diff mbox series

[v4,3/10] HID: hid-appletb-kbd: add support for fn toggle between media and function mode

Message ID 16F62213-44A2-47FF-95DA-E496EE6CD1D1@live.com (mailing list archive)
State Superseded
Delegated to: Jiri Kosina
Headers show
Series Touch Bar support for T2 Macs | expand

Commit Message

Aditya Garg Aug. 10, 2024, 8:48 a.m. UTC
From: Aditya Garg <gargaditya08@live.com>

This patch adds support for the switching between the Media and Function
keys on the touchbar by pressing the Fn key on Apple Internal Keyboard.

Signed-off-by: Aditya Garg <gargaditya08@live.com>
---
drivers/hid/hid-appletb-kbd.c | 128 ++++++++++++++++++++++++++++++++++
1 file changed, 128 insertions(+)
diff mbox series

Patch

diff --git a/drivers/hid/hid-appletb-kbd.c b/drivers/hid/hid-appletb-kbd.c
index ecac68fc7..442c4d884 100644
--- a/drivers/hid/hid-appletb-kbd.c
+++ b/drivers/hid/hid-appletb-kbd.c
@@ -26,6 +26,8 @@ 
#define APPLETB_KBD_MODE_OFF	3
#define APPLETB_KBD_MODE_MAX	APPLETB_KBD_MODE_OFF

+#define APPLETB_DEVID_KEYBOARD	1
+
#define HID_USAGE_MODE		0x00ff0004

static int appletb_tb_def_mode = APPLETB_KBD_MODE_SPCL;
@@ -35,11 +37,18 @@  MODULE_PARM_DESC(mode, "Default touchbar mode:\n"
			 "    1 - function-keys\n"
			 "    [2] - special keys");

+static bool appletb_tb_fn_toggle = true;
+module_param_named(fntoggle, appletb_tb_fn_toggle, bool, 0644);
+MODULE_PARM_DESC(fntoggle, "Switch between Fn and media controls on pressing Fn key");
+
struct appletb_kbd {
	struct hid_field *mode_field;

	u8 saved_mode;
	u8 current_mode;
+	struct input_handler inp_handler;
+	struct input_handle kbd_handle;
+
};

static const struct key_entry appletb_kbd_keymap[] = {
@@ -172,6 +181,75 @@  static int appletb_kbd_hid_event(struct hid_device *hdev, struct hid_field *fiel
	return kbd->current_mode == APPLETB_KBD_MODE_OFF;
}

+static void appletb_kbd_inp_event(struct input_handle *handle, unsigned int type,
+			      unsigned int code, int value)
+{
+	struct appletb_kbd *kbd = handle->private;
+
+	if (type == EV_KEY && code == KEY_FN && appletb_tb_fn_toggle) {
+		if (value == 1) {
+			kbd->saved_mode = kbd->current_mode;
+			if (kbd->current_mode == APPLETB_KBD_MODE_SPCL)
+				appletb_kbd_set_mode(kbd, APPLETB_KBD_MODE_FN);
+			else if (kbd->current_mode == APPLETB_KBD_MODE_FN)
+				appletb_kbd_set_mode(kbd, APPLETB_KBD_MODE_SPCL);
+		} else if (value == 0) {
+			if (kbd->saved_mode != kbd->current_mode)
+				appletb_kbd_set_mode(kbd, kbd->saved_mode);
+		}
+	}
+}
+
+static int appletb_kbd_inp_connect(struct input_handler *handler,
+			       struct input_dev *dev,
+			       const struct input_device_id *id)
+{
+	struct appletb_kbd *kbd = handler->private;
+	struct input_handle *handle;
+	int rc;
+
+	if (id->driver_info == APPLETB_DEVID_KEYBOARD) {
+		handle = &kbd->kbd_handle;
+		handle->name = "tbkbd";
+	} else {
+		return -ENOENT;
+	}
+
+	if (handle->dev)
+		return -EEXIST;
+
+	handle->open = 0;
+	handle->dev = input_get_device(dev);
+	handle->handler = handler;
+	handle->private = kbd;
+
+	rc = input_register_handle(handle);
+	if (rc)
+		goto err_free_dev;
+
+	rc = input_open_device(handle);
+	if (rc)
+		goto err_unregister_handle;
+
+	return 0;
+
+ err_unregister_handle:
+	input_unregister_handle(handle);
+ err_free_dev:
+	input_put_device(handle->dev);
+	handle->dev = NULL;
+	return rc;
+}
+
+static void appletb_kbd_inp_disconnect(struct input_handle *handle)
+{
+	input_close_device(handle);
+	input_unregister_handle(handle);
+
+	input_put_device(handle->dev);
+	handle->dev = NULL;
+}
+
static int appletb_kbd_input_configured(struct hid_device *hdev, struct hid_input *hidinput)
{
	int idx;
@@ -196,6 +274,40 @@  static int appletb_kbd_input_configured(struct hid_device *hdev, struct hid_inpu
	return 0;
}

