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