diff options
Diffstat (limited to 'drivers/iio/cdc')
| -rw-r--r-- | drivers/iio/cdc/Kconfig | 27 | ||||
| -rw-r--r-- | drivers/iio/cdc/Makefile | 7 | ||||
| -rw-r--r-- | drivers/iio/cdc/ad7150.c | 657 | ||||
| -rw-r--r-- | drivers/iio/cdc/ad7746.c | 819 |
4 files changed, 1510 insertions, 0 deletions
diff --git a/drivers/iio/cdc/Kconfig b/drivers/iio/cdc/Kconfig new file mode 100644 index 0000000000..e0a5ce66a9 --- /dev/null +++ b/drivers/iio/cdc/Kconfig @@ -0,0 +1,27 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# CDC drivers +# +menu "Capacitance to digital converters" + +config AD7150 + tristate "Analog Devices ad7150/1/6 capacitive sensor driver" + depends on I2C + help + Say yes here to build support for Analog Devices capacitive sensors. + (ad7150, ad7151, ad7156) Provides direct access via sysfs. + + To compile this driver as a module, choose M here: the + module will be called ad7150. + +config AD7746 + tristate "Analog Devices AD7745, AD7746 AD7747 capacitive sensor driver" + depends on I2C + help + Say yes here to build support for Analog Devices capacitive sensors. + (AD7745, AD7746, AD7747) Provides direct access via sysfs. + + To compile this driver as a module, choose M here: the + module will be called ad7746. + +endmenu diff --git a/drivers/iio/cdc/Makefile b/drivers/iio/cdc/Makefile new file mode 100644 index 0000000000..41db756d80 --- /dev/null +++ b/drivers/iio/cdc/Makefile @@ -0,0 +1,7 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# Makefile for industrial I/O capacitance to digital converter (CDC) drivers +# + +obj-$(CONFIG_AD7150) += ad7150.o +obj-$(CONFIG_AD7746) += ad7746.o diff --git a/drivers/iio/cdc/ad7150.c b/drivers/iio/cdc/ad7150.c new file mode 100644 index 0000000000..4c03b9e834 --- /dev/null +++ b/drivers/iio/cdc/ad7150.c @@ -0,0 +1,657 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * AD7150 capacitive sensor driver supporting AD7150/1/6 + * + * Copyright 2010-2011 Analog Devices Inc. + * Copyright 2021 Jonathan Cameron <Jonathan.Cameron@huawei.com> + */ + +#include <linux/bitfield.h> +#include <linux/device.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/i2c.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/mod_devicetable.h> +#include <linux/regulator/consumer.h> +#include <linux/slab.h> + +#include <linux/iio/iio.h> +#include <linux/iio/sysfs.h> +#include <linux/iio/events.h> + +#define AD7150_STATUS_REG 0 +#define AD7150_STATUS_OUT1 BIT(3) +#define AD7150_STATUS_OUT2 BIT(5) +#define AD7150_CH1_DATA_HIGH_REG 1 +#define AD7150_CH2_DATA_HIGH_REG 3 +#define AD7150_CH1_AVG_HIGH_REG 5 +#define AD7150_CH2_AVG_HIGH_REG 7 +#define AD7150_CH1_SENSITIVITY_REG 9 +#define AD7150_CH1_THR_HOLD_H_REG 9 +#define AD7150_CH1_TIMEOUT_REG 10 +#define AD7150_CH_TIMEOUT_RECEDING GENMASK(3, 0) +#define AD7150_CH_TIMEOUT_APPROACHING GENMASK(7, 4) +#define AD7150_CH1_SETUP_REG 11 +#define AD7150_CH2_SENSITIVITY_REG 12 +#define AD7150_CH2_THR_HOLD_H_REG 12 +#define AD7150_CH2_TIMEOUT_REG 13 +#define AD7150_CH2_SETUP_REG 14 +#define AD7150_CFG_REG 15 +#define AD7150_CFG_FIX BIT(7) +#define AD7150_CFG_THRESHTYPE_MSK GENMASK(6, 5) +#define AD7150_CFG_TT_NEG 0x0 +#define AD7150_CFG_TT_POS 0x1 +#define AD7150_CFG_TT_IN_WINDOW 0x2 +#define AD7150_CFG_TT_OUT_WINDOW 0x3 +#define AD7150_PD_TIMER_REG 16 +#define AD7150_CH1_CAPDAC_REG 17 +#define AD7150_CH2_CAPDAC_REG 18 +#define AD7150_SN3_REG 19 +#define AD7150_SN2_REG 20 +#define AD7150_SN1_REG 21 +#define AD7150_SN0_REG 22 +#define AD7150_ID_REG 23 + +enum { + AD7150, + AD7151, +}; + +/** + * struct ad7150_chip_info - instance specific chip data + * @client: i2c client for this device + * @threshold: thresholds for simple capacitance value events + * @thresh_sensitivity: threshold for simple capacitance offset + * from 'average' value. + * @thresh_timeout: a timeout, in samples from the moment an + * adaptive threshold event occurs to when the average + * value jumps to current value. Note made up of two fields, + * 3:0 are for timeout receding - applies if below lower threshold + * 7:4 are for timeout approaching - applies if above upper threshold + * @state_lock: ensure consistent state of this structure wrt the + * hardware. + * @interrupts: one or two interrupt numbers depending on device type. + * @int_enabled: is a given interrupt currently enabled. + * @type: threshold type + * @dir: threshold direction + */ +struct ad7150_chip_info { + struct i2c_client *client; + u16 threshold[2][2]; + u8 thresh_sensitivity[2][2]; + u8 thresh_timeout[2][2]; + struct mutex state_lock; + int interrupts[2]; + bool int_enabled[2]; + enum iio_event_type type; + enum iio_event_direction dir; +}; + +static const u8 ad7150_addresses[][6] = { + { AD7150_CH1_DATA_HIGH_REG, AD7150_CH1_AVG_HIGH_REG, + AD7150_CH1_SETUP_REG, AD7150_CH1_THR_HOLD_H_REG, + AD7150_CH1_SENSITIVITY_REG, AD7150_CH1_TIMEOUT_REG }, + { AD7150_CH2_DATA_HIGH_REG, AD7150_CH2_AVG_HIGH_REG, + AD7150_CH2_SETUP_REG, AD7150_CH2_THR_HOLD_H_REG, + AD7150_CH2_SENSITIVITY_REG, AD7150_CH2_TIMEOUT_REG }, +}; + +static int ad7150_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, + int *val2, + long mask) +{ + struct ad7150_chip_info *chip = iio_priv(indio_dev); + int channel = chan->channel; + int ret; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + ret = i2c_smbus_read_word_swapped(chip->client, + ad7150_addresses[channel][0]); + if (ret < 0) + return ret; + *val = ret >> 4; + + return IIO_VAL_INT; + case IIO_CHAN_INFO_AVERAGE_RAW: + ret = i2c_smbus_read_word_swapped(chip->client, + ad7150_addresses[channel][1]); + if (ret < 0) + return ret; + *val = ret; + + return IIO_VAL_INT; + case IIO_CHAN_INFO_SCALE: + /* + * Base units for capacitance are nano farads and the value + * calculated from the datasheet formula is in picofarad + * so multiply by 1000 + */ + *val = 1000; + *val2 = 40944 >> 4; /* To match shift in _RAW */ + return IIO_VAL_FRACTIONAL; + case IIO_CHAN_INFO_OFFSET: + *val = -(12288 >> 4); /* To match shift in _RAW */ + return IIO_VAL_INT; + case IIO_CHAN_INFO_SAMP_FREQ: + /* Strangely same for both 1 and 2 chan parts */ + *val = 100; + return IIO_VAL_INT; + default: + return -EINVAL; + } +} + +static int ad7150_read_event_config(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, + enum iio_event_type type, + enum iio_event_direction dir) +{ + struct ad7150_chip_info *chip = iio_priv(indio_dev); + u8 threshtype; + bool thrfixed; + int ret; + + ret = i2c_smbus_read_byte_data(chip->client, AD7150_CFG_REG); + if (ret < 0) + return ret; + + threshtype = FIELD_GET(AD7150_CFG_THRESHTYPE_MSK, ret); + + /*check if threshold mode is fixed or adaptive*/ + thrfixed = FIELD_GET(AD7150_CFG_FIX, ret); + + switch (type) { + case IIO_EV_TYPE_THRESH_ADAPTIVE: + if (dir == IIO_EV_DIR_RISING) + return !thrfixed && (threshtype == AD7150_CFG_TT_POS); + return !thrfixed && (threshtype == AD7150_CFG_TT_NEG); + case IIO_EV_TYPE_THRESH: + if (dir == IIO_EV_DIR_RISING) + return thrfixed && (threshtype == AD7150_CFG_TT_POS); + return thrfixed && (threshtype == AD7150_CFG_TT_NEG); + default: + break; + } + return -EINVAL; +} + +/* state_lock should be held to ensure consistent state */ +static int ad7150_write_event_params(struct iio_dev *indio_dev, + unsigned int chan, + enum iio_event_type type, + enum iio_event_direction dir) +{ + struct ad7150_chip_info *chip = iio_priv(indio_dev); + int rising = (dir == IIO_EV_DIR_RISING); + + /* Only update value live, if parameter is in use */ + if ((type != chip->type) || (dir != chip->dir)) + return 0; + + switch (type) { + /* Note completely different from the adaptive versions */ + case IIO_EV_TYPE_THRESH: { + u16 value = chip->threshold[rising][chan]; + return i2c_smbus_write_word_swapped(chip->client, + ad7150_addresses[chan][3], + value); + } + case IIO_EV_TYPE_THRESH_ADAPTIVE: { + int ret; + u8 sens, timeout; + + sens = chip->thresh_sensitivity[rising][chan]; + ret = i2c_smbus_write_byte_data(chip->client, + ad7150_addresses[chan][4], + sens); + if (ret) + return ret; + + /* + * Single timeout register contains timeouts for both + * directions. + */ + timeout = FIELD_PREP(AD7150_CH_TIMEOUT_APPROACHING, + chip->thresh_timeout[1][chan]); + timeout |= FIELD_PREP(AD7150_CH_TIMEOUT_RECEDING, + chip->thresh_timeout[0][chan]); + return i2c_smbus_write_byte_data(chip->client, + ad7150_addresses[chan][5], + timeout); + } + default: + return -EINVAL; + } +} + +static int ad7150_write_event_config(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, + enum iio_event_type type, + enum iio_event_direction dir, int state) +{ + struct ad7150_chip_info *chip = iio_priv(indio_dev); + int ret = 0; + + /* + * There is only a single shared control and no on chip + * interrupt disables for the two interrupt lines. + * So, enabling will switch the events configured to enable + * whatever was most recently requested and if necessary enable_irq() + * the interrupt and any disable will disable_irq() for that + * channels interrupt. + */ + if (!state) { + if ((chip->int_enabled[chan->channel]) && + (type == chip->type) && (dir == chip->dir)) { + disable_irq(chip->interrupts[chan->channel]); + chip->int_enabled[chan->channel] = false; + } + return 0; + } + + mutex_lock(&chip->state_lock); + if ((type != chip->type) || (dir != chip->dir)) { + int rising = (dir == IIO_EV_DIR_RISING); + u8 thresh_type, cfg, fixed; + + /* + * Need to temporarily disable both interrupts if + * enabled - this is to avoid races around changing + * config and thresholds. + * Note enable/disable_irq() are reference counted so + * no need to check if already enabled. + */ + disable_irq(chip->interrupts[0]); + disable_irq(chip->interrupts[1]); + + ret = i2c_smbus_read_byte_data(chip->client, AD7150_CFG_REG); + if (ret < 0) + goto error_ret; + + cfg = ret & ~(AD7150_CFG_THRESHTYPE_MSK | AD7150_CFG_FIX); + + if (type == IIO_EV_TYPE_THRESH_ADAPTIVE) + fixed = 0; + else + fixed = 1; + + if (rising) + thresh_type = AD7150_CFG_TT_POS; + else + thresh_type = AD7150_CFG_TT_NEG; + + cfg |= FIELD_PREP(AD7150_CFG_FIX, fixed) | + FIELD_PREP(AD7150_CFG_THRESHTYPE_MSK, thresh_type); + + ret = i2c_smbus_write_byte_data(chip->client, AD7150_CFG_REG, + cfg); + if (ret < 0) + goto error_ret; + + /* + * There is a potential race condition here, but not easy + * to close given we can't disable the interrupt at the + * chip side of things. Rely on the status bit. + */ + chip->type = type; + chip->dir = dir; + + /* update control attributes */ + ret = ad7150_write_event_params(indio_dev, chan->channel, type, + dir); + if (ret) + goto error_ret; + /* reenable any irq's we disabled whilst changing mode */ + enable_irq(chip->interrupts[0]); + enable_irq(chip->interrupts[1]); + } + if (!chip->int_enabled[chan->channel]) { + enable_irq(chip->interrupts[chan->channel]); + chip->int_enabled[chan->channel] = true; + } + +error_ret: + mutex_unlock(&chip->state_lock); + + return ret; +} + +static int ad7150_read_event_value(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, + enum iio_event_type type, + enum iio_event_direction dir, + enum iio_event_info info, + int *val, int *val2) +{ + struct ad7150_chip_info *chip = iio_priv(indio_dev); + int rising = (dir == IIO_EV_DIR_RISING); + + /* Complex register sharing going on here */ + switch (info) { + case IIO_EV_INFO_VALUE: + switch (type) { + case IIO_EV_TYPE_THRESH_ADAPTIVE: + *val = chip->thresh_sensitivity[rising][chan->channel]; + return IIO_VAL_INT; + case IIO_EV_TYPE_THRESH: + *val = chip->threshold[rising][chan->channel]; + return IIO_VAL_INT; + default: + return -EINVAL; + } + case IIO_EV_INFO_TIMEOUT: + *val = 0; + *val2 = chip->thresh_timeout[rising][chan->channel] * 10000; + return IIO_VAL_INT_PLUS_MICRO; + default: + return -EINVAL; + } +} + +static int ad7150_write_event_value(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, + enum iio_event_type type, + enum iio_event_direction dir, + enum iio_event_info info, + int val, int val2) +{ + int ret; + struct ad7150_chip_info *chip = iio_priv(indio_dev); + int rising = (dir == IIO_EV_DIR_RISING); + + mutex_lock(&chip->state_lock); + switch (info) { + case IIO_EV_INFO_VALUE: + switch (type) { + case IIO_EV_TYPE_THRESH_ADAPTIVE: + chip->thresh_sensitivity[rising][chan->channel] = val; + break; + case IIO_EV_TYPE_THRESH: + chip->threshold[rising][chan->channel] = val; + break; + default: + ret = -EINVAL; + goto error_ret; + } + break; + case IIO_EV_INFO_TIMEOUT: { + /* + * Raw timeout is in cycles of 10 msecs as long as both + * channels are enabled. + * In terms of INT_PLUS_MICRO, that is in units of 10,000 + */ + int timeout = val2 / 10000; + + if (val != 0 || timeout < 0 || timeout > 15 || val2 % 10000) { + ret = -EINVAL; + goto error_ret; + } + + chip->thresh_timeout[rising][chan->channel] = timeout; + break; + } + default: + ret = -EINVAL; + goto error_ret; + } + + /* write back if active */ + ret = ad7150_write_event_params(indio_dev, chan->channel, type, dir); + +error_ret: + mutex_unlock(&chip->state_lock); + return ret; +} + +static const struct iio_event_spec ad7150_events[] = { + { + .type = IIO_EV_TYPE_THRESH, + .dir = IIO_EV_DIR_RISING, + .mask_separate = BIT(IIO_EV_INFO_VALUE) | + BIT(IIO_EV_INFO_ENABLE), + }, { + .type = IIO_EV_TYPE_THRESH, + .dir = IIO_EV_DIR_FALLING, + .mask_separate = BIT(IIO_EV_INFO_VALUE) | + BIT(IIO_EV_INFO_ENABLE), + }, { + .type = IIO_EV_TYPE_THRESH_ADAPTIVE, + .dir = IIO_EV_DIR_RISING, + .mask_separate = BIT(IIO_EV_INFO_VALUE) | + BIT(IIO_EV_INFO_ENABLE) | + BIT(IIO_EV_INFO_TIMEOUT), + }, { + .type = IIO_EV_TYPE_THRESH_ADAPTIVE, + .dir = IIO_EV_DIR_FALLING, + .mask_separate = BIT(IIO_EV_INFO_VALUE) | + BIT(IIO_EV_INFO_ENABLE) | + BIT(IIO_EV_INFO_TIMEOUT), + }, +}; + +#define AD7150_CAPACITANCE_CHAN(_chan) { \ + .type = IIO_CAPACITANCE, \ + .indexed = 1, \ + .channel = _chan, \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ + BIT(IIO_CHAN_INFO_AVERAGE_RAW), \ + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \ + BIT(IIO_CHAN_INFO_OFFSET), \ + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),\ + .event_spec = ad7150_events, \ + .num_event_specs = ARRAY_SIZE(ad7150_events), \ + } + +#define AD7150_CAPACITANCE_CHAN_NO_IRQ(_chan) { \ + .type = IIO_CAPACITANCE, \ + .indexed = 1, \ + .channel = _chan, \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ + BIT(IIO_CHAN_INFO_AVERAGE_RAW), \ + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \ + BIT(IIO_CHAN_INFO_OFFSET), \ + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),\ + } + +static const struct iio_chan_spec ad7150_channels[] = { + AD7150_CAPACITANCE_CHAN(0), + AD7150_CAPACITANCE_CHAN(1), +}; + +static const struct iio_chan_spec ad7150_channels_no_irq[] = { + AD7150_CAPACITANCE_CHAN_NO_IRQ(0), + AD7150_CAPACITANCE_CHAN_NO_IRQ(1), +}; + +static const struct iio_chan_spec ad7151_channels[] = { + AD7150_CAPACITANCE_CHAN(0), +}; + +static const struct iio_chan_spec ad7151_channels_no_irq[] = { + AD7150_CAPACITANCE_CHAN_NO_IRQ(0), +}; + +static irqreturn_t __ad7150_event_handler(void *private, u8 status_mask, + int channel) +{ + struct iio_dev *indio_dev = private; + struct ad7150_chip_info *chip = iio_priv(indio_dev); + s64 timestamp = iio_get_time_ns(indio_dev); + int int_status; + + int_status = i2c_smbus_read_byte_data(chip->client, AD7150_STATUS_REG); + if (int_status < 0) + return IRQ_HANDLED; + + if (!