From patchwork Thu Jun 20 18:57:53 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexandre Belloni X-Patchwork-Id: 2757811 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 27C259F472 for ; Thu, 20 Jun 2013 19:00:54 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 623D8202ED for ; Thu, 20 Jun 2013 19:00:52 +0000 (UTC) Received: from casper.infradead.org (casper.infradead.org [85.118.1.10]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 8E258202EC for ; Thu, 20 Jun 2013 19:00:48 +0000 (UTC) Received: from merlin.infradead.org ([2001:4978:20e::2]) by casper.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1Upk4r-0003Lf-Ig; Thu, 20 Jun 2013 18:59:26 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1Upk4X-00072E-TL; Thu, 20 Jun 2013 18:59:06 +0000 Received: from mail.free-electrons.com ([94.23.35.102]) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1Upk3y-0006yH-75 for linux-arm-kernel@lists.infradead.org; Thu, 20 Jun 2013 18:58:34 +0000 Received: by mail.free-electrons.com (Postfix, from userid 106) id 9149D7CD; Thu, 20 Jun 2013 20:58:09 +0200 (CEST) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Spam-Level: X-Spam-Status: No, score=-5.5 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 Received: from localhost (128-79-216-144.hfc.dyn.abo.bbox.fr [128.79.216.144]) by mail.free-electrons.com (Postfix) with ESMTPSA id CCBA7786; Thu, 20 Jun 2013 20:58:08 +0200 (CEST) From: Alexandre Belloni To: Shawn Guo , Grant Likely Subject: [PATCHv2 1/3] iio: Add Nuvoton NAU7802 ADC driver Date: Thu, 20 Jun 2013 20:57:53 +0200 Message-Id: <1371754675-12242-2-git-send-email-alexandre.belloni@free-electrons.com> X-Mailer: git-send-email 1.8.1.2 In-Reply-To: <1371754675-12242-1-git-send-email-alexandre.belloni@free-electrons.com> References: <1371754675-12242-1-git-send-email-alexandre.belloni@free-electrons.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20130620_145830_622501_082AAB32 X-CRM114-Status: GOOD ( 23.47 ) X-Spam-Score: -3.2 (---) Cc: brian@crystalfontz.com, linux-doc@vger.kernel.org, linux-iio@vger.kernel.org, devicetree-discuss@lists.ozlabs.org, jimwall@q.com, Rob Herring , linux-kernel@vger.kernel.org, Alexandre Belloni , Jonathan Cameron , Rob Landley , Maxime Ripard , linux-arm-kernel@lists.infradead.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP The Nuvoton NAU7802 ADC is a 24-bit 2-channels I2C ADC, with adjustable gain and sampling rates. Signed-off-by: Alexandre Belloni Signed-off-by: Maxime Ripard --- .../bindings/iio/adc/nuvoton-nau7802.txt | 17 + drivers/iio/adc/Kconfig | 9 + drivers/iio/adc/Makefile | 1 + drivers/iio/adc/nau7802.c | 603 +++++++++++++++++++++ 4 files changed, 630 insertions(+) create mode 100644 Documentation/devicetree/bindings/iio/adc/nuvoton-nau7802.txt create mode 100644 drivers/iio/adc/nau7802.c diff --git a/Documentation/devicetree/bindings/iio/adc/nuvoton-nau7802.txt b/Documentation/devicetree/bindings/iio/adc/nuvoton-nau7802.txt new file mode 100644 index 0000000..9bc4218 --- /dev/null +++ b/Documentation/devicetree/bindings/iio/adc/nuvoton-nau7802.txt @@ -0,0 +1,17 @@ +* Nuvoton NAU7802 Analog to Digital Converter (ADC) + +Required properties: + - compatible: Should be "nuvoton,nau7802" + - reg: Should contain the ADC I2C