[2/2,v4] Input: cy8ctma140 - add driver

diff --git a/MAINTAINERS b/MAINTAINERS
index e64e5db31497..1912de113237 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4655,6 +4655,12 @@  Q:	http://patchwork.linuxtv.org/project/linux-media/list/
 T:	git git://linuxtv.org/anttip/media_tree.git
 F:	drivers/media/common/cypress_firmware*
 
+CYPRESS CY8CTMA140 TOUCHSCREEN DRIVER
+M:	Linus Walleij <linus.walleij@linaro.org>
+L:	linux-input@vger.kernel.org
+S:	Maintained
+F:	drivers/input/touchscreen/cy8ctma140.c
+
 CYTTSP TOUCHSCREEN DRIVER
 M:	Ferruh Yigit <fery@cypress.com>
 L:	linux-input@vger.kernel.org
diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
index c071f7c407b6..279b96d1761a 100644
--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig
@@ -214,6 +214,19 @@  config TOUCHSCREEN_CY8CTMG110
 	  To compile this driver as a module, choose M here: the
 	  module will be called cy8ctmg110_ts.
 
+config TOUCHSCREEN_CY8CTMA140
+	tristate "cy8ctma140 touchscreen"
+	depends on I2C
+	depends on GPIOLIB || COMPILE_TEST
+	help
+	  Say Y here if you have a Cypress CY8CTMA140 capacitive
+	  touchscreen also just known as "TMA140"
+
+	  If unsure, say N.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called cy8ctma140.
+
 config TOUCHSCREEN_CYTTSP_CORE
 	tristate "Cypress TTSP touchscreen"
 	help
diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile
index 94c6162409b3..006444c8f87b 100644
--- a/drivers/input/touchscreen/Makefile
+++ b/drivers/input/touchscreen/Makefile
@@ -23,6 +23,7 @@  obj-$(CONFIG_TOUCHSCREEN_BU21029)	+= bu21029_ts.o
 obj-$(CONFIG_TOUCHSCREEN_CHIPONE_ICN8318)	+= chipone_icn8318.o
 obj-$(CONFIG_TOUCHSCREEN_CHIPONE_ICN8505)	+= chipone_icn8505.o
 obj-$(CONFIG_TOUCHSCREEN_CY8CTMG110)	+= cy8ctmg110_ts.o
+obj-$(CONFIG_TOUCHSCREEN_CY8CTMA140)	+= cy8ctma140.o
 obj-$(CONFIG_TOUCHSCREEN_CYTTSP_CORE)	+= cyttsp_core.o
 obj-$(CONFIG_TOUCHSCREEN_CYTTSP_I2C)	+= cyttsp_i2c.o cyttsp_i2c_common.o
 obj-$(CONFIG_TOUCHSCREEN_CYTTSP_SPI)	+= cyttsp_spi.o
diff --git a/drivers/input/touchscreen/cy8ctma140.c b/drivers/input/touchscreen/cy8ctma140.c
new file mode 100644
index 000000000000..12ceec1e306b
--- /dev/null
+++ b/drivers/input/touchscreen/cy8ctma140.c
@@ -0,0 +1,406 @@ 
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Driver for Cypress CY8CTMA140 (TMA140) touchscreen
+ * (C) 2020 Linus Walleij <linus.walleij@linaro.org>
+ * (C) 2007 Cypress
+ * (C) 2007 Google, Inc.
+ *
+ * Inspired by the tma140_skomer.c driver in the Samsung GT-S7710 code
+ * drop. The GT-S7710 is codenamed "Skomer", the code also indicates
+ * that the same touchscreen was used in a product called "Lucas".
+ *
+ * The code drop for GT-S7710 also contains a firmware downloader and
+ * 15 (!) versions of the firmware drop from Cypress. But here we assume
+ * the firmware got downloaded to the touchscreen flash successfully and
+ * just use it to read the fingers. The shipped vendor driver does the
+ * same.
+ */
+
+#include <asm/unaligned.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/input.h>
+#include <linux/input/touchscreen.h>
+#include <linux/input/mt.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/i2c.h>
+#include <linux/regulator/consumer.h>
+#include <linux/delay.h>
+
+/* Used for driver name etc */
+#define CY8CTMA140_NAME "cy8ctma140"
+
+/*
+ * The datasheet claims the device supports 4 fingers but the firmware
+ * I've seen certainly only supports 2 fingers.
+ */
+#define CY8CTMA140_MAX_FINGERS 2
+#define CY8CTMA140_GET_FINGERS 0x00
+#define CY8CTMA140_GET_FW_INFO 0x19
+
+struct cy8ctma140 {
+	struct input_dev *input;
+	struct touchscreen_properties props;
+	struct device *dev;
+	struct i2c_client *client;
+	struct regulator_bulk_data regulators[2];
+	u8 prev_fingers;
+	u8 prev_f1id;
+	u8 prev_f2id;
+};
+
+static irqreturn_t cy8ctma140_irq_thread(int irq, void *d)
+{
+	struct cy8ctma140 *ts = d;
+	u8 msgbuf0[1];
+	/* This message also fits some bytes for touchkeys, if used */
+	u8 buf[31];
+	struct i2c_msg msg[] = {
+		{
+			.addr = ts->client->addr,
+			.flags = 0,
+			.len = 1,
+			.buf = msgbuf0,
+		}, {
+			.addr = ts->client->addr,
+			.flags = I2C_M_RD,
+			.len = sizeof(buf),
+			.buf = buf,
+		},
+	};
+	u8 fingers;
+	/* X, Y and Width (W) supported */
+	u16 f1x, f1y;
+	u16 f2x, f2y;
+	u8 f1w, f2w;
+	u8 f1id, f2id;
+	int ret;
+	struct input_mt_pos pos;
+
+	msgbuf0[0] = CY8CTMA140_GET_FINGERS;
+	ret = __i2c_transfer(ts->client->adapter, msg, ARRAY_SIZE(msg));
+	if (ret < 0) {
+		dev_err(ts->dev, "error reading message\n");
+		goto evt_out;
+	}
+	if (ret != ARRAY_SIZE(msg)) {
+		dev_err(ts->dev, "wrong number of messages\n");
+		goto evt_out;
+	}
+	if (buf[1] & 0x20) {
+		dev_info(ts->dev, "invalid event\n");
+		goto evt_out;
+	}
+
+	/* IDs are 1 and 2 so subtract 1 from ID */
+	f1id = (buf[8] >> 4) - 1;
+	f2id = (buf[8] & 0x0f) - 1;
+
+	f1x = get_unaligned_be16(&buf[3]);
+	f1y = get_unaligned_be16(&buf[5]);
+	f1w = buf[7];
+
+	f2x = get_unaligned_be16(&buf[9]);
+	f2y = get_unaligned_be16(&buf[11]);
+	f2w = buf[13];
+
+	fingers = buf[2] & 0x0f;
+
+	if (!fingers) {
+		/*
+		 * For the unlikely case that both fingers reports as released
+		 * by the same IRQ.
+		 */
+		if (ts->prev_fingers >= 2) {
+			dev_dbg(ts->dev, "release finger 2 ID: %02x\n",
+				ts->prev_f2id);
+			input_mt_slot(ts->input, ts->prev_f2id);
+			input_mt_report_slot_state(ts->input, MT_TOOL_FINGER,
+						   false);
+		}
+		if (ts->prev_fingers >= 1) {
+			dev_dbg(ts->dev, "release finger 1 ID: %02x\n",
+				ts->prev_f1id);
+			input_mt_slot(ts->input, ts->prev_f1id);
+			input_mt_report_slot_state(ts->input,
+						   MT_TOOL_FINGER, false);
+		}
+		goto fingers_out;
+	}
+
+	/*
+	 * When just handling two fingers this code is simple and we do not
+	 * need a loop increasing the complexity. If you need to modify
+	 * this driver for some firmware handling more than 2 fingers,
+	 * this is where you put in an array of coordinates and a loop
+	 * instead.
+	 */
+	if (fingers >= 1) {
+		touchscreen_set_mt_pos(&pos, &ts->props, f1x, f1y);
+		dev_dbg(ts->dev,
+			"%d fingers: finger 1 ID: %02x (%d, %d) w: %d\n",
+			fingers, f1id, pos.x, pos.y, f1w);
+		input_mt_slot(ts->input, f1id);
+		input_mt_report_slot_state(ts->input, MT_TOOL_FINGER, true);
+		input_report_abs(ts->input, ABS_MT_POSITION_X, pos.x);
+		input_report_abs(ts->input, ABS_MT_POSITION_Y, pos.y);
+		input_report_abs(ts->input, ABS_MT_TOUCH_MAJOR, f1w);
+	}
+	if (fingers == 1 && ts->prev_fingers == 2) {
+		dev_dbg(ts->dev, "release finger 2 ID: %02x\n", ts->prev_f2id);
+		input_mt_slot(ts->input, ts->prev_f2id);
+		input_mt_report_slot_state(ts->input, MT_TOOL_FINGER, false);
+		goto fingers_out;
+	}
+	if (fingers >= 2) {
+		touchscreen_set_mt_pos(&pos, &ts->props, f2x, f2y);
+		dev_dbg(ts->dev,
+			"%d fingers: finger 2 ID %02x (%d, %d) w: %d\n",
+			fingers, f2id, pos.x, pos.y, f2w);
+		input_mt_slot(ts->input, f2id);
+		input_mt_report_slot_state(ts->input, MT_TOOL_FINGER, true);
+		input_report_abs(ts->input, ABS_MT_POSITION_X, pos.x);
+		input_report_abs(ts->input, ABS_MT_POSITION_Y, pos.y);
+		input_report_abs(ts->input, ABS_MT_TOUCH_MAJOR, f2w);
+	}
+	if (fingers > 2)
+		dev_err(ts->dev, "%d fingers - unsupported!\n", fingers);
+
+fingers_out:
+	input_mt_sync_frame(ts->input);
+	input_sync(ts->input);
+	/*
+	 * The firmware just resports 1 or 0 finger without any indication of
+	 * the ID of the finger that just disappeared, so we need to cache
+	 * the previous finger IDs.
+	 */
+	ts->prev_fingers = fingers;
+	ts->prev_f1id = f1id;
+	ts->prev_f2id = f2id;
+evt_out:
+	return IRQ_HANDLED;
+}
+
+static int cy8ctma140_init(struct cy8ctma140 *ts)
+{
+	u8 addr[1];
+	u8 buf[5];
+	int ret;
+
+	addr[0] = CY8CTMA140_GET_FW_INFO;
+	ret = i2c_master_send(ts->client, addr, 1);
+	if (ret < 0) {
+		dev_err(ts->dev, "error sending FW info message\n");
+		return ret;
+	}
+	ret = i2c_master_recv(ts->client, buf, 5);
+	if (ret < 0) {
+		dev_err(ts->dev, "error recieveing FW info message\n");
+		return ret;
+	}
+	if (ret != 5) {
+		dev_err(ts->dev, "got only %d bytes\n", ret);
+		return -EIO;
+	}
+
+	dev_info(ts->dev, "vendor %c%c, HW ID %.2d, FW ver %.4d\n",
+		 buf[0], buf[1], buf[3], buf[4]);
+	return 0;
+}
+
+static int cy8ctma140_power_up(struct cy8ctma140 *ts)
+{
+	int error;
+
+	error = regulator_bulk_enable(ARRAY_SIZE(ts->regulators),
+				      ts->regulators);
+	if (error) {
+		dev_err(ts->dev, "failed to enable regulators\n");
+		return error;
+	}
+
+	msleep(250);
+
+	return 0;
+}
+
+static void cy8ctma140_power_down(struct cy8ctma140 *ts)
+{
+	regulator_bulk_disable(ARRAY_SIZE(ts->regulators),
+			       ts->regulators);
+}
+
+/* Called from the registered devm action */
+static void cy8ctma140_power_off_action(void *d)
+{
+	struct cy8ctma140 *ts = d;
+
+	cy8ctma140_power_down(ts);
+}
+
+static int cy8ctma140_probe(struct i2c_client *client,
+			    const struct i2c_device_id *id)
+{
+	struct cy8ctma140 *ts;
+	struct input_dev *input;
+	struct device *dev = &client->dev;
+	int ret;
+
+	ts = devm_kzalloc(dev, sizeof(*ts), GFP_KERNEL);
+	if (!ts)
+		return -ENOMEM;
+
+	input = devm_input_allocate_device(dev);
+	if (!input)
+		return -ENOMEM;
+
+	ts->dev = dev;
+	ts->client = client;
+	ts->input = input;
+
+	input_set_capability(input, EV_ABS, ABS_MT_POSITION_X);
+	input_set_capability(input, EV_ABS, ABS_MT_POSITION_Y);
+	/* One byte for width 0..255 so this is the limit */
+	input_set_abs_params(input, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0);
+	/*
+	 * This sets up event max/min capabilities and fuzz.
+	 * Some DT properties are compulsory so we do not need
+	 * to provide defaults for X/Y max or pressure max.
+	 *
+	 * We just initialize a very simple MT touchscreen here,
+	 * some devices use the capability of this touchscreen to
+	 * provide touchkeys, and in that case this needs to be
+	 * extended to handle touchkey input.
+	 *
+	 * The firmware takes care of finger tracking and dropping
+	 * invalid ranges.
+	 */
+	touchscreen_parse_properties(input, true, &ts->props);
+	input_abs_set_fuzz(input, ABS_MT_POSITION_X, 0);
+	input_abs_set_fuzz(input, ABS_MT_POSITION_Y, 0);
+
+	ret = input_mt_init_slots(input, CY8CTMA140_MAX_FINGERS,
+				  INPUT_MT_DIRECT);
+	if (ret)
+		return ret;
+
+	input->name = CY8CTMA140_NAME;
+	input->id.bustype = BUS_I2C;
+	input_set_drvdata(input, ts);
+
+	/*
+	 * VCPIN is the analog voltage supply
+	 * VDD is the digital voltage supply
+	 * since the voltage range of VDD overlaps that of VCPIN,
+	 * many designs to just supply both with a single voltage
+	 * source of ~3.3 V.
+	 */
+	ts->regulators[0].supply = "vcpin";
+	ts->regulators[1].supply = "vdd";
+	ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(ts->regulators),
+				      ts->regulators);
+	if (ret) {
+		if (ret != -EPROBE_DEFER)
+			dev_err(dev, "Failed to get regulators %d\n",
+				ret);
+		return ret;
+	}
+
+	ret = cy8ctma140_power_up(ts);
+	if (ret)
+		return ret;
+	ret = devm_add_action_or_reset(dev, cy8ctma140_power_off_action, ts);
+	if (ret) {
+		dev_err(dev, "failed to install power off handler\n");
+		return ret;
+	}
+
+	ret = devm_request_threaded_irq(dev, client->irq, NULL,
+					cy8ctma140_irq_thread,
+					IRQF_ONESHOT,
+					CY8CTMA140_NAME, ts);
+	if (ret) {
+		dev_err(dev, "irq %d busy? error %d\n", client->irq, ret);
+		goto err_reg_dis;
+	}
+
+	ret = cy8ctma140_init(ts);
+	if (ret)
+		return ret;
+
+	ret = input_register_device(input);
+	if (ret)
+		goto err_reg_dis;
+
+	i2c_set_clientdata(client, ts);
+
+	return 0;
+
+err_reg_dis:
+	cy8ctma140_power_down(ts);
+	return ret;
+}
+
+static int __maybe_unused cy8ctma140_suspend(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct cy8ctma140 *ts = i2c_get_clientdata(client);
+
+	if (!device_may_wakeup(&client->dev))
+		cy8ctma140_power_down(ts);
+	input_mt_slot(ts->input, 0);
+	input_mt_report_slot_state(ts->input, MT_TOOL_FINGER, false);
+	input_mt_slot(ts->input, 1);
+	input_mt_report_slot_state(ts->input, MT_TOOL_FINGER, false);
+	input_mt_report_pointer_emulation(ts->input, true);
+	input_sync(ts->input);
+
+	return 0;
+}
+
+static int __maybe_unused cy8ctma140_resume(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct cy8ctma140 *ts = i2c_get_clientdata(client);
+	int ret;
+
+	if (!device_may_wakeup(&client->dev)) {
+		ret = cy8ctma140_power_up(ts);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(cy8ctma140_pm, cy8ctma140_suspend, cy8ctma140_resume);
+
+static const struct i2c_device_id cy8ctma140_idtable[] = {
+	{ CY8CTMA140_NAME, 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, cy8ctma140_idtable);
+
+static const struct of_device_id cy8ctma140_of_match[] = {
+	{
+		.compatible = "cypress,cy8ctma140",
+	},
+};
+MODULE_DEVICE_TABLE(of, cy8ctma140_of_match);
+
+static struct i2c_driver cy8ctma140_driver = {
+	.driver		= {
+		.name	= CY8CTMA140_NAME,
+		.pm	= &cy8ctma140_pm,
+		.of_match_table = cy8ctma140_of_match,
+	},
+	.id_table	= cy8ctma140_idtable,
+	.probe		= cy8ctma140_probe,
+};
+module_i2c_driver(cy8ctma140_driver);
+
+MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>");
+MODULE_DESCRIPTION("CY8CTMA140 TouchScreen Driver");
+MODULE_LICENSE("GPL v2");