From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756884AbaIQWU2 (ORCPT ); Wed, 17 Sep 2014 18:20:28 -0400 Received: from mout.gmx.net ([212.227.15.15]:58658 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755815AbaIQWU0 (ORCPT ); Wed, 17 Sep 2014 18:20:26 -0400 Message-ID: <541A0910.90806@gmx.de> Date: Thu, 18 Sep 2014 00:20:00 +0200 From: Hartmut Knaack User-Agent: Mozilla/5.0 (X11; Linux i686; rv:29.0) Gecko/20100101 Firefox/29.0 SeaMonkey/2.26.1 MIME-Version: 1.0 To: Jacob Pan , IIO , LKML , DEVICE TREE , Lee Jones CC: Carlo Caione , Srinivas Pandruvada , Aaron Lu , Alan Cox , Samuel Ortiz , Liam Girdwood , Mark Brown , Grant Likely , Greg Kroah-Hartman , Rob Herring , Lars-Peter Clausen , Fugang Duan , Arnd Bergmann , Zubair Lutfullah , Sebastian Reichel , Johannes Thumshirn , Philippe Reynes , Angelo Compagnucci , Doug Anderson , Ramakrishna Pallala , Peter Meerwald , Maxime Ripard , Rafael Wysocki Subject: Re: [PATCH v4 2/3] iio/adc: add support for axp288 adc References: <1410912715-25903-1-git-send-email-jacob.jun.pan@linux.intel.com> <1410912715-25903-3-git-send-email-jacob.jun.pan@linux.intel.com> In-Reply-To: <1410912715-25903-3-git-send-email-jacob.jun.pan@linux.intel.com> Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit X-Provags-ID: V03:K0:z07Nl0rMoYokhlmC2JxVd4FGtBOqXL3jHWLatTzDShtz2pB+THb P8t5T+Zdqc9Fzqx8Ep334boo17fmc9tpzwk4F9vj6fymii6Wm6SE4rJWEYC3/UdPawCIPJL ehEdlEO4DsxxoTcfnAg2fnlh4EzY8oxKhnd4kWRnO1DjW3JSeLbzK/ZA9MlJw5yvds9rf8w 16u649otk1nzfiAt6aEUQ== X-UI-Out-Filterresults: notjunk:1; Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Jacob Pan schrieb, Am 17.09.2014 02:11: > Platform driver for X-Powers AXP288 ADC, which is a sub-device of the > customized AXP288 PMIC for Intel Baytrail-CR platforms. GPADC device > enumerates as one of the MFD cell devices. It uses IIO infrastructure > to communicate with userspace and consumer drivers. > > Usages of ADC channels include battery charging and thermal sensors. > You are progressing, but still a few issues left. One thing is indentation in some places (I feel like being pretty annoying about this), others are commented in line. > Based on initial work by: > Ramakrishna Pallala > > Signed-off-by: Jacob Pan > --- > drivers/iio/adc/Kconfig | 8 ++ > drivers/iio/adc/Makefile | 1 + > drivers/iio/adc/axp288_adc.c | 254 +++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 263 insertions(+) > create mode 100644 drivers/iio/adc/axp288_adc.c > > diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig > index 11b048a..db2681b 100644 > --- a/drivers/iio/adc/Kconfig > +++ b/drivers/iio/adc/Kconfig > @@ -127,6 +127,14 @@ config AT91_ADC > help > Say yes here to build support for Atmel AT91 ADC. > > +config AXP288_ADC > + tristate "X-Powers AXP288 ADC driver" > + depends on MFD_AXP20X > + help > + Say yes here to have support for X-Powers power management IC (PMIC) ADC > + device. Depending on platform configuration, this general purpose ADC can > + be used for sampling sensors such as thermal resistors. > + > config EXYNOS_ADC > tristate "Exynos ADC driver support" > depends on ARCH_EXYNOS || (OF && COMPILE_TEST) > diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile > index ad81b51..19640f9 100644 > --- a/drivers/iio/adc/Makefile > +++ b/drivers/iio/adc/Makefile > @@ -14,6 +14,7 @@ obj-$(CONFIG_AD7793) += ad7793.o > obj-$(CONFIG_AD7887) += ad7887.o > obj-$(CONFIG_AD799X) += ad799x.o > obj-$(CONFIG_AT91_ADC) += at91_adc.o > +obj-$(CONFIG_AXP288_ADC) += axp288_adc.o > obj-$(CONFIG_EXYNOS_ADC) += exynos_adc.o > obj-$(CONFIG_LP8788_ADC) += lp8788_adc.o > obj-$(CONFIG_MAX1027) += max1027.o > diff --git a/drivers/iio/adc/axp288_adc.c b/drivers/iio/adc/axp288_adc.c > new file mode 100644 > index 0000000..333c624 > --- /dev/null > +++ b/drivers/iio/adc/axp288_adc.c > @@ -0,0 +1,254 @@ > +/* > + * axp288_adc.c - X-Powers AXP288 PMIC ADC Driver > + * > + * Copyright (C) 2014 Intel Corporation > + * > + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License as published by > + * the Free Software Foundation; version 2 of the License. > + * > + * This program is distributed in the hope that it will be useful, but > + * WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU > + * General Public License for more details. > + * > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > + > +#include > +#include > +#include > + > +#define AXP288_ADC_EN_MASK 0xF1 > +#define AXP288_ADC_TS_PIN_GPADC 0xF2 > +#define AXP288_ADC_TS_PIN_ON 0xF3 > + > +enum axp288_adc_id { > + AXP288_ADC_TS, > + AXP288_ADC_PMIC, > + AXP288_ADC_GP, > + AXP288_ADC_BATT_CHRG_I, > + AXP288_ADC_BATT_DISCHRG_I, > + AXP288_ADC_BATT_V, > + AXP288_ADC_NR_CHAN, > +}; > + > +struct axp288_adc_info { > + int irq; > + struct device *dev; > + struct regmap *regmap; > +}; > + > +static const struct iio_chan_spec const axp288_adc_channels[] = { > + { > + .indexed = 1, > + .type = IIO_TEMP, > + .channel = 0, > + .address = AXP288_TS_ADC_H, > + .datasheet_name = "CH0", > + }, { > + .indexed = 1, > + .type = IIO_TEMP, > + .channel = 1, > + .address = AXP288_PMIC_ADC_H, > + .datasheet_name = "CH1", > + }, { > + .indexed = 1, > + .type = IIO_TEMP, > + .channel = 2, > + .address = AXP288_GP_ADC_H, > + .datasheet_name = "CH2", > + }, { > + .indexed = 1, > + .type = IIO_CURRENT, > + .channel = 3, > + .address = AXP20X_BATT_CHRG_I_H, > + .datasheet_name = "CH3", > + .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), > + }, { > + .indexed = 1, > + .type = IIO_CURRENT, > + .channel = 4, > + .address = AXP20X_BATT_DISCHRG_I_H, > + .datasheet_name = "CH4", > + .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), > + }, { > + .indexed = 1, > + .type = IIO_VOLTAGE, > + .channel = 5, > + .address = AXP20X_BATT_V_H, > + .datasheet_name = "CH5", > + .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), > + }, > +}; > + > +#define AXP288_ADC_MAP(_adc_channel_label, _consumer_dev_name, \ > + _consumer_channel) \ > + { \ > + .adc_channel_label = _adc_channel_label, \ > + .consumer_dev_name = _consumer_dev_name, \ > + .consumer_channel = _consumer_channel, \ > + } > + > +/* for consumer drivers */ > +static struct iio_map axp288_adc_default_maps[] = { > + AXP288_ADC_MAP("TS_PIN", "axp288-batt", "axp288-batt-temp"), > + AXP288_ADC_MAP("PMIC_TEMP", "axp288-pmic", "axp288-pmic-temp"), > + AXP288_ADC_MAP("GPADC", "axp288-gpadc", "axp288-system-temp"), > + AXP288_ADC_MAP("BATT_CHG_I", "axp288-chrg", "axp288-chrg-curr"), > + AXP288_ADC_MAP("BATT_DISCHRG_I", "axp288-chrg", "axp288-chrg-d-curr"), > + AXP288_ADC_MAP("BATT_V", "axp288-batt", "axp288-batt-volt"), > + {}, > +}; > + > +static int axp288_adc_read_raw(struct iio_dev *indio_dev, > + struct iio_chan_spec const *chan, > + int *val, int *val2, long mask) > +{ > + int ret; > + struct axp288_adc_info *info = iio_priv(indio_dev); > + u8 buf[2]; You could use __be16 instead. Then you just need to use be16_to_cpu(), shift 4 bits to the right and mask the result with 0xFF. > + > + mutex_lock(&indio_dev->mlock); > + switch (mask) { > + case IIO_CHAN_INFO_RAW: > + /* special case for GPADC sample */ > + if (chan->address == AXP288_GP_ADC_H) { > + ret = regmap_write(info->regmap, AXP288_ADC_TS_PIN_CTRL, > + AXP288_ADC_TS_PIN_GPADC); > + if (ret) { > + dev_err(&indio_dev->dev, "GPADC mode\n"); > + mutex_unlock(&indio_dev->mlock); > + return ret; You may even just goto the mutex_unlock at the end of the function. Would safe a few bytes here in the source - up to you. More interesting is, if the error message is required, as you don't have one below, when switching to TS_PIN_ON. > + } > + } > + case IIO_CHAN_INFO_PROCESSED: > + ret = regmap_bulk_read(info->regmap, chan->address, buf, 2); > + if (ret) { > + dev_err(&indio_dev->dev, "sample raw data failed\n"); > + break; > + } > + *val = (buf[0] << 4) + ((buf[1] >> 4) & 0x0F); > + ret = IIO_VAL_INT; > + break; > + default: > + ret = -EINVAL; > + } > + > + if (mask == IIO_CHAN_INFO_RAW && chan->address == AXP288_GP_ADC_H) > + ret = regmap_write(info->regmap, AXP288_ADC_TS_PIN_CTRL, > + AXP288_ADC_TS_PIN_ON); > + > + mutex_unlock(&indio_dev->mlock); > + > + return ret; > +} > + > +static int axp288_adc_enable(struct regmap *regmap, bool enable) > +{ > + unsigned int pin_on, adc_en; > + > + if (enable) { > + pin_on = AXP288_ADC_TS_PIN_ON; > + adc_en = AXP288_ADC_EN_MASK; > + } else { > + pin_on = ~AXP288_ADC_TS_PIN_ON; > + adc_en = ~AXP288_ADC_EN_MASK; > + } > + if (regmap_write(regmap, AXP288_ADC_TS_PIN_CTRL, pin_on)) > + return -EIO; > + > + return regmap_write(regmap, AXP20X_ADC_EN1, ~AXP288_ADC_EN_MASK); So, what's the deal about the variable adc_en? > +} > + > +static const struct iio_info axp288_adc_iio_info = { > + .read_raw = &axp288_adc_read_raw, > + .driver_module = THIS_MODULE, > +}; > + > +static int axp288_adc_probe(struct platform_device *pdev) > +{ > + int ret; > + struct axp288_adc_info *info; > + struct iio_dev *indio_dev; > + struct axp20x_dev *axp20x = dev_get_drvdata(pdev->dev.parent); > + > + indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*info)); > + if (!indio_dev) > + return -ENOMEM; > + > + info = iio_priv(indio_dev); > + info->irq = platform_get_irq(pdev, 0); > + if (info->irq < 0) { > + dev_err(&pdev->dev, "no irq resource?\n"); > + return info->irq; > + } > + platform_set_drvdata(pdev, indio_dev); > + info->regmap = axp20x->regmap; > + ret = axp288_adc_enable(axp20x->regmap, true); > + if (ret) { > + dev_err(&pdev->dev, "Unable to enable ADC device\n"); > + return ret; > + } > + > + indio_dev->dev.parent = &pdev->dev; > + indio_dev->name = pdev->name; > + indio_dev->channels = axp288_adc_channels; > + indio_dev->num_channels = ARRAY_SIZE(axp288_adc_channels); > + indio_dev->info = &axp288_adc_iio_info; > + indio_dev->modes = INDIO_DIRECT_MODE; > + ret = iio_map_array_register(indio_dev, axp288_adc_default_maps); > + if (ret < 0) > + goto err_disable_dev; > + > + ret = iio_device_register(indio_dev); > + if (ret < 0) { > + dev_err(&pdev->dev, "unable to register iio device\n"); > + goto err_array_unregister; > + } > + > + return 0; > + > +err_array_unregister: > + iio_map_array_unregister(indio_dev); > +err_disable_dev: > + ret = axp288_adc_enable(axp20x->regmap, false); Don't set ret here. We want to return the error code from the function that failed above. > + > + return ret; > +} > + > +static int axp288_adc_remove(struct platform_device *pdev) > +{ > + struct iio_dev *indio_dev = platform_get_drvdata(pdev); > + struct axp20x_dev *axp20x = dev_get_drvdata(pdev->dev.parent); > + > + if (axp288_adc_enable(axp20x->regmap, false)) > + dev_err(&pdev->dev, "Unable to disable ADC device\n"); > + iio_device_unregister(indio_dev); > + iio_map_array_unregister(indio_dev); > + > + return 0; > +} > + > +static struct platform_driver axp288_adc_driver = { > + .probe = axp288_adc_probe, > + .remove = axp288_adc_remove, > + .driver = { > + .name = "axp288_adc", > + .owner = THIS_MODULE, > + }, > +}; > + > +module_platform_driver(axp288_adc_driver); > + > +MODULE_AUTHOR("Jacob Pan "); > +MODULE_DESCRIPTION("X-Powers AXP288 ADC Driver"); > +MODULE_LICENSE("GPL"); > From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hartmut Knaack Subject: Re: [PATCH v4 2/3] iio/adc: add support for axp288 adc Date: Thu, 18 Sep 2014 00:20:00 +0200 Message-ID: <541A0910.90806@gmx.de> References: <1410912715-25903-1-git-send-email-jacob.jun.pan@linux.intel.com> <1410912715-25903-3-git-send-email-jacob.jun.pan@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1410912715-25903-3-git-send-email-jacob.jun.pan-VuQAYsv1563Yd54FQh9/CA@public.gmane.org> Sender: linux-iio-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Jacob Pan , IIO , LKML , DEVICE TREE , Lee Jones Cc: Carlo Caione , Srinivas Pandruvada , Aaron Lu , Alan Cox , Samuel Ortiz , Liam Girdwood , Mark Brown , Grant Likely , Greg Kroah-Hartman , Rob Herring , Lars-Peter Clausen , Fugang Duan , Arnd Bergmann , Zubair Lutfullah , Sebastian Reichel , Johannes Thumshirn , Philippe Reynes , Angelo Compagnucci , Doug Anderson , Ramakrishna Pallala , Peter Meerwald , Maxime Ripard List-Id: devicetree@vger.kernel.org Jacob Pan schrieb, Am 17.09.2014 02:11: > Platform driver for X-Powers AXP288 ADC, which is a sub-device of the > customized AXP288 PMIC for Intel Baytrail-CR platforms. GPADC device > enumerates as one of the MFD cell devices. It uses IIO infrastructure > to communicate with userspace and consumer drivers. > > Usages of ADC channels include battery charging and thermal sensors. > You are progressing, but still a few issues left. One thing is indentation in some places (I feel like being pretty annoying about this), others are commented in line. > Based on initial work by: > Ramakrishna Pallala > > Signed-off-by: Jacob Pan > --- > drivers/iio/adc/Kconfig | 8 ++ > drivers/iio/adc/Makefile | 1 + > drivers/iio/adc/axp288_adc.c | 254 +++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 263 insertions(+) > create mode 100644 drivers/iio/adc/axp288_adc.c > > diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig > index 11b048a..db2681b 100644 > --- a/drivers/iio/adc/Kconfig > +++ b/drivers/iio/adc/Kconfig > @@ -127,6 +127,14 @@ config AT91_ADC > help > Say yes here to build support for Atmel AT91 ADC. > > +config AXP288_ADC > + tristate "X-Powers AXP288 ADC driver" > + depends on MFD_AXP20X > + help > + Say yes here to have support for X-Powers power management IC (PMIC) ADC > + device. Depending on platform configuration, this general purpose ADC can > + be used for sampling sensors such as thermal resistors. > + > config EXYNOS_ADC > tristate "Exynos ADC driver support" > depends on ARCH_EXYNOS || (OF && COMPILE_TEST) > diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile > index ad81b51..19640f9 100644 > --- a/drivers/iio/adc/Makefile > +++ b/drivers/iio/adc/Makefile > @@ -14,6 +14,7 @@ obj-$(CONFIG_AD7793) += ad7793.o > obj-$(CONFIG_AD7887) += ad7887.o > obj-$(CONFIG_AD799X) += ad799x.o > obj-$(CONFIG_AT91_ADC) += at91_adc.o > +obj-$(CONFIG_AXP288_ADC) += axp288_adc.o > obj-$(CONFIG_EXYNOS_ADC) += exynos_adc.o > obj-$(CONFIG_LP8788_ADC) += lp8788_adc.o > obj-$(CONFIG_MAX1027) += max1027.o > diff --git a/drivers/iio/adc/axp288_adc.c b/drivers/iio/adc/axp288_adc.c > new file mode 100644 > index 0000000..333c624 > --- /dev/null > +++ b/drivers/iio/adc/axp288_adc.c > @@ -0,0 +1,254 @@ > +/* > + * axp288_adc.c - X-Powers AXP288 PMIC ADC Driver > + * > + * Copyright (C) 2014 Intel Corporation > + * > + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License as published by > + * the Free Software Foundation; version 2 of the License. > + * > + * This program is distributed in the hope that it will be useful, but > + * WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU > + * General Public License for more details. > + * > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > + > +#include > +#include > +#include > + > +#define AXP288_ADC_EN_MASK 0xF1 > +#define AXP288_ADC_TS_PIN_GPADC 0xF2 > +#define AXP288_ADC_TS_PIN_ON 0xF3 > + > +enum axp288_adc_id { > + AXP288_ADC_TS, > + AXP288_ADC_PMIC, > + AXP288_ADC_GP, > + AXP288_ADC_BATT_CHRG_I, > + AXP288_ADC_BATT_DISCHRG_I, > + AXP288_ADC_BATT_V, > + AXP288_ADC_NR_CHAN, > +}; > + > +struct axp288_adc_info { > + int irq; > + struct device *dev; > + struct regmap *regmap; > +}; > + > +static const struct iio_chan_spec const axp288_adc_channels[] = { > + { > + .indexed = 1, > + .type = IIO_TEMP, > + .channel = 0, > + .address = AXP288_TS_ADC_H, > + .datasheet_name = "CH0", > + }, { > + .indexed = 1, > + .type = IIO_TEMP, > + .channel = 1, > + .address = AXP288_PMIC_ADC_H, > + .datasheet_name = "CH1", > + }, { > + .indexed = 1, > + .type = IIO_TEMP, > + .channel = 2, > + .address = AXP288_GP_ADC_H, > + .datasheet_name = "CH2", > + }, { > + .indexed = 1, > + .type = IIO_CURRENT, > + .channel = 3, > + .address = AXP20X_BATT_CHRG_I_H, > + .datasheet_name = "CH3", > + .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), > + }, { > + .indexed = 1, > + .type = IIO_CURRENT, > + .channel = 4, > + .address = AXP20X_BATT_DISCHRG_I_H, > + .datasheet_name = "CH4", > + .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), > + }, { > + .indexed = 1, > + .type = IIO_VOLTAGE, > + .channel = 5, > + .address = AXP20X_BATT_V_H, > + .datasheet_name = "CH5", > + .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), > + }, > +}; > + > +#define AXP288_ADC_MAP(_adc_channel_label, _consumer_dev_name, \ > + _consumer_channel) \ > + { \ > + .adc_channel_label = _adc_channel_label, \ > + .consumer_dev_name = _consumer_dev_name, \ > + .consumer_channel = _consumer_channel, \ > + } > + > +/* for consumer drivers */ > +static struct iio_map axp288_adc_default_maps[] = { > + AXP288_ADC_MAP("TS_PIN", "axp288-batt", "axp288-batt-temp"), > + AXP288_ADC_MAP("PMIC_TEMP", "axp288-pmic", "axp288-pmic-temp"), > + AXP288_ADC_MAP("GPADC", "axp288-gpadc", "axp288-system-temp"), > + AXP288_ADC_MAP("BATT_CHG_I", "axp288-chrg", "axp288-chrg-curr"), > + AXP288_ADC_MAP("BATT_DISCHRG_I", "axp288-chrg", "axp288-chrg-d-curr"), > + AXP288_ADC_MAP("BATT_V", "axp288-batt", "axp288-batt-volt"), > + {}, > +}; > + > +static int axp288_adc_read_raw(struct iio_dev *indio_dev, > + struct iio_chan_spec const *chan, > + int *val, int *val2, long mask) > +{ > + int ret; > + struct axp288_adc_info *info = iio_priv(indio_dev); > + u8 buf[2]; You could use __be16 instead. Then you just need to use be16_to_cpu(), shift 4 bits to the right and mask the result with 0xFF. > + > + mutex_lock(&indio_dev->mlock); > + switch (mask) { > + case IIO_CHAN_INFO_RAW: > + /* special case for GPADC sample */ > + if (chan->address == AXP288_GP_ADC_H) { > + ret = regmap_write(info->regmap, AXP288_ADC_TS_PIN_CTRL, > + AXP288_ADC_TS_PIN_GPADC); > + if (ret) { > + dev_err(&indio_dev->dev, "GPADC mode\n"); > + mutex_unlock(&indio_dev->mlock); > + return ret; You may even just goto the mutex_unlock at the end of the function. Would safe a few bytes here in the source - up to you. More interesting is, if the error