On 2018-03-08 14:54, Michael Nosthoff wrote:
Hi,
Sorry for answering my own mail, but I got a bit further. See below
I have an LPS22 sensor which i used sucessfully with Kernel 4.9. Upon
switching to 4.14 it was not loading properly anymore. This failure
occured:
[ 3.827094] iio iio:device1: DRDY on pdata not valid.
[ 3.832578] st-press-i2c: probe of 0-005c failed with error -22
So I started digging. It started working again when I add this entry
to my devicetree:
st,drdy-int-pin = <1>;
So it seems the default value seems to be not set in 4.14 but was in
4.9
I came to the conclusion that the problem happens in
drivers/iio/pressure/st_pressure_core.c in
st_press_common_probe:
struct st_sensors_platform_data *pdata =
(struct st_sensors_platform_data *)press_data->dev->platform_data;
...
if (!pdata && press_data->sensor_settings->drdy_irq.addr)
pdata = (struct st_sensors_platform_data *)&default_press_pdata;
err = st_sensors_init_sensor(indio_dev,
press_data->dev->platform_data);
If pdata is not set (which is correct in my case) it gets assigned a
default value. But in the call to st_sensors_init_sensor it's still
using the data stored in press_data.
Okay, simple solution would be to pass pdata here as well. But I'm a
bit confused about the commit [1] which introduced this. pdata is not
used anymore in this function, so it seems completely useless to set it
there. And so I don't understand what the commit tries to achieve at
all
besides never using the default data.
Somebody seems also to have noticed in the accel driver. See this commit
[2]
and decided to remove the default initialization completely. Which makes
sense
as this code was not doing anything.
I guess the what the intial commit was trying to achieve was to not
overwrite
the pointer in dev->platform_data which i can imagine might be a problem
when
using it as a module. But maybe forgot to alter the following usage of
the data.
So I would suggest to revert commit [2] and pass pdata to
st_sensors_init_sensor
in both cases (st_pressure and st_accel).
Does this make sense?
[1]
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/drivers/iio/pressure/st_pressure_core.c?id=7383d44b84c94aaca4bf695a6bd8a69f2295ef1a
[2]
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/drivers/iio/accel/st_accel_core.c?id=585ed27d06151f98e39238298f43ee261314ae74
--
Regards,
Michael
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