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// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) ST-Ericsson SA 2010
* Author: Naveen Kumar G <naveen.gaddipati@stericsson.com> for ST-Ericsson
*/
#include <linux/bitops.h>
#include <linux/delay.h>
#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/input.h>
#include <linux/input/mt.h>
#include <linux/input/touchscreen.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/property.h>
#include <linux/regulator/consumer.h>
#include <linux/slab.h>
#include <linux/types.h>
#define MAX_FINGERS 2
#define RESET_DELAY 30
#define PENUP_TIMEOUT (10)
#define DELTA_MIN 16
#define MASK_BITS 0x03
#define SHIFT_8 8
#define SHIFT_2 2
#define LENGTH_OF_BUFFER 11
#define I2C_RETRY_COUNT 5
#define BU21013_SENSORS_BTN_0_7_REG 0x70
#define BU21013_SENSORS_BTN_8_15_REG 0x71
#define BU21013_SENSORS_BTN_16_23_REG 0x72
#define BU21013_X1_POS_MSB_REG 0x73
#define BU21013_X1_POS_LSB_REG 0x74
#define BU21013_Y1_POS_MSB_REG 0x75
#define BU21013_Y1_POS_LSB_REG 0x76
#define BU21013_X2_POS_MSB_REG 0x77
#define BU21013_X2_POS_LSB_REG 0x78
#define BU21013_Y2_POS_MSB_REG 0x79
#define BU21013_Y2_POS_LSB_REG 0x7A
#define BU21013_INT_CLR_REG 0xE8
#define BU21013_INT_MODE_REG 0xE9
#define BU21013_GAIN_REG 0xEA
#define BU21013_OFFSET_MODE_REG 0xEB
#define BU21013_XY_EDGE_REG 0xEC
#define BU21013_RESET_REG 0xED
#define BU21013_CALIB_REG 0xEE
#define BU21013_DONE_REG 0xEF
#define BU21013_SENSOR_0_7_REG 0xF0
#define BU21013_SENSOR_8_15_REG 0xF1
#define BU21013_SENSOR_16_23_REG 0xF2
#define BU21013_POS_MODE1_REG 0xF3
#define BU21013_POS_MODE2_REG 0xF4
#define BU21013_CLK_MODE_REG 0xF5
#define BU21013_IDLE_REG 0xFA
#define BU21013_FILTER_REG 0xFB
#define BU21013_TH_ON_REG 0xFC
#define BU21013_TH_OFF_REG 0xFD
#define BU21013_RESET_ENABLE 0x01
#define BU21013_SENSORS_EN_0_7 0x3F
#define BU21013_SENSORS_EN_8_15 0xFC
#define BU21013_SENSORS_EN_16_23 0x1F
#define BU21013_POS_MODE1_0 0x02
#define BU21013_POS_MODE1_1 0x04
#define BU21013_POS_MODE1_2 0x08
#define BU21013_POS_MODE2_ZERO 0x01
#define BU21013_POS_MODE2_AVG1 0x02
#define BU21013_POS_MODE2_AVG2 0x04
#define BU21013_POS_MODE2_EN_XY 0x08
#define BU21013_POS_MODE2_EN_RAW 0x10
#define BU21013_POS_MODE2_MULTI 0x80
#define BU21013_CLK_MODE_DIV 0x01
#define BU21013_CLK_MODE_EXT 0x02
#define BU21013_CLK_MODE_CALIB 0x80
#define BU21013_IDLET_0 0x01
#define BU21013_IDLET_1 0x02
#define BU21013_IDLET_2 0x04
#define BU21013_IDLET_3 0x08
#define BU21013_IDLE_INTERMIT_EN 0x10
#define BU21013_DELTA_0_6 0x7F
#define BU21013_FILTER_EN 0x80
#define BU21013_INT_MODE_LEVEL 0x00
#define BU21013_INT_MODE_EDGE 0x01
#define BU21013_GAIN_0 0x01
#define BU21013_GAIN_1 0x02
#define BU21013_GAIN_2 0x04
#define BU21013_OFFSET_MODE_DEFAULT 0x00
#define BU21013_OFFSET_MODE_MOVE 0x01
#define BU21013_OFFSET_MODE_DISABLE 0x02
#define BU21013_TH_ON_0 0x01
#define BU21013_TH_ON_1 0x02
#define BU21013_TH_ON_2 0x04
#define BU21013_TH_ON_3 0x08
#define BU21013_TH_ON_4 0x10
#define BU21013_TH_ON_5 0x20
#define BU21013_TH_ON_6 0x40
#define BU21013_TH_ON_7 0x80
#define BU21013_TH_ON_MAX 0xFF
#define BU21013_TH_OFF_0 0x01
#define BU21013_TH_OFF_1 0x02
#define BU21013_TH_OFF_2 0x04
#define BU21013_TH_OFF_3 0x08
#define BU21013_TH_OFF_4 0x10
#define BU21013_TH_OFF_5 0x20
#define BU21013_TH_OFF_6 0x40
#define BU21013_TH_OFF_7 0x80
