1 files changed, 628 insertions, 0 deletions

diff --git a/drivers/input/touchscreen/pixcir_i2c_ts.c b/drivers/input/touchscreen/pixcir_i2c_ts.c
new file mode 100644
index 000000000..9aa098577
--- /dev/null
+++ b/drivers/input/touchscreen/pixcir_i2c_ts.c
@@ -0,0 +1,628 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Driver for Pixcir I2C touchscreen controllers.
+ *
+ * Copyright (C) 2010-2011 Pixcir, Inc.
+ */
+
+#include <asm/unaligned.h>
+#include <linux/delay.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/of_device.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+
+#define PIXCIR_MAX_SLOTS       5 /* Max fingers supported by driver */
+
+/*
+ * Register map
+ */
+#define PIXCIR_REG_POWER_MODE	51
+#define PIXCIR_REG_INT_MODE	52
+
+/*
+ * Power modes:
+ * active: max scan speed
+ * idle: lower scan speed with automatic transition to active on touch
+ * halt: datasheet says sleep but this is more like halt as the chip
+ *       clocks are cut and it can only be brought out of this mode
+ *	 using the RESET pin.
+ */
+enum pixcir_power_mode {
+	PIXCIR_POWER_ACTIVE,
+	PIXCIR_POWER_IDLE,
+	PIXCIR_POWER_HALT,
+};
+
+#define PIXCIR_POWER_MODE_MASK	0x03
+#define PIXCIR_POWER_ALLOW_IDLE (1UL << 2)
+
+/*
+ * Interrupt modes:
+ * periodical: interrupt is asserted periodicaly
+ * diff coordinates: interrupt is asserted when coordinates change
+ * level on touch: interrupt level asserted during touch
+ * pulse on touch: interrupt pulse asserted during touch
+ *
+ */
+enum pixcir_int_mode {
+	PIXCIR_INT_PERIODICAL,
+	PIXCIR_INT_DIFF_COORD,
+	PIXCIR_INT_LEVEL_TOUCH,
+	PIXCIR_INT_PULSE_TOUCH,
+};
+
+#define PIXCIR_INT_MODE_MASK	0x03
+#define PIXCIR_INT_ENABLE	(1UL << 3)
+#define PIXCIR_INT_POL_HIGH	(1UL << 2)
+
+/**
+ * struct pixcir_i2c_chip_data - chip related data
+ * @max_fingers:	Max number of fingers reported simultaneously by h/w
+ * @has_hw_ids:		Hardware supports finger tracking IDs
+ *
+ */
+struct pixcir_i2c_chip_data {
+	u8 max_fingers;
+	bool has_hw_ids;
+};
+
+struct pixcir_i2c_ts_data {
+	struct i2c_client *client;
+	struct input_dev *input;
+	struct gpio_desc *gpio_attb;
+	struct gpio_desc *gpio_reset;
+	struct gpio_desc *gpio_enable;
+	struct gpio_desc *gpio_wake;
+	const struct pixcir_i2c_chip_data *chip;
+	struct touchscreen_properties prop;
+	bool running;
+};
+
+struct pixcir_report_data {
+	int num_touches;
+	struct input_mt_pos pos[PIXCIR_MAX_SLOTS];
+	int ids[PIXCIR_MAX_SLOTS];
+};
+
+static void pixcir_ts_parse(struct pixcir_i2c_ts_data *tsdata,
+			    struct pixcir_report_data *report)
+{
+	u8 rdbuf[2 + PIXCIR_MAX_SLOTS * 5];
+	u8 wrbuf[1] = { 0 };
+	u8 *bufptr;
+	u8 touch;
+	int ret, i;
+	int readsize;
