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
21struct 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
30static 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
72exit:
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
81static 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
98out:
99 mutex_unlock(&pxrc->pm_mutex);
100 return retval;
101}
102
103static 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
113static void pxrc_free_urb(void *_pxrc)
114{
115 struct pxrc *pxrc = _pxrc;
116
117 usb_free_urb(pxrc->urb);
118}
119
120static 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
202static void pxrc_disconnect(struct usb_interface *intf)
203{
204 /* All driver resources are devm-managed. */
205}
206
207static 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
219static 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
232static 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
241static 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
254static int pxrc_reset_resume(struct usb_interface *intf)
255{
256 return pxrc_resume(intf);
257}
258
259static const struct usb_device_id pxrc_table[] = {
260 { USB_DEVICE(PXRC_VENDOR_ID, PXRC_PRODUCT_ID) },
261 { }
262};
263MODULE_DEVICE_TABLE(usb, pxrc_table);
264
265static 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
277module_usb_driver(pxrc_driver);
278
279MODULE_AUTHOR("Marcus Folkesson <marcus.folkesson@gmail.com>");
280MODULE_DESCRIPTION("PhoenixRC Flight Controller Adapter");
281MODULE_LICENSE("GPL v2");
282