// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Freescale MXS LRADC touchscreen driver
*
* Copyright (c) 2012 DENX Software Engineering, GmbH.
* Copyright (c) 2017 Ksenija Stanojevic <[email protected]>
*
* Authors:
* Marek Vasut <[email protected]>
* Ksenija Stanojevic <[email protected]>
*/
#include <linux/device.h>
#include <linux/err.h>
#include <linux/input.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/mfd/core.h>
#include <linux/mfd/mxs-lradc.h>
#include <linux/of.h>
#include <linux/of_irq.h>
#include <linux/platform_device.h>
static const char * const mxs_lradc_ts_irq_names[] = {
"mxs-lradc-touchscreen",
"mxs-lradc-channel6",
"mxs-lradc-channel7",
};
/*
* Touchscreen handling
*/
enum mxs_lradc_ts_plate {
LRADC_TOUCH = 0,
LRADC_SAMPLE_X,
LRADC_SAMPLE_Y,
LRADC_SAMPLE_PRESSURE,
LRADC_SAMPLE_VALID,
};
struct mxs_lradc_ts {
struct mxs_lradc *lradc;
struct device *dev;
void __iomem *base;
/*
* When the touchscreen is enabled, we give it two private virtual
* channels: #6 and #7. This means that only 6 virtual channels (instead
* of 8) will be available for buffered capture.
*/
#define TOUCHSCREEN_VCHANNEL1 7
#define TOUCHSCREEN_VCHANNEL2 6
struct input_dev *ts_input;
enum mxs_lradc_ts_plate cur_plate; /* state machine */
bool ts_valid;
unsigned int ts_x_pos;
unsigned int ts_y_pos;
unsigned int ts_pressure;
/* handle touchscreen's physical behaviour */
/* samples per coordinate */
unsigned int over_sample_cnt;
/* time clocks between samples */
unsigned int over_sample_delay;
/* time in clocks to wait after the plates where switched */
unsigned int settling_delay;
spinlock_t lock;
};
struct state_info {
u32 mask;
u32 bit;
u32 x_plate;
u32 y_plate;
u32 pressure;
};
static struct state_info info[] = {
{LRADC_CTRL0_MX23_PLATE_MASK, LRADC_CTRL0_MX23_TOUCH_DETECT_ENABLE,
LRADC_CTRL0_MX23_XP | LRADC_CTRL0_MX23_XM,
LRADC_CTRL0_MX23_YP | LRADC_CTRL0_MX23_YM,
LRADC_CTRL0_MX23_YP | LRADC_CTRL0_MX23_XM},
{LRADC_CTRL0_MX28_PLATE_MASK, LRADC_CTRL0_MX28_TOUCH_DETECT_ENABLE,
LRADC_CTRL0_MX28_XPPSW | LRADC_CTRL0_MX28_XNNSW,
LRADC_CTRL0_MX28_YPPSW | LRADC_CTRL0_MX28_YNNSW,
LRADC_CTRL0_MX28_YPPSW | LRADC_CTRL0_MX28_XNNSW}
};
static bool mxs_lradc_check_touch_event(struct mxs_lradc_ts *ts)
{
return !!(readl(ts->base + LRADC_STATUS) &
LRADC_STATUS_TOUCH_DETECT_RAW);
}
static void mxs_lradc_map_ts_channel(struct mxs_lradc_ts *ts, unsigned int vch,
unsigned int ch)
{
writel(LRADC_CTRL4_LRADCSELECT_MASK(vch),
ts->base + LRADC_CTRL4 + STMP_OFFSET_REG_CLR);
writel(LRADC_CTRL4_LRADCSELECT(vch, ch),
ts->base + LRADC_CTRL4 + STMP_OFFSET_REG_SET);
}
static void mxs_lradc_setup_ts_channel(struct mxs_lradc_ts *ts, unsigned int ch)
{
/*
* prepare for oversampling conversion
*
* from the datasheet:
* "The ACCUMULATE bit in the appropriate channel register
* HW_LRADC_CHn must be set to 1 if NUM_SAMPLES is greater then 0;
* otherwise, the IRQs will not fire."
*/
writel(LRADC_CH_ACCUMULATE |
LRADC_CH_NUM_SAMPLES(ts->over_sample_cnt - 1),
ts->base + LRADC_CH(ch));
/* from the datasheet:
* "Software must clear this register in preparation for a
* multi-cycle accumulation.
*/
writel(LRADC_CH_VALUE_MASK,
ts->base + LRADC_CH(ch) + STMP_OFFSET_REG_CLR);
/*
* prepare the delay/loop unit according to the oversampling count
*
* from the datasheet:
* "The DELAY fields in HW_LRADC_DELAY0, HW_LRADC_DELAY1,
* HW_LRADC_DELAY2, and HW_LRADC_DELAY3 must be non-zero; otherwise,
* the LRADC will not trigger the delay group."
*/
writel(LRADC_DELAY_TRIGGER(1 << ch) | LRADC_DELAY_TRIGGER_DELAYS(0) |
LRADC_DELAY_LOOP(ts->over_sample_cnt - 1) |
LRADC_DELAY_DELAY(ts->over_sample_delay - 1),
ts->base + LRADC_DELAY(3));
writel(LRADC_CTRL1_LRADC_IRQ(ch),
ts->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);
/*
* after changing the touchscreen plates setting
* the signals need some initial time to settle. Start the
* SoC's delay unit and start the conversion later
* and automatically.
*/
writel(LRADC_DELAY_TRIGGER(0) | LRADC_DELAY_TRIGGER_DELAYS(BIT(3)) |
LRADC_DELAY_KICK | LRADC_DELAY_DELAY(ts->settling_delay),
ts->base + LRADC_DELAY(2));
}
/*
* Pressure detection is special:
* We want to do both required measurements for the pressure detection in
* one turn. Use the hardware features to chain both conversions and let the
* hardware report one interrupt if both conversions are done
*/
static void mxs_lradc_setup_ts_pressure(struct mxs_lradc_ts *ts,
unsigned int ch1, unsigned int ch2)
{
u32 reg;
/*
* prepare for oversampling conversion
*
* from the datasheet:
* "The ACCUMULATE bit in the appropriate channel register
* HW_LRADC_CHn must be set to 1 if NUM_SAMPLES is greater then 0;
* otherwise, the IRQs will not fire."
*/
reg = LRADC_CH_ACCUMULATE |
LRADC_CH_NUM_SAMPLES(ts->over_sample_cnt - 1);
writel(reg, ts->base + LRADC_CH(ch1));
writel(reg, ts->base + LRADC_CH(ch2));
/* from the datasheet:
* "Software must clear this register in preparation for a
* multi-cycle accumulation.
*/
writel(LRADC_CH_VALUE_MASK,
ts->base + LRADC_CH(ch1) + STMP_OFFSET_REG_CLR);
writel(LRADC_CH_VALUE_MASK,
ts->base + LRADC_CH(ch2) + STMP_OFFSET_REG_CLR);
/* prepare the delay/loop unit according to the oversampling count */
writel(LRADC_DELAY_TRIGGER(1 << ch1) | LRADC_DELAY_TRIGGER(1 << ch2) |
LRADC_DELAY_TRIGGER_DELAYS(0) |
LRADC_DELAY_LOOP(ts->over_sample_cnt - 1) |
LRADC_DELAY_DELAY(ts->over_sample_delay - 1),
ts->base + LRADC_DELAY(3));
writel(LRADC_CTRL1_LRADC_IRQ(ch2),
ts->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);
/*
* after changing the touchscreen plates setting
* the signals need some initial time to settle. Start the
* SoC's delay unit and start the conversion later
* and automatically.
