From: Jonathan Cameron <jic23@kernel.org>
To: Lorenzo Bianconi <lorenzo@kernel.org>
Cc: lorenzo.bianconi@redhat.com, mario.tesi@st.com,
linux-iio@vger.kernel.org
Subject: Re: [PATCH] iio: imu: st_lsm6dsx: fix decimation factor estimation
Date: Sun, 1 Dec 2019 20:56:21 +0000 [thread overview]
Message-ID: <20191201205621.7d396b62@archlinux> (raw)
In-Reply-To: <6d08e5a80bb0c49eb96dc883ff1ed2936f142bbb.1574956387.git.lorenzo@kernel.org>
On Thu, 28 Nov 2019 17:55:18 +0200
Lorenzo Bianconi <lorenzo@kernel.org> wrote:
> Fix decimation factor and sip estimation for LSM6DSM series
> (max value for decimation factor is 32).
> If gyro and accel sensors are enabled at 12.5Hz and 416Hz
> respectively, decimation factor lookup will fail, producing
> unaligned data.
I'll confess I don't really follow how those values make sense
(as opposed to 13Hz) but I'm sure they do :)
> Remove unused decimator filed in st_lsm6dsx_sensor structure.
>
> Fixes: f8710f0357bc ("iio: imu: st_lsm6dsx: express odr in mHZ")
> Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Applied to the fixes-togreg branch of iio.git.
Thanks,
Jonathan
> ---
> drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h | 2 --
> .../iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c | 25 +++++++++++++------
> 2 files changed, 18 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h
> index b54aefcdaad4..dc55d7dff3eb 100644
> --- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h
> +++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h
> @@ -320,7 +320,6 @@ enum st_lsm6dsx_fifo_mode {
> * @odr: Output data rate of the sensor [Hz].
> * @watermark: Sensor watermark level.
> * @sip: Number of samples in a given pattern.
> - * @decimator: FIFO decimation factor.
> * @ts_ref: Sensor timestamp reference for hw one.
> * @ext_info: Sensor settings if it is connected to i2c controller
> */
> @@ -334,7 +333,6 @@ struct st_lsm6dsx_sensor {
>
> u16 watermark;
> u8 sip;
> - u8 decimator;
> s64 ts_ref;
>
> struct {
> diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c
> index bfd4c6306c0b..cb536b81a1c2 100644
> --- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c
> +++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c
> @@ -78,14 +78,20 @@ struct st_lsm6dsx_decimator_entry st_lsm6dsx_decimator_table[] = {
> { 32, 0x7 },
> };
>
> -static int st_lsm6dsx_get_decimator_val(u8 val)
> +static int
> +st_lsm6dsx_get_decimator_val(struct st_lsm6dsx_sensor *sensor, u32 max_odr)
> {
> const int max_size = ARRAY_SIZE(st_lsm6dsx_decimator_table);
> + u32 decimator = max_odr / sensor->odr;
> int i;
>
> - for (i = 0; i < max_size; i++)
> - if (st_lsm6dsx_decimator_table[i].decimator == val)
> + if (decimator > 1)
> + decimator = round_down(decimator, 2);
> +
> + for (i = 0; i < max_size; i++) {
> + if (st_lsm6dsx_decimator_table[i].decimator == decimator)
> break;
> + }
>
> return i == max_size ? 0 : st_lsm6dsx_decimator_table[i].val;
> }
> @@ -111,6 +117,13 @@ static void st_lsm6dsx_get_max_min_odr(struct st_lsm6dsx_hw *hw,
> }
> }
>
> +static u8 st_lsm6dsx_get_sip(struct st_lsm6dsx_sensor *sensor, u32 min_odr)
> +{
> + u8 sip = sensor->odr / min_odr;
> +
> + return sip > 1 ? round_down(sip, 2) : sip;
> +}
> +
> static int st_lsm6dsx_update_decimators(struct st_lsm6dsx_hw *hw)
> {
> const struct st_lsm6dsx_reg *ts_dec_reg;
> @@ -131,12 +144,10 @@ static int st_lsm6dsx_update_decimators(struct st_lsm6dsx_hw *hw)
> sensor = iio_priv(hw->iio_devs[i]);
> /* update fifo decimators and sample in pattern */
> if (hw->enable_mask & BIT(sensor->id)) {
> - sensor->sip = sensor->odr / min_odr;
> - sensor->decimator = max_odr / sensor->odr;
> - data = st_lsm6dsx_get_decimator_val(sensor->decimator);
> + sensor->sip = st_lsm6dsx_get_sip(sensor, min_odr);
> + data = st_lsm6dsx_get_decimator_val(sensor, max_odr);
> } else {
> sensor->sip = 0;
> - sensor->decimator = 0;
> data = 0;
> }
> ts_sip = max_t(u16, ts_sip, sensor->sip);
prev parent reply other threads:[~2019-12-01 20:56 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-11-28 15:55 [PATCH] iio: imu: st_lsm6dsx: fix decimation factor estimation Lorenzo Bianconi
2019-12-01 20:56 ` Jonathan Cameron [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20191201205621.7d396b62@archlinux \
--to=jic23@kernel.org \
--cc=linux-iio@vger.kernel.org \
--cc=lorenzo.bianconi@redhat.com \
--cc=lorenzo@kernel.org \
--cc=mario.tesi@st.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).