diff options
Diffstat (limited to 'drivers/input/touchscreen/hycon-hy46xx.c')
-rw-r--r-- | drivers/input/touchscreen/hycon-hy46xx.c | 590 |
1 files changed, 590 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/hycon-hy46xx.c b/drivers/input/touchscreen/hycon-hy46xx.c new file mode 100644 index 0000000000..2450cfa14d --- /dev/null +++ b/drivers/input/touchscreen/hycon-hy46xx.c @@ -0,0 +1,590 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2021 + * Author(s): Giulio Benetti <giulio.benetti@benettiengineering.com> + */ + +#include <linux/delay.h> +#include <linux/gpio/consumer.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/input.h> +#include <linux/input/mt.h> +#include <linux/input/touchscreen.h> +#include <linux/irq.h> +#include <linux/regulator/consumer.h> +#include <linux/regmap.h> + +#include <asm/unaligned.h> + +#define HY46XX_CHKSUM_CODE 0x1 +#define HY46XX_FINGER_NUM 0x2 +#define HY46XX_CHKSUM_LEN 0x7 +#define HY46XX_THRESHOLD 0x80 +#define HY46XX_GLOVE_EN 0x84 +#define HY46XX_REPORT_SPEED 0x88 +#define HY46XX_PWR_NOISE_EN 0x89 +#define HY46XX_FILTER_DATA 0x8A +#define HY46XX_GAIN 0x92 +#define HY46XX_EDGE_OFFSET 0x93 +#define HY46XX_RX_NR_USED 0x94 +#define HY46XX_TX_NR_USED 0x95 +#define HY46XX_PWR_MODE 0xA5 +#define HY46XX_FW_VERSION 0xA6 +#define HY46XX_LIB_VERSION 0xA7 +#define HY46XX_TP_INFO 0xA8 +#define HY46XX_TP_CHIP_ID 0xA9 +#define HY46XX_BOOT_VER 0xB0 + +#define HY46XX_TPLEN 0x6 +#define HY46XX_REPORT_PKT_LEN 0x44 + +#define HY46XX_MAX_SUPPORTED_POINTS 11 + +#define TOUCH_EVENT_DOWN 0x00 +#define TOUCH_EVENT_UP 0x01 +#define TOUCH_EVENT_CONTACT 0x02 +#define TOUCH_EVENT_RESERVED 0x03 + +struct hycon_hy46xx_data { + struct i2c_client *client; + struct input_dev *input; + struct touchscreen_properties prop; + struct regulator *vcc; + + struct gpio_desc *reset_gpio; + + struct mutex mutex; + struct regmap *regmap; + + int threshold; + bool glove_enable; + int report_speed; + bool noise_filter_enable; + int filter_data; + int gain; + int edge_offset; + int rx_number_used; + int tx_number_used; + int power_mode; + int fw_version; + int lib_version; + int tp_information; + int tp_chip_id; + int bootloader_version; +}; + +static const struct regmap_config hycon_hy46xx_i2c_regmap_config = { + .reg_bits = 8, + .val_bits = 8, +}; + +static bool hycon_hy46xx_check_checksum(struct hycon_hy46xx_data *tsdata, u8 *buf) +{ + u8 chksum = 0; + int i; + + for (i = 2; i < buf[HY46XX_CHKSUM_LEN]; i++) + chksum += buf[i]; + + if (chksum == buf[HY46XX_CHKSUM_CODE]) + return true; + + dev_err_ratelimited(&tsdata->client->dev, + "checksum error: 0x%02x expected, got 0x%02x\n", + chksum, buf[HY46XX_CHKSUM_CODE]); + + return false; +} + +static irqreturn_t hycon_hy46xx_isr(int irq, void *dev_id) +{ + struct hycon_hy46xx_data *tsdata = dev_id; + struct device *dev = &tsdata->client->dev; + u8 rdbuf[HY46XX_REPORT_PKT_LEN]; + int i, x, y, id; + int error; + + memset(rdbuf, 0, sizeof(rdbuf)); + + error = regmap_bulk_read(tsdata->regmap, 0, rdbuf, sizeof(rdbuf)); + if (error) { + dev_err_ratelimited(dev, "Unable to fetch data, error: %d\n", + error); + goto out; + } + + if (!hycon_hy46xx_check_checksum(tsdata, rdbuf)) + goto out; + + for (i = 0; i < HY46XX_MAX_SUPPORTED_POINTS; i++) { + u8 *buf = &rdbuf[3 + (HY46XX_TPLEN * i)]; + int type = buf[0] >> 6; + + if (type == TOUCH_EVENT_RESERVED) + continue; + + x = get_unaligned_be16(buf) & 0x0fff; + y = get_unaligned_be16(buf + 2) & 0x0fff; + + id = buf[2] >> 4; + + input_mt_slot(tsdata->input, id); + if (input_mt_report_slot_state(tsdata->input, MT_TOOL_FINGER, + type != TOUCH_EVENT_UP)) + touchscreen_report_pos(tsdata->input, &tsdata->prop, + x, y, true); + } + + input_mt_report_pointer_emulation(tsdata->input, false); + input_sync(tsdata->input); + +out: + return IRQ_HANDLED; +} + +struct hycon_hy46xx_attribute { + struct device_attribute dattr; + size_t field_offset; + u8 address; + u8 limit_low; + u8 limit_high; +}; + +#define HYCON_ATTR_U8(_field, _mode, _address, _limit_low, _limit_high) \ + struct hycon_hy46xx_attribute hycon_hy46xx_attr_##_field = { \ + .dattr = __ATTR(_field, _mode, \ + hycon_hy46xx_setting_show, \ + hycon_hy46xx_setting_store), \ + .field_offset = offsetof(struct hycon_hy46xx_data, _field), \ + .address = _address, \ + .limit_low = _limit_low, \ + .limit_high = _limit_high, \ + } + +#define HYCON_ATTR_BOOL(_field, _mode, _address) \ + struct hycon_hy46xx_attribute hycon_hy46xx_attr_##_field = { \ + .dattr = __ATTR(_field, _mode, \ + hycon_hy46xx_setting_show, \ + hycon_hy46xx_setting_store), \ + .field_offset = offsetof(struct hycon_hy46xx_data, _field), \ + .address = _address, \ + .limit_low = false, \ + .limit_high = true, \ + } + +static ssize_t hycon_hy46xx_setting_show(struct device *dev, + struct device_attribute *dattr, char *buf) +{ + struct i2c_client *client = to_i2c_client(dev); + struct hycon_hy46xx_data *tsdata = i2c_get_clientdata(client); + struct hycon_hy46xx_attribute *attr = + container_of(dattr, struct hycon_hy46xx_attribute, dattr); + u8 *field = (u8 *)tsdata + attr->field_offset; + size_t count = 0; + int error = 0; + int val; + + mutex_lock(&tsdata->mutex); + + error = regmap_read(tsdata->regmap, attr->address, &val); + if (error < 0) { + dev_err(&tsdata->client->dev, + "Failed to fetch attribute %s, error %d\n", + dattr->attr.name, error); + goto out; + } + + if (val != *field) { + dev_warn(&tsdata->client->dev, + "%s: read (%d) and stored value (%d) differ\n", + dattr->attr.name, val, *field); + *field = val; + } + + count = scnprintf(buf, PAGE_SIZE, "%d\n", val); + +out: + mutex_unlock(&tsdata->mutex); + return error ?: count; +} + +static ssize_t hycon_hy46xx_setting_store(struct device *dev, + struct device_attribute *dattr, + const char *buf, size_t count) +{ + struct i2c_client *client = to_i2c_client(dev); + struct hycon_hy46xx_data *tsdata = i2c_get_clientdata(client); + struct hycon_hy46xx_attribute *attr = + container_of(dattr, struct hycon_hy46xx_attribute, dattr); + u8 *field = (u8 *)tsdata + attr->field_offset; + unsigned int val; + int error; + + mutex_lock(&tsdata->mutex); + + error = kstrtouint(buf, 0, &val); + if (error) + goto out; + + if (val < attr->limit_low || val > attr->limit_high) { + error = -ERANGE; + goto out; + } + + error = regmap_write(tsdata->regmap, attr->address, val); + if (error < 0) { + dev_err(&tsdata->client->dev, + "Failed to update