1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Driver for Phoenix RC Flight Controller Adapter 4 * 5 * Copyright (C) 2018 Marcus Folkesson <marcus.folkesson@gmail.com> 6 */ 7 8 #include <linux/kernel.h> 9 #include <linux/errno.h> 10 #include <linux/slab.h> 11 #include <linux/module.h> 12 #include <linux/uaccess.h> 13 #include <linux/usb.h> 14 #include <linux/usb/input.h> 15 #include <linux/mutex.h> 16 #include <linux/input.h> 17 18 #define PXRC_VENDOR_ID 0x1781 19 #define PXRC_PRODUCT_ID 0x0898 20 21 struct pxrc { 22 struct input_dev *input; 23 struct usb_interface *intf; 24 struct urb *urb; 25 struct mutex pm_mutex; 26 bool is_open; 27 char phys[64]; 28 }; 29 30 static void pxrc_usb_irq(struct urb *urb) 31 { 32 struct pxrc *pxrc = urb->context; 33 u8 *data = urb->transfer_buffer; 34 int error; 35 36 switch (urb->status) { 37 case 0: 38 /* success */ 39 break; 40 case -ETIME: 41 /* this urb is timing out */ 42 dev_dbg(&pxrc->intf->dev, 43 "%s - urb timed out - was the device unplugged?\n", 44 __func__); 45 return; 46 case -ECONNRESET: 47 case -ENOENT: 48 case -ESHUTDOWN: 49 case -EPIPE: 50 /* this urb is terminated, clean up */ 51 dev_dbg(&pxrc->intf->dev, "%s - urb shutting down with status: %d\n", 52 __func__, urb->status); 53 return; 54 default: 55 dev_dbg(&pxrc->intf->dev, "%s - nonzero urb status received: %d\n", 56 __func__, urb->status); 57 goto exit; 58 } 59 60 if (urb->actual_length == 8) { 61 input_report_abs(pxrc->input, ABS_X, data[0]); 62 input_report_abs(pxrc->input, ABS_Y, data[2]); 63 input_report_abs(pxrc->input, ABS_RX, data[3]); 64 input_report_abs(pxrc->input, ABS_RY, data[4]); 65 input_report_abs(pxrc->input, ABS_RUDDER, data[5]); 66 input_report_abs(pxrc->input, ABS_THROTTLE, data[6]); 67 input_report_abs(pxrc->input, ABS_MISC, data[7]); 68 69 input_report_key(pxrc->input, BTN_A, data[1]); 70 } 71 72 exit: 73 /* Resubmit to fetch new fresh URBs */ 74 error = usb_submit_urb(urb, GFP_ATOMIC); 75 if (error && error != -EPERM) 76 dev_err(&pxrc->intf->dev, 77 "%s - usb_submit_urb failed with result: %d", 78 __func__, error); 79 } 80 81 static int pxrc_open(struct input_dev *input) 82 { 83 struct pxrc *pxrc = input_get_drvdata(input); 84 int retval; 85 86 mutex_lock(&pxrc->pm_mutex); 87 retval = usb_submit_urb(pxrc->urb, GFP_KERNEL); 88 if (retval) { 89 dev_err(&pxrc->intf->dev, 90 "%s - usb_submit_urb failed, error: %d\n", 91 __func__, retval); 92 retval = -EIO; 93 goto out; 94 } 95 96 pxrc->is_open = true; 97 98 out: 99 mutex_unlock(&pxrc->pm_mutex); 100 return retval; 101 } 102 103 static void pxrc_close(struct input_dev *input) 104 { 105 struct pxrc *pxrc = input_get_drvdata(input); 106 107 mutex_lock(&pxrc->pm_mutex); 108 usb_kill_urb(pxrc->urb); 109 pxrc->is_open = false; 110 mutex_unlock(&pxrc->pm_mutex); 111 } 112 113 static void pxrc_free_urb(void *_pxrc) 114 { 115 struct pxrc *pxrc = _pxrc; 116 117 usb_free_urb(pxrc->urb); 118 } 119 120 static int pxrc_probe(struct usb_interface *intf, 121 const struct usb_device_id *id) 122 { 123 struct usb_device *udev = interface_to_usbdev(intf); 124 struct pxrc *pxrc; 125 struct usb_endpoint_descriptor *epirq; 126 size_t xfer_size; 127 void *xfer_buf; 128 int error; 129 130 /* 131 * Locate the endpoint information. This device only has an 132 * interrupt endpoint. 