--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Wacom W9000-series penabled I2C touchscreen driver
+ *
+ * Copyright (c) 2026 Hendrik Noack <hendrik-noack@gmx.de>
+ *
+ * Partially based on vendor driver:
+ * Copyright (C) 2012, Samsung Electronics Co. Ltd.
+ */
+
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/i2c.h>
+#include <linux/input.h>
+#include <linux/input/touchscreen.h>
+#include <linux/interrupt.h>
+#include <linux/lockdep.h>
+#include <linux/regulator/consumer.h>
+#include <linux/unaligned.h>
+
+/* Some chips have flaky firmware that requires many retries before responding. */
+#define CMD_QUERY_RETRIES 8
+
+/* Message length */
+#define CMD_QUERY_NUM_MAX 9
+#define MSG_COORD_NUM_MAX 12
+
+/* Commands */
+#define CMD_QUERY 0x2a
+
+struct wacom_w9000_variant {
+ const u8 cmd_query_num;
+ const u8 msg_coord_num;
+ const char *name;
+};
+
+struct wacom_w9000_data {
+ struct i2c_client *client;
+ struct input_dev *input_dev;
+ const struct wacom_w9000_variant *variant;
+ u16 fw_version;
+
+ struct touchscreen_properties prop;
+ u16 max_pressure;
+
+ struct regulator *regulator;
+
+ struct gpio_desc *flash_mode_gpio;
+ struct gpio_desc *reset_gpio;
+
+ unsigned int irq;
+
+ bool pen_proximity;
+};
+
+static int wacom_w9000_read(struct i2c_client *client, u8 command, u8 len, u8 *data)
+{
+ int error, res;
+ struct i2c_msg msg[] = {
+ {
+ .addr = client->addr,
+ .flags = 0,
+ .buf = &command,
+ .len = sizeof(command),
+ }, {
+ .addr = client->addr,
+ .flags = I2C_M_RD,
+ .buf = data,
+ .len = len,
+ }
+ };
+
+ res = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
+ if (res != ARRAY_SIZE(msg)) {
+ error = res < 0 ? res : -EIO;
+ dev_err(&client->dev, "%s: i2c transfer failed: %d (%d)\n",
+ __func__, error, res);
+ return error;
+ }
+
+ return 0;
+}
+
+static int wacom_w9000_query(struct wacom_w9000_data *wacom_data)
+{
+ struct i2c_client *client = wacom_data->client;
+ struct device *dev = &wacom_data->client->dev;
+ u8 data[CMD_QUERY_NUM_MAX];
+ int retry;
+ int error;
+
+ for (retry = 0; retry < CMD_QUERY_RETRIES; retry++) {
+ error = wacom_w9000_read(client, CMD_QUERY,
+ wacom_data->variant->cmd_query_num,
+ data);
+ if (!error && data[0] == 0x0f)
+ break;
+ }
+
+ if (error)
+ return error;
+
+ if (data[0] != 0x0f)
+ return -EIO;
+
+ dev_dbg(dev, "query: %*ph, %d\n",
+ wacom_data->variant->cmd_query_num, data, retry);
+
+ wacom_data->prop.max_x = get_unaligned_be16(&data[1]);
+ wacom_data->prop.max_y = get_unaligned_be16(&data[3]);
+ wacom_data->max_pressure = get_unaligned_be16(&data[5]);
+ wacom_data->fw_version = get_unaligned_be16(&data[7]);
+
+ dev_dbg(dev, "max_x:%d, max_y:%d, max_pressure:%d, fw:%#x\n",
+ wacom_data->prop.max_x, wacom_data->prop.max_y,
+ wacom_data->max_pressure, wacom_data->fw_version);
+
+ return 0;
+}
+
+static int wacom_w9000_power_on(struct wacom_w9000_data *wacom_data)
+{
+ int error;
+
+ lockdep_assert_held(&wacom_data->input_dev->mutex);
+
+ error = regulator_enable(wacom_data->regulator);
+ if (error) {
+ dev_err(&wacom_data->client->dev, "Failed to enable regulators: %d\n", error);
+ return error;
+ }
+
+ msleep(200);
+
+ gpiod_set_value_cansleep(wacom_data->reset_gpio, 0);
