6 Commits

Author SHA1 Message Date
Oleksij Rempel
b617693a5d iio: adc: tsc2046: add .read_raw support
Add read_raw() support to make use of iio_hwmon and other iio clients.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Link: https://lore.kernel.org/r/20220117082852.3370869-1-o.rempel@pengutronix.de
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2022-01-23 18:03:37 +00:00
Oleksij Rempel
84e5d88953 iio: adc: tsc2046: rework the trigger state machine
Initially this was designed to:
| Fix sleeping in atomic context warning and a deadlock after iio_trigger_poll()
| call
|
| If iio_trigger_poll() is called after IRQ was disabled, we will call
| reenable_trigger() directly from hard IRQ or hrtimer context instead of
| IRQ thread. In this case we will run in to multiple issue as sleeping in atomic
| context and a deadlock.
|
| To avoid this issue, rework the trigger to use state machine. All state
| changes are done over the hrtimer, so it allows us to drop fsleep() and
| avoid the deadlock.

Since this issue was fixed by: 9020ef659885 ("iio: trigger: Fix a scheduling
whilst atomic issue seen on tsc2046"). This patch is a cleanup to make
state machine easier to follow.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Link: https://lore.kernel.org/r/20220111130402.3404769-1-o.rempel@pengutronix.de
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2022-01-23 18:03:36 +00:00
Oleksij Rempel
69b31fd7a6 iio: adc: tsc2046: fix scan interval warning
Sync if statement with the actual warning.

Fixes: 9504db5765e8 ("iio: adc: tsc2046: fix a warning message in tsc2046_adc_update_scan_mode()")
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Link: https://lore.kernel.org/r/20211007093007.1466-2-o.rempel@pengutronix.de
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2021-10-17 17:23:17 +01:00
Alexandru Ardelean
49bd77560f iio: adc: remove unused private data assigned with spi_set_drvdata()
These were usually used before the conversion to devm_ functions, so that
the remove hook would be able to retrieve the pointer and do cleanups on
remove.
When the conversion happened, they should have been removed, but were
omitted.

Some drivers were copied from drivers that fit the criteria described
above. In any case, in order to prevent more drivers from being used as
example (and have spi_set_drvdata() needlessly set), this change removes it
from the IIO ADC group.

Signed-off-by: Alexandru Ardelean <aardelean@deviqon.com>
Link: https://lore.kernel.org/r/20210513111035.77950-1-aardelean@deviqon.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2021-06-13 17:00:17 +01:00
Dan Carpenter
9504db5765 iio: adc: tsc2046: fix a warning message in tsc2046_adc_update_scan_mode()
These variables are unsigned so the condition can't be less than zero
and the warning message will never be printed.

Fixes: 9374e8f5a38d ("iio: adc: add ADC driver for the TI TSC2046 controller")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/YJ+ZuO43TnguY5vq@mwanda
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2021-06-03 18:24:12 +01:00
Oleksij Rempel
9374e8f5a3 iio: adc: add ADC driver for the TI TSC2046 controller
Basically the TI TSC2046 touchscreen controller is 8 channel ADC optimized for
the touchscreen use case. By implementing it as an IIO ADC device, we can
make use of resistive-adc-touch and iio-hwmon drivers.

Polled readings are currently not implemented to keep this patch small, so
iio-hwmon will not work out of the box for now.

So far, this driver was tested with a custom version of resistive-adc-touch driver,
since it needs to be extended to make use of Z1 and Z2 channels. The X/Y
are working without additional changes.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20210428073208.19570-4-o.rempel@pengutronix.de
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2021-05-17 13:49:11 +01:00