diff options
-rw-r--r-- | drivers/iio/adc/ti-ads1015.c | 409 |
1 files changed, 407 insertions, 2 deletions
diff --git a/drivers/iio/adc/ti-ads1015.c b/drivers/iio/adc/ti-ads1015.c index 14c573175f8e..d1210024f6bc 100644 --- a/drivers/iio/adc/ti-ads1015.c +++ b/drivers/iio/adc/ti-ads1015.c @@ -17,6 +17,7 @@ #include <linux/module.h> #include <linux/of_device.h> #include <linux/init.h> +#include <linux/irq.h> #include <linux/i2c.h> #include <linux/regmap.h> #include <linux/pm_runtime.h> @@ -28,6 +29,7 @@ #include <linux/iio/iio.h> #include <linux/iio/types.h> #include <linux/iio/sysfs.h> +#include <linux/iio/events.h> #include <linux/iio/buffer.h> #include <linux/iio/triggered_buffer.h> #include <linux/iio/trigger_consumer.h> @@ -36,17 +38,38 @@ #define ADS1015_CONV_REG 0x00 #define ADS1015_CFG_REG 0x01 +#define ADS1015_LO_THRESH_REG 0x02 +#define ADS1015_HI_THRESH_REG 0x03 +#define ADS1015_CFG_COMP_QUE_SHIFT 0 +#define ADS1015_CFG_COMP_LAT_SHIFT 2 +#define ADS1015_CFG_COMP_POL_SHIFT 3 +#define ADS1015_CFG_COMP_MODE_SHIFT 4 #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_COMP_QUE_MASK GENMASK(1, 0) +#define ADS1015_CFG_COMP_LAT_MASK BIT(2) +#define ADS1015_CFG_COMP_POL_MASK BIT(2) +#define ADS1015_CFG_COMP_MODE_MASK BIT(4) #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) +/* Comparator queue and disable field */ +#define ADS1015_CFG_COMP_DISABLE 3 + +/* Comparator polarity field */ +#define ADS1015_CFG_COMP_POL_LOW 0 +#define ADS1015_CFG_COMP_POL_HIGH 1 + +/* Comparator mode field */ +#define ADS1015_CFG_COMP_MODE_TRAD 0 +#define ADS1015_CFG_COMP_MODE_WINDOW 1 + /* device operating modes */ #define ADS1015_CONTINUOUS 0 #define ADS1015_SINGLESHOT 1 @@ -89,6 +112,30 @@ static int ads1015_fullscale_range[] = { 6144, 4096, 2048, 1024, 512, 256, 256, 256 }; +/* + * Translation from COMP_QUE field value to the number of successive readings + * exceed the threshold values before an interrupt is generated + */ +static const int ads1015_comp_queue[] = { 1, 2, 4 }; + +static const struct iio_event_spec ads1015_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), + }, { + .type = IIO_EV_TYPE_THRESH, + .dir = IIO_EV_DIR_EITHER, + .mask_separate = BIT(IIO_EV_INFO_ENABLE) | + BIT(IIO_EV_INFO_PERIOD), + }, +}; + #define ADS1015_V_CHAN(_chan, _addr) { \ .type = IIO_VOLTAGE, \ .indexed = 1, \ @@ -105,6 +152,8 @@ static int ads1015_fullscale_range[] = { .shift = 4, \ .endianness = IIO_CPU, \ }, \ + .event_spec = ads1015_events, \ + .num_event_specs = ARRAY_SIZE(ads1015_events), \ .datasheet_name = "AIN"#_chan, \ } @@ -126,6 +175,8 @@ static int ads1015_fullscale_range[] = { .shift = 4, \ .endianness = IIO_CPU, \ }, \ + .event_spec = ads1015_events, \ + .num_event_specs = ARRAY_SIZE(ads1015_events), \ .datasheet_name = "AIN"#_chan"-AIN"#_chan2, \ } @@ -144,6 +195,8 @@ static int ads1015_fullscale_range[] = { .storagebits = 16, \ .endianness = IIO_CPU, \ }, \ + .event_spec = ads1015_events, \ + .num_event_specs = ARRAY_SIZE(ads1015_events), \ .datasheet_name = "AIN"#_chan, \ } @@ -164,9 +217,17 @@ static int ads1015_fullscale_range[] = { .storagebits = 16, \ .endianness = IIO_CPU, \ }, \ + .event_spec = ads1015_events, \ + .num_event_specs = ARRAY_SIZE(ads1015_events), \ .datasheet_name = "AIN"#_chan"-AIN"#_chan2, \ } +struct ads1015_thresh_data { + unsigned int comp_queue; + int high_thresh; + int low_thresh; +}; + struct ads1015_data { struct regmap *regmap; /* @@ -176,6 +237,10 @@ struct ads1015_data { struct mutex lock; struct ads1015_channel_data