diff options
| -rw-r--r-- | Documentation/devicetree/bindings/input/touchscreen/imx6ul_tsc.txt | 8 | ||||
| -rw-r--r-- | drivers/input/touchscreen/imx6ul_tsc.c | 18 |
2 files changed, 26 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/input/touchscreen/imx6ul_tsc.txt b/Documentation/devicetree/bindings/input/touchscreen/imx6ul_tsc.txt index 853dff9..a66069f 100644 --- a/Documentation/devicetree/bindings/input/touchscreen/imx6ul_tsc.txt +++ b/Documentation/devicetree/bindings/input/touchscreen/imx6ul_tsc.txt @@ -17,6 +17,13 @@ Optional properties: This value depends on the touch screen. - pre-charge-time: the touch screen need some time to precharge. This value depends on the touch screen. +- average-samples: Number of data samples which are averaged for each read. + Valid values 0-4 + 0 = 1 sample + 1 = 4 samples + 2 = 8 samples + 3 = 16 samples + 4 = 32 samples Example: tsc: tsc@02040000 { @@ -32,5 +39,6 @@ Example: xnur-gpio = <&gpio1 3 GPIO_ACTIVE_LOW>; measure-delay-time = <0xfff>; pre-charge-time = <0xffff>; + average-samples = <4>; status = "okay"; }; diff --git a/drivers/input/touchscreen/imx6ul_tsc.c b/drivers/input/touchscreen/imx6ul_tsc.c index 8275267..00b336f 100644 --- a/drivers/input/touchscreen/imx6ul_tsc.c +++ b/drivers/input/touchscreen/imx6ul_tsc.c @@ -25,6 +25,7 @@ /* ADC configuration registers field define */ #define ADC_AIEN (0x1 << 7) #define ADC_CONV_DISABLE 0x1F +#define ADC_AVGE (0x1 << 5) #define ADC_CAL (0x1 << 7) #define ADC_CALF 0x2 #define ADC_12BIT_MODE (0x2 << 2) @@ -32,6 +33,7 @@ #define ADC_CLK_DIV_8 (0x03 << 5) #define ADC_SHORT_SAMPLE_MODE (0x0 << 4) #define ADC_HARDWARE_TRIGGER (0x1 << 13) +#define ADC_AVGS_SHIFT 14 #define SELECT_CHANNEL_4 0x04 #define SELECT_CHANNEL_1 0x01 #define DISABLE_CONVERSION_INT (0x0 << 7) @@ -86,6 +88,7 @@ struct imx6ul_tsc { int measure_delay_time; int pre_charge_time; + int average_samples; struct completion completion; }; @@ -107,6 +110,8 @@ static int imx6ul_adc_init(struct imx6ul_tsc *tsc) adc_cfg = readl(tsc->adc_regs + REG_ADC_CFG); adc_cfg |= ADC_12BIT_MODE | ADC_IPG_CLK; adc_cfg |= ADC_CLK_DIV_8 | ADC_SHORT_SAMPLE_MODE; + if (tsc->average_samples) + adc_cfg |= (tsc->average_samples - 1) << ADC_AVGS_SHIFT; adc_cfg &= ~ADC_HARDWARE_TRIGGER; writel(adc_cfg, tsc->adc_regs + REG_ADC_CFG); @@ -118,6 +123,8 @@ static int imx6ul_adc_init(struct imx6ul_tsc *tsc) /* start ADC calibration */ adc_gc = readl(tsc->adc_regs + REG_ADC_GC); adc_gc |= ADC_CAL; + if (tsc->average_samples) + adc_gc |= ADC_AVGE; writel(adc_gc, tsc->adc_regs + REG_ADC_GC); timeout = wait_for_completion_timeout @@ -450,6 +457,17 @@ static int imx6ul_tsc_probe(struct platform_device *pdev) if (err) tsc->pre_charge_time = 0xfff; + err = of_property_read_u32(np, "average-samples", + &tsc->average_samples); + if (err) + tsc->average_samples = 0; + + if (tsc->average_samples > 4) { + dev_err(&pdev->dev, "average-samples (%u) must be [0-4]\n", + tsc->average_samples); + return -EINVAL; + } + err = input_register_device(tsc->input); if (err) { dev_err(&pdev->dev, |