133 */ 134 error = usb_find_common_endpoints(intf->cur_altsetting, 135 NULL, NULL, &epirq, NULL); 136 if (error) { 137 dev_err(&intf->dev, "Could not find endpoint\n"); 138 return error; 139 } 140 141 pxrc = devm_kzalloc(&intf->dev, sizeof(*pxrc), GFP_KERNEL); 142 if (!pxrc) 143 return -ENOMEM; 144 145 mutex_init(&pxrc->pm_mutex); 146 pxrc->intf = intf; 147 148 usb_set_intfdata(pxrc->intf, pxrc); 149 150 xfer_size = usb_endpoint_maxp(epirq); 151 xfer_buf = devm_kmalloc(&intf->dev, xfer_size, GFP_KERNEL); 152 if (!xfer_buf) 153 return -ENOMEM; 154 155 pxrc->urb = usb_alloc_urb(0, GFP_KERNEL); 156 if (!pxrc->urb) 157 return -ENOMEM; 158 159 error = devm_add_action_or_reset(&intf->dev, pxrc_free_urb, pxrc); 160 if (error) 161 return error; 162 163 usb_fill_int_urb(pxrc->urb, udev, 164 usb_rcvintpipe(udev, epirq->bEndpointAddress), 165 xfer_buf, xfer_size, pxrc_usb_irq, pxrc, 1); 166 167 pxrc->input = devm_input_allocate_device(&intf->dev); 168 if (!pxrc->input) { 169 dev_err(&intf->dev, "couldn't allocate input device\n"); 170 return -ENOMEM; 171 } 172 173 pxrc->input->name = "PXRC Flight Controller Adapter"; 174 175 usb_make_path(udev, pxrc->phys, sizeof(pxrc->phys)); 176 strlcat(pxrc->phys, "/input0", sizeof(pxrc->phys)); 177 pxrc->input->phys = pxrc->phys; 178 179 usb_to_input_id(udev, &pxrc->input->id); 180 181 pxrc->input->open = pxrc_open; 182 pxrc->input->close = pxrc_close; 183 184 input_set_capability(pxrc->input, EV_KEY, BTN_A); 185 input_set_abs_params(pxrc->input, ABS_X, 0, 255, 0, 0); 186 input_set_abs_params(pxrc->input, ABS_Y, 0, 255, 0, 0); 187 input_set_abs_params(pxrc->input, ABS_RX, 0, 255, 0, 0); 188 input_set_abs_params(pxrc->input, ABS_RY, 0, 255, 0, 0); 189 input_set_abs_params(pxrc->input, ABS_RUDDER, 0, 255, 0, 0); 190 input_set_abs_params(pxrc->input, ABS_THROTTLE, 0, 255, 0, 0); 191 input_set_abs_params(pxrc->input, ABS_MISC, 0, 255, 0, 0); 192 193 input_set_drvdata(pxrc->input, pxrc); 194 195 error = input_register_device(pxrc->input); 196 if (error) 197 return error; 198 199 return 0; 200 } 201 202 static void pxrc_disconnect(struct usb_interface *intf) 203 { 204 /* All driver resources are devm-managed. */ 205 } 206 207 static int pxrc_suspend(struct usb_interface *intf, pm_message_t message) 208 { 209 struct pxrc *pxrc = usb_get_intfdata(intf); 210 211 mutex_lock(&pxrc->pm_mutex); 212 if (pxrc->is_open) 213 usb_kill_urb(pxrc->urb); 214 mutex_unlock(&pxrc->pm_mutex); 215 216 return 0; 217 } 218 219 static int pxrc_resume(struct usb_interface *intf) 220 { 221 struct pxrc *pxrc = usb_get_intfdata(intf); 222 int retval = 0; 223 224 mutex_lock(&pxrc->pm_mutex); 225 if (pxrc->is_open && usb_submit_urb(pxrc->urb, GFP_KERNEL) < 0) 226 retval = -EIO; 227 228 mutex_unlock(&pxrc->pm_mutex); 229 return retval; 230 } 231 232 static int pxrc_pre_reset(struct usb_interface *intf) 233 { 234 struct pxrc *pxrc = usb_get_intfdata(intf); 235 236 mutex_lock(&pxrc->pm_mutex); 237 usb_kill_urb(pxrc->urb); 238 return 0; 239 } 240 241 static int pxrc_post_reset(struct usb_interface *intf) 242 { 243 struct pxrc *pxrc = usb_get_intfdata(intf); 244 int retval = 0; 245 246 if (pxrc->is_open && usb_submit_urb(pxrc->urb, GFP_KERNEL) < 0) 247 retval = -EIO; 248 249 mutex_unlock(&pxrc->pm_mutex); 250 251 return retval; 252 } 253 254 static int pxrc_reset_resume(struct usb_interface *intf) 255 { 256 return pxrc_resume(intf); 257 } 258 259 static const struct usb_device_id pxrc_table[] = { 260 { USB_DEVICE(PXRC_VENDOR_ID, PXRC_PRODUCT_ID) }, 261 { } 262 }; 263 MODULE_DEVICE_TABLE(usb, pxrc_table); 264 265 static struct usb_driver pxrc_driver = { 266 .name = "pxrc", 267 .probe = pxrc_probe, 268 .disconnect = pxrc_disconnect, 269 .id_table = pxrc_table, 270 .suspend = pxrc_suspend, 271 .resume = pxrc_resume, 272 .pre_reset = pxrc_pre_reset, 273 .post_reset = pxrc_post_reset, 274 .reset_resume = pxrc_reset_resume, 275 }; 276 277 module_usb_driver(pxrc_driver); 278 279 MODULE_AUTHOR("Marcus Folkesson <marcus.folkesson@gmail.com>"); 280 MODULE_DESCRIPTION("PhoenixRC Flight Controller Adapter"); 281 MODULE_LICENSE("GPL v2"); 282