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path: root/drivers/input/touchscreen/ti_am335x_tsc.c
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Diffstat (limited to 'drivers/input/touchscreen/ti_am335x_tsc.c')
-rw-r--r--drivers/input/touchscreen/ti_am335x_tsc.c197
1 files changed, 111 insertions, 86 deletions
diff --git a/drivers/input/touchscreen/ti_am335x_tsc.c b/drivers/input/touchscreen/ti_am335x_tsc.c
index 004f1346a957..191a1b87895f 100644
--- a/drivers/input/touchscreen/ti_am335x_tsc.c
+++ b/drivers/input/touchscreen/ti_am335x_tsc.c
@@ -26,6 +26,7 @@
#include <linux/delay.h>
#include <linux/of.h>
#include <linux/of_device.h>
+#include <linux/sort.h>
#include <linux/mfd/ti_am335x_tscadc.h>
@@ -52,6 +53,7 @@ struct titsc {
u32 bit_xp, bit_xn, bit_yp, bit_yn;
u32 inp_xp, inp_xn, inp_yp, inp_yn;
u32 step_mask;
+ u32 charge_delay;
};
static unsigned int titsc_readl(struct titsc *ts, unsigned int reg)
@@ -121,7 +123,7 @@ 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 +142,11 @@ 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);
}
@@ -164,22 +168,20 @@ 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);
}
- /* Charge step configuration */
- config = ts_dev->bit_xp | ts_dev->bit_yn |
- STEPCHARGE_RFP_XPUL | STEPCHARGE_RFM_XNUR |
- STEPCHARGE_INM_AN1 | STEPCHARGE_INP(ts_dev->inp_yp);
+ /* Make CHARGECONFIG same as IDLECONFIG */
+ config = titsc_readl(ts_dev, REG_IDLECONFIG);
titsc_writel(ts_dev, REG_CHARGECONFIG, config);
- titsc_writel(ts_dev, REG_CHARGEDELAY, CHARGEDLY_OPENDLY);
+ titsc_writel(ts_dev, REG_CHARGEDELAY, ts_dev->charge_delay);
- /* 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 |
@@ -194,73 +196,104 @@ 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);
}
+static int titsc_cmp_coord(const void *a, const void *b)
+{
+ return *(int *)a - *(int *)b;
+}
+
static void titsc_read_coordinates(struct titsc *ts_dev,
u32 *x, u32 *y, u32 *z1, u32 *z2)
{
- unsigned int fifocount = titsc_readl(ts_dev, REG_FIFO0CNT);
- unsigned int prev_val_x = ~0, prev_val_y = ~0;
- unsigned int prev_diff_x = ~0, prev_diff_y = ~0;
- unsigned int read, diff;
- unsigned int i, channel;
+ unsigned int yvals[7], xvals[7];
+ unsigned int i, xsum = 0, ysum = 0;
unsigned int creads = ts_dev->coordinate_readouts;
- *z1 = *z2 = 0;
- if (fifocount % (creads * 2 + 2))
- fifocount -= fifocount % (creads * 2 + 2);
- /*
- * Delta filter is used to remove large variations in sampled
- * values from ADC. The filter tries to predict where the next
- * coordinate could be. This is done by taking a previous
- * coordinate and subtracting it form current one. Further the
- * algorithm compares the difference with that of a present value,
- * if true the value is reported to the sub system.
- */
- for (i = 0; i < fifocount; i++) {
- read = titsc_readl(ts_dev, REG_FIFO0);
-
- channel = (read & 0xf0000) >> 16;
- read &= 0xfff;
- if (channel < creads) {
- diff = abs(read - prev_val_x);
- if (diff < prev_diff_x) {
- prev_diff_x = diff;
- *x = read;
- }
- prev_val_x = read;
+ for (i = 0; i < creads; i++) {
+ yvals[i] = titsc_readl(ts_dev, REG_FIFO0);
+ yvals[i] &= 0xfff;
+ }
- } else if (channel < creads * 2) {
- diff = abs(read - prev_val_y);
- if (diff < prev_diff_y) {
- prev_diff_y = diff;
- *y = read;
- }
- prev_val_y = read;
+ *z1 = titsc_readl(ts_dev, REG_FIFO0);
+ *z1 &= 0xfff;
+ *z2 = titsc_readl(ts_dev, REG_FIFO0);
+ *z2 &= 0xfff;
- } else if (channel < creads * 2 + 1) {
- *z1 = read;
+ for (i = 0; i < creads; i++) {
+ xvals[i] = titsc_readl(ts_dev, REG_FIFO0);
+ xvals[i] &= 0xfff;
+ }
- } else if (channel < creads * 2 + 2) {
- *z2 = read;
+ /*
+ * If co-ordinates readouts is less than 4 then
+ * report the average. In case of 4 or more
+ * readouts, sort the co-ordinate samples, drop
+ * min and max values and report the average of
+ * remaining values.
