*/
#include <linux/bitops.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
#include <linux/module.h>
#include <linux/regmap.h>
#include <linux/spi/spi.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/events.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
/* ADXL372 registers definition */
#define ADXL372_DEVID 0x00
#define ADXL372_INT1_MAP_LOW_MSK BIT(7)
#define ADXL372_INT1_MAP_LOW_MODE(x) (((x) & 0x1) << 7)
+/* The ADXL372 includes a deep, 512 sample FIFO buffer */
+#define ADXL372_FIFO_SIZE 512
+
/*
* At +/- 200g with 12-bit resolution, scale is computed as:
* (200 + 200) * 9.81 / (2^12 - 1) = 0.958241
[ADXL372_INACTIVITY] = ADXL372_X_THRESH_INACT_H,
};
+enum adxl372_fifo_format {
+ ADXL372_XYZ_FIFO,
+ ADXL372_X_FIFO,
+ ADXL372_Y_FIFO,
+ ADXL372_XY_FIFO,
+ ADXL372_Z_FIFO,
+ ADXL372_XZ_FIFO,
+ ADXL372_YZ_FIFO,
+ ADXL372_XYZ_PEAK_FIFO,
+};
+
+enum adxl372_fifo_mode {
+ ADXL372_FIFO_BYPASSED,
+ ADXL372_FIFO_STREAMED,
+ ADXL372_FIFO_TRIGGERED,
+ ADXL372_FIFO_OLD_SAVED
+};
+
+static const int adxl372_samp_freq_tbl[5] = {
+ 400, 800, 1600, 3200, 6400,
+};
+
+struct adxl372_axis_lookup {
+ unsigned int bits;
+ enum adxl372_fifo_format fifo_format;
+};
+
+static const struct adxl372_axis_lookup adxl372_axis_lookup_table[] = {
+ { BIT(0), ADXL372_X_FIFO },
+ { BIT(1), ADXL372_Y_FIFO },
+ { BIT(2), ADXL372_Z_FIFO },
+ { BIT(0) | BIT(1), ADXL372_XY_FIFO },
+ { BIT(0) | BIT(2), ADXL372_XZ_FIFO },
+ { BIT(1) | BIT(2), ADXL372_YZ_FIFO },
+ { BIT(0) | BIT(1) | BIT(2), ADXL372_XYZ_FIFO },
+};
+
#define ADXL372_ACCEL_CHANNEL(index, reg, axis) { \
.type = IIO_ACCEL, \
.address = reg, \
.channel2 = IIO_MOD_##axis, \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
+ .scan_index = index, \
+ .scan_type = { \
+ .sign = 's', \
+ .realbits = 12, \
+ .storagebits = 16, \
+ .shift = 4, \
+ }, \
}
static const struct iio_chan_spec adxl372_channels[] = {
struct adxl372_state {
struct spi_device *spi;
struct regmap *regmap;
+ struct iio_trigger *dready_trig;
+ enum adxl372_fifo_mode fifo_mode;
+ enum adxl372_fifo_format fifo_format;
enum adxl372_op_mode op_mode;
enum adxl372_act_proc_mode act_proc_mode;
enum adxl372_odr odr;
enum adxl372_bandwidth bw;
u32 act_time_ms;
u32 inact_time_ms;
+ u8 fifo_set_size;
+ u8 int1_bitmask;
+ u8 int2_bitmask;
+ u16 watermark;
+ __be16 fifo_buf[ADXL372_FIFO_SIZE];
+};
+
+static const unsigned long adxl372_channel_masks[] = {
+ BIT(0), BIT(1), BIT(2),