+ enable_irq(wacom_data->irq);
+
+ return 0;
+}
+
+static int wacom_w9000_power_off(struct wacom_w9000_data *wacom_data)
+{
+ lockdep_assert_held(&wacom_data->input_dev->mutex);
+
+ disable_irq(wacom_data->irq);
+ gpiod_set_value_cansleep(wacom_data->reset_gpio, 1);
+ regulator_disable(wacom_data->regulator);
+
+ return 0;
+}
+
+static void wacom_w9000_coord(struct wacom_w9000_data *wacom_data)
+{
+ struct i2c_client *client = wacom_data->client;
+ struct device *dev = &wacom_data->client->dev;
+ u8 data[MSG_COORD_NUM_MAX];
+ bool touch, rubber, side_button;
+ u16 x, y, pressure;
+ u8 distance = 0;
+ int error;
+
+ error = i2c_master_recv(client, data, wacom_data->variant->msg_coord_num);
+ if (error != wacom_data->variant->msg_coord_num) {
+ if (error >= 0)
+ error = -EIO;
+ dev_err_ratelimited(dev, "%s: i2c receive failed (%d)\n", __func__, error);
+ return;
+ }
+
+ dev_dbg(dev, "data: %*ph\n", wacom_data->variant->msg_coord_num, data);
+
+ if (data[0] & BIT(7)) {
+ wacom_data->pen_proximity = true;
+
+ touch = !!(data[0] & BIT(4));
+ side_button = !!(data[0] & BIT(5));
+ rubber = !!(data[0] & BIT(6));
+
+ x = get_unaligned_be16(&data[1]);
+ y = get_unaligned_be16(&data[3]);
+ pressure = get_unaligned_be16(&data[5]);
+
+ if (wacom_data->variant->msg_coord_num > 7)
+ distance = data[7];
+
+ if (x > wacom_data->prop.max_x || y > wacom_data->prop.max_y) {
+ dev_warn_ratelimited(dev, "Coordinates out of range x=%d, y=%d\n", x, y);
+ return;
+ }
+
+ if (pressure > wacom_data->max_pressure) {
+ dev_warn_ratelimited(dev, "Pressure out of range %d\n", pressure);
+ return;
+ }
+
+ touchscreen_report_pos(wacom_data->input_dev, &wacom_data->prop, x, y, false);
+ input_report_abs(wacom_data->input_dev, ABS_PRESSURE, pressure);
+
+ if (wacom_data->variant->msg_coord_num > 7)
+ input_report_abs(wacom_data->input_dev, ABS_DISTANCE, distance);
+
+ input_report_key(wacom_data->input_dev, BTN_STYLUS, side_button);
+ input_report_key(wacom_data->input_dev, BTN_TOUCH, touch);
+ input_report_key(wacom_data->input_dev, BTN_TOOL_PEN, !rubber);
+ input_report_key(wacom_data->input_dev, BTN_TOOL_RUBBER, rubber);
+ input_sync(wacom_data->input_dev);
+ } else if (wacom_data->pen_proximity) {
+ input_report_abs(wacom_data->input_dev, ABS_PRESSURE, 0);
+
+ if (wacom_data->variant->msg_coord_num > 7)
+ input_report_abs(wacom_data->input_dev, ABS_DISTANCE, 255);
+
+ input_report_key(wacom_data->input_dev, BTN_STYLUS, 0);
+ input_report_key(wacom_data->input_dev, BTN_TOUCH, 0);
+ input_report_key(wacom_data->input_dev, BTN_TOOL_PEN, 0);
+ input_report_key(wacom_data->input_dev, BTN_TOOL_RUBBER, 0);
+ input_sync(wacom_data->input_dev);
+
+ wacom_data->pen_proximity = false;
+ }
+}
+
+static irqreturn_t wacom_w9000_interrupt(int irq, void *dev_id)
+{
+ struct wacom_w9000_data *wacom_data = dev_id;
+
+ wacom_w9000_coord(wacom_data);
+
+ return IRQ_HANDLED;
+}
+
+static int wacom_w9000_open(struct input_dev *dev)
+{
+ struct wacom_w9000_data *wacom_data = input_get_drvdata(dev);
+
+ return wacom_w9000_power_on(wacom_data);
+}
+
+static void wacom_w9000_close(struct input_dev *dev)
+{
+ struct wacom_w9000_data *wacom_data = input_get_drvdata(dev);
+
+ wacom_w9000_power_off(wacom_data);
