cregit-Linux how code gets into the kernel

Release 4.11 drivers/iio/adc/ad7291.c

Directory: drivers/iio/adc
/*
 * AD7291 8-Channel, I2C, 12-Bit SAR ADC with Temperature Sensor
 *
 * Copyright 2010-2011 Analog Devices Inc.
 *
 * Licensed under the GPL-2 or later.
 */

#include <linux/device.h>
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/regulator/consumer.h>
#include <linux/slab.h>
#include <linux/sysfs.h>

#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/iio/events.h>

#include <linux/platform_data/ad7291.h>

/*
 * Simplified handling
 *
 * If no events enabled - single polled channel read
 * If event enabled direct reads disable unless channel
 * is in the read mask.
 *
 * The noise-delayed bit as per datasheet suggestion is always enabled.
 */

/*
 * AD7291 registers definition
 */

#define AD7291_COMMAND			0x00

#define AD7291_VOLTAGE			0x01

#define AD7291_T_SENSE			0x02

#define AD7291_T_AVERAGE		0x03

#define AD7291_DATA_HIGH(x)		((x) * 3 + 0x4)

#define AD7291_DATA_LOW(x)		((x) * 3 + 0x5)

#define AD7291_HYST(x)			((x) * 3 + 0x6)

#define AD7291_VOLTAGE_ALERT_STATUS	0x1F

#define AD7291_T_ALERT_STATUS		0x20


#define AD7291_BITS			12

#define AD7291_VOLTAGE_LIMIT_COUNT	8


/*
 * AD7291 command
 */

#define AD7291_AUTOCYCLE		BIT(0)

#define AD7291_RESET			BIT(1)

#define AD7291_ALERT_CLEAR		BIT(2)

#define AD7291_ALERT_POLARITY		BIT(3)

#define AD7291_EXT_REF			BIT(4)

#define AD7291_NOISE_DELAY		BIT(5)

#define AD7291_T_SENSE_MASK		BIT(7)

#define AD7291_VOLTAGE_MASK		GENMASK(15, 8)

#define AD7291_VOLTAGE_OFFSET		8

/*
 * AD7291 value masks
 */

#define AD7291_VALUE_MASK		GENMASK(11, 0)

/*
 * AD7291 alert register bits
 */

#define AD7291_T_LOW			BIT(0)

#define AD7291_T_HIGH			BIT(1)

#define AD7291_T_AVG_LOW		BIT(2)

#define AD7291_T_AVG_HIGH		BIT(3)

#define AD7291_V_LOW(x)			BIT((x) * 2)

#define AD7291_V_HIGH(x)		BIT((x) * 2 + 1)



struct ad7291_chip_info {
	
struct i2c_client	*client;
	
struct regulator	*reg;
	
u16			command;
	
u16			c_mask;	/* Active voltage channels for events */
	
struct mutex		state_lock;
};


static int ad7291_i2c_read(struct ad7291_chip_info *chip, u8 reg, u16 *data) { struct i2c_client *client = chip->client; int ret = 0; ret = i2c_smbus_read_word_swapped(client, reg); if (ret < 0) { dev_err(&client->dev, "I2C read error\n"); return ret; } *data = ret; return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Sonic Zhang6998.57%150.00%
Lars-Peter Clausen11.43%150.00%
Total70100.00%2100.00%


static int ad7291_i2c_write(struct ad7291_chip_info *chip, u8 reg, u16 data) { return i2c_smbus_write_word_swapped(chip->client, reg, data); }

Contributors

PersonTokensPropCommitsCommitProp
Sonic Zhang2586.21%133.33%
Jonathan Cameron310.34%133.33%
Lars-Peter Clausen13.45%133.33%
Total29100.00%3100.00%


