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/input/touchscreen/ti_am335x_tsc.c b/drivers/input/touchscreen/ti_am335x_tsc.c
index 004f134..dfbb9fe 100644
--- a/drivers/input/touchscreen/ti_am335x_tsc.c
+++ b/drivers/input/touchscreen/ti_am335x_tsc.c
@@ -121,7 +121,7 @@
{
unsigned int config;
int i;
- int end_step;
+ int end_step, first_step, tsc_steps;
u32 stepenable;
config = STEPCONFIG_MODE_HWSYNC |
@@ -140,9 +140,11 @@
break;
}
- /* 1 … coordinate_readouts is for X */
- end_step = ts_dev->coordinate_readouts;
- for (i = 0; i < end_step; i++) {
+ tsc_steps = ts_dev->coordinate_readouts * 2 + 2;
+ first_step = TOTAL_STEPS - tsc_steps;
+ /* Steps 16 to 16-coordinate_readouts is for X */
+ end_step = first_step + tsc_steps;
+ for (i = end_step - ts_dev->coordinate_readouts; i < end_step; i++) {
titsc_writel(ts_dev, REG_STEPCONFIG(i), config);
titsc_writel(ts_dev, REG_STEPDELAY(i), STEPCONFIG_OPENDLY);
}
@@ -164,9 +166,9 @@
break;
}
- /* coordinate_readouts … coordinate_readouts * 2 is for Y */
- end_step = ts_dev->coordinate_readouts * 2;
- for (i = ts_dev->coordinate_readouts; i < end_step; i++) {
+ /* 1 ... coordinate_readouts is for Y */
+ end_step = first_step + ts_dev->coordinate_readouts;
+ for (i = first_step; i < end_step; i++) {
titsc_writel(ts_dev, REG_STEPCONFIG(i), config);
titsc_writel(ts_dev, REG_STEPDELAY(i), STEPCONFIG_OPENDLY);
}
@@ -179,7 +181,7 @@
titsc_writel(ts_dev, REG_CHARGECONFIG, config);
titsc_writel(ts_dev, REG_CHARGEDELAY, CHARGEDLY_OPENDLY);
- /* coordinate_readouts * 2 … coordinate_readouts * 2 + 2 is for Z */
+ /* coordinate_readouts + 1 ... coordinate_readouts + 2 is for Z */
config = STEPCONFIG_MODE_HWSYNC |
STEPCONFIG_AVG_16 | ts_dev->bit_yp |
ts_dev->bit_xn | STEPCONFIG_INM_ADCREFM |
@@ -194,8 +196,11 @@
titsc_writel(ts_dev, REG_STEPDELAY(end_step),
STEPCONFIG_OPENDLY);
- /* The steps1 … end and bit 0 for TS_Charge */
- stepenable = (1 << (end_step + 2)) - 1;
+ /* The steps end ... end - readouts * 2 + 2 and bit 0 for TS_Charge */
+ stepenable = 1;
+ for (i = 0; i < tsc_steps; i++)
+ stepenable |= 1 << (first_step + i + 1);
+
ts_dev->step_mask = stepenable;
am335x_tsc_se_set_cache(ts_dev->mfd_tscadc, ts_dev->step_mask);
}
@@ -209,6 +214,7 @@
unsigned int read, diff;
unsigned int i, channel;
unsigned int creads = ts_dev->coordinate_readouts;
+ unsigned int first_step = TOTAL_STEPS - (creads * 2 + 2);
*z1 = *z2 = 0;
if (fifocount % (creads * 2 + 2))
@@ -226,7 +232,7 @@
channel = (read & 0xf0000) >> 16;
read &= 0xfff;
- if (channel < creads) {
+ if (channel > first_step + creads + 2) {
diff = abs(read - prev_val_x);
if (diff < prev_diff_x) {
prev_diff_x = diff;
@@ -234,19 +240,19 @@
}
prev_val_x = read;
- } else if (channel < creads * 2) {
+ } else if (channel == first_step + creads + 1) {
+ *z1 = read;
+
+ } else if (channel == first_step + creads + 2) {
+ *z2 = read;
+
+ } else if (channel > first_step) {
diff = abs(read - prev_val_y);
if (diff < prev_diff_y) {
prev_diff_y = diff;
*y = read;
}
prev_val_y = read;
-
- } else if (channel < creads * 2 + 1) {
- *z1 = read;
-
- } else if (channel < creads * 2 + 2) {
- *z2 = read;
}
}
}