From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jonathan Cameron Subject: Re: [PATCH 2/2] iio: adc: Add driver for the TI ADS8344 A/DC chips Date: Sat, 16 Mar 2019 17:06:30 +0000 Message-ID: <20190316170630.18ab5970@archlinux> References: <20190315151152.30467-1-gregory.clement@bootlin.com> <20190315151152.30467-3-gregory.clement@bootlin.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20190315151152.30467-3-gregory.clement@bootlin.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: Gregory CLEMENT Cc: devicetree@vger.kernel.org, Alexandre Belloni , Lars-Peter Clausen , Thomas Petazzoni , linux-iio@vger.kernel.org, Rob Herring , Peter Meerwald-Stadler , Hartmut Knaack , linux-arm-kernel@lists.infradead.org List-Id: devicetree@vger.kernel.org On Fri, 15 Mar 2019 16:11:51 +0100 Gregory CLEMENT wrote: > This adds support for the Texas Instruments ADS8344 ADC chip. This chip > has a 16-bit 8-Channel ADC and is access directly through SPI. > > Signed-off-by: Gregory CLEMENT Hi Gregory, A few minor bits and pieces inline. Some of them due I would guess to cut and paste from a driver where things were slightly different! If we were late in the cycle this lot would probably have been small enough that I'd just have reworked it whilst applying, but we are really early, hence you get to tidy them up ;) Thanks, Jonathan > --- > drivers/iio/adc/Kconfig | 10 ++ > drivers/iio/adc/Makefile | 1 + > drivers/iio/adc/ti-ads8344.c | 216 +++++++++++++++++++++++++++++++++++ > 3 files changed, 227 insertions(+) > create mode 100644 drivers/iio/adc/ti-ads8344.c > > diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig > index 76db6e5cc296..447d3a871746 100644 > --- a/drivers/iio/adc/Kconfig > +++ b/drivers/iio/adc/Kconfig > @@ -967,6 +967,16 @@ config TI_ADS7950 > To compile this driver as a module, choose M here: the > module will be called ti-ads7950. > > +config TI_ADS8344 > + tristate "Texas Instruments ADS8344" > + depends on SPI && OF > + help > + If you say yes here you get support for Texas Instruments ADS8344 > + ADC chips > + > + This driver can also be built as a module. If so, the module will be > + called ti-ads8344. > + > config TI_ADS8688 > tristate "Texas Instruments ADS8688" > depends on SPI && OF > diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile > index 6fcebd167524..1f3ae934111d 100644 > --- a/drivers/iio/adc/Makefile > +++ b/drivers/iio/adc/Makefile > @@ -87,6 +87,7 @@ obj-$(CONFIG_TI_ADC128S052) += ti-adc128s052.o > obj-$(CONFIG_TI_ADC161S626) += ti-adc161s626.o > obj-$(CONFIG_TI_ADS1015) += ti-ads1015.o > obj-$(CONFIG_TI_ADS7950) += ti-ads7950.o > +obj-$(CONFIG_TI_ADS8344) += ti-ads8344.o > obj-$(CONFIG_TI_ADS8688) += ti-ads8688.o > obj-$(CONFIG_TI_ADS124S08) += ti-ads124s08.o > obj-$(CONFIG_TI_AM335X_ADC) += ti_am335x_adc.o > diff --git a/drivers/iio/adc/ti-ads8344.c b/drivers/iio/adc/ti-ads8344.c > new file mode 100644 > index 000000000000..6159d8518871 > --- /dev/null > +++ b/drivers/iio/adc/ti-ads8344.c > @@ -0,0 +1,216 @@ > +// SPDX-License-Identifier: GPL-2.0+ > +/* > + * ADS8344 16-bit 8-Channel ADC driver > + * > + * Author: Gregory CLEMENT > + * > + * Datasheet: http://www.ti.com/lit/ds/symlink/ads8344.pdf > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > + > +struct ads8344 { > + struct spi_device *spi; > + struct regulator *reg; > + struct mutex lock; > + > + u8 tx_buf ____cacheline_aligned; > + u16 rx_buf; > +}; > + > +#define ADS8344_VOLTAGE_CHANNEL(chan, si) \ > + { \ > + .type = IIO_VOLTAGE, \ > + .indexed = 1, \ > + .channel = chan, \ > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ > + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ > + .scan_index = si, \ > + .scan_type = { \ You aren't currently providing a buffer, so please drop scan_index and scan_type until you are. The code won't do anything with them at the moment. > + .sign = 'u', \ > + .realbits = 16, \ > + .storagebits = 16, \ > + }, \ > + } > + > +#define ADS8344_VOLTAGE_CHANNEL_DIFF(chan1, chan2, si) \ > + { \ > + .type = IIO_VOLTAGE, \ > + .indexed = 1, \ > + .channel = (chan1), \ > + .channel2 = (chan2), \ > + .differential = 1, \ > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ > + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ > + .scan_index = si, \ > + .scan_type = { \ > + .sign = 'u', \ > + .realbits = 16, \ > + .storagebits = 16, \ > + }, \ > + } > + > +static const struct iio_chan_spec ads8344_channels[] = { > + ADS8344_VOLTAGE_CHANNEL(0, 0), > + ADS8344_VOLTAGE_CHANNEL(1, 4), > + ADS8344_VOLTAGE_CHANNEL(2, 1), > + ADS8344_VOLTAGE_CHANNEL(3, 5), > + ADS8344_VOLTAGE_CHANNEL(4, 2), > + ADS8344_VOLTAGE_CHANNEL(5, 6), > + ADS8344_VOLTAGE_CHANNEL(6, 3), > + ADS8344_VOLTAGE_CHANNEL(7, 7), > + ADS8344_VOLTAGE_CHANNEL_DIFF(0, 1, 8), > + ADS8344_VOLTAGE_CHANNEL_DIFF(2, 3, 9), > + ADS8344_VOLTAGE_CHANNEL_DIFF(4, 5, 10), > + ADS8344_VOLTAGE_CHANNEL_DIFF(6, 7, 11), > + ADS8344_VOLTAGE_CHANNEL_DIFF(1, 0, 12), > + ADS8344_VOLTAGE_CHANNEL_DIFF(3, 2, 13), > + ADS8344_VOLTAGE_CHANNEL_DIFF(5, 4, 14), > + ADS8344_VOLTAGE_CHANNEL_DIFF(7, 6, 15), > +}; > + > +static int ads8344_adc_conversion(struct ads8344 *adc, int channel, > + bool differential) > +{ > + struct spi_device *spi = adc->spi; > + int ret; > + > + /* start bit */ > + adc->tx_buf = BIT(7); > + /* single-ended or differential */ > + adc->tx_buf |= differential ? 0 : BIT(2); > + /* select channel(s) */ The moment you need comments to say what a bit is, you are almost always better off adding some defines so that this block becomes something like. adc->tx_buff = ADS8344_START; if (!differential) adc->tx_buff |= ADS8344_SINGLE_END; adc->tx_buff |= ADS8344_CHANNEL(channel); adc->tx_buff |= ADS8344_CLOCK_INTERNAL; Then you can drop the comments and the defines are nice and easy to check against a datasheet as they are all in one place. > + adc->tx_buf |= channel << 4; > + /* internal clock mode */ > + adc->tx_buf |= 0x2; > + > + ret = spi_write(spi, &adc->tx_buf, 1); > + if (ret) > + return ret; > + > + udelay(9); > + > + ret = spi_read(spi, &adc->rx_buf, 2); > + if (ret) > + return ret; > + > + return adc->rx_buf; > +} > + > +static int ads8344_read_raw(struct iio_dev *iio, > + struct iio_chan_spec const *channel, int *value, > + int *shift, long mask) > +{ > + struct ads8344 *adc = iio_priv(iio); > + > + switch (mask) { > + case IIO_CHAN_INFO_RAW: > + mutex_lock(&adc->lock); > + *value = ads8344_adc_conversion(adc, channel->scan_index, > + channel->differential); > + mutex_unlock(&adc->lock); > + if (*value < 0) > + return *value; > + > + return IIO_VAL_INT; > + case IIO_CHAN_INFO_SCALE: > + *value = regulator_get_voltage(adc->reg); > + if (*value < 0) > + return *value; > + > + /* convert regulator output voltage to mV */ > + *value /= 1000; > + *shift = 16; > + > + return IIO_VAL_FRACTIONAL_LOG2; > + default: > + return -EINVAL; > + } > +} > + > +static const struct iio_info ads8344_info = { > + .read_raw = ads8344_read_raw, > +}; > + > +static int ads8344_probe(struct spi_device *spi) > +{ > + struct iio_dev *indio_dev; > + struct ads8344 *adc; > + int ret; > + > + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*adc)); > + if (!indio_dev) > + return -ENOMEM; > + > + adc = iio_priv(indio_dev); > + adc->spi = spi; > + mutex_init(&adc->lock); > + > + indio_dev->name = dev_name(&spi->dev); > + indio_dev->dev.parent = &spi->dev; > + indio_dev->dev.of_node = spi->dev.of_node; > + indio_dev->info = &ads8344_info; > + indio_dev->modes = INDIO_DIRECT_MODE; > + indio_dev->channels = ads8344_channels; > + indio_dev->num_channels = ARRAY_SIZE(ads8344_channels); > + > + adc->reg = devm_regulator_get(&spi->dev, "vref"); > + if (IS_ERR(adc->reg)) > + return PTR_ERR(adc->reg); > + > + ret = regulator_enable(adc->reg); > + if (ret) > + return ret; > + > + spi_set_drvdata(spi, indio_dev); > + > + ret = iio_device_register(indio_dev); > + if (ret) > + goto err_buffer_cleanup; > + > + return 0; > +err_buffer_cleanup: That is not a useful or correct label.. Give it a better name! > + regulator_disable(adc->reg); > + > + return ret; > +} > + > +static int ads8344_remove(struct spi_device *spi) > +{ > + struct iio_dev *indio_dev = spi_get_drvdata(spi); > + struct ads8344 *adc = iio_priv(indio_dev); > + > + iio_device_unregister(indio_dev); > + regulator_disable(adc->reg); > + > + return 0; > +} > + > +#ifdef CONFIG_OF Given there isn't currently any other way of (normally at least) instantiating this I wouldn't bother with the config guards. Also see below for additional comment on this. > + > +static const struct of_device_id ads8344_dt_ids[] = { > + { .compatible = "ti,ads8344", }, > + {} > +}; > +MODULE_DEVICE_TABLE(of, ads8344_dt_ids); > + > +#endif > + > +static struct spi_driver ads8344_driver = { > + .driver = { > + .name = "ads8344", > + .of_match_table = of_match_ptr(ads8344_dt_ids), Don't use of_match_ptr as it breaks the magic ACPI binding which uses the DT tables. > + }, > + .probe = ads8344_probe, > + .remove = ads8344_remove, > +}; > +module_spi_driver(ads8344_driver); > + > +MODULE_AUTHOR("Gregory CLEMENT "); > +MODULE_DESCRIPTION("ADS8344 driver"); > +MODULE_LICENSE("GPL v2"); From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 93921C10F0C for ; Sat, 16 Mar 2019 17:06:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 65C6621903 for ; Sat, 16 Mar 2019 17:06:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1552756002; bh=h3bu4jNOS0uOKLx0UOwrKkfVKdFvnUOM8ki1U4PdwRc=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=R+VgBxIrEzleJFU0Ez3Kz9vCeb4R/5OgR6LpDOmqoUemL8ocVkUvmMOpNs8jL1GYt +WGamKPNiCjOUPxehzIfM8ROSbyD4KF28c653c8Y5ksT57Ss1ZFWc0KUQ01pEuBazU 2PmJKaIbq0nA1weuUK/Tqc8jv2Zpg3Udru4jYdls= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726972AbfCPRGi (ORCPT ); Sat, 16 Mar 2019 13:06:38 -0400 Received: from mail.kernel.org ([198.145.29.99]:48508 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726698AbfCPRGh (ORCPT ); Sat, 16 Mar 2019 13:06:37 -0400 Received: from archlinux (cpc91196-cmbg18-2-0-cust659.5-4.cable.virginm.net [81.96.234.148]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 0409F2186A; Sat, 16 Mar 2019 17:06:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1552755996; bh=h3bu4jNOS0uOKLx0UOwrKkfVKdFvnUOM8ki1U4PdwRc=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=ORHJfEAEuW0ZGZekby7nf+KgyNVV+Y/VZ4Ln2VnmnHzZlqBRiPpjr9opSk9F8FNJm 8s6iyZCwWmG3ltcmCl9xl+zttXHJ+UkSDc3LMvLCiV0LE3xl4LBDVEKXyRP5q9cc/O ow2tM1gDyQeQHaP2rd9rPoACuF8pDhis3Z6fMFPk= Date: Sat, 16 Mar 2019 17:06:30 +0000 From: Jonathan Cameron To: Gregory CLEMENT Cc: Hartmut Knaack , Lars-Peter Clausen , Peter Meerwald-Stadler , linux-iio@vger.kernel.org, Rob Herring , devicetree@vger.kernel.org, Thomas Petazzoni , linux-arm-kernel@lists.infradead.org, Alexandre Belloni Subject: Re: [PATCH 2/2] iio: adc: Add driver for the TI ADS8344 A/DC chips Message-ID: <20190316170630.18ab5970@archlinux> In-Reply-To: <20190315151152.30467-3-gregory.clement@bootlin.com> References: <20190315151152.30467-1-gregory.clement@bootlin.com> <20190315151152.30467-3-gregory.clement@bootlin.com> X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-iio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org On Fri, 15 Mar 2019 16:11:51 +0100 Gregory CLEMENT wrote: > This adds support for the Texas Instruments ADS8344 ADC chip. This chip > has a 16-bit 8-Channel ADC and is access directly through SPI. > > Signed-off-by: Gregory