static irqreturn_t ad7291_event_handler(int irq, void *private) { struct iio_dev *indio_dev = private; struct ad7291_chip_info *chip = iio_priv(private); u16 t_status, v_status; u16 command; int i; s64 timestamp = iio_get_time_ns(indio_dev); if (ad7291_i2c_read(chip, AD7291_T_ALERT_STATUS, &t_status)) return IRQ_HANDLED; if (ad7291_i2c_read(chip, AD7291_VOLTAGE_ALERT_STATUS, &v_status)) return IRQ_HANDLED; if (!(t_status || v_status)) return IRQ_HANDLED; command = chip->command | AD7291_ALERT_CLEAR; ad7291_i2c_write(chip, AD7291_COMMAND, command); command = chip->command & ~AD7291_ALERT_CLEAR; ad7291_i2c_write(chip, AD7291_COMMAND, command); /* For now treat t_sense and t_sense_average the same */ if ((t_status & AD7291_T_LOW) || (t_status & AD7291_T_AVG_LOW)) iio_push_event(indio_dev, IIO_UNMOD_EVENT_CODE(IIO_TEMP, 0, IIO_EV_TYPE_THRESH, IIO_EV_DIR_FALLING), timestamp); if ((t_status & AD7291_T_HIGH) || (t_status & AD7291_T_AVG_HIGH)) iio_push_event(indio_dev, IIO_UNMOD_EVENT_CODE(IIO_TEMP, 0, IIO_EV_TYPE_THRESH, IIO_EV_DIR_RISING), timestamp); for (i = 0; i < AD7291_VOLTAGE_LIMIT_COUNT; i++) { if (v_status & AD7291_V_LOW(i)) iio_push_event(indio_dev, IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE, i, IIO_EV_TYPE_THRESH, IIO_EV_DIR_FALLING), timestamp); if (v_status & AD7291_V_HIGH(i)) iio_push_event(indio_dev, IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE, i, IIO_EV_TYPE_THRESH, IIO_EV_DIR_RISING), timestamp); } return IRQ_HANDLED; }

Contributors

PersonTokensPropCommitsCommitProp
Jonathan Cameron18670.72%342.86%
Sonic Zhang6123.19%114.29%
Hartmut Knaack114.18%114.29%
Grégor Boirie31.14%114.29%
Michael Hennerich20.76%114.29%
Total263100.00%7100.00%


static unsigned int ad7291_threshold_reg(const struct iio_chan_spec *chan, enum iio_event_direction dir, enum iio_event_info info) { unsigned int offset; switch (chan->type) { case IIO_VOLTAGE: offset = chan->channel; break; case IIO_TEMP: offset = AD7291_VOLTAGE_OFFSET; break; default: return 0; } switch (info) { case IIO_EV_INFO_VALUE: if (dir == IIO_EV_DIR_FALLING) return AD7291_DATA_HIGH(offset); else return AD7291_DATA_LOW(offset); case IIO_EV_INFO_HYSTERESIS: return AD7291_HYST(offset); default: break; } return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Lars-Peter Clausen9193.81%360.00%
Jonathan Cameron55.15%120.00%
Hartmut Knaack11.03%120.00%
Total97100.00%5100.00%


static int ad7291_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 ad7291_chip_info *chip = iio_priv(indio_dev); int ret; u16 uval; ret = ad7291_i2c_read(chip, ad7291_threshold_reg(chan, dir, info), &uval); if (ret < 0) return ret; if (info == IIO_EV_INFO_HYSTERESIS || chan->type == IIO_VOLTAGE) *val = uval & AD7291_VALUE_MASK; else *val = sign_extend32(uval, 11); return IIO_VAL_INT; }

Contributors

PersonTokensPropCommitsCommitProp
Lars-Peter Clausen4942.98%450.00%
Sonic Zhang3631.58%112.50%
Jonathan Cameron2824.56%225.00%
Michael Hennerich10.88%112.50%
Total114100.00%8100.00%


static int ad7291_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) { struct ad7291_chip_info *chip = iio_priv(indio_dev); if (info == IIO_EV_INFO_HYSTERESIS || chan->type == IIO_VOLTAGE) { if (val > AD7291_VALUE_MASK || val < 0) return -EINVAL; } else { if (val > 2047 || val < -2048) return -EINVAL; } return ad7291_i2c_write(chip, ad7291_threshold_reg(chan, dir, info), val); }

Contributors

PersonTokensPropCommitsCommitProp
Lars-Peter Clausen4339.81%342.86%
Jonathan Cameron3532.41%228.57%
Sonic Zhang2926.85%114.29%
Michael Hennerich10.93%114.29%
Total108100.00%7100.00%


static int ad7291_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 ad7291_chip_info *chip = iio_priv(indio_dev); /* * To be enabled the channel must simply be on. If any are enabled * we are in continuous sampling mode */ switch (chan->type) { case IIO_VOLTAGE: return !!(chip->c_mask & BIT(15 - chan->channel)); case IIO_TEMP: /* always on */ return 1; default: return -EINVAL; } }

