Input: ti_am335x_tsc - interchange touchscreen and ADC steps
This patch makes the initial changes required to workaround TSC-false
pen-up interrupts. It is required to implement these changes in order to
remove udelay in the TSC interrupt handler and false pen-up events. The
charge step is to be executed immediately after sampling X+. Hence TSC is
made to use higher numbered steps (steps 5 to 16 for 5 co-ordinate
readouts, 4 wire TSC configuration) and ADC to use lower ones. Further X
co-ordinate readouts must be the last to be sampled, thus co-ordinates are
sampled in the order Y-Z-X.
Signed-off-by: Brad Griffis <bgriffis@ti.com>
[vigneshr@ti.com: Ported the patch from v3.12 to v3.19rc1]
Signed-off-by: Vignesh R <vigneshr@ti.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
diff --git a/drivers/iio/adc/ti_am335x_adc.c b/drivers/iio/adc/ti_am335x_adc.c
index b730864..adba232 100644
--- a/drivers/iio/adc/ti_am335x_adc.c
+++ b/drivers/iio/adc/ti_am335x_adc.c
@@ -86,19 +86,18 @@
{
struct tiadc_device *adc_dev = iio_priv(indio_dev);
unsigned int stepconfig;
- int i, steps;
+ int i, steps = 0;
/*
* There are 16 configurable steps and 8 analog input
* lines available which are shared between Touchscreen and ADC.
*
- * Steps backwards i.e. from 16 towards 0 are used by ADC
+ * Steps forwards i.e. from 0 towards 16 are used by ADC
* depending on number of input lines needed.
* Channel would represent which analog input
* needs to be given to ADC to digitalize data.
*/
- steps = TOTAL_STEPS - adc_dev->channels;
if (iio_buffer_enabled(indio_dev))
stepconfig = STEPCONFIG_AVG_16 | STEPCONFIG_FIFO1
| STEPCONFIG_MODE_SWCNT;