Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 1204 insertions, 0 deletions

diff --git a/drivers/input/misc/ad714x.c b/drivers/input/misc/ad714x.c
new file mode 100644
index 000000000..c9fa78933
--- /dev/null
+++ b/drivers/input/misc/ad714x.c
@@ -0,0 +1,1204 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * AD714X CapTouch Programmable Controller driver supporting AD7142/3/7/8/7A
+ *
+ * Copyright 2009-2011 Analog Devices Inc.
+ */
+
+#include <linux/device.h>
+#include <linux/export.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/slab.h>
+#include <linux/input/ad714x.h>
+#include <linux/module.h>
+#include "ad714x.h"
+
+#define AD714X_PWR_CTRL           0x0
+#define AD714X_STG_CAL_EN_REG     0x1
+#define AD714X_AMB_COMP_CTRL0_REG 0x2
+#define AD714X_PARTID_REG         0x17
+#define AD7142_PARTID             0xE620
+#define AD7143_PARTID             0xE630
+#define AD7147_PARTID             0x1470
+#define AD7148_PARTID             0x1480
+#define AD714X_STAGECFG_REG       0x80
+#define AD714X_SYSCFG_REG         0x0
+
+#define STG_LOW_INT_EN_REG     0x5
+#define STG_HIGH_INT_EN_REG    0x6
+#define STG_COM_INT_EN_REG     0x7
+#define STG_LOW_INT_STA_REG    0x8
+#define STG_HIGH_INT_STA_REG   0x9
+#define STG_COM_INT_STA_REG    0xA
+
+#define CDC_RESULT_S0          0xB
+#define CDC_RESULT_S1          0xC
+#define CDC_RESULT_S2          0xD
+#define CDC_RESULT_S3          0xE
+#define CDC_RESULT_S4          0xF
+#define CDC_RESULT_S5          0x10
+#define CDC_RESULT_S6          0x11
+#define CDC_RESULT_S7          0x12
+#define CDC_RESULT_S8          0x13
+#define CDC_RESULT_S9          0x14
+#define CDC_RESULT_S10         0x15
+#define CDC_RESULT_S11         0x16
+
+#define STAGE0_AMBIENT		0xF1
+#define STAGE1_AMBIENT		0x115
+#define STAGE2_AMBIENT		0x139
+#define STAGE3_AMBIENT		0x15D
+#define STAGE4_AMBIENT		0x181
+#define STAGE5_AMBIENT		0x1A5
+#define STAGE6_AMBIENT		0x1C9
+#define STAGE7_AMBIENT		0x1ED
+#define STAGE8_AMBIENT		0x211
+#define STAGE9_AMBIENT		0x234
+#define STAGE10_AMBIENT		0x259
+#define STAGE11_AMBIENT		0x27D
+
+#define PER_STAGE_REG_NUM      36
+#define STAGE_CFGREG_NUM       8
+#define SYS_CFGREG_NUM         8
+
+/*
+ * driver information which will be used to maintain the software flow
+ */
+enum ad714x_device_state { IDLE, JITTER, ACTIVE, SPACE };
+
+struct ad714x_slider_drv {
+	int highest_stage;
+	int abs_pos;
+	int flt_pos;
+	enum ad714x_device_state state;
+	struct input_dev *input;
+};
+
+struct ad714x_wheel_drv {
+	int abs_pos;
+	int flt_pos;
+	int pre_highest_stage;
+	int highest_stage;
+	enum ad714x_device_state state;
+	struct input_dev *input;
+};
+
+struct ad714x_touchpad_drv {
+	int x_highest_stage;
+	int x_flt_pos;
+	int x_abs_pos;
+	int y_highest_stage;
+	int y_flt_pos;
+	int y_abs_pos;
+	int left_ep;
+	int left_ep_val;
+	int right_ep;
+	int right_ep_val;
+	int top_ep;
+	int top_ep_val;
+	int bottom_ep;
+	int bottom_ep_val;
+	enum ad714x_device_state state;
+	struct input_dev *input;
+};
+
+struct ad714x_button_drv {
+	enum ad714x_device_state state;
+	/*
+	 * Unlike slider/wheel/touchpad, all buttons point to
+	 * same input_dev instance
+	 */
+	struct input_dev *input;
+};
+
+struct ad714x_driver_data {
+	struct ad714x_slider_drv *slider;
+	struct ad714x_wheel_drv *wheel;
+	struct ad714x_touchpad_drv *touchpad;
+	struct ad714x_button_drv *button;
+};
+
+/*
+ * information to integrate all things which will be private data
+ * of spi/i2c device
+ */
+
+static void ad714x_use_com_int(struct ad714x_chip *ad714x,
+				int start_stage, int end_stage)
+{
+	unsigned short data;
+	unsigned short mask;
+
+	mask = ((1 << (end_stage + 1)) - 1) - ((1 << start_stage) - 1);
+
+	ad714x->read(ad714x, STG_COM_INT_EN_REG, &data, 1);
+	data |= 1 << end_stage;
+	ad714x->write(ad714x, STG_COM_INT_EN_REG, data);
+
+	ad714x->read(ad714x, STG_HIGH_INT_EN_REG, &data, 1);
+	data &= ~mask;
+	ad714x->write(ad714x, STG_HIGH_INT_EN_REG, data);
+}
+
+static void ad714x_use_thr_int(struct ad714x_chip *ad714x,
+				int start_stage, int end_stage)
+{
+	unsigned short data;
+	unsigned short mask;
+
+	mask = ((1 << (end_stage + 1)) - 1) - ((1 << start_stage) - 1);
+
+	ad714x->read(ad714x, STG_COM_INT_EN_REG, &data, 1);
+	data &= ~(1 << end_stage);
+	ad714x->write(ad714x, STG_COM_INT_EN_REG, data);
+
+	ad714x->read(ad714x, STG_HIGH_INT_EN_REG, &data, 1);
+	data |= mask;
+	ad714x->write(ad714x, STG_HIGH_INT_EN_REG, data);
+}
+
+static int ad714x_cal_highest_stage(struct ad714x_chip *ad714x,
+					int start_stage, int end_stage)
+{
+	int max_res = 0;
+	int max_idx = 0;
+	int i;
+
+	for (i = start_stage; i <= end_stage; i++) {