+ BIT(0) | BIT(1),
+ BIT(0) | BIT(2),
+ BIT(1) | BIT(2),
+ BIT(0) | BIT(1) | BIT(2),
+ 0
};
static int adxl372_read_axis(struct adxl372_state *st, u8 addr)
return ret;
}
+static int adxl372_set_interrupts(struct adxl372_state *st,
+ unsigned char int1_bitmask,
+ unsigned char int2_bitmask)
+{
+ int ret;
+
+ ret = regmap_write(st->regmap, ADXL372_INT1_MAP, int1_bitmask);
+ if (ret < 0)
+ return ret;
+
+ return regmap_write(st->regmap, ADXL372_INT2_MAP, int2_bitmask);
+}
+
+static int adxl372_configure_fifo(struct adxl372_state *st)
+{
+ unsigned int fifo_samples, fifo_ctl;
+ int ret;
+
+ /* FIFO must be configured while in standby mode */
+ ret = adxl372_set_op_mode(st, ADXL372_STANDBY);
+ if (ret < 0)
+ return ret;
+
+ fifo_samples = st->watermark & 0xFF;
+ fifo_ctl = ADXL372_FIFO_CTL_FORMAT_MODE(st->fifo_format) |
+ ADXL372_FIFO_CTL_MODE_MODE(st->fifo_mode) |
+ ADXL372_FIFO_CTL_SAMPLES_MODE(st->watermark);
+
+ ret = regmap_write(st->regmap, ADXL372_FIFO_SAMPLES, fifo_samples);
+ if (ret < 0)
+ return ret;
+
+ ret = regmap_write(st->regmap, ADXL372_FIFO_CTL, fifo_ctl);
+ if (ret < 0)
+ return ret;
+
+ return adxl372_set_op_mode(st, ADXL372_FULL_BW_MEASUREMENT);
+}
+
+static int adxl372_get_status(struct adxl372_state *st,
+ u8 *status1, u8 *status2,
+ u16 *fifo_entries)
+{
+ __be32 buf;
+ u32 val;
+ int ret;
+
+ /* STATUS1, STATUS2, FIFO_ENTRIES2 and FIFO_ENTRIES are adjacent regs */
+ ret = regmap_bulk_read(st->regmap, ADXL372_STATUS_1,
+ &buf, sizeof(buf));
+ if (ret < 0)
+ return ret;
+
+ val = be32_to_cpu(buf);
+
+ *status1 = (val >> 24) & 0x0F;
+ *status2 = (val >> 16) & 0x0F;
+ /*
+ * FIFO_ENTRIES contains the least significant byte, and FIFO_ENTRIES2
+ * contains the two most significant bits
+ */
+ *fifo_entries = val & 0x3FF;
+
+ return ret;
+}
+
+static irqreturn_t adxl372_trigger_handler(int irq, void *p)
+{
+ struct iio_poll_func *pf = p;
+ struct iio_dev *indio_dev = pf->indio_dev;
+ struct adxl372_state *st = iio_priv(indio_dev);
+ u8 status1, status2;
+ u16 fifo_entries;
+ int i, ret;
+
+ ret = adxl372_get_status(st, &status1, &status2, &fifo_entries);
+ if (ret < 0)
+ goto err;
+
+ if (st->fifo_mode != ADXL372_FIFO_BYPASSED &&
+ ADXL372_STATUS_1_FIFO_FULL(status1)) {
+ /*
+ * When reading data from multiple axes from the FIFO,
+ * to ensure that data is not overwritten and stored out
+ * of order at least one sample set must be left in the
+ * FIFO after every read.
