Input: ucb1400_ts - enable ADC Filter

This patch enables ADC filtering on UCB1400 codec by default. The
benefit from this change is mostly on some Colibri boards where
the ADCSYNC pin of the UCB1400 codec isn't connected causing the
touchscreen to jitter very badly. This change has no visible
effect on boards where the ADCSYNC pin is connected.

Signed-off-by: Marek Vasut <marek.vasut@gmail.com>
Tested-by: Palo Revak <palo@bielyvlk.sk>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
This commit is contained in:
Marek Vasut 2009-08-20 22:05:53 -07:00 committed by Dmitry Torokhov
parent 3b7307c2d6
commit 1700f5fde8
2 changed files with 13 additions and 0 deletions

View File

@ -345,6 +345,7 @@ static int ucb1400_ts_detect_irq(struct ucb1400_ts *ucb)
static int ucb1400_ts_probe(struct platform_device *dev)
{
int error, x_res, y_res;
u16 fcsr;
struct ucb1400_ts *ucb = dev->dev.platform_data;
ucb->ts_idev = input_allocate_device();
@ -382,6 +383,14 @@ static int ucb1400_ts_probe(struct platform_device *dev)
ucb->ts_idev->evbit[0] = BIT_MASK(EV_ABS) | BIT_MASK(EV_KEY);
ucb->ts_idev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
/*
* Enable ADC filter to prevent horrible jitter on Colibri.
* This also further reduces jitter on boards where ADCSYNC
* pin is connected.
*/
fcsr = ucb1400_reg_read(ucb->ac97, UCB_FCSR);
ucb1400_reg_write(ucb->ac97, UCB_FCSR, fcsr | UCB_FCSR_AVE);
ucb1400_adc_enable(ucb->ac97);
x_res = ucb1400_ts_read_xres(ucb);
y_res = ucb1400_ts_read_yres(ucb);

View File

@ -73,6 +73,10 @@
#define UCB_ADC_DATA 0x68
#define UCB_ADC_DAT_VALID (1 << 15)
#define UCB_FCSR 0x6c
#define UCB_FCSR_AVE (1 << 12)
#define UCB_ADC_DAT_MASK 0x3ff
#define UCB_ID 0x7e