+		if (ad714x->sensor_val[i] > max_res) {
+			max_res = ad714x->sensor_val[i];
+			max_idx = i;
+		}
+	}
+
+	return max_idx;
+}
+
+static int ad714x_cal_abs_pos(struct ad714x_chip *ad714x,
+				int start_stage, int end_stage,
+				int highest_stage, int max_coord)
+{
+	int a_param, b_param;
+
+	if (highest_stage == start_stage) {
+		a_param = ad714x->sensor_val[start_stage + 1];
+		b_param = ad714x->sensor_val[start_stage] +
+			ad714x->sensor_val[start_stage + 1];
+	} else if (highest_stage == end_stage) {
+		a_param = ad714x->sensor_val[end_stage] *
+			(end_stage - start_stage) +
+			ad714x->sensor_val[end_stage - 1] *
+			(end_stage - start_stage - 1);
+		b_param = ad714x->sensor_val[end_stage] +
+			ad714x->sensor_val[end_stage - 1];
+	} else {
+		a_param = ad714x->sensor_val[highest_stage] *
+			(highest_stage - start_stage) +
+			ad714x->sensor_val[highest_stage - 1] *
+			(highest_stage - start_stage - 1) +
+			ad714x->sensor_val[highest_stage + 1] *
+			(highest_stage - start_stage + 1);
+		b_param = ad714x->sensor_val[highest_stage] +
+			ad714x->sensor_val[highest_stage - 1] +
+			ad714x->sensor_val[highest_stage + 1];
+	}
+
+	return (max_coord / (end_stage - start_stage)) * a_param / b_param;
+}
+
+/*
+ * One button can connect to multi positive and negative of CDCs
+ * Multi-buttons can connect to same positive/negative of one CDC
+ */
+static void ad714x_button_state_machine(struct ad714x_chip *ad714x, int idx)
+{
+	struct ad714x_button_plat *hw = &ad714x->hw->button[idx];
+	struct ad714x_button_drv *sw = &ad714x->sw->button[idx];
+
+	switch (sw->state) {
+	case IDLE:
+		if (((ad714x->h_state & hw->h_mask) == hw->h_mask) &&
+		    ((ad714x->l_state & hw->l_mask) == hw->l_mask)) {
+			dev_dbg(ad714x->dev, "button %d touched\n", idx);
+			input_report_key(sw->input, hw->keycode, 1);
+			input_sync(sw->input);
+			sw->state = ACTIVE;
+		}
+		break;
+
+	case ACTIVE:
+		if (((ad714x->h_state & hw->h_mask) != hw->h_mask) ||
+		    ((ad714x->l_state & hw->l_mask) != hw->l_mask)) {
+			dev_dbg(ad714x->dev, "button %d released\n", idx);
+			input_report_key(sw->input, hw->keycode, 0);
+			input_sync(sw->input);
+			sw->state = IDLE;
+		}
+		break;
+
+	default:
+		break;
+	}
+}
+
+/*
+ * The response of a sensor is defined by the absolute number of codes
+ * between the current CDC value and the ambient value.
+ */
+static void ad714x_slider_cal_sensor_val(struct ad714x_chip *ad714x, int idx)
+{
+	struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx];
+	int i;
+
+	ad714x->read(ad714x, CDC_RESULT_S0 + hw->start_stage,
+			&ad714x->adc_reg[hw->start_stage],
+			hw->end_stage - hw->start_stage + 1);
+
+	for (i = hw->start_stage; i <= hw->end_stage; i++) {
+		ad714x->read(ad714x, STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
+				&ad714x->amb_reg[i], 1);
+
+		ad714x->sensor_val[i] =
+			abs(ad714x->adc_reg[i] - ad714x->amb_reg[i]);
+	}
+}
+
+static void ad714x_slider_cal_highest_stage(struct ad714x_chip *ad714x, int idx)
+{
+	struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx];
+	struct ad714x_slider_drv *sw = &ad714x->sw->slider[idx];
+
+	sw->highest_stage = ad714x_cal_highest_stage(ad714x, hw->start_stage,
+			hw->end_stage);
+
+	dev_dbg(ad714x->dev, "slider %d highest_stage:%d\n", idx,
+		sw->highest_stage);
+}
+
+/*
+ * The formulae are very straight forward. It uses the sensor with the
+ * highest response and the 2 adjacent ones.
+ * When Sensor 0 has the highest response, only sensor 0 and sensor 1
+ * are used in the calculations. Similarly when the last sensor has the
+ * highest response, only the last sensor and the second last sensors
+ * are used in the calculations.
+ *
+ * For i= idx_of_peak_Sensor-1 to i= idx_of_peak_Sensor+1
+ *         v += Sensor response(i)*i
+ *         w += Sensor response(i)
+ * POS=(Number_of_Positions_Wanted/(Number_of_Sensors_Used-1)) *(v/w)
+ */
+static void ad714x_slider_cal_abs_pos(struct ad714x_chip *ad714x, int idx)
+{
+	struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx];
+	struct ad714x_slider_drv *sw = &ad714x->sw->slider[idx];
+
+	sw->abs_pos = ad714x_cal_abs_pos(ad714x, hw->start_stage, hw->end_stage,
+		sw->highest_stage, hw->max_coord);
+
+	dev_dbg(ad714x->dev, "slider %d absolute position:%d\n", idx,
+		sw->abs_pos);
+}
+
+/*
+ * To minimise the Impact of the noise on the algorithm, ADI developed a
+ * routine that filters the CDC results after they have been read by the
+ * host processor.
+ * The filter used is an Infinite Input Response(IIR) filter implemented
+ * in firmware and attenuates the noise on the CDC results after they've
+ * been read by the host processor.
