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-rw-r--r--drivers/input/touchscreen/eeti_ts.c275
1 files changed, 275 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/eeti_ts.c b/drivers/input/touchscreen/eeti_ts.c
new file mode 100644
index 000000000..7fe41965c
--- /dev/null
+++ b/drivers/input/touchscreen/eeti_ts.c
@@ -0,0 +1,275 @@
+/*
+ * Touch Screen driver for EETI's I2C connected touch screen panels
+ * Copyright (c) 2009,2018 Daniel Mack <daniel@zonque.org>
+ *
+ * See EETI's software guide for the protocol specification:
+ * http://home.eeti.com.tw/documentation.html
+ *
+ * Based on migor_ts.c
+ * Copyright (c) 2008 Magnus Damm
+ * Copyright (c) 2007 Ujjwal Pande <ujjwal@kenati.com>
+ *
+ * This file is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This file is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/input.h>
+#include <linux/input/touchscreen.h>
+#include <linux/interrupt.h>
+#include <linux/i2c.h>
+#include <linux/timer.h>
+#include <linux/gpio/consumer.h>
+#include <linux/of.h>
+#include <linux/slab.h>
+#include <asm/unaligned.h>
+
+struct eeti_ts {
+ struct i2c_client *client;
+ struct input_dev *input;
+ struct gpio_desc *attn_gpio;
+ struct touchscreen_properties props;
+ bool running;
+};
+
+#define EETI_TS_BITDEPTH (11)
+#define EETI_MAXVAL ((1 << (EETI_TS_BITDEPTH + 1)) - 1)
+
+#define REPORT_BIT_PRESSED BIT(0)
+#define REPORT_BIT_AD0 BIT(1)
+#define REPORT_BIT_AD1 BIT(2)
+#define REPORT_BIT_HAS_PRESSURE BIT(6)
+#define REPORT_RES_BITS(v) (((v) >> 1) + EETI_TS_BITDEPTH)
+
+static void eeti_ts_report_event(struct eeti_ts *eeti, u8 *buf)
+{
+ unsigned int res;
+ u16 x, y;
+
+ res = REPORT_RES_BITS(buf[0] & (REPORT_BIT_AD0 | REPORT_BIT_AD1));
+
+ x = get_unaligned_be16(&buf[1]);
+ y = get_unaligned_be16(&buf[3]);
+
+ /* fix the range to 11 bits */
+ x >>= res - EETI_TS_BITDEPTH;
+ y >>= res - EETI_TS_BITDEPTH;
+
+ if (buf[0] & REPORT_BIT_HAS_PRESSURE)
+ input_report_abs(eeti->input, ABS_PRESSURE, buf[5]);
+
+ touchscreen_report_pos(eeti->input, &eeti->props, x, y, false);
+ input_report_key(eeti->input, BTN_TOUCH, buf[0] & REPORT_BIT_PRESSED);
+ input_sync(eeti->input);
+}
+
+static irqreturn_t eeti_ts_isr(int irq, void *dev_id)
+{
+ struct eeti_ts *eeti = dev_id;
+ int len;
+ int error;
+ char buf[6];
+
+ do {
+ len = i2c_master_recv(eeti->client, buf, sizeof(buf));
+ if (len != sizeof(buf)) {
+ error = len < 0 ? len : -EIO;
+ dev_err(&eeti->client->dev,
+ "failed to read touchscreen data: %d\n",
+ error);
+ break;
+ }
+
+ if (buf[0] & 0x80) {
+ /* Motion packet */
+ eeti_ts_report_event(eeti, buf);
+ }
+ } while (eeti->running &&
+ eeti->attn_gpio && gpiod_get_value_cansleep(eeti->attn_gpio));
+
+ return IRQ_HANDLED;
+}
+
+static void eeti_ts_start(struct eeti_ts *eeti)
+{
+ eeti->running = true;
+ wmb();
+ enable_irq(eeti->client->irq);
+}
+
+static void eeti_ts_stop(struct eeti_ts *eeti)
+{
+ eeti->running = false;
+ wmb();
+ disable_irq(eeti->client->irq);
+}
+
+static int eeti_ts_open(struct input_dev *dev)
+{
+ struct eeti_ts *eeti = input_get_drvdata(dev);
+
+ eeti_ts_start(eeti);
+
+ return 0;
+}
+
+static void eeti_ts_close(struct input_dev *dev)
+{
+ struct eeti_ts *eeti = input_get_drvdata(dev);
+
+ eeti_ts_stop(eeti);
+}
+
+static int eeti_ts_probe(struct i2c_client *client,
+ const struct i2c_device_id *idp)
+{
+ struct device *dev = &client->dev;
+ struct eeti_ts *eeti;
+ struct input_dev *input;
+ int error;
+
+ /*
+ * In contrast to what's described in the datasheet, there seems
+ * to be no way of probing the presence of that device using I2C
+ * commands. So we need to blindly believe it is there, and wait
+ * for interrupts to occur.
