On Thu, Dec 17, 2015 at 5:16 PM, Srinivas Pandruvada <srinivas.pandruvada@xxxxxxxxxxxxxxx> wrote: > On Thu, 2015-12-17 at 17:07 -0800, Nish Aravamudan wrote: >> On Thu, Dec 17, 2015 at 4:51 PM, Srinivas Pandruvada >> <srinivas.pandruvada@xxxxxxxxxxxxxxx> wrote: >> > On Thu, 2015-12-17 at 15:38 -0800, Nish Aravamudan wrote: >> > > [Starting a new thread from https://lkml.org/lkml/2015/12/15/663, >> > > as >> > > now my laptop is displaying values in the sysfs *raw* files.] >> > > >> > > So I'm trying to understand exactly how the hid-sensor-accel-3d >> > > driver works. >> > > >> > > If I turn up debugging, when I `cat >> > > /sys/bus/iio/devices/device*/*raw*`, I see "iio iio:device3: >> > > accel_3d_proc_event" and I think that means that >> > > hid_sensor_push_data() is getting called. >> > > >> > > But read()'s on /dev/iio:device3 never produces anything, which >> > > is >> > > what iio-sensor-proxy uses to translate events to dbus. >> > > >> > > Is it expected that the dev-node is "silent"? Just trying to >> > > understand if an extension to the driver to support a chardev >> > > based >> > > output is appropriate, or if iio-sensor-proxy needs to be changed >> > > to >> > > handle this device. >> > >> > You are saying there is some regression. This used to work and now >> > it >> > doesn't work. Is raw values are displayed correctly, when you do >> > "cat"? >> > If cat of raw values is working then power on of sensors is >> > working. >> >> Sorry, I was unclear. I don't know if this is a regression. I can try >> going back to an older kernel to see if the /dev/iio:device* files >> produced any output. >> >> Yes, the *raw* files in sysfs are producing output, that is changing >> as I move the laptop around. But the /dev/ nodes seem to produce no >> output (I'm still reading through the driver code to understand where >> that data should be coming from. >> >> > Turn on HID debug prints. If it is regression we can do git bisect. >> > Any ACPI or PM changes can break this. Usually there will be GPIOs >> > which will be involved in power on, where ACPI comes into play. >> > This >> > will be done by i2c-hid. There are some prints in i2c-hid which can >> > be >> > enabled also. >> >> Ok, I will try this, as well. >> > > Try increasing in_accel_sampling_frequency > echo 100 > in_accel_sampling_frequency > Adjust hysteresis to a low value > echo 0 > in_accel_hysteresis > These values are very vendor specific. Adjusting the values in this way didn't seem to make any difference. Also, `cat in_accel_hysteresis` gave EINVAL, but I was able to echo 0 to it. -Nish -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