+ * Filtered_CDC_result = (Filtered_CDC_result * (10 - Coefficient) +
+ *				Latest_CDC_result * Coefficient)/10
+ */
+static void ad714x_slider_cal_flt_pos(struct ad714x_chip *ad714x, int idx)
+{
+	struct ad714x_slider_drv *sw = &ad714x->sw->slider[idx];
+
+	sw->flt_pos = (sw->flt_pos * (10 - 4) +
+			sw->abs_pos * 4)/10;
+
+	dev_dbg(ad714x->dev, "slider %d filter position:%d\n", idx,
+		sw->flt_pos);
+}
+
+static void ad714x_slider_use_com_int(struct ad714x_chip *ad714x, int idx)
+{
+	struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx];
+
+	ad714x_use_com_int(ad714x, hw->start_stage, hw->end_stage);
+}
+
+static void ad714x_slider_use_thr_int(struct ad714x_chip *ad714x, int idx)
+{
+	struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx];
+
+	ad714x_use_thr_int(ad714x, hw->start_stage, hw->end_stage);
+}
+
+static void ad714x_slider_state_machine(struct ad714x_chip *ad714x, int idx)
+{
+	struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx];
+	struct ad714x_slider_drv *sw = &ad714x->sw->slider[idx];
+	unsigned short h_state, c_state;
+	unsigned short mask;
+
+	mask = ((1 << (hw->end_stage + 1)) - 1) - ((1 << hw->start_stage) - 1);
+
+	h_state = ad714x->h_state & mask;
+	c_state = ad714x->c_state & mask;
+
+	switch (sw->state) {
+	case IDLE:
+		if (h_state) {
+			sw->state = JITTER;
+			/* In End of Conversion interrupt mode, the AD714X
+			 * continuously generates hardware interrupts.
+			 */
+			ad714x_slider_use_com_int(ad714x, idx);
+			dev_dbg(ad714x->dev, "slider %d touched\n", idx);
+		}
+		break;
+
+	case JITTER:
+		if (c_state == mask) {
+			ad714x_slider_cal_sensor_val(ad714x, idx);
+			ad714x_slider_cal_highest_stage(ad714x, idx);
+			ad714x_slider_cal_abs_pos(ad714x, idx);
+			sw->flt_pos = sw->abs_pos;
+			sw->state = ACTIVE;
+		}
+		break;
+
+	case ACTIVE:
+		if (c_state == mask) {
+			if (h_state) {
+				ad714x_slider_cal_sensor_val(ad714x, idx);
+				ad714x_slider_cal_highest_stage(ad714x, idx);
+				ad714x_slider_cal_abs_pos(ad714x, idx);
+				ad714x_slider_cal_flt_pos(ad714x, idx);
+				input_report_abs(sw->input, ABS_X, sw->flt_pos);
+				input_report_key(sw->input, BTN_TOUCH, 1);
+			} else {
+				/* When the user lifts off the sensor, configure
+				 * the AD714X back to threshold interrupt mode.
+				 */
+				ad714x_slider_use_thr_int(ad714x, idx);
+				sw->state = IDLE;
+				input_report_key(sw->input, BTN_TOUCH, 0);
+				dev_dbg(ad714x->dev, "slider %d released\n",
+					idx);
+			}
+			input_sync(sw->input);
+		}
+		break;
+
+	default:
+		break;
+	}
+}
+
+/*
+ * When the scroll wheel is activated, we compute the absolute position based
+ * on the sensor values. To calculate the position, we first determine the
+ * sensor that has the greatest response among the 8 sensors that constitutes
+ * the scrollwheel. Then we determined the 2 sensors on either sides of the
+ * sensor with the highest response and we apply weights to these sensors.
+ */
+static void ad714x_wheel_cal_highest_stage(struct ad714x_chip *ad714x, int idx)
+{
+	struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
+	struct ad714x_wheel_drv *sw = &ad714x->sw->wheel[idx];
+
+	sw->pre_highest_stage = sw->highest_stage;
+	sw->highest_stage = ad714x_cal_highest_stage(ad714x, hw->start_stage,
+			hw->end_stage);
+
+	dev_dbg(ad714x->dev, "wheel %d highest_stage:%d\n", idx,
+		sw->highest_stage);
+}
+
+static void ad714x_wheel_cal_sensor_val(struct ad714x_chip *ad714x, int idx)
+{
+	struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
+	int i;
+
+	ad714x->read(ad714x, CDC_RESULT_S0 + hw->start_stage,
+			&ad714x->adc_reg[hw->start_stage],
+			hw->end_stage - hw->start_stage + 1);
+
+	for (i = hw->start_stage; i <= hw->end_stage; i++) {
+		ad714x->read(ad714x, STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
+				&ad714x->amb_reg[i], 1);
+		if (ad714x->adc_reg[i] > ad714x->amb_reg[i])
+			ad714x->sensor_val[i] =
+				ad714x->adc_reg[i] - ad714x->amb_reg[i];
+		else
+			ad714x->sensor_val[i] = 0;
+	}
+}
+
+/*
+ * When the scroll wheel is activated, we compute the absolute position based
+ * on the sensor values. To calculate the position, we first determine the
+ * sensor that has the greatest response among the sensors that constitutes
+ * the scrollwheel. Then we determined the sensors on either sides of the
+ * sensor with the highest response and we apply weights to these sensors. The
+ * result of this computation gives us the mean value.