*/
writel(LRADC_DELAY_TRIGGER(0) | LRADC_DELAY_TRIGGER_DELAYS(BIT(3)) |
LRADC_DELAY_KICK | LRADC_DELAY_DELAY(ts->settling_delay),
ts->base + LRADC_DELAY(2));
}
static unsigned int mxs_lradc_ts_read_raw_channel(struct mxs_lradc_ts *ts,
unsigned int channel)
{
u32 reg;
unsigned int num_samples, val;
reg = readl(ts->base + LRADC_CH(channel));
if (reg & LRADC_CH_ACCUMULATE)
num_samples = ts->over_sample_cnt;
else
num_samples = 1;
val = (reg & LRADC_CH_VALUE_MASK) >> LRADC_CH_VALUE_OFFSET;
return val / num_samples;
}
static unsigned int mxs_lradc_read_ts_pressure(struct mxs_lradc_ts *ts,
unsigned int ch1, unsigned int ch2)
{
u32 reg, mask;
unsigned int pressure, m1, m2;
mask = LRADC_CTRL1_LRADC_IRQ(ch1) | LRADC_CTRL1_LRADC_IRQ(ch2);
reg = readl(ts->base + LRADC_CTRL1) & mask;
while (reg != mask) {
reg = readl(ts->base + LRADC_CTRL1) & mask;
dev_dbg(ts->dev, "One channel is still busy: %X\n", reg);
}
m1 = mxs_lradc_ts_read_raw_channel(ts, ch1);
m2 = mxs_lradc_ts_read_raw_channel(ts, ch2);
if (m2 == 0) {
dev_warn(ts->dev, "Cannot calculate pressure\n");
return 1 << (LRADC_RESOLUTION - 1);
}
/* simply scale the value from 0 ... max ADC resolution */
pressure = m1;
pressure *= (1 << LRADC_RESOLUTION);
pressure /= m2;
dev_dbg(ts->dev, "Pressure = %u\n", pressure);
return pressure;
}
#define TS_CH_XP 2
#define TS_CH_YP 3
#define TS_CH_XM 4
#define TS_CH_YM 5
/*
* YP(open)--+-------------+
* | |--+
* | | |
* YM(-)--+-------------+ |
* +--------------+
* | |
* XP(weak+) XM(open)
*
* "weak+" means 200k Ohm VDDIO
* (-) means GND
*/
static void mxs_lradc_setup_touch_detection(struct mxs_lradc_ts *ts)
{
struct mxs_lradc *lradc = ts->lradc;
/*
* In order to detect a touch event the 'touch detect enable' bit
* enables:
* - a weak pullup to the X+ connector
* - a strong ground at the Y- connector
*/
writel(info[lradc->soc].mask,
ts->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);
writel(info[lradc->soc].bit,
ts->base + LRADC_CTRL0 + STMP_OFFSET_REG_SET);
}
/*
* YP(meas)--+-------------+
* | |--+
* | | |
* YM(open)--+-------------+ |
* +--------------+
* | |
* XP(+) XM(-)
*
* (+) means here 1.85 V
* (-) means here GND
*/
static void mxs_lradc_prepare_x_pos(struct mxs_lradc_ts *ts)
{
struct mxs_lradc *lradc = ts->lradc;
writel(info[lradc->soc].mask,
ts->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);
writel(info[lradc->soc].x_plate,
ts->base + LRADC_CTRL0 + STMP_OFFSET_REG_SET);
ts->cur_plate = LRADC_SAMPLE_X;
mxs_lradc_map_ts_channel(ts, TOUCHSCREEN_VCHANNEL1, TS_CH_YP);
mxs_lradc_setup_ts_channel(ts, TOUCHSCREEN_VCHANNEL1);
}
/*
* YP(+)--+-------------+
* | |--+
* | | |
* YM(-)--+-------------+ |
* +--------------+
* | |
* XP(open) XM(meas)
*
* (+) means here 1.85 V
* (-) means here GND
*/
static void mxs_lradc_prepare_y_pos(struct mxs_lradc_ts *ts)
{
struct mxs_lradc *lradc = ts->lradc;
writel(info[lradc->soc].mask,
ts->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);
writel(info[lradc->soc].y_plate,
ts->base + LRADC_CTRL0 + STMP_OFFSET_REG_SET);
ts->cur_plate = LRADC_SAMPLE_Y;
mxs_lradc_map_ts_channel(ts, TOUCHSCREEN_VCHANNEL1, TS_CH_XM);
mxs_lradc_setup_ts_channel(ts, TOUCHSCREEN_VCHANNEL1);
}
/*
