From: Brad Griffis <bgrif...@ti.com> 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 <bgrif...@ti.com> [vigne...@ti.com: Ported the patch from v3.12 to v3.18rc2] Signed-off-by: Vignesh R <vigne...@ti.com> Acked-by: Jonathan Cameron <ji...@kernel.org> --- drivers/iio/adc/ti_am335x_adc.c | 5 ++-- drivers/input/touchscreen/ti_am335x_tsc.c | 42 ++++++++++++++++++------------- 2 files changed, 26 insertions(+), 21 deletions(-) diff --git a/drivers/iio/adc/ti_am335x_adc.c b/drivers/iio/adc/ti_am335x_adc.c index b730864731e8..adba23246474 100644 --- a/drivers/iio/adc/ti_am335x_adc.c +++ b/drivers/iio/adc/ti_am335x_adc.c @@ -86,19 +86,18 @@ static void tiadc_step_config(struct iio_dev *indio_dev) { 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; diff --git a/drivers/input/touchscreen/ti_am335x_tsc.c b/drivers/input/touchscreen/ti_am335x_tsc.c index 2ce649520fe0..1aeac9675fe7 100644 --- a/drivers/input/touchscreen/ti_am335x_tsc.c +++ b/drivers/input/touchscreen/ti_am335x_tsc.c @@ -121,7 +121,7 @@ static void titsc_step_config(struct titsc *ts_dev) { 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 @@ static void titsc_step_config(struct titsc *ts_dev) 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 @@ static void titsc_step_config(struct titsc *ts_dev) 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 @@ static void titsc_step_config(struct titsc *ts_dev) 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 @@ static void titsc_step_config(struct titsc *ts_dev) 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 @@ static void titsc_read_coordinates(struct titsc *ts_dev, 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 @@ static void titsc_read_coordinates(struct titsc *ts_dev, 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 @@ static void titsc_read_coordinates(struct titsc *ts_dev, } 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; } } } -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html