+}
+
+static int wacom_w9000_probe(struct i2c_client *client)
+{
+ struct device *dev = &client->dev;
+ struct wacom_w9000_data *wacom_data;
+ struct input_dev *input_dev;
+ int error;
+ u32 val;
+
+ if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
+ dev_err(dev, "i2c_check_functionality error\n");
+ return -EIO;
+ }
+
+ wacom_data = devm_kzalloc(dev, sizeof(*wacom_data), GFP_KERNEL);
+ if (!wacom_data)
+ return -ENOMEM;
+
+ wacom_data->variant = i2c_get_match_data(client);
+ if (!wacom_data->variant) {
+ dev_err(dev, "No i2c match_data available\n");
+ return -EINVAL;
+ }
+
+ if (wacom_data->variant->cmd_query_num > CMD_QUERY_NUM_MAX ||
+ wacom_data->variant->msg_coord_num > MSG_COORD_NUM_MAX) {
+ dev_err(dev, "Length of message for %s exceeds the maximum\n",
+ wacom_data->variant->name);
+ return -EINVAL;
+ }
+
+ if (wacom_data->variant->msg_coord_num < 7) {
+ dev_err(dev, "Length of coordinates message for %s too short\n",
+ wacom_data->variant->name);
+ return -EINVAL;
+ }
+
+ wacom_data->client = client;
+ wacom_data->irq = client->irq;
+ i2c_set_clientdata(client, wacom_data);
+
+ wacom_data->regulator = devm_regulator_get(dev, "vdd");
+ if (IS_ERR(wacom_data->regulator))
+ return dev_err_probe(dev, PTR_ERR(wacom_data->regulator),
+ "Failed to get regulators\n");
+
+ wacom_data->flash_mode_gpio = devm_gpiod_get_optional(dev, "flash-mode", GPIOD_OUT_LOW);
+ if (IS_ERR(wacom_data->flash_mode_gpio))
+ return dev_err_probe(dev, PTR_ERR(wacom_data->flash_mode_gpio),
+ "Failed to get flash-mode gpio\n");
+
+ wacom_data->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
+ if (IS_ERR(wacom_data->reset_gpio))
+ return dev_err_probe(dev, PTR_ERR(wacom_data->reset_gpio),
+ "Failed to get reset gpio\n");
+
+ error = regulator_enable(wacom_data->regulator);
+ if (error)
+ return dev_err_probe(dev, error, "Failed to enable regulators\n");
+
+ msleep(200);
+
+ gpiod_set_value_cansleep(wacom_data->reset_gpio, 0);
+
+ error = wacom_w9000_query(wacom_data);
+
+ gpiod_set_value_cansleep(wacom_data->reset_gpio, 1);
+ regulator_disable(wacom_data->regulator);
+
+ if (error)
+ return dev_err_probe(dev, error, "Failed to query\n");
+
+ error = devm_request_threaded_irq(dev, wacom_data->irq, NULL, wacom_w9000_interrupt,
+ IRQF_ONESHOT | IRQF_NO_AUTOEN, client->name, wacom_data);
+ if (error)
+ return dev_err_probe(dev, error, "Failed to register interrupt\n");
+
+ input_dev = devm_input_allocate_device(dev);
+ if (!input_dev)
+ return -ENOMEM;
+
+ wacom_data->input_dev = input_dev;
+ input_set_drvdata(input_dev, wacom_data);
+
+ input_dev->name = wacom_data->variant->name;
+ input_dev->id.bustype = BUS_I2C;
+ input_dev->id.vendor = 0x56a;
+ input_dev->id.version = wacom_data->fw_version;
+ input_dev->open = wacom_w9000_open;
+ input_dev->close = wacom_w9000_close;
+
+ input_set_capability(input_dev, EV_KEY, BTN_TOUCH);
+ input_set_capability(input_dev, EV_KEY, BTN_TOOL_PEN);
+ input_set_capability(input_dev, EV_KEY, BTN_TOOL_RUBBER);
+ input_set_capability(input_dev, EV_KEY, BTN_STYLUS);
+
+ input_set_abs_params(input_dev, ABS_X, 0, wacom_data->prop.max_x, 4, 0);
+ input_set_abs_params(input_dev, ABS_Y, 0, wacom_data->prop.max_y, 4, 0);