+	const struct pixcir_i2c_chip_data *chip = tsdata->chip;
+
+	memset(report, 0, sizeof(struct pixcir_report_data));
+
+	i = chip->has_hw_ids ? 1 : 0;
+	readsize = 2 + tsdata->chip->max_fingers * (4 + i);
+	if (readsize > sizeof(rdbuf))
+		readsize = sizeof(rdbuf);
+
+	ret = i2c_master_send(tsdata->client, wrbuf, sizeof(wrbuf));
+	if (ret != sizeof(wrbuf)) {
+		dev_err(&tsdata->client->dev,
+			"%s: i2c_master_send failed(), ret=%d\n",
+			__func__, ret);
+		return;
+	}
+
+	ret = i2c_master_recv(tsdata->client, rdbuf, readsize);
+	if (ret != readsize) {
+		dev_err(&tsdata->client->dev,
+			"%s: i2c_master_recv failed(), ret=%d\n",
+			__func__, ret);
+		return;
+	}
+
+	touch = rdbuf[0] & 0x7;
+	if (touch > tsdata->chip->max_fingers)
+		touch = tsdata->chip->max_fingers;
+
+	report->num_touches = touch;
+	bufptr = &rdbuf[2];
+
+	for (i = 0; i < touch; i++) {
+		touchscreen_set_mt_pos(&report->pos[i], &tsdata->prop,
+				       get_unaligned_le16(bufptr),
+				       get_unaligned_le16(bufptr + 2));
+		if (chip->has_hw_ids) {
+			report->ids[i] = bufptr[4];
+			bufptr = bufptr + 5;
+		} else {
+			bufptr = bufptr + 4;
+		}
+	}
+}
+
+static void pixcir_ts_report(struct pixcir_i2c_ts_data *ts,
+			     struct pixcir_report_data *report)
+{
+	int slots[PIXCIR_MAX_SLOTS];
+	int n, i, slot;
+	struct device *dev = &ts->client->dev;
+	const struct pixcir_i2c_chip_data *chip = ts->chip;
+
+	n = report->num_touches;
+	if (n > PIXCIR_MAX_SLOTS)
+		n = PIXCIR_MAX_SLOTS;
+
+	if (!ts->chip->has_hw_ids)
+		input_mt_assign_slots(ts->input, slots, report->pos, n, 0);
+
+	for (i = 0; i < n; i++) {
+		if (chip->has_hw_ids) {
+			slot = input_mt_get_slot_by_key(ts->input,
+							report->ids[i]);
+			if (slot < 0) {
+				dev_dbg(dev, "no free slot for id 0x%x\n",
+					report->ids[i]);
+				continue;
+			}
+		} else {
+			slot = slots[i];
+		}
+
+		input_mt_slot(ts->input, slot);
+		input_mt_report_slot_state(ts->input, MT_TOOL_FINGER, true);
+
+		input_report_abs(ts->input, ABS_MT_POSITION_X,
+				 report->pos[i].x);
+		input_report_abs(ts->input, ABS_MT_POSITION_Y,
+				 report->pos[i].y);
+
+		dev_dbg(dev, "%d: slot %d, x %d, y %d\n",
+			i, slot, report->pos[i].x, report->pos[i].y);
+	}
+
+	input_mt_sync_frame(ts->input);
+	input_sync(ts->input);
+}
+
+static irqreturn_t pixcir_ts_isr(int irq, void *dev_id)
+{
+	struct pixcir_i2c_ts_data *tsdata = dev_id;
+	struct pixcir_report_data report;
+
+	while (tsdata->running) {
+		/* parse packet */
+		pixcir_ts_parse(tsdata, &report);
+
+		/* report it */
+		pixcir_ts_report(tsdata, &report);
+
+		if (gpiod_get_value_cansleep(tsdata->gpio_attb)) {
+			if (report.num_touches) {
+				/*
+				 * Last report with no finger up?
+				 * Do it now then.