#define BU21013_TH_OFF_MAX 0xFF
#define BU21013_X_EDGE_0 0x01
#define BU21013_X_EDGE_1 0x02
#define BU21013_X_EDGE_2 0x04
#define BU21013_X_EDGE_3 0x08
#define BU21013_Y_EDGE_0 0x10
#define BU21013_Y_EDGE_1 0x20
#define BU21013_Y_EDGE_2 0x40
#define BU21013_Y_EDGE_3 0x80
#define BU21013_DONE 0x01
#define BU21013_NUMBER_OF_X_SENSORS (6)
#define BU21013_NUMBER_OF_Y_SENSORS (11)
#define DRIVER_TP "bu21013_tp"
/**
* struct bu21013_ts - touch panel data structure
* @client: pointer to the i2c client
* @in_dev: pointer to the input device structure
* @props: the device coordinate transformation properties
* @regulator: pointer to the Regulator used for touch screen
* @cs_gpiod: chip select GPIO line
* @int_gpiod: touch interrupt GPIO line
* @touch_x_max: maximum X coordinate reported by the device
* @touch_y_max: maximum Y coordinate reported by the device
* @x_flip: indicates that the driver should invert X coordinate before
* reporting
* @y_flip: indicates that the driver should invert Y coordinate before
* reporting
* @touch_stopped: touch stop flag
*
* Touch panel device data structure
*/
struct bu21013_ts {
struct i2c_client *client;
struct input_dev *in_dev;
struct touchscreen_properties props;
struct regulator *regulator;
struct gpio_desc *cs_gpiod;
struct gpio_desc *int_gpiod;
u32 touch_x_max;
u32 touch_y_max;
bool x_flip;
bool y_flip;
bool touch_stopped;
};
static int bu21013_read_block_data(struct bu21013_ts *ts, u8 *buf)
{
int ret, i;
for (i = 0; i < I2C_RETRY_COUNT; i++) {
ret = i2c_smbus_read_i2c_block_data(ts->client,
BU21013_SENSORS_BTN_0_7_REG,
LENGTH_OF_BUFFER, buf);
if (ret == LENGTH_OF_BUFFER)
return 0;
}
return -EINVAL;
}
static int bu21013_do_touch_report(struct bu21013_ts *ts)
{
struct input_dev *input = ts->in_dev;
struct input_mt_pos pos[MAX_FINGERS];
int slots[MAX_FINGERS];
u8 buf[LENGTH_OF_BUFFER];
bool has_x_sensors, has_y_sensors;
int finger_down_count = 0;
int i;
if (bu21013_read_block_data(ts, buf) < 0)
return -EINVAL;
has_x_sensors = hweight32(buf[0] & BU21013_SENSORS_EN_0_7);
has_y_sensors = hweight32(((buf[1] & BU21013_SENSORS_EN_8_15) |
((buf[2] & BU21013_SENSORS_EN_16_23) << SHIFT_8)) >> SHIFT_2);
if (!has_x_sensors || !has_y_sensors)
return 0;
for (i = 0; i < MAX_FINGERS; i++) {
const u8 *data = &buf[4 * i + 3];
unsigned int x, y;
x = data[0] << SHIFT_2 | (data[1] & MASK_BITS);
y = data[2] << SHIFT_2 | (data[3] & MASK_BITS);
if (x != 0 && y != 0)
touchscreen_set_mt_pos(&pos[finger_down_count++],
&ts->props, x, y);
}
if (finger_down_count == 2 &&
(abs(pos[0].x - pos[1].x) < DELTA_MIN ||
abs(pos[0].y - pos[1].y) < DELTA_MIN)) {
return 0;
}
input_mt_assign_slots(input, slots, pos, finger_down_count, DELTA_MIN);
for (i = 0; i < finger_down_count; i++) {
input_mt_slot(input, slots[i]);
input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
input_report_abs(input, ABS_MT_POSITION_X, pos[i].x);
input_report_abs(input, ABS_MT_POSITION_Y, pos[i].y);
}
input_mt_sync_frame(input);
input_sync(input);
return 0;
}
static irqreturn_t bu21013_gpio_irq(int irq, void *device_data)
{
struct bu21013_ts *ts = device_data;
int keep_polling;
int error;
do {
error = bu21013_do_touch_report(ts);
if (error) {
dev_err(&ts->client->dev, "%s failed\n", __func__);
break;
}
if (unlikely(ts->touch_stopped))
break;
keep_polling = ts->int_gpiod ?
