[v4] ARM: dts: motorola-mapphone-common: Add dts configureation for the android buttons beneath the screen

diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig
index 362e8a01980c..3d487b8e7d8b 100644
--- a/drivers/input/misc/Kconfig
+++ b/drivers/input/misc/Kconfig
@@ -318,6 +318,14 @@  config INPUT_CPCAP_PWRBUTTON
 	  To compile this driver as a module, choose M here. The module will
 	  be called cpcap-pwrbutton.
 
+config INPUT_TOUCHSCREEN_BUTTONS
+	tristate "Touchscreen Buttons"
+	help
+	  Say Y here if you want to enable buttons on touchscreen devices.
+
+	  To compile this driver as a module, choose M here. The module will
+	  be called touchscreen-buttons.
+
 config INPUT_WISTRON_BTNS
 	tristate "x86 Wistron laptop button interface"
 	depends on X86_32
diff --git a/drivers/input/misc/Makefile b/drivers/input/misc/Makefile
index a48e5f2d859d..18032a1b2a9c 100644
--- a/drivers/input/misc/Makefile
+++ b/drivers/input/misc/Makefile
@@ -84,4 +84,5 @@  obj-$(CONFIG_INPUT_WM831X_ON)		+= wm831x-on.o
 obj-$(CONFIG_INPUT_XEN_KBDDEV_FRONTEND)	+= xen-kbdfront.o
 obj-$(CONFIG_INPUT_YEALINK)		+= yealink.o
 obj-$(CONFIG_INPUT_IDEAPAD_SLIDEBAR)	+= ideapad_slidebar.o
+obj-$(CONFIG_INPUT_TOUCHSCREEN_BUTTONS)	+= touchscreen-buttons.o
 
diff --git a/drivers/input/misc/touchscreen-buttons.c b/drivers/input/misc/touchscreen-buttons.c
new file mode 100644
index 000000000000..8b40dbb874c3
--- /dev/null
+++ b/drivers/input/misc/touchscreen-buttons.c
@@ -0,0 +1,592 @@ 
+// SPDX-License-Identifier: GPL-2.0-or-later
+/**
+ * Touchscreen Virutal Button Input Driver
+ *
+ * Copyright (C) 2020 Carl Klemm <carl@uvos.xyz>
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file "COPYING" in the main directory of this
+ * archive for more details.
+ *
+ * This program 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.
+ */
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/platform_device.h>
+#include <linux/errno.h>
+#include <linux/input.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/kernel.h>
+#include <linux/limits.h>
+#include <linux/input/mt.h>
+#include <linux/device/bus.h>
+#include <linux/string.h>
+#include <linux/workqueue.h>
+
+#define EVENT_QUEUE_SIZE 32
+
+struct touchscreen_button {
+	u32 x;
+	u32 y;
+	u32 width;
+	u32 height;
+	u32 keycode;
+	u8 depressed;
+};
+
+struct touchscreen_button_map {
+	struct touchscreen_button *buttons;
+	u32 count;
+	struct device_node *ts_node;
+};
+
+struct event {
+	unsigned int type;
+	unsigned int code;
+	int value;
+};
+
+struct event_queue {
+	struct event events[EVENT_QUEUE_SIZE];
+	unsigned int lastindex;
+};
+
+struct touchscreen_buttons {
+	struct device *dev;
+	struct input_dev *buttons_idev;
+	struct input_dev *filtered_ts_idev;
+	struct touchscreen_button_map *map;
+	struct input_handler *handler;
+	struct input_handle *ts_handle;
+	struct event_queue queue;
+	struct workqueue_struct *workqueue;
+	struct work_struct open_task;
+	struct work_struct close_task;
+	struct work_struct merge_task;
+	struct mutex mutex;
+};
+
