From d635711daa98be86d4c7fd01499c34f566b54ccb Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Fri, 10 Jun 2016 05:30:17 -0300 Subject: Linux-libre 4.6.2-gnu --- drivers/iio/adc/ti-ads1015.c | 612 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 612 insertions(+) create mode 100644 drivers/iio/adc/ti-ads1015.c (limited to 'drivers/iio/adc/ti-ads1015.c') diff --git a/drivers/iio/adc/ti-ads1015.c b/drivers/iio/adc/ti-ads1015.c new file mode 100644 index 000000000..73cbf0b54 --- /dev/null +++ b/drivers/iio/adc/ti-ads1015.c @@ -0,0 +1,612 @@ +/* + * ADS1015 - Texas Instruments Analog-to-Digital Converter + * + * Copyright (c) 2016, Intel Corporation. + * + * This file is subject to the terms and conditions of version 2 of + * the GNU General Public License. See the file COPYING in the main + * directory of this archive for more details. + * + * IIO driver for ADS1015 ADC 7-bit I2C slave address: + * * 0x48 - ADDR connected to Ground + * * 0x49 - ADDR connected to Vdd + * * 0x4A - ADDR connected to SDA + * * 0x4B - ADDR connected to SCL + */ + +#include +#include +#include +#include +#include +#include +#include + +#include + +#include +#include +#include +#include +#include +#include + +#define ADS1015_DRV_NAME "ads1015" + +#define ADS1015_CONV_REG 0x00 +#define ADS1015_CFG_REG 0x01 + +#define ADS1015_CFG_DR_SHIFT 5 +#define ADS1015_CFG_MOD_SHIFT 8 +#define ADS1015_CFG_PGA_SHIFT 9 +#define ADS1015_CFG_MUX_SHIFT 12 + +#define ADS1015_CFG_DR_MASK GENMASK(7, 5) +#define ADS1015_CFG_MOD_MASK BIT(8) +#define ADS1015_CFG_PGA_MASK GENMASK(11, 9) +#define ADS1015_CFG_MUX_MASK GENMASK(14, 12) + +/* device operating modes */ +#define ADS1015_CONTINUOUS 0 +#define ADS1015_SINGLESHOT 1 + +#define ADS1015_SLEEP_DELAY_MS 2000 +#define ADS1015_DEFAULT_PGA 2 +#define ADS1015_DEFAULT_DATA_RATE 4 +#define ADS1015_DEFAULT_CHAN 0 + +enum ads1015_channels { + ADS1015_AIN0_AIN1 = 0, + ADS1015_AIN0_AIN3, + ADS1015_AIN1_AIN3, + ADS1015_AIN2_AIN3, + ADS1015_AIN0, + ADS1015_AIN1, + ADS1015_AIN2, + ADS1015_AIN3, + ADS1015_TIMESTAMP, +}; + +static const unsigned int ads1015_data_rate[] = { + 128, 250, 490, 920, 1600, 2400, 3300, 3300 +}; + +static const struct { + int scale; + int uscale; +} ads1015_scale[] = { + {3, 0}, + {2, 0}, + {1, 0}, + {0, 500000}, + {0, 250000}, + {0, 125000}, + {0, 125000}, + {0, 125000}, +}; + +#define ADS1015_V_CHAN(_chan, _addr) { \ + .type = IIO_VOLTAGE, \ + .indexed = 1, \ + .address = _addr, \ + .channel = _chan, \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ + BIT(IIO_CHAN_INFO_SCALE) | \ + BIT(IIO_CHAN_INFO_SAMP_FREQ), \ + .scan_index = _addr, \ + .scan_type = { \ + .sign = 's', \ + .realbits = 12, \ + .storagebits = 16, \ + .shift = 4, \ + .endianness = IIO_CPU, \ + }, \ +} + +#define ADS1015_V_DIFF_CHAN(_chan, _chan2, _addr) { \ + .type = IIO_VOLTAGE, \ + .differential = 1, \ + .indexed = 1, \ + .address = _addr, \ + .channel = _chan, \ + .channel2 = _chan2, \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ + BIT(IIO_CHAN_INFO_SCALE) | \ + BIT(IIO_CHAN_INFO_SAMP_FREQ), \ + .scan_index = _addr, \ + .scan_type = { \ + .sign = 's', \ + .realbits = 12, \ + .storagebits = 16, \ + .shift = 4, \ + .endianness = IIO_CPU, \ + }, \ +} + +struct ads1015_data { + struct regmap *regmap; + /* + * Protects ADC ops, e.g: concurrent sysfs/buffered + * data reads, configuration updates + */ + struct mutex lock; + struct ads1015_channel_data channel_data[ADS1015_CHANNELS]; +}; + +static bool ads1015_is_writeable_reg(struct device *dev, unsigned int reg) +{ + return (reg == ADS1015_CFG_REG); +} + +static const struct regmap_config ads1015_regmap_config = { + .reg_bits = 8, + .val_bits = 16, + .max_register = ADS1015_CFG_REG, + .writeable_reg = ads1015_is_writeable_reg, +}; + +static const struct iio_chan_spec ads1015_channels[] = { + ADS1015_V_DIFF_CHAN(0, 1, ADS1015_AIN0_AIN1), + ADS1015_V_DIFF_CHAN(0, 3, ADS1015_AIN0_AIN3), + ADS1015_V_DIFF_CHAN(1, 3, ADS1015_AIN1_AIN3), + ADS1015_V_DIFF_CHAN(2, 3, ADS1015_AIN2_AIN3), + ADS1015_V_CHAN(0, ADS1015_AIN0), + ADS1015_V_CHAN(1, ADS1015_AIN1), + ADS1015_V_CHAN(2, ADS1015_AIN2), + ADS1015_V_CHAN(3, ADS1015_AIN3), + IIO_CHAN_SOFT_TIMESTAMP(ADS1015_TIMESTAMP), +}; + +static int ads1015_set_power_state(struct ads1015_data *data, bool on) +{ + int ret; + struct device *dev = regmap_get_device(data->regmap); + + if (on) { + ret = pm_runtime_get_sync(dev); + if (ret < 0) + pm_runtime_put_noidle(dev); + } else { + pm_runtime_mark_last_busy(dev); + ret = pm_runtime_put_autosuspend(dev); + } + + return ret; +} + +static +int ads1015_get_adc_result(struct ads1015_data *data, int chan, int *val) +{ + int ret, pga, dr, conv_time; + bool change; + + if (chan < 0 || chan >= ADS1015_CHANNELS) + return -EINVAL; + + pga = data->channel_data[chan].pga; + dr = data->channel_data[chan].data_rate; + + ret = regmap_update_bits_check(data->regmap, ADS1015_CFG_REG, + ADS1015_CFG_MUX_MASK | + ADS1015_CFG_PGA_MASK, + chan << ADS1015_CFG_MUX_SHIFT | + pga << ADS1015_CFG_PGA_SHIFT, + &change); + if (ret < 0) + return ret; + + if (change) { + conv_time = DIV_ROUND_UP(USEC_PER_SEC, ads1015_data_rate[dr]); + usleep_range(conv_time, conv_time + 1); + } + + return regmap_read(data->regmap, ADS1015_CONV_REG, val); +} + +static irqreturn_t ads1015_trigger_handler(int irq, void *p) +{ + struct iio_poll_func *pf = p; + struct iio_dev *indio_dev = pf->indio_dev; + struct ads1015_data *data = iio_priv(indio_dev); + s16 buf[8]; /* 1x s16 ADC val + 3x s16 padding + 4x s16 timestamp */ + int chan, ret, res; + + memset(buf, 0, sizeof(buf)); + + mutex_lock(&data->lock); + chan = find_first_bit(indio_dev->active_scan_mask, + indio_dev->masklength); + ret = ads1015_get_adc_result(data, chan, &res); + if (ret < 0) { + mutex_unlock(&data->lock); + goto err; + } + + buf[0] = res; + mutex_unlock(&data->lock); + + iio_push_to_buffers_with_timestamp(indio_dev, buf, iio_get_time_ns()); + +err: + iio_trigger_notify_done(indio_dev->trig); + + return IRQ_HANDLED; +} + +static int ads1015_set_scale(struct ads1015_data *data, int chan, + int scale, int uscale) +{ + int i, ret, rindex = -1; + + for (i = 0; i < ARRAY_SIZE(ads1015_scale); i++) + if (ads1015_scale[i].scale == scale && + ads1015_scale[i].uscale == uscale) { + rindex = i; + break; + } + if (rindex < 0) + return -EINVAL; + + ret = regmap_update_bits(data->regmap, ADS1015_CFG_REG, + ADS1015_CFG_PGA_MASK, + rindex << ADS1015_CFG_PGA_SHIFT); + if (ret < 0) + return ret; + + data->channel_data[chan].pga = rindex; + + return 0; +} + +static int ads1015_set_data_rate(struct ads1015_data *data, int chan, int rate) +{ + int i, ret, rindex = -1; + + for (i = 0; i < ARRAY_SIZE(ads1015_data_rate); i++) + if (ads1015_data_rate[i] == rate) { + rindex = i; + break; + } + if (rindex < 0) + return -EINVAL; + + ret = regmap_update_bits(data->regmap, ADS1015_CFG_REG, + ADS1015_CFG_DR_MASK, + rindex << ADS1015_CFG_DR_SHIFT); + if (ret < 0) + return ret; + + data->channel_data[chan].data_rate = rindex; + + return 0; +} + +static int ads1015_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, int *val, + int *val2, long mask) +{ + int ret, idx; + struct ads1015_data *data = iio_priv(indio_dev); + + mutex_lock(&indio_dev->mlock); + mutex_lock(&data->lock); + switch (mask) { + case IIO_CHAN_INFO_RAW: + if (iio_buffer_enabled(indio_dev)) { + ret = -EBUSY; + break; + } + + ret = ads1015_set_power_state(data, true); + if (ret < 0) + break; + + ret = ads1015_get_adc_result(data, chan->address, val); + if (ret < 0) { + ads1015_set_power_state(data, false); + break; + } + + /* 12 bit res, D0 is bit 4 in conversion register */ + *val = sign_extend32(*val >> 4, 11); + + ret = ads1015_set_power_state(data, false); + if (ret < 0) + break; + + ret = IIO_VAL_INT; + break; + case IIO_CHAN_INFO_SCALE: + idx = data->channel_data[chan->address].pga; + *val = ads1015_scale[idx].scale; + *val2 = ads1015_scale[idx].uscale; + ret = IIO_VAL_INT_PLUS_MICRO; + break; + case IIO_CHAN_INFO_SAMP_FREQ: + idx = data->channel_data[chan->address].data_rate; + *val = ads1015_data_rate[idx]; + ret = IIO_VAL_INT; + break; + default: + ret = -EINVAL; + break; + } + mutex_unlock(&data->lock); + mutex_unlock(&indio_dev->mlock); + + return ret; +} + +static int ads1015_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, int val, + int val2, long mask) +{ + struct ads1015_data *data = iio_priv(indio_dev); + int ret; + + mutex_lock(&data->lock); + switch (mask) { + case IIO_CHAN_INFO_SCALE: + ret = ads1015_set_scale(data, chan->address, val, val2); + break; + case IIO_CHAN_INFO_SAMP_FREQ: + ret = ads1015_set_data_rate(data, chan->address, val); + break; + default: + ret = -EINVAL; + break; + } + mutex_unlock(&data->lock); + + return ret; +} + +static int ads1015_buffer_preenable(struct iio_dev *indio_dev) +{ + return ads1015_set_power_state(iio_priv(indio_dev), true); +} + +static int ads1015_buffer_postdisable(struct iio_dev *indio_dev) +{ + return ads1015_set_power_state(iio_priv(indio_dev), false); +} + +static const struct iio_buffer_setup_ops ads1015_buffer_setup_ops = { + .preenable = ads1015_buffer_preenable, + .postenable = iio_triggered_buffer_postenable, + .predisable = iio_triggered_buffer_predisable, + .postdisable = ads1015_buffer_postdisable, + .validate_scan_mask = &iio_validate_scan_mask_onehot, +}; + +static IIO_CONST_ATTR(scale_available, "3 2 1 0.5 0.25 0.125"); +static IIO_CONST_ATTR(sampling_frequency_available, + "128 250 490 920 1600 2400 3300"); + +static struct attribute *ads1015_attributes[] = { + &iio_const_attr_scale_available.dev_attr.attr, + &iio_const_attr_sampling_frequency_available.dev_attr.attr, + NULL, +}; + +static const struct attribute_group ads1015_attribute_group = { + .attrs = ads1015_attributes, +}; + +static const struct iio_info ads1015_info = { + .driver_module = THIS_MODULE, + .read_raw = ads1015_read_raw, + .write_raw = ads1015_write_raw, + .attrs = &ads1015_attribute_group, +}; + +#ifdef CONFIG_OF +static int ads1015_get_channels_config_of(struct i2c_client *client) +{ + struct ads1015_data *data = i2c_get_clientdata(client); + struct device_node *node; + + if (!client->dev.of_node || + !of_get_next_child(client->dev.of_node, NULL)) + return -EINVAL; + + for_each_child_of_node(client->dev.of_node, node) { + u32 pval; + unsigned int channel; + unsigned int pga = ADS1015_DEFAULT_PGA; + unsigned int data_rate = ADS1015_DEFAULT_DATA_RATE; + + if (of_property_read_u32(node, "reg", &pval)) { + dev_err(&client->dev, "invalid reg on %s\n", + node->full_name); + continue; + } + + channel = pval; + if (channel >= ADS1015_CHANNELS) { + dev_err(&client->dev, + "invalid channel index %d on %s\n", + channel, node->full_name); + continue; + } + + if (!of_property_read_u32(node, "ti,gain", &pval)) { + pga = pval; + if (pga > 6) { + dev_err(&client->dev, "invalid gain on %s\n", + node->full_name); + return -EINVAL; + } + } + + if (!of_property_read_u32(node, "ti,datarate", &pval)) { + data_rate = pval; + if (data_rate > 7) { + dev_err(&client->dev, + "invalid data_rate on %s\n", + node->full_name); + return -EINVAL; + } + } + + data->channel_data[channel].pga = pga; + data->channel_data[channel].data_rate = data_rate; + } + + return 0; +} +#endif + +static void ads1015_get_channels_config(struct i2c_client *client) +{ + unsigned int k; + + struct iio_dev *indio_dev = i2c_get_clientdata(client); + struct ads1015_data *data = iio_priv(indio_dev); + struct ads1015_platform_data *pdata = dev_get_platdata(&client->dev); + + /* prefer platform data */ + if (pdata) { + memcpy(data->channel_data, pdata->channel_data, + sizeof(data->channel_data)); + return; + } + +#ifdef CONFIG_OF + if (!ads1015_get_channels_config_of(client)) + return; +#endif + /* fallback on default configuration */ + for (k = 0; k < ADS1015_CHANNELS; ++k) { + data->channel_data[k].pga = ADS1015_DEFAULT_PGA; + data->channel_data[k].data_rate = ADS1015_DEFAULT_DATA_RATE; + } +} + +static int ads1015_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct iio_dev *indio_dev; + struct ads1015_data *data; + int ret; + + indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data)); + if (!indio_dev) + return -ENOMEM; + + data = iio_priv(indio_dev); + i2c_set_clientdata(client, indio_dev); + + mutex_init(&data->lock); + + indio_dev->dev.parent = &client->dev; + indio_dev->info = &ads1015_info; + indio_dev->name = ADS1015_DRV_NAME; + indio_dev->channels = ads1015_channels; + indio_dev->num_channels = ARRAY_SIZE(ads1015_channels); + indio_dev->modes = INDIO_DIRECT_MODE; + + /* we need to keep this ABI the same as used by hwmon ADS1015 driver */ + ads1015_get_channels_config(client); + + data->regmap = devm_regmap_init_i2c(client, &ads1015_regmap_config); + if (IS_ERR(data->regmap)) { + dev_err(&client->dev, "Failed to allocate register map\n"); + return PTR_ERR(data->regmap); + } + + ret = iio_triggered_buffer_setup(indio_dev, NULL, + ads1015_trigger_handler, + &ads1015_buffer_setup_ops); + if (ret < 0) { + dev_err(&client->dev, "iio triggered buffer setup failed\n"); + return ret; + } + ret = pm_runtime_set_active(&client->dev); + if (ret) + goto err_buffer_cleanup; + pm_runtime_set_autosuspend_delay(&client->dev, ADS1015_SLEEP_DELAY_MS); + pm_runtime_use_autosuspend(&client->dev); + pm_runtime_enable(&client->dev); + + ret = iio_device_register(indio_dev); + if (ret < 0) { + dev_err(&client->dev, "Failed to register IIO device\n"); + goto err_buffer_cleanup; + } + + return 0; + +err_buffer_cleanup: + iio_triggered_buffer_cleanup(indio_dev); + + return ret; +} + +static int ads1015_remove(struct i2c_client *client) +{ + struct iio_dev *indio_dev = i2c_get_clientdata(client); + struct ads1015_data *data = iio_priv(indio_dev); + + iio_device_unregister(indio_dev); + + pm_runtime_disable(&client->dev); + pm_runtime_set_suspended(&client->dev); + pm_runtime_put_noidle(&client->dev); + + iio_triggered_buffer_cleanup(indio_dev); + + /* power down single shot mode */ + return regmap_update_bits(data->regmap, ADS1015_CFG_REG, + ADS1015_CFG_MOD_MASK, + ADS1015_SINGLESHOT << ADS1015_CFG_MOD_SHIFT); +} + +#ifdef CONFIG_PM +static int ads1015_runtime_suspend(struct device *dev) +{ + struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev)); + struct ads1015_data *data = iio_priv(indio_dev); + + return regmap_update_bits(data->regmap, ADS1015_CFG_REG, + ADS1015_CFG_MOD_MASK, + ADS1015_SINGLESHOT << ADS1015_CFG_MOD_SHIFT); +} + +static int ads1015_runtime_resume(struct device *dev) +{ + struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev)); + struct ads1015_data *data = iio_priv(indio_dev); + + return regmap_update_bits(data->regmap, ADS1015_CFG_REG, + ADS1015_CFG_MOD_MASK, + ADS1015_CONTINUOUS << ADS1015_CFG_MOD_SHIFT); +} +#endif + +static const struct dev_pm_ops ads1015_pm_ops = { + SET_RUNTIME_PM_OPS(ads1015_runtime_suspend, + ads1015_runtime_resume, NULL) +}; + +static const struct i2c_device_id ads1015_id[] = { + {"ads1015", 0}, + {} +}; +MODULE_DEVICE_TABLE(i2c, ads1015_id); + +static struct i2c_driver ads1015_driver = { + .driver = { + .name = ADS1015_DRV_NAME, + .pm = &ads1015_pm_ops, + }, + .probe = ads1015_probe, + .remove = ads1015_remove, + .id_table = ads1015_id, +}; + +module_i2c_driver(ads1015_driver); + +MODULE_AUTHOR("Daniel Baluta "); +MODULE_DESCRIPTION("Texas Instruments ADS1015 ADC driver"); +MODULE_LICENSE("GPL v2"); -- cgit v1.2.3-54-g00ecf