+ */
+ if (creads <= 3) {
+ for (i = 0; i < creads; i++) {
+ ysum += yvals[i];
+ xsum += xvals[i];
}
+ ysum /= creads;
+ xsum /= creads;
+ } else {
+ sort(yvals, creads, sizeof(unsigned int),
+ titsc_cmp_coord, NULL);
+ sort(xvals, creads, sizeof(unsigned int),
+ titsc_cmp_coord, NULL);
+ for (i = 1; i < creads - 1; i++) {
+ ysum += yvals[i];
+ xsum += xvals[i];
+ }
+ ysum /= creads - 2;
+ xsum /= creads - 2;
}
+ *y = ysum;
+ *x = xsum;
}
static irqreturn_t titsc_irq(int irq, void *dev)
{
struct titsc *ts_dev = dev;
struct input_dev *input_dev = ts_dev->input;
- unsigned int status, irqclr = 0;
+ unsigned int fsm, status, irqclr = 0;
unsigned int x = 0, y = 0;
unsigned int z1, z2, z;
- unsigned int fsm;
- status = titsc_readl(ts_dev, REG_IRQSTATUS);
+ status = titsc_readl(ts_dev, REG_RAWIRQSTATUS);
+ if (status & IRQENB_HW_PEN) {
+ ts_dev->pen_down = true;
+ titsc_writel(ts_dev, REG_IRQWAKEUP, 0x00);
+ titsc_writel(ts_dev, REG_IRQCLR, IRQENB_HW_PEN);
+ irqclr |= IRQENB_HW_PEN;
+ }
+
+ if (status & IRQENB_PENUP) {
+ fsm = titsc_readl(ts_dev, REG_ADCFSM);
+ if (fsm == ADCFSM_STEPID) {
+ ts_dev->pen_down = false;
+ input_report_key(input_dev, BTN_TOUCH, 0);
+ input_report_abs(input_dev, ABS_PRESSURE, 0);
+ input_sync(input_dev);
+ } else {
+ ts_dev->pen_down = true;
+ }
+ irqclr |= IRQENB_PENUP;
+ }
+
+ if (status & IRQENB_EOS)
+ irqclr |= IRQENB_EOS;
+
/*
* ADC and touchscreen share the IRQ line.
* FIFO1 interrupts are used by ADC. Handle FIFO0 IRQs here only
@@ -291,37 +324,11 @@ static irqreturn_t titsc_irq(int irq, void *dev)
}
irqclr |= IRQENB_FIFO0THRES;
}
-
- /*
- * Time for sequencer to settle, to read
- * correct state of the sequencer.
- */
- udelay(SEQ_SETTLE);
-
- status = titsc_readl(ts_dev, REG_RAWIRQSTATUS);
- if (status & IRQENB_PENUP) {
- /* Pen up event */
- fsm = titsc_readl(ts_dev, REG_ADCFSM);
- if (fsm == ADCFSM_STEPID) {
- ts_dev->pen_down = false;
- input_report_key(input_dev, BTN_TOUCH, 0);
- input_report_abs(input_dev, ABS_PRESSURE, 0);
- input_sync(input_dev);
- } else {
- ts_dev->pen_down = true;
- }
- irqclr |= IRQENB_PENUP;
- }
-
- if (status & IRQENB_HW_PEN) {
-
- titsc_writel(ts_dev, REG_IRQWAKEUP, 0x00);
- titsc_writel(ts_dev, REG_IRQCLR, IRQENB_HW_PEN);
- }
-
if (irqclr) {
titsc_writel(ts_dev, REG_IRQSTATUS, irqclr);
- am335x_tsc_se_set_cache(ts_dev->mfd_tscadc, ts_dev->step_mask);
+ if (status & IRQENB_EOS)
+ am335x_tsc_se_set_cache(ts_dev->mfd_tscadc,
+ ts_dev->step_mask);
return IRQ_HANDLED;
}
return IRQ_NONE;
@@ -368,6 +375,23 @@ static int titsc_parse_dt(struct platform_device *pdev,
if (err < 0)
return err;
+ if (ts_dev->coordinate_readouts <= 0) {
+ dev_warn(&pdev->dev,
+ "invalid co-ordinate readouts, resetting it to 5\n");
+ ts_dev->coordinate_readouts = 5;
+ }
+
+ err = of_property_read_u32(node, "ti,charge-delay",
+ &ts_dev->charge_delay);
+ /*
+ * If ti,charge-delay value is not specified, then use
+ * CHARGEDLY_OPENDLY as the default value.
+ */
+ if (err < 0) {
+ ts_dev->charge_delay = CHARGEDLY_OPENDLY;
+ dev_warn(&pdev->dev, "ti,charge-delay not specified\n");
+ }
+
return of_property_read_u32_array(node, "ti,wire-config",
ts_dev->config_inp, ARRAY_SIZE(ts_dev->config_inp));
}
@@ -411,6 +435,7 @@ static int titsc_probe(struct platform_device *pdev)
}
titsc_writel(ts_dev, REG_IRQENABLE, IRQENB_FIFO0THRES);
+ titsc_writel(ts_dev, REG_IRQENABLE, IRQENB_EOS);
err = titsc_config_wires(ts_dev);
if (err) {
dev_err(&pdev->dev, "wrong i/p wire configuration\n");