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-rw-r--r--drivers/input/joystick/sensehat-joystick.c135
1 files changed, 135 insertions, 0 deletions
diff --git a/drivers/input/joystick/sensehat-joystick.c b/drivers/input/joystick/sensehat-joystick.c
new file mode 100644
index 0000000000..a84df39d3b
--- /dev/null
+++ b/drivers/input/joystick/sensehat-joystick.c
@@ -0,0 +1,135 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Raspberry Pi Sense HAT joystick driver
+ * http://raspberrypi.org
+ *
+ * Copyright (C) 2015 Raspberry Pi
+ * Copyright (C) 2021 Charles Mirabile, Mwesigwa Guma, Joel Savitz
+ *
+ * Original Author: Serge Schneider
+ * Revised for upstream Linux by: Charles Mirabile, Mwesigwa Guma, Joel Savitz
+ */
+
+#include <linux/module.h>
+#include <linux/input.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/property.h>
+
+#define JOYSTICK_SMB_REG 0xf2
+
+struct sensehat_joystick {
+ struct platform_device *pdev;
+ struct input_dev *keys_dev;
+ unsigned long prev_states;
+ struct regmap *regmap;
+};
+
+static const unsigned int keymap[] = {
+ BTN_DPAD_DOWN, BTN_DPAD_RIGHT, BTN_DPAD_UP, BTN_SELECT, BTN_DPAD_LEFT,
+};
+
+static irqreturn_t sensehat_joystick_report(int irq, void *cookie)
+{
+ struct sensehat_joystick *sensehat_joystick = cookie;
+ unsigned long curr_states, changes;
+ unsigned int keys;
+ int error;
+ int i;
+
+ error = regmap_read(sensehat_joystick->regmap, JOYSTICK_SMB_REG, &keys);
+ if (error < 0) {
+ dev_err(&sensehat_joystick->pdev->dev,
+ "Failed to read joystick state: %d", error);
+ return IRQ_NONE;
+ }
+ curr_states = keys;
+ bitmap_xor(&changes, &curr_states, &sensehat_joystick->prev_states,
+ ARRAY_SIZE(keymap));
+
+ for_each_set_bit(i, &changes, ARRAY_SIZE(keymap))
+ input_report_key(sensehat_joystick->keys_dev, keymap[i],
+ curr_states & BIT(i));
+
+ input_sync(sensehat_joystick->keys_dev);
+ sensehat_joystick->prev_states = keys;
+ return IRQ_HANDLED;
+}
+
+static int sensehat_joystick_probe(struct platform_device *pdev)
+{
+ struct sensehat_joystick *sensehat_joystick;
+ int error, i, irq;
+
+ sensehat_joystick = devm_kzalloc(&pdev->dev, sizeof(*sensehat_joystick),
+ GFP_KERNEL);
+ if (!sensehat_joystick)
+ return -ENOMEM;
+
+ sensehat_joystick->pdev = pdev;
+
+ sensehat_joystick->regmap = dev_get_regmap(pdev->dev.parent, NULL);
+ if (!sensehat_joystick->regmap) {
+ dev_err(&pdev->dev, "unable to get sensehat regmap");
+ return -ENODEV;
+ }
+
+ sensehat_joystick->keys_dev = devm_input_allocate_device(&pdev->dev);
+ if (!sensehat_joystick->keys_dev) {
+ dev_err(&pdev->dev, "Could not allocate input device");
+ return -ENOMEM;
+ }
+
+ sensehat_joystick->keys_dev->name = "Raspberry Pi Sense HAT Joystick";
+ sensehat_joystick->keys_dev->phys = "sensehat-joystick/input0";
+ sensehat_joystick->keys_dev->id.bustype = BUS_I2C;
+
+ __set_bit(EV_KEY, sensehat_joystick->keys_dev->evbit);
+ __set_bit(EV_REP, sensehat_joystick->keys_dev->evbit);
+ for (i = 0; i < ARRAY_SIZE(keymap); i++)
+ __set_bit(keymap[i], sensehat_joystick->keys_dev->keybit);
+
+ error = input_register_device(sensehat_joystick->keys_dev);
+ if (error) {
+ dev_err(&pdev->dev, "Could not register input device");
+ return error;
+ }
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0)
+ return irq;
+
+ error = devm_request_threaded_irq(&pdev->dev, irq,
+ NULL, sensehat_joystick_report,
+ IRQF_ONESHOT, "keys",
+ sensehat_joystick);
+ if (error) {
+ dev_err(&pdev->dev, "IRQ request failed");
+ return error;
+ }
+
+ return 0;
+}
+
+static const struct of_device_id sensehat_joystick_device_id[] = {
+ { .compatible = "raspberrypi,sensehat-joystick" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, sensehat_joystick_device_id);
+
+static struct platform_driver sensehat_joystick_driver = {
+ .probe = sensehat_joystick_probe,
+ .driver = {
+ .name = "sensehat-joystick",
+ .of_match_table = sensehat_joystick_device_id,
+ },
+};
+
+module_platform_driver(sensehat_joystick_driver);
+
+MODULE_DESCRIPTION("Raspberry Pi Sense HAT joystick driver");
+MODULE_AUTHOR("Charles Mirabile <cmirabil@redhat.com>");
+MODULE_AUTHOR("Serge Schneider <serge@raspberrypi.org>");
+MODULE_LICENSE("GPL");