[PATCH v5] staging: HID: Add ShanWan USB WirelessGamepad driver

[Mubashshir <ahmubashshir@gmail.com>]

This device has a quirky initialization process.
Depending on how it was initialized, behaves completely differently.
In default mode, it behaves as expected, but in fallback it disables
force-feedback, analog stick configurations and L3/R3.

Different OEMs manufactures joypads with same vid:pid but different
axis/button mapping[1], and I don't know which one has which layout,
so, we'll let hid-core figure that out, and handle only FF here.

 * The one I have has different axis layout than the one of Huseyin.

Signed-off-by: Huseyin BIYIK <huseyinbiyik@hotmail.com>
Signed-off-by: Mubashshir <ahmubashshir@gmail.com>
---
v5: Use hid_{get,set}_drvdata to pass data to `->play()`

 drivers/hid/Kconfig       |  19 +++++
 drivers/hid/Makefile      |   1 +
 drivers/hid/hid-ids.h     |   3 +
 drivers/hid/hid-shanwan.c | 145 ++++++++++++++++++++++++++++++++++++++
 4 files changed, 168 insertions(+)
 create mode 100644 drivers/hid/hid-shanwan.c

diff --git a/drivers/hid/Kconfig b/drivers/hid/Kconfig
index 4ce012f83253..e6c8aa855252 100644
--- a/drivers/hid/Kconfig
+++ b/drivers/hid/Kconfig
@@ -990,6 +990,25 @@ config HID_SEMITEK
 	- Woo-dy
 	- X-Bows Nature/Knight
 
+config HID_SHANWAN
+	tristate "ShanWan USB WirelessGamepad"
+	depends on USB_HID
+	help
+	Support for Shanwan USB WirelessGamepad (and clones).
+
+	This device has a quirky initialization process.
+	Depending on how it was initialized, it behaves completely differently.
+	In default mode, it behaves as expected, but in fallback it disables
+	force-feedback, analog stick configurations and L3/R3.
+
+config SHANWAN_FF
+	bool "ShanWan USB WirelessGamepad force feedback support"
+	depends on HID_SHANWAN
+	select INPUT_FF_MEMLESS
+	help
+	Say Y here if you have a ShanWan USB WirelessGamepad and want to enable
+	force feedback support for it.
+
 config HID_SIGMAMICRO
 	tristate "SiGma Micro-based keyboards"
 	depends on USB_HID
diff --git a/drivers/hid/Makefile b/drivers/hid/Makefile
index 5d37cacbde33..52878455fc10 100644
--- a/drivers/hid/Makefile
+++ b/drivers/hid/Makefile
@@ -116,6 +116,7 @@ obj-$(CONFIG_HID_RMI)		+= hid-rmi.o
 obj-$(CONFIG_HID_SAITEK)	+= hid-saitek.o
 obj-$(CONFIG_HID_SAMSUNG)	+= hid-samsung.o
 obj-$(CONFIG_HID_SEMITEK)	+= hid-semitek.o
+obj-$(CONFIG_HID_SHANWAN)	+= hid-shanwan.o
 obj-$(CONFIG_HID_SIGMAMICRO)	+= hid-sigmamicro.o
 obj-$(CONFIG_HID_SMARTJOYPLUS)	+= hid-sjoy.o
 obj-$(CONFIG_HID_SONY)		+= hid-sony.o
diff --git a/drivers/hid/hid-ids.h b/drivers/hid/hid-ids.h
index d79e946acdcb..04c3324dc453 100644
--- a/drivers/hid/hid-ids.h
+++ b/drivers/hid/hid-ids.h
@@ -627,6 +627,9 @@
 #define USB_PRODUCT_ID_HP_PIXART_OEM_USB_OPTICAL_MOUSE_0641	0x0641
 #define USB_PRODUCT_ID_HP_PIXART_OEM_USB_OPTICAL_MOUSE_1f4a	0x1f4a
 