gpiod_get_value(ts->int_gpiod) : false;
if (keep_polling)
usleep_range(2000, 2500);
} while (keep_polling);
return IRQ_HANDLED;
}
static int bu21013_init_chip(struct bu21013_ts *ts)
{
struct i2c_client *client = ts->client;
int error;
error = i2c_smbus_write_byte_data(client, BU21013_RESET_REG,
BU21013_RESET_ENABLE);
if (error) {
dev_err(&client->dev, "BU21013_RESET reg write failed\n");
return error;
}
msleep(RESET_DELAY);
error = i2c_smbus_write_byte_data(client, BU21013_SENSOR_0_7_REG,
BU21013_SENSORS_EN_0_7);
if (error) {
dev_err(&client->dev, "BU21013_SENSOR_0_7 reg write failed\n");
return error;
}
error = i2c_smbus_write_byte_data(client, BU21013_SENSOR_8_15_REG,
BU21013_SENSORS_EN_8_15);
if (error) {
dev_err(&client->dev, "BU21013_SENSOR_8_15 reg write failed\n");
return error;
}
error = i2c_smbus_write_byte_data(client, BU21013_SENSOR_16_23_REG,
BU21013_SENSORS_EN_16_23);
if (error) {
dev_err(&client->dev, "BU21013_SENSOR_16_23 reg write failed\n");
return error;
}
error = i2c_smbus_write_byte_data(client, BU21013_POS_MODE1_REG,
BU21013_POS_MODE1_0 |
BU21013_POS_MODE1_1);
if (error) {
dev_err(&client->dev, "BU21013_POS_MODE1 reg write failed\n");
return error;
}
error = i2c_smbus_write_byte_data(client, BU21013_POS_MODE2_REG,
BU21013_POS_MODE2_ZERO |
BU21013_POS_MODE2_AVG1 |
BU21013_POS_MODE2_AVG2 |
BU21013_POS_MODE2_EN_RAW |
BU21013_POS_MODE2_MULTI);
if (error) {
dev_err(&client->dev, "BU21013_POS_MODE2 reg write failed\n");
return error;
}
error = i2c_smbus_write_byte_data(client, BU21013_CLK_MODE_REG,
BU21013_CLK_MODE_DIV |
BU21013_CLK_MODE_CALIB);
if (error) {
dev_err(&client->dev, "BU21013_CLK_MODE reg write failed\n");
return error;
}
error = i2c_smbus_write_byte_data(client, BU21013_IDLE_REG,
BU21013_IDLET_0 |
BU21013_IDLE_INTERMIT_EN);
if (error) {
dev_err(&client->dev, "BU21013_IDLE reg write failed\n");
return error;
}
error = i2c_smbus_write_byte_data(client, BU21013_INT_MODE_REG,
BU21013_INT_MODE_LEVEL);
if (error) {
dev_err(&client->dev, "BU21013_INT_MODE reg write failed\n");
return error;
}
error = i2c_smbus_write_byte_data(client, BU21013_FILTER_REG,
BU21013_DELTA_0_6 |
BU21013_FILTER_EN);
if (error) {
dev_err(&client->dev, "BU21013_FILTER reg write failed\n");
return error;
}
error = i2c_smbus_write_byte_data(client, BU21013_TH_ON_REG,
BU21013_TH_ON_5);
if (error) {
dev_err(&client->dev, "BU21013_TH_ON reg write failed\n");
return error;
}
error = i2c_smbus_write_byte_data(client, BU21013_TH_OFF_REG,
BU21013_TH_OFF_4 | BU21013_TH_OFF_3);
if (error) {
dev_err(&client->dev, "BU21013_TH_OFF reg write failed\n");
return error;
}
error = i2c_smbus_write_byte_data(client, BU21013_GAIN_REG,
BU21013_GAIN_0 | BU21013_GAIN_1);
if (error) {
dev_err(&client->dev, "BU21013_GAIN reg write failed\n");
return error;
}
error = i2c_smbus_write_byte_data(client, BU21013_OFFSET_MODE_REG,
BU21013_OFFSET_MODE_DEFAULT);
if (error) {
dev_err(&client->dev, "BU21013_OFFSET_MODE reg write failed\n");
return error;
}
error = i2c_smbus_write_byte_data(client, BU21013_XY_EDGE_REG,
