[PATCH v8 2/6] drivers/input/joystick: sensehat: Raspberry Pi Sense HAT joystick driver
Charles Mirabile
cmirabil at redhat.com
Tue Apr 12 13:13:39 PDT 2022
This patch adds the driver for the Sense HAT joystick. It outputs BTN_DPAD
key events when moved in any of the four directions and the BTN_SELECT
event when depressed.
Co-developed-by: Daniel Bauman <dbauman at redhat.com>
Signed-off-by: Daniel Bauman <dbauman at redhat.com>
Co-developed-by: Mwesigwa Guma <mguma at redhat.com>
Signed-off-by: Mwesigwa Guma <mguma at redhat.com>
Co-developed-by: Joel Savitz <jsavitz at redhat.com>
Signed-off-by: Joel Savitz <jsavitz at redhat.com>
Signed-off-by: Charles Mirabile <cmirabil at redhat.com>
---
drivers/input/joystick/Kconfig | 11 ++
drivers/input/joystick/Makefile | 1 +
drivers/input/joystick/sensehat-joystick.c | 137 +++++++++++++++++++++
3 files changed, 149 insertions(+)
create mode 100644 drivers/input/joystick/sensehat-joystick.c
diff --git a/drivers/input/joystick/Kconfig b/drivers/input/joystick/Kconfig
index 3b23078bc7b5..505a032e2786 100644
--- a/drivers/input/joystick/Kconfig
+++ b/drivers/input/joystick/Kconfig
@@ -399,4 +399,15 @@ config JOYSTICK_N64
Say Y here if you want enable support for the four
built-in controller ports on the Nintendo 64 console.
+config JOYSTICK_SENSEHAT
+ tristate "Raspberry Pi Sense HAT joystick"
+ depends on INPUT && I2C
+ select MFD_SIMPLE_MFD_I2C
+ help
+ Say Y here if you want to enable the driver for the
+ the Raspberry Pi Sense HAT.
+
+ To compile this driver as a module, choose M here: the
+ module will be called sensehat_joystick.
+
endif
diff --git a/drivers/input/joystick/Makefile b/drivers/input/joystick/Makefile
index 5174b8aba2dd..39c8b5c6e5ae 100644
--- a/drivers/input/joystick/Makefile
+++ b/drivers/input/joystick/Makefile
@@ -28,6 +28,7 @@ obj-$(CONFIG_JOYSTICK_N64) += n64joy.o
obj-$(CONFIG_JOYSTICK_PSXPAD_SPI) += psxpad-spi.o
obj-$(CONFIG_JOYSTICK_PXRC) += pxrc.o
obj-$(CONFIG_JOYSTICK_QWIIC) += qwiic-joystick.o
+obj-$(CONFIG_JOYSTICK_SENSEHAT) += sensehat-joystick.o
obj-$(CONFIG_JOYSTICK_SIDEWINDER) += sidewinder.o
obj-$(CONFIG_JOYSTICK_SPACEBALL) += spaceball.o
obj-$(CONFIG_JOYSTICK_SPACEORB) += spaceorb.o
diff --git a/drivers/input/joystick/sensehat-joystick.c b/drivers/input/joystick/sensehat-joystick.c
new file mode 100644
index 000000000000..6fed6004f464
--- /dev/null
+++ b/drivers/input/joystick/sensehat-joystick.c
@@ -0,0 +1,137 @@
+// 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 n, void *cookie)
+{
+ int i, error, keys;
+ struct sensehat_joystick *sensehat_joystick = cookie;
+ unsigned long curr_states, changes;
+
+ 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)
+{
+ int error, i, irq;
+ struct sensehat_joystick *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(sensehat_joystick->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;
+ }
+
+ for (i = 0; i < ARRAY_SIZE(keymap); i++)
+ set_bit(keymap[i], sensehat_joystick->keys_dev->keybit);
+
+ 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;
+ sensehat_joystick->keys_dev->evbit[0] =
+ BIT_MASK(EV_KEY) | BIT_MASK(EV_REP);
+
+ 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) {
+ dev_err(&pdev->dev, "Could not retrieve interrupt request.");
+ 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 at redhat.com>");
+MODULE_AUTHOR("Serge Schneider <serge at raspberrypi.org>");
+MODULE_LICENSE("GPL");
--
2.31.1
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