+#define USB_VENDOR_ID_SHANWAN 0x2563
+#define USB_PRODUCT_ID_SHANWAN_USB_WIRELESSGAMEPAD 0x0575
+
 #define USB_VENDOR_ID_HUION		0x256c
 #define USB_DEVICE_ID_HUION_TABLET	0x006e
 #define USB_DEVICE_ID_HUION_TABLET2	0x006d
diff --git a/drivers/hid/hid-shanwan.c b/drivers/hid/hid-shanwan.c
new file mode 100644
index 000000000000..c80bfcac5dc7
--- /dev/null
+++ b/drivers/hid/hid-shanwan.c
@@ -0,0 +1,145 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Force feedback support for Shanwan USB WirelessGamepad
+ *
+ * Copyright (c) 2022-2023	Huseyin BIYIK	<huseyinbiyik@hotmail.com>
+ * Copyright (c) 2023	Ahmad Hasan Mubashshir	<ahmubashshir@gmail.com>
+ *
+ */
+
+#include <linux/input.h>
+#include <linux/slab.h>
+#include <linux/hid.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/string.h>
+
+#include "hid-ids.h"
+
+static bool swap_motors;
+module_param_named(swap, swap_motors, bool, 0);
+MODULE_PARM_DESC(swap, "Swap Weak/Strong Feedback motors");
+
+#ifdef CONFIG_SHANWAN_FF
+static int shanwan_play_effect(struct input_dev *dev, void *data, struct ff_effect *effect)
+{
+	struct hid_device *hid    = input_get_drvdata(dev);
+	struct hid_report *report = hid_get_drvdata(hid);
+	struct hid_field  *field0 = report->field[0];
+	s32 payload_template[] = {
+		0x02,  // 2 = rumble effect message
+		0x08, // reserved value, always 8
+		0x00, // rumble value
+		0x00, // rumble value
+		0xff  // duration 0-254 (255 = nonstop)
+	};
+
+	if (effect->type != FF_RUMBLE)
+		return 0;
+
+	memcpy_and_pad(field0->value,
+		       (sizeof(s32) * 8),
+		       payload_template,
+		       (sizeof(s32) * 4),
+		       0x00);
+
+	if (swap_motors) {
+		/* weak rumble / strong rumble */
+		field0->value[2] = effect->u.rumble.strong_magnitude / 256;
+		field0->value[3] = effect->u.rumble.weak_magnitude / 256;
+	} else {
+		/* strong rumble / weak rumble */
+		field0->value[2] = effect->u.rumble.weak_magnitude / 256;
+		field0->value[3] = effect->u.rumble.strong_magnitude / 256;
+	}
+
+	hid_hw_request(hid, report, HID_REQ_SET_REPORT);
+
+	return 0;
+}
+
+static int shanwan_init_ff(struct hid_device *hid)
+{
+	struct hid_report *report;
+	struct hid_input *hidinput;
+	struct list_head *report_list = &hid->report_enum[HID_OUTPUT_REPORT].report_list;
+	struct input_dev *dev;
+
+	if (list_empty(&hid->inputs)) {
+		hid_err(hid, "no inputs found\n");
+		return -ENODEV;
+	}
+	hidinput = list_first_entry(&hid->inputs, struct hid_input, list);
+	dev = hidinput->input;
+
+	if (list_empty(report_list)) {
+		hid_err(hid, "no output reports found\n");
+		return -ENODEV;
+	}
+
+	report = list_first_entry(report_list, struct hid_report, list);
+	hid_set_drvdata(hid, report);
+
+	set_bit(FF_RUMBLE, dev->ffbit);
+	if (input_ff_create_memless(dev, NULL, shanwan_play_effect))
+		return -ENODEV;
+
+	return 0;
+}
+#else
+static int shanwan_init_ff(struct hid_device *hid)
+{
+	return 0;
+}
+#endif
+
+static int shanwan_probe(struct hid_device *hdev, const struct hid_device_id *id)
+{
+	int ret;
+
+	ret = hid_parse(hdev);
+	if (ret) {
+		hid_err(hdev, "parse failed\n");
+		return ret;
+	}
+
+	ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT & ~HID_CONNECT_FF);
+	if (ret) {
+		hid_err(hdev, "hw start failed\n");
+		return ret;
+	}
+
+	ret = shanwan_init_ff(hdev);
+	if (ret)
+		hid_warn(hdev, "Failed to enable force feedback support, error: %d\n", ret);
+
+	ret = hid_hw_open(hdev);
+	if (ret) {
+		dev_err(&hdev->dev, "hw open failed\n");
+		hid_hw_stop(hdev);
+		return ret;
+	}
+
+	hid_hw_close(hdev);
+	return ret;
+}
+
+static const struct hid_device_id shanwan_devices[] = {
+	{ HID_USB_DEVICE(USB_VENDOR_ID_SHANWAN, USB_PRODUCT_ID_SHANWAN_USB_WIRELESSGAMEPAD) },
+	{ }
+};
+MODULE_DEVICE_TABLE(hid, shanwan_devices);
+
+static struct hid_driver shanwan_driver = {
+	.name			= "shanwan",
+	.id_table		= shanwan_devices,
+	.probe			= shanwan_probe,
+};
+module_hid_driver(shanwan_driver);
+
+MODULE_AUTHOR("Huseyin BIYIK <huseyinbiyik@hotmail.com>");
+MODULE_AUTHOR("Ahmad Hasan Mubashshir <ahmubashshir@gmail.com>");
+MODULE_DESCRIPTION("Force feedback support for Shanwan USB WirelessGamepad");
+MODULE_LICENSE("GPL");
+
+// vim: ts=8:noet
-- 
2.40.1