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([2600:8803:e7e4:500:359b:17f1:d4f9:4949]) by smtp.gmail.com with ESMTPSA id 586e51a60fabf-458f664d884sm4232455fac.12.2026.08.01.09.05.32 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sat, 01 Aug 2026 09:05:33 -0700 (PDT) Message-ID: <3688ba60-3ff3-4e61-81a5-c220afaef66f@baylibre.com> Date: Sat, 1 Aug 2026 11:05:31 -0500 Precedence: bulk X-Mailing-List: linux-hwmon@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v6 2/2] iio: adc: add MAX40080 current-sense amplifier driver To: Stefan Popa , linux-iio@vger.kernel.org Cc: linux-hwmon@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, jic23@kernel.org, andy@kernel.org, nuno.sa@analog.com, linux@roeck-us.net, robh@kernel.org, krzk+dt@kernel.org, conor+dt@kernel.org, ciprian.hegbeli@analog.com, siratul.islam@linux.dev, u.kleine-koenig@baylibre.com, joshua.crofts1@gmail.com References: <20260730131738.822405-1-stefan.popa@analog.com> <20260730131738.822405-3-stefan.popa@analog.com> Content-Language: en-US From: David Lechner In-Reply-To: <20260730131738.822405-3-stefan.popa@analog.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 7/30/26 8:17 AM, Stefan Popa wrote: > The MAX40080 is a bidirectional current-sense amplifier with an > integrated 12-bit ADC and an I2C/SMBus interface. It measures the > voltage across an external shunt resistor and the input bus voltage, > storing the results in an internal FIFO. > > Add a direct-mode IIO driver exposing the current and voltage channels > with raw, scale and hardware-gain attributes, a configurable > oversampling (digital averaging) ratio, and PEC-protected register > access. The current scale is derived from the shunt resistor value > described in the device tree. > > The driver operates in single-measurement mode: each raw read triggers > an on-demand conversion via SMBus Quick Command and returns a matched > current/voltage pair. This avoids the latency and complexity of the > continuous FIFO mode while ensuring each read reflects the current > state. The two selectable current-sense ranges are exposed through > scale/scale_available. > > Continuous FIFO buffering, threshold events and the alert interrupt are > intentionally left out of this initial submission and may be added > later. > > Co-developed-by: Ciprian Hegbeli > Signed-off-by: Ciprian Hegbeli > Signed-off-by: Stefan Popa > --- > MAINTAINERS | 1 + > drivers/iio/adc/Kconfig | 11 + > drivers/iio/adc/Makefile | 1 + > drivers/iio/adc/max40080.c | 574 +++++++++++++++++++++++++++++++++++++ > 4 files changed, 587 insertions(+) > create mode 100644 drivers/iio/adc/max40080.c > > diff --git a/MAINTAINERS b/MAINTAINERS > index e1170230c4bb2..467e6bbf72cde 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -28901,3 +28901,4 @@ L: linux-iio@vger.kernel.org > S: Supported > W: https://ez.analog.com/linux-software-drivers > F: Documentation/devicetree/bindings/iio/adc/adi,max40080.yaml > +F: drivers/iio/adc/max40080.c > diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig > index 58da8255525e4..ebdbad81fbbd6 100644 > --- a/drivers/iio/adc/Kconfig > +++ b/drivers/iio/adc/Kconfig > @@ -1907,3 +1907,14 @@ config XILINX_AMS > xilinx-ams. > > endmenu > + > +config MAX40080 > + tristate "Analog Devices MAX40080 Current Sense Amplifier" > + depends on I2C > + help > + Say yes here to build support for the Analog Devices MAX40080 > + bidirectional current-sense amplifier with a 12-bit ADC and an I2C > + interface. > + > + To compile this driver as a module, choose M here: the module will be > + called