On Wed, Jan 23, 2019 at 11:25:59PM +0530, Bharath Vedartham wrote: > I am trying to add the 3-axis compass data channels to the > simple_dummy_channel. I have mounted configfs and am able to load the > modules correctly. Is this the right approach? printk is not printing > anything to syslogs. > > This is part of the iio_tasks in (I have finished the first 2 tasks): > > https://kernelnewbies.org/IIO_tasks > > output of lsmod | grep dummy: > > iio_dummy 20480 2 > iio_dummy_evgen 16384 1 iio_dummy > > output of ls /sys/bus/iio/devices/iio:device0/: > > buffer in_sampling_frequency > in_voltage-voltage_scale > current_timestamp_clock in_steps_calibheight name > dev in_steps_en out_voltage0_raw > events in_steps_input power > in_accel_x_calibbias in_voltage0_offset scan_elements > in_accel_x_calibscale in_voltage0_raw subsystem > in_accel_x_raw in_voltage0_scale trigger > in_activity_running_input in_voltage1-voltage2_raw uevent > in_activity_walking_input in_voltage3-voltage4_raw > > I have also put the diff.Added channel to iio_dummy_channels and added > element to enum simple_dummy_scan_elements. > > Thank you, > Bharath > > --- > drivers/iio/dummy/iio_simple_dummy.c | 43 ++++++++++++++++++++++++++++++++++++ > drivers/iio/dummy/iio_simple_dummy.h | 3 +++ > 2 files changed, 46 insertions(+) > > diff --git a/drivers/iio/dummy/iio_simple_dummy.c b/drivers/iio/dummy/iio_simple_dummy.c > index 6205247..306e0cd 100644 > --- a/drivers/iio/dummy/iio_simple_dummy.c > +++ b/drivers/iio/dummy/iio_simple_dummy.c > @@ -268,6 +268,48 @@ static const struct iio_chan_spec iio_dummy_channels[] = { > .num_event_specs = 1, > #endif /* CONFIG_IIO_SIMPLE_DUMMY_EVENTS */ > }, > + { > + .type = IIO_MAGN, > + .modified = 1, > + .channel2 = IIO_MOD_X, > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), > + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), > + .scan_index = DUMMY_INDEX_MAGNX, > + .scan_type = { > + .sign = 'u', > + .realbits = 16, > + .storagebits = 16, > + .shift = 0, > + }, > + }, > + { > + .type = IIO_MAGN, > + .modified = 1, > + .channel2 = IIO_MOD_Y, > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), > + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), > + .scan_index = DUMMY_INDEX_MAGNY, > + .scan_type = { > + .sign = 'u', > + .realbits= 16, > + .storagebits = 16, > + .shift = 0, > + }, > + }, > + { > + .type = IIO_MAGN, > + .modified = 1, > + .channel2 = IIO_MOD_Z, > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), > + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), > + .scan_index = DUMMY_INDEX_MAGNZ, > + .scan_type = { > + .sign = 'u', > + .realbits = 16, > + .storagebits = 16, > + .shift = 0, > + }, > + }, > }; > > /** > @@ -621,6 +663,7 @@ static struct iio_sw_device *iio_dummy_probe(const char *name) > /* Provide description of available channels */ > indio_dev->channels = iio_dummy_channels; > indio_dev->num_channels = ARRAY_SIZE(iio_dummy_channels); > + printk(KERN_DEBUG "No of channels are %d\n",indio_dev -> num_channels); > > /* > * Provide device type specific interface functions and > diff --git a/drivers/iio/dummy/iio_simple_dummy.h b/drivers/iio/dummy/iio_simple_dummy.h > index f7005c3..be6eff0 100644 > --- a/drivers/iio/dummy/iio_simple_dummy.h > +++ b/drivers/iio/dummy/iio_simple_dummy.h > @@ -110,6 +110,9 @@ enum iio_simple_dummy_scan_elements { > DUMMY_INDEX_DIFFVOLTAGE_1M2, > DUMMY_INDEX_DIFFVOLTAGE_3M4, > DUMMY_INDEX_ACCELX, > + DUMMY_INDEX_MAGNX, > + DUMMY_INDEX_MAGNY, > + DUMMY_INDEX_MAGNZ, > }; This looks good. But think about what would happen if you read one of those attributes ? Like if you do: # cat in_accel_x_raw 34 (Looking at hardcoded value in the dummy source) st->accel_val = 34; -- Himanshu Jha Undergraduate Student Department of Electronics & Communication Guru Tegh Bahadur Institute of Technology _______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies