// SPDX-License-Identifier: GPL-2.0+
/*
* Driver for ChipOne icn8505 i2c touchscreen controller
*
* Copyright (c) 2015-2018 Red Hat Inc.
*
* Red Hat authors:
* Hans de Goede <[email protected]>
*/
#include <linux/unaligned.h>
#include <linux/acpi.h>
#include <linux/crc32.h>
#include <linux/delay.h>
#include <linux/firmware.h>
#include <linux/interrupt.h>
#include <linux/i2c.h>
#include <linux/input.h>
#include <linux/input/mt.h>
#include <linux/input/touchscreen.h>
#include <linux/module.h>
/* Normal operation mode defines */
#define ICN8505_REG_ADDR_WIDTH 16
#define ICN8505_REG_POWER 0x0004
#define ICN8505_REG_TOUCHDATA 0x1000
#define ICN8505_REG_CONFIGDATA 0x8000
/* ICN8505_REG_POWER commands */
#define ICN8505_POWER_ACTIVE 0x00
#define ICN8505_POWER_MONITOR 0x01
#define ICN8505_POWER_HIBERNATE 0x02
/*
* The Android driver uses these to turn on/off the charger filter, but the
* filter is way too aggressive making e.g. onscreen keyboards unusable.
*/
#define ICN8505_POWER_ENA_CHARGER_MODE 0x55
#define ICN8505_POWER_DIS_CHARGER_MODE 0x66
#define ICN8505_MAX_TOUCHES 10
/* Programming mode defines */
#define ICN8505_PROG_I2C_ADDR 0x30
#define ICN8505_PROG_REG_ADDR_WIDTH 24
#define MAX_FW_UPLOAD_TRIES 3
struct icn8505_touch {
u8 slot;
u8 x[2];
u8 y[2];
u8 pressure; /* Seems more like finger width then pressure really */
u8 event;
/* The difference between 2 and 3 is unclear */
#define ICN8505_EVENT_NO_DATA 1 /* No finger seen yet since wakeup */
#define ICN8505_EVENT_UPDATE1 2 /* New or updated coordinates */
#define ICN8505_EVENT_UPDATE2 3 /* New or updated coordinates */
#define ICN8505_EVENT_END 4 /* Finger lifted */
} __packed;
struct icn8505_touch_data {
u8 softbutton;
u8 touch_count;
struct icn8505_touch touches[ICN8505_MAX_TOUCHES];
} __packed;
struct icn8505_data {
struct i2c_client *client;
struct input_dev *input;
struct touchscreen_properties prop;
char firmware_name[32];
};
static int icn8505_read_xfer(struct i2c_client *client, u16 i2c_addr,
int reg_addr, int reg_addr_width,
void *data, int len, bool silent)
{
u8 buf[3];
int i, ret;
struct i2c_msg msg[2] = {
{
.addr = i2c_addr,
.buf = buf,
.len = reg_addr_width / 8,
},
{
.addr = i2c_addr,
.flags = I2C_M_RD,
.buf = data,
.len = len,
}
};
for (i = 0; i < (reg_addr_width / 8); i++)
buf[i] = (reg_addr >> (reg_addr_width - (i + 1) * 8)) & 0xff;
ret = i2c_transfer(client->adapter, msg, 2);
if (ret != ARRAY_SIZE(msg)) {
if (ret >= 0)
ret = -EIO;
if (!silent)
dev_err(&client->dev,
"Error reading addr %#x reg %#x: %d\n",
i2c_addr, reg_addr, ret);
return ret;
}
return 0;
}
static int icn8505_write_xfer(struct i2c_client *client, u16 i2c_addr,
int reg_addr, int reg_addr_width,
const void *data, int len, bool silent)
{
u8 buf[3 + 32]; /* 3 bytes for 24 bit reg-addr + 32 bytes max len */
int i, ret;
struct i2c_msg msg = {
.addr = i2c_addr,
.buf = buf,
.len = reg_addr_width / 8 + len,
};
if (WARN_ON(len > 32))
return -EINVAL;
for (i = 0; i < (reg_addr_width / 8); i++)
buf[i] = (reg_addr >> (reg_addr_width - (i + 1) * 8)) & 0xff;
memcpy(buf + reg_addr_width / 8, data, len);
ret = i2c_transfer(client->adapter, &msg, 1);
if (ret != 1) {
if (ret >= 0)
ret = -EIO;
if (!silent)
dev_err(&client->dev,
"Error writing addr %#x reg %#x: %d\n",
i2c_addr, reg_addr, ret);
return ret;
}
return 0;
}
static int icn8505_read_data(struct icn8505_data *icn8505, int reg,
void *buf, int len)
{
return icn8505_read_xfer(icn8505->client, icn8505->client->addr, reg,