+ */
+
+ eeti = devm_kzalloc(dev, sizeof(*eeti), GFP_KERNEL);
+ if (!eeti) {
+ dev_err(dev, "failed to allocate driver data\n");
+ return -ENOMEM;
+ }
+
+ input = devm_input_allocate_device(dev);
+ if (!input) {
+ dev_err(dev, "Failed to allocate input device.\n");
+ return -ENOMEM;
+ }
+
+ input_set_capability(input, EV_KEY, BTN_TOUCH);
+
+ input_set_abs_params(input, ABS_X, 0, EETI_MAXVAL, 0, 0);
+ input_set_abs_params(input, ABS_Y, 0, EETI_MAXVAL, 0, 0);
+ input_set_abs_params(input, ABS_PRESSURE, 0, 0xff, 0, 0);
+
+ touchscreen_parse_properties(input, false, &eeti->props);
+
+ input->name = client->name;
+ input->id.bustype = BUS_I2C;
+ input->open = eeti_ts_open;
+ input->close = eeti_ts_close;
+
+ eeti->client = client;
+ eeti->input = input;
+
+ eeti->attn_gpio = devm_gpiod_get_optional(dev, "attn", GPIOD_IN);
+ if (IS_ERR(eeti->attn_gpio))
+ return PTR_ERR(eeti->attn_gpio);
+
+ i2c_set_clientdata(client, eeti);
+ input_set_drvdata(input, eeti);
+
+ error = devm_request_threaded_irq(dev, client->irq,
+ NULL, eeti_ts_isr,
+ IRQF_ONESHOT,
+ client->name, eeti);
+ if (error) {
+ dev_err(dev, "Unable to request touchscreen IRQ: %d\n",
+ error);
+ return error;
+ }
+
+ /*
+ * Disable the device for now. It will be enabled once the
+ * input device is opened.
+ */
+ eeti_ts_stop(eeti);
+
+ error = input_register_device(input);
+ if (error)
+ return error;
+
+ return 0;
+}
+
+static int __maybe_unused eeti_ts_suspend(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct eeti_ts *eeti = i2c_get_clientdata(client);
+ struct input_dev *input_dev = eeti->input;
+
+ mutex_lock(&input_dev->mutex);
+
+ if (input_dev->users)
+ eeti_ts_stop(eeti);
+
+ mutex_unlock(&input_dev->mutex);
+
+ if (device_may_wakeup(&client->dev))
+ enable_irq_wake(client->irq);
+
+ return 0;
+}
+
+static int __maybe_unused eeti_ts_resume(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct eeti_ts *eeti = i2c_get_clientdata(client);
+ struct input_dev *input_dev = eeti->input;
+
+ if (device_may_wakeup(&client->dev))
+ disable_irq_wake(client->irq);
+
+ mutex_lock(&input_dev->mutex);
+
+ if (input_dev->users)
+ eeti_ts_start(eeti);
+
+ mutex_unlock(&input_dev->mutex);
+
+ return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(eeti_ts_pm, eeti_ts_suspend, eeti_ts_resume);
+
+static const struct i2c_device_id eeti_ts_id[] = {
+ { "eeti_ts", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, eeti_ts_id);
+
+#ifdef CONFIG_OF
+static const struct of_device_id of_eeti_ts_match[] = {
+ { .compatible = "eeti,exc3000-i2c", },
+ { }
+};
+#endif
+
+static struct i2c_driver eeti_ts_driver = {
+ .driver = {
+ .name = "eeti_ts",
+ .pm = &eeti_ts_pm,
+ .of_match_table = of_match_ptr(of_eeti_ts_match),
+ },
+ .probe = eeti_ts_probe,
+ .id_table = eeti_ts_id,
+};
+
+module_i2c_driver(eeti_ts_driver);
+
+MODULE_DESCRIPTION("EETI Touchscreen driver");
+MODULE_AUTHOR("Daniel Mack <daniel@zonque.org>");
+MODULE_LICENSE("GPL");
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-27 18:12:18 +0000