+static const struct input_device_id touchscreen_buttons_ids[] = {
+	{
+	 .flags = INPUT_DEVICE_ID_MATCH_EVBIT,
+	 .evbit = {BIT_MASK(EV_ABS)},
+	 },
+	{
+	 .flags = INPUT_DEVICE_ID_MATCH_EVBIT,
+	 .evbit = {BIT_MASK(EV_KEY)},
+	 },
+	{
+	 .flags = INPUT_DEVICE_ID_MATCH_EVBIT,
+	 .evbit = {BIT_MASK(EV_SYN)},
+	 },
+	{},
+};
+
+static int touchscreen_buttons_process_syn(const struct event_queue *queue,
+					   const struct touchscreen_button_map
+					   *map, struct input_dev *idev)
+{
+	u32 i;
+	int x, y, ret, pressed;
+
+	x = INT_MIN;
+	y = INT_MIN;
+	pressed = -1;
+	ret = 0;
+
+	for (i = 0; i < queue->lastindex; ++i) {
+		const struct event *ev;
+
+		ev = &queue->events[i];
+		if (ev->type == EV_ABS && ev->code == ABS_X)
+			x = ev->value;
+		else if (ev->type == EV_ABS && ev->code == ABS_Y)
+			y = ev->value;
+		else if (ev->type == EV_KEY && ev->code == BTN_TOUCH)
+			pressed = ev->value;
+	}
+
+	for (i = 0; i < map->count; ++i) {
+		struct touchscreen_button *button = &map->buttons[i];
+
+		if (pressed == 1 &&
+		    button->x <= x &&
+		    button->y <= y &&
+		    button->width + button->x >= x &&
+		    button->height + button->y >= y && button->depressed == 0) {
+			input_report_key(idev, button->keycode, 1);
+			button->depressed = 1;
+			ret = 1;
+		} else if (button->depressed == 1) {
+			if (pressed == 0) {
+				input_report_key(idev, button->keycode, 0);
+				button->depressed = 0;
+			}
+			ret = 2;
+		}
+	}
+
+	if (ret != 0) {
+		input_event(idev, EV_SYN, SYN_REPORT, 0);
+	} else if (ret == 0) {
+		bool buttonpressed = false;
+
+		for (i = 0; i < map->count; ++i)
+			buttonpressed = buttonpressed
+			    || map->buttons[i].depressed;
+		if (buttonpressed)
+			ret = 3;
+	}
+
+	return ret;
+}
+
+static void touchscreen_buttons_resend_events(const struct event_queue *queue,
+					      struct input_dev *idev)
+{
+	u32 i;
+
+	for (i = 0; i < queue->lastindex; ++i)
+		input_event(idev, queue->events[i].type, queue->events[i].code,
+			    queue->events[i].value);
+	input_event(idev, EV_SYN, SYN_REPORT, 0);
+}
+
+static void touchscreen_buttons_copy_mt_slots(struct input_dev *target,
+					      struct input_dev *source)
+{
+	if (source->mt && target->mt
+	    && source->mt->num_slots == target->mt->num_slots) {
+		memcpy(target->mt->slots, source->mt->slots,
+		       sizeof(struct input_mt_slot) * source->mt->num_slots);
+	}
+}
+
+static void touchscreen_buttons_input_event(struct input_handle *handle,
+					    unsigned int type,
+					    unsigned int code, int value)
+{
+	struct touchscreen_buttons *buttons;
+
+	buttons = handle->private;
+
+	if (type == EV_SYN && code == SYN_REPORT) {
+		if (touchscreen_buttons_process_syn(&buttons->queue,
+						    buttons->map,
+						    buttons->buttons_idev) == 0)
+			touchscreen_buttons_resend_events(&buttons->queue,
+							  buttons->filtered_ts_idev);
+		buttons->queue.lastindex = 0;
+	} else if (buttons->queue.lastindex < EVENT_QUEUE_SIZE) {
+		buttons->queue.events[buttons->queue.lastindex].type = type;