ICN8505_REG_ADDR_WIDTH, buf, len, false);
}
static int icn8505_read_reg_silent(struct icn8505_data *icn8505, int reg)
{
u8 buf;
int error;
error = icn8505_read_xfer(icn8505->client, icn8505->client->addr, reg,
ICN8505_REG_ADDR_WIDTH, &buf, 1, true);
if (error)
return error;
return buf;
}
static int icn8505_write_reg(struct icn8505_data *icn8505, int reg, u8 val)
{
return icn8505_write_xfer(icn8505->client, icn8505->client->addr, reg,
ICN8505_REG_ADDR_WIDTH, &val, 1, false);
}
static int icn8505_read_prog_data(struct icn8505_data *icn8505, int reg,
void *buf, int len)
{
return icn8505_read_xfer(icn8505->client, ICN8505_PROG_I2C_ADDR, reg,
ICN8505_PROG_REG_ADDR_WIDTH, buf, len, false);
}
static int icn8505_write_prog_data(struct icn8505_data *icn8505, int reg,
const void *buf, int len)
{
return icn8505_write_xfer(icn8505->client, ICN8505_PROG_I2C_ADDR, reg,
ICN8505_PROG_REG_ADDR_WIDTH, buf, len, false);
}
static int icn8505_write_prog_reg(struct icn8505_data *icn8505, int reg, u8 val)
{
return icn8505_write_xfer(icn8505->client, ICN8505_PROG_I2C_ADDR, reg,
ICN8505_PROG_REG_ADDR_WIDTH, &val, 1, false);
}
/*
* Note this function uses a number of magic register addresses and values,
* there are deliberately no defines for these because the algorithm is taken
* from the icn85xx Android driver and I do not want to make up possibly wrong
* names for the addresses and/or values.
*/
static int icn8505_try_fw_upload(struct icn8505_data *icn8505,
const struct firmware *fw)
{
struct device *dev = &icn8505->client->dev;
size_t offset, count;
int error;
u8 buf[4];
u32 crc;
/* Put the controller in programming mode */
error = icn8505_write_prog_reg(icn8505, 0xcc3355, 0x5a);
if (error)
return error;
usleep_range(2000, 5000);
error = icn8505_write_prog_reg(icn8505, 0x040400, 0x01);
if (error)
return error;
usleep_range(2000, 5000);
error = icn8505_read_prog_data(icn8505, 0x040002, buf, 1);
if (error)
return error;
if (buf[0] != 0x85) {
dev_err(dev, "Failed to enter programming mode\n");
return -ENODEV;
}
usleep_range(1000, 5000);
/* Enable CRC mode */
error = icn8505_write_prog_reg(icn8505, 0x40028, 1);
if (error)
return error;
/* Send the firmware to SRAM */
for (offset = 0; offset < fw->size; offset += count) {
count = min_t(size_t, fw->size - offset, 32);
error = icn8505_write_prog_data(icn8505, offset,
fw->data + offset, count);
if (error)
return error;
}
/* Disable CRC mode */
error = icn8505_write_prog_reg(icn8505, 0x40028, 0);
if (error)
return error;
/* Get and check length and CRC */
error = icn8505_read_prog_data(icn8505, 0x40034, buf, 2);
if (error)
return error;
if (get_unaligned_le16(buf) != fw->size) {
dev_warn(dev, "Length mismatch after uploading fw\n");
return -EIO;
}
error = icn8505_read_prog_data(icn8505, 0x4002c, buf, 4);
if (error)
return error;
crc = crc32_be(0, fw->data, fw->size);
if (get_unaligned_le32(buf) != crc) {
dev_warn(dev, "CRC mismatch after uploading fw\n");
return -EIO;
}
/* Boot controller from SRAM */
error = icn8505_write_prog_reg(icn8505, 0x40400, 0x03);
if (error)
return error;
usleep_range(2000, 5000);
return 0;
}
static int icn8505_upload_fw(struct icn8505_data *icn8505)
{
struct device *dev = &icn8505->client->dev;
const struct firmware *fw;
int i, error;
/*
* Always load the firmware, even if we don't need it at boot, we
* we may need it at resume. Having loaded it once will make the
* firmware class code cache it at suspend/resume.
*/
error = firmware_request_platform(&fw, icn8505->firmware_name, dev);
if (error) {
dev_err(dev, "Firmware request error %d\n", error);
return error;
}
/* Check if the controller is not already up and running */
if (icn8505_read_reg_silent(icn8505, 0x000a) == 0x85)
goto success;
for (i = 1; i <= MAX_FW_UPLOAD_TRIES; i++) {
error = icn8505_try_fw_upload(icn8505, fw);
if (!error)
goto success;
dev_err(dev, "Failed to upload firmware: %d (attempt %d/%d)\n",
error, i, MAX_FW_UPLOAD_TRIES);
usleep_range(2000, 5000);
}
success:
release_firmware(fw);
return error;
}
static bool icn8505_touch_active(u8 event)
{
return event == ICN8505_EVENT_UPDATE1 ||
event == ICN8505_EVENT_UPDATE2;
}
static irqreturn_t icn8505_irq(int irq, void *dev_id)
{
struct icn8505_data *icn8505 = dev_id;
struct device *dev = &icn8505->client->dev;
struct icn8505_touch_data touch_data;
int i, error;
error = icn8505_read_data(icn8505, ICN8505_REG_TOUCHDATA,
&touch_data, sizeof(touch_data));
if (error) {
dev_err(dev, "Error reading touch data: %d\n", error);
return IRQ_HANDLED;
}
if (touch_data.touch_count > ICN8505_MAX_TOUCHES) {
dev_warn(dev, "Too many touches %d > %d\n",
touch_data.touch_count, ICN8505_MAX_TOUCHES);
touch_data.touch_count = ICN8505_MAX_TOUCHES;
}
for (i = 0; i < touch_data.touch_count; i++) {
struct icn8505_touch *touch = &touch_data.touches[i];
bool act = icn8505_touch_active(touch->event);
input_mt_slot(icn8505->input, touch->slot);
input_mt_report_slot_state(icn8505->input, MT_TOOL_FINGER, act);
if (!act)
continue;
touchscreen_report_pos(icn8505->input, &icn8505->prop,
get_unaligned_le16(touch->x),
get_unaligned_le16(touch->y),
true);
}
input_mt_sync_frame(icn8505->input);
input_report_key(icn8505->input, KEY_LEFTMETA,
touch_data.softbutton == 1);
input_sync(icn8505->input);
return IRQ_HANDLED;
}
static int icn8505_probe_acpi(struct icn8505_data *icn8505, struct device *dev)
{
const char *subsys;
int error;
subsys = acpi_get_subsystem_id(ACPI_HANDLE(dev));
error = PTR_ERR_OR_ZERO(subsys);
if (error == -ENODATA)
subsys = "unknown";
else if (error)
return error;
snprintf(icn8505->firmware_name, sizeof(icn8505->firmware_name),
"chipone/icn8505-%s.fw", subsys);
kfree_const(subsys);
return 0;
}
static int icn8505_probe(struct i2c_client *client)
{
struct device *dev = &client->dev;
struct icn8505_data *icn8505;
struct input_dev *input;
__le16 resolution[2];
int error;
if (!client->irq) {
dev_err(dev, "No irq specified\n");
return -EINVAL;
}
icn8505 = devm_kzalloc(dev, sizeof(*icn8505), GFP_KERNEL);
if (!icn8505)
return -ENOMEM;
input = devm_input_allocate_device(dev);
if (!input)
return -ENOMEM;
input->name = client->name;
input->id.bustype = BUS_I2C;
input_set_capability(input, EV_ABS, ABS_MT_POSITION_X);
input_set_capability(input, EV_ABS, ABS_MT_POSITION_Y);
input_set_capability(input, EV_KEY, KEY_LEFTMETA);
icn8505->client = client;
icn8505->input = input;
input_set_drvdata(input, icn8505);
error = icn8505_probe_acpi(icn8505, dev);
if (error)
return error;
error = icn8505_upload_fw(icn8505);
if (error)
return error;
error = icn8505_read_data(icn8505, ICN8505_REG_CONFIGDATA,
resolution, sizeof(resolution));
if (error) {
dev_err(dev, "Error reading resolution: %d\n", error);
return error;
}
input_set_abs_params(input, ABS_MT_POSITION_X, 0,
le16_to_cpu(resolution[0]) - 1, 0, 0);
input_set_abs_params(input, ABS_MT_POSITION_Y, 0,
le16_to_cpu(resolution[1]) - 1, 0, 0);
touchscreen_parse_properties(input, true, &icn8505->prop);
if (!input_abs_get_max(input, ABS_MT_POSITION_X) ||
!input_abs_get_max(input, ABS_MT_POSITION_Y)) {
dev_err(dev, "Error touchscreen-size-x and/or -y missing\n");
return -EINVAL;
}
error = input_mt_init_slots(input, ICN8505_MAX_TOUCHES,
INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
if (error)
return error;
error = devm_request_threaded_irq(dev, client->irq, NULL, icn8505_irq,
IRQF_ONESHOT, client->name, icn8505);
if (error) {
dev_err(dev, "Error requesting irq: %d\n", error);
return error;
}
error = input_register_device(input);
if (error)
return error;
i2c_set_clientdata(client, icn8505);
return 0;
}
static int icn8505_suspend(struct device *dev)
{
struct icn8505_data *icn8505 = i2c_get_clientdata(to_i2c_client(dev));
disable_irq(icn8505->client->irq);
icn8505_write_reg(icn8505, ICN8505_REG_POWER, ICN8505_POWER_HIBERNATE);
return 0;
}
static int icn8505_resume(struct device *dev)
{
struct icn8505_data *icn8505 = i2c_get_clientdata(to_i2c_client(dev));
int error;
error = icn8505_upload_fw(icn8505);
if (error)
return error;
enable_irq(icn8505->client->irq);
return 0;
}
static DEFINE_SIMPLE_DEV_PM_OPS(icn8505_pm_ops, icn8505_suspend, icn8505_resume);
static const struct acpi_device_id icn8505_acpi_match[] = {
{ "CHPN0001" },
{ }
};
MODULE_DEVICE_TABLE(acpi, icn8505_acpi_match);
static struct i2c_driver icn8505_driver = {
.driver = {
.name = "chipone_icn8505",
.pm = pm_sleep_ptr(&icn8505_pm_ops),
.acpi_match_table = icn8505_acpi_match,
},
.probe = icn8505_probe,
};
module_i2c_driver(icn8505_driver);
MODULE_DESCRIPTION("ChipOne icn8505 I2C Touchscreen Driver");
MODULE_AUTHOR("Hans de Goede <[email protected]>");
MODULE_LICENSE("GPL");
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