+				 */
+				input_mt_sync_frame(tsdata->input);
+				input_sync(tsdata->input);
+			}
+			break;
+		}
+
+		msleep(20);
+	}
+
+	return IRQ_HANDLED;
+}
+
+static void pixcir_reset(struct pixcir_i2c_ts_data *tsdata)
+{
+	if (!IS_ERR_OR_NULL(tsdata->gpio_reset)) {
+		gpiod_set_value_cansleep(tsdata->gpio_reset, 1);
+		ndelay(100);	/* datasheet section 1.2.3 says 80ns min. */
+		gpiod_set_value_cansleep(tsdata->gpio_reset, 0);
+		/* wait for controller ready. 100ms guess. */
+		msleep(100);
+	}
+}
+
+static int pixcir_set_power_mode(struct pixcir_i2c_ts_data *ts,
+				 enum pixcir_power_mode mode)
+{
+	struct device *dev = &ts->client->dev;
+	int ret;
+
+	if (mode == PIXCIR_POWER_ACTIVE || mode == PIXCIR_POWER_IDLE) {
+		if (ts->gpio_wake)
+			gpiod_set_value_cansleep(ts->gpio_wake, 1);
+	}
+
+	ret = i2c_smbus_read_byte_data(ts->client, PIXCIR_REG_POWER_MODE);
+	if (ret < 0) {
+		dev_err(dev, "%s: can't read reg %d : %d\n",
+			__func__, PIXCIR_REG_POWER_MODE, ret);
+		return ret;
+	}
+
+	ret &= ~PIXCIR_POWER_MODE_MASK;
+	ret |= mode;
+
+	/* Always AUTO_IDLE */
+	ret |= PIXCIR_POWER_ALLOW_IDLE;
+
+	ret = i2c_smbus_write_byte_data(ts->client, PIXCIR_REG_POWER_MODE, ret);
+	if (ret < 0) {
+		dev_err(dev, "%s: can't write reg %d : %d\n",
+			__func__, PIXCIR_REG_POWER_MODE, ret);
+		return ret;
+	}
+
+	if (mode == PIXCIR_POWER_HALT) {
+		if (ts->gpio_wake)
+			gpiod_set_value_cansleep(ts->gpio_wake, 0);
+	}
+
+	return 0;
+}
+
+/*
+ * Set the interrupt mode for the device i.e. ATTB line behaviour
+ *
+ * @polarity : 1 for active high, 0 for active low.
+ */
+static int pixcir_set_int_mode(struct pixcir_i2c_ts_data *ts,
+			       enum pixcir_int_mode mode, bool polarity)
+{
+	struct device *dev = &ts->client->dev;
+	int ret;
+
+	ret = i2c_smbus_read_byte_data(ts->client, PIXCIR_REG_INT_MODE);
+	if (ret < 0) {
+		dev_err(dev, "%s: can't read reg %d : %d\n",
+			__func__, PIXCIR_REG_INT_MODE, ret);
+		return ret;
+	}
+
+	ret &= ~PIXCIR_INT_MODE_MASK;
+	ret |= mode;
+
+	if (polarity)
+		ret |= PIXCIR_INT_POL_HIGH;
+	else
+		ret &= ~PIXCIR_INT_POL_HIGH;
+
+	ret = i2c_smbus_write_byte_data(ts->client, PIXCIR_REG_INT_MODE, ret);
+	if (ret < 0) {
+		dev_err(dev, "%s: can't write reg %d : %d\n",
+			__func__, PIXCIR_REG_INT_MODE, ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+/*
+ * Enable/disable interrupt generation
+ */
+static int pixcir_int_enable(struct pixcir_i2c_ts_data *ts, bool enable)
+{
+	struct device *dev = &ts->client->dev;
+	int ret;
+
+	ret = i2c_smbus_read_byte_data(ts->client, PIXCIR_REG_INT_MODE);
+	if (ret < 0) {
+		dev_err(dev, "%s: can't read reg %d : %d\n",
+			__func__, PIXCIR_REG_INT_MODE, ret);
+		return ret;
+	}
+
+	if (enable)
+		ret |= PIXCIR_INT_ENABLE;
+	else
+		ret &= ~PIXCIR_INT_ENABLE;
+
+	ret = i2c_smbus_write_byte_data(ts->client, PIXCIR_REG_INT_MODE, ret);
+	if (ret < 0) {
+		dev_err(dev, "%s: can't write reg %d : %d\n",
+			__func__, PIXCIR_REG_INT_MODE, ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int pixcir_start(struct pixcir_i2c_ts_data *ts)
+{
+	struct device *dev = &ts->client->dev;
+	int error;
+
+	if (ts->gpio_enable) {
+		gpiod_set_value_cansleep(ts->gpio_enable, 1);
+		msleep(100);
+	}
+
+	/* LEVEL_TOUCH interrupt with active low polarity */
+	error = pixcir_set_int_mode(ts, PIXCIR_INT_LEVEL_TOUCH, 0);
+	if (error) {
+		dev_err(dev, "Failed to set interrupt mode: %d\n", error);
+		return error;
+	}
+
+	ts->running = true;
