Provide a way for continuous data capture by setting up buffer support. The data ready signal exposed at the DRDY pin of the ADXL355 is exploited as a hardware interrupt which triggers to fill the buffer. Signed-off-by: Puranjay Mohan <puranjay12@xxxxxxxxx> --- drivers/iio/accel/Kconfig | 4 ++ drivers/iio/accel/adxl355.h | 2 +- drivers/iio/accel/adxl355_core.c | 102 ++++++++++++++++++++++++++++++- drivers/iio/accel/adxl355_i2c.c | 3 +- drivers/iio/accel/adxl355_spi.c | 2 +- 5 files changed, 108 insertions(+), 5 deletions(-) diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig index d0c45c809..9c16c1841 100644 --- a/drivers/iio/accel/Kconfig +++ b/drivers/iio/accel/Kconfig @@ -69,6 +69,8 @@ config ADXL355_I2C depends on I2C select ADXL355 select REGMAP_I2C + select IIO_BUFFER + select IIO_TRIGGERED_BUFFER help Say Y here if you want to build i2c support for the Analog Devices ADXL355 3-axis digital accelerometer. @@ -82,6 +84,8 @@ config ADXL355_SPI depends on SPI select ADXL355 select REGMAP_SPI + select IIO_BUFFER + select IIO_TRIGGERED_BUFFER help Say Y here if you want to build spi support for the Analog Devices ADXL355 3-axis digital accelerometer. diff --git a/drivers/iio/accel/adxl355.h b/drivers/iio/accel/adxl355.h index 322b0abb8..f0a376e6d 100644 --- a/drivers/iio/accel/adxl355.h +++ b/drivers/iio/accel/adxl355.h @@ -15,5 +15,5 @@ extern const struct regmap_access_table adxl355_readable_regs_tbl; extern const struct regmap_access_table adxl355_writeable_regs_tbl; int adxl355_core_probe(struct device *dev, struct regmap *regmap, - const char *name); + const char *name, int irq); #endif /* _ADXL355_H_ */ diff --git a/drivers/iio/accel/adxl355_core.c b/drivers/iio/accel/adxl355_core.c index 47fbb31bc..f9dc2a530 100644 --- a/drivers/iio/accel/adxl355_core.c +++ b/drivers/iio/accel/adxl355_core.c @@ -9,6 +9,10 @@ #include <asm/unaligned.h> #include <linux/bitfield.h> +#include <linux/iio/buffer.h> +#include <linux/iio/trigger.h> +#include <linux/iio/triggered_buffer.h> +#include <linux/iio/trigger_consumer.h> #include <linux/iio/iio.h> #include <linux/limits.h> #include <linux/math64.h> @@ -172,6 +176,7 @@ static const struct adxl355_chan_info adxl355_chans[] = { }; struct adxl355_data { + int irq; struct regmap *regmap; struct device *dev; struct mutex lock; /* lock to protect op_mode */ @@ -181,6 +186,12 @@ struct adxl355_data { int calibbias[3]; int adxl355_hpf_3db_table[7][2]; u8 transf_buf[3] ____cacheline_aligned; + struct iio_trigger *dready_trig; + /* Ensure correct alignment of timestamp when present */ + struct { + __be32 channels[3]; + s64 ts; + } buffer ____cacheline_aligned; }; static int adxl355_set_op_mode(struct adxl355_data *data, @@ -499,12 +510,46 @@ static int adxl355_read_avail(struct iio_dev *indio_dev, } } +static const unsigned long adxl355_avail_scan_masks[] = { + GENMASK(3, 0), + 0 +}; + static const struct iio_info adxl355_info = { .read_raw = adxl355_read_raw, .write_raw = adxl355_write_raw, .read_avail = &adxl355_read_avail }; +static const struct iio_trigger_ops adxl355_trigger_ops = { + .validate_device = &iio_trigger_validate_own_device, +}; + +static irqreturn_t adxl355_trigger_handler(int irq, void *p) +{ + struct iio_poll_func *pf = p; + struct iio_dev *indio_dev = pf->indio_dev; + struct adxl355_data *data = iio_priv(indio_dev); + int ret; + + mutex_lock(&data->lock); + + ret = regmap_bulk_read(data->regmap, ADXL355_XDATA3_REG, + data->buffer.channels, + 9); + if (ret) + goto out_unlock_notify; + + iio_push_to_buffers_with_timestamp(indio_dev, &data->buffer, + pf->timestamp); + +out_unlock_notify: + mutex_unlock(&data->lock); + iio_trigger_notify_done(indio_dev->trig); + + return IRQ_HANDLED; +} + #define ADXL355_ACCEL_CHANNEL(index, reg, axis) { \ .type = IIO_ACCEL, \ .address = reg, \ @@ -518,6 +563,7 @@ static const struct iio_info adxl355_info = { .info_mask_shared_by_type_available = \ BIT(IIO_CHAN_INFO_SAMP_FREQ) | \ BIT(IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY), \ + .scan_index = index, \ .scan_type = { \ .sign = 's', \ .realbits = 20, \ @@ -537,17 +583,56 @@ static const struct iio_chan_spec adxl355_channels[] = { .