attribute %s, error: %d\n", + dattr->attr.name, error); + goto out; + } + *field = val; + +out: + mutex_unlock(&tsdata->mutex); + return error ?: count; +} + +static HYCON_ATTR_U8(threshold, 0644, HY46XX_THRESHOLD, 0, 255); +static HYCON_ATTR_BOOL(glove_enable, 0644, HY46XX_GLOVE_EN); +static HYCON_ATTR_U8(report_speed, 0644, HY46XX_REPORT_SPEED, 0, 255); +static HYCON_ATTR_BOOL(noise_filter_enable, 0644, HY46XX_PWR_NOISE_EN); +static HYCON_ATTR_U8(filter_data, 0644, HY46XX_FILTER_DATA, 0, 5); +static HYCON_ATTR_U8(gain, 0644, HY46XX_GAIN, 0, 5); +static HYCON_ATTR_U8(edge_offset, 0644, HY46XX_EDGE_OFFSET, 0, 5); +static HYCON_ATTR_U8(fw_version, 0444, HY46XX_FW_VERSION, 0, 255); +static HYCON_ATTR_U8(lib_version, 0444, HY46XX_LIB_VERSION, 0, 255); +static HYCON_ATTR_U8(tp_information, 0444, HY46XX_TP_INFO, 0, 255); +static HYCON_ATTR_U8(tp_chip_id, 0444, HY46XX_TP_CHIP_ID, 0, 255); +static HYCON_ATTR_U8(bootloader_version, 0444, HY46XX_BOOT_VER, 0, 255); + +static struct attribute *hycon_hy46xx_attrs[] = { + &hycon_hy46xx_attr_threshold.dattr.attr, + &hycon_hy46xx_attr_glove_enable.dattr.attr, + &hycon_hy46xx_attr_report_speed.dattr.attr, + &hycon_hy46xx_attr_noise_filter_enable.dattr.attr, + &hycon_hy46xx_attr_filter_data.dattr.attr, + &hycon_hy46xx_attr_gain.dattr.attr, + &hycon_hy46xx_attr_edge_offset.dattr.attr, + &hycon_hy46xx_attr_fw_version.dattr.attr, + &hycon_hy46xx_attr_lib_version.dattr.attr, + &hycon_hy46xx_attr_tp_information.dattr.attr, + &hycon_hy46xx_attr_tp_chip_id.dattr.attr, + &hycon_hy46xx_attr_bootloader_version.dattr.attr, + NULL +}; + +static const struct attribute_group hycon_hy46xx_attr_group = { + .attrs = hycon_hy46xx_attrs, +}; + +static void hycon_hy46xx_get_defaults(struct device *dev, struct hycon_hy46xx_data *tsdata) +{ + bool val_bool; + int error; + u32 val; + + error = device_property_read_u32(dev, "hycon,threshold", &val); + if (!error) { + error = regmap_write(tsdata->regmap, HY46XX_THRESHOLD, val); + if (error < 0) + goto out; + + tsdata->threshold = val; + } + + val_bool = device_property_read_bool(dev, "hycon,glove-enable"); + error = regmap_write(tsdata->regmap, HY46XX_GLOVE_EN, val_bool); + if (error < 0) + goto out; + tsdata->glove_enable = val_bool; + + error = device_property_read_u32(dev, "hycon,report-speed-hz", &val); + if (!error) { + error = regmap_write(tsdata->regmap, HY46XX_REPORT_SPEED, val); + if (error < 0) + goto out; + + tsdata->report_speed = val; + } + + val_bool = device_property_read_bool(dev, "hycon,noise-filter-enable"); + error = regmap_write(tsdata->regmap, HY46XX_PWR_NOISE_EN, val_bool); + if (error < 0) + goto out; + tsdata->noise_filter_enable = val_bool; + + error = device_property_read_u32(dev, "hycon,filter-data", &val); + if (!error) { + error = regmap_write(tsdata->regmap, HY46XX_FILTER_DATA, val); + if (error < 0) + goto out; + + tsdata->filter_data = val; + } + + error = device_property_read_u32(dev, "hycon,gain", &val); + if (!error) { + error = regmap_write(tsdata->regmap, HY46XX_GAIN, val); + if (error < 0) + goto out; + + tsdata->gain = val; + } + + error = device_property_read_u32(dev, "hycon,edge-offset", &val); + if (!error) { + error = regmap_write(tsdata->regmap, HY46XX_EDGE_OFFSET, val); + if (error < 0) + goto out; + + tsdata->edge_offset = val; + } + + return; +out: + dev_err(&tsdata->client->dev, "Failed to set default settings"); +} + +static void hycon_hy46xx_get_parameters(struct hycon_hy46xx_data *tsdata) +{ + int error; + u32 val; + + error = regmap_read(tsdata->regmap, HY46XX_THRESHOLD, &val); + if (error < 0) + goto out; + tsdata->threshold = val; + + error = regmap_read(tsdata->regmap, HY46XX_GLOVE_EN, &val); + if (error < 0) + goto out; + tsdata->glove_enable = val; + + error = regmap_read(tsdata->regmap, HY46XX_REPORT_SPEED, &val); + if (error < 0) + goto out; + tsdata->report_speed = val; + + error = regmap_read(tsdata->regmap, HY46XX_PWR_NOISE_EN, &val); + if (error < 0) + goto out; + tsdata->noise_filter_enable = val; + + error = regmap_read(tsdata->regmap, HY46XX_FILTER_DATA, &val); + if (error < 0) + goto out; + tsdata->filter_data = val; + + error = regmap_read(tsdata->regmap, HY46XX_GAIN, &val); + if (error < 0) + goto out; + tsdata->gain = val; + + error = regmap_read(tsdata->regmap, HY46XX_EDGE_OFFSET, &val); + if (error < 0) + goto out; + tsdata->edge_offset = val; + + error = regmap_read(tsdata->regmap, HY46XX_RX_NR_USED, &val); + if (error < 0) + goto out; + tsdata->rx_number_used = val; + + error = regmap_read(tsdata->regmap, HY46XX_TX_NR_USED, &val); + if (error < 0) + goto out; + tsdata->tx_number_used = val; + + error = regmap_read(tsdata->regmap, HY46XX_PWR_MODE, &val); + if (error < 0) + goto out; + tsdata->power_mode = val; + + error = regmap_read(tsdata->regmap, HY46XX_FW_VERSION, &val); + if (error < 0) + goto out; + tsdata->fw_version = val; + + error = regmap_read(tsdata->regmap, HY46XX_LIB_VERSION, &val); + if (error < 0) + goto out; + tsdata->lib_version = val; + + error = regmap_read(tsdata->regmap, HY46XX_TP_INFO, &val); + if (error < 0) + goto out; + tsdata->tp_information = val; + + error = regmap_read(tsdata->regmap, HY46XX_TP_CHIP_ID, &val); + if (error < 0) + goto out; + tsdata->tp_chip_id = val; + + error = regmap_read(tsdata->regmap, HY46XX_BOOT_VER, &val); + if (error < 0) + goto out; + tsdata->bootloader_version = val; + + return; +out: + dev_err(&tsdata->client->dev, "Failed to read default settings"); +} + +static void hycon_hy46xx_disable_regulator(void *arg) +{ + struct hycon_hy46xx_data *data = arg; + + regulator_disable(data->vcc); +} + +static int hycon_hy46xx_probe(struct i2c_client *client) +{ + struct hycon_hy46xx_data *tsdata; + struct input_dev *input; + int error; + + dev_dbg(&client->dev, "probing for HYCON HY46XX I2C\n"); + + tsdata = devm_kzalloc(&client->dev, sizeof(*tsdata), GFP_KERNEL); + if (!tsdata) + return -ENOMEM; + + tsdata->vcc = devm_regulator_get(&client->dev, "vcc"); + if (IS_ERR(tsdata->vcc)) { + error = PTR_ERR(tsdata->vcc); + if (error != -EPROBE_DEFER) + dev_err(&client->dev, + "failed to request regulator: %d\n", error); + return error; + } + + error = regulator_enable(tsdata->vcc); + if (error < 0) { + dev_err(&client->dev, "failed to enable vcc: %d\n", error); + return error; + } + + error = devm_add_action_or_reset(&client->dev, + hycon_hy46xx_disable_regulator, + tsdata); + if (error) + return error; + + tsdata->reset_gpio = devm_gpiod_get_optional(&client->dev, + "reset", GPIOD_OUT_LOW); + if (IS_ERR(tsdata->reset_gpio)) { + error = PTR_ERR(tsdata->reset_gpio); + dev_err(&client->dev, + "Failed to request GPIO reset pin, error %d\n", error); + return error; + } + + if (tsdata->reset_gpio) { + usleep_range(5000, 6000); + gpiod_set_value_cansleep(tsdata->reset_gpio, 1); + usleep_range(5000, 6000); + gpiod_set_value_cansleep(tsdata->reset_gpio, 0); + msleep(1000); + } + + input = devm_input_allocate_device(&client->dev); + if (!input) { + dev_err(&client->dev, "failed to allocate input device.\n"); + return -ENOMEM; + } + + mutex_init(&tsdata->mutex); + tsdata->client = client; + tsdata->input = input; + + tsdata->regmap = devm_regmap_init_i2c(client, + &hycon_hy46xx_i2c_regmap_config); + if (IS_ERR(tsdata->regmap)) { + dev_err(&client->dev, "regmap allocation failed\n"); + return PTR_ERR(tsdata->regmap); + } + + hycon_hy46xx_get_defaults(&client->dev, tsdata); + hycon_hy46xx_get_parameters(tsdata); + + input->name = "Hycon Capacitive Touch"; + input->id.bustype = BUS_I2C; + input->dev.parent = &client->dev; + + input_set_abs_params(input, ABS_MT_POSITION_X, 0, -1, 0, 0); + input_set_abs_params(input, ABS_MT_POSITION_Y, 0, -1, 0, 0); + + touchscreen_parse_properties(input, true, &tsdata->prop); + + error = input_mt_init_slots(input, HY46XX_MAX_SUPPORTED_POINTS, + INPUT_MT_DIRECT); + if (error) { + dev_err(&client->dev, "Unable to init MT slots.\n"); + return error; + } + + i2c_set_clientdata(client, tsdata); + + error = devm_request_threaded_irq(&client->dev, client->irq, + NULL, hycon_hy46xx_isr, IRQF_ONESHOT, + client->name, tsdata); + if (error) { + dev_err(&client->dev, "Unable to request touchscreen IRQ.\n"); + return error; + } + + error = devm_device_add_group(&client->dev, &hycon_hy46xx_attr_group); + if (error) + return error; + + error = input_register_device(input); + if (error) + return error; + + dev_dbg(&client->dev, + "HYCON HY46XX initialized: IRQ %d, Reset pin %d.\n", + client->irq, + tsdata->reset_gpio ? desc_to_gpio(tsdata->reset_gpio) : -1); + + return 0; +} + +static const struct i2c_device_id hycon_hy46xx_id[] = { + { .name = "hy4613" }, + { .name = "hy4614" }, + { .name = "hy4621" }, + { .name = "hy4623" }, + { .name = "hy4633" }, + { .name = "hy4635" }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(i2c, hycon_hy46xx_id); + +static const struct of_device_id hycon_hy46xx_of_match[] = { + { .compatible = "hycon,hy4613" }, + { .compatible = "hycon,hy4614" }, + { .compatible = "hycon,hy4621" }, + { .compatible = "hycon,hy4623" }, + { .compatible = "hycon,hy4633" }, + { .compatible = "hycon,hy4635" }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, hycon_hy46xx_of_match); + +static struct i2c_driver hycon_hy46xx_driver = { + .driver = { + .name = "hycon_hy46xx", + .of_match_table = hycon_hy46xx_of_match, + .probe_type = PROBE_PREFER_ASYNCHRONOUS, + }, + .id_table = hycon_hy46xx_id, + .probe = hycon_hy46xx_probe, +}; + +module_i2c_driver(hycon_hy46xx_driver); + +MODULE_AUTHOR("Giulio Benetti <giulio.benetti@benettiengineering.com>"); +MODULE_DESCRIPTION("HYCON HY46XX I2C Touchscreen Driver"); +MODULE_LICENSE("GPL v2"); |