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path: root/drivers/input/touchscreen/imx6ul_tsc.c
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Diffstat (limited to 'drivers/input/touchscreen/imx6ul_tsc.c')
-rw-r--r--drivers/input/touchscreen/imx6ul_tsc.c83
1 files changed, 63 insertions, 20 deletions
diff --git a/drivers/input/touchscreen/imx6ul_tsc.c b/drivers/input/touchscreen/imx6ul_tsc.c
index 8275267eac25..7098e0a47019 100644
--- a/drivers/input/touchscreen/imx6ul_tsc.c
+++ b/drivers/input/touchscreen/imx6ul_tsc.c
@@ -21,17 +21,25 @@
#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)
#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)
+#define ADC_CONV_MODE_MASK (0x3 << 2)
#define ADC_IPG_CLK 0x00
+#define ADC_INPUT_CLK_MASK 0x3
#define ADC_CLK_DIV_8 (0x03 << 5)
+#define ADC_CLK_DIV_MASK (0x3 << 5)
#define ADC_SHORT_SAMPLE_MODE (0x0 << 4)
+#define ADC_SAMPLE_MODE_MASK (0x1 << 4)
#define ADC_HARDWARE_TRIGGER (0x1 << 13)
+#define ADC_AVGS_SHIFT 14
+#define ADC_AVGS_MASK (0x3 << 14)
#define SELECT_CHANNEL_4 0x04
#define SELECT_CHANNEL_1 0x01
#define DISABLE_CONVERSION_INT (0x0 << 7)
@@ -84,8 +92,10 @@ struct imx6ul_tsc {
struct clk *adc_clk;
struct gpio_desc *xnur_gpio;
- int measure_delay_time;
- int pre_charge_time;
+ u32 measure_delay_time;
+ u32 pre_charge_time;
+ bool average_enable;
+ u32 average_select;
struct completion completion;
};
@@ -96,17 +106,23 @@ struct imx6ul_tsc {
*/
static int imx6ul_adc_init(struct imx6ul_tsc *tsc)
{
- int adc_hc = 0;
- int adc_gc;
- int adc_gs;
- int adc_cfg;
- int timeout;
+ u32 adc_hc = 0;
+ u32 adc_gc;
+ u32 adc_gs;
+ u32 adc_cfg;
+ unsigned long timeout;
reinit_completion(&tsc->completion);
adc_cfg = readl(tsc->adc_regs + REG_ADC_CFG);
+ adc_cfg &= ~(ADC_CONV_MODE_MASK | ADC_INPUT_CLK_MASK);
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_enable) {
+ adc_cfg &= ~ADC_AVGS_MASK;
+ adc_cfg |= (tsc->average_select) << ADC_AVGS_SHIFT;
+ }
adc_cfg &= ~ADC_HARDWARE_TRIGGER;
writel(adc_cfg, tsc->adc_regs + REG_ADC_CFG);
@@ -118,6 +134,8 @@ 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_enable)
+ adc_gc |= ADC_AVGE;
writel(adc_gc, tsc->adc_regs + REG_ADC_GC);
timeout = wait_for_completion_timeout
@@ -148,7 +166,7 @@ static int imx6ul_adc_init(struct imx6ul_tsc *tsc)
*/
static void imx6ul_tsc_channel_config(struct imx6ul_tsc *tsc)
{
- int adc_hc0, adc_hc1, adc_hc2, adc_hc3, adc_hc4;
+ u32 adc_hc0, adc_hc1, adc_hc2, adc_hc3, adc_hc4;
adc_hc0 = DISABLE_CONVERSION_INT;
writel(adc_hc0, tsc->adc_regs + REG_ADC_HC0);
@@ -173,8 +191,8 @@ static void imx6ul_tsc_channel_config(struct imx6ul_tsc *tsc)
*/
static void imx6ul_tsc_set(struct imx6ul_tsc *tsc)
{
- int basic_setting = 0;
- int start;
+ u32 basic_setting = 0;
+ u32 start;
basic_setting |= tsc->measure_delay_time << 8;
basic_setting |= DETECT_4_WIRE_MODE | AUTO_MEASURE;
@@ -209,8 +227,8 @@ static int imx6ul_tsc_init(struct imx6ul_tsc *tsc)
static void imx6ul_tsc_disable(struct imx6ul_tsc *tsc)
{
- int tsc_flow;
- int adc_cfg;
+ u32 tsc_flow;
+ u32 adc_cfg;
/* TSC controller enters to idle status */
tsc_flow = readl(tsc->tsc_regs + REG_TSC_FLOW_CONTROL);
@@ -227,8 +245,8 @@ static void imx6ul_tsc_disable(struct imx6ul_tsc *tsc)
static bool tsc_wait_detect_mode(struct imx6ul_tsc *tsc)
{
unsigned long timeout = jiffies + msecs_to_jiffies(2);
- int state_machine;
- int debug_mode2;
+ u32 state_machine;
+ u32 debug_mode2;
do {
if (time_after(jiffies, timeout))
@@ -246,10 +264,10 @@ static bool tsc_wait_detect_mode(struct imx6ul_tsc *tsc)
static irqreturn_t tsc_irq_fn(int irq, void *dev_id)
{
struct imx6ul_tsc *tsc = dev_id;
- int status;
- int value;
- int x, y;
- int start;
+ u32 status;
+ u32 value;
+ u32 x, y;
+ u32 start;
status = readl(tsc->tsc_regs + REG_TSC_INT_STATUS);
@@ -289,8 +307,8 @@ static irqreturn_t tsc_irq_fn(int irq, void *dev_id)
static irqreturn_t adc_irq_fn(int irq, void *dev_id)
{
struct imx6ul_tsc *tsc = dev_id;
- int coco;
- int value;
+ u32 coco;
+ u32 value;
coco = readl(tsc->adc_regs + REG_ADC_HS);
if (coco & 0x01) {
@@ -346,6 +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)
@@ -450,6 +469,30 @@ static int imx6ul_tsc_probe(struct platform_device *pdev)
if (err)
tsc->pre_charge_time = 0xfff;
+ err = of_property_read_u32(np, "touchscreen-average-samples",
+ &average_samples);
+ if (err)
+ average_samples = 1;
+
+ 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;
+ }
+
err = input_register_device(tsc->input);
if (err) {
dev_err(&pdev->dev,
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