+	mb();	/* Update status before IRQ can fire */
+
+	/* enable interrupt generation */
+	error = pixcir_int_enable(ts, true);
+	if (error) {
+		dev_err(dev, "Failed to enable interrupt generation: %d\n",
+			error);
+		return error;
+	}
+
+	return 0;
+}
+
+static int pixcir_stop(struct pixcir_i2c_ts_data *ts)
+{
+	int error;
+
+	/* Disable interrupt generation */
+	error = pixcir_int_enable(ts, false);
+	if (error) {
+		dev_err(&ts->client->dev,
+			"Failed to disable interrupt generation: %d\n",
+			error);
+		return error;
+	}
+
+	/* Exit ISR if running, no more report parsing */
+	ts->running = false;
+	mb();	/* update status before we synchronize irq */
+
+	/* Wait till running ISR is complete */
+	synchronize_irq(ts->client->irq);
+
+	if (ts->gpio_enable)
+		gpiod_set_value_cansleep(ts->gpio_enable, 0);
+
+	return 0;
+}
+
+static int pixcir_input_open(struct input_dev *dev)
+{
+	struct pixcir_i2c_ts_data *ts = input_get_drvdata(dev);
+
+	return pixcir_start(ts);
+}
+
+static void pixcir_input_close(struct input_dev *dev)
+{
+	struct pixcir_i2c_ts_data *ts = input_get_drvdata(dev);
+
+	pixcir_stop(ts);
+}
+
+static int __maybe_unused pixcir_i2c_ts_suspend(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct pixcir_i2c_ts_data *ts = i2c_get_clientdata(client);
+	struct input_dev *input = ts->input;
+	int ret = 0;
+
+	mutex_lock(&input->mutex);
+
+	if (device_may_wakeup(&client->dev)) {
+		if (!input->users) {
+			ret = pixcir_start(ts);
+			if (ret) {
+				dev_err(dev, "Failed to start\n");
+				goto unlock;
+			}
+		}
+	} else if (input->users) {
+		ret = pixcir_stop(ts);
+	}
+
+unlock:
+	mutex_unlock(&input->mutex);
+
+	return ret;
+}
+
+static int __maybe_unused pixcir_i2c_ts_resume(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct pixcir_i2c_ts_data *ts = i2c_get_clientdata(client);
+	struct input_dev *input = ts->input;
+	int ret = 0;
+
+	mutex_lock(&input->mutex);
+
+	if (device_may_wakeup(&client->dev)) {
+		if (!input->users) {
+			ret = pixcir_stop(ts);
+			if (ret) {
+				dev_err(dev, "Failed to stop\n");
+				goto unlock;
+			}
+		}
+	} else if (input->users) {
+		ret = pixcir_start(ts);
+	}
+
+unlock:
+	mutex_unlock(&input->mutex);
+
+	return ret;
+}
+
+static SIMPLE_DEV_PM_OPS(pixcir_dev_pm_ops,
+			 pixcir_i2c_ts_suspend, pixcir_i2c_ts_resume);
+
+static int pixcir_i2c_ts_probe(struct i2c_client *client,
+			       const struct i2c_device_id *id)
+{
+	struct device *dev = &client->dev;
+	struct pixcir_i2c_ts_data *tsdata;
+	struct input_dev *input;
+	int error;
+
+	tsdata = devm_kzalloc(dev, sizeof(*tsdata), GFP_KERNEL);
+	if (!tsdata)
+		return -ENOMEM;
+
+	tsdata->chip = device_get_match_data(dev);
+	if (!tsdata->chip && id)
+		tsdata->chip = (const void *)id->driver_data;
+	if (!tsdata->chip) {
+		dev_err(dev, "can't locate chip data\n");
+		return -EINVAL;
+	}
+
+	input = devm_input_allocate_device(dev);
+	if (!input) {
+		dev_err(dev, "Failed to allocate input device\n");
+		return -ENOMEM;
+	}
+
+	tsdata->client = client;
+	tsdata->input = input;
+
+	input->name = client->name;
+	input->id.bustype = BUS_I2C;
+	input->open = pixcir_input_open;
+	input->close = pixcir_input_close;
+
+	input_set_capability(input, EV_ABS, ABS_MT_POSITION_X);
+	input_set_capability(input, EV_ABS, ABS_MT_POSITION_Y);
+	touchscreen_parse_properties(input, true, &tsdata->prop);
+	if (!input_abs_get_max(input, ABS_MT_POSITION_X) ||
+	    !input_abs_get_max(input, ABS_MT_POSITION_Y)) {