+ */
+
+static void ad714x_wheel_cal_abs_pos(struct ad714x_chip *ad714x, int idx)
+{
+	struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
+	struct ad714x_wheel_drv *sw = &ad714x->sw->wheel[idx];
+	int stage_num = hw->end_stage - hw->start_stage + 1;
+	int first_before, highest, first_after;
+	int a_param, b_param;
+
+	first_before = (sw->highest_stage + stage_num - 1) % stage_num;
+	highest = sw->highest_stage;
+	first_after = (sw->highest_stage + stage_num + 1) % stage_num;
+
+	a_param = ad714x->sensor_val[highest] *
+		(highest - hw->start_stage) +
+		ad714x->sensor_val[first_before] *
+		(highest - hw->start_stage - 1) +
+		ad714x->sensor_val[first_after] *
+		(highest - hw->start_stage + 1);
+	b_param = ad714x->sensor_val[highest] +
+		ad714x->sensor_val[first_before] +
+		ad714x->sensor_val[first_after];
+
+	sw->abs_pos = ((hw->max_coord / (hw->end_stage - hw->start_stage)) *
+			a_param) / b_param;
+
+	if (sw->abs_pos > hw->max_coord)
+		sw->abs_pos = hw->max_coord;
+	else if (sw->abs_pos < 0)
+		sw->abs_pos = 0;
+}
+
+static void ad714x_wheel_cal_flt_pos(struct ad714x_chip *ad714x, int idx)
+{
+	struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
+	struct ad714x_wheel_drv *sw = &ad714x->sw->wheel[idx];
+	if (((sw->pre_highest_stage == hw->end_stage) &&
+			(sw->highest_stage == hw->start_stage)) ||
+	    ((sw->pre_highest_stage == hw->start_stage) &&
+			(sw->highest_stage == hw->end_stage)))
+		sw->flt_pos = sw->abs_pos;
+	else
+		sw->flt_pos = ((sw->flt_pos * 30) + (sw->abs_pos * 71)) / 100;
+
+	if (sw->flt_pos > hw->max_coord)
+		sw->flt_pos = hw->max_coord;
+}
+
+static void ad714x_wheel_use_com_int(struct ad714x_chip *ad714x, int idx)
+{
+	struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
+
+	ad714x_use_com_int(ad714x, hw->start_stage, hw->end_stage);
+}
+
+static void ad714x_wheel_use_thr_int(struct ad714x_chip *ad714x, int idx)
+{
+	struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
+
+	ad714x_use_thr_int(ad714x, hw->start_stage, hw->end_stage);
+}
+
+static void ad714x_wheel_state_machine(struct ad714x_chip *ad714x, int idx)
+{
+	struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
+	struct ad714x_wheel_drv *sw = &ad714x->sw->wheel[idx];
+	unsigned short h_state, c_state;
+	unsigned short mask;
+
+	mask = ((1 << (hw->end_stage + 1)) - 1) - ((1 << hw->start_stage) - 1);
+
+	h_state = ad714x->h_state & mask;
+	c_state = ad714x->c_state & mask;
+
+	switch (sw->state) {
+	case IDLE:
+		if (h_state) {
+			sw->state = JITTER;
+			/* In End of Conversion interrupt mode, the AD714X
+			 * continuously generates hardware interrupts.
+			 */
+			ad714x_wheel_use_com_int(ad714x, idx);
+			dev_dbg(ad714x->dev, "wheel %d touched\n", idx);
+		}
+		break;
+
+	case JITTER:
+		if (c_state == mask)	{
+			ad714x_wheel_cal_sensor_val(ad714x, idx);
+			ad714x_wheel_cal_highest_stage(ad714x, idx);
+			ad714x_wheel_cal_abs_pos(ad714x, idx);
+			sw->flt_pos = sw->abs_pos;
+			sw->state = ACTIVE;
+		}
+		break;
+
+	case ACTIVE:
+		if (c_state == mask) {
+			if (h_state) {
+				ad714x_wheel_cal_sensor_val(ad714x, idx);
+				ad714x_wheel_cal_highest_stage(ad714x, idx);
+				ad714x_wheel_cal_abs_pos(ad714x, idx);
+				ad714x_wheel_cal_flt_pos(ad714x, idx);
+				input_report_abs(sw->input, ABS_WHEEL,
+					sw->flt_pos);
+				input_report_key(sw->input, BTN_TOUCH, 1);
+			} else {
+				/* When the user lifts off the sensor, configure
+				 * the AD714X back to threshold interrupt mode.
+				 */
+				ad714x_wheel_use_thr_int(ad714x, idx);
+				sw->state = IDLE;
+				input_report_key(sw->input, BTN_TOUCH, 0);
+
+				dev_dbg(ad714x->dev, "wheel %d released\n",
+					idx);
+			}
+			input_sync(sw->input);
+		}
+		break;
+
+	default:
+		break;
+	}
+}
+
+static void touchpad_cal_sensor_val(struct ad714x_chip *ad714x, int idx)
+{
+	struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
+	int i;
+
+	ad714x->read(ad714x, CDC_RESULT_S0 + hw->x_start_stage,
+			&ad714x->adc_reg[hw->x_start_stage],
+			hw->x_end_stage - hw->x_start_stage + 1);
+
+	for (i = hw->x_start_stage; i <= hw->x_end_stage; i++) {
+		ad714x->read(ad714x, STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
+				&ad714x->amb_reg[i], 1);
+		if (ad714x->adc_reg[i] > ad714x->amb_reg[i])
+			ad714x->sensor_val[i] =
+				ad714x->adc_reg[i] - ad714x->amb_reg[i];
+		else
+			ad714x->sensor_val[i] = 0;
+	}
+}
+
+static void touchpad_cal_highest_stage(struct ad714x_chip *ad714x, int idx)
+{
+	struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
+	struct ad714x_touchpad_drv *sw = &ad714x->sw->touchpad[idx];
+
+	sw->x_highest_stage = ad714x_cal_highest_stage(ad714x,
+		hw->x_start_stage, hw->x_end_stage);
+	sw->y_highest_stage = ad714x_cal_highest_stage(ad714x,
+		hw->y_start_stage, hw->y_end_stage);
+
+	dev_dbg(ad714x->dev,
+		"touchpad %d x_highest_stage:%d, y_highest_stage:%d\n",
+		idx, sw->x_highest_stage, sw->y_highest_stage);
+}
+
+/*
+ * If 2 fingers are touching the sensor then 2 peaks can be observed in the
+ * distribution.
+ * The arithmetic doesn't support to get absolute coordinates for multi-touch
+ * yet.
