LRADC_CTRL4 + STMP_OFFSET_REG_SET); > + writel(chan, lradc->base + LRADC_CTRL4 + STMP_OFFSET_REG_SET); > > writel(0, lradc->base + LRADC_CH(0)); > > @@ -298,6 +289,71 @@ err: > return ret; > } > > +static int mxs_lradc_read_temp(struct iio_dev *iio_dev, int *val) > +{ > + int ret, min, max; > + > + ret = mxs_lradc_read_single(iio_dev, 8, &min); > + if (ret != IIO_VAL_INT) > + return ret; > + > + ret = mxs_lradc_read_single(iio_dev, 9, &max); > + if (ret != IIO_VAL_INT) > + return ret; > + > + *val = max - min; > + > + return IIO_VAL_INT; > +} > + > +static int mxs_lradc_read_raw(struct iio_dev *iio_dev, > + const struct iio_chan_spec *chan, > + int *val, int *val2, long m) > +{ > + /* Check for invalid channel */ > + if (chan->channel > LRADC_MAX_TOTAL_CHANS) > + return -EINVAL; > + > + switch (m) { > + case IIO_CHAN_INFO_RAW: > + if (chan->type == IIO_TEMP) > + return mxs_lradc_read_temp(iio_dev, val); > + > + return mxs_lradc_read_single(iio_dev, chan->channel, val); > + > + case IIO_CHAN_INFO_SCALE: > + if (chan->type == IIO_TEMP) { > + /* From the datasheet, we have to multiply by 1.012 and > + * divide by 4 > + */ > + *val = 0; > + *val2 = 253000; > + return IIO_VAL_INT_PLUS_MICRO; > + } > + > + return -EINVAL; > + > + case IIO_CHAN_INFO_OFFSET: > + if (chan->type == IIO_TEMP) { > + /* The calculated value from the ADC is in Kelvin, we > + * want Celsius for hwmon so the offset is > + * -272.15 * scale > + */ > + *val = -1075; > + *val2 = 691699; > + > + return IIO_VAL_INT_PLUS_MICRO; > + } > + > + return -EINVAL; > + > + default: > + break; > + } > + > + return -EINVAL; > +} > + > static const struct iio_info mxs_lradc_iio_info = { > .driver_module = THIS_MODULE, > .read_raw = mxs_lradc_read_raw, > @@ -835,8 +891,17 @@ static const struct iio_chan_spec mxs_lradc_chan_spec[] = { > MXS_ADC_CHAN(5, IIO_VOLTAGE), > MXS_ADC_CHAN(6, IIO_VOLTAGE), > MXS_ADC_CHAN(7, IIO_VOLTAGE), /* VBATT */ > - MXS_ADC_CHAN(8, IIO_TEMP), /* Temp sense 0 */ > - MXS_ADC_CHAN(9, IIO_TEMP), /* Temp sense 1 */ > + /* Combined Temperature sensors */ > + { > + .type = IIO_TEMP, > + .indexed = 1, > + .scan_index = 8, > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | > + BIT(IIO_CHAN_INFO_OFFSET) | > + BIT(IIO_CHAN_INFO_SCALE), > + .channel = 8, > + .scan_type = {.sign = 'u', .realbits = 18, .storagebits = 32,}, > + }, > MXS_ADC_CHAN(10, IIO_VOLTAGE), /* VDDIO */ > MXS_ADC_CHAN(11, IIO_VOLTAGE), /* VTH */ > MXS_ADC_CHAN(12, IIO_VOLTAGE), /* VDDA */ > From mboxrd@z Thu Jan 1 00:00:00 1970 From: jic23@kernel.org (Jonathan Cameron) Date: Sat, 30 Nov 2013 12:15:34 +0000 Subject: [PATCH] iio: mxs-lradc: compute temperature from channel 8 and 9 In-Reply-To: <1384857392-2199-1-git-send-email-maxime.ripard@free-electrons.com> References: <1384857392-2199-1-git-send-email-maxime.ripard@free-electrons.com> Message-ID: <5299D6E6.2080100@kernel.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 11/19/13 10:36, Maxime Ripard wrote: > From: Alexandre Belloni > > The mxs LRADC is able to read an internal die temperature sensor. The > temperature has to be calculated from the value read on channel 8 and channel 9. > To be able to expose the result to hwmon, implement iio channel 8 as > (channel 9 - channel 8). Then, implement IIO_CHAN_INFO_SCALE and > IIO_CHAN_INFO_OFFSET so that it can be processed by hwmon through the in kernel > provider/consumer mechanism. > > Signed-off-by: Alexandre Belloni > Signed-off-by: Maxime Ripard > Reviewed-by: Lars-Peter Clausen As this is still in staging, I think we can get away with the resulting ABI change from this patch. Applied to the togreg branch of iio.git Thanks, Jonathan > --- > drivers/staging/iio/adc/mxs-lradc.c | 91 +++++++++++++++++++++++++++++++------ > 1 file changed, 78 insertions(+), 13 deletions(-) > > diff --git a/drivers/staging/iio/adc/mxs-lradc.c b/drivers/staging/iio/adc/mxs-lradc.c > index a08c1736458b..fec76090dae5 100644 > --- a/drivers/staging/iio/adc/mxs-lradc.c > +++ b/drivers/staging/iio/adc/mxs-lradc.c > @@ -231,20 +231,11 @@ struct mxs_lradc { > /* > * Raw I/O operations > */ > -static int mxs_lradc_read_raw(struct iio_dev *iio_dev, > - const struct iio_chan_spec *chan, > - int *val, int *val2, long m) > +static int mxs_lradc_read_single(struct iio_dev *iio_dev, int chan, int *val) > { > struct mxs_lradc *lradc = iio_priv(iio_dev); > int ret; > > - if (m != IIO_CHAN_INFO_RAW) > - return -EINVAL; > - > - /* Check for invalid channel */ > - if (chan->channel > LRADC_MAX_TOTAL_CHANS) > - return -EINVAL; > - > /* > * See if there is no buffered operation in progess. If there is, simply > * bail out. This can be improved to support both buffered and raw IO at > @@ -269,7 +260,7 @@ static int mxs_lradc_read_raw(struct iio_dev *iio_dev, > /* Clean the slot's previous content, then set new one. */ > writel(LRADC_CTRL4_LRADCSELECT_MASK(0), > lradc->base + LRADC_CTRL4 + STMP_OFFSET_REG_CLR); > - writel(chan->channel, lradc->base + LRADC_CTRL4 + STMP_OFFSET_REG_SET); > + writel(chan, lradc->base + LRADC_CTRL4 + STMP_OFFSET_REG_SET); > > writel(0, lradc->base + LRADC_CH(0)); > > @@ -298,6 +289,71 @@ err: > return ret; > } > > +static int mxs_lradc_read_temp(struct iio_dev *iio_dev, int *val) > +{ > + int ret, min, max; > + > + ret = mxs_lradc_read_single(iio_dev, 8, &min); > + if (ret != IIO_VAL_INT) > + return ret; > + > + ret = mxs_lradc_read_single(iio_dev, 9, &max); > + if (ret != IIO_VAL_INT) > + return ret; > + > + *val = max - min; > + > + return IIO_VAL_INT; > +} > + > +static int mxs_lradc_read_raw(struct iio_dev *iio_dev, > + const struct iio_chan_spec *chan, > + int *val, int *val2, long m) > +{ > + /* Check for invalid channel */ > + if (chan->channel > LRADC_MAX_TOTAL_CHANS) > + return -EINVAL; > + > + switch (m) { > + case IIO_CHAN_INFO_RAW: > + if (chan->type == IIO_TEMP) > + return mxs_lradc_read_temp(iio_dev, val); > + > + return mxs_lradc_read_single(iio_dev, chan->channel, val); > + > + case IIO_CHAN_INFO_SCALE: > + if (chan->type == IIO_TEMP) { > + /* From the datasheet, we have to multiply by 1.012 and > + * divide by 4 > + */ > + *val = 0; > + *val2 = 253000; > + return IIO_VAL_INT_PLUS_MICRO; > + } > + > + return -EINVAL; > + > + case IIO_CHAN_INFO_OFFSET: > + if (chan->type == IIO_TEMP) { > + /* The calculated value from the ADC is in Kelvin, we > + * want Celsius for hwmon so the offset is > + * -272.15 * scale > + */ > + *val = -1075; > + *val2 = 691699; > + > + return IIO_VAL_INT_PLUS_MICRO; > + } > + > + return -EINVAL; > + > + default: > + break; > + } > + > + return -EINVAL; > +} > + > static const struct iio_info mxs_lradc_iio_info = { > .driver_module = THIS_MODULE, > .read_raw = mxs_lradc_read_raw, > @@ -835,8 +891,17 @@ static const struct iio_chan_spec mxs_lradc_chan_spec[] = { > MXS_ADC_CHAN(5, IIO_VOLTAGE), > MXS_ADC_CHAN(6, IIO_VOLTAGE), > MXS_ADC_CHAN(7, IIO_VOLTAGE), /* VBATT */ > - MXS_ADC_CHAN(8, IIO_TEMP), /* Temp sense 0 */ > - MXS_ADC_CHAN(9, IIO_TEMP), /* Temp sense 1 */ > + /* Combined Temperature sensors */ > + { > + .type = IIO_TEMP, > + .indexed = 1, > + .scan_index = 8, > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | > + BIT(IIO_CHAN_INFO_OFFSET) | > + BIT(IIO_CHAN_INFO_SCALE), > + .channel = 8, > + .scan_type = {.sign = 'u', .realbits = 18, .storagebits = 32,}, > + }, > MXS_ADC_CHAN(10, IIO_VOLTAGE), /* VDDIO */ > MXS_ADC_CHAN(11, IIO_VOLTAGE), /* VTH */ > MXS_ADC_CHAN(12, IIO_VOLTAGE), /* VDDA */ >