HID: rapoo: Add support for side buttons on RAPOO 0x2015 mouse

This patch adds support for handling the side buttons
on the RAPOO 0x2015 wireless mouse. These buttons were
previously not generating input events due to missing
driver logic.

The new code handles raw HID input report with Report
ID 1 and maps the side buttons to KEY_BACK and KEY_FORWARD
using the input subsystem.

Tested on a RAPOO mouse with USB ID 24AE:2015.

Signed-off-by: Nguyen Dinh Dang Duong <dangduong31205@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>

drivers/hid/Kconfig

@@ -1015,6 +1015,12 @@ config HID_PXRC
        To compile this driver as a module, choose M here: the
        module will be called hid-pxrc.
 
+config HID_RAPOO
+	tristate "Rapoo non-fully HID-compliant devices"
+	help
+	Support for Rapoo devices that are not fully compliant with the
+	HID standard.
+
 config HID_RAZER
 	tristate "Razer non-fully HID-compliant devices"
 	help

drivers/hid/Makefile

@@ -113,6 +113,7 @@ obj-$(CONFIG_HID_PLANTRONICS)	+= hid-plantronics.o
 obj-$(CONFIG_HID_PLAYSTATION)	+= hid-playstation.o
 obj-$(CONFIG_HID_PRIMAX)	+= hid-primax.o
 obj-$(CONFIG_HID_PXRC)		+= hid-pxrc.o
+obj-$(CONFIG_HID_RAPOO) += hid-rapoo.o
 obj-$(CONFIG_HID_RAZER)	+= hid-razer.o
 obj-$(CONFIG_HID_REDRAGON)	+= hid-redragon.o
 obj-$(CONFIG_HID_RETRODE)	+= hid-retrode.o

drivers/hid/hid-ids.h

@@ -1166,6 +1166,9 @@
 #define I2C_PRODUCT_ID_RAYDIUM_4B33	0x4b33
 #define I2C_PRODUCT_ID_RAYDIUM_3118	0x3118
 
+#define USB_VENDOR_ID_RAPOO			0x24ae
+#define USB_DEVICE_ID_RAPOO_2_4G_RECEIVER	0x2015
+
 #define USB_VENDOR_ID_RAZER            0x1532
 #define USB_DEVICE_ID_RAZER_BLACKWIDOW_ULTIMATE   0x010D
 #define USB_DEVICE_ID_RAZER_BLACKWIDOW            0x010e

drivers/hid/hid-rapoo.c

@@ -0,0 +1,101 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <asm-generic/errno-base.h>
+#include <asm-generic/int-ll64.h>
+#include <linux/bitops.h>
+#include <linux/input.h>
+#include <linux/input-event-codes.h>
+#include <linux/module.h>
+#include <linux/hid.h>
+#include <linux/usb.h>
+
+#include "hid-ids.h"
+
+#define RAPOO_BTN_BACK			0x08
+#define RAPOO_BTN_FORWARD		0x10
+
+static const struct hid_device_id rapoo_devices[] = {
+	{ HID_USB_DEVICE(USB_VENDOR_ID_RAPOO, USB_DEVICE_ID_RAPOO_2_4G_RECEIVER) },
+	{ }
+};
+MODULE_DEVICE_TABLE(hid, rapoo_devices);
+
+static int rapoo_probe(struct hid_device *hdev, const struct hid_device_id *id)
+{
+	int ret;
+	struct input_dev *input;
+
+	ret = hid_parse(hdev);
+	if (ret) {
+		hid_err(hdev, "parse failed\n");
+		return ret;
+	}
+
+	ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
+	if (ret) {
+		hid_err(hdev, "start failed\n");
+		return ret;
+	}
+
+	if (hdev->bus == BUS_USB) {
+		struct usb_interface *intf = to_usb_interface(hdev->dev.parent);
+
+		if (intf->cur_altsetting->desc.bInterfaceNumber != 1)
+			return 0;
+	}
+
+	input = devm_input_allocate_device(&hdev->dev);
+	if (!input)
+		return -ENOMEM;
+
+	input->name = "Rapoo 2.4G Wireless Mouse";
+	input->phys = "rapoo/input1";
+	input->id.bustype = hdev->bus;
+	input->id.vendor = hdev->vendor;
+	input->id.product = hdev->product;
+	input->id.version = hdev->version;
+
+	__set_bit(EV_KEY, input->evbit);
+	__set_bit(KEY_BACK, input->keybit);
+	__set_bit(KEY_FORWARD, input->keybit);
+
+	ret = input_register_device(input);
+	if (ret)
+		return ret;
+
+	hid_set_drvdata(hdev, input);
+
+	return ret;
+}
+
+static int rapoo_raw_event(struct hid_device *hdev, struct hid_report *report, u8 *data, int size)
+{
+	struct input_dev *input = hid_get_drvdata(hdev);
+
+	if (!input)
+		return 0;
+
+	if (report->id == 1 && size >= 2) {
+		u8 btn = data[1];
+
+		input_report_key(input, KEY_BACK, btn & RAPOO_BTN_BACK);
+		input_report_key(input, KEY_FORWARD, btn & RAPOO_BTN_FORWARD);
+		input_sync(input);
+		return 1;
+	}
+
+	return 0;
+}
+
+static struct hid_driver rapoo_driver = {
+	.name = "hid-rapoo",
+	.id_table = rapoo_devices,
+	.probe = rapoo_probe,
+	.raw_event = rapoo_raw_event,
+};
+
+module_hid_driver(rapoo_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Nguyen Dinh Dang Duong <dangduong31205@gmail.com>");
+MODULE_DESCRIPTION("RAPOO 2.4G Wireless Device Driver");
+