address + +Optional properties: + - nuvoton,vldo: Reference voltage in millivolts (integer) + - interrupts: IRQ line for the ADC. If not used the driver will use + polling. + +Example: +adc2: nau7802@2a { + compatible = "nuvoton,nau7802"; + reg = <0x2a>; + nuvoton,vldo = <3000>; +}; diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig index ab0767e6..d7f9ed8 100644 --- a/drivers/iio/adc/Kconfig +++ b/drivers/iio/adc/Kconfig @@ -133,6 +133,15 @@ config MAX1363 max11646, max11647) Provides direct access via sysfs and buffered data via the iio dev interface. +config NAU7802 + tristate "Nuvoton NAU7802 ADC driver" + depends on I2C + help + Say yes here to build support for Nuvoton NAU7802 ADC. + + To compile this driver as a module, choose M here: the + module will be called nau7802. + config TI_ADC081C tristate "Texas Instruments ADC081C021/027" depends on I2C diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile index 0a825be..d426081 100644 --- a/drivers/iio/adc/Makefile +++ b/drivers/iio/adc/Makefile @@ -14,6 +14,7 @@ obj-$(CONFIG_AT91_ADC) += at91_adc.o obj-$(CONFIG_EXYNOS_ADC) += exynos_adc.o obj-$(CONFIG_LP8788_ADC) += lp8788_adc.o obj-$(CONFIG_MAX1363) += max1363.o +obj-$(CONFIG_NAU7802) += nau7802.o obj-$(CONFIG_TI_ADC081C) += ti-adc081c.o obj-$(CONFIG_TI_AM335X_ADC) += ti_am335x_adc.o obj-$(CONFIG_VIPERBOARD_ADC) += viperboard_adc.o diff --git a/drivers/iio/adc/nau7802.c b/drivers/iio/adc/nau7802.c new file mode 100644 index 0000000..e1b6981 --- /dev/null +++ b/drivers/iio/adc/nau7802.c @@ -0,0 +1,603 @@ +/* + * Driver for the Nuvoton NAU7802 ADC + * + * Copyright 2013 Free Electrons + * + * Licensed under the GPLv2 or later. + */ + +#include +#include +#include +#include +#include +#include + +#include +#include + +#define NAU7802_REG_PUCTRL 0x00 +#define NAU7802_PUCTRL_RR(x) (x << 0) +#define NAU7802_PUCTRL_RR_BIT NAU7802_PUCTRL_RR(1) +#define NAU7802_PUCTRL_PUD(x) (x << 1) +#define NAU7802_PUCTRL_PUD_BIT NAU7802_PUCTRL_PUD(1) +#define NAU7802_PUCTRL_PUA(x) (x << 2) +#define NAU7802_PUCTRL_PUA_BIT NAU7802_PUCTRL_PUA(1) +#define NAU7802_PUCTRL_PUR(x) (x << 3) +#define NAU7802_PUCTRL_PUR_BIT NAU7802_PUCTRL_PUR(1) +#define NAU7802_PUCTRL_CS(x) (x << 4) +#define NAU7802_PUCTRL_CS_BIT NAU7802_PUCTRL_CS(1) +#define NAU7802_PUCTRL_CR(x) (x << 5) +#define NAU7802_PUCTRL_CR_BIT NAU7802_PUCTRL_CR(1) +#define NAU7802_PUCTRL_AVDDS(x) (x << 7) +#define NAU7802_PUCTRL_AVDDS_BIT NAU7802_PUCTRL_AVDDS(1) +#define NAU7802_REG_CTRL1 0x01 +#define NAU7802_CTRL1_VLDO(x) (x << 3) +#define NAU7802_CTRL1_GAINS(x) (x) +#define NAU7802_CTRL1_GAINS_BITS 0x07 +#define NAU7802_REG_CTRL2 0x02 +#define NAU7802_CTRL2_CHS(x) (x << 7) +#define NAU7802_CTRL2_CRS(x) (x << 4) +#define NAU7802_SAMP_FREQ_320 0x07 +#define NAU7802_CTRL2_CHS_BIT NAU7802_CTRL2_CHS(1) +#define NAU7802_REG_ADC_B2 0x12 +#define NAU7802_REG_ADC_B1 0x13 +#define NAU7802_REG_ADC_B0 0x14 +#define NAU7802_REG_ADC_CTRL 0x15 + +#define NAU7802_DEFAULT_CONVERSIONS 6 + +struct nau7802_state { + struct i2c_client *client; + s32 last_value; + struct mutex lock; + struct mutex data_lock; + u32 vref_mv; + u32 conversion_count; + u32 min_conversions; + u8 sample_rate; + u32 scale_avail[8]; + struct completion value_ok; +}; + +#define NAU7802_CHANNEL(chan) { \ + .type = IIO_VOLTAGE, \ + .indexed = 1, \ + .channel = (chan), \ + .scan_index = (chan), \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \ + BIT(IIO_CHAN_INFO_SAMP_FREQ) \ +} + +static const struct iio_chan_spec nau7802_chan_array[] = { + NAU7802_CHANNEL(0), + NAU7802_CHANNEL(1), +}; + +static const u16 nau7802_sample_freq_avail[] = {10, 20, 40, 80, + 10, 10, 10, 320}; + +static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("10 40 80 320"); + +static ssize_t nau7802_sysfs_set_min_conversions(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t len) +{ + struct iio_dev *indio_dev = dev_to_iio_dev(dev); + struct nau7802_state *st = iio_priv(indio_dev); + u32 val; + int ret; + + ret = kstrtouint(buf, 10, &val); + if (ret) + return ret; + + mutex_lock(&st->lock); + st->min_conversions = val; + st->conversion_count = 0; + mutex_unlock(&st->lock); + + return len; +} + +static ssize_t nau7802_sysfs_get_min_conversions(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *indio_dev = dev_to_iio_dev(dev); + struct nau7802_state *st = iio_priv(indio_dev); + + return sprintf(buf, "%d\n", st->min_conversions); +} + +static IIO_DEVICE_ATTR(min_conversions, S_IWUSR | S_IRUGO, + nau7802_sysfs_get_min_conversions, + nau7802_sysfs_set_min_conversions, 0); + +static struct attribute *nau7802_attributes[] = { + &iio_const_attr_sampling_frequency_available.dev_attr.attr, + &iio_dev_attr_min_conversions.dev_attr.attr, + NULL +}; + +static const struct attribute_group nau7802_attribute_group = { + .attrs = nau7802_attributes, +}; + +static int nau7802_set_gain(struct nau7802_state *st, int gain) +{ + u8 data; + int ret; + + mutex_lock(&st->lock); + st->conversion_count = 0; + + data = i2c_smbus_read_byte_data(st->client, NAU7802_REG_CTRL1); + if (data < 0) + goto nau7802_sysfs_set_gain_out; + ret = i2c_smbus_write_byte_data(st->client, NAU7802_REG_CTRL1, + (data & (~NAU7802_CTRL1_GAINS_BITS)) | + gain); + +nau7802_sysfs_set_gain_out: + mutex_unlock(&st->lock); + + return ret ? ret : 0; +} + +static int nau7802_read_conversion(struct nau7802_state *st) +{ + u8 data; + + mutex_lock(&st->data_lock); + data = i2c_smbus_read_byte_data(st->client, NAU7802_REG_ADC_B2); + if (data < 0) + goto nau7802_read_conversion_out; + st->last_value = data << 16; + + data = i2c_smbus_read_byte_data(st->client, NAU7802_REG_ADC_B1); + if (data < 0) + goto nau7802_read_conversion_out; + st->last_value |= data << 8; + + data = i2c_smbus_read_byte_data(st->client, NAU7802_REG_ADC_B0); + if (data < 0) + goto nau7802_read_conversion_out; + st->last_value |= data; + + st->last_value = sign_extend32(st->last_value, 23); + +nau7802_read_conversion_out: + mutex_unlock(&st->data_lock); + + return data; +} + +/* + * Conversions are synchronised on the rising edge of NAU7802_PUCTRL_CS_BIT + */ +static int nau7802_sync(struct nau7802_state *st) +{ + int ret; + u8 data; + + data = i2c_smbus_read_byte_data(st->client, NAU7802_REG_PUCTRL); + if (data < 0) + return data; + ret = i2c_smbus_write_byte_data(st->client, NAU7802_REG_PUCTRL, + data | NAU7802_PUCTRL_CS_BIT); + + return ret; +} + +static irqreturn_t nau7802_eoc_trigger(int irq, void *private) +{ + struct iio_dev *indio_dev = private; + struct nau7802_state *st = iio_priv(indio_dev); + u8 status; + + status = i2c_smbus_read_byte_data(st->client, NAU7802_REG_PUCTRL); + if (status < 0) + return IRQ_HANDLED; + + if (!