+static const struct input_device_id appletb_kbd_input_devices[] = {
+	{
+		.flags = INPUT_DEVICE_ID_MATCH_BUS |
+			INPUT_DEVICE_ID_MATCH_VENDOR |
+			INPUT_DEVICE_ID_MATCH_KEYBIT,
+		.bustype = BUS_USB,
+		.vendor = USB_VENDOR_ID_APPLE,
+		.keybit = { [BIT_WORD(KEY_FN)] = BIT_MASK(KEY_FN) },
+		.driver_info = APPLETB_DEVID_KEYBOARD,
+	},
+	{ }
+};
+
+static bool appletb_kbd_match_internal_device(struct input_handler *handler,
+					  struct input_dev *inp_dev)
+{
+	struct device *dev = &inp_dev->dev;
+
+	/* in kernel: dev && !is_usb_device(dev) */
+	while (dev && !(dev->type && dev->type->name &&
+			!strcmp(dev->type->name, "usb_device")))
+		dev = dev->parent;
+
+	/*
+	 * Apple labels all their internal keyboards and trackpads as such,
+	 * instead of maintaining an ever expanding list of product-id's we
+	 * just look at the device's product name.
+	 */
+	if (dev)
+		return !!strstr(to_usb_device(dev)->product, "Internal Keyboard");
+
+	return false;
+}
+
static int appletb_kbd_probe(struct hid_device *hdev, const struct hid_device_id *id)
{
	struct appletb_kbd *kbd;
@@ -228,6 +340,20 @@  static int appletb_kbd_probe(struct hid_device *hdev, const struct hid_device_id
		goto stop_hw;
	}

+	kbd->inp_handler.event = appletb_kbd_inp_event;
+	kbd->inp_handler.connect = appletb_kbd_inp_connect;
+	kbd->inp_handler.disconnect = appletb_kbd_inp_disconnect;
+	kbd->inp_handler.name = "appletb";
+	kbd->inp_handler.id_table = appletb_kbd_input_devices;
+	kbd->inp_handler.match = appletb_kbd_match_internal_device;
+	kbd->inp_handler.private = kbd;
+
+	ret = input_register_handler(&kbd->inp_handler);
+	if (ret) {
+		dev_err_probe(dev, ret, "Unable to register keyboard handler\n");
+		goto close_hw;
+	}
+
	ret = appletb_kbd_set_mode(kbd, appletb_tb_def_mode);
	if (ret) {
		dev_err_probe(dev, ret, "Failed to set touchbar mode\n");
@@ -251,6 +377,8 @@  static void appletb_kbd_remove(struct hid_device *hdev)

	appletb_kbd_set_mode(kbd, APPLETB_KBD_MODE_OFF);

+	input_unregister_handler(&kbd->inp_handler);
+
	hid_hw_close(hdev);
	hid_hw_stop(hdev);
}