channel_data[ADS1015_CHANNELS]; + unsigned int event_channel; + unsigned int comp_mode; + struct ads1015_thresh_data thresh_data[ADS1015_CHANNELS]; + unsigned int *data_rate; /* * Set to true when the ADC is switched to the continuous-conversion @@ -185,15 +250,41 @@ struct ads1015_data { bool conv_invalid; }; +static bool ads1015_event_channel_enabled(struct ads1015_data *data) +{ + return (data->event_channel != ADS1015_CHANNELS); +} + +static void ads1015_event_channel_enable(struct ads1015_data *data, int chan, + int comp_mode) +{ + WARN_ON(ads1015_event_channel_enabled(data)); + + data->event_channel = chan; + data->comp_mode = comp_mode; +} + +static void ads1015_event_channel_disable(struct ads1015_data *data, int chan) +{ + data->event_channel = ADS1015_CHANNELS; +} + static bool ads1015_is_writeable_reg(struct device *dev, unsigned int reg) { - return (reg == ADS1015_CFG_REG); + switch (reg) { + case ADS1015_CFG_REG: + case ADS1015_LO_THRESH_REG: + case ADS1015_HI_THRESH_REG: + return true; + default: + return false; + } } static const struct regmap_config ads1015_regmap_config = { .reg_bits = 8, .val_bits = 16, - .max_register = ADS1015_CFG_REG, + .max_register = ADS1015_HI_THRESH_REG, .writeable_reg = ads1015_is_writeable_reg, }; @@ -258,6 +349,14 @@ int ads1015_get_adc_result(struct ads1015_data *data, int chan, int *val) cfg = chan << ADS1015_CFG_MUX_SHIFT | pga << ADS1015_CFG_PGA_SHIFT | dr << ADS1015_CFG_DR_SHIFT; + if (ads1015_event_channel_enabled(data)) { + mask |= ADS1015_CFG_COMP_QUE_MASK | ADS1015_CFG_COMP_MODE_MASK; + cfg |= data->thresh_data[chan].comp_queue << + ADS1015_CFG_COMP_QUE_SHIFT | + data->comp_mode << + ADS1015_CFG_COMP_MODE_SHIFT; + } + cfg = (old & ~mask) | (cfg & mask); ret = regmap_write(data->regmap, ADS1015_CFG_REG, cfg); @@ -356,6 +455,12 @@ static int ads1015_read_raw(struct iio_dev *indio_dev, if (ret) break; + if (ads1015_event_channel_enabled(data) && + data->event_channel != chan->address) { + ret = -EBUSY; + goto release_direct; + } + ret = ads1015_set_power_state(data, true); if (ret < 0) goto release_direct; @@ -421,8 +526,254 @@ static int ads1015_write_raw(struct iio_dev *indio_dev, return ret; } +static int ads1015_read_event(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 ads1015_data *data = iio_priv(indio_dev); + int ret; + unsigned int comp_queue; + int period; + int dr; + + mutex_lock(&data->lock); + + switch (info) { + case IIO_EV_INFO_VALUE: + *val = (dir == IIO_EV_DIR_RISING) ? + data->thresh_data[chan->address].high_thresh : + data->thresh_data[chan->address].low_thresh; + ret = IIO_VAL_INT; + break; + case IIO_EV_INFO_PERIOD: + dr = data->channel_data[chan->address].data_rate; + comp_queue = data->thresh_data[chan->address].comp_queue; + period = ads1015_comp_queue[comp_queue] * + USEC_PER_SEC / data->data_rate[dr]; + + *val = period / USEC_PER_SEC; + *val2 = period % USEC_PER_SEC; + ret = IIO_VAL_INT_PLUS_MICRO; + break; + default: + ret = -EINVAL; + break; + } + + mutex_unlock(&data->lock); + + return ret; +} + +static int ads1015_write_event(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 ads1015_data *data = iio_priv(indio_dev); + int realbits = chan->scan_type.realbits; + int ret = 0; + long long period; + int i; + int dr; + + mutex_lock(&data->lock); + + switch (info) { + case IIO_EV_INFO_VALUE: + if (val >= 1 << (realbits - 1) || val < -1 << (realbits - 1)) { + ret = -EINVAL; + break; + } + if (dir == IIO_EV_DIR_RISING) + data->thresh_data[chan->address].high_thresh = val; + else + data->thresh_data[chan->address].low_thresh = val; + break; + case IIO_EV_INFO_PERIOD: + dr = data->channel_data[chan->address].data_rate; + period = val * USEC_PER_SEC + val2; + + for (i = 0; i < ARRAY_SIZE(ads1015_comp_queue) - 1; i++) { + if (period <= ads1015_comp_queue[i] * + USEC_PER_SEC / data->data_rate[dr]) + break; + } + data->thresh_data[chan->address].comp_queue = i; + break; + default: + ret = -EINVAL; + break; + } + + mutex_unlock(&data->lock); + + return ret; +} + +static int ads1015_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 ads1015_data *data = iio_priv(indio_dev); + int ret = 0; + + mutex_lock(&data->lock); + if (data->event_channel == chan->address) { + switch (dir) { + case IIO_EV_DIR_RISING: + ret = 1; + break; + case IIO_EV_DIR_EITHER: + ret = (data->comp_mode == ADS1015_CFG_COMP_MODE_WINDOW); + break; + default: + ret = -EINVAL; + break; + } + } + mutex_unlock(&data->lock); + + return ret; +} + +static int ads1015_enable_event_config(struct ads1015_data *data, + const struct iio_chan_spec *chan, int comp_mode) +{ + int low_thresh = data->thresh_data[chan->address].low_thresh; + int high_thresh = data->thresh_data[chan->address].high_thresh; + int ret; + unsigned int val; + + if (ads1015_event_channel_enabled(data)) { + if (data->event_channel != chan->address || + (data->comp_mode == ADS1015_CFG_COMP_MODE_TRAD && + comp_mode == ADS1015_CFG_COMP_MODE_WINDOW)) + return -EBUSY; + + return 0; + } + + if (comp_mode == ADS1015_CFG_COMP_MODE_TRAD) { + low_thresh = max(-1 << (chan->scan_type.realbits - 1), + high_thresh - 1); + } + ret = regmap_write(data->regmap, ADS1015_LO_THRESH_REG, + low_thresh << chan->scan_type.shift); + if (ret) + return ret; + + ret = regmap_write(data->regmap, ADS1015_HI_THRESH_REG, + high_thresh << chan->scan_type.shift); + if (ret) + return ret; + + ret = ads1015_set_power_state(data, true); + if (ret < 0) + return ret; + + ads1015_event_channel_enable(data, chan->address, comp_mode); + + ret = ads1015_get_adc_result(data, chan->address, &val); + if (ret) { + ads1015_event_channel_disable(data, chan->address); + ads1015_set_power_state(data, false); + } + + return ret; +} + +static int ads1015_disable_event_config(struct ads1015_data *data, + const struct iio_chan_spec *chan, int comp_mode) +{ + int ret; + + if (!ads1015_event_channel_enabled(data)) + return 0; + + if (data->event_channel != chan->address) + return 0; + + if (data->comp_mode == ADS1015_CFG_COMP_MODE_TRAD && + comp_mode == ADS1015_CFG_COMP_MODE_WINDOW) + return 0; + + ret = regmap_update_bits(data->regmap, ADS1015_CFG_REG, + ADS1015_CFG_COMP_QUE_MASK, + ADS1015_CFG_COMP_DISABLE << + ADS1015_CFG_COMP_QUE_SHIFT); + if (ret) + return ret; + + ads1015_event_channel_disable(data, chan->address); + + return ads1015_set_power_state(data, false); +} + +static int ads1015_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 ads1015_data *data = iio_priv(indio_dev); + int ret; + int comp_mode = (dir == IIO_EV_DIR_EITHER) ? + ADS1015_CFG_COMP_MODE_WINDOW : ADS1015_CFG_COMP_MODE_TRAD; + + mutex_lock(&data->lock); + + /* Prevent from enabling both buffer and event at a time */ + ret = iio_device_claim_direct_mode(indio_dev); + if (ret) { + mutex_unlock(&data->lock); + return ret; + } + + if (state) + ret = ads1015_enable_event_config(data, chan, comp_mode); + else + ret = ads1015_disable_event_config(data, chan, comp_mode); + + iio_device_release_direct_mode(indio_dev); + mutex_unlock(&data->lock); + + return ret; +} + +static irqreturn_t ads1015_event_handler(int