max40080. > diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile > index 7cc8f9a12f763..9245a337dd935 100644 > --- a/drivers/iio/adc/Makefile > +++ b/drivers/iio/adc/Makefile > @@ -166,3 +166,4 @@ obj-$(CONFIG_VIPERBOARD_ADC) += viperboard_adc.o > obj-$(CONFIG_XILINX_AMS) += xilinx-ams.o > xilinx-xadc-y := xilinx-xadc-core.o xilinx-xadc-events.o > obj-$(CONFIG_XILINX_XADC) += xilinx-xadc.o > +obj-$(CONFIG_MAX40080) += max40080.o > diff --git a/drivers/iio/adc/max40080.c b/drivers/iio/adc/max40080.c > new file mode 100644 > index 0000000000000..82572536b704d > --- /dev/null > +++ b/drivers/iio/adc/max40080.c > @@ -0,0 +1,574 @@ > +// SPDX-License-Identifier: GPL-2.0+ > +/* > + * MAX40080 Digital Current-Sense Amplifier driver > + * > + * Copyright 2026 Analog Devices, Inc. > + * > + * Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/MAX40080.pdf > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +#include > + > +#define MAX40080_REG_CFG 0x00 > +#define MAX40080_CFG_MODE_MSK GENMASK(2, 0) > +#define MAX40080_CFG_PEC_EN_MSK BIT(5) > +#define MAX40080_CFG_RANGE_MSK BIT(6) > +#define MAX40080_CFG_FILTER_MSK GENMASK(14, 12) > + > +#define MAX40080_REG_FIFO_CFG 0x0A > +#define MAX40080_FIFO_CFG_STORE_IV_MSK GENMASK(1, 0) > + > +#define MAX40080_REG_IV 0x10 > +/* Current is a 13-bit two's-complement value (magnitude + sign bit). */ > +#define MAX40080_IV_I_MSK GENMASK(12, 0) > +#define MAX40080_IV_I_SIGN_BIT 12 > +#define MAX40080_IV_V_MAG_MSK GENMASK(27, 16) > +#define MAX40080_IV_VALID_MSK BIT(31) > + > +/* CFG.mode field values. */ > +#define MAX40080_CFG_MODE_STDBY 0x00 > +#define MAX40080_CFG_MODE_SINGLE 0x02 > + > +/* CFG.range field values. */ > +#define MAX40080_CFG_RANGE_50MV 0 > +#define MAX40080_CFG_RANGE_10MV 1 > + > +/* FIFO_CFG.store_iv field values. */ > +#define MAX40080_FIFO_CFG_STORE_I_V 0x02 > + > +#define MAX40080_ADC_RES_BITS 12 > +#define MAX40080_INTER_VREF_MV 1250 > +#define MAX40080_V_BUFF_GAIN 30 > +#define MAX40080_CSA_50MV_GAIN 25 > +#define MAX40080_CSA_10MV_GAIN 125 > + > +/* > + * The RANGE field (CFG bit 6) selects one of two current-sense full-scale > + * ranges (the MAX40080 supports exactly two: +/-50 mV and +/-10 mV). Indexed > + * by the CFG.range field value. > + */ > +static const int max40080_csa_gain[] = { > + [MAX40080_CFG_RANGE_50MV] = MAX40080_CSA_50MV_GAIN, > + [MAX40080_CFG_RANGE_10MV] = MAX40080_CSA_10MV_GAIN, > +}; > + > +#define MAX40080_NUM_RANGES ARRAY_SIZE(max40080_csa_gain) > + > +struct max40080_state { > + struct i2c_client *client; > + /* Serializes read-modify-write access to the CFG register. */ > + struct mutex lock; > + u32 shunt_resistor_uohm; > + /* Cached configuration: the selected RANGE index and oversampling ratio. */ > + unsigned int range; > + int oversampling_ratio; > + /* > + * Precomputed current scale (mA per code) for each RANGE setting, as > + * {integer, nano} pairs for IIO_VAL_INT_PLUS_NANO. The range is > + * selected by writing the corresponding scale. > + */ > + int current_scale[MAX40080_NUM_RANGES][2]; > +}; > + > +static const int max40080_oversampling_avail[] = { 1, 8, 16, 32, 64, 128 }; > + > +static int max40080_update_bits(struct max40080_state *st, u8 reg, > + u16 mask, u16 val) > +{ > + int tmp; > + > + tmp = i2c_smbus_read_word_data(st->client, reg); > + if (tmp < 0) > + return tmp; > + > + tmp = (tmp & ~mask) | (val & mask); > + > + return i2c_smbus_write_word_data(st->client, reg, tmp); > +} > + > +/* > + * In single-measurement mode the device sits idle until it receives an SMBus > + * Quick Command, then performs exactly one current and one voltage