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Input: imx6ul_tsc - generalize the averaging property

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Make the avarage-samples property a general touchscreen property
rather than imx6ul device specific.

Signed-off-by: Guy Shapiro <guy.shapiro@mobi-wize.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
This commit is contained in:
Guy Shapiro 2016-12-15 21:23:02 -08:00 committed by Dmitry Torokhov
parent 34888602eb
commit f43d3ec3a8
3 changed files with 32 additions and 18 deletions
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11
Documentation/devicetree/bindings/input/touchscreen/imx6ul_tsc.txt
View File

@ -17,13 +17,8 @@ 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
- touchscreen-average-samples: Number of data samples which are averaged for
each read. Valid values are 1, 4, 8, 16 and 32.
Example:
tsc: tsc@02040000 {
@ -39,6 +34,6 @@ Example:
xnur-gpio = <&gpio1 3 GPIO_ACTIVE_LOW>;
measure-delay-time = <0xfff>;
pre-charge-time = <0xffff>;
average-samples = <4>;
touchscreen-average-samples = <32>;
status = "okay";
};

3
Documentation/devicetree/bindings/input/touchscreen/touchscreen.txt
View File

@ -14,6 +14,9 @@ Optional properties for Touchscreens:
- touchscreen-fuzz-pressure : pressure noise value of the absolute input
device (arbitrary range dependent on the
controller)
- touchscreen-average-samples : Number of data samples which are averaged
for each read (valid values dependent on the
controller)
- touchscreen-inverted-x : X axis is inverted (boolean)
- touchscreen-inverted-y : Y axis is inverted (boolean)
- touchscreen-swapped-x-y : X and Y axis are swapped (boolean)

36
drivers/input/touchscreen/imx6ul_tsc.c
View File

@ -21,6 +21,7 @@
#include <linux/platform_device.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/log2.h>
/* ADC configuration registers field define */
#define ADC_AIEN (0x1 << 7)
@ -93,7 +94,8 @@ struct imx6ul_tsc {
u32 measure_delay_time;
u32 pre_charge_time;
u32 average_samples;
bool average_enable;
u32 average_select;
struct completion completion;
};
@ -117,9 +119,9 @@ static int imx6ul_adc_init(struct imx6ul_tsc *tsc)
adc_cfg |= ADC_12BIT_MODE | ADC_IPG_CLK;
adc_cfg &= ~(ADC_CLK_DIV_MASK | ADC_SAMPLE_MODE_MASK);
adc_cfg |= ADC_CLK_DIV_8 | ADC_SHORT_SAMPLE_MODE;
if (tsc->average_samples) {
if (tsc->average_enable) {
adc_cfg &= ~ADC_AVGS_MASK;
adc_cfg |= (tsc->average_samples - 1) << ADC_AVGS_SHIFT;
adc_cfg |= (tsc->average_select) << ADC_AVGS_SHIFT;
}
adc_cfg &= ~ADC_HARDWARE_TRIGGER;
writel(adc_cfg, tsc->adc_regs + REG_ADC_CFG);
@ -132,7 +134,7 @@ 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)
if (tsc->average_enable)
adc_gc |= ADC_AVGE;
writel(adc_gc, tsc->adc_regs + REG_ADC_GC);
@ -362,6 +364,7 @@ static int imx6ul_tsc_probe(struct platform_device *pdev)
int err;
int tsc_irq;
int adc_irq;
u32 average_samples;
tsc = devm_kzalloc(&pdev->dev, sizeof(*tsc), GFP_KERNEL);
if (!tsc)
@ -466,14 +469,27 @@ 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);
err = of_property_read_u32(np, "touchscreen-average-samples",
&average_samples);
if (err)
tsc->average_samples = 0;
average_samples = 1;
if (tsc->average_samples > 4) {
dev_err(&pdev->dev, "average-samples (%u) must be [0-4]\n",
tsc->average_samples);
switch (average_samples) {
case 1:
tsc->average_enable = false;
tsc->average_select = 0; /* value unused; initialize anyway */
break;
case 4:
case 8:
case 16:
case 32:
tsc->average_enable = true;
tsc->average_select = ilog2(average_samples) - 2;
break;
default:
dev_err(&pdev->dev,
"touchscreen-average-samples (%u) must be 1, 4, 8, 16 or 32\n",
average_samples);
return -EINVAL;
}