+ */
+static int touchpad_check_second_peak(struct ad714x_chip *ad714x, int idx)
+{
+	struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
+	struct ad714x_touchpad_drv *sw = &ad714x->sw->touchpad[idx];
+	int i;
+
+	for (i = hw->x_start_stage; i < sw->x_highest_stage; i++) {
+		if ((ad714x->sensor_val[i] - ad714x->sensor_val[i + 1])
+			> (ad714x->sensor_val[i + 1] / 10))
+			return 1;
+	}
+
+	for (i = sw->x_highest_stage; i < hw->x_end_stage; i++) {
+		if ((ad714x->sensor_val[i + 1] - ad714x->sensor_val[i])
+			> (ad714x->sensor_val[i] / 10))
+			return 1;
+	}
+
+	for (i = hw->y_start_stage; i < sw->y_highest_stage; i++) {
+		if ((ad714x->sensor_val[i] - ad714x->sensor_val[i + 1])
+			> (ad714x->sensor_val[i + 1] / 10))
+			return 1;
+	}
+
+	for (i = sw->y_highest_stage; i < hw->y_end_stage; i++) {
+		if ((ad714x->sensor_val[i + 1] - ad714x->sensor_val[i])
+			> (ad714x->sensor_val[i] / 10))
+			return 1;
+	}
+
+	return 0;
+}
+
+/*
+ * If only one finger is used to activate the touch pad then only 1 peak will be
+ * registered in the distribution. This peak and the 2 adjacent sensors will be
+ * used in the calculation of the absolute position. This will prevent hand
+ * shadows to affect the absolute position calculation.
+ */
+static void touchpad_cal_abs_pos(struct ad714x_chip *ad714x, int idx)
+{
+	struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
+	struct ad714x_touchpad_drv *sw = &ad714x->sw->touchpad[idx];
+
+	sw->x_abs_pos = ad714x_cal_abs_pos(ad714x, hw->x_start_stage,
+			hw->x_end_stage, sw->x_highest_stage, hw->x_max_coord);
+	sw->y_abs_pos = ad714x_cal_abs_pos(ad714x, hw->y_start_stage,
+			hw->y_end_stage, sw->y_highest_stage, hw->y_max_coord);
+
+	dev_dbg(ad714x->dev, "touchpad %d absolute position:(%d, %d)\n", idx,
+			sw->x_abs_pos, sw->y_abs_pos);
+}
+
+static void touchpad_cal_flt_pos(struct ad714x_chip *ad714x, int idx)
+{
+	struct ad714x_touchpad_drv *sw = &ad714x->sw->touchpad[idx];
+
+	sw->x_flt_pos = (sw->x_flt_pos * (10 - 4) +
+			sw->x_abs_pos * 4)/10;
+	sw->y_flt_pos = (sw->y_flt_pos * (10 - 4) +
+			sw->y_abs_pos * 4)/10;
+
+	dev_dbg(ad714x->dev, "touchpad %d filter position:(%d, %d)\n",
+			idx, sw->x_flt_pos, sw->y_flt_pos);
+}
+
+/*
+ * To prevent distortion from showing in the absolute position, it is
+ * necessary to detect the end points. When endpoints are detected, the
+ * driver stops updating the status variables with absolute positions.
+ * End points are detected on the 4 edges of the touchpad sensor. The
+ * method to detect them is the same for all 4.
+ * To detect the end points, the firmware computes the difference in
+ * percent between the sensor on the edge and the adjacent one. The
+ * difference is calculated in percent in order to make the end point
+ * detection independent of the pressure.
+ */
+
+#define LEFT_END_POINT_DETECTION_LEVEL                  550
+#define RIGHT_END_POINT_DETECTION_LEVEL                 750
+#define LEFT_RIGHT_END_POINT_DEAVTIVALION_LEVEL         850
+#define TOP_END_POINT_DETECTION_LEVEL                   550
+#define BOTTOM_END_POINT_DETECTION_LEVEL                950
+#define TOP_BOTTOM_END_POINT_DEAVTIVALION_LEVEL         700
+static int touchpad_check_endpoint(struct ad714x_chip *ad714x, int idx)
+{
+	struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
+	struct ad714x_touchpad_drv *sw  = &ad714x->sw->touchpad[idx];
+	int percent_sensor_diff;
+
+	/* left endpoint detect */
+	percent_sensor_diff = (ad714x->sensor_val[hw->x_start_stage] -
+			ad714x->sensor_val[hw->x_start_stage + 1]) * 100 /
+			ad714x->sensor_val[hw->x_start_stage + 1];
+	if (!sw->left_ep) {
+		if (percent_sensor_diff >= LEFT_END_POINT_DETECTION_LEVEL)  {
+			sw->left_ep = 1;
+			sw->left_ep_val =
+				ad714x->sensor_val[hw->x_start_stage + 1];
+		}
+	} else {
+		if ((percent_sensor_diff < LEFT_END_POINT_DETECTION_LEVEL) &&
+		    (ad714x->sensor_val[hw->x_start_stage + 1] >
+		     LEFT_RIGHT_END_POINT_DEAVTIVALION_LEVEL + sw->left_ep_val))
+			sw->left_ep = 0;
+	}
+
+	/* right endpoint detect */
+	percent_sensor_diff = (ad714x->sensor_val[hw->x_end_stage] -
+			ad714x->sensor_val[hw->x_end_stage - 1]) * 100 /
