Re: [PATCH v2 4/4] iio: accel: adxl345: Add support for triggered buffer

From: Andy Shevchenko
Date: Mon May 01 2017 - 07:24:42 EST


On Sat, Apr 29, 2017 at 10:49 AM, Eva Rachel Retuya <eraretuya@xxxxxxxxx> wrote:
> Previously, the only way to capture data is to read the exposed sysfs
> files in_accel_[x/y/z]_raw and applying the scale from in_accel_scale.
> Provide a way for continuous data capture that allows multiple data
> channels to be read at once by setting up buffer support.
>
> Initialize scan_type fields that describe the buffer and make sure to
> claim and release direct mode in read_raw. The latter is done to ensure
> no raw reads are attempted when utilizing the buffer and vice versa.
>
> Lastly, add triggered buffer support that allows utilization of any
> given trigger such as DATA_READY, hrtimer, etc. to initiate capturing of
> data and placing said data in the buffer. The trigger handler performs
> an all-axes read with timestamp.

One nit below.
FWIW:
Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>

> +static irqreturn_t adxl345_trigger_handler(int irq, void *p)
> +{
> + struct iio_poll_func *pf = p;
> + struct iio_dev *indio_dev = pf->indio_dev;
> + struct adxl345_data *data = iio_priv(indio_dev);
> + int ret;
> +
> + mutex_lock(&data->lock);
> + /* Make sure data is ready when using external trigger */
> + if (!data->data_ready_trig_on) {
> + ret = adxl345_data_ready(data);
> + if (ret < 0)
> + goto error;
> + }
> +
> + ret = regmap_bulk_read(data->regmap, ADXL345_REG_DATAX0, data->buffer,
> + sizeof(__le16) * 3);
> + if (ret < 0)
> + goto error;
> +
> + iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
> + pf->timestamp);

> +error:

I would call it 'err_unlock_notify'.

> + mutex_unlock(&data->lock);
> + iio_trigger_notify_done(indio_dev->trig);
> +
> + return IRQ_HANDLED;
> +}

--
With Best Regards,
Andy Shevchenko