1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * HID driver for PhoenixRC 8-axis flight controller 4 * 5 * Copyright (C) 2022 Marcus Folkesson <marcus.folkesson@gmail.com> 6 */ 7 8 #include <linux/device.h> 9 #include <linux/hid.h> 10 #include <linux/module.h> 11 12 #include "hid-ids.h" 13 14 struct pxrc_priv { 15 u8 slider; 16 u8 dial; 17 bool alternate; 18 }; 19 20 static const __u8 pxrc_rdesc_fixed[] = { 21 0x05, 0x01, // Usage Page (Generic Desktop Ctrls) 22 0x09, 0x04, // Usage (Joystick) 23 0xA1, 0x01, // Collection (Application) 24 0x09, 0x01, // Usage (Pointer) 25 0xA1, 0x00, // Collection (Physical) 26 0x09, 0x30, // Usage (X) 27 0x09, 0x36, // Usage (Slider) 28 0x09, 0x31, // Usage (Y) 29 0x09, 0x32, // Usage (Z) 30 0x09, 0x33, // Usage (Rx) 31 0x09, 0x34, // Usage (Ry) 32 0x09, 0x35, // Usage (Rz) 33 0x09, 0x37, // Usage (Dial) 34 0x15, 0x00, // Logical Minimum (0) 35 0x26, 0xFF, 0x00, // Logical Maximum (255) 36 0x35, 0x00, // Physical Minimum (0) 37 0x46, 0xFF, 0x00, // Physical Maximum (255) 38 0x75, 0x08, // Report Size (8) 39 0x95, 0x08, // Report Count (8) 40 0x81, 0x02, // Input (Data,Var,Abs,No Wrap,Linear,Preferred State,No Null Position) 41 0xC0, // End Collection 42 0xC0, // End Collection 43 }; 44 45 static const __u8 *pxrc_report_fixup(struct hid_device *hdev, __u8 *rdesc, 46 unsigned int *rsize) 47 { 48 hid_info(hdev, "fixing up PXRC report descriptor\n"); 49 *rsize = sizeof(pxrc_rdesc_fixed); 50 return pxrc_rdesc_fixed; 51 } 52 53 static int pxrc_raw_event(struct hid_device *hdev, struct hid_report *report, 54 u8 *data, int size) 55 { 56 struct pxrc_priv *priv = hid_get_drvdata(hdev); 57 58 if (size < 8) 59 return 0; 60 61 if (priv->alternate) 62 priv->slider = data[7]; 63 else 64 priv->dial = data[7]; 65 66 data[1] = priv->slider; 67 data[7] = priv->dial; 68 69 priv->alternate = !priv->alternate; 70 return 0; 71 } 72 73 static int pxrc_probe(struct hid_device *hdev, const struct hid_device_id *id) 74 { 75 int ret; 76 struct pxrc_priv *priv; 77 78 priv = devm_kzalloc(&hdev->dev, sizeof(*priv), GFP_KERNEL); 79 if (!priv) 80 return -ENOMEM; 81 hid_set_drvdata(hdev, priv); 82 83 ret = hid_parse(hdev); 84 if (ret) { 85 hid_err(hdev, "parse failed\n"); 86 return ret; 87 } 88 89 ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT); 90 if (ret) { 91 hid_err(hdev, "hw start failed\n"); 92 return ret; 93 } 94 95 return 0; 96 } 97 98 static const struct hid_device_id pxrc_devices[] = { 99 { HID_USB_DEVICE(USB_VENDOR_ID_MULTIPLE_1781, USB_DEVICE_ID_PHOENIXRC) }, 100 { /* sentinel */ } 101 }; 102 MODULE_DEVICE_TABLE(hid, pxrc_devices); 103 104 static struct hid_driver pxrc_driver = { 105 .name = "hid-pxrc", 106 .id_table = pxrc_devices, 107 .report_fixup = pxrc_report_fixup, 108 .probe = pxrc_probe, 109 .raw_event = pxrc_raw_event, 110 }; 111 module_hid_driver(pxrc_driver); 112 113 MODULE_AUTHOR("Marcus Folkesson <marcus.folkesson@gmail.com>"); 114 MODULE_DESCRIPTION("HID driver for PXRC 8-axis flight controller"); 115 MODULE_LICENSE("GPL"); 116