CLEMENT Hi Gregory, A few minor bits and pieces inline. Some of them due I would guess to cut and paste from a driver where things were slightly different! If we were late in the cycle this lot would probably have been small enough that I'd just have reworked it whilst applying, but we are really early, hence you get to tidy them up ;) Thanks, Jonathan > --- > drivers/iio/adc/Kconfig | 10 ++ > drivers/iio/adc/Makefile | 1 + > drivers/iio/adc/ti-ads8344.c | 216 +++++++++++++++++++++++++++++++++++ > 3 files changed, 227 insertions(+) > create mode 100644 drivers/iio/adc/ti-ads8344.c > > diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig > index 76db6e5cc296..447d3a871746 100644 > --- a/drivers/iio/adc/Kconfig > +++ b/drivers/iio/adc/Kconfig > @@ -967,6 +967,16 @@ config TI_ADS7950 > To compile this driver as a module, choose M here: the > module will be called ti-ads7950. > > +config TI_ADS8344 > + tristate "Texas Instruments ADS8344" > + depends on SPI && OF > + help > + If you say yes here you get support for Texas Instruments ADS8344 > + ADC chips > + > + This driver can also be built as a module. If so, the module will be > + called ti-ads8344. > + > config TI_ADS8688 > tristate "Texas Instruments ADS8688" > depends on SPI && OF > diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile > index 6fcebd167524..1f3ae934111d 100644 > --- a/drivers/iio/adc/Makefile > +++ b/drivers/iio/adc/Makefile > @@ -87,6 +87,7 @@ obj-$(CONFIG_TI_ADC128S052) += ti-adc128s052.o > obj-$(CONFIG_TI_ADC161S626) += ti-adc161s626.o > obj-$(CONFIG_TI_ADS1015) += ti-ads1015.o > obj-$(CONFIG_TI_ADS7950) += ti-ads7950.o > +obj-$(CONFIG_TI_ADS8344) += ti-ads8344.o > obj-$(CONFIG_TI_ADS8688) += ti-ads8688.o > obj-$(CONFIG_TI_ADS124S08) += ti-ads124s08.o > obj-$(CONFIG_TI_AM335X_ADC) += ti_am335x_adc.o > diff --git a/drivers/iio/adc/ti-ads8344.c b/drivers/iio/adc/ti-ads8344.c > new file mode 100644 > index 000000000000..6159d8518871 > --- /dev/null > +++ b/drivers/iio/adc/ti-ads8344.c > @@ -0,0 +1,216 @@ > +// SPDX-License-Identifier: GPL-2.0+ > +/* > + * ADS8344 16-bit 8-Channel ADC driver > + * > + * Author: Gregory CLEMENT > + * > + * Datasheet: http://www.ti.com/lit/ds/symlink/ads8344.pdf > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > + > +struct ads8344 { > + struct spi_device *spi; > + struct regulator *reg; > + struct mutex lock; > + > + u8 tx_buf ____cacheline_aligned; > + u16 rx_buf; > +}; > + > +#define ADS8344_VOLTAGE_CHANNEL(chan, si) \ > + { \ > + .type = IIO_VOLTAGE, \ > + .indexed = 1, \ > + .channel = chan, \ > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ > + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ > + .scan_index = si, \ > + .scan_type = { \ You aren't currently providing a buffer, so please drop scan_index and scan_type until you are. The code won't do anything with them at the moment. > + .sign = 'u', \ > + .realbits = 16, \ > + .storagebits = 16, \ > + }, \ > + } > + > +#define ADS8344_VOLTAGE_CHANNEL_DIFF(chan1, chan2, si) \ > + { \ > + .type = IIO_VOLTAGE, \ > + .indexed = 1, \ > + .channel = (chan1), \ > + .channel2 = (chan2), \ > + .differential = 1, \ > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ > + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ > + .scan_index = si, \ > + .scan_type = { \ > + .sign = 'u', \ > + .realbits = 16, \ > + .storagebits = 16, \ > + }, \ > + } > + > +static const struct iio_chan_spec ads8344_channels[] = { > + ADS8344_VOLTAGE_CHANNEL(0, 0), > + ADS8344_VOLTAGE_CHANNEL(1, 4), > + ADS8344_VOLTAGE_CHANNEL(2, 1), > + ADS8344_VOLTAGE_CHANNEL(3, 5), > + ADS8344_VOLTAGE_CHANNEL(4, 2), > + ADS8344_VOLTAGE_CHANNEL(5, 6), > + ADS8344_VOLTAGE_CHANNEL(6, 3), > + ADS8344_VOLTAGE_CHANNEL(7, 7), > + ADS8344_VOLTAGE_CHANNEL_DIFF(0, 1, 8), > + ADS8344_VOLTAGE_CHANNEL_DIFF(2, 3, 9), > + ADS8344_VOLTAGE_CHANNEL_DIFF(4, 5, 10), > + ADS8344_VOLTAGE_CHANNEL_DIFF(6, 7, 11), > + ADS8344_VOLTAGE_CHANNEL_DIFF(1, 0, 12), > + ADS8344_VOLTAGE_CHANNEL_DIFF(3, 2, 13), > + ADS8344_VOLTAGE_CHANNEL_DIFF(5, 4, 14), > + ADS8344_VOLTAGE_CHANNEL_DIFF(7, 6, 15), > +}; > + > +static int ads8344_adc_conversion(struct ads8344 *adc, int channel, > + bool differential) > +{ > + struct spi_device *spi = adc->spi; > + int ret; > + > + /* start bit */ > + adc->tx_buf = BIT(7); > + /* single-ended or differential */ > + adc->tx_buf |= differential ? 