v4.19.13 snapshot.
diff --git a/drivers/input/mouse/gpio_mouse.c b/drivers/input/mouse/gpio_mouse.c
new file mode 100644
index 0000000..a26d8be
--- /dev/null
+++ b/drivers/input/mouse/gpio_mouse.c
@@ -0,0 +1,178 @@
+/*
+ * Driver for simulating a mouse on GPIO lines.
+ *
+ * Copyright (C) 2007 Atmel Corporation
+ * Copyright (C) 2017 Linus Walleij <linus.walleij@linaro.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/input-polldev.h>
+#include <linux/gpio/consumer.h>
+#include <linux/property.h>
+#include <linux/of.h>
+
+/**
+ * struct gpio_mouse
+ * @scan_ms: the scan interval in milliseconds.
+ * @up: GPIO line for up value.
+ * @down: GPIO line for down value.
+ * @left: GPIO line for left value.
+ * @right: GPIO line for right value.
+ * @bleft: GPIO line for left button.
+ * @bmiddle: GPIO line for middle button.
+ * @bright: GPIO line for right button.
+ *
+ * This struct must be added to the platform_device in the board code.
+ * It is used by the gpio_mouse driver to setup GPIO lines and to
+ * calculate mouse movement.
+ */
+struct gpio_mouse {
+ u32 scan_ms;
+ struct gpio_desc *up;
+ struct gpio_desc *down;
+ struct gpio_desc *left;
+ struct gpio_desc *right;
+ struct gpio_desc *bleft;
+ struct gpio_desc *bmiddle;
+ struct gpio_desc *bright;
+};
+
+/*
+ * Timer function which is run every scan_ms ms when the device is opened.
+ * The dev input variable is set to the the input_dev pointer.
+ */
+static void gpio_mouse_scan(struct input_polled_dev *dev)
+{
+ struct gpio_mouse *gpio = dev->private;
+ struct input_dev *input = dev->input;
+ int x, y;
+
+ if (gpio->bleft)
+ input_report_key(input, BTN_LEFT,
+ gpiod_get_value(gpio->bleft));
+ if (gpio->bmiddle)
+ input_report_key(input, BTN_MIDDLE,
+ gpiod_get_value(gpio->bmiddle));
+ if (gpio->bright)
+ input_report_key(input, BTN_RIGHT,
+ gpiod_get_value(gpio->bright));
+
+ x = gpiod_get_value(gpio->right) - gpiod_get_value(gpio->left);
+ y = gpiod_get_value(gpio->down) - gpiod_get_value(gpio->up);
+
+ input_report_rel(input, REL_X, x);
+ input_report_rel(input, REL_Y, y);
+ input_sync(input);
+}
+
+static int gpio_mouse_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct gpio_mouse *gmouse;
+ struct input_polled_dev *input_poll;
+ struct input_dev *input;
+ int ret;
+
+ gmouse = devm_kzalloc(dev, sizeof(*gmouse), GFP_KERNEL);
+ if (!gmouse)
+ return -ENOMEM;
+
+ /* Assign some default scanning time */
+ ret = device_property_read_u32(dev, "scan-interval-ms",
+ &gmouse->scan_ms);
+ if (ret || gmouse->scan_ms == 0) {
+ dev_warn(dev, "invalid scan time, set to 50 ms\n");
+ gmouse->scan_ms = 50;
+ }
+
+ gmouse->up = devm_gpiod_get(dev, "up", GPIOD_IN);
+ if (IS_ERR(gmouse->up))
+ return PTR_ERR(gmouse->up);
+ gmouse->down = devm_gpiod_get(dev, "down", GPIOD_IN);
+ if (IS_ERR(gmouse->down))
+ return PTR_ERR(gmouse->down);
+ gmouse->left = devm_gpiod_get(dev, "left", GPIOD_IN);
+ if (IS_ERR(gmouse->left))
+ return PTR_ERR(gmouse->left);
+ gmouse->right = devm_gpiod_get(dev, "right", GPIOD_IN);
+ if (IS_ERR(gmouse->right))
+ return PTR_ERR(gmouse->right);
+
+ gmouse->bleft = devm_gpiod_get_optional(dev, "button-left", GPIOD_IN);
+ if (IS_ERR(gmouse->bleft))
+ return PTR_ERR(gmouse->bleft);
+ gmouse->bmiddle = devm_gpiod_get_optional(dev, "button-middle",
+ GPIOD_IN);
+ if (IS_ERR(gmouse->bmiddle))
+ return PTR_ERR(gmouse->bmiddle);
+ gmouse->bright = devm_gpiod_get_optional(dev, "button-right",
+ GPIOD_IN);
+ if (IS_ERR(gmouse->bright))
+ return PTR_ERR(gmouse->bright);
+
+ input_poll = devm_input_allocate_polled_device(dev);
+ if (!input_poll) {
+ dev_err(dev, "not enough memory for input device\n");
+ return -ENOMEM;
+ }
+
+ platform_set_drvdata(pdev, input_poll);
+
+ /* set input-polldev handlers */
+ input_poll->private = gmouse;
+ input_poll->poll = gpio_mouse_scan;
+ input_poll->poll_interval = gmouse->scan_ms;
+
+ input = input_poll->input;
+ input->name = pdev->name;
+ input->id.bustype = BUS_HOST;
+ input->dev.parent = &pdev->dev;
+
+ input_set_capability(input, EV_REL, REL_X);
+ input_set_capability(input, EV_REL, REL_Y);
+ if (gmouse->bleft)
+ input_set_capability(input, EV_KEY, BTN_LEFT);
+ if (gmouse->bmiddle)
+ input_set_capability(input, EV_KEY, BTN_MIDDLE);
+ if (gmouse->bright)
+ input_set_capability(input, EV_KEY, BTN_RIGHT);
+
+ ret = input_register_polled_device(input_poll);
+ if (ret) {
+ dev_err(dev, "could not register input device\n");
+ return ret;
+ }
+
+ dev_dbg(dev, "%d ms scan time, buttons: %s%s%s\n",
+ gmouse->scan_ms,
+ gmouse->bleft ? "" : "left ",
+ gmouse->bmiddle ? "" : "middle ",
+ gmouse->bright ? "" : "right");
+
+ return 0;
+}
+
+static const struct of_device_id gpio_mouse_of_match[] = {
+ { .compatible = "gpio-mouse", },
+ { },
+};
+MODULE_DEVICE_TABLE(of, gpio_mouse_of_match);
+
+static struct platform_driver gpio_mouse_device_driver = {
+ .probe = gpio_mouse_probe,
+ .driver = {
+ .name = "gpio_mouse",
+ .of_match_table = gpio_mouse_of_match,
+ }
+};
+module_platform_driver(gpio_mouse_device_driver);
+
+MODULE_AUTHOR("Hans-Christian Egtvedt <egtvedt@samfundet.no>");
+MODULE_DESCRIPTION("GPIO mouse driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:gpio_mouse"); /* work with hotplug and coldplug */