+			ad714x->sensor_val[hw->x_end_stage - 1];
+	if (!sw->right_ep) {
+		if (percent_sensor_diff >= RIGHT_END_POINT_DETECTION_LEVEL)  {
+			sw->right_ep = 1;
+			sw->right_ep_val =
+				ad714x->sensor_val[hw->x_end_stage - 1];
+		}
+	} else {
+		if ((percent_sensor_diff < RIGHT_END_POINT_DETECTION_LEVEL) &&
+		(ad714x->sensor_val[hw->x_end_stage - 1] >
+		LEFT_RIGHT_END_POINT_DEAVTIVALION_LEVEL + sw->right_ep_val))
+			sw->right_ep = 0;
+	}
+
+	/* top endpoint detect */
+	percent_sensor_diff = (ad714x->sensor_val[hw->y_start_stage] -
+			ad714x->sensor_val[hw->y_start_stage + 1]) * 100 /
+			ad714x->sensor_val[hw->y_start_stage + 1];
+	if (!sw->top_ep) {
+		if (percent_sensor_diff >= TOP_END_POINT_DETECTION_LEVEL)  {
+			sw->top_ep = 1;
+			sw->top_ep_val =
+				ad714x->sensor_val[hw->y_start_stage + 1];
+		}
+	} else {
+		if ((percent_sensor_diff < TOP_END_POINT_DETECTION_LEVEL) &&
+		(ad714x->sensor_val[hw->y_start_stage + 1] >
+		TOP_BOTTOM_END_POINT_DEAVTIVALION_LEVEL + sw->top_ep_val))
+			sw->top_ep = 0;
+	}
+
+	/* bottom endpoint detect */
+	percent_sensor_diff = (ad714x->sensor_val[hw->y_end_stage] -
+		ad714x->sensor_val[hw->y_end_stage - 1]) * 100 /
+		ad714x->sensor_val[hw->y_end_stage - 1];
+	if (!sw->bottom_ep) {
+		if (percent_sensor_diff >= BOTTOM_END_POINT_DETECTION_LEVEL)  {
+			sw->bottom_ep = 1;
+			sw->bottom_ep_val =
+				ad714x->sensor_val[hw->y_end_stage - 1];
+		}
+	} else {
+		if ((percent_sensor_diff < BOTTOM_END_POINT_DETECTION_LEVEL) &&
+		(ad714x->sensor_val[hw->y_end_stage - 1] >
+		 TOP_BOTTOM_END_POINT_DEAVTIVALION_LEVEL + sw->bottom_ep_val))
+			sw->bottom_ep = 0;
+	}
+
+	return sw->left_ep || sw->right_ep || sw->top_ep || sw->bottom_ep;
+}
+
+static void touchpad_use_com_int(struct ad714x_chip *ad714x, int idx)
+{
+	struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
+
+	ad714x_use_com_int(ad714x, hw->x_start_stage, hw->x_end_stage);
+}
+
+static void touchpad_use_thr_int(struct ad714x_chip *ad714x, int idx)
+{
+	struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
+
+	ad714x_use_thr_int(ad714x, hw->x_start_stage, hw->x_end_stage);
+	ad714x_use_thr_int(ad714x, hw->y_start_stage, hw->y_end_stage);
+}
+
+static void ad714x_touchpad_state_machine(struct ad714x_chip *ad714x, int idx)
+{
+	struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
+	struct ad714x_touchpad_drv *sw = &ad714x->sw->touchpad[idx];
+	unsigned short h_state, c_state;
+	unsigned short mask;
+
+	mask = (((1 << (hw->x_end_stage + 1)) - 1) -
+		((1 << hw->x_start_stage) - 1)) +
+		(((1 << (hw->y_end_stage + 1)) - 1) -
+		((1 << hw->y_start_stage) - 1));
+
+	h_state = ad714x->h_state & mask;
+	c_state = ad714x->c_state & mask;
+
+	switch (sw->state) {
+	case IDLE:
+		if (h_state) {
+			sw->state = JITTER;
+			/* In End of Conversion interrupt mode, the AD714X
+			 * continuously generates hardware interrupts.
+			 */
+			touchpad_use_com_int(ad714x, idx);
+			dev_dbg(ad714x->dev, "touchpad %d touched\n", idx);
+		}
+		break;
+
+	case JITTER:
+		if (c_state == mask) {
+			touchpad_cal_sensor_val(ad714x, idx);
+			touchpad_cal_highest_stage(ad714x, idx);
+			if ((!touchpad_check_second_peak(ad714x, idx)) &&
+				(!touchpad_check_endpoint(ad714x, idx))) {
+				dev_dbg(ad714x->dev,
+					"touchpad%d, 2 fingers or endpoint\n",
+					idx);
+				touchpad_cal_abs_pos(ad714x, idx);
+				sw->x_flt_pos = sw->x_abs_pos;
+				sw->y_flt_pos = sw->y_abs_pos;
+				sw->state = ACTIVE;
+			}
+		}
+		break;
+
+	case ACTIVE:
+		if (c_state == mask) {
+			if (h_state) {
+				touchpad_cal_sensor_val(ad714x, idx);
+				touchpad_cal_highest_stage(ad714x, idx);
+				if ((!touchpad_check_second_peak(ad714x, idx))
+				  && (!touchpad_check_endpoint(ad714x, idx))) {
+					touchpad_cal_abs_pos(ad714x, idx);
+					touchpad_cal_flt_pos(ad714x, idx);
+					input_report_abs(sw->input, ABS_X,
+						sw->x_flt_pos);
+					input_report_abs(sw->input, ABS_Y,
+						sw->y_flt_pos);
+					input_report_key(sw->input, BTN_TOUCH,
+						1);
+				}
+			} else {
+				/* When the user lifts off the sensor, configure
+				 * the AD714X back to threshold interrupt mode.
