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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.c291
1 files changed, 170 insertions, 121 deletions
diff --git a/drivers/input/touchscreen/ti_am335x_tsc.c b/drivers/input/touchscreen/ti_am335x_tsc.c
index e1c5300cacfc..93d659ff90aa 100644
--- a/drivers/input/touchscreen/ti_am335x_tsc.c
+++ b/drivers/input/touchscreen/ti_am335x_tsc.c
@@ -14,7 +14,6 @@
*/
-#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/err.h>
#include <linux/module.h>
@@ -26,7 +25,8 @@
#include <linux/io.h>
#include <linux/delay.h>
#include <linux/of.h>
-#include <linux/of_device.h>
+#include <linux/sort.h>
+#include <linux/pm_wakeirq.h>
#include <linux/mfd/ti_am335x_tscadc.h>
@@ -34,6 +34,8 @@
#define SEQ_SETTLE 275
#define MAX_12BIT ((1 << 12) - 1)
+#define TSC_IRQENB_MASK (IRQENB_FIFO0THRES | IRQENB_EOS | IRQENB_HW_PEN)
+
static const int config_pins[] = {
STEPCONFIG_XPP,
STEPCONFIG_XNN,
@@ -44,6 +46,7 @@ static const int config_pins[] = {
struct titsc {
struct input_dev *input;
struct ti_tscadc_dev *mfd_tscadc;
+ struct device *dev;
unsigned int irq;
unsigned int wires;
unsigned int x_plate_resistance;
@@ -52,6 +55,8 @@ struct titsc {
u32 config_inp[4];
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)
@@ -120,12 +125,13 @@ static int titsc_config_wires(struct titsc *ts_dev)
static void titsc_step_config(struct titsc *ts_dev)
{
unsigned int config;
- int i;
- int end_step;
+ int i, n;
+ int end_step, first_step, tsc_steps;
u32 stepenable;
config = STEPCONFIG_MODE_HWSYNC |
- STEPCONFIG_AVG_16 | ts_dev->bit_xp;
+ STEPCONFIG_AVG_16 | ts_dev->bit_xp |
+ STEPCONFIG_INM_ADCREFM;
switch (ts_dev->wires) {
case 4:
config |= STEPCONFIG_INP(ts_dev->inp_yp) | ts_dev->bit_xn;
@@ -140,14 +146,17 @@ 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;
+ n = 0;
+ 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);
+ titsc_writel(ts_dev, REG_STEPDELAY(i),
+ n++ == 0 ? STEPCONFIG_OPENDLY : 0);
}
- config = 0;
config = STEPCONFIG_MODE_HWSYNC |
STEPCONFIG_AVG_16 | ts_dev->bit_yn |
STEPCONFIG_INM_ADCREFM;
@@ -157,29 +166,29 @@ static void titsc_step_config(struct titsc *ts_dev)
break;
case 5:
config |= ts_dev->bit_xp | STEPCONFIG_INP_AN4 |
- ts_dev->bit_xn | ts_dev->bit_yp;
+ STEPCONFIG_XNP | STEPCONFIG_YPN;
break;
case 8:
config |= ts_dev->bit_yp | STEPCONFIG_INP(ts_dev->inp_xp);
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;
+ n = 0;
+ 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);
+ titsc_writel(ts_dev, REG_STEPDELAY(i),
+ n++ == 0 ? STEPCONFIG_OPENDLY : 0);
}
- /* 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 |
@@ -189,77 +198,116 @@ static void titsc_step_config(struct titsc *ts_dev)
STEPCONFIG_OPENDLY);
end_step++;
- config |= STEPCONFIG_INP(ts_dev->inp_yn);
+ config = STEPCONFIG_MODE_HWSYNC |
+ STEPCONFIG_AVG_16 | ts_dev->bit_yp |
+ ts_dev->bit_xn | STEPCONFIG_INM_ADCREFM |
+ STEPCONFIG_INP(ts_dev->inp_yn);
titsc_writel(ts_dev, REG_STEPCONFIG(end_step), config);
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;
- am335x_tsc_se_set(ts_dev->mfd_tscadc, stepenable);
+ /* 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;
+ irqclr |= IRQENB_HW_PEN;
+ pm_stay_awake(ts_dev->dev);
+ }
+
+ 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);
+ pm_relax(ts_dev->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
+ */
if (status & IRQENB_FIFO0THRES) {
titsc_read_coordinates(ts_dev, &x, &y, &z1, &z2);
@@ -268,7 +316,7 @@ static irqreturn_t titsc_irq(int irq, void *dev)
/*
* Calculate pressure using formula
* Resistance(touch) = x plate resistance *
- * x postion/4096 * ((z2 / z1) - 1)
+ * x position/4096 * ((z2 / z1) - 1)
*/
z = z1 - z2;
z *= x;
@@ -286,37 +334,11 @@ 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_update(ts_dev->mfd_tscadc);
+ if (status & IRQENB_EOS)
+ am335x_tsc_se_set_cache(ts_dev->mfd_tscadc,
+ ts_dev->step_mask);
return IRQ_HANDLED;
}
return IRQ_NONE;
@@ -348,11 +370,38 @@ static int titsc_parse_dt(struct platform_device *pdev,
if (err < 0)
return err;
- err = of_property_read_u32(node, "ti,coordiante-readouts",
+ /*
+ * Try with the new binding first. If it fails, try again with
+ * bogus, miss-spelled version.