Contributors

PersonTokensPropCommitsCommitProp
Jonathan Cameron4153.25%114.29%
Lars-Peter Clausen1924.68%114.29%
Hartmut Knaack810.39%342.86%
Sonic Zhang79.09%114.29%
Michael Hennerich22.60%114.29%
Total77100.00%7100.00%


static int ad7291_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) { int ret = 0; struct ad7291_chip_info *chip = iio_priv(indio_dev); unsigned int mask; u16 regval; mutex_lock(&chip->state_lock); regval = chip->command; /* * To be enabled the channel must simply be on. If any are enabled * use continuous sampling mode. * Possible to disable temp as well but that makes single read tricky. */ mask = BIT(15 - chan->channel); switch (chan->type) { case IIO_VOLTAGE: if ((!state) && (chip->c_mask & mask)) chip->c_mask &= ~mask; else if (state && (!(chip->c_mask & mask))) chip->c_mask |= mask; else break; regval &= ~AD7291_AUTOCYCLE; regval |= chip->c_mask; if (chip->c_mask) /* Enable autocycle? */ regval |= AD7291_AUTOCYCLE; ret = ad7291_i2c_write(chip, AD7291_COMMAND, regval); if (ret < 0) goto error_ret; chip->command = regval; break; default: ret = -EINVAL; } error_ret: mutex_unlock(&chip->state_lock); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Jonathan Cameron13466.67%444.44%
Lars-Peter Clausen3517.41%111.11%
Sonic Zhang2713.43%111.11%
Michael Hennerich52.49%333.33%
Total201100.00%9100.00%


static int ad7291_read_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, int *val, int *val2, long mask) { int ret; struct ad7291_chip_info *chip = iio_priv(indio_dev); u16 regval; switch (mask) { case IIO_CHAN_INFO_RAW: switch (chan->type) { case IIO_VOLTAGE: mutex_lock(&chip->state_lock); /* If in autocycle mode drop through */ if (chip->command & AD7291_AUTOCYCLE) { mutex_unlock(&chip->state_lock); return -EBUSY; } /* Enable this channel alone */ regval = chip->command & (~AD7291_VOLTAGE_MASK); regval |= BIT(15 - chan->channel); ret = ad7291_i2c_write(chip, AD7291_COMMAND, regval); if (ret < 0) { mutex_unlock(&chip->state_lock); return ret; } /* Read voltage */ ret = i2c_smbus_read_word_swapped(chip->client, AD7291_VOLTAGE); if (ret < 0) { mutex_unlock(&chip->state_lock); return ret; } *val = ret & AD7291_VALUE_MASK; mutex_unlock(&chip->state_lock); return IIO_VAL_INT; case IIO_TEMP: /* Assumes tsense bit of command register always set */ ret = i2c_smbus_read_word_swapped(chip->client, AD7291_T_SENSE); if (ret < 0) return ret; *val = sign_extend32(ret, 11); return IIO_VAL_INT; default: return -EINVAL; } case IIO_CHAN_INFO_AVERAGE_RAW: ret = i2c_smbus_read_word_swapped(chip->client, AD7291_T_AVERAGE); if (ret < 0) return ret; *val = sign_extend32(ret, 11); return IIO_VAL_INT; case IIO_CHAN_INFO_SCALE: switch (chan->type) { case IIO_VOLTAGE: if (chip->reg) { int vref; vref = regulator_get_voltage(chip->reg); if (vref < 0) return vref; *val = vref / 1000; } else { *val = 2500; } *val2 = AD7291_BITS; return IIO_VAL_FRACTIONAL_LOG2; case IIO_TEMP: /* * One LSB of the ADC corresponds to 0.25 deg C. * The temperature reading is in 12-bit twos * complement format */ *val = 250; return IIO_VAL_INT; default: return -EINVAL; } default: return -EINVAL; } }

Contributors

PersonTokensPropCommitsCommitProp
Jonathan Cameron22963.09%635.29%
Lars-Peter Clausen5515.15%423.53%
Sonic Zhang5013.77%15.88%
Michael Hennerich267.16%529.41%
Hartmut Knaack30.83%15.88%
Total363100.00%17100.00%