* YP(+)--+-------------+
* | |--+
* | | |
* YM(meas)--+-------------+ |
* +--------------+
* | |
* XP(meas) XM(-)
*
* (+) means here 1.85 V
* (-) means here GND
*/
static void mxs_lradc_prepare_pressure(struct mxs_lradc_ts *ts)
{
struct mxs_lradc *lradc = ts->lradc;
writel(info[lradc->soc].mask,
ts->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);
writel(info[lradc->soc].pressure,
ts->base + LRADC_CTRL0 + STMP_OFFSET_REG_SET);
ts->cur_plate = LRADC_SAMPLE_PRESSURE;
mxs_lradc_map_ts_channel(ts, TOUCHSCREEN_VCHANNEL1, TS_CH_YM);
mxs_lradc_map_ts_channel(ts, TOUCHSCREEN_VCHANNEL2, TS_CH_XP);
mxs_lradc_setup_ts_pressure(ts, TOUCHSCREEN_VCHANNEL2,
TOUCHSCREEN_VCHANNEL1);
}
static void mxs_lradc_enable_touch_detection(struct mxs_lradc_ts *ts)
{
mxs_lradc_setup_touch_detection(ts);
ts->cur_plate = LRADC_TOUCH;
writel(LRADC_CTRL1_TOUCH_DETECT_IRQ | LRADC_CTRL1_TOUCH_DETECT_IRQ_EN,
ts->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);
writel(LRADC_CTRL1_TOUCH_DETECT_IRQ_EN,
ts->base + LRADC_CTRL1 + STMP_OFFSET_REG_SET);
}
static void mxs_lradc_start_touch_event(struct mxs_lradc_ts *ts)
{
writel(LRADC_CTRL1_TOUCH_DETECT_IRQ_EN,
ts->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);
writel(LRADC_CTRL1_LRADC_IRQ_EN(TOUCHSCREEN_VCHANNEL1),
ts->base + LRADC_CTRL1 + STMP_OFFSET_REG_SET);
/*
* start with the Y-pos, because it uses nearly the same plate
* settings like the touch detection
*/
mxs_lradc_prepare_y_pos(ts);
}
static void mxs_lradc_report_ts_event(struct mxs_lradc_ts *ts)
{
input_report_abs(ts->ts_input, ABS_X, ts->ts_x_pos);
input_report_abs(ts->ts_input, ABS_Y, ts->ts_y_pos);
input_report_abs(ts->ts_input, ABS_PRESSURE, ts->ts_pressure);
input_report_key(ts->ts_input, BTN_TOUCH, 1);
input_sync(ts->ts_input);
}
static void mxs_lradc_complete_touch_event(struct mxs_lradc_ts *ts)
{
mxs_lradc_setup_touch_detection(ts);
ts->cur_plate = LRADC_SAMPLE_VALID;
/*
* start a dummy conversion to burn time to settle the signals
* note: we are not interested in the conversion's value
*/
writel(0, ts->base + LRADC_CH(TOUCHSCREEN_VCHANNEL1));
writel(LRADC_CTRL1_LRADC_IRQ(TOUCHSCREEN_VCHANNEL1) |
LRADC_CTRL1_LRADC_IRQ(TOUCHSCREEN_VCHANNEL2),
ts->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);
writel(LRADC_DELAY_TRIGGER(1 << TOUCHSCREEN_VCHANNEL1) |
LRADC_DELAY_KICK | LRADC_DELAY_DELAY(10),
ts->base + LRADC_DELAY(2));
}
/*
* in order to avoid false measurements, report only samples where
* the surface is still touched after the position measurement
*/
static void mxs_lradc_finish_touch_event(struct mxs_lradc_ts *ts, bool valid)
{
/* if it is still touched, report the sample */
if (valid && mxs_lradc_check_touch_event(ts)) {
ts->ts_valid = true;
mxs_lradc_report_ts_event(ts);
}
/* if it is even still touched, continue with the next measurement */
if (mxs_lradc_check_touch_event(ts)) {
mxs_lradc_prepare_y_pos(ts);
return;
}
if (ts->ts_valid) {
/* signal the release */
ts->ts_valid = false;
input_report_key(ts->ts_input, BTN_TOUCH, 0);
input_sync(ts->ts_input);
}
/* if it is released, wait for the next touch via IRQ */
ts->cur_plate = LRADC_TOUCH;
writel(0, ts->base + LRADC_DELAY(2));
writel(0, ts->base + LRADC_DELAY(3));