conversion > + * and returns to idle. Triggering on demand this way (rather than running the > + * FIFO continuously in active mode) means each read returns a fresh, coherent > + * current/voltage pair instead of the oldest queued FIFO entry. > + */ > +static int max40080_trigger_measurement(struct max40080_state *st) > +{ > + return i2c_smbus_xfer(st->client->adapter, st->client->addr, > + st->client->flags, I2C_SMBUS_WRITE, 0, > + I2C_SMBUS_QUICK, NULL); > +} > + > +/* > + * A single measurement holds the matched current/voltage pair in one 32-bit > + * word (MAX40080_REG_IV). Reading all four bytes in one transaction returns > + * both from the same conversion; reading the separate current (0x0C) and > + * voltage (0x0E) registers would decorrelate the two channels. > + * > + * Unlike the word accesses used elsewhere, this is a plain I2C block read: the > + * SMBus layer does not append or verify a PEC byte for it even when PEC is > + * otherwise enabled for the device, so this transfer is not PEC protected. > + */ > +static int max40080_read_iv_once(struct max40080_state *st, u32 *iv) > +{ > + u8 buf[4]; > + int ret; > + > + ret = i2c_smbus_read_i2c_block_data(st->client, MAX40080_REG_IV, > + sizeof(buf), buf); > + if (ret < 0) > + return ret; > + if (ret != sizeof(buf)) > + return -EIO; This can't return anything other than negative error or sizeof(buf), so this is dead code. > + > + *iv = get_unaligned_le32(buf); > + > + return 0; > +} > + > +static int max40080_read_iv(struct max40080_state *st, u32 *iv) > +{ > + u32 tmp = 0; initializing tmp is dead code. > + int ret, io_ret; > + > + guard(mutex)(&st->lock); > + > + ret = max40080_trigger_measurement(st); > + if (ret < 0) > + return ret; > + > + /* > + * Wait for the conversion to complete by polling the FIFO valid bit > + * (or bail out on an I2C error). Polling the device's own status makes > + * this independent of the actual conversion time, which varies with the > + * oversampling ratio and the bus speed. The timeout is only a safety > + * ceiling: the worst case is the maximum 128x averaging on both the > + * current and voltage channels at the slowest 15 ksps base rate plus the > + * inter-channel switching time, i.e. roughly 20 ms; 50 ms leaves ample > + * margin. > + */ > + ret = read_poll_timeout(max40080_read_iv_once, io_ret, > + io_ret || (tmp & MAX40080_IV_VALID_MSK), > + 500, 50000, false, st, &tmp); > + /* > + * Propagate the last-read value even on timeout so the caller can > + * inspect it for debugging. > + */ > + *iv = tmp; > + if (ret) > + return ret; > + > + return io_ret; > +} > + > +static int max40080_get_current(struct max40080_state *st, int *val) > +{ > + u32 iv = 0; don't need to init here either. > + int ret; > + > + ret = max40080_read_iv(st, &iv); > + if (ret) > + return ret; > + > + *val = sign_extend32(FIELD_GET(MAX40080_IV_I_MSK, iv), > + MAX40080_IV_I_SIGN_BIT); > + > + return 0; > +} > + > +static int max40080_get_voltage(struct max40080_state *st, int *val) > +{ > + u32 iv = 0; > + int ret; > + > + ret = max40080_read_iv(st, &iv); > + if (ret) > + return ret; > + > + *val = FIELD_GET(MAX40080_IV_V_MAG_MSK, iv); > + > + return 0; > +} > + > +static int max40080_set_range(struct max40080_state *st, unsigned int range) > +{ > + int ret; > + > + ret = max40080_update_bits(st, MAX40080_REG_CFG, MAX40080_CFG_RANGE_MSK, > + FIELD_PREP(MAX40080_CFG_RANGE_MSK, range)); > + if (ret) > + return ret; > + > + st->range = range; > + > + return 0; > +} > + > +/* > + * Precompute the current scale (mA per code) for each RANGE setting as > + * {integer, nano} pairs. The