message is required, as you don't have one below, when switching to TS_PIN_ON. > + } > + } > + case IIO_CHAN_INFO_PROCESSED: > + ret = regmap_bulk_read(info->regmap, chan->address, buf, 2); > + if (ret) { > + dev_err(&indio_dev->dev, "sample raw data failed\n"); > + break; > + } > + *val = (buf[0] << 4) + ((buf[1] >> 4) & 0x0F); > + ret = IIO_VAL_INT; > + break; > + default: > + ret = -EINVAL; > + } > + > + if (mask == IIO_CHAN_INFO_RAW && chan->address == AXP288_GP_ADC_H) > + ret = regmap_write(info->regmap, AXP288_ADC_TS_PIN_CTRL, > + AXP288_ADC_TS_PIN_ON); > + > + mutex_unlock(&indio_dev->mlock); > + > + return ret; > +} > + > +static int axp288_adc_enable(struct regmap *regmap, bool enable) > +{ > + unsigned int pin_on, adc_en; > + > + if (enable) { > + pin_on = AXP288_ADC_TS_PIN_ON; > + adc_en = AXP288_ADC_EN_MASK; > + } else { > + pin_on = ~AXP288_ADC_TS_PIN_ON; > + adc_en = ~AXP288_ADC_EN_MASK; > + } > + if (regmap_write(regmap, AXP288_ADC_TS_PIN_CTRL, pin_on)) > + return -EIO; > + > + return regmap_write(regmap, AXP20X_ADC_EN1, ~AXP288_ADC_EN_MASK); So, what's the deal about the variable adc_en? > +} > + > +static const struct iio_info axp288_adc_iio_info = { > + .read_raw = &axp288_adc_read_raw, > + .driver_module = THIS_MODULE, > +}; > + > +static int axp288_adc_probe(struct platform_device *pdev) > +{ > + int ret; > + struct axp288_adc_info *info; > + struct iio_dev *indio_dev; > + struct axp20x_dev *axp20x = dev_get_drvdata(pdev->dev.parent); > + > + indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*info)); > + if (!indio_dev) > + return -ENOMEM; > + > + info = iio_priv(indio_dev); > + info->irq = platform_get_irq(pdev, 0); > + if (info->irq < 0) { > + dev_err(&pdev->dev, "no irq resource?\n"); > + return info->irq; > + } > + platform_set_drvdata(pdev, indio_dev); > + info->regmap = axp20x->regmap; > + ret = axp288_adc_enable(axp20x->regmap, true); > + if (ret) { > + dev_err(&pdev->dev, "Unable to enable ADC device\n"); > + return ret; > + } > + > + indio_dev->dev.parent = &pdev->dev; > + indio_dev->name = pdev->name; > + indio_dev->channels = axp288_adc_channels; > + indio_dev->num_channels = ARRAY_SIZE(axp288_adc_channels); > + indio_dev->info = &axp288_adc_iio_info; > + indio_dev->modes = INDIO_DIRECT_MODE; > + ret = iio_map_array_register(indio_dev, axp288_adc_default_maps); > + if (ret < 0) > + goto err_disable_dev; > + > + ret = iio_device_register(indio_dev); > + if (ret < 0) { > + dev_err(&pdev->dev, "unable to register iio device\n"); > + goto err_array_unregister; > + } > + > + return 0; > + > +err_array_unregister: > + iio_map_array_unregister(indio_dev); > +err_disable_dev: > + ret = axp288_adc_enable(axp20x->regmap, false); Don't set ret here. We want to return the error code from the function that failed above. > + > + return ret; > +} > + > +static int axp288_adc_remove(struct platform_device *pdev) > +{ > + struct iio_dev *indio_dev = platform_get_drvdata(pdev); > + struct axp20x_dev *axp20x = dev_get_drvdata(pdev->dev.parent); > + > + if (axp288_adc_enable(axp20x->regmap, false)) > + dev_err(&pdev->dev, "Unable to disable ADC device\n"); > + iio_device_unregister(indio_dev); > + iio_map_array_unregister(indio_dev); > + > + return 0; > +} > + > +static struct platform_driver axp288_adc_driver = { > + .probe = axp288_adc_probe, > + .remove = axp288_adc_remove, > + .driver = { > + .name = "axp288_adc", > + .owner = THIS_MODULE, > + }, > +}; > + > +module_platform_driver(axp288_adc_driver); > + > +MODULE_AUTHOR("Jacob Pan "); > +MODULE_DESCRIPTION("X-Powers AXP288 ADC Driver"); > +MODULE_LICENSE("GPL"); >