writel(LRADC_CTRL1_TOUCH_DETECT_IRQ |
LRADC_CTRL1_LRADC_IRQ_EN(TOUCHSCREEN_VCHANNEL1) |
LRADC_CTRL1_LRADC_IRQ(TOUCHSCREEN_VCHANNEL1),
ts->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);
writel(LRADC_CTRL1_TOUCH_DETECT_IRQ_EN,
ts->base + LRADC_CTRL1 + STMP_OFFSET_REG_SET);
}
/* touchscreen's state machine */
static void mxs_lradc_handle_touch(struct mxs_lradc_ts *ts)
{
switch (ts->cur_plate) {
case LRADC_TOUCH:
if (mxs_lradc_check_touch_event(ts))
mxs_lradc_start_touch_event(ts);
writel(LRADC_CTRL1_TOUCH_DETECT_IRQ,
ts->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);
return;
case LRADC_SAMPLE_Y:
ts->ts_y_pos =
mxs_lradc_ts_read_raw_channel(ts, TOUCHSCREEN_VCHANNEL1);
mxs_lradc_prepare_x_pos(ts);
return;
case LRADC_SAMPLE_X:
ts->ts_x_pos =
mxs_lradc_ts_read_raw_channel(ts, TOUCHSCREEN_VCHANNEL1);
mxs_lradc_prepare_pressure(ts);
return;
case LRADC_SAMPLE_PRESSURE:
ts->ts_pressure =
mxs_lradc_read_ts_pressure(ts,
TOUCHSCREEN_VCHANNEL2,
TOUCHSCREEN_VCHANNEL1);
mxs_lradc_complete_touch_event(ts);
return;
case LRADC_SAMPLE_VALID:
mxs_lradc_finish_touch_event(ts, 1);
break;
}
}
/* IRQ Handling */
static irqreturn_t mxs_lradc_ts_handle_irq(int irq, void *data)
{
struct mxs_lradc_ts *ts = data;
struct mxs_lradc *lradc = ts->lradc;
unsigned long reg = readl(ts->base + LRADC_CTRL1);
u32 clr_irq = mxs_lradc_irq_mask(lradc);
const u32 ts_irq_mask =
LRADC_CTRL1_TOUCH_DETECT_IRQ |
LRADC_CTRL1_LRADC_IRQ(TOUCHSCREEN_VCHANNEL1) |
LRADC_CTRL1_LRADC_IRQ(TOUCHSCREEN_VCHANNEL2);
unsigned long flags;
if (!(reg & mxs_lradc_irq_mask(lradc)))
return IRQ_NONE;
if (reg & ts_irq_mask) {
spin_lock_irqsave(&ts->lock, flags);
mxs_lradc_handle_touch(ts);
spin_unlock_irqrestore(&ts->lock, flags);
/* Make sure we don't clear the next conversion's interrupt. */
clr_irq &= ~(LRADC_CTRL1_LRADC_IRQ(TOUCHSCREEN_VCHANNEL1) |
LRADC_CTRL1_LRADC_IRQ(TOUCHSCREEN_VCHANNEL2));
writel(reg & clr_irq,
ts->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);
}
return IRQ_HANDLED;
}
static int mxs_lradc_ts_open(struct input_dev *dev)
{
struct mxs_lradc_ts *ts = input_get_drvdata(dev);
/* Enable the touch-detect circuitry. */
mxs_lradc_enable_touch_detection(ts);
return 0;
}
static void mxs_lradc_ts_stop(struct mxs_lradc_ts *ts)
{
int i;
struct mxs_lradc *lradc = ts->lradc;
/* stop all interrupts from firing */
writel(LRADC_CTRL1_TOUCH_DETECT_IRQ_EN |
LRADC_CTRL1_LRADC_IRQ_EN(TOUCHSCREEN_VCHANNEL1) |
LRADC_CTRL1_LRADC_IRQ_EN(TOUCHSCREEN_VCHANNEL2),
ts->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);
/* Power-down touchscreen touch-detect circuitry. */
writel(info[lradc->soc].mask,
ts->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);
writel(lradc->buffer_vchans << LRADC_CTRL1_LRADC_IRQ_EN_OFFSET,
ts->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);
for (i = 1; i < LRADC_MAX_DELAY_CHANS; i++)
writel(0, ts->base + LRADC_DELAY(i));
}
static void mxs_lradc_ts_close(struct input_dev *dev)
{
struct mxs_lradc_ts *ts = input_get_drvdata(dev);
mxs_lradc_ts_stop(ts);
}
static void mxs_lradc_ts_hw_init(struct mxs_lradc_ts *ts)
{
struct mxs_lradc *lradc = ts->lradc;
/* Configure the touchscreen type */
if (lradc->soc == IMX28_LRADC) {