+ */
+ fifo_entries -= st->fifo_set_size;
+
+ /* Read data from the FIFO */
+ ret = regmap_noinc_read(st->regmap, ADXL372_FIFO_DATA,
+ st->fifo_buf,
+ fifo_entries * sizeof(u16));
+ if (ret < 0)
+ goto err;
+
+ /* Each sample is 2 bytes */
+ for (i = 0; i < fifo_entries * sizeof(u16);
+ i += st->fifo_set_size * sizeof(u16))
+ iio_push_to_buffers(indio_dev, &st->fifo_buf[i]);
+ }
+err:
+ iio_trigger_notify_done(indio_dev->trig);
+ return IRQ_HANDLED;
+}
+
static int adxl372_setup(struct adxl372_state *st)
{
unsigned int regval;
switch (info) {
case IIO_CHAN_INFO_RAW:
+ ret = iio_device_claim_direct_mode(indio_dev);
+ if (ret)
+ return ret;
+
ret = adxl372_read_axis(st, chan->address);
+ iio_device_release_direct_mode(indio_dev);
if (ret < 0)
return ret;
}
}
+static ssize_t adxl372_get_fifo_enabled(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+ struct adxl372_state *st = iio_priv(indio_dev);
+
+ return sprintf(buf, "%d\n", st->fifo_mode);
+}
+
+static ssize_t adxl372_get_fifo_watermark(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+ struct adxl372_state *st = iio_priv(indio_dev);
+
+ return sprintf(buf, "%d\n", st->watermark);
+}
+
+static IIO_CONST_ATTR(hwfifo_watermark_min, "1");
+static IIO_CONST_ATTR(hwfifo_watermark_max,
+ __stringify(ADXL372_FIFO_SIZE));
+static IIO_DEVICE_ATTR(hwfifo_watermark, 0444,
+ adxl372_get_fifo_watermark, NULL, 0);
+static IIO_DEVICE_ATTR(hwfifo_enabled, 0444,
+ adxl372_get_fifo_enabled, NULL, 0);
+
+static const struct attribute *adxl372_fifo_attributes[] = {
+ &iio_const_attr_hwfifo_watermark_min.dev_attr.attr,
+ &iio_const_attr_hwfifo_watermark_max.dev_attr.attr,
+ &iio_dev_attr_hwfifo_watermark.dev_attr.attr,
+ &iio_dev_attr_hwfifo_enabled.dev_attr.attr,
+ NULL,
+};
+
+static int adxl372_set_watermark(struct iio_dev *indio_dev, unsigned int val)
+{
+ struct adxl372_state *st = iio_priv(indio_dev);
+
+ if (val > ADXL372_FIFO_SIZE)
+ val = ADXL372_FIFO_SIZE;
+
+ st->watermark = val;
+
+ return 0;
+}
+
+static int adxl372_buffer_postenable(struct iio_dev *indio_dev)
+{
+ struct adxl372_state *st = iio_priv(indio_dev);
+ unsigned int mask;
+ int i, ret;
+
+ ret = adxl372_set_interrupts(st, ADXL372_INT1_MAP_FIFO_FULL_MSK, 0);
+ if (ret < 0)
+ return ret;
+
+ mask = *indio_dev->active_scan_mask;
+
+ for (i = 0; i < ARRAY_SIZE(adxl372_axis_lookup_table); i++) {
+ if (mask == adxl372_axis_lookup_table[i].bits)
+ break;
+ }
+
+ if (i == ARRAY_SIZE(adxl372_axis_lookup_table))
+ return -EINVAL;
+
+ st->fifo_format = adxl372_axis_lookup_table[i].fifo_format;
+ st->fifo_set_size = bitmap_weight(indio_dev->active_scan_mask,
+ indio_dev->masklength);
+ /*
+ * The 512 FIFO samples can be allotted in several ways, such as:
+ * 170 sample sets of concurrent 3-axis data
+ * 256 sample sets of concurrent 2-axis data (user selectable)
+ * 512 sample sets of single-axis data
+ */
+ if ((st->watermark * st->fifo_set_size) > ADXL372_FIFO_SIZE)
+ st->watermark = (ADXL372_FIFO_SIZE / st->fifo_set_size);
+
+ st->fifo_mode = ADXL372_FIFO_STREAMED;
+
+ ret = adxl372_configure_fifo(st);