(int_status & status_mask)) + return IRQ_HANDLED; + + iio_push_event(indio_dev, + IIO_UNMOD_EVENT_CODE(IIO_CAPACITANCE, channel, + chip->type, chip->dir), + timestamp); + + return IRQ_HANDLED; +} + +static irqreturn_t ad7150_event_handler_ch1(int irq, void *private) +{ + return __ad7150_event_handler(private, AD7150_STATUS_OUT1, 0); +} + +static irqreturn_t ad7150_event_handler_ch2(int irq, void *private) +{ + return __ad7150_event_handler(private, AD7150_STATUS_OUT2, 1); +} + +static IIO_CONST_ATTR(in_capacitance_thresh_adaptive_timeout_available, + "[0 0.01 0.15]"); + +static struct attribute *ad7150_event_attributes[] = { + &iio_const_attr_in_capacitance_thresh_adaptive_timeout_available + .dev_attr.attr, + NULL, +}; + +static const struct attribute_group ad7150_event_attribute_group = { + .attrs = ad7150_event_attributes, + .name = "events", +}; + +static const struct iio_info ad7150_info = { + .event_attrs = &ad7150_event_attribute_group, + .read_raw = &ad7150_read_raw, + .read_event_config = &ad7150_read_event_config, + .write_event_config = &ad7150_write_event_config, + .read_event_value = &ad7150_read_event_value, + .write_event_value = &ad7150_write_event_value, +}; + +static const struct iio_info ad7150_info_no_irq = { + .read_raw = &ad7150_read_raw, +}; + +static int ad7150_probe(struct i2c_client *client) +{ + const struct i2c_device_id *id = i2c_client_get_device_id(client); + struct ad7150_chip_info *chip; + struct iio_dev *indio_dev; + bool use_irq = true; + int ret; + + indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*chip)); + if (!indio_dev) + return -ENOMEM; + + chip = iio_priv(indio_dev); + mutex_init(&chip->state_lock); + chip->client = client; + + indio_dev->name = id->name; + + indio_dev->modes = INDIO_DIRECT_MODE; + + ret = devm_regulator_get_enable(&client->dev, "vdd"); + if (ret) + return ret; + + chip->interrupts[0] = fwnode_irq_get(dev_fwnode(&client->dev), 0); + if (chip->interrupts[0] < 0) + use_irq = false; + else if (id->driver_data == AD7150) { + chip->interrupts[1] = fwnode_irq_get(dev_fwnode(&client->dev), 1); + if (chip->interrupts[1] < 0) + use_irq = false; + } + if (use_irq) { + irq_set_status_flags(chip->interrupts[0], IRQ_NOAUTOEN); + ret = devm_request_threaded_irq(&client->dev, + chip->interrupts[0], + NULL, + &ad7150_event_handler_ch1, + IRQF_TRIGGER_RISING | + IRQF_ONESHOT, + "ad7150_irq1", + indio_dev); + if (ret) + return ret; + + indio_dev->info = &ad7150_info; + switch (id->driver_data) { + case AD7150: + indio_dev->channels = ad7150_channels; + indio_dev->num_channels = ARRAY_SIZE(ad7150_channels); + irq_set_status_flags(chip->interrupts[1], IRQ_NOAUTOEN); + ret = devm_request_threaded_irq(&client->dev, + chip->interrupts[1], + NULL, + &ad7150_event_handler_ch2, + IRQF_TRIGGER_RISING | + IRQF_ONESHOT, + "ad7150_irq2", + indio_dev); + if (ret) + return ret; + break; + case AD7151: + indio_dev->channels = ad7151_channels; + indio_dev->num_channels = ARRAY_SIZE(ad7151_channels); + break; + default: + return -EINVAL; + } + + } else { + indio_dev->info = &ad7150_info_no_irq; + switch (id->driver_data) { + case AD7150: + indio_dev->channels = ad7150_channels_no_irq; + indio_dev->num_channels = + ARRAY_SIZE(ad7150_channels_no_irq); + break; + case AD7151: + indio_dev->channels = ad7151_channels_no_irq; + indio_dev->num_channels = + ARRAY_SIZE(ad7151_channels_no_irq); + break; + default: + return -EINVAL; + } + } + + return devm_iio_device_register(indio_dev->dev.parent, indio_dev); +} + +static const struct i2c_device_id ad7150_id[] = { + { "ad7150", AD7150 }, + { "ad7151", AD7151 }, + { "ad7156", AD7150 }, + {} +}; + +MODULE_DEVICE_TABLE(i2c, ad7150_id); + +static const struct of_device_id ad7150_of_match[] = { + { "adi,ad7150" }, + { "adi,ad7151" }, + { "adi,ad7156" }, + {} +}; +static struct i2c_driver ad7150_driver = { + .driver = { + .name = "ad7150", + .of_match_table = ad7150_of_match, + }, + .probe = ad7150_probe, + .id_table = ad7150_id, +}; +module_i2c_driver(ad7150_driver); + +MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>"); +MODULE_DESCRIPTION("Analog Devices AD7150/1/6 capacitive sensor driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/iio/cdc/ad7746.c b/drivers/iio/cdc/ad7746.c new file mode 100644 index 0000000000..d11bc3496d --- /dev/null +++ b/drivers/iio/cdc/ad7746.c @@ -0,0 +1,819 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * AD7746 capacitive sensor driver supporting AD7745, AD7746 and AD7747 + * + * Copyright 2011 Analog Devices Inc. + */ + +#include <linux/bitfield.