(status & NAU7802_PUCTRL_CR_BIT)) + return IRQ_NONE; + + if (nau7802_read_conversion(st) < 0) + return IRQ_HANDLED; + + /* Because there is actually only one ADC for both channels, we have to + * wait for enough conversions to happen before getting a significant + * value when changing channels and the values are far appart. + */ + if (st->conversion_count < st->min_conversions) + st->conversion_count++; + if (st->conversion_count >= st->min_conversions) + complete_all(&st->value_ok); + + return IRQ_HANDLED; +} + +static int nau7802_read_irq(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val) +{ + struct nau7802_state *st = iio_priv(indio_dev); + int ret; + + INIT_COMPLETION(st->value_ok); + enable_irq(st->client->irq); + + nau7802_sync(st); + + /* read registers to ensure we flush everything */ + ret = nau7802_read_conversion(st); + if (ret < 0) + goto read_chan_info_failure; + + /* Wait for a conversion to finish */ + ret = wait_for_completion_interruptible_timeout(&st->value_ok, + msecs_to_jiffies(1000)); + if (ret == 0) + ret = -ETIMEDOUT; + + if (ret < 0) + goto read_chan_info_failure; + + disable_irq(st->client->irq); + + *val = st->last_value; + + return IIO_VAL_INT; + +read_chan_info_failure: + disable_irq(st->client->irq); + + return ret; +} + +static int nau7802_read_poll(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val) +{ + struct nau7802_state *st = iio_priv(indio_dev); + int ret; + u8 data; + + nau7802_sync(st); + + /* read registers to ensure we flush everything */ + ret = nau7802_read_conversion(st); + if (ret < 0) + return ret; + + /* Because there is actually only one ADC for both channels, we have to + * wait for enough conversions to happen before getting a significant + * value when changing channels and the values are far appart. + */ + do { + data = i2c_smbus_read_byte_data(st->client, NAU7802_REG_PUCTRL); + if (data < 0) + return data; + + while (!(data & NAU7802_PUCTRL_CR_BIT)) { + if (st->sample_rate != NAU7802_SAMP_FREQ_320) + msleep(20); + else + mdelay(4); + data = i2c_smbus_read_byte_data(st->client, + NAU7802_REG_PUCTRL); + if (data < 0) + return data; + } + + nau7802_read_conversion(st); + if (ret < 0) + return ret; + if (st->conversion_count < st->min_conversions) + st->conversion_count++; + } while (st->conversion_count < st->min_conversions); + + *val = st->last_value; + + return IIO_VAL_INT; +} + +static int nau7802_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, int *val2, long mask) +{ + struct nau7802_state *st = iio_priv(indio_dev); + u8 data; + int ret; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + mutex_lock(&st->lock); + /* + * Select the channel to use + * - Channel 1 is value 0 in the CHS register + * - Channel 2 is value 1 in the CHS register + */ + data = i2c_smbus_read_byte_data(st->client, NAU7802_REG_CTRL2); + if (data < 0) + return data; + + if (((data & NAU7802_CTRL2_CHS_BIT) && !chan->channel) || + (!