+ if (ret < 0) {
+ st->fifo_mode = ADXL372_FIFO_BYPASSED;
+ adxl372_set_interrupts(st, 0, 0);
+ return ret;
+ }
+
+ return iio_triggered_buffer_postenable(indio_dev);
+}
+
+static int adxl372_buffer_predisable(struct iio_dev *indio_dev)
+{
+ struct adxl372_state *st = iio_priv(indio_dev);
+ int ret;
+
+ ret = iio_triggered_buffer_predisable(indio_dev);
+ if (ret < 0)
+ return ret;
+
+ adxl372_set_interrupts(st, 0, 0);
+ st->fifo_mode = ADXL372_FIFO_BYPASSED;
+ adxl372_configure_fifo(st);
+
+ return 0;
+}
+
+static const struct iio_buffer_setup_ops adxl372_buffer_ops = {
+ .postenable = adxl372_buffer_postenable,
+ .predisable = adxl372_buffer_predisable,
+};
+
+static int adxl372_dready_trig_set_state(struct iio_trigger *trig,
+ bool state)
+{
+ struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
+ struct adxl372_state *st = iio_priv(indio_dev);
+ unsigned long int mask = 0;
+
+ if (state)
+ mask = ADXL372_INT1_MAP_FIFO_FULL_MSK;
+
+ return adxl372_set_interrupts(st, mask, 0);
+}
+
+static const struct iio_trigger_ops adxl372_trigger_ops = {
+ .set_trigger_state = adxl372_dready_trig_set_state,
+};
+
static const struct iio_info adxl372_info = {
.read_raw = adxl372_read_raw,
.debugfs_reg_access = &adxl372_reg_access,
+ .hwfifo_set_watermark = adxl372_set_watermark,
};
+static bool adxl372_readable_noinc_reg(struct device *dev, unsigned int reg)
+{
+ return (reg == ADXL372_FIFO_DATA);
+}
+
static const struct regmap_config adxl372_spi_regmap_config = {
.reg_bits = 7,
.pad_bits = 1,
.val_bits = 8,
.read_flag_mask = BIT(0),
+ .readable_noinc_reg = adxl372_readable_noinc_reg,
};
static int adxl372_probe(struct spi_device *spi)
indio_dev->channels = adxl372_channels;
indio_dev->num_channels = ARRAY_SIZE(adxl372_channels);
+ indio_dev->available_scan_masks = adxl372_channel_masks;
indio_dev->dev.parent = &spi->dev;
indio_dev->name = spi_get_device_id(spi)->name;
indio_dev->info = &adxl372_info;
- indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_SOFTWARE;
ret = adxl372_setup(st);
if (ret < 0) {
return ret;
}
+ ret = devm_iio_triggered_buffer_setup(&st->spi->dev,
+ indio_dev, NULL,
+ adxl372_trigger_handler,
+ &adxl372_buffer_ops);
+ if (ret < 0)
+ return ret;
+
+ iio_buffer_set_attrs(indio_dev->buffer, adxl372_fifo_attributes);
+
+ if (st->spi->irq) {
+ st->dready_trig = devm_iio_trigger_alloc(&st->spi->dev,
+ "%s-dev%d",
+ indio_dev->name,
+ indio_dev->id);
+ if (st->dready_trig == NULL)
+ return -ENOMEM;
+
+ st->dready_trig->ops = &adxl372_trigger_ops;
+ st->dready_trig->dev.parent = &st->spi->dev;
+ iio_trigger_set_drvdata(st->dready_trig, indio_dev);
+ ret = devm_iio_trigger_register(&st->spi->dev, st->dready_trig);
+ if (ret < 0)
+ return ret;
+
+ indio_dev->trig = iio_trigger_get(st->dready_trig);
+
+ ret = devm_request_threaded_irq(&st->spi->dev, st->spi->irq,
+ iio_trigger_generic_data_rdy_poll,
+ NULL,
+ IRQF_TRIGGER_RISING | IRQF_ONESHOT,
+ indio_dev->name, st->dready_trig);
+ if (ret < 0)
+ return ret;
+ }
+
return devm_iio_device_register(&st->spi->dev, indio_dev);
}