BU21013_X_EDGE_0 |
BU21013_X_EDGE_2 |
BU21013_Y_EDGE_1 |
BU21013_Y_EDGE_3);
if (error) {
dev_err(&client->dev, "BU21013_XY_EDGE reg write failed\n");
return error;
}
error = i2c_smbus_write_byte_data(client, BU21013_DONE_REG,
BU21013_DONE);
if (error) {
dev_err(&client->dev, "BU21013_REG_DONE reg write failed\n");
return error;
}
return 0;
}
static void bu21013_power_off(void *_ts)
{
struct bu21013_ts *ts = _ts;
regulator_disable(ts->regulator);
}
static void bu21013_disable_chip(void *_ts)
{
struct bu21013_ts *ts = _ts;
gpiod_set_value(ts->cs_gpiod, 0);
}
static int bu21013_probe(struct i2c_client *client)
{
struct bu21013_ts *ts;
struct input_dev *in_dev;
struct input_absinfo *info;
u32 max_x = 0, max_y = 0;
int error;
if (!i2c_check_functionality(client->adapter,
I2C_FUNC_SMBUS_BYTE_DATA)) {
dev_err(&client->dev, "i2c smbus byte data not supported\n");
return -EIO;
}
if (!client->irq) {
dev_err(&client->dev, "No IRQ set up\n");
return -EINVAL;
}
ts = devm_kzalloc(&client->dev, sizeof(*ts), GFP_KERNEL);
if (!ts)
return -ENOMEM;
ts->client = client;
ts->x_flip = device_property_read_bool(&client->dev, "rohm,flip-x");
ts->y_flip = device_property_read_bool(&client->dev, "rohm,flip-y");
in_dev = devm_input_allocate_device(&client->dev);
if (!in_dev) {
dev_err(&client->dev, "device memory alloc failed\n");
return -ENOMEM;
}
ts->in_dev = in_dev;
input_set_drvdata(in_dev, ts);
/* register the device to input subsystem */
in_dev->name = DRIVER_TP;
in_dev->id.bustype = BUS_I2C;
device_property_read_u32(&client->dev, "rohm,touch-max-x", &max_x);
device_property_read_u32(&client->dev, "rohm,touch-max-y", &max_y);
input_set_abs_params(in_dev, ABS_MT_POSITION_X, 0, max_x, 0, 0);
input_set_abs_params(in_dev, ABS_MT_POSITION_Y, 0, max_y, 0, 0);
touchscreen_parse_properties(in_dev, true, &ts->props);
/* Adjust for the legacy "flip" properties, if present */
if (!ts->props.invert_x &&
device_property_read_bool(&client->dev, "rohm,flip-x")) {
info = &in_dev->absinfo[ABS_MT_POSITION_X];
info->maximum -= info->minimum;
info->minimum = 0;
}
if (!ts->props.invert_y &&
device_property_read_bool(&client->dev, "rohm,flip-y")) {
info = &in_dev->absinfo[ABS_MT_POSITION_Y];
info->maximum -= info->minimum;
info->minimum = 0;
}
error = input_mt_init_slots(in_dev, MAX_FINGERS,
INPUT_MT_DIRECT | INPUT_MT_TRACK |
INPUT_MT_DROP_UNUSED);
if (error) {
dev_err(&client->dev, "failed to initialize MT slots");
return error;
}
ts->regulator = devm_regulator_get(&client->dev, "avdd");
if (IS_ERR(ts->regulator)) {
dev_err(&client->dev, "regulator_get failed\n");
return PTR_ERR(ts->regulator);
}
error = regulator_enable(ts->regulator);
if (error) {
dev_err(&client->dev, "regulator enable failed\n");
return error;
}
error = devm_add_action_or_reset(&client->dev, bu21013_power_off, ts);
if (error) {
dev_err(&client->dev, "failed to install power off handler\n");
return error;
}
/* Named "CS" on the chip, DT binding is "reset" */