shunt drop for a full-scale code is > + * Vref[mV] / ((1 << ADC_RES_BITS) * gain) > + * and current = Vshunt / Rshunt, so with Rshunt in micro-ohms the scale in > + * mA/code is > + * Vref[mV] * NANO * MICRO / ((1 << ADC_RES_BITS) * gain * Rshunt[uohm]) > + * expressed as an integer part plus a nano fractional part. > + */ > +static void max40080_calc_current_scale(struct max40080_state *st) > +{ > + u32 rem; > + u64 tmp; > + > + for (unsigned int i = 0; i < MAX40080_NUM_RANGES; i++) { > + tmp = (u64)MAX40080_INTER_VREF_MV * NANO * MICRO; > + tmp = div64_u64(tmp, (u64)(1 << MAX40080_ADC_RES_BITS) * max40080_csa_gain[i] * BIT(MAX40080_ADC_RES_BITS) > + st->shunt_resistor_uohm); > + st->current_scale[i][0] = div_u64_rem(tmp, NANO, &rem); > + st->current_scale[i][1] = rem; > + } > +} > + > +/* > + * max40080_oversampling_avail[] is ordered so that its index is the FILTER > + * field value (index 0 = no averaging, index 1 = 8x, ...). Return that index > + * for an exact match, or -EINVAL for a value that is not on the list. > + */ > +static int max40080_oversampling_to_filter(int val) > +{ > + for (unsigned int i = 0; i < ARRAY_SIZE(max40080_oversampling_avail); i++) { > + if (max40080_oversampling_avail[i] == val) > + return i; > + } > + > + return -EINVAL; > +} > + > +static int max40080_set_oversampling_ratio(struct max40080_state *st, int val) > +{ > + int filter; > + int ret; > + > + filter = max40080_oversampling_to_filter(val); > + if (filter < 0) > + return filter; > + > + ret = max40080_update_bits(st, MAX40080_REG_CFG, MAX40080_CFG_FILTER_MSK, > + FIELD_PREP(MAX40080_CFG_FILTER_MSK, filter)); > + if (ret) > + return ret; > + > + st->oversampling_ratio = val; > + > + return 0; > +} > + > +static int max40080_read_raw(struct iio_dev *indio_dev, > + struct iio_chan_spec const *chan, > + int *val, int *val2, long mask) > +{ > + struct max40080_state *st = iio_priv(indio_dev); > + unsigned int range; > + int ret; > + > + switch (mask) { > + case IIO_CHAN_INFO_RAW: > + if (chan->type == IIO_CURRENT) { > + ret = max40080_get_current(st, val); > + if (ret) > + return ret; > + } else if (chan->type == IIO_VOLTAGE) { > + ret = max40080_get_voltage(st, val); > + if (ret) > + return ret; > + } Looks like this could be a switch statement. > + return IIO_VAL_INT; > + case IIO_CHAN_INFO_SCALE: > + if (chan->type == IIO_CURRENT) { > + /* > + * The selectable current-sense range is exposed through > + * scale: each RANGE setting has its own precomputed > + * mA-per-code value. Userspace picks the range by writing > + * the matching scale. > + * > + * Take a local copy of range to ensure val and val2 come > + * from the same setting even if a concurrent write changes > + * st->range between the two accesses. > + */ > + range = st->range; Local range variable is adding more characters than it saves. Not really needed IMHO. > + *val = st->current_scale[range][0]; > + *val2 = st->current_scale[range][1]; > + return IIO_VAL_INT_PLUS_NANO; > + } > + /* voltage[mV] = raw * Vref[mV] * buffer_gain / (1 << ADC_RES_BITS) */ > + *val = MAX40080_INTER_VREF_MV * MAX40080_V_BUFF_GAIN; > + *val2 = MAX40080_ADC_RES_BITS; > + return IIO_VAL_FRACTIONAL_LOG2; > + case IIO_CHAN_INFO_OVERSAMPLING_RATIO: > + *val = st->oversampling_ratio; > + return IIO_VAL_INT; > + default: > + return -EINVAL; > + } > +} > + > +static int max40080_write_raw(struct iio_dev *indio_dev, > + struct iio_chan_spec const *chan, > + int val, int val2, long mask) > +{ > + struct max40080_state *st = iio_priv(indio_dev); > + > + guard(mutex)(&st->lock); > + > + switch (mask) { > + case IIO_CHAN_INFO_SCALE: > + /* Only the current channel has a selectable range/scale. */ > + if (chan->type != IIO_CURRENT) > + return -EINVAL; > + > + for (unsigned int i = 0; i < MAX40080_NUM_RANGES; i++) { > + if (val == st->current_scale[i][0] && > + val2 == st->current_scale[i][1]) > + return max40080_set_range(st, i); > + } > + > + return -EINVAL; > + case IIO_CHAN_INFO_OVERSAMPLING_RATIO: > + return max40080_set_oversampling_ratio(st, val); > + default: > + return -EINVAL; > + } > +} > + > +static int max40080_write_raw_get_fmt(struct iio_dev *indio_dev, > + struct iio_chan_spec const *chan, > + long mask) > +{ > + switch (mask) { > + case IIO_CHAN_INFO_SCALE: > + return IIO_VAL_INT_PLUS_NANO; > + default: > + return IIO_VAL_INT; > + } > +} > + > +static int max40080_read_avail(struct iio_dev *indio_dev, > + struct iio_chan_spec const *chan, > + const int **vals, int *type, int *length, > + long info) > +{ > + struct max40080_state *st = iio_priv(indio_dev); > + > + switch (info) { > + case IIO_CHAN_INFO_SCALE: > + if (chan->type != IIO_CURRENT) > + return -EINVAL; > + > + *vals = (int *)st->current_scale; > + *length = MAX40080_NUM_RANGES * 2; > + *type = IIO_VAL_INT_PLUS_NANO; > + return IIO_AVAIL_LIST; > + case IIO_CHAN_INFO_OVERSAMPLING_RATIO: > + *vals = max40080_oversampling_avail; > + *length = ARRAY_SIZE(max40080_oversampling_avail); > + *type = IIO_VAL_INT; > + return IIO_AVAIL_LIST; > + default: > + return -EINVAL; > + } > +} > + > +static int max40080_reg_access(struct iio_dev *indio_dev, unsigned int reg, > + unsigned int write_val, unsigned int *read_val) > +{ > + struct max40080_state *st = iio_priv(indio_dev); > + int val; > + No range checking on reg? > + if (read_val) { > + val = i2c_smbus_read_word_data(st->client, reg); > + if (val < 0) > + return val; > + > + *read_val = val; > + > + return 0; > + } > + > + return i2c_smbus_write_word_data(st->client, reg, write_val); > +} > + > +static const struct iio_info max40080_info = { > + .read_raw = max40080_read_raw, > + .write_raw = max40080_write_raw, > + .write_raw_get_fmt = max40080_write_raw_get_fmt, > + .read_avail = max40080_read_avail, > + .debugfs_reg_access = &max40080_reg_access, > +}; > + > +static const struct iio_chan_spec max40080_channels[] = { > + { > + .type = IIO_CURRENT, > + .indexed = 1, > + .channel = 0, > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | > + BIT(IIO_CHAN_INFO_SCALE), > + .info_mask_separate_available = BIT(IIO_CHAN_INFO_SCALE), > + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), > + .info_mask_shared_by_all_available = > + BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), > + }, > + { > + .type = IIO_VOLTAGE, > + .indexed = 1, > + .channel = 0, > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | > + BIT(IIO_CHAN_INFO_SCALE), > + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), > + .info_mask_shared_by_all_available = > + BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), > + }, > +}; > + > +/* > + * Configure the device from the cached state. The device powers up in standby > + * with PEC enabled (CFG POR = 0x0060), so PEC is kept enabled throughout. > + */ > +static int max40080_init(struct max40080_state *st) > +{ > + u16 fifo_cfg, cfg; > + int ret, filter; > + > + filter = max40080_oversampling_to_filter(st->oversampling_ratio); > + if (filter < 0) > + return filter; > + > + /* > + * Put the device in standby before (re)configuring the FIFO: the FIFO > + * configuration register can only be written while the device is not > + * converting. > + */ > + cfg = FIELD_PREP(MAX40080_CFG_MODE_MSK, MAX40080_CFG_MODE_STDBY) | > + FIELD_PREP(MAX40080_CFG_PEC_EN_MSK, 1); > + > + ret = i2c_smbus_write_word_data(st->client, MAX40080_REG_CFG, cfg); > + if (ret) > + return ret; > + > + /* Store a matched current+voltage pair per conversion. */ > + fifo_cfg = FIELD_PREP(MAX40080_FIFO_CFG_STORE_IV_MSK, MAX40080_FIFO_CFG_STORE_I_V); > + > + ret = i2c_smbus_write_word_data(st->client, MAX40080_REG_FIFO_CFG, > + fifo_cfg); > + if (ret) > + return ret; > + > + /* > + * Use single-measurement mode: the device stays idle and converts once > + * per SMBus Quick Command (see max40080_trigger_measurement()), so each > + * read returns a fresh sample rather than a queued FIFO entry. > + */ > + cfg = FIELD_PREP(MAX40080_CFG_MODE_MSK, MAX40080_CFG_MODE_SINGLE) | > + FIELD_PREP(MAX40080_CFG_PEC_EN_MSK, 1) | > + FIELD_PREP(MAX40080_CFG_RANGE_MSK, st->range) | > + FIELD_PREP(MAX40080_CFG_FILTER_MSK, filter); > + > + return i2c_smbus_write_word_data(st->client, MAX40080_REG_CFG, cfg); > +} > + > +static int max40080_probe(struct i2c_client *client) > +{ > + const char *propname = "shunt-resistor-micro-ohms"; > + struct device *dev = &client->dev; > + struct iio_dev *indio_dev; > + struct max40080_state *st; > + int ret; > + > + /* > + * The device powers up with PEC enabled (CFG POR = 0x0060) and rejects > + * unprotected transactions, so PEC support is mandatory, along with word > + * access, the I2C block read used for the current/voltage pair, and the > + * Quick Command used to trigger a conversion. > + */ > + if (!i2c_check_functionality(client->adapter, > + I2C_FUNC_SMBUS_WORD_DATA | > + I2C_FUNC_SMBUS_I2C_BLOCK | > + I2C_FUNC_SMBUS_QUICK | > + I2C_FUNC_SMBUS_PEC)) > + return -EOPNOTSUPP; > + > + client->flags |= I2C_CLIENT_PEC; > + > + indio_dev = devm_iio_device_alloc(dev, sizeof(*st)); > + if (!indio_dev) > + return -ENOMEM; > + > + st = iio_priv(indio_dev); > + st->client = client; > + > + ret = devm_mutex_init(dev, &st->lock); > + if (ret) > + return ret; > + Assign propname here so we don't have to scroll to see what it is. > + ret = device_property_read_u32(dev, propname, &st->shunt_resistor_uohm); > + if (ret) > + return dev_err_probe(dev, ret, "can't read %s\n", propname); > + if (!st->shunt_resistor_uohm) > + return dev_err_probe(dev, -EINVAL, "%s must be non-zero\n", > + propname); > + > + max40080_calc_current_scale(st); > + > + /* Defaults: 50 mV range, no averaging. */ > + st->range = MAX40080_CFG_RANGE_50MV; > + st->oversampling_ratio = 1; > + > + indio_dev->name = "max40080"; > + indio_dev->info = &max40080_info; > + indio_dev->modes = INDIO_DIRECT_MODE; > + indio_dev->channels = max40080_channels; > + indio_dev->num_channels = ARRAY_SIZE(max40080_channels); > + > + ret = max40080_init(st); > + if (ret) > + return ret; > + > + return devm_iio_device_register(dev, indio_dev); > +} > + > +static const struct i2c_device_id max40080_i2c_ids[] = { > + { .name = "max40080" }, > + { } > +}; > +MODULE_DEVICE_TABLE(i2c, max40080_i2c_ids); > + > +static const struct of_device_id max40080_of_match[] = { > + { .compatible = "adi,max40080" }, > + { } > +}; > +MODULE_DEVICE_TABLE(of, max40080_of_match); > + > +static struct i2c_driver max40080_driver = { > + .driver = { > + .name = "max40080", > + .of_match_table = max40080_of_match, > + }, > + .probe = max40080_probe, > + .id_table = max40080_i2c_ids, > +}; > +module_i2c_driver(max40080_driver); > + > +MODULE_AUTHOR("Ciprian Hegbeli "); > +MODULE_AUTHOR("Stefan Popa "); > +MODULE_DESCRIPTION("Analog Devices MAX40080 current-sense amplifier driver"); > +MODULE_LICENSE("GPL");