0 : BIT(2); > + /* select channel(s) */ The moment you need comments to say what a bit is, you are almost always better off adding some defines so that this block becomes something like. adc->tx_buff = ADS8344_START; if (!differential) adc->tx_buff |= ADS8344_SINGLE_END; adc->tx_buff |= ADS8344_CHANNEL(channel); adc->tx_buff |= ADS8344_CLOCK_INTERNAL; Then you can drop the comments and the defines are nice and easy to check against a datasheet as they are all in one place. > + adc->tx_buf |= channel << 4; > + /* internal clock mode */ > + adc->tx_buf |= 0x2; > + > + ret = spi_write(spi, &adc->tx_buf, 1); > + if (ret) > + return ret; > + > + udelay(9); > + > + ret = spi_read(spi, &adc->rx_buf, 2); > + if (ret) > + return ret; > + > + return adc->rx_buf; > +} > + > +static int ads8344_read_raw(struct iio_dev *iio, > + struct iio_chan_spec const *channel, int *value, > + int *shift, long mask) > +{ > + struct ads8344 *adc = iio_priv(iio); > + > + switch (mask) { > + case IIO_CHAN_INFO_RAW: > + mutex_lock(&adc->lock); > + *value = ads8344_adc_conversion(adc, channel->scan_index, > + channel->differential); > + mutex_unlock(&adc->lock); > + if (*value < 0) > + return *value; > + > + return IIO_VAL_INT; > + case IIO_CHAN_INFO_SCALE: > + *value = regulator_get_voltage(adc->reg); > + if (*value < 0) > + return *value; > + > + /* convert regulator output voltage to mV */ > + *value /= 1000; > + *shift = 16; > + > + return IIO_VAL_FRACTIONAL_LOG2; > + default: > + return -EINVAL; > + } > +} > + > +static const struct iio_info ads8344_info = { > + .read_raw = ads8344_read_raw, > +}; > + > +static int ads8344_probe(struct spi_device *spi) > +{ > + struct iio_dev *indio_dev; > + struct ads8344 *adc; > + int ret; > + > + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*adc)); > + if (!indio_dev) > + return -ENOMEM; > + > + adc = iio_priv(indio_dev); > + adc->spi = spi; > + mutex_init(&adc->lock); > + > + indio_dev->name = dev_name(&spi->dev); > + indio_dev->dev.parent = &spi->dev; > + indio_dev->dev.of_node = spi->dev.of_node; > + indio_dev->info = &ads8344_info; > + indio_dev->modes = INDIO_DIRECT_MODE; > + indio_dev->channels = ads8344_channels; > + indio_dev->num_channels = ARRAY_SIZE(ads8344_channels); > + > + adc->reg = devm_regulator_get(&spi->dev, "vref"); > + if (IS_ERR(adc->reg)) > + return PTR_ERR(adc->reg); > + > + ret = regulator_enable(adc->reg); > + if (ret) > + return ret; > + > + spi_set_drvdata(spi, indio_dev); > + > + ret = iio_device_register(indio_dev); > + if (ret) > + goto err_buffer_cleanup; > + > + return 0; > +err_buffer_cleanup: That is not a useful or correct label.. Give it a better name! > + regulator_disable(adc->reg); > + > + return ret; > +} > + > +static int ads8344_remove(struct spi_device *spi) > +{ > + struct iio_dev *indio_dev = spi_get_drvdata(spi); > + struct ads8344 *adc = iio_priv(indio_dev); > + > + iio_device_unregister(indio_dev); > + regulator_disable(adc->reg); > + > + return 0; > +} > + > +#ifdef CONFIG_OF Given there isn't currently any other way of (normally at least) instantiating this I wouldn't bother with the config guards. Also see below for additional comment on this. > + > +static const struct of_device_id ads8344_dt_ids[] = { > + { .compatible = "ti,ads8344", }, > + {} > +}; > +MODULE_DEVICE_TABLE(of, ads8344_dt_ids); > + > +#endif > + > +static struct spi_driver ads8344_driver = { > + .driver = { > + .name = "ads8344", > + .of_match_table = of_match_ptr(ads8344_dt_ids), Don't use of_match_ptr as it breaks the magic ACPI binding which uses the DT tables. > + }, > + .probe = ads8344_probe, > + .remove = ads8344_remove, > +}; > +module_spi_driver(ads8344_driver); > + > +MODULE_AUTHOR("Gregory CLEMENT "); > +MODULE_DESCRIPTION("ADS8344 driver"); > +MODULE_LICENSE("GPL v2"); From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS, URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3D984C43381 for ; Sat, 16 Mar 2019 17:06:53 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 0C9D6218D0 for ; Sat, 16 Mar 2019 17:06:52 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="RiemfSqV"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="ORHJfEAE" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0C9D6218D0 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=5JUI5todlb5QgIzJWNiKQgDwUbj6gTAdvKbQ5oQpJPA=; b=RiemfSqVMpYJps 2f62hBrez+5Hr2vfLw2YwPbe15zUJmtpuho9l2utP5hJRnLcQoOC+KYiGC/5gk0xsLTmwDWAwMaGv gR/PEOa9YjQT91yjxRc6p32Ox743/YVv5IrS0XyXsixMQ3h3PqO5Fs2af7bYriPqdrqhwletK3IqA +YvKHKjwHrjpRpNL6KnDvV81iZJyqcLtNI334ANwDRPKim221kDfax5c61owSHg8RA/jg4dEMaB1j WTd4sPDaC1YtXS63WmfLidsz384eJ0uz7pqMBcCzdgF98zoYw1sE/gEpe1oA+ACmhK8d9ptjCRqu5 qo7UIbpH/T0BDz93+yww==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1h5Cld-0006Is-Gn; Sat, 16 Mar 2019 17:06:41 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1h5ClZ-0006IR-I7 for linux-arm-kernel@lists.infradead.org; Sat, 16 Mar 2019 17:06:39 +0000 Received: from archlinux (cpc91196-cmbg18-2-0-cust659.5-4.cable.virginm.net [81.96.234.148]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 0409F2186A; Sat, 16 Mar 2019 17:06:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1552755996; bh=h3bu4jNOS0uOKLx0UOwrKkfVKdFvnUOM8ki1U4PdwRc=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=ORHJfEAEuW0ZGZekby7nf+KgyNVV+Y/VZ4Ln2VnmnHzZlqBRiPpjr9opSk9F8FNJm 8s6iyZCwWmG3ltcmCl9xl+zttXHJ+UkSDc3LMvLCiV0LE3xl4LBDVEKXyRP5q9cc/O ow2tM1gDyQeQHaP2rd9rPoACuF8pDhis3Z6fMFPk= Date: Sat, 16 Mar 2019 17:06:30 +0000 From: Jonathan Cameron To: Gregory CLEMENT Subject: Re: [PATCH 2/2] iio: adc: Add driver for the TI ADS8344 A/DC chips Message-ID: <20190316170630.18ab5970@archlinux> In-Reply-To: <20190315151152.30467-3-gregory.clement@bootlin.com> References: <20190315151152.30467-1-gregory.clement@bootlin.com> <20190315151152.30467-3-gregory.clement@bootlin.com> X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190316_100637_639548_7D68AF74 X-CRM114-Status: GOOD ( 24.64 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: devicetree@vger.kernel.org, Alexandre Belloni , Lars-Peter Clausen , Thomas Petazzoni , linux-iio@vger.kernel.org, Rob Herring , Peter Meerwald-Stadler , Hartmut Knaack , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, 15 Mar 2019 16:11:51 +0100 Gregory CLEMENT wrote: > This adds support for the Texas Instruments ADS8344 ADC chip. This chip > has a 16-bit 8-Channel ADC and is access directly through SPI. > > Signed-off-by: Gregory CLEMENT Hi Gregory, A few minor bits and pieces inline. Some of them due I would guess to cut and paste from a driver where things were slightly different! If we were late in the cycle this lot would probably have been small enough that I'd just have reworked it whilst applying, but we are really early, hence you get to tidy them up ;) Thanks, Jonathan > --- > drivers/iio/adc/Kconfig | 10 ++ > drivers/iio/adc/Makefile | 1 + > drivers/iio/adc/ti-ads8344.c | 216 +++++++++++++++++++++++++++++++++++ > 3 files changed, 227 insertions(+) > create mode 100644 drivers/iio/adc/ti-ads8344.c > > diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig > index 76db6e5cc296..447d3a871746 100644 > --- a/drivers/iio/adc/Kconfig > +++ b/drivers/iio/adc/Kconfig > @@ -967,6 +967,16 @@ config TI_ADS7950 > To compile this driver as a module, choose M here: the > module will be called ti-ads7950. > > +config TI_ADS8344 > + tristate "Texas Instruments ADS8344" > + depends on SPI && OF > + help > + If you say yes here you get support for Texas Instruments ADS8344 > + ADC chips > + > + This driver can also be built as a module. If so, the module will be > + called ti-ads8344. > + > config TI_ADS8688 > tristate "Texas Instruments ADS8688" > depends on SPI && OF > diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile > index 6fcebd167524..1f3ae934111d 100644 > --- a/drivers/iio/adc/Makefile > +++ b/drivers/iio/adc/Makefile > @@ -87,6 +87,7 @@ obj-$(CONFIG_TI_ADC128S052) += ti-adc128s052.o > obj-$(CONFIG_TI_ADC161S626) += ti-adc161s626.o > obj-$(CONFIG_TI_ADS1015) += ti-ads1015.o > obj-$(CONFIG_TI_ADS7950) += ti-ads7950.o > +obj-$(CONFIG_TI_ADS8344) += ti-ads8344.o > obj-$(CONFIG_TI_ADS8688) += ti-ads8688.o > obj-$(CONFIG_TI_ADS124S08) += ti-ads124s08.o > obj-$(CONFIG_TI_AM335X_ADC) += ti_am335x_adc.o > diff --git a/drivers/iio/adc/ti-ads8344.c b/drivers/iio/adc/ti-ads8344.c > new file mode 100644 > index 000000000000..6159d8518871 > --- /dev/null > +++ b/drivers/iio/adc/ti-ads8344.c > @@ -0,0 +1,216 @@ > +// SPDX-License-Identifier: GPL-2.0+ > +/* > + * ADS8344 16-bit 8-Channel ADC driver > + * > + * Author: Gregory CLEMENT > + * > + * Datasheet: http://www.ti.com/lit/ds/symlink/ads8344.pdf > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > + > +struct ads8344 { > + struct spi_device *spi; > + struct regulator *reg; > + struct mutex lock; > + > + u8 tx_buf ____cacheline_aligned; > + u16 rx_buf; > +}; > + > +#define ADS8344_VOLTAGE_CHANNEL(chan, si) \ > + { \ > + .type = IIO_VOLTAGE, \ > + .indexed = 1, \ > + .channel = chan, \ > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ > + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ > + .scan_index = si, \ > + .scan_type = { \ You aren't currently providing a buffer, so please drop scan_index and scan_type until you are. The code won't do anything with them at the moment. > + .sign = 'u', \ > + .realbits = 16, \ > + .storagebits = 16, \ > + }, \ > + } > + > +#define ADS8344_VOLTAGE_CHANNEL_DIFF(chan1, chan2, si) \ > + { \ > + .type = IIO_VOLTAGE, \ > + .indexed = 1, \ > + .channel = (chan1), \ > + .channel2 = (chan2), \ > + .differential = 1, \ > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ > + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ > + .scan_index = si, \ > + .scan_type = { \ > + .sign = 'u', \ > + .realbits = 16, \ > + .storagebits = 16, \ > + }, \ > + } > + > +static const struct iio_chan_spec ads8344_channels[] = { > + ADS8344_VOLTAGE_CHANNEL(0, 0), > + ADS8344_VOLTAGE_CHANNEL(1, 4), > + ADS8344_VOLTAGE_CHANNEL(2, 1), > + ADS8344_VOLTAGE_CHANNEL(3, 5), > + ADS8344_VOLTAGE_CHANNEL(4, 2), > + ADS8344_VOLTAGE_CHANNEL(5, 6), > + ADS8344_VOLTAGE_CHANNEL(6, 3), > + ADS8344_VOLTAGE_CHANNEL(7, 7), > + ADS8344_VOLTAGE_CHANNEL_DIFF(0, 1, 8), > + ADS8344_VOLTAGE_CHANNEL_DIFF(2, 3, 9), > + ADS8344_VOLTAGE_CHANNEL_DIFF(4, 5, 10), > + ADS8344_VOLTAGE_CHANNEL_DIFF(6, 7, 11), > + ADS8344_VOLTAGE_CHANNEL_DIFF(1, 0, 12), > + ADS8344_VOLTAGE_CHANNEL_DIFF(3, 2, 13), > + ADS8344_VOLTAGE_CHANNEL_DIFF(5, 4, 14), > + ADS8344_VOLTAGE_CHANNEL_DIFF(7, 6, 15), > +}; > + > +static int ads8344_adc_conversion(struct ads8344 *adc, int channel, > + bool differential) > +{ > + struct spi_device *spi = adc->spi; > + int ret; > + > + /* start bit */ > + adc->tx_buf = BIT(7); > + /* single-ended or differential */ > + adc->tx_buf |= differential ? 