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/stat.h> +#include <linux/sysfs.h> + +#include <asm/unaligned.h> + +#include <linux/iio/iio.h> +#include <linux/iio/sysfs.h> + +/* AD7746 Register Definition */ + +#define AD7746_REG_STATUS 0 +#define AD7746_REG_CAP_DATA_HIGH 1 +#define AD7746_REG_VT_DATA_HIGH 4 +#define AD7746_REG_CAP_SETUP 7 +#define AD7746_REG_VT_SETUP 8 +#define AD7746_REG_EXC_SETUP 9 +#define AD7746_REG_CFG 10 +#define AD7746_REG_CAPDACA 11 +#define AD7746_REG_CAPDACB 12 +#define AD7746_REG_CAP_OFFH 13 +#define AD7746_REG_CAP_GAINH 15 +#define AD7746_REG_VOLT_GAINH 17 + +/* Status Register Bit Designations (AD7746_REG_STATUS) */ +#define AD7746_STATUS_EXCERR BIT(3) +#define AD7746_STATUS_RDY BIT(2) +#define AD7746_STATUS_RDYVT BIT(1) +#define AD7746_STATUS_RDYCAP BIT(0) + +/* Capacitive Channel Setup Register Bit Designations (AD7746_REG_CAP_SETUP) */ +#define AD7746_CAPSETUP_CAPEN BIT(7) +#define AD7746_CAPSETUP_CIN2 BIT(6) /* AD7746 only */ +#define AD7746_CAPSETUP_CAPDIFF BIT(5) +#define AD7746_CAPSETUP_CACHOP BIT(0) + +/* Voltage/Temperature Setup Register Bit Designations (AD7746_REG_VT_SETUP) */ +#define AD7746_VTSETUP_VTEN BIT(7) +#define AD7746_VTSETUP_VTMD_MASK GENMASK(6, 5) +#define AD7746_VTSETUP_VTMD_INT_TEMP 0 +#define AD7746_VTSETUP_VTMD_EXT_TEMP 1 +#define AD7746_VTSETUP_VTMD_VDD_MON 2 +#define AD7746_VTSETUP_VTMD_EXT_VIN 3 +#define AD7746_VTSETUP_EXTREF BIT(4) +#define AD7746_VTSETUP_VTSHORT BIT(1) +#define AD7746_VTSETUP_VTCHOP BIT(0) + +/* Excitation Setup Register Bit Designations (AD7746_REG_EXC_SETUP) */ +#define AD7746_EXCSETUP_CLKCTRL BIT(7) +#define AD7746_EXCSETUP_EXCON BIT(6) +#define AD7746_EXCSETUP_EXCB BIT(5) +#define AD7746_EXCSETUP_NEXCB BIT(4) +#define AD7746_EXCSETUP_EXCA BIT(3) +#define AD7746_EXCSETUP_NEXCA BIT(2) +#define AD7746_EXCSETUP_EXCLVL_MASK GENMASK(1, 0) + +/* Config Register Bit Designations (AD7746_REG_CFG) */ +#define AD7746_CONF_VTFS_MASK GENMASK(7, 6) +#define AD7746_CONF_CAPFS_MASK GENMASK(5, 3) +#define AD7746_CONF_MODE_MASK GENMASK(2, 0) +#define AD7746_CONF_MODE_IDLE 0 +#define AD7746_CONF_MODE_CONT_CONV 1 +#define AD7746_CONF_MODE_SINGLE_CONV 2 +#define AD7746_CONF_MODE_PWRDN 3 +#define AD7746_CONF_MODE_OFFS_CAL 5 +#define AD7746_CONF_MODE_GAIN_CAL 6 + +/* CAPDAC Register Bit Designations (AD7746_REG_CAPDACx) */ +#define AD7746_CAPDAC_DACEN BIT(7) +#define AD7746_CAPDAC_DACP_MASK GENMASK(6, 0) + +struct ad7746_chip_info { + struct i2c_client *client; + struct mutex lock; /* protect sensor state */ + /* + * Capacitive channel digital filter setup; + * conversion time/update rate setup per channel + */ + u8 config; + u8 cap_setup; + u8 vt_setup; + u8 capdac[2][2]; + s8 capdac_set; +}; + +enum ad7746_chan { + VIN, + VIN_VDD, + TEMP_INT, + TEMP_EXT, + CIN1, + CIN1_DIFF, + CIN2, + CIN2_DIFF, +}; + +struct ad7746_chan_info { + u8 addr; + union { + u8 vtmd; + struct { /* CAP SETUP fields */ + unsigned int cin2 : 1; + unsigned int capdiff : 1; + }; + }; +}; + +static const struct ad7746_chan_info ad7746_chan_info[] = { + [VIN] = { + .addr = AD7746_REG_VT_DATA_HIGH, + .vtmd = AD7746_VTSETUP_VTMD_EXT_VIN, + }, + [VIN_VDD] = { + .addr = AD7746_REG_VT_DATA_HIGH, + .vtmd = AD7746_VTSETUP_VTMD_VDD_MON, + }, + [TEMP_INT] = { + .addr = AD7746_REG_VT_DATA_HIGH, + .vtmd = AD7746_VTSETUP_VTMD_INT_TEMP, + }, + [TEMP_EXT] = { + .addr = AD7746_REG_VT_DATA_HIGH, + .vtmd = AD7746_VTSETUP_VTMD_EXT_TEMP, + }, + [CIN1] = { + .addr = AD7746_REG_CAP_DATA_HIGH, + }, + [CIN1_DIFF] = { + .addr = AD7746_REG_CAP_DATA_HIGH, + .capdiff = 1, + }, + [CIN2] = { + .addr = AD7746_REG_CAP_DATA_HIGH, + .cin2 = 1, + }, + [CIN2_DIFF] = { + .addr = AD7746_REG_CAP_DATA_HIGH, + .cin2 = 1, + .capdiff = 1, + }, +}; + +static const struct iio_chan_spec ad7746_channels[] = { + [VIN] = { + .type = IIO_VOLTAGE, + .indexed = 1, + .channel = 0, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE), + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ), + .info_mask_shared_by_type_available = BIT(IIO_CHAN_INFO_SAMP_FREQ), + .address = VIN, + }, + [VIN_VDD] = { + .type = IIO_VOLTAGE, + .indexed = 1, + .channel = 1, + .extend_name = "supply", + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE), + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ), + .info_mask_shared_by_type_available = BIT(IIO_CHAN_INFO_SAMP_FREQ), + .address = VIN_VDD, + }, + [TEMP_INT] = { + .type = IIO_TEMP, + .indexed = 1, + .channel = 0, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), + .address = TEMP_INT, + }, + [TEMP_EXT] = { + .type = IIO_TEMP, + .indexed = 1, + .channel = 1, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), + .address = TEMP_EXT, + }, + [CIN1] = { + .type = IIO_CAPACITANCE, + .indexed = 1, + .channel = 0, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | + BIT(IIO_CHAN_INFO_CALIBSCALE) | BIT(IIO_CHAN_INFO_OFFSET), + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_CALIBBIAS) | + BIT(IIO_CHAN_INFO_SCALE) | BIT(IIO_CHAN_INFO_SAMP_FREQ), + .info_mask_shared_by_type_available = BIT(IIO_CHAN_INFO_SAMP_FREQ), + .address = CIN1, + }, + [CIN1_DIFF] = { + .type = IIO_CAPACITANCE, + .differential = 1, + .indexed = 1, + .channel = 0, + .channel2 = 2, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | + BIT(IIO_CHAN_INFO_CALIBSCALE) | BIT(IIO_CHAN_INFO_ZEROPOINT), + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_CALIBBIAS) | + BIT(IIO_CHAN_INFO_SCALE) | BIT(IIO_CHAN_INFO_SAMP_FREQ), + .info_mask_shared_by_type_available = BIT(IIO_CHAN_INFO_SAMP_FREQ), + .address = CIN1_DIFF, + }, + [CIN2] = { + .type = IIO_CAPACITANCE, + .indexed = 1, + .channel = 1, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | + BIT(IIO_CHAN_INFO_CALIBSCALE) | BIT(IIO_CHAN_INFO_OFFSET), + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_CALIBBIAS) | + BIT(IIO_CHAN_INFO_SCALE) | BIT(IIO_CHAN_INFO_SAMP_FREQ), + .info_mask_shared_by_type_available = BIT(IIO_CHAN_INFO_SAMP_FREQ), + .address = CIN2, + }, + [CIN2_DIFF] = { + .type = IIO_CAPACITANCE, + .differential = 1, + .indexed = 1, + .channel = 1, + .channel2 = 3, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | + BIT(IIO_CHAN_INFO_CALIBSCALE) | BIT(IIO_CHAN_INFO_ZEROPOINT), + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_CALIBBIAS) | + BIT(IIO_CHAN_INFO_SCALE) | BIT(IIO_CHAN_INFO_SAMP_FREQ), + .info_mask_shared_by_type_available = BIT(IIO_CHAN_INFO_SAMP_FREQ), + .address = CIN2_DIFF, + } +}; + +/* Values are Update Rate (Hz), Conversion Time (ms) + 1*/ +static const unsigned char ad7746_vt_filter_rate_table[][2] = { + { 50, 20 + 1 }, { 31, 32 + 1 }, { 16, 62 + 1 }, { 8, 122 + 1 }, +}; + +static const unsigned char ad7746_cap_filter_rate_table[][2] = { + { 91, 11 + 1 }, { 84, 12 + 1 }, { 50, 20 + 1 }, { 26, 38 + 1 }, + { 16, 62 + 1 }, { 13, 77 + 1 }, { 11, 92 + 1 }, { 9, 110 + 1 }, +}; + +static int ad7746_set_capdac(struct ad7746_chip_info *chip, int channel) +{ + int ret = i2c_smbus_write_byte_data(chip->client, + AD7746_REG_CAPDACA, + chip->capdac[channel][0]); + if (ret < 0) + return ret; + + return i2c_smbus_write_byte_data(chip->client, + AD7746_REG_CAPDACB, + chip->capdac[channel][1]); +} + +static int ad7746_select_channel(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan) +{ + struct ad7746_chip_info *chip = iio_priv(indio_dev); + u8 vt_setup, cap_setup; + int ret, delay, idx; + + switch (chan->type) { + case IIO_CAPACITANCE: + cap_setup = FIELD_PREP(AD7746_CAPSETUP_CIN2, + ad7746_chan_info[chan->address].cin2) | + FIELD_PREP(AD7746_CAPSETUP_CAPDIFF, + ad7746_chan_info[chan->address].capdiff) | + FIELD_PREP(AD7746_CAPSETUP_CAPEN, 1); + vt_setup = chip->vt_setup & ~AD7746_VTSETUP_VTEN; + idx = FIELD_GET(AD7746_CONF_CAPFS_MASK, chip->config); + delay = ad7746_cap_filter_rate_table[idx][1]; + + ret = ad7746_set_capdac(chip, chan->channel); + if (ret < 0) + return ret; + + chip->capdac_set = chan->channel; + break; + case IIO_VOLTAGE: + case IIO_TEMP: + vt_setup = FIELD_PREP(AD7746_VTSETUP_VTMD_MASK, + ad7746_chan_info[chan->address].vtmd) | + FIELD_PREP(AD7746_VTSETUP_VTEN, 1); + cap_setup = chip->cap_setup & ~AD7746_CAPSETUP_CAPEN; + idx = FIELD_GET(AD7746_CONF_VTFS_MASK, chip->config); + delay = ad7746_cap_filter_rate_table[idx][1]; + break; + default: + return -EINVAL; + } + + if (chip->cap_setup != cap_setup) { + ret = i2c_smbus_write_byte_data(chip->client, + AD7746_REG_CAP_SETUP, + cap_setup); + if (ret < 0) + return ret; + + chip->cap_setup = cap_setup; + } + + if (chip->vt_setup != vt_setup) { + ret = i2c_smbus_write_byte_data(chip->client, + AD7746_REG_VT_SETUP, + vt_setup); + if (ret < 0) + return ret; + + chip->vt_setup = vt_setup; + } + + return delay; +} + +static inline ssize_t ad7746_start_calib(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t len, + u8 regval) +{ + struct iio_dev *indio_dev = dev_to_iio_dev(dev); + struct ad7746_chip_info *chip = iio_priv(indio_dev); + int ret, timeout = 10; + bool doit; + + ret = kstrtobool(buf, &doit); + if (ret < 0) + return ret; + + if (!doit) + return 0; + + mutex_lock(&chip->lock); + regval |= chip->config; + ret = i2c_smbus_write_byte_data(chip->client, AD7746_REG_CFG, regval); + if (ret < 0) + goto unlock; + + do { + msleep(20); + ret = i2c_smbus_read_byte_data(chip->client, AD7746_REG_CFG); + if (ret < 0) + goto unlock; + + } while ((ret == regval) && timeout--); + + mutex_unlock(&chip->lock); + + return len; + +unlock: + mutex_unlock(&chip->lock); + return ret; +} + +static ssize_t ad7746_start_offset_calib(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t len) +{ + struct iio_dev *indio_dev = dev_to_iio_dev(dev); + int ret = ad7746_select_channel(indio_dev, + &ad7746_channels[to_iio_dev_attr(attr)->address]); + if (ret < 0) + return ret; + + return ad7746_start_calib(dev, attr, buf, len, + FIELD_PREP(AD7746_CONF_MODE_MASK, + AD7746_CONF_MODE_OFFS_CAL)); +} + +static ssize_t ad7746_start_gain_calib(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t len) +{ + struct iio_dev *indio_dev = dev_to_iio_dev(dev); + int ret = ad7746_select_channel(indio_dev, + &ad7746_channels[to_iio_dev_attr(attr)->address]); + if (ret < 0) + return ret; + + return ad7746_start_calib(dev, attr, buf, len, + FIELD_PREP(AD7746_CONF_MODE_MASK, + AD7746_CONF_MODE_GAIN_CAL)); +} + +static IIO_DEVICE_ATTR(in_capacitance0_calibbias_calibration, + 0200, NULL, ad7746_start_offset_calib, CIN1); +static IIO_DEVICE_ATTR(in_capacitance1_calibbias_calibration, + 0200, NULL, ad7746_start_offset_calib, CIN2); +static IIO_DEVICE_ATTR(in_capacitance0_calibscale_calibration, + 0200, NULL, ad7746_start_gain_calib, CIN1); +static