(data & NAU7802_CTRL2_CHS_BIT) && + chan->channel)) { + st->conversion_count = 0; + ret = i2c_smbus_write_byte_data(st->client, + NAU7802_REG_CTRL2, + NAU7802_CTRL2_CHS(chan->channel) | + NAU7802_CTRL2_CRS(st->sample_rate)); + + if (ret < 0) + return ret; + } + + if (st->client->irq) + ret = nau7802_read_irq(indio_dev, chan, val); + else + ret = nau7802_read_poll(indio_dev, chan, val); + + mutex_unlock(&st->lock); + return ret; + + case IIO_CHAN_INFO_SCALE: + data = i2c_smbus_read_byte_data(st->client, NAU7802_REG_CTRL1); + if (data < 0) + return data; + + /* we have 24 bits of signed data, that means 23 bits of data + * plus the sign bit */ + *val = st->vref_mv; + *val2 = 23 + (data & NAU7802_CTRL1_GAINS_BITS); + + return IIO_VAL_FRACTIONAL_LOG2; + + case IIO_CHAN_INFO_SAMP_FREQ: + *val = nau7802_sample_freq_avail[st->sample_rate]; + *val2 = 0; + return IIO_VAL_INT; + + default: + break; + } + + return -EINVAL; +} + +static int nau7802_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, int val2, long mask) +{ + struct nau7802_state *st = iio_priv(indio_dev); + int i; + + switch (mask) { + case IIO_CHAN_INFO_SCALE: + for (i = 0; i < ARRAY_SIZE(st->scale_avail); i++) + if (val2 == st->scale_avail[i]) + return nau7802_set_gain(st, i); + + break; + + case IIO_CHAN_INFO_SAMP_FREQ: + for (i = 0; i < ARRAY_SIZE(nau7802_sample_freq_avail); i++) + if (val == nau7802_sample_freq_avail[i]) { + mutex_lock(&st->lock); + st->sample_rate = i; + st->conversion_count = 0; + i2c_smbus_write_byte_data(st->client, + NAU7802_REG_CTRL2, + NAU7802_CTRL2_CRS(st->sample_rate)); + mutex_unlock(&st->lock); + return 0; + } + + break; + + default: + break; + } + + return -EINVAL; +} + +static int nau7802_write_raw_get_fmt(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + long mask) +{ + return IIO_VAL_INT_PLUS_NANO; +} + +static const struct iio_info nau7802_info = { + .driver_module = THIS_MODULE, + .read_raw = &nau7802_read_raw, + .write_raw = &nau7802_write_raw, + .write_raw_get_fmt = nau7802_write_raw_get_fmt, + .attrs = &nau7802_attribute_group, +}; + +static int nau7802_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct iio_dev *indio_dev; + struct nau7802_state *st; + struct device_node *np = client->dev.of_node; + int i, ret; + u8 data; + u32 tmp; + + if (!client->dev.of_node) { + dev_err(&client->dev, "No device tree node available.\n"); + return -EINVAL; + } + + indio_dev = iio_device_alloc(sizeof(*st)); + if (indio_dev == NULL) + return -ENOMEM; + + st = iio_priv(indio_dev); + + i2c_set_clientdata(client, indio_dev); + + indio_dev->dev.parent = &client->dev; + indio_dev->name = dev_name(&client->dev); + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->info = &nau7802_info; + + st->client = client; + + /* Reset the device */ + i2c_smbus_write_byte_data(st->client, NAU7802_REG_PUCTRL, + NAU7802_PUCTRL_RR_BIT); + + /* Enter normal operation mode */ + i2c_smbus_write_byte_data(st->client, NAU7802_REG_PUCTRL, + NAU7802_PUCTRL_PUD_BIT); + + /* + * After about 200 usecs, the device should be ready and then + * the Power Up bit will be set to 1. If not, wait for it. + */ + udelay(210); + data = i2c_smbus_read_byte_data(st->client, NAU7802_REG_PUCTRL); + if (data < 0) + return -ENODEV; + if (!