0 : BIT(2); > + /* select channel(s) */ The moment you need comments to say what a bit is, you are almost always better off adding some defines so that this block becomes something like. adc->tx_buff = ADS8344_START; if (!differential) adc->tx_buff |= ADS8344_SINGLE_END; adc->tx_buff |= ADS8344_CHANNEL(channel); adc->tx_buff |= ADS8344_CLOCK_INTERNAL; Then you can drop the comments and the defines are nice and easy to check against a datasheet as they are all in one place. > + adc->tx_buf |= channel << 4; > + /* internal clock mode */ > + adc->tx_buf |= 0x2; > + > + ret = spi_write(spi, &adc->tx_buf, 1); > + if (ret) > + return ret; > + > + udelay(9); > + > + ret = spi_read(spi, &adc->rx_buf, 2); > + if (ret) > + return ret; > + > + return adc->rx_buf; > +} > + > +static int ads8344_read_raw(struct iio_dev *iio, > + struct iio_chan_spec const *channel, int *value, > + int *shift, long mask) > +{ > + struct ads8344 *adc = iio_priv(iio); > + > + switch (mask) { > + case IIO_CHAN_INFO_RAW: > + mutex_lock(&adc->lock); > + *value = ads8344_adc_conversion(adc, channel->scan_index, > + channel->differential); > + mutex_unlock(&adc->lock); > + if (*value < 0) > + return *value; > + > + return IIO_VAL_INT; > + case IIO_CHAN_INFO_SCALE: > + *value = regulator_get_voltage(adc->reg); > + if (*value < 0) > + return *value; > + > + /* convert regulator output voltage to mV */ > + *value /= 1000; > + *shift = 16; > + > + return IIO_VAL_FRACTIONAL_LOG2; > + default: > + return -EINVAL; > + } > +} > + > +static const struct iio_info ads8344_info = { > + .read_raw = ads8344_read_raw, > +}; > + > +static int ads8344_probe(struct spi_device *spi) > +{ > + struct iio_dev *indio_dev; > + struct ads8344 *adc; > + int ret; > + > + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*adc)); > + if (!indio_dev) > + return -ENOMEM; > + > + adc = iio_priv(indio_dev); > + adc->spi = spi; > + mutex_init(&adc->lock); > + > + indio_dev->name = dev_name(&spi->dev); > + indio_dev->dev.parent = &spi->dev; > + indio_dev->dev.of_node = spi->dev.of_node; > + indio_dev->info = &ads8344_info; > + indio_dev->modes = INDIO_DIRECT_MODE; > + indio_dev->channels = ads8344_channels; > + indio_dev->num_channels = ARRAY_SIZE(ads8344_channels); > + > + adc->reg = devm_regulator_get(&spi->dev, "vref"); > + if (IS_ERR(adc->reg)) > + return PTR_ERR(adc->reg); > + > + ret = regulator_enable(adc->reg); > + if (ret) > + return ret; > + > + spi_set_drvdata(spi, indio_dev); > + > + ret = iio_device_register(indio_dev); > + if (ret) > + goto err_buffer_cleanup; > + > + return 0; > +err_buffer_cleanup: That is not a useful or correct label.. Give it a better name! > + regulator_disable(adc->reg); > + > + return ret; > +} > + > +static int ads8344_remove(struct spi_device *spi) > +{ > + struct iio_dev *indio_dev = spi_get_drvdata(spi); > + struct ads8344 *adc = iio_priv(indio_dev); > + > + iio_device_unregister(indio_dev); > + regulator_disable(adc->reg); > + > + return 0; > +} > + > +#ifdef CONFIG_OF Given there isn't currently any other way of (normally at least) instantiating this I wouldn't bother with the config guards. Also see below for additional comment on this. > + > +static const struct of_device_id ads8344_dt_ids[] = { > + { .compatible = "ti,ads8344", }, > + {} > +}; > +MODULE_DEVICE_TABLE(of, ads8344_dt_ids); > + > +#endif > + > +static struct spi_driver ads8344_driver = { > + .driver = { > + .name = "ads8344", > + .of_match_table = of_match_ptr(ads8344_dt_ids), Don't use of_match_ptr as it breaks the magic ACPI binding which uses the DT tables. > + }, > + .probe = ads8344_probe, > + .remove = ads8344_remove, > +}; > +module_spi_driver(ads8344_driver); > + > +MODULE_AUTHOR("Gregory CLEMENT "); > +MODULE_DESCRIPTION("ADS8344 driver"); > +MODULE_LICENSE("GPL v2"); _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel