1 files changed, 340 insertions, 0 deletions

diff --git a/drivers/input/touchscreen/st1232.c b/drivers/input/touchscreen/st1232.c
new file mode 100644
index 000000000..63b29c727
--- /dev/null
+++ b/drivers/input/touchscreen/st1232.c
@@ -0,0 +1,340 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ST1232 Touchscreen Controller Driver
+ *
+ * Copyright (C) 2010 Renesas Solutions Corp.
+ *	Tony SIM <chinyeow.sim.xt@renesas.com>
+ *
+ * Using code from:
+ *  - android.git.kernel.org: projects/kernel/common.git: synaptics_i2c_rmi.c
+ *	Copyright (C) 2007 Google, Inc.
+ */
+
+#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/module.h>
+#include <linux/of.h>
+#include <linux/pm_qos.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+
+#define ST1232_TS_NAME	"st1232-ts"
+#define ST1633_TS_NAME	"st1633-ts"
+
+#define ST_TS_MAX_FINGERS	10
+
+struct st_chip_info {
+	bool	have_z;
+	u16	max_x;
+	u16	max_y;
+	u16	max_area;
+	u16	max_fingers;
+	u8	start_reg;
+};
+
+struct st1232_ts_data {
+	struct i2c_client *client;
+	struct input_dev *input_dev;
+	struct touchscreen_properties prop;
+	struct dev_pm_qos_request low_latency_req;
+	struct gpio_desc *reset_gpio;
+	const struct st_chip_info *chip_info;
+	int read_buf_len;
+	u8 *read_buf;
+};
+
+static int st1232_ts_read_data(struct st1232_ts_data *ts)
+{
+	struct i2c_client *client = ts->client;
+	u8 start_reg = ts->chip_info->start_reg;
+	struct i2c_msg msg[] = {
+		{
+			.addr	= client->addr,
+			.len	= sizeof(start_reg),
+			.buf	= &start_reg,
+		},
+		{
+			.addr	= client->addr,
+			.flags	= I2C_M_RD | I2C_M_DMA_SAFE,
+			.len	= ts->read_buf_len,
+			.buf	= ts->read_buf,
+		}
+	};
+	int ret;
+
+	ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
+	if (ret != ARRAY_SIZE(msg))
+		return ret < 0 ? ret : -EIO;
+
+	return 0;
+}
+
+static int st1232_ts_parse_and_report(struct st1232_ts_data *ts)
+{
+	struct input_dev *input = ts->input_dev;
+	struct input_mt_pos pos[ST_TS_MAX_FINGERS];
+	u8 z[ST_TS_MAX_FINGERS];
+	int slots[ST_TS_MAX_FINGERS];
+	int n_contacts = 0;
+	int i;
+
+	for (i = 0; i < ts->chip_info->max_fingers; i++) {
+		u8 *buf = &ts->read_buf[i * 4];
+
+		if (buf[0] & BIT(7)) {
+			unsigned int x = ((buf[0] & 0x70) << 4) | buf[1];
+			unsigned int y = ((buf[0] & 0x07) << 8) | buf[2];
+
+			touchscreen_set_mt_pos(&pos[n_contacts],
+					       &ts->prop, x, y);
+
+			/* st1232 includes a z-axis / touch strength */
+			if (ts->chip_info->have_z)
+				z[n_contacts] = ts->read_buf[i + 6];
+
+			n_contacts++;
+		}
+	}
+
+	input_mt_assign_slots(input, slots, pos, n_contacts, 0);
+	for (i = 0; i < n_contacts; i++) {
+		input_mt_slot(input, slots[i]);
+		input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
+		input_report_abs(input, ABS_MT_POSITION_X, pos[i].x);
+		input_report_abs(input, ABS_MT_POSITION_Y, pos[i].y);
+		if (ts->chip_info->have_z)
+			input_report_abs(input, ABS_MT_TOUCH_MAJOR, z[i]);
+	}
+
+	input_mt_sync_frame(input);
+	input_sync(input);
+
+	return n_contacts;
+}
+
+static irqreturn_t st1232_ts_irq_handler(int irq, void *dev_id)
+{
+	struct st1232_ts_data *ts = dev_id;
+	int count;
+	int error;
+
+	error = st1232_ts_read_data(ts);
+	if (error)
+		goto out;
+
+	count = st1232_ts_parse_and_report(ts);
+	if (!count) {
+		if (ts->low_latency_req.dev) {
+			dev_pm_qos_remove_request(&ts->low_latency_req);
+			ts->low_latency_req.dev = NULL;
+		}
+	} else if (!ts->low_latency_req.dev) {
+		/* First contact, request 100 us latency. */
+		dev_pm_qos_add_ancestor_request(&ts->client->dev,
+						&ts->low_latency_req,
+						DEV_PM_QOS_RESUME_LATENCY, 100);
+	}
+
+out:
+	return IRQ_HANDLED;
+}
+
+static void st1232_ts_power(struct st1232_ts_data *ts, bool poweron)
+{
+	if (ts->reset_gpio)
+		gpiod_set_value_cansleep(ts->reset_gpio, !poweron);
+}
+
+static void st1232_ts_power_off(void *data)
+{
+	st1232_ts_power(data, false);
+}
+
+static const struct st_chip_info st1232_chip_info = {
+	.have_z		= true,
+	.max_x		= 0x31f, /* 800 - 1 */
+	.max_y		= 0x1df, /* 480 -1 */
+	.max_area	= 0xff,
+	.max_fingers	= 2,
+	.start_reg	= 0x12,
+};
+
+static const struct st_chip_info st1633_chip_info = {
+	.have_z		= false,
+	.max_x		= 0x13f, /* 320 - 1 */
+	.max_y		= 0x1df, /* 480 -1 */
+	.max_area	= 0x00,
+	.max_fingers	= 5,
+	.start_reg	= 0x12,
+};
+
+static int st1232_ts_probe(struct i2c_client *client,
+			   const struct i2c_device_id *id)
+{
+	const struct st_chip_info *match;
+	struct st1232_ts_data *ts;
+	struct input_dev *input_dev;
+	int error;
+
+	match = device_get_match_data(&client->dev);
+	if (!match && id)
+		match = (const void *)id->driver_data;
+	if (!match) {
+		dev_err(&client->dev, "unknown device model\n");
+		return -ENODEV;
+	}
+
+	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
+		dev_err(&client->dev, "need I2C_FUNC_I2C\n");
+		return -EIO;
+	}
+
+	if (!client->irq) {
+		dev_err(&client->dev, "no IRQ?\n");
+		return -EINVAL;
+	}
+
+	ts = devm_kzalloc(&client->dev, sizeof(*ts), GFP_KERNEL);
+	if (!ts)
+		return -ENOMEM;
+
+	ts->chip_info = match;
+
+	/* allocate a buffer according to the number of registers to read */
+	ts->read_buf_len = ts->chip_info->max_fingers * 4;
+	ts->read_buf = devm_kzalloc(&client->dev, ts->read_buf_len, GFP_KERNEL);
+	if (!ts->read_buf)
+		return -ENOMEM;
+
+	input_dev = devm_input_allocate_device(&client->dev);
+	if (!input_dev)
+		return -ENOMEM;
+
+	ts->client = client;
+	ts->input_dev = input_dev;
+
+	ts->reset_gpio = devm_gpiod_get_optional(&client->dev, NULL,
+						 GPIOD_OUT_HIGH);
+	if (IS_ERR(ts->reset_gpio)) {
+		error = PTR_ERR(ts->reset_gpio);
+		dev_err(&client->dev, "Unable to request GPIO pin: %d.\n",
+			error);
+		return error;
+	}
+
+	st1232_ts_power(ts, true);
+
+	error = devm_add_action_or_reset(&client->dev, st1232_ts_power_off, ts);
+	if (error) {
+		dev_err(&client->dev,
+			"Failed to install power off action: %d\n", error);
+		return error;
+	}
+
+	input_dev->name = "st1232-touchscreen";
+	input_dev->id.bustype = BUS_I2C;
+
+	if (ts->chip_info->have_z)
+		input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR, 0,
+				     ts->chip_info->max_area, 0, 0);
+
+	input_set_abs_params(input_dev, ABS_MT_POSITION_X,
+			     0, ts->chip_info->max_x, 0, 0);
+	input_set_abs_params(input_dev, ABS_MT_POSITION_Y,
+			     0, ts->chip_info->max_y, 0, 0);
+
+	touchscreen_parse_properties(input_dev, true, &ts->prop);
+
+	error = input_mt_init_slots(input_dev, ts->chip_info->max_fingers,
+				    INPUT_MT_DIRECT | INPUT_MT_TRACK |
+					INPUT_MT_DROP_UNUSED);
+	if (error) {
+		dev_err(&client->dev, "failed to initialize MT slots\n");
+		return error;
+	}
+
+	error = devm_request_threaded_irq(&client->dev, client->irq,
+					  NULL, st1232_ts_irq_handler,
+					  IRQF_ONESHOT,
+					  client->name, ts);
+	if (error) {
+		dev_err(&client->dev, "Failed to register interrupt\n");
+		return error;
+	}
+
+	error = input_register_device(ts->input_dev);
+	if (error) {
+		dev_err(&client->dev, "Unable to register %s input device\n",
+			input_dev->name);
+		return error;
+	}
+
+	i2c_set_clientdata(client, ts);
+
+	return 0;
+}
+
+static int __maybe_unused st1232_ts_suspend(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct st1232_ts_data *ts = i2c_get_clientdata(client);
+
+	disable_irq(client->irq);
+
+	if (!device_may_wakeup(&client->dev))
+		st1232_ts_power(ts, false);
+
+	return 0;
+}
+
+static int __maybe_unused st1232_ts_resume(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct st1232_ts_data *ts = i2c_get_clientdata(client);
+
+	if (!device_may_wakeup(&client->dev))
+		st1232_ts_power(ts, true);
+
+	enable_irq(client->irq);
+
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(st1232_ts_pm_ops,
+			 st1232_ts_suspend, st1232_ts_resume);
+
+static const struct i2c_device_id st1232_ts_id[] = {
+	{ ST1232_TS_NAME, (unsigned long)&st1232_chip_info },
+	{ ST1633_TS_NAME, (unsigned long)&st1633_chip_info },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, st1232_ts_id);
+
+static const struct of_device_id st1232_ts_dt_ids[] = {
+	{ .compatible = "sitronix,st1232", .data = &st1232_chip_info },
+	{ .compatible = "sitronix,st1633", .data = &st1633_chip_info },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, st1232_ts_dt_ids);
+
+static struct i2c_driver st1232_ts_driver = {
+	.probe		= st1232_ts_probe,
+	.id_table	= st1232_ts_id,
+	.driver = {
+		.name	= ST1232_TS_NAME,
+		.of_match_table = st1232_ts_dt_ids,
+		.pm	= &st1232_ts_pm_ops,
+	},
+};
+
+module_i2c_driver(st1232_ts_driver);
+
+MODULE_AUTHOR("Tony SIM <chinyeow.sim.xt@renesas.com>");
+MODULE_AUTHOR("Martin Kepplinger <martin.kepplinger@ginzinger.com>");
+MODULE_DESCRIPTION("SITRONIX ST1232 Touchscreen Controller Driver");
+MODULE_LICENSE("GPL v2");