lkml.org 
[lkml]   [2020]   [Mar]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH v3 1/4] iio: accel: adxl372: Add support for FIFO peak mode
From
Date
On 3/18/20 12:09 PM, Alexandru Tachici wrote:
> From: Stefan Popa <stefan.popa@analog.com>
>
> By default, if all three channels (x, y, z) are enabled, sample sets of
> concurrent 3-axis data is stored in the FIFO. This patch adds the option
> to configure the FIFO to store peak acceleration (x, y and z) of every
> over-threshold event. When pushing to iio buffer we push only enabled
> axis data.
>
> Signed-off-by: Stefan Popa <stefan.popa@analog.com>
> ---
> drivers/iio/accel/adxl372.c | 74 ++++++++++++++++++++++++++++++++++++-
> 1 file changed, 73 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/iio/accel/adxl372.c b/drivers/iio/accel/adxl372.c
> index 67b8817995c0..90c37d6f10d3 100644
> --- a/drivers/iio/accel/adxl372.c
> +++ b/drivers/iio/accel/adxl372.c
> @@ -133,6 +133,9 @@
>
> /* The ADXL372 includes a deep, 512 sample FIFO buffer */
> #define ADXL372_FIFO_SIZE 512
> +#define ADXL372_X_AXIS_EN(x) (((x) >> 0) & 0x1)
> +#define ADXL372_Y_AXIS_EN(x) (((x) >> 1) & 0x1)
> +#define ADXL372_Z_AXIS_EN(x) (((x) >> 2) & 0x1)
>
> /*
> * At +/- 200g with 12-bit resolution, scale is computed as:
> @@ -253,6 +256,7 @@ struct adxl372_state {
> struct iio_trigger *dready_trig;
> enum adxl372_fifo_mode fifo_mode;
> enum adxl372_fifo_format fifo_format;
> + unsigned int fifo_axis_mask;
> enum adxl372_op_mode op_mode;
> enum adxl372_act_proc_mode act_proc_mode;
> enum adxl372_odr odr;
> @@ -264,6 +268,7 @@ struct adxl372_state {
> u8 int2_bitmask;
> u16 watermark;
> __be16 fifo_buf[ADXL372_FIFO_SIZE];
> + bool peak_fifo_mode_en;
> };
>
> static const unsigned long adxl372_channel_masks[] = {
> @@ -522,6 +527,22 @@ static int adxl372_get_status(struct adxl372_state *st,
> return ret;
> }
>
> +static void adxl372_arrange_axis_data(struct adxl372_state *st, __be16 *sample)
> +{
> + __be16 axis_sample[3];
> + int i = 0;
> +
> + memset(axis_sample, 0, 3 * sizeof(__be16));
> + if (ADXL372_X_AXIS_EN(st->fifo_axis_mask))
> + axis_sample[i++] = sample[0];
> + if (ADXL372_Y_AXIS_EN(st->fifo_axis_mask))
> + axis_sample[i++] = sample[1];
> + if (ADXL372_Z_AXIS_EN(st->fifo_axis_mask))
> + axis_sample[i++] = sample[2];
> +
> + memcpy(sample, axis_sample, 3 * sizeof(__be16));
> +}
> +
> static irqreturn_t adxl372_trigger_handler(int irq, void *p)
> {
> struct iio_poll_func *pf = p;
> @@ -553,8 +574,12 @@ static irqreturn_t adxl372_trigger_handler(int irq, void *p)
> goto err;
>
> /* Each sample is 2 bytes */
> - for (i = 0; i < fifo_entries; i += st->fifo_set_size)
> + for (i = 0; i < fifo_entries; i += st->fifo_set_size) {
> + /* filter peak detection data */
> + if (st->peak_fifo_mode_en)
> + adxl372_arrange_axis_data(st, &st->fifo_buf[i]);
> iio_push_to_buffers(indio_dev, &st->fifo_buf[i]);
> + }
> }
> err:
> iio_trigger_notify_done(indio_dev->trig);
> @@ -722,6 +747,43 @@ static int adxl372_write_raw(struct iio_dev *indio_dev,
> }
> }
>
> +static ssize_t adxl372_peak_fifo_en_get(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + struct adxl372_state *st = iio_priv(dev_to_iio_dev(dev));
> +
> + return sprintf(buf, "%d\n", st->peak_fifo_mode_en);
> +}
> +
> +static ssize_t adxl372_peak_fifo_en_set(struct device *dev,
> + struct device_attribute *attr,
> + const char *buf, size_t len)
> +{
> + struct iio_dev *indio_dev = dev_to_iio_dev(dev);
> + struct adxl372_state *st = iio_priv(indio_dev);
> + bool val;
> + int ret;
> +
> + ret = iio_device_claim_direct_mode(indio_dev);
> + if (ret < 0)
> + return ret;
> +
> + ret = kstrtobool(buf, &val);
> + if (ret)
> + return ret;
> +
> + st->peak_fifo_mode_en = val;
> +
> + iio_device_release_direct_mode(indio_dev);
> +
> + return len;
> +}
> +
> +static IIO_DEVICE_ATTR(hwfifo_peak_mode_enable, 0644,
> + adxl372_peak_fifo_en_get,
> + adxl372_peak_fifo_en_set, 0);
> +

Rather than going with a non-standard attribute, I'd register a IIO
trigger for the peak mode and switch between peak and normal mode by
assigning the corresponding trigger.

At least that's how I understand how this mode works. Data capture is
triggered by exceeding a threshold.

- Lars

\
 
 \ /
  Last update: 2020-03-18 11:11    [W:0.045 / U:0.564 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site