(data & NAU7802_PUCTRL_PUR_BIT)) + return -ENODEV; + + of_property_read_u32(np, "nuvoton,vldo", &tmp); + st->vref_mv = tmp; + + /* Populate available ADC input ranges */ + for (i = 0; i < ARRAY_SIZE(st->scale_avail); i++) + st->scale_avail[i] = (((u64)st->vref_mv) * 1000000000ULL) + >> (23 + i); + + data = NAU7802_PUCTRL_PUD_BIT | NAU7802_PUCTRL_PUA_BIT | + NAU7802_PUCTRL_CS_BIT; + if (tmp >= 2400) + data |= NAU7802_PUCTRL_AVDDS_BIT; + + i2c_smbus_write_byte_data(st->client, NAU7802_REG_PUCTRL, data); + i2c_smbus_write_byte_data(st->client, NAU7802_REG_ADC_CTRL, 0x30); + + if (tmp >= 2400) { + data = NAU7802_CTRL1_VLDO((4500 - tmp) / 300); + i2c_smbus_write_byte_data(st->client, NAU7802_REG_CTRL1, data); + } + + st->min_conversions = NAU7802_DEFAULT_CONVERSIONS; + + /* + * The ADC fires continuously and we can't do anything about + * it. So we need to have the IRQ disabled by default, and we + * will enable them back when we will need them.. + */ + if (client->irq) { + ret = request_threaded_irq(client->irq, + NULL, + nau7802_eoc_trigger, + IRQF_TRIGGER_HIGH | IRQF_ONESHOT, + client->dev.driver->name, + indio_dev); + if (ret) { + /* + * What may happen here is that our IRQ controller is + * not able to get level interrupt but this is required + * by this ADC as when going over 40 sample per second, + * the interrupt line may stay high between conversions. + * So, we continue no matter what but we switch to + * polling mode. + */ + dev_info(&client->dev, + "Failed to allocate IRQ, using polling mode\n"); + client->irq = 0; + } else + disable_irq(client->irq); + } + + if (!client->irq) { + /* + * We are polling, use the fastest sample rate by + * default + */ + st->sample_rate = NAU7802_SAMP_FREQ_320; + i2c_smbus_write_byte_data(st->client, NAU7802_REG_CTRL2, + NAU7802_CTRL2_CRS(st->sample_rate)); + } + + /* Setup the ADC channels available on the board */ + indio_dev->num_channels = 2; + indio_dev->channels = nau7802_chan_array; + + init_completion(&st->value_ok); + mutex_init(&st->lock); + mutex_init(&st->data_lock); + + ret = iio_device_register(indio_dev); + if (ret < 0) { + dev_err(&client->dev, "Couldn't register the device.\n"); + goto error_device_register; + } + + return 0; + +error_device_register: + mutex_destroy(&st->lock); + mutex_destroy(&st->data_lock); + if (client->irq) + free_irq(client->irq, indio_dev); + iio_device_free(indio_dev); + + return ret; +} + +static int nau7802_remove(struct i2c_client *client) +{ + struct iio_dev *indio_dev = i2c_get_clientdata(client); + struct nau7802_state *st = iio_priv(indio_dev); + + iio_device_unregister(indio_dev); + mutex_destroy(&st->lock); + mutex_destroy(&st->data_lock); + if (client->irq) + free_irq(client->irq, indio_dev); + iio_device_free(indio_dev); + + return 0; +} + +static const struct i2c_device_id nau7802_i2c_id[] = { + { "nau7802", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, nau7802_i2c_id); + +static const struct of_device_id nau7802_dt_ids[] = { + { .compatible = "nuvoton,nau7802" }, + {}, +}; +MODULE_DEVICE_TABLE(of, nau7802_dt_ids); + +static struct i2c_driver nau7802_driver = { + .probe = nau7802_probe, + .remove = nau7802_remove, + .id_table = nau7802_i2c_id, + .driver = { + .name = "nau7802", + .of_match_table = of_match_ptr(nau7802_dt_ids), + }, +}; + +module_i2c_driver(nau7802_driver); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Nuvoton NAU7802 ADC Driver"); +MODULE_AUTHOR("Maxime Ripard "); +MODULE_AUTHOR("Alexandre Belloni ");