+ input_set_abs_params(input_dev, ABS_PRESSURE, 0, wacom_data->max_pressure, 0, 0);
+
+ if (wacom_data->variant->msg_coord_num > 7)
+ input_set_abs_params(input_dev, ABS_DISTANCE, 0, 255, 0, 0);
+
+ touchscreen_parse_properties(input_dev, false, &wacom_data->prop);
+
+ dev_info(dev, "%s size X%uY%u\n", wacom_data->variant->name,
+ wacom_data->prop.max_x, wacom_data->prop.max_y);
+
+ error = device_property_read_u32(dev, "touchscreen-x-mm", &val);
+ if (!error && val)
+ input_abs_set_res(input_dev, wacom_data->prop.swap_x_y ? ABS_Y : ABS_X,
+ wacom_data->prop.max_x / val);
+ error = device_property_read_u32(dev, "touchscreen-y-mm", &val);
+ if (!error && val)
+ input_abs_set_res(input_dev, wacom_data->prop.swap_x_y ? ABS_X : ABS_Y,
+ wacom_data->prop.max_y / val);
+
+ error = input_register_device(wacom_data->input_dev);
+ if (error)
+ return dev_err_probe(dev, error, "Failed to register input device\n");
+
+ return 0;
+}
+
+static int wacom_w9000_suspend(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct wacom_w9000_data *wacom_data = i2c_get_clientdata(client);
+
+ guard(mutex)(&wacom_data->input_dev->mutex);
+
+ if (input_device_enabled(wacom_data->input_dev))
+ return wacom_w9000_power_off(wacom_data);
+
+ return 0;
+}
+
+static int wacom_w9000_resume(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct wacom_w9000_data *wacom_data = i2c_get_clientdata(client);
+
+ guard(mutex)(&wacom_data->input_dev->mutex);
+
+ if (input_device_enabled(wacom_data->input_dev))
+ return wacom_w9000_power_on(wacom_data);
+
+ return 0;
+}
+
+static DEFINE_SIMPLE_DEV_PM_OPS(wacom_w9000_pm, wacom_w9000_suspend, wacom_w9000_resume);
+
+static const struct wacom_w9000_variant w9002 = {
+ .cmd_query_num = 9,
+ .msg_coord_num = 7,
+ .name = "Wacom W9002 Digitizer",
+};
+
+static const struct wacom_w9000_variant w9007a_lt03 = {
+ .cmd_query_num = 9,
+ .msg_coord_num = 8,
+ .name = "Wacom W9007A LT03 Digitizer",
+};
+
+static const struct wacom_w9000_variant w9007a_v1 = {
+ .cmd_query_num = 9,
+ .msg_coord_num = 12,
+ .name = "Wacom W9007A V1 Digitizer",
+};
+
+static const struct of_device_id wacom_w9000_of_match[] = {
+ { .compatible = "wacom,w9002", .data = &w9002 },
+ { .compatible = "wacom,w9007a-lt03", .data = &w9007a_lt03, },
+ { .compatible = "wacom,w9007a-v1", .data = &w9007a_v1, },
+ { }
+};
+MODULE_DEVICE_TABLE(of, wacom_w9000_of_match);
+
+static const struct i2c_device_id wacom_w9000_id[] = {
+ { .name = "w9002", .driver_data = (kernel_ulong_t)&w9002 },
+ { .name = "w9007a-lt03", .driver_data = (kernel_ulong_t)&w9007a_lt03 },
+ { .name = "w9007a-v1", .driver_data = (kernel_ulong_t)&w9007a_v1 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, wacom_w9000_id);
+
+static struct i2c_driver wacom_w9000_driver = {
+ .driver = {
+ .name = "wacom_w9000",
+ .of_match_table = wacom_w9000_of_match,
+ .pm = pm_sleep_ptr(&wacom_w9000_pm),
+ },
+ .probe = wacom_w9000_probe,
+ .id_table = wacom_w9000_id,
+};
+module_i2c_driver(wacom_w9000_driver);
+
+MODULE_AUTHOR("Hendrik Noack <hendrik-noack@gmx.de>");
+MODULE_DESCRIPTION("Wacom W9000-series penabled touchscreen driver");
+MODULE_LICENSE("GPL");
projects / thirdparty / kernel / linux.git / commitdiff
