>
> On Sun, 1 Mar 2020 20:28:03 +0100
> Lorenzo Bianconi <lorenzo@xxxxxxxxxx> wrote:
>
> > Disable MIPI I3C during device reset in order to avoid
> > possible races on interrupt line 1. If the first interrupt
> > line is asserted during hw reset the device will work in
> > I3C-only mode
> >
> > Reported-by: Mario Tesi <mario.tesi@xxxxxx>
> > Signed-off-by: Lorenzo Bianconi <lorenzo@xxxxxxxxxx>
>
> Fixes tag?
Hi Jonathan,
I am not sure since Mario just reported me this issue can occur.
Maybe this one:
2660b0080bb2 ("iio: imu: st_lsm6dsx: add i3c basic support for LSM6DSO
and LSM6DSR")
>
> One trivial thing inline.
>
ack, I will fix it (I am use to network comment syntax now :))
> Is this something we should be looking to have applied to stable?
>
Not sure.
@Vitor: have you ever faced the issue?
Regards,
Lorenzo
> Jonathan
>
> > ---
> > I have not been able to test this patch on a I3C device, just SPI/I2C
> > ---
> > drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h | 2 ++
> > drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c | 30 ++++++++++++++++++++
> > 2 files changed, 32 insertions(+)
> >
> > diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h
> > index f2113a63721a..dfcbe7c42493 100644
> > --- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h
> > +++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h
> > @@ -266,6 +266,7 @@ struct st_lsm6dsx_ext_dev_settings {
> > * @wai: Sensor WhoAmI default value.
> > * @reset: register address for reset.
> > * @boot: register address for boot.
> > + * @i3c_disable: register address for enabling/disabling I3C (addr + mask).
> > * @bdu: register address for Block Data Update.
> > * @max_fifo_size: Sensor max fifo length in FIFO words.
> > * @id: List of hw id/device name supported by the driver configuration.
> > @@ -284,6 +285,7 @@ struct st_lsm6dsx_settings {
> > u8 wai;
> > struct st_lsm6dsx_reg reset;
> > struct st_lsm6dsx_reg boot;
> > + struct st_lsm6dsx_reg i3c_disable;
> > struct st_lsm6dsx_reg bdu;
> > u16 max_fifo_size;
> > struct {
> > diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
> > index 84d219ae6aee..b1435c5d2d6d 100644
> > --- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
> > +++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
> > @@ -751,6 +751,10 @@ static const struct st_lsm6dsx_settings st_lsm6dsx_sensor_settings[] = {
> > .addr = 0x12,
> > .mask = BIT(7),
> > },
> > + .i3c_disable = {
> > + .addr = 0x18,
> > + .mask = BIT(1),
> > + },
> > .bdu = {
> > .addr = 0x12,
> > .mask = BIT(6),
> > @@ -1128,6 +1132,10 @@ static const struct st_lsm6dsx_settings st_lsm6dsx_sensor_settings[] = {
> > .addr = 0x12,
> > .mask = BIT(7),
> > },
> > + .i3c_disable = {
> > + .addr = 0x18,
> > + .mask = BIT(1),
> > + },
> > .bdu = {
> > .addr = 0x12,
> > .mask = BIT(6),
> > @@ -2041,6 +2049,19 @@ static int st_lsm6dsx_init_device(struct st_lsm6dsx_hw *hw)
> > const struct st_lsm6dsx_reg *reg;
> > int err;
> >
> > + /* disable MIPI I3C during device reset in order to avoid
>
> comment syntax
> /*
> * disable...
>
> > + * possible races on interrupt line 1. If the first interrupt
> > + * line is asserted during hw reset the device will work in
> > + * I3C-only mode
> > + */
> > + if (hw->settings->i3c_disable.addr) {
> > + reg = &hw->settings->i3c_disable;
> > + err = regmap_update_bits(hw->regmap, reg->addr, reg->mask,
> > + ST_LSM6DSX_SHIFT_VAL(1, reg->mask));
> > + if (err < 0)
> > + return err;
> > + }
> > +
> > /* device sw reset */
> > reg = &hw->settings->reset;
> > err = regmap_update_bits(hw->regmap, reg->addr, reg->mask,
> > @@ -2059,6 +2080,15 @@ static int st_lsm6dsx_init_device(struct st_lsm6dsx_hw *hw)
> >
> > msleep(50);
> >
> > + /* enable MIPI I3C */
> > + if (hw->settings->i3c_disable.addr) {
> > + reg = &hw->settings->i3c_disable;
> > + err = regmap_update_bits(hw->regmap, reg->addr, reg->mask,
> > + ST_LSM6DSX_SHIFT_VAL(0, reg->mask));
> > + if (err < 0)
> > + return err;
> > + }
> > +
> > /* enable Block Data Update */
> > reg = &hw->settings->bdu;
> > err = regmap_update_bits(hw->regmap, reg->addr, reg->mask,
>
