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-rw-r--r--drivers/input/touchscreen/exc3000.c470
1 files changed, 470 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/exc3000.c b/drivers/input/touchscreen/exc3000.c
new file mode 100644
index 000000000..615646a03
--- /dev/null
+++ b/drivers/input/touchscreen/exc3000.c
@@ -0,0 +1,470 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Driver for I2C connected EETI EXC3000 multiple touch controller
+ *
+ * Copyright (C) 2017 Ahmet Inan <inan@distec.de>
+ *
+ * minimal implementation based on egalax_ts.c and egalax_i2c.c
+ */
+
+#include <linux/bitops.h>
+#include <linux/delay.h>
+#include <linux/device.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/module.h>
+#include <linux/of.h>
+#include <linux/sizes.h>
+#include <linux/timer.h>
+#include <asm/unaligned.h>
+
+#define EXC3000_NUM_SLOTS 10
+#define EXC3000_SLOTS_PER_FRAME 5
+#define EXC3000_LEN_FRAME 66
+#define EXC3000_LEN_VENDOR_REQUEST 68
+#define EXC3000_LEN_POINT 10
+
+#define EXC3000_LEN_MODEL_NAME 16
+#define EXC3000_LEN_FW_VERSION 16
+
+#define EXC3000_VENDOR_EVENT 0x03
+#define EXC3000_MT1_EVENT 0x06
+#define EXC3000_MT2_EVENT 0x18
+
+#define EXC3000_TIMEOUT_MS 100
+
+#define EXC3000_RESET_MS 10
+#define EXC3000_READY_MS 100
+
+static const struct i2c_device_id exc3000_id[];
+
+struct eeti_dev_info {
+ const char *name;
+ int max_xy;
+};
+
+enum eeti_dev_id {
+ EETI_EXC3000,
+ EETI_EXC80H60,
+ EETI_EXC80H84,
+};
+
+static struct eeti_dev_info exc3000_info[] = {
+ [EETI_EXC3000] = {
+ .name = "EETI EXC3000 Touch Screen",
+ .max_xy = SZ_4K - 1,
+ },
+ [EETI_EXC80H60] = {
+ .name = "EETI EXC80H60 Touch Screen",
+ .max_xy = SZ_16K - 1,
+ },
+ [EETI_EXC80H84] = {
+ .name = "EETI EXC80H84 Touch Screen",
+ .max_xy = SZ_16K - 1,
+ },
+};
+
+struct exc3000_data {
+ struct i2c_client *client;
+ const struct eeti_dev_info *info;
+ struct input_dev *input;
+ struct touchscreen_properties prop;
+ struct gpio_desc *reset;
+ struct timer_list timer;
+ u8 buf[2 * EXC3000_LEN_FRAME];
+ struct completion wait_event;
+ struct mutex query_lock;
+};
+
+static void exc3000_report_slots(struct input_dev *input,
+ struct touchscreen_properties *prop,
+ const u8 *buf, int num)
+{
+ for (; num--; buf += EXC3000_LEN_POINT) {
+ if (buf[0] & BIT(0)) {
+ input_mt_slot(input, buf[1]);
+ input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
+ touchscreen_report_pos(input, prop,
+ get_unaligned_le16(buf + 2),
+ get_unaligned_le16(buf + 4),
+ true);
+ }
+ }
+}
+
+static void exc3000_timer(struct timer_list *t)
+{
+ struct exc3000_data *data = from_timer(data, t, timer);
+
+ input_mt_sync_frame(data->input);
+ input_sync(data->input);
+}
+
+static inline void exc3000_schedule_timer(struct exc3000_data *data)
+{
+ mod_timer(&data->timer, jiffies + msecs_to_jiffies(EXC3000_TIMEOUT_MS));
+}
+
+static void exc3000_shutdown_timer(void *timer)
+{
+ del_timer_sync(timer);
+}
+
+static int exc3000_read_frame(struct exc3000_data *data, u8 *buf)
+{
+ struct i2c_client *client = data->client;
+ int ret;
+
+ ret = i2c_master_send(client, "'", 2);
+ if (ret < 0)
+ return ret;
+
+ if (ret != 2)
+ return -EIO;
+
+ ret = i2c_master_recv(client, buf, EXC3000_LEN_FRAME);
+ if (ret < 0)
+ return ret;
+
+ if (ret != EXC3000_LEN_FRAME)
+ return -EIO;
+
+ if (get_unaligned_le16(buf) != EXC3000_LEN_FRAME)
+ return -EINVAL;
+
+ return 0;
+}
+
+static int exc3000_handle_mt_event(struct exc3000_data *data)
+{
+ struct input_dev *input = data->input;
+ int ret, total_slots;
+ u8 *buf = data->buf;
+
+ total_slots = buf[3];
+ if (!total_slots || total_slots > EXC3000_NUM_SLOTS) {
+ ret = -EINVAL;
+ goto out_fail;
+ }
+
+ if (total_slots > EXC3000_SLOTS_PER_FRAME) {
+ /* Read 2nd frame to get the rest of the contacts. */
+ ret = exc3000_read_frame(data, buf + EXC3000_LEN_FRAME);
+ if (ret)
+ goto out_fail;
+
+ /* 2nd chunk must have number of contacts set to 0. */
+ if (buf[EXC3000_LEN_FRAME + 3] != 0) {
+ ret = -EINVAL;
+ goto out_fail;
+ }
+ }
+
+ /*
+ * We read full state successfully, no contacts will be "stuck".
