On 11/05/2019 13.37, Jonathan Cameron wrote:
On Tue, 7 May 2019 10:02:25 +0200
Sean Nyekjaer <sean@xxxxxxxxxx> wrote:
This adds support for using iio triggers, this is needed because
our hardware guys forgot to connect the irq pins from imu device
to the SoC.
Signed-off-by: Sean Nyekjaer <sean@xxxxxxxxxx>
Hi Sean
A small question on the size of the buffer needed inline. Otherwise looks
good to me.
---
drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c | 37 ++++++++++++++++++++
1 file changed, 37 insertions(+)
diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
index 1ca69598678f..65ab853202de 100644
--- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
+++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
@@ -40,8 +40,11 @@
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/delay.h>
+#include <linux/iio/buffer.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
#include <linux/pm.h>
#include <linux/regmap.h>
#include <linux/bitfield.h>
@@ -945,6 +948,30 @@ static int st_lsm6dsx_init_hw_timer(struct st_lsm6dsx_hw *hw)
return 0;
}
+static irqreturn_t st_lsm6dsx_trigger_handler(int irq, void *p)
+{
+ struct iio_poll_func *pf = p;
+ struct iio_dev *indio_dev = pf->indio_dev;
+ struct st_lsm6dsx_sensor *sensor = iio_priv(indio_dev);
+ u16 buffer[4 * sizeof(s64)/sizeof(u16)];
The size may well be correct, but that particular way of expressing it doesn't make
it terribly clear.
It seems a bit large... You need the space for the timestamp, so it needs to be
padded to a u64, but that would still require your other channels to need
more than 2*sizeof(s64)/sizeof(u16) u16s which is 9 or more of them.
Right now we have u16[16], so that quite at bit large :-)
So maybe something like:
/* 3x s16 + 1x s16(padding) + 1x s64 timestamp */
u16 buffer[2 * sizeof(s64)/sizeof(u16)];
Would do it?
+ int tmp, bit;
+
+ memset(buffer, 0, sizeof(buffer));
+
+ for_each_set_bit(bit, indio_dev->active_scan_mask, indio_dev->masklength) {
+ st_lsm6dsx_read_oneshot(sensor,
+ indio_dev->channels[bit].address, &tmp);
+ buffer[bit] = tmp;
+ }
As you pointed out in the
"[PATCH 1/2] iio: adc: ti-ads8688: save values correct in buffer"
When taking this approach it will not shift down.
+
+ iio_push_to_buffers_with_timestamp(indio_dev, buffer,
+ iio_get_time_ns(indio_dev));
+
+ iio_trigger_notify_done(indio_dev->trig);
+
+ return IRQ_HANDLED;
+}
+
static int st_lsm6dsx_init_device(struct st_lsm6dsx_hw *hw)
{
u8 drdy_int_reg;
@@ -1093,6 +1120,16 @@ int st_lsm6dsx_probe(struct device *dev, int irq, int hw_id, const char *name,
err = st_lsm6dsx_fifo_setup(hw);
if (err < 0)
return err;
+ } else {
+ for (i = 0; i < ST_LSM6DSX_ID_MAX; i++) {
+ err = devm_iio_triggered_buffer_setup(hw->dev,
+ hw->iio_devs[i], NULL,
+ st_lsm6dsx_trigger_handler, NULL);
+ if (err < 0) {
+ dev_err(hw->dev, "iio triggered buffer setup failed\n");
+ return err;
+ }
+ }
}
for (i = 0; i < ST_LSM6DSX_ID_MAX; i++) {