+		buttons->queue.events[buttons->queue.lastindex].code = code;
+		buttons->queue.events[buttons->queue.lastindex].value = value;
+		++buttons->queue.lastindex;
+	} else {
+		dev_warn(buttons->dev,
+			 "event_qeue overrun, will not capture events until next SYN_REPORT\n");
+	}
+}
+
+static void touchscreen_buttons_merge_capabilitys(struct input_dev *target,
+						  struct input_dev *source)
+{
+	unsigned int i;
+
+	mutex_lock(&target->mutex);
+	mutex_lock(&source->mutex);
+	for (i = 0; i < BITS_TO_LONGS(INPUT_PROP_CNT); ++i)
+		target->propbit[i] = target->propbit[i] | source->propbit[i];
+	for (i = 0; i < BITS_TO_LONGS(EV_CNT); ++i)
+		target->evbit[i] = target->evbit[i] | source->evbit[i];
+	for (i = 0; i < BITS_TO_LONGS(KEY_CNT); ++i)
+		target->keybit[i] = target->keybit[i] | source->keybit[i];
+	for (i = 0; i < BITS_TO_LONGS(REL_CNT); ++i)
+		target->relbit[i] = target->relbit[i] | source->relbit[i];
+	for (i = 0; i < BITS_TO_LONGS(ABS_CNT); ++i)
+		target->absbit[i] = target->absbit[i] | source->absbit[i];
+	for (i = 0; i < BITS_TO_LONGS(MSC_CNT); ++i)
+		target->mscbit[i] = target->mscbit[i] | source->mscbit[i];
+	for (i = 0; i < BITS_TO_LONGS(LED_CNT); ++i)
+		target->ledbit[i] = target->ledbit[i] | source->ledbit[i];
+	for (i = 0; i < BITS_TO_LONGS(SND_CNT); ++i)
+		target->sndbit[i] = target->sndbit[i] | source->sndbit[i];
+	for (i = 0; i < BITS_TO_LONGS(FF_CNT); ++i)
+		target->ffbit[i] = target->ffbit[i] | source->ffbit[i];
+	for (i = 0; i < BITS_TO_LONGS(SW_CNT); ++i)
+		target->swbit[i] = target->swbit[i] | source->swbit[i];
+
+	if (*source->evbit & (1 << EV_ABS)) {
+		input_alloc_absinfo(target);
+		for (i = 0; i < ABS_CNT; ++i)
+			target->absinfo[i] = source->absinfo[i];
+		if (source->mt) {
+			input_mt_init_slots(target, source->mt->num_slots,
+					    source->mt->flags);
+			touchscreen_buttons_copy_mt_slots(target, source);
+		}
+	}
+	mutex_unlock(&source->mutex);
+	mutex_unlock(&target->mutex);
+}
+
+static void merge_task_handler(struct work_struct *work)
+{
+	struct touchscreen_buttons *buttons =
+	    container_of(work, struct touchscreen_buttons, merge_task);
+
+	mutex_lock(&buttons->mutex);
+	if (buttons->ts_handle && buttons->ts_handle->dev)
+		touchscreen_buttons_merge_capabilitys(buttons->filtered_ts_idev,
+						      buttons->ts_handle->dev);
+	mutex_unlock(&buttons->mutex);
+}
+
+static void close_task_handler(struct work_struct *work)
+{
+	struct touchscreen_buttons *buttons =
+	    container_of(work, struct touchscreen_buttons, close_task);
+
+	mutex_lock(&buttons->mutex);
+	if (buttons && buttons->ts_handle && buttons->ts_handle->open != 0)
+		input_close_device(buttons->ts_handle);
+	mutex_unlock(&buttons->mutex);
+}
+
+static void open_task_handler(struct work_struct *work)
+{
+	struct touchscreen_buttons *buttons =
+	    container_of(work, struct touchscreen_buttons, open_task);
+	int error;
+
+	mutex_lock(&buttons->mutex);
+	if (buttons && buttons->ts_handle) {
+		error = input_open_device(buttons->ts_handle);
+		if (error) {
+			dev_err(buttons->dev,
+				"Failed to open input device, error %d\n",
+				error);
+			input_unregister_handle(buttons->ts_handle);
+			kfree(buttons->ts_handle);
+			buttons->ts_handle = NULL;
+		}
+	}
+	mutex_unlock(&buttons->mutex);
+}
+
+static int touchscreen_buttons_input_connect(struct input_handler *handler,
+					     struct input_dev *dev,
+					     const struct input_device_id *id)
+{
+	struct touchscreen_buttons *buttons;
+
+	buttons = handler->private;
+
+	mutex_lock(&buttons->mutex);
+
+	if ((!buttons->ts_handle
+	     && device_match_of_node(&dev->dev, buttons->map->ts_node))
+	    || (dev->dev.parent
+		&& device_match_of_node(dev->dev.parent,
+					buttons->map->ts_node))) {
+		int error;
+
+		dev_info(buttons->dev, "Binding to device: %s\n",
+			 dev_name(&dev->dev));
+
+		buttons->ts_handle =
+		    kzalloc(sizeof(*buttons->ts_handle), GFP_KERNEL);
+		if (!buttons->ts_handle) {
+			mutex_unlock(&buttons->mutex);
+			return -ENOMEM;
+		}
+
+		buttons->ts_handle->dev = dev;
+		buttons->ts_handle->handler = handler;
+		buttons->ts_handle->name = "touchscreen-buttons";
+		buttons->ts_handle->private = handler->private;
+		buttons->queue.lastindex = 0;
+
+		error = input_register_handle(buttons->ts_handle);
+		if (error) {
+			dev_err(buttons->dev,
+				"Failed to register input handler, error %d\n",
+				error);
+			kfree(buttons->ts_handle);
+			buttons->ts_handle = NULL;
+			mutex_unlock(&buttons->mutex);
+			return error;
+		}
+
+		queue_work(buttons->workqueue, &buttons->merge_task);
+
+		if (buttons->filtered_ts_idev->users > 0
+		    && buttons->ts_handle->open == 0)
+			queue_work(buttons->workqueue, &buttons->open_task);
+	}
+
+	mutex_unlock(&buttons->mutex);
+	return 0;
+}
+
+static void touchscreen_buttons_input_disconnect(struct input_handle *handle)
+{
+	struct touchscreen_buttons *buttons;
+
+	buttons = handle->private;
+
+	mutex_lock(&buttons->mutex);
+	if (handle == buttons->ts_handle) {
+		input_close_device(handle);
+		input_unregister_handle(handle);
+		kfree(handle);
+		buttons->ts_handle = NULL;
+		dev_info(buttons->dev,
+			 "Touchscreen device disconnected buttons disabled\n");
+	} else {
+		dev_err(buttons->dev,
+			"Unknown device disconnected, %p should be %p", handle,
+			buttons->ts_handle);
+	}
+	mutex_unlock(&buttons->mutex);
+}
+
+static struct touchscreen_button_map
+*touchscreen_buttons_get_devtree_pdata(struct device *dev)
+{
+	struct touchscreen_button_map *map;
+	struct fwnode_handle *child_node;
+	struct device_node *node;
+	int i;
+
+	map = kzalloc(sizeof(*map), GFP_KERNEL);
+	if (!map)
+		return ERR_PTR(-ENOMEM);
+
+	map->count = device_get_child_node_count(dev);
+	if (map->count == 0) {
+		kfree(map);
+		return ERR_PTR(-ENODEV);
+	}
+
+	map->buttons = kcalloc(map->count, sizeof(*map->buttons), GFP_KERNEL);
+	if (!map->buttons)
+		return ERR_PTR(-ENOMEM);
+
+	node = dev->of_node;
+	map->ts_node = of_parse_phandle(node, "touchscreen_phandle", 0);
+	if (!map->ts_node) {
+		dev_err(dev, "touchscreen_phandle node missing\n");
+		return ERR_PTR(-ENODEV);
+	}
+
+	dev_info(dev, "Device_node name: %s\n", map->ts_node->name);
+
+	i = 0;
+	device_for_each_child_node(dev, child_node) {
+		struct touchscreen_button *button;
+
+		button = &map->buttons[i];
+
+		fwnode_property_read_u32(child_node, "x-position", &button->x);
+		fwnode_property_read_u32(child_node, "y-position", &button->y);
+		fwnode_property_read_u32(child_node, "x-size", &button->width);
+		fwnode_property_read_u32(child_node, "y-size", &button->height);
+		fwnode_property_read_u32(child_node, "keycode",
+					 &button->keycode);
+		dev_info(dev,
+			 "Adding button at x=%u y=%u size %u x %u keycode=%u\n",
+			 button->x, button->y, button->width, button->height,
+			 button->keycode);
+		++i;
+	}
+	return map;
+}
+
+static int touchscreen_buttons_idev_opened(struct input_dev *idev)
+{
+	struct touchscreen_buttons *buttons;
+
+	buttons = dev_get_drvdata(idev->dev.parent);
+
+	mutex_lock(&buttons->mutex);
+	if (buttons && buttons->ts_handle) {
+		if (buttons->ts_handle->open == 0) {
+			queue_work(buttons->workqueue, &buttons->open_task);
+			dev_dbg(idev->dev.parent, "idev opened\n");
+		} else {
+			dev_info(idev->dev.parent, "idev allready opened\n");
+		}
+	} else {
+		dev_warn(idev->dev.parent,
+			 "Input device opend but touchscreen not opened. %p %p\n",
+			 buttons, buttons->ts_handle);
+	}
+	mutex_unlock(&buttons->mutex);
+	return 0;
+}
+
+static void touchscreen_buttons_idev_closed(struct input_dev *idev)
+{
+	struct touchscreen_buttons *buttons;
+
+	buttons = dev_get_drvdata(idev->dev.parent);
+
+	mutex_lock(&buttons->mutex);
+	if (buttons && buttons->ts_handle && buttons->ts_handle->open != 0) {
+		queue_work(buttons->workqueue, &buttons->close_task);
+		dev_dbg(idev->dev.parent, "idev closed\n");
+	}
+	mutex_unlock(&buttons->mutex);
+}
+
+static int touchscreen_buttons_probe(struct platform_device *pdev)
+{
+	struct touchscreen_buttons *buttons;
+	int error, i;
+
+	buttons = devm_kzalloc(&pdev->dev, sizeof(*buttons), GFP_KERNEL);
+	if (!buttons)
+		return -ENOMEM;
+
+	dev_set_drvdata(&pdev->dev, buttons);
+
+	buttons->workqueue =
+	    create_singlethread_workqueue("touchscreen-buttons-workqueue");
+	INIT_WORK(&buttons->merge_task, merge_task_handler);
+	INIT_WORK(&buttons->open_task, open_task_handler);
+	INIT_WORK(&buttons->close_task, close_task_handler);
+
+	mutex_init(&buttons->mutex);
+
+	buttons->queue.lastindex = 0;
+	buttons->dev = &pdev->dev;
+
+	buttons->map = touchscreen_buttons_get_devtree_pdata(&pdev->dev);
+	if (IS_ERR(buttons->map))
+		return PTR_ERR(buttons->map);
+
+	/*filtered touchscreen device */
+	buttons->filtered_ts_idev = input_allocate_device();
+	if (!buttons->filtered_ts_idev)
+		return -ENOMEM;
+	buttons->filtered_ts_idev->name = "Filtered Touchscreen";
+	buttons->filtered_ts_idev->phys = "touchscreen-buttons/input1";
+	buttons->filtered_ts_idev->dev.parent = buttons->dev;
+	buttons->filtered_ts_idev->open = touchscreen_buttons_idev_opened;
+	buttons->filtered_ts_idev->close = touchscreen_buttons_idev_closed;
+
+	/*buttons input device */
+	buttons->buttons_idev = input_allocate_device();
+	if (!buttons->buttons_idev)
+		return -ENOMEM;
+	buttons->buttons_idev->name = "Touchscreen Buttons";
+	buttons->buttons_idev->phys = "touchscreen-buttons/input0";
+	buttons->buttons_idev->dev.parent = buttons->dev;
+	for (i = 0; i < buttons->map->count; ++i)
+		input_set_capability(buttons->buttons_idev, EV_KEY,
+				     buttons->map->buttons[i].keycode);
+
+	/*handler for touchscreen input device */
+	buttons->handler = kzalloc(sizeof(*buttons->handler), GFP_KERNEL);
+
+	buttons->handler->event = touchscreen_buttons_input_event;
+	buttons->handler->connect = touchscreen_buttons_input_connect;
+	buttons->handler->disconnect = touchscreen_buttons_input_disconnect;
+	buttons->handler->name = "touchscreen-buttons";
+	buttons->handler->id_table = touchscreen_buttons_ids;
+	buttons->handler->private = buttons;
+
+	error = input_register_handler(buttons->handler);
+	if (error) {
+		dev_err(&pdev->dev, "Input handler register failed: %d\n",
+			error);
+		return error;
+	}
+
+	error = input_register_device(buttons->buttons_idev);
+	if (error) {
+		dev_err(&pdev->dev, "Input device register failed: %d\n",
+			error);
+		return error;
+	}
+
+	error = input_register_device(buttons->filtered_ts_idev);
+	if (error) {
+		dev_err(&pdev->dev, "Input device register failed: %d\n",
+			error);
+		return error;
+	}
+
+	return 0;
+}
+
+static int touchscreen_buttons_remove(struct platform_device *pdev)
+{
+	struct touchscreen_buttons *buttons;
+	struct input_handle *ts_handle;
+
+	buttons = dev_get_drvdata(&pdev->dev);
+
+	mutex_lock(&buttons->mutex);
+
+	ts_handle = buttons->ts_handle;
+
+	input_unregister_handler(buttons->handler);
+	if (buttons->ts_handle) {
+		if (buttons->ts_handle->open != 0)
+			input_close_device(buttons->ts_handle);
+		input_unregister_handle(buttons->ts_handle);
+		buttons->ts_handle = NULL;
+	}
+
+	mutex_unlock(&buttons->mutex);
+
+	flush_workqueue(buttons->workqueue);
+	destroy_workqueue(buttons->workqueue);
+
+	input_unregister_device(buttons->buttons_idev);
+	input_unregister_device(buttons->filtered_ts_idev);
+
+	kfree(ts_handle);
+
+	if (buttons->map) {
+		kfree(buttons->map->buttons);
+		kfree(buttons->map);
+	}
+	kfree(buttons->handler);
+
+	return 0;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id touchscreen_buttons_dt_match_table[] = {
+	{.compatible = "touchscreen-buttons"},
+	{},
+};
+
+MODULE_DEVICE_TABLE(of, touchscreen_buttons_dt_match_table);
+#endif
+
+static struct platform_driver touchscreen_buttons_driver = {
+	.probe = touchscreen_buttons_probe,
+	.remove = touchscreen_buttons_remove,
+	.driver = {
+		   .name = "touchscreen-buttons",
+		   .of_match_table =
+		   of_match_ptr(touchscreen_buttons_dt_match_table),
+		   },
+};
+
+module_platform_driver(touchscreen_buttons_driver);
+
+MODULE_ALIAS("platform:touchscreen-buttons");
+MODULE_DESCRIPTION("touchscreen-buttons");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Carl Klemm <carl@uvos.xyz>");