irq, void *priv) +{ + struct iio_dev *indio_dev = priv; + struct ads1015_data *data = iio_priv(indio_dev); + int val; + int ret; + + /* Clear the latched ALERT/RDY pin */ + ret = regmap_read(data->regmap, ADS1015_CONV_REG, &val); + if (ret) + return IRQ_HANDLED; + + if (ads1015_event_channel_enabled(data)) { + enum iio_event_direction dir; + u64 code; + + dir = data->comp_mode == ADS1015_CFG_COMP_MODE_TRAD ? + IIO_EV_DIR_RISING : IIO_EV_DIR_EITHER; + code = IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE, data->event_channel, + IIO_EV_TYPE_THRESH, dir); + iio_push_event(indio_dev, code, iio_get_time_ns(indio_dev)); + } + + return IRQ_HANDLED; +} + static int ads1015_buffer_preenable(struct iio_dev *indio_dev) { + struct ads1015_data *data = iio_priv(indio_dev); + + /* Prevent from enabling both buffer and event at a time */ + if (ads1015_event_channel_enabled(data)) + return -EBUSY; + return ads1015_set_power_state(iio_priv(indio_dev), true); } @@ -473,6 +824,10 @@ static const struct iio_info ads1015_info = { .driver_module = THIS_MODULE, .read_raw = ads1015_read_raw, .write_raw = ads1015_write_raw, + .read_event_value = ads1015_read_event, + .write_event_value = ads1015_write_event, + .read_event_config = ads1015_read_event_config, + .write_event_config = ads1015_write_event_config, .attrs = &ads1015_attribute_group, }; @@ -480,6 +835,10 @@ static const struct iio_info ads1115_info = { .driver_module = THIS_MODULE, .read_raw = ads1015_read_raw, .write_raw = ads1015_write_raw, + .read_event_value = ads1015_read_event, + .write_event_value = ads1015_write_event, + .read_event_config = ads1015_read_event_config, + .write_event_config = ads1015_write_event_config, .attrs = &ads1115_attribute_group, }; @@ -583,6 +942,7 @@ static int ads1015_probe(struct i2c_client *client, struct ads1015_data *data; int ret; enum chip_ids chip; + int i; indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data)); if (!indio_dev) @@ -617,6 +977,18 @@ static int ads1015_probe(struct i2c_client *client, break; } + data->event_channel = ADS1015_CHANNELS; + /* + * Set default lower and upper threshold to min and max value + * respectively. + */ + for (i = 0; i < ADS1015_CHANNELS; i++) { + int realbits = indio_dev->channels[i].scan_type.realbits; + + data->thresh_data[i].low_thresh = -1 << (realbits - 1); + data->thresh_data[i].high_thresh = (1 << (realbits - 1)) - 1; + } + /* we need to keep this ABI the same as used by hwmon ADS1015 driver */ ads1015_get_channels_config(client); @@ -634,6 +1006,39 @@ static int ads1015_probe(struct i2c_client *client, return ret; } + if (client->irq) { + unsigned long irq_trig = + irqd_get_trigger_type(irq_get_irq_data(client->irq)); + unsigned int cfg_comp_mask = ADS1015_CFG_COMP_QUE_MASK | + ADS1015_CFG_COMP_LAT_MASK | ADS1015_CFG_COMP_POL_MASK; + unsigned int cfg_comp = + ADS1015_CFG_COMP_DISABLE << ADS1015_CFG_COMP_QUE_SHIFT | + 1 << ADS1015_CFG_COMP_LAT_SHIFT; + + switch (irq_trig) { + case IRQF_TRIGGER_LOW: + cfg_comp |= ADS1015_CFG_COMP_POL_LOW; + break; + case IRQF_TRIGGER_HIGH: + cfg_comp |= ADS1015_CFG_COMP_POL_HIGH; + break; + default: + return -EINVAL; + } + + ret = regmap_update_bits(data->regmap, ADS1015_CFG_REG, + cfg_comp_mask, cfg_comp); + if (ret) + return ret; + + ret = devm_request_threaded_irq(&client->dev, client->irq, + NULL, ads1015_event_handler, + irq_trig | IRQF_ONESHOT, + client->name, indio_dev); + if (ret) + return ret; + } + ret = ads1015_set_conv_mode(data, ADS1015_CONTINUOUS); if (ret) return ret; |