+ */
+ del_timer_sync(&data->timer);
+
+ while (total_slots > 0) {
+ int slots = min(total_slots, EXC3000_SLOTS_PER_FRAME);
+
+ exc3000_report_slots(input, &data->prop, buf + 4, slots);
+ total_slots -= slots;
+ buf += EXC3000_LEN_FRAME;
+ }
+
+ input_mt_sync_frame(input);
+ input_sync(input);
+
+ return 0;
+
+out_fail:
+ /* Schedule a timer to release "stuck" contacts */
+ exc3000_schedule_timer(data);
+
+ return ret;
+}
+
+static irqreturn_t exc3000_interrupt(int irq, void *dev_id)
+{
+ struct exc3000_data *data = dev_id;
+ u8 *buf = data->buf;
+ int ret;
+
+ ret = exc3000_read_frame(data, buf);
+ if (ret) {
+ /* Schedule a timer to release "stuck" contacts */
+ exc3000_schedule_timer(data);
+ goto out;
+ }
+
+ switch (buf[2]) {
+ case EXC3000_VENDOR_EVENT:
+ complete(&data->wait_event);
+ break;
+
+ case EXC3000_MT1_EVENT:
+ case EXC3000_MT2_EVENT:
+ exc3000_handle_mt_event(data);
+ break;
+
+ default:
+ break;
+ }
+
+out:
+ return IRQ_HANDLED;
+}
+
+static int exc3000_vendor_data_request(struct exc3000_data *data, u8 *request,
+ u8 request_len, u8 *response, int timeout)
+{
+ u8 buf[EXC3000_LEN_VENDOR_REQUEST] = { 0x67, 0x00, 0x42, 0x00, 0x03 };
+ int ret;
+ unsigned long time_left;
+
+ mutex_lock(&data->query_lock);
+
+ reinit_completion(&data->wait_event);
+
+ buf[5] = request_len;
+ memcpy(&buf[6], request, request_len);
+
+ ret = i2c_master_send(data->client, buf, EXC3000_LEN_VENDOR_REQUEST);
+ if (ret < 0)
+ goto out_unlock;
+
+ if (response) {
+ time_left = wait_for_completion_timeout(&data->wait_event,
+ timeout * HZ);
+ if (time_left == 0) {
+ ret = -ETIMEDOUT;
+ goto out_unlock;
+ }
+
+ if (data->buf[3] >= EXC3000_LEN_FRAME) {
+ ret = -ENOSPC;
+ goto out_unlock;
+ }
+
+ memcpy(response, &data->buf[4], data->buf[3]);
+ ret = data->buf[3];
+ }
+
+out_unlock:
+ mutex_unlock(&data->query_lock);
+
+ return ret;
+}
+
+static ssize_t fw_version_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct exc3000_data *data = i2c_get_clientdata(client);
+ u8 response[EXC3000_LEN_FRAME];
+ int ret;
+
+ /* query bootloader info */
+ ret = exc3000_vendor_data_request(data,
+ (u8[]){0x39, 0x02}, 2, response, 1);
+ if (ret < 0)
+ return ret;
+
+ /*
+ * If the bootloader version is non-zero then the device is in
+ * bootloader mode and won't answer a query for the application FW
+ * version, so we just use the bootloader version info.