+				 */
+				touchpad_use_thr_int(ad714x, idx);
+				sw->state = IDLE;
+				input_report_key(sw->input, BTN_TOUCH, 0);
+				dev_dbg(ad714x->dev, "touchpad %d released\n",
+					idx);
+			}
+			input_sync(sw->input);
+		}
+		break;
+
+	default:
+		break;
+	}
+}
+
+static int ad714x_hw_detect(struct ad714x_chip *ad714x)
+{
+	unsigned short data;
+
+	ad714x->read(ad714x, AD714X_PARTID_REG, &data, 1);
+	switch (data & 0xFFF0) {
+	case AD7142_PARTID:
+		ad714x->product = 0x7142;
+		ad714x->version = data & 0xF;
+		dev_info(ad714x->dev, "found AD7142 captouch, rev:%d\n",
+				ad714x->version);
+		return 0;
+
+	case AD7143_PARTID:
+		ad714x->product = 0x7143;
+		ad714x->version = data & 0xF;
+		dev_info(ad714x->dev, "found AD7143 captouch, rev:%d\n",
+				ad714x->version);
+		return 0;
+
+	case AD7147_PARTID:
+		ad714x->product = 0x7147;
+		ad714x->version = data & 0xF;
+		dev_info(ad714x->dev, "found AD7147(A) captouch, rev:%d\n",
+				ad714x->version);
+		return 0;
+
+	case AD7148_PARTID:
+		ad714x->product = 0x7148;
+		ad714x->version = data & 0xF;
+		dev_info(ad714x->dev, "found AD7148 captouch, rev:%d\n",
+				ad714x->version);
+		return 0;
+
+	default:
+		dev_err(ad714x->dev,
+			"fail to detect AD714X captouch, read ID is %04x\n",
+			data);
+		return -ENODEV;
+	}
+}
+
+static void ad714x_hw_init(struct ad714x_chip *ad714x)
+{
+	int i, j;
+	unsigned short reg_base;
+	unsigned short data;
+
+	/* configuration CDC and interrupts */
+
+	for (i = 0; i < STAGE_NUM; i++) {
+		reg_base = AD714X_STAGECFG_REG + i * STAGE_CFGREG_NUM;
+		for (j = 0; j < STAGE_CFGREG_NUM; j++)
+			ad714x->write(ad714x, reg_base + j,
+					ad714x->hw->stage_cfg_reg[i][j]);
+	}
+
+	for (i = 0; i < SYS_CFGREG_NUM; i++)
+		ad714x->write(ad714x, AD714X_SYSCFG_REG + i,
+			ad714x->hw->sys_cfg_reg[i]);
+	for (i = 0; i < SYS_CFGREG_NUM; i++)
+		ad714x->read(ad714x, AD714X_SYSCFG_REG + i, &data, 1);
+
+	ad714x->write(ad714x, AD714X_STG_CAL_EN_REG, 0xFFF);
+
+	/* clear all interrupts */
+	ad714x->read(ad714x, STG_LOW_INT_STA_REG, &ad714x->l_state, 3);
+}
+
+static irqreturn_t ad714x_interrupt_thread(int irq, void *data)
+{
+	struct ad714x_chip *ad714x = data;
+	int i;
+
+	guard(mutex)(&ad714x->mutex);
+
+	ad714x->read(ad714x, STG_LOW_INT_STA_REG, &ad714x->l_state, 3);
+
+	for (i = 0; i < ad714x->hw->button_num; i++)
+		ad714x_button_state_machine(ad714x, i);
+	for (i = 0; i < ad714x->hw->slider_num; i++)
+		ad714x_slider_state_machine(ad714x, i);
+	for (i = 0; i < ad714x->hw->wheel_num; i++)
+		ad714x_wheel_state_machine(ad714x, i);
+	for (i = 0; i < ad714x->hw->touchpad_num; i++)
+		ad714x_touchpad_state_machine(ad714x, i);
+
+	return IRQ_HANDLED;
+}
+
+struct ad714x_chip *ad714x_probe(struct device *dev, u16 bus_type, int irq,
+				 ad714x_read_t read, ad714x_write_t write)
+{
+	int i;
+	int error;
+	struct input_dev *input;
+
+	struct ad714x_platform_data *plat_data = dev_get_platdata(dev);
+	struct ad714x_chip *ad714x;
+	void *drv_mem;
+	unsigned long irqflags;
+
+	struct ad714x_button_drv *bt_drv;
+	struct ad714x_slider_drv *sd_drv;
+	struct ad714x_wheel_drv *wl_drv;
+	struct ad714x_touchpad_drv *tp_drv;
+
+
+	if (irq <= 0) {
+		dev_err(dev, "IRQ not configured!\n");
+		error = -EINVAL;
+		return ERR_PTR(error);
+	}
+
+	if (dev_get_platdata(dev) == NULL) {
+		dev_err(dev, "platform data for ad714x doesn't exist\n");
+		error = -EINVAL;
+		return ERR_PTR(error);
+	}
+
+	ad714x = devm_kzalloc(dev, sizeof(*ad714x) + sizeof(*ad714x->sw) +
+				   sizeof(*sd_drv) * plat_data->slider_num +
+				   sizeof(*wl_drv) * plat_data->wheel_num +
+				   sizeof(*tp_drv) * plat_data->touchpad_num +
+				   sizeof(*bt_drv) * plat_data->button_num,
+			      GFP_KERNEL);
+	if (!ad714x) {
+		error = -ENOMEM;
+		return ERR_PTR(error);
+	}
+	ad714x->hw = plat_data;
+
+	drv_mem = ad714x + 1;
+	ad714x->sw = drv_mem;
+	drv_mem += sizeof(*ad714x->sw);
+	ad714x->sw->slider = sd_drv = drv_mem;
+	drv_mem += sizeof(*sd_drv) * ad714x->hw->slider_num;
+	ad714x->sw->wheel = wl_drv = drv_mem;
+	drv_mem += sizeof(*wl_drv) * ad714x->hw->wheel_num;
+	ad714x->sw->touchpad = tp_drv = drv_mem;
+	drv_mem += sizeof(*tp_drv) * ad714x->hw->touchpad_num;
+	ad714x->sw->button = bt_drv = drv_mem;
+	drv_mem += sizeof(*bt_drv) * ad714x->hw->button_num;
+
+	ad714x->read = read;
+	ad714x->write = write;
+	ad714x->irq = irq;
+	ad714x->dev = dev;
+
+	error = ad714x_hw_detect(ad714x);
+	if (error)
+		return ERR_PTR(error);
+
+	/* initialize and request sw/hw resources */
+
+	ad714x_hw_init(ad714x);
+	mutex_init(&ad714x->mutex);
+
+	/* a slider uses one input_dev instance */
+	if (ad714x->hw->slider_num > 0) {
+		struct ad714x_slider_plat *sd_plat = ad714x->hw->slider;