static const struct iio_event_spec ad7291_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, .dir = IIO_EV_DIR_EITHER, .mask_separate = BIT(IIO_EV_INFO_HYSTERESIS), }, }; #define AD7291_VOLTAGE_CHAN(_chan) \ { \ .type = IIO_VOLTAGE, \ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ .indexed = 1, \ .channel = _chan, \ .event_spec = ad7291_events, \ .num_event_specs = ARRAY_SIZE(ad7291_events), \ } static const struct iio_chan_spec ad7291_channels[] = { AD7291_VOLTAGE_CHAN(0), AD7291_VOLTAGE_CHAN(1), AD7291_VOLTAGE_CHAN(2), AD7291_VOLTAGE_CHAN(3), AD7291_VOLTAGE_CHAN(4), AD7291_VOLTAGE_CHAN(5), AD7291_VOLTAGE_CHAN(6), AD7291_VOLTAGE_CHAN(7), { .type = IIO_TEMP, .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_AVERAGE_RAW) | BIT(IIO_CHAN_INFO_SCALE), .indexed = 1, .channel = 0, .event_spec = ad7291_events, .num_event_specs = ARRAY_SIZE(ad7291_events), } }; static const struct iio_info ad7291_info = { .read_raw = &ad7291_read_raw, .read_event_config = &ad7291_read_event_config, .write_event_config = &ad7291_write_event_config, .read_event_value = &ad7291_read_event_value, .write_event_value = &ad7291_write_event_value, .driver_module = THIS_MODULE, };
static int ad7291_probe(struct i2c_client *client, const struct i2c_device_id *id) { struct ad7291_platform_data *pdata = client->dev.platform_data; struct ad7291_chip_info *chip; struct iio_dev *indio_dev; int ret; indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*chip)); if (!indio_dev) return -ENOMEM; chip = iio_priv(indio_dev); if (pdata && pdata->use_external_ref) { chip->reg = devm_regulator_get(&client->dev, "vref"); if (IS_ERR(chip->reg)) return PTR_ERR(chip->reg); ret = regulator_enable(chip->reg); if (ret) return ret; } mutex_init(&chip->state_lock); /* this is only used for device removal purposes */ i2c_set_clientdata(client, indio_dev); chip->client = client; chip->command = AD7291_NOISE_DELAY | AD7291_T_SENSE_MASK | /* Tsense always enabled */ AD7291_ALERT_POLARITY; /* set irq polarity low level */ if (pdata && pdata->use_external_ref) chip->command |= AD7291_EXT_REF; indio_dev->name = id->name; indio_dev->channels = ad7291_channels; indio_dev->num_channels = ARRAY_SIZE(ad7291_channels); indio_dev->dev.parent = &client->dev; indio_dev->dev.of_node = client->dev.of_node; indio_dev->info = &ad7291_info; indio_dev->modes = INDIO_DIRECT_MODE; ret = ad7291_i2c_write(chip, AD7291_COMMAND, AD7291_RESET); if (ret) { ret = -EIO; goto error_disable_reg; } ret = ad7291_i2c_write(chip, AD7291_COMMAND, chip->command); if (ret) { ret = -EIO; goto error_disable_reg; } if (client->irq > 0) { ret = request_threaded_irq(client->irq, NULL, &ad7291_event_handler, IRQF_TRIGGER_LOW | IRQF_ONESHOT, id->name, indio_dev); if (ret) goto error_disable_reg; } ret = iio_device_register(indio_dev); if (ret) goto error_unreg_irq; return 0; error_unreg_irq: if (client->irq) free_irq(client->irq, indio_dev); error_disable_reg: if (chip->reg) regulator_disable(chip->reg); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Sonic Zhang13234.55%17.14%
Michael Hennerich11530.10%214.29%
Jonathan Cameron6918.06%642.86%
Lars-Peter Clausen266.81%17.14%
Sachin Kamat153.93%17.14%
Dan Carpenter133.40%214.29%
Matthew Ranostay123.14%17.14%
Total382100.00%14100.00%


static int ad7291_remove(struct i2c_client *client) { struct iio_dev *indio_dev = i2c_get_clientdata(client); struct ad7291_chip_info *chip = iio_priv(indio_dev); iio_device_unregister(indio_dev); if (client->irq) free_irq(client->irq, indio_dev); if (chip->reg) regulator_disable(chip->reg); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Sonic Zhang3247.76%120.00%
Michael Hennerich2334.33%120.00%
Jonathan Cameron1217.91%360.00%
Total67100.00%5100.00%

static const struct i2c_device_id ad7291_id[] = { { "ad7291", 0 }, {} }; MODULE_DEVICE_TABLE(i2c, ad7291_id); static struct i2c_driver ad7291_driver = { .driver = { .name = KBUILD_MODNAME, }, .probe = ad7291_probe, .remove = ad7291_remove, .id_table = ad7291_id, }; module_i2c_driver(ad7291_driver); MODULE_AUTHOR("Sonic Zhang <sonic.zhang@analog.com>"); MODULE_DESCRIPTION("Analog Devices AD7291 ADC driver"); MODULE_LICENSE("GPL v2");

Overall Contributors

PersonTokensPropCommitsCommitProp
Jonathan Cameron86137.91%1430.43%
Sonic Zhang66029.06%12.17%
Lars-Peter Clausen44019.37%1021.74%
Michael Hennerich2059.03%1021.74%
Hartmut Knaack572.51%48.70%
Sachin Kamat150.66%12.17%
Dan Carpenter130.57%24.35%
Matthew Ranostay120.53%12.17%
Wei Yongjun30.13%12.17%
Grégor Boirie30.13%12.17%
Paul Gortmaker20.09%12.17%
Total2271100.00%46100.00%
Directory: drivers/iio/adc
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
Created with cregit.