writel(LRADC_CTRL0_MX28_TOUCH_SCREEN_TYPE,
ts->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);
if (lradc->touchscreen_wire == MXS_LRADC_TOUCHSCREEN_5WIRE)
writel(LRADC_CTRL0_MX28_TOUCH_SCREEN_TYPE,
ts->base + LRADC_CTRL0 + STMP_OFFSET_REG_SET);
}
}
static int mxs_lradc_ts_register(struct mxs_lradc_ts *ts)
{
struct input_dev *input;
struct device *dev = ts->dev;
input = devm_input_allocate_device(dev);
if (!input)
return -ENOMEM;
input->name = "mxs-lradc-ts";
input->id.bustype = BUS_HOST;
input->open = mxs_lradc_ts_open;
input->close = mxs_lradc_ts_close;
__set_bit(INPUT_PROP_DIRECT, input->propbit);
input_set_capability(input, EV_KEY, BTN_TOUCH);
input_set_abs_params(input, ABS_X, 0, LRADC_SINGLE_SAMPLE_MASK, 0, 0);
input_set_abs_params(input, ABS_Y, 0, LRADC_SINGLE_SAMPLE_MASK, 0, 0);
input_set_abs_params(input, ABS_PRESSURE, 0, LRADC_SINGLE_SAMPLE_MASK,
0, 0);
ts->ts_input = input;
input_set_drvdata(input, ts);
return input_register_device(input);
}
static int mxs_lradc_ts_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct device_node *node = dev->parent->of_node;
struct mxs_lradc *lradc = dev_get_drvdata(dev->parent);
struct mxs_lradc_ts *ts;
int ret, irq, virq, i;
u32 ts_wires = 0, adapt;
ts = devm_kzalloc(dev, sizeof(*ts), GFP_KERNEL);
if (!ts)
return -ENOMEM;
platform_set_drvdata(pdev, ts);
ts->lradc = lradc;
ts->dev = dev;
spin_lock_init(&ts->lock);
ts->base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(ts->base))
return PTR_ERR(ts->base);
ret = of_property_read_u32(node, "fsl,lradc-touchscreen-wires",
&ts_wires);
if (ret)
return ret;
if (of_property_read_u32(node, "fsl,ave-ctrl", &adapt)) {
ts->over_sample_cnt = 4;
} else {
if (adapt >= 1 && adapt <= 32) {
ts->over_sample_cnt = adapt;
} else {
dev_err(ts->dev, "Invalid sample count (%u)\n",
adapt);
return -EINVAL;
}
}
if (of_property_read_u32(node, "fsl,ave-delay", &adapt)) {
ts->over_sample_delay = 2;
} else {
if (adapt >= 2 && adapt <= LRADC_DELAY_DELAY_MASK + 1) {
ts->over_sample_delay = adapt;
} else {
dev_err(ts->dev, "Invalid sample delay (%u)\n",
adapt);
return -EINVAL;
}
}
if (of_property_read_u32(node, "fsl,settling", &adapt)) {
ts->settling_delay = 10;
} else {
if (adapt >= 1 && adapt <= LRADC_DELAY_DELAY_MASK) {
ts->settling_delay = adapt;
} else {
dev_err(ts->dev, "Invalid settling delay (%u)\n",
adapt);
return -EINVAL;
}
}
ret = stmp_reset_block(ts->base);
if (ret)
return ret;
mxs_lradc_ts_hw_init(ts);
for (i = 0; i < 3; i++) {
irq = platform_get_irq_byname(pdev, mxs_lradc_ts_irq_names[i]);
if (irq < 0)
return irq;
virq = irq_of_parse_and_map(node, irq);
mxs_lradc_ts_stop(ts);
ret = devm_request_irq(dev, virq,
mxs_lradc_ts_handle_irq,
0, mxs_lradc_ts_irq_names[i], ts);
if (ret)
return ret;
}
return mxs_lradc_ts_register(ts);
}
static struct platform_driver mxs_lradc_ts_driver = {
.driver = {
.name = "mxs-lradc-ts",
},
.probe = mxs_lradc_ts_probe,
};
module_platform_driver(mxs_lradc_ts_driver);
MODULE_AUTHOR("Marek Vasut <[email protected]>");
MODULE_DESCRIPTION("Freescale MXS LRADC touchscreen driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:mxs-lradc-ts");
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