+ */
+ if (response[2] || response[3])
+ return sprintf(buf, "%d.%d\n", response[2], response[3]);
+
+ ret = exc3000_vendor_data_request(data, (u8[]){'D'}, 1, response, 1);
+ if (ret < 0)
+ return ret;
+
+ return sprintf(buf, "%s\n", &response[1]);
+}
+static DEVICE_ATTR_RO(fw_version);
+
+static ssize_t model_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct exc3000_data *data = i2c_get_clientdata(client);
+ u8 response[EXC3000_LEN_FRAME];
+ int ret;
+
+ ret = exc3000_vendor_data_request(data, (u8[]){'E'}, 1, response, 1);
+ if (ret < 0)
+ return ret;
+
+ return sprintf(buf, "%s\n", &response[1]);
+}
+static DEVICE_ATTR_RO(model);
+
+static ssize_t type_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct exc3000_data *data = i2c_get_clientdata(client);
+ u8 response[EXC3000_LEN_FRAME];
+ int ret;
+
+ ret = exc3000_vendor_data_request(data, (u8[]){'F'}, 1, response, 1);
+ if (ret < 0)
+ return ret;
+
+ return sprintf(buf, "%s\n", &response[1]);
+}
+static DEVICE_ATTR_RO(type);
+
+static struct attribute *sysfs_attrs[] = {
+ &dev_attr_fw_version.attr,
+ &dev_attr_model.attr,
+ &dev_attr_type.attr,
+ NULL
+};
+
+static struct attribute_group exc3000_attribute_group = {
+ .attrs = sysfs_attrs
+};
+
+static int exc3000_probe(struct i2c_client *client)
+{
+ struct exc3000_data *data;
+ struct input_dev *input;
+ int error, max_xy, retry;
+
+ data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->client = client;
+ data->info = device_get_match_data(&client->dev);
+ if (!data->info) {
+ enum eeti_dev_id eeti_dev_id =
+ i2c_match_id(exc3000_id, client)->driver_data;
+ data->info = &exc3000_info[eeti_dev_id];
+ }
+ timer_setup(&data->timer, exc3000_timer, 0);
+ init_completion(&data->wait_event);
+ mutex_init(&data->query_lock);
+
+ data->reset = devm_gpiod_get_optional(&client->dev, "reset",
+ GPIOD_OUT_HIGH);
+ if (IS_ERR(data->reset))
+ return PTR_ERR(data->reset);
+
+ if (data->reset) {
+ msleep(EXC3000_RESET_MS);
+ gpiod_set_value_cansleep(data->reset, 0);
+ msleep(EXC3000_READY_MS);
+ }
+
+ input = devm_input_allocate_device(&client->dev);
+ if (!input)
+ return -ENOMEM;
+
+ data->input = input;
+ input_set_drvdata(input, data);
+
+ input->name = data->info->name;
+ input->id.bustype = BUS_I2C;
+
+ max_xy = data->info->max_xy;
+ input_set_abs_params(input, ABS_MT_POSITION_X, 0, max_xy, 0, 0);
+ input_set_abs_params(input, ABS_MT_POSITION_Y, 0, max_xy, 0, 0);
+
+ touchscreen_parse_properties(input, true, &data->prop);
+
+ error = input_mt_init_slots(input, EXC3000_NUM_SLOTS,
+ INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
+ if (error)
+ return error;
+
+ error = input_register_device(input);
+ if (error)
+ return error;
+
+ error = devm_add_action_or_reset(&client->dev, exc3000_shutdown_timer,
+ &data->timer);
+ if (error)
+ return error;
+
+ error = devm_request_threaded_irq(&client->dev, client->irq,
+ NULL, exc3000_interrupt, IRQF_ONESHOT,
+ client->name, data);
+ if (error)
+ return error;
+
+ /*
+ * I²C does not have built-in recovery, so retry on failure. This
+ * ensures, that the device probe will not fail for temporary issues
+ * on the bus. This is not needed for the sysfs calls (userspace
+ * will receive the error code and can start another query) and
+ * cannot be done for touch events (but that only means loosing one
+ * or two touch events anyways).
+ */
+ for (retry = 0; retry < 3; retry++) {
+ u8 response[EXC3000_LEN_FRAME];
+
+ error = exc3000_vendor_data_request(data, (u8[]){'E'}, 1,
+ response, 1);
+ if (error > 0) {
+ dev_dbg(&client->dev, "TS Model: %s", &response[1]);
+ error = 0;
+ break;
+ }
+ dev_warn(&client->dev, "Retry %d get EETI EXC3000 model: %d\n",
+ retry + 1, error);
+ }
+
+ if (error)
+ return error;
+
+ i2c_set_clientdata(client, data);
+
+ error = devm_device_add_group(&client->dev, &exc3000_attribute_group);
+ if (error)
+ return error;
+
+ return 0;
+}
+
+static const struct i2c_device_id exc3000_id[] = {
+ { "exc3000", EETI_EXC3000 },
+ { "exc80h60", EETI_EXC80H60 },
+ { "exc80h84", EETI_EXC80H84 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, exc3000_id);
+
+#ifdef CONFIG_OF
+static const struct of_device_id exc3000_of_match[] = {
+ { .compatible = "eeti,exc3000", .data = &exc3000_info[EETI_EXC3000] },
+ { .compatible = "eeti,exc80h60", .data = &exc3000_info[EETI_EXC80H60] },
+ { .compatible = "eeti,exc80h84", .data = &exc3000_info[EETI_EXC80H84] },
+ { }
+};
+MODULE_DEVICE_TABLE(of, exc3000_of_match);
+#endif
+
+static struct i2c_driver exc3000_driver = {
+ .driver = {
+ .name = "exc3000",
+ .of_match_table = of_match_ptr(exc3000_of_match),
+ },
+ .id_table = exc3000_id,
+ .probe_new = exc3000_probe,
+};
+
+module_i2c_driver(exc3000_driver);
+
+MODULE_AUTHOR("Ahmet Inan <inan@distec.de>");
+MODULE_DESCRIPTION("I2C connected EETI EXC3000 multiple touch controller driver");
+MODULE_LICENSE("GPL v2");