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE) | BIT(IIO_CHAN_INFO_OFFSET), + .scan_index = 3, .scan_type = { .sign = 's', .realbits = 12, .storagebits = 16, .endianness = IIO_BE, }, - } + }, + IIO_CHAN_SOFT_TIMESTAMP(4) }; +static int adxl355_probe_trigger(struct iio_dev *indio_dev) +{ + struct adxl355_data *data = iio_priv(indio_dev); + int ret; + + if (!data->irq) { + dev_info(data->dev, "no irq, using polling\n"); + return 0; + } + + data->dready_trig = devm_iio_trigger_alloc(data->dev, "%s-dev%d", + indio_dev->name, + indio_dev->id); + if (!data->dready_trig) + return -ENOMEM; + + data->dready_trig->ops = &adxl355_trigger_ops; + iio_trigger_set_drvdata(data->dready_trig, indio_dev); + + ret = devm_request_irq(data->dev, data->irq, + &iio_trigger_generic_data_rdy_poll, + IRQF_ONESHOT, "adxl355_irq", data->dready_trig); + if (ret < 0) + return dev_err_probe(data->dev, ret, "request irq %d failed\n", + data->irq); + + ret = devm_iio_trigger_register(data->dev, data->dready_trig); + if (ret) { + dev_err(data->dev, "iio trigger register failed\n"); + return ret; + } + + indio_dev->trig = iio_trigger_get(data->dready_trig); + + return 0; +} + int adxl355_core_probe(struct device *dev, struct regmap *regmap, - const char *name) + const char *name, int irq) { struct adxl355_data *data; struct iio_dev *indio_dev; @@ -560,6 +645,7 @@ int adxl355_core_probe(struct device *dev, struct regmap *regmap, data = iio_priv(indio_dev); data->regmap = regmap; data->dev = dev; + data->irq = irq; data->op_mode = ADXL355_STANDBY; mutex_init(&data->lock); @@ -568,6 +654,7 @@ int adxl355_core_probe(struct device *dev, struct regmap *regmap, indio_dev->modes = INDIO_DIRECT_MODE; indio_dev->channels = adxl355_channels; indio_dev->num_channels = ARRAY_SIZE(adxl355_channels); + indio_dev->available_scan_masks = adxl355_avail_scan_masks; ret = adxl355_setup(data); if (ret < 0) { @@ -575,6 +662,17 @@ int adxl355_core_probe(struct device *dev, struct regmap *regmap, return ret; } + ret = devm_iio_triggered_buffer_setup(dev, indio_dev, + &iio_pollfunc_store_time, + &adxl355_trigger_handler, NULL); + if (ret < 0) + return dev_err_probe(dev, ret, + "iio triggered buffer setup failed\n"); + + ret = adxl355_probe_trigger(indio_dev); + if (ret < 0) + return ret; + return devm_iio_device_register(dev, indio_dev); } EXPORT_SYMBOL_GPL(adxl355_core_probe); diff --git a/drivers/iio/accel/adxl355_i2c.c b/drivers/iio/accel/adxl355_i2c.c index e3070ee81..c18521819 100644 --- a/drivers/iio/accel/adxl355_i2c.c +++ b/drivers/iio/accel/adxl355_i2c.c @@ -31,7 +31,8 @@ static int adxl355_i2c_probe(struct i2c_client *client) return PTR_ERR(regmap); } - return adxl355_core_probe(&client->dev, regmap, client->name); + return adxl355_core_probe(&client->dev, regmap, client->name, + client->irq); } static const struct i2c_device_id adxl355_i2c_id[] = { diff --git a/drivers/iio/accel/adxl355_spi.c b/drivers/iio/accel/adxl355_spi.c index a16bd1407..f9ba153f6 100644 --- a/drivers/iio/accel/adxl355_spi.c +++ b/drivers/iio/accel/adxl355_spi.c @@ -34,7 +34,7 @@ static int adxl355_spi_probe(struct spi_device *spi) return PTR_ERR(regmap); } - return adxl355_core_probe(&spi->dev, regmap, id->name); + return adxl355_core_probe(&spi->dev, regmap, id->name, spi->irq); } static const struct spi_device_id adxl355_spi_id[] = { -- 2.30.1