+
+		for (i = 0; i < ad714x->hw->slider_num; i++) {
+			input = devm_input_allocate_device(dev);
+			if (!input)
+				return ERR_PTR(-ENOMEM);
+
+			__set_bit(EV_ABS, input->evbit);
+			__set_bit(EV_KEY, input->evbit);
+			__set_bit(ABS_X, input->absbit);
+			__set_bit(BTN_TOUCH, input->keybit);
+			input_set_abs_params(input,
+				ABS_X, 0, sd_plat->max_coord, 0, 0);
+
+			input->id.bustype = bus_type;
+			input->id.product = ad714x->product;
+			input->id.version = ad714x->version;
+			input->name = "ad714x_captouch_slider";
+			input->dev.parent = dev;
+
+			error = input_register_device(input);
+			if (error)
+				return ERR_PTR(error);
+
+			sd_drv[i].input = input;
+		}
+	}
+
+	/* a wheel uses one input_dev instance */
+	if (ad714x->hw->wheel_num > 0) {
+		struct ad714x_wheel_plat *wl_plat = ad714x->hw->wheel;
+
+		for (i = 0; i < ad714x->hw->wheel_num; i++) {
+			input = devm_input_allocate_device(dev);
+			if (!input)
+				return ERR_PTR(-ENOMEM);
+
+			__set_bit(EV_KEY, input->evbit);
+			__set_bit(EV_ABS, input->evbit);
+			__set_bit(ABS_WHEEL, input->absbit);
+			__set_bit(BTN_TOUCH, input->keybit);
+			input_set_abs_params(input,
+				ABS_WHEEL, 0, wl_plat->max_coord, 0, 0);
+
+			input->id.bustype = bus_type;
+			input->id.product = ad714x->product;
+			input->id.version = ad714x->version;
+			input->name = "ad714x_captouch_wheel";
+			input->dev.parent = dev;
+
+			error = input_register_device(input);
+			if (error)
+				return ERR_PTR(error);
+
+			wl_drv[i].input = input;
+		}
+	}
+
+	/* a touchpad uses one input_dev instance */
+	if (ad714x->hw->touchpad_num > 0) {
+		struct ad714x_touchpad_plat *tp_plat = ad714x->hw->touchpad;
+
+		for (i = 0; i < ad714x->hw->touchpad_num; i++) {
+			input = devm_input_allocate_device(dev);
+			if (!input)
+				return ERR_PTR(-ENOMEM);
+
+			__set_bit(EV_ABS, input->evbit);
+			__set_bit(EV_KEY, input->evbit);
+			__set_bit(ABS_X, input->absbit);
+			__set_bit(ABS_Y, input->absbit);
+			__set_bit(BTN_TOUCH, input->keybit);
+			input_set_abs_params(input,
+				ABS_X, 0, tp_plat->x_max_coord, 0, 0);
+			input_set_abs_params(input,
+				ABS_Y, 0, tp_plat->y_max_coord, 0, 0);
+
+			input->id.bustype = bus_type;
+			input->id.product = ad714x->product;
+			input->id.version = ad714x->version;
+			input->name = "ad714x_captouch_pad";
+			input->dev.parent = dev;
+
+			error = input_register_device(input);
+			if (error)
+				return ERR_PTR(error);
+
+			tp_drv[i].input = input;
+		}
+	}
+
+	/* all buttons use one input node */
+	if (ad714x->hw->button_num > 0) {
+		struct ad714x_button_plat *bt_plat = ad714x->hw->button;
+
+		input = devm_input_allocate_device(dev);
+		if (!input) {
+			error = -ENOMEM;
+			return ERR_PTR(error);
+		}
+
+		__set_bit(EV_KEY, input->evbit);
+		for (i = 0; i < ad714x->hw->button_num; i++) {
+			bt_drv[i].input = input;
+			__set_bit(bt_plat[i].keycode, input->keybit);
+		}
+
+		input->id.bustype = bus_type;
+		input->id.product = ad714x->product;
+		input->id.version = ad714x->version;
+		input->name = "ad714x_captouch_button";
+		input->dev.parent = dev;
+
+		error = input_register_device(input);
+		if (error)
+			return ERR_PTR(error);
+	}
+
+	irqflags = plat_data->irqflags ?: IRQF_TRIGGER_FALLING;
+	irqflags |= IRQF_ONESHOT;
+
+	error = devm_request_threaded_irq(dev, ad714x->irq, NULL,
+					  ad714x_interrupt_thread,
+					  irqflags, "ad714x_captouch", ad714x);
+	if (error) {
+		dev_err(dev, "can't allocate irq %d\n", ad714x->irq);
+		return ERR_PTR(error);
+	}
+
+	return ad714x;
+}
+EXPORT_SYMBOL(ad714x_probe);
+
+static int ad714x_suspend(struct device *dev)
+{
+	struct ad714x_chip *ad714x = dev_get_drvdata(dev);
+	unsigned short data;
+
+	dev_dbg(ad714x->dev, "%s enter\n", __func__);
+
+	guard(mutex)(&ad714x->mutex);
+
+	data = ad714x->hw->sys_cfg_reg[AD714X_PWR_CTRL] | 0x3;
+	ad714x->write(ad714x, AD714X_PWR_CTRL, data);
+
+	return 0;
+}
+
+static int ad714x_resume(struct device *dev)
+{
+	struct ad714x_chip *ad714x = dev_get_drvdata(dev);
+	dev_dbg(ad714x->dev, "%s enter\n", __func__);
+
+	guard(mutex)(&ad714x->mutex);
+
+	/* resume to non-shutdown mode */
+
+	ad714x->write(ad714x, AD714X_PWR_CTRL,
+			ad714x->hw->sys_cfg_reg[AD714X_PWR_CTRL]);
+
+	/* make sure the interrupt output line is not low level after resume,
+	 * otherwise we will get no chance to enter falling-edge irq again
+	 */
+
+	ad714x->read(ad714x, STG_LOW_INT_STA_REG, &ad714x->l_state, 3);
+
+	return 0;
+}
+
+EXPORT_SIMPLE_DEV_PM_OPS(ad714x_pm, ad714x_suspend, ad714x_resume);
+
+MODULE_DESCRIPTION("Analog Devices AD714X Capacitance Touch Sensor Driver");
+MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
+MODULE_LICENSE("GPL");