+		dev_err(dev, "Touchscreen size is not specified\n");
+		return -EINVAL;
+	}
+
+	error = input_mt_init_slots(input, tsdata->chip->max_fingers,
+				    INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
+	if (error) {
+		dev_err(dev, "Error initializing Multi-Touch slots\n");
+		return error;
+	}
+
+	input_set_drvdata(input, tsdata);
+
+	tsdata->gpio_attb = devm_gpiod_get(dev, "attb", GPIOD_IN);
+	if (IS_ERR(tsdata->gpio_attb)) {
+		error = PTR_ERR(tsdata->gpio_attb);
+		if (error != -EPROBE_DEFER)
+			dev_err(dev, "Failed to request ATTB gpio: %d\n",
+				error);
+		return error;
+	}
+
+	tsdata->gpio_reset = devm_gpiod_get_optional(dev, "reset",
+						     GPIOD_OUT_LOW);
+	if (IS_ERR(tsdata->gpio_reset)) {
+		error = PTR_ERR(tsdata->gpio_reset);
+		if (error != -EPROBE_DEFER)
+			dev_err(dev, "Failed to request RESET gpio: %d\n",
+				error);
+		return error;
+	}
+
+	tsdata->gpio_wake = devm_gpiod_get_optional(dev, "wake",
+						    GPIOD_OUT_HIGH);
+	if (IS_ERR(tsdata->gpio_wake)) {
+		error = PTR_ERR(tsdata->gpio_wake);
+		if (error != -EPROBE_DEFER)
+			dev_err(dev, "Failed to get wake gpio: %d\n", error);
+		return error;
+	}
+
+	tsdata->gpio_enable = devm_gpiod_get_optional(dev, "enable",
+						      GPIOD_OUT_HIGH);
+	if (IS_ERR(tsdata->gpio_enable)) {
+		error = PTR_ERR(tsdata->gpio_enable);
+		if (error != -EPROBE_DEFER)
+			dev_err(dev, "Failed to get enable gpio: %d\n", error);
+		return error;
+	}
+
+	if (tsdata->gpio_enable)
+		msleep(100);
+
+	error = devm_request_threaded_irq(dev, client->irq, NULL, pixcir_ts_isr,
+					  IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+					  client->name, tsdata);
+	if (error) {
+		dev_err(dev, "failed to request irq %d\n", client->irq);
+		return error;
+	}
+
+	pixcir_reset(tsdata);
+
+	/* Always be in IDLE mode to save power, device supports auto wake */
+	error = pixcir_set_power_mode(tsdata, PIXCIR_POWER_IDLE);
+	if (error) {
+		dev_err(dev, "Failed to set IDLE mode\n");
+		return error;
+	}
+
+	/* Stop device till opened */
+	error = pixcir_stop(tsdata);
+	if (error)
+		return error;
+
+	error = input_register_device(input);
+	if (error)
+		return error;
+
+	i2c_set_clientdata(client, tsdata);
+
+	return 0;
+}
+
+static const struct pixcir_i2c_chip_data pixcir_ts_data = {
+	.max_fingers = 2,
+	/* no hw id support */
+};
+
+static const struct pixcir_i2c_chip_data pixcir_tangoc_data = {
+	.max_fingers = 5,
+	.has_hw_ids = true,
+};
+
+static const struct i2c_device_id pixcir_i2c_ts_id[] = {
+	{ "pixcir_ts", (unsigned long) &pixcir_ts_data },
+	{ "pixcir_tangoc", (unsigned long) &pixcir_tangoc_data },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, pixcir_i2c_ts_id);
+
+#ifdef CONFIG_OF
+static const struct of_device_id pixcir_of_match[] = {
+	{ .compatible = "pixcir,pixcir_ts", .data = &pixcir_ts_data },
+	{ .compatible = "pixcir,pixcir_tangoc", .data = &pixcir_tangoc_data },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, pixcir_of_match);
+#endif
+
+static struct i2c_driver pixcir_i2c_ts_driver = {
+	.driver = {
+		.name	= "pixcir_ts",
+		.pm	= &pixcir_dev_pm_ops,
+		.of_match_table = of_match_ptr(pixcir_of_match),
+	},
+	.probe		= pixcir_i2c_ts_probe,
+	.id_table	= pixcir_i2c_ts_id,
+};
+
+module_i2c_driver(pixcir_i2c_ts_driver);
+
+MODULE_AUTHOR("Jianchun Bian <jcbian@pixcir.com.cn>, Dequan Meng <dqmeng@pixcir.com.cn>");
+MODULE_DESCRIPTION("Pixcir I2C Touchscreen Driver");
+MODULE_LICENSE("GPL");