+ */
+ err = of_property_read_u32(node, "ti,coordinate-readouts",
&ts_dev->coordinate_readouts);
+ if (err < 0) {
+ dev_warn(&pdev->dev, "please use 'ti,coordinate-readouts' instead\n");
+ err = of_property_read_u32(node, "ti,coordiante-readouts",
+ &ts_dev->coordinate_readouts);
+ }
+
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));
}
@@ -369,7 +418,7 @@ static int titsc_probe(struct platform_device *pdev)
int err;
/* Allocate memory for device */
- ts_dev = kzalloc(sizeof(struct titsc), GFP_KERNEL);
+ ts_dev = kzalloc(sizeof(*ts_dev), GFP_KERNEL);
input_dev = input_allocate_device();
if (!ts_dev || !input_dev) {
dev_err(&pdev->dev, "failed to allocate memory.\n");
@@ -381,6 +430,7 @@ static int titsc_probe(struct platform_device *pdev)
ts_dev->mfd_tscadc = tscadc_dev;
ts_dev->input = input_dev;
ts_dev->irq = tscadc_dev->irq;
+ ts_dev->dev = &pdev->dev;
err = titsc_parse_dt(pdev, ts_dev);
if (err) {
@@ -389,13 +439,20 @@ static int titsc_probe(struct platform_device *pdev)
}
err = request_irq(ts_dev->irq, titsc_irq,
- 0, pdev->dev.driver->name, ts_dev);
+ IRQF_SHARED, pdev->dev.driver->name, ts_dev);
if (err) {
dev_err(&pdev->dev, "failed to allocate irq.\n");
goto err_free_mem;
}
+ device_init_wakeup(&pdev->dev, true);
+ err = dev_pm_set_wake_irq(&pdev->dev, ts_dev->irq);
+ if (err)
+ dev_err(&pdev->dev, "irq wake enable failed.\n");
+
+ titsc_writel(ts_dev, REG_IRQSTATUS, TSC_IRQENB_MASK);
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");
@@ -424,6 +481,8 @@ static int titsc_probe(struct platform_device *pdev)
return 0;
err_free_irq:
+ dev_pm_clear_wake_irq(&pdev->dev);
+ device_init_wakeup(&pdev->dev, false);
free_irq(ts_dev->irq, ts_dev);
err_free_mem:
input_free_device(input_dev);
@@ -431,11 +490,13 @@ err_free_mem:
return err;
}
-static int titsc_remove(struct platform_device *pdev)
+static void titsc_remove(struct platform_device *pdev)
{
struct titsc *ts_dev = platform_get_drvdata(pdev);
u32 steps;
+ dev_pm_clear_wake_irq(&pdev->dev);
+ device_init_wakeup(&pdev->dev, false);
free_irq(ts_dev->irq, ts_dev);
/* total steps followed by the enable mask */
@@ -446,18 +507,15 @@ static int titsc_remove(struct platform_device *pdev)
input_unregister_device(ts_dev->input);
kfree(ts_dev);
- return 0;
}
-#ifdef CONFIG_PM
static int titsc_suspend(struct device *dev)
{
struct titsc *ts_dev = dev_get_drvdata(dev);
- struct ti_tscadc_dev *tscadc_dev;
unsigned int idle;
- tscadc_dev = ti_tscadc_dev_get(to_platform_device(dev));
- if (device_may_wakeup(tscadc_dev->dev)) {
+ if (device_may_wakeup(dev)) {
+ titsc_writel(ts_dev, REG_IRQSTATUS, TSC_IRQENB_MASK);
idle = titsc_readl(ts_dev, REG_IRQENABLE);
titsc_writel(ts_dev, REG_IRQENABLE,
(idle | IRQENB_HW_PEN));
@@ -469,13 +527,12 @@ static int titsc_suspend(struct device *dev)
static int titsc_resume(struct device *dev)
{
struct titsc *ts_dev = dev_get_drvdata(dev);
- struct ti_tscadc_dev *tscadc_dev;
- tscadc_dev = ti_tscadc_dev_get(to_platform_device(dev));
- if (device_may_wakeup(tscadc_dev->dev)) {
+ if (device_may_wakeup(dev)) {
titsc_writel(ts_dev, REG_IRQWAKEUP,
0x00);
titsc_writel(ts_dev, REG_IRQCLR, IRQENB_HW_PEN);
+ pm_relax(dev);
}
titsc_step_config(ts_dev);
titsc_writel(ts_dev, REG_FIFO0THR,
@@ -483,14 +540,7 @@ static int titsc_resume(struct device *dev)
return 0;
}
-static const struct dev_pm_ops titsc_pm_ops = {
- .suspend = titsc_suspend,
- .resume = titsc_resume,
-};
-#define TITSC_PM_OPS (&titsc_pm_ops)
-#else
-#define TITSC_PM_OPS NULL
-#endif
+static DEFINE_SIMPLE_DEV_PM_OPS(titsc_pm_ops, titsc_suspend, titsc_resume);
static const struct of_device_id ti_tsc_dt_ids[] = {
{ .compatible = "ti,am3359-tsc", },
@@ -502,10 +552,9 @@ static struct platform_driver ti_tsc_driver = {
.probe = titsc_probe,
.remove = titsc_remove,
.driver = {
- .name = "TI-am335x-tsc",
- .owner = THIS_MODULE,
- .pm = TITSC_PM_OPS,
- .of_match_table = of_match_ptr(ti_tsc_dt_ids),
+ .name = "TI-am335x-tsc",
+ .pm = pm_sleep_ptr(&titsc_pm_ops),
+ .of_match_table = ti_tsc_dt_ids,
},
};
module_platform_driver(ti_tsc_driver);
generated by cgit (git 2.34.1) at 2025-12-25 22:12:48 +0000