IIO_DEVICE_ATTR(in_capacitance1_calibscale_calibration, + 0200, NULL, ad7746_start_gain_calib, CIN2); +static IIO_DEVICE_ATTR(in_voltage0_calibscale_calibration, + 0200, NULL, ad7746_start_gain_calib, VIN); + +static int ad7746_store_cap_filter_rate_setup(struct ad7746_chip_info *chip, + int val) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(ad7746_cap_filter_rate_table); i++) + if (val >= ad7746_cap_filter_rate_table[i][0]) + break; + + if (i >= ARRAY_SIZE(ad7746_cap_filter_rate_table)) + i = ARRAY_SIZE(ad7746_cap_filter_rate_table) - 1; + + chip->config &= ~AD7746_CONF_CAPFS_MASK; + chip->config |= FIELD_PREP(AD7746_CONF_CAPFS_MASK, i); + + return 0; +} + +static int ad7746_store_vt_filter_rate_setup(struct ad7746_chip_info *chip, + int val) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(ad7746_vt_filter_rate_table); i++) + if (val >= ad7746_vt_filter_rate_table[i][0]) + break; + + if (i >= ARRAY_SIZE(ad7746_vt_filter_rate_table)) + i = ARRAY_SIZE(ad7746_vt_filter_rate_table) - 1; + + chip->config &= ~AD7746_CONF_VTFS_MASK; + chip->config |= FIELD_PREP(AD7746_CONF_VTFS_MASK, i); + + return 0; +} + +static struct attribute *ad7746_attributes[] = { + &iio_dev_attr_in_capacitance0_calibbias_calibration.dev_attr.attr, + &iio_dev_attr_in_capacitance0_calibscale_calibration.dev_attr.attr, + &iio_dev_attr_in_capacitance1_calibscale_calibration.dev_attr.attr, + &iio_dev_attr_in_capacitance1_calibbias_calibration.dev_attr.attr, + &iio_dev_attr_in_voltage0_calibscale_calibration.dev_attr.attr, + NULL, +}; + +static const struct attribute_group ad7746_attribute_group = { + .attrs = ad7746_attributes, +}; + +static int ad7746_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, + int val2, + long mask) +{ + struct ad7746_chip_info *chip = iio_priv(indio_dev); + int ret, reg; + + switch (mask) { + case IIO_CHAN_INFO_CALIBSCALE: + if (val != 1) + return -EINVAL; + + val = (val2 * 1024) / 15625; + + switch (chan->type) { + case IIO_CAPACITANCE: + reg = AD7746_REG_CAP_GAINH; + break; + case IIO_VOLTAGE: + reg = AD7746_REG_VOLT_GAINH; + break; + default: + return -EINVAL; + } + + mutex_lock(&chip->lock); + ret = i2c_smbus_write_word_swapped(chip->client, reg, val); + mutex_unlock(&chip->lock); + if (ret < 0) + return ret; + + return 0; + case IIO_CHAN_INFO_CALIBBIAS: + if (val < 0 || val > 0xFFFF) + return -EINVAL; + + mutex_lock(&chip->lock); + ret = i2c_smbus_write_word_swapped(chip->client, + AD7746_REG_CAP_OFFH, val); + mutex_unlock(&chip->lock); + if (ret < 0) + return ret; + + return 0; + case IIO_CHAN_INFO_OFFSET: + case IIO_CHAN_INFO_ZEROPOINT: + if (val < 0 || val > 43008000) /* 21pF */ + return -EINVAL; + + /* + * CAPDAC Scale = 21pF_typ / 127 + * CIN Scale = 8.192pF / 2^24 + * Offset Scale = CAPDAC Scale / CIN Scale = 338646 + */ + + val /= 338646; + mutex_lock(&chip->lock); + chip->capdac[chan->channel][chan->differential] = val > 0 ? + FIELD_PREP(AD7746_CAPDAC_DACP_MASK, val) | AD7746_CAPDAC_DACEN : 0; + + ret = ad7746_set_capdac(chip, chan->channel); + if (ret < 0) { + mutex_unlock(&chip->lock); + return ret; + } + + chip->capdac_set = chan->channel; + mutex_unlock(&chip->lock); + + return 0; + case IIO_CHAN_INFO_SAMP_FREQ: + if (val2) + return -EINVAL; + + switch (chan->type) { + case IIO_CAPACITANCE: + mutex_lock(&chip->lock); + ret = ad7746_store_cap_filter_rate_setup(chip, val); + mutex_unlock(&chip->lock); + return ret; + case IIO_VOLTAGE: + mutex_lock(&chip->lock); + ret = ad7746_store_vt_filter_rate_setup(chip, val); + mutex_unlock(&chip->lock); + return ret; + default: + return -EINVAL; + } + default: + return -EINVAL; + } +} + +static const int ad7746_v_samp_freq[] = { 50, 31, 16, 8, }; +static const int ad7746_cap_samp_freq[] = { 91, 84, 50, 26, 16, 13, 11, 9, }; + +static int ad7746_read_avail(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, const int **vals, + int *type, int *length, long mask) +{ + if (mask != IIO_CHAN_INFO_SAMP_FREQ) + return -EINVAL; + + switch (chan->type) { + case IIO_VOLTAGE: + *vals = ad7746_v_samp_freq; + *length = ARRAY_SIZE(ad7746_v_samp_freq); + break; + case IIO_CAPACITANCE: + *vals = ad7746_cap_samp_freq; + *length = ARRAY_SIZE(ad7746_cap_samp_freq); + break; + default: + return -EINVAL; + } + *type = IIO_VAL_INT; + return IIO_AVAIL_LIST; +} + +static int ad7746_read_channel(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val) +{ + struct ad7746_chip_info *chip = iio_priv(indio_dev); + int ret, delay; + u8 data[3]; + u8 regval; + + ret = ad7746_select_channel(indio_dev, chan); + if (ret < 0) + return ret; + delay = ret; + + regval = chip->config | FIELD_PREP(AD7746_CONF_MODE_MASK, + AD7746_CONF_MODE_SINGLE_CONV); + ret = i2c_smbus_write_byte_data(chip->client, AD7746_REG_CFG, regval); + if (ret < 0) + return ret; + + msleep(delay); + /* Now read the actual register */ + ret = i2c_smbus_read_i2c_block_data(chip->client, + ad7746_chan_info[chan->address].addr, + sizeof(data), data); + if (ret < 0) + return ret; + + /* + * Offset applied internally becaue the _offset userspace interface is + * needed for the CAP DACs which apply a controllable offset. + */ + *val = get_unaligned_be24(data) - 0x800000; + + return 0; +} + +static int ad7746_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, int *val2, + long mask) +{ + struct ad7746_chip_info *chip = iio_priv(indio_dev); + int ret, idx; + u8 reg; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + mutex_lock(&chip->lock); + ret = ad7746_read_channel(indio_dev, chan, val); + mutex_unlock(&chip->lock); + if (ret < 0) + return ret; + + return IIO_VAL_INT; + case IIO_CHAN_INFO_CALIBSCALE: + switch (chan->type) { + case IIO_CAPACITANCE: + reg = AD7746_REG_CAP_GAINH; + break; + case IIO_VOLTAGE: + reg = AD7746_REG_VOLT_GAINH; + break; + default: + return -EINVAL; + } + + mutex_lock(&chip->lock); + ret = i2c_smbus_read_word_swapped(chip->client, reg); + mutex_unlock(&chip->lock); + if (ret < 0) + return ret; + /* 1 + gain_val / 2^16 */ + *val = 1; + *val2 = (15625 * ret) / 1024; + + return IIO_VAL_INT_PLUS_MICRO; + case IIO_CHAN_INFO_CALIBBIAS: + mutex_lock(&chip->lock); + ret = i2c_smbus_read_word_swapped(chip->client, + AD7746_REG_CAP_OFFH); + mutex_unlock(&chip->lock); + if (ret < 0) + return ret; + *val = ret; + + return IIO_VAL_INT; + case IIO_CHAN_INFO_OFFSET: + case IIO_CHAN_INFO_ZEROPOINT: + *val = FIELD_GET(AD7746_CAPDAC_DACP_MASK, + chip->capdac[chan->channel][chan->differential]) * 338646; + + return IIO_VAL_INT; + case IIO_CHAN_INFO_SCALE: + switch (chan->type) { + case IIO_CAPACITANCE: + /* 8.192pf / 2^24 */ + *val = 0; + *val2 = 488; + return IIO_VAL_INT_PLUS_NANO; + case IIO_VOLTAGE: + /* 1170mV / 2^23 */ + *val = 1170; + if (chan->channel == 1) + *val *= 6; + *val2 = 23; + return IIO_VAL_FRACTIONAL_LOG2; + case IIO_TEMP: + *val = 125; + *val2 = 8; + return IIO_VAL_FRACTIONAL_LOG2; + default: + return -EINVAL; + } + case IIO_CHAN_INFO_SAMP_FREQ: + switch (chan->type) { + case IIO_CAPACITANCE: + idx = FIELD_GET(AD7746_CONF_CAPFS_MASK, chip->config); + *val = ad7746_cap_filter_rate_table[idx][0]; + return IIO_VAL_INT; + case IIO_VOLTAGE: + idx = FIELD_GET(AD7746_CONF_VTFS_MASK, chip->config); + *val = ad7746_vt_filter_rate_table[idx][0]; + return IIO_VAL_INT; + default: + return -EINVAL; + } + default: + return -EINVAL; + } +} + +static const struct iio_info ad7746_info = { + .attrs = &ad7746_attribute_group, + .read_raw = ad7746_read_raw, + .read_avail = ad7746_read_avail, + .write_raw = ad7746_write_raw, +}; + +static int ad7746_probe(struct i2c_client *client) +{ + const struct i2c_device_id *id = i2c_client_get_device_id(client); + struct device *dev = &client->dev; + struct ad7746_chip_info *chip; + struct iio_dev *indio_dev; + unsigned char regval = 0; + unsigned int vdd_permille; + int ret; + + indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*chip)); + if (!indio_dev) + return -ENOMEM; + + chip = iio_priv(indio_dev); + mutex_init(&chip->lock); + + chip->client = client; + chip->capdac_set = -1; + + indio_dev->name = id->name; + indio_dev->info = &ad7746_info; + indio_dev->channels = ad7746_channels; + if (id->driver_data == 7746) + indio_dev->num_channels = ARRAY_SIZE(ad7746_channels); + else + indio_dev->num_channels = ARRAY_SIZE(ad7746_channels) - 2; + indio_dev->modes = INDIO_DIRECT_MODE; + + if (device_property_read_bool(dev, "adi,exca-output-en")) { + if (device_property_read_bool(dev, "adi,exca-output-invert")) + regval |= AD7746_EXCSETUP_NEXCA; + else + regval |= AD7746_EXCSETUP_EXCA; + } + + if (device_property_read_bool(dev, "adi,excb-output-en")) { + if (device_property_read_bool(dev, "adi,excb-output-invert")) + regval |= AD7746_EXCSETUP_NEXCB; + else + regval |= AD7746_EXCSETUP_EXCB; + } + + ret = device_property_read_u32(dev, "adi,excitation-vdd-permille", + &vdd_permille); + if (!ret) { + switch (vdd_permille) { + case 125: + regval |= FIELD_PREP(AD7746_EXCSETUP_EXCLVL_MASK, 0); + break; + case 250: + regval |= FIELD_PREP(AD7746_EXCSETUP_EXCLVL_MASK, 1); + break; + case 375: + regval |= FIELD_PREP(AD7746_EXCSETUP_EXCLVL_MASK, 2); + break; + case 500: + regval |= FIELD_PREP(AD7746_EXCSETUP_EXCLVL_MASK, 3); + break; + default: + break; + } + } + + ret = i2c_smbus_write_byte_data(chip->client, AD7746_REG_EXC_SETUP, + regval); + if (ret < 0) + return ret; + + return devm_iio_device_register(indio_dev->dev.parent, indio_dev); +} + +static const struct i2c_device_id ad7746_id[] = { + { "ad7745", 7745 }, + { "ad7746", 7746 }, + { "ad7747", 7747 }, + {} +}; +MODULE_DEVICE_TABLE(i2c, ad7746_id); + +static const struct of_device_id ad7746_of_match[] = { + { .compatible = "adi,ad7745" }, + { .compatible = "adi,ad7746" }, + { .compatible = "adi,ad7747" }, + { }, +}; +MODULE_DEVICE_TABLE(of, ad7746_of_match); + +static struct i2c_driver ad7746_driver = { + .driver = { + .name = KBUILD_MODNAME, + .of_match_table = ad7746_of_match, + }, + .probe = ad7746_probe, + .id_table = ad7746_id, +}; +module_i2c_driver(ad7746_driver); + +MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>"); +MODULE_DESCRIPTION("Analog Devices AD7746/5/7 capacitive sensor driver"); +MODULE_LICENSE("GPL v2"); |