ts->cs_gpiod = devm_gpiod_get(&client->dev, "reset", GPIOD_OUT_HIGH);
error = PTR_ERR_OR_ZERO(ts->cs_gpiod);
if (error) {
if (error != -EPROBE_DEFER)
dev_err(&client->dev, "failed to get CS GPIO\n");
return error;
}
gpiod_set_consumer_name(ts->cs_gpiod, "BU21013 CS");
error = devm_add_action_or_reset(&client->dev,
bu21013_disable_chip, ts);
if (error) {
dev_err(&client->dev,
"failed to install chip disable handler\n");
return error;
}
/* Named "INT" on the chip, DT binding is "touch" */
ts->int_gpiod = devm_gpiod_get_optional(&client->dev,
"touch", GPIOD_IN);
error = PTR_ERR_OR_ZERO(ts->int_gpiod);
if (error) {
if (error != -EPROBE_DEFER)
dev_err(&client->dev, "failed to get INT GPIO\n");
return error;
}
if (ts->int_gpiod)
gpiod_set_consumer_name(ts->int_gpiod, "BU21013 INT");
/* configure the touch panel controller */
error = bu21013_init_chip(ts);
if (error) {
dev_err(&client->dev, "error in bu21013 config\n");
return error;
}
error = devm_request_threaded_irq(&client->dev, client->irq,
NULL, bu21013_gpio_irq,
IRQF_ONESHOT, DRIVER_TP, ts);
if (error) {
dev_err(&client->dev, "request irq %d failed\n",
client->irq);
return error;
}
error = input_register_device(in_dev);
if (error) {
dev_err(&client->dev, "failed to register input device\n");
return error;
}
i2c_set_clientdata(client, ts);
return 0;
}
static void bu21013_remove(struct i2c_client *client)
{
struct bu21013_ts *ts = i2c_get_clientdata(client);
/* Make sure IRQ will exit quickly even if there is contact */
ts->touch_stopped = true;
/* The resources will be freed by devm */
}
static int __maybe_unused bu21013_suspend(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct bu21013_ts *ts = i2c_get_clientdata(client);
ts->touch_stopped = true;
mb();
disable_irq(client->irq);
if (!device_may_wakeup(&client->dev))
regulator_disable(ts->regulator);
return 0;
}
static int __maybe_unused bu21013_resume(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct bu21013_ts *ts = i2c_get_clientdata(client);
int error;
if (!device_may_wakeup(&client->dev)) {
error = regulator_enable(ts->regulator);
if (error) {
dev_err(&client->dev,
"failed to re-enable regulator when resuming\n");
return error;
}
error = bu21013_init_chip(ts);
if (error) {
dev_err(&client->dev,
"failed to reinitialize chip when resuming\n");
return error;
}
}
ts->touch_stopped = false;
mb();
enable_irq(client->irq);
return 0;
}
static SIMPLE_DEV_PM_OPS(bu21013_dev_pm_ops, bu21013_suspend, bu21013_resume);
static const struct i2c_device_id bu21013_id[] = {
{ DRIVER_TP, 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, bu21013_id);
static struct i2c_driver bu21013_driver = {
.driver = {
.name = DRIVER_TP,
.pm = &bu21013_dev_pm_ops,
},
.probe_new = bu21013_probe,
.remove = bu21013_remove,
.id_table = bu21013_id,
};
module_i2c_driver(bu21013_driver);
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Naveen Kumar G <naveen.gaddipati@stericsson.com>");
MODULE_DESCRIPTION("bu21013 touch screen controller driver");
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