diff options
Diffstat (limited to 'drivers/input/touchscreen/novatek-nvt-ts.c')
| -rw-r--r-- | drivers/input/touchscreen/novatek-nvt-ts.c | 299 |
1 files changed, 299 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/novatek-nvt-ts.c b/drivers/input/touchscreen/novatek-nvt-ts.c new file mode 100644 index 0000000000..1a797e410a --- /dev/null +++ b/drivers/input/touchscreen/novatek-nvt-ts.c @@ -0,0 +1,299 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Driver for Novatek NT11205 i2c touchscreen controller as found + * on the Acer Iconia One 7 B1-750 tablet. + * + * Copyright (c) 2023 Hans de Goede <hdegoede@redhat.com> + */ + +#include <linux/delay.h> +#include <linux/gpio/consumer.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> + +#include <asm/unaligned.h> + +#define NVT_TS_TOUCH_START 0x00 +#define NVT_TS_TOUCH_SIZE 6 + +#define NVT_TS_PARAMETERS_START 0x78 +/* These are offsets from NVT_TS_PARAMETERS_START */ +#define NVT_TS_PARAMS_WIDTH 0x04 +#define NVT_TS_PARAMS_HEIGHT 0x06 +#define NVT_TS_PARAMS_MAX_TOUCH 0x09 +#define NVT_TS_PARAMS_MAX_BUTTONS 0x0a +#define NVT_TS_PARAMS_IRQ_TYPE 0x0b +#define NVT_TS_PARAMS_WAKE_TYPE 0x0c +#define NVT_TS_PARAMS_CHIP_ID 0x0e +#define NVT_TS_PARAMS_SIZE 0x0f + +#define NVT_TS_SUPPORTED_WAKE_TYPE 0x05 +#define NVT_TS_SUPPORTED_CHIP_ID 0x05 + +#define NVT_TS_MAX_TOUCHES 10 +#define NVT_TS_MAX_SIZE 4096 + +#define NVT_TS_TOUCH_INVALID 0xff +#define NVT_TS_TOUCH_SLOT_SHIFT 3 +#define NVT_TS_TOUCH_TYPE_MASK GENMASK(2, 0) +#define NVT_TS_TOUCH_NEW 1 +#define NVT_TS_TOUCH_UPDATE 2 +#define NVT_TS_TOUCH_RELEASE 3 + +static const int nvt_ts_irq_type[4] = { + IRQF_TRIGGER_RISING, + IRQF_TRIGGER_FALLING, + IRQF_TRIGGER_LOW, + IRQF_TRIGGER_HIGH +}; + +struct nvt_ts_data { + struct i2c_client *client; + struct input_dev *input; + struct gpio_desc *reset_gpio; + struct touchscreen_properties prop; + int max_touches; + u8 buf[NVT_TS_TOUCH_SIZE * NVT_TS_MAX_TOUCHES]; +}; + +static int nvt_ts_read_data(struct i2c_client *client, u8 reg, u8 *data, int count) +{ + struct i2c_msg msg[2] = { + { + .addr = client->addr, + .len = 1, + .buf = ®, + }, + { + .addr = client->addr, + .flags = I2C_M_RD, + .len = count, + .buf = data, + } + }; + int ret; + + ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg)); + if (ret != ARRAY_SIZE(msg)) { + dev_err(&client->dev, "Error reading from 0x%02x: %d\n", reg, ret); + return (ret < 0) ? ret : -EIO; + } + + return 0; +} + +static irqreturn_t nvt_ts_irq(int irq, void *dev_id) +{ + struct nvt_ts_data *data = dev_id; + struct device *dev = &data->client->dev; + int i, error, slot, x, y; + bool active; + u8 *touch; + + error = nvt_ts_read_data(data->client, NVT_TS_TOUCH_START, data->buf, + data->max_touches * NVT_TS_TOUCH_SIZE); + if (error) + return IRQ_HANDLED; + + for (i = 0; i < data->max_touches; i++) { + touch = &data->buf[i * NVT_TS_TOUCH_SIZE]; + + if (touch[0] == NVT_TS_TOUCH_INVALID) + continue; + + slot = touch[0] >> NVT_TS_TOUCH_SLOT_SHIFT; + if (slot < 1 || slot > data->max_touches) { + dev_warn(dev, "slot %d out of range, ignoring\n", slot); + continue; + } + + switch (touch[0] & NVT_TS_TOUCH_TYPE_MASK) { + case NVT_TS_TOUCH_NEW: + case NVT_TS_TOUCH_UPDATE: + active = true; + break; + case NVT_TS_TOUCH_RELEASE: + active = false; + break; + default: + dev_warn(dev, "slot %d unknown state %d\n", slot, touch[0] & 7); + continue; + } + + slot--; + x = (touch[1] << 4) | (touch[3] >> 4); + y = (touch[2] << 4) | (touch[3] & 0x0f); + + input_mt_slot(data->input, slot); + input_mt_report_slot_state(data->input, MT_TOOL_FINGER, active); + touchscreen_report_pos(data->input, &data->prop, x, y, true); + } + + input_mt_sync_frame(data->input); + input_sync(data->input); + + return IRQ_HANDLED; +} + +static int nvt_ts_start(struct input_dev *dev) +{ + struct nvt_ts_data *data = input_get_drvdata(dev); + + enable_irq(data->client->irq); + gpiod_set_value_cansleep(data->reset_gpio, 0); + + return 0; +} + +static void nvt_ts_stop(struct input_dev *dev) +{ + struct nvt_ts_data *data = input_get_drvdata(dev); + + disable_irq(data->client->irq); + gpiod_set_value_cansleep(data->reset_gpio, 1); +} + +static int nvt_ts_suspend(struct device *dev) +{ + struct nvt_ts_data *data = i2c_get_clientdata(to_i2c_client(dev)); + + mutex_lock(&data->input->mutex); + if (input_device_enabled(data->input)) + nvt_ts_stop(data->input); + mutex_unlock(&data->input->mutex); + + return 0; +} + +static int nvt_ts_resume(struct device *dev) +{ + struct nvt_ts_data *data = i2c_get_clientdata(to_i2c_client(dev)); + + mutex_lock(&data->input->mutex); + if (input_device_enabled(data->input)) + nvt_ts_start(data->input); + mutex_unlock(&data->input->mutex); + + return 0; +} + +static DEFINE_SIMPLE_DEV_PM_OPS(nvt_ts_pm_ops, nvt_ts_suspend, nvt_ts_resume); + +static int nvt_ts_probe(struct i2c_client *client) +{ + struct device *dev = &client->dev; + int error, width, height, irq_type; + struct nvt_ts_data *data; + struct input_dev *input; + + if (!client->irq) { + dev_err(dev, "Error no irq specified\n"); + return -EINVAL; + } + + data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->client = client; + i2c_set_clientdata(client, data); + + data->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW); + error = PTR_ERR_OR_ZERO(data->reset_gpio); + if (error) { + dev_err(dev, "failed to request reset GPIO: %d\n", error); + return error; + } + + /* Wait for controller to come out of reset before params read */ + msleep(100); + error = nvt_ts_read_data(data->client, NVT_TS_PARAMETERS_START, + data->buf, NVT_TS_PARAMS_SIZE); + gpiod_set_value_cansleep(data->reset_gpio, 1); /* Put back in reset */ + if (error) + return error; + + width = get_unaligned_be16(&data->buf[NVT_TS_PARAMS_WIDTH]); + height = get_unaligned_be16(&data->buf[NVT_TS_PARAMS_HEIGHT]); + data->max_touches = data->buf[NVT_TS_PARAMS_MAX_TOUCH]; + irq_type = data->buf[NVT_TS_PARAMS_IRQ_TYPE]; + + if (width > NVT_TS_MAX_SIZE || height >= NVT_TS_MAX_SIZE || + data->max_touches > NVT_TS_MAX_TOUCHES || + irq_type >= ARRAY_SIZE(nvt_ts_irq_type) || + data->buf[NVT_TS_PARAMS_WAKE_TYPE] != NVT_TS_SUPPORTED_WAKE_TYPE || + data->buf[NVT_TS_PARAMS_CHIP_ID] != NVT_TS_SUPPORTED_CHIP_ID) { + dev_err(dev, "Unsupported touchscreen parameters: %*ph\n", + NVT_TS_PARAMS_SIZE, data->buf); + return -EIO; + } + + dev_dbg(dev, "Detected %dx%d touchscreen with %d max touches\n", + width, height, data->max_touches); + + if (data->buf[NVT_TS_PARAMS_MAX_BUTTONS]) + dev_warn(dev, "Touchscreen buttons are not supported\n"); + + input = devm_input_allocate_device(dev); + if (!input) + return -ENOMEM; + + input->name = client->name; + input->id.bustype = BUS_I2C; + input->open = nvt_ts_start; + input->close = nvt_ts_stop; + + input_set_abs_params(input, ABS_MT_POSITION_X, 0, width - 1, 0, 0); + input_set_abs_params(input, ABS_MT_POSITION_Y, 0, height - 1, 0, 0); + touchscreen_parse_properties(input, true, &data->prop); + + error = input_mt_init_slots(input, data->max_touches, + INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED); + if (error) + return error; + + data->input = input; + input_set_drvdata(input, data); + + error = devm_request_threaded_irq(dev, client->irq, NULL, nvt_ts_irq, + IRQF_ONESHOT | IRQF_NO_AUTOEN | + nvt_ts_irq_type[irq_type], + client->name, data); + if (error) { + dev_err(dev, "failed to request irq: %d\n", error); + return error; + } + + error = input_register_device(input); + if (error) { + dev_err(dev, "failed to register input device: %d\n", error); + return error; + } + + return 0; +} + +static const struct i2c_device_id nvt_ts_i2c_id[] = { + { "NVT-ts" }, + { } +}; +MODULE_DEVICE_TABLE(i2c, nvt_ts_i2c_id); + +static struct i2c_driver nvt_ts_driver = { + .driver = { + .name = "novatek-nvt-ts", + .pm = pm_sleep_ptr(&nvt_ts_pm_ops), + }, + .probe = nvt_ts_probe, + .id_table = nvt_ts_i2c_id, +}; + +module_i2c_driver(nvt_ts_driver); + +MODULE_DESCRIPTION("Novatek NT11205 touchscreen driver"); +MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>"); +MODULE_LICENSE("GPL"); |