Hi, On 01/11/2013 01:43 AM, Marek Vasut wrote:
This patch implements support for sampling of a touchscreen into the MXS LRADC driver. The LRADC block allows configuring some of it's channels into special mode where they either output the drive voltage or sample it, allowing it to operate a 4-wire or 5-wire resistive touchscreen. In case the touchscreen mode is enabled, the LRADC slot #7 is reserved for touchscreen only, therefore it is not possible to sample 8 LRADC channels at time, but only 7 channels. The touchscreen controller is configured such that the PENDOWN event disables touchscreen interrupts and triggers execution of worker thread, which then polls the touchscreen controller for X, Y and Pressure values. This reduces the overhead of interrupt-driven operation. Upon the PENUP event, the worker thread re-enables the PENDOWN detection interrupt and exits. Signed-off-by: Marek Vasut <marex@xxxxxxx> Cc: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx> Cc: Fabio Estevam <fabio.estevam@xxxxxxxxxxxxx> Cc: Jonathan Cameron <jic23@xxxxxxxxxx> Cc: Shawn Guo <shawn.guo@xxxxxxxxxx> --- .../bindings/staging/iio/adc/mxs-lradc.txt | 6 + drivers/staging/iio/adc/mxs-lradc.c | 473 +++++++++++++++++++- 2 files changed, 455 insertions(+), 24 deletions(-)
Works fine with apx4devkit. Tested-by: Lauri Hintsala <lauri.hintsala@xxxxxxxxxxxx> Best Regards, Lauri Hintsala -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
