1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * Loopback driver for rc-core, |
4 | * |
5 | * Copyright (c) 2010 David Härdeman <david@hardeman.nu> |
6 | * |
7 | * This driver receives TX data and passes it back as RX data, |
8 | * which is useful for (scripted) debugging of rc-core without |
9 | * having to use actual hardware. |
10 | */ |
11 | |
12 | #include <linux/device.h> |
13 | #include <linux/module.h> |
14 | #include <linux/sched.h> |
15 | #include <linux/slab.h> |
16 | #include <media/rc-core.h> |
17 | |
18 | #define DRIVER_NAME "rc-loopback" |
19 | #define RXMASK_NARROWBAND 0x1 |
20 | #define RXMASK_WIDEBAND 0x2 |
21 | |
22 | struct loopback_dev { |
23 | struct rc_dev *dev; |
24 | u32 txmask; |
25 | u32 txcarrier; |
26 | u32 txduty; |
27 | bool idle; |
28 | bool wideband; |
29 | bool carrierreport; |
30 | u32 rxcarriermin; |
31 | u32 rxcarriermax; |
32 | }; |
33 | |
34 | static struct loopback_dev loopdev; |
35 | |
36 | static int loop_set_tx_mask(struct rc_dev *dev, u32 mask) |
37 | { |
38 | struct loopback_dev *lodev = dev->priv; |
39 | |
40 | if ((mask & (RXMASK_NARROWBAND | RXMASK_WIDEBAND)) != mask) { |
41 | dev_dbg(&dev->dev, "invalid tx mask: %u\n" , mask); |
42 | return 2; |
43 | } |
44 | |
45 | dev_dbg(&dev->dev, "setting tx mask: %u\n" , mask); |
46 | lodev->txmask = mask; |
47 | return 0; |
48 | } |
49 | |
50 | static int loop_set_tx_carrier(struct rc_dev *dev, u32 carrier) |
51 | { |
52 | struct loopback_dev *lodev = dev->priv; |
53 | |
54 | dev_dbg(&dev->dev, "setting tx carrier: %u\n" , carrier); |
55 | lodev->txcarrier = carrier; |
56 | return 0; |
57 | } |
58 | |
59 | static int loop_set_tx_duty_cycle(struct rc_dev *dev, u32 duty_cycle) |
60 | { |
61 | struct loopback_dev *lodev = dev->priv; |
62 | |
63 | if (duty_cycle < 1 || duty_cycle > 99) { |
64 | dev_dbg(&dev->dev, "invalid duty cycle: %u\n" , duty_cycle); |
65 | return -EINVAL; |
66 | } |
67 | |
68 | dev_dbg(&dev->dev, "setting duty cycle: %u\n" , duty_cycle); |
69 | lodev->txduty = duty_cycle; |
70 | return 0; |
71 | } |
72 | |
73 | static int loop_set_rx_carrier_range(struct rc_dev *dev, u32 min, u32 max) |
74 | { |
75 | struct loopback_dev *lodev = dev->priv; |
76 | |
77 | if (min < 1 || min > max) { |
78 | dev_dbg(&dev->dev, "invalid rx carrier range %u to %u\n" , min, max); |
79 | return -EINVAL; |
80 | } |
81 | |
82 | dev_dbg(&dev->dev, "setting rx carrier range %u to %u\n" , min, max); |
83 | lodev->rxcarriermin = min; |
84 | lodev->rxcarriermax = max; |
85 | return 0; |
86 | } |
87 | |
88 | static int loop_tx_ir(struct rc_dev *dev, unsigned *txbuf, unsigned count) |
89 | { |
90 | struct loopback_dev *lodev = dev->priv; |
91 | u32 rxmask; |
92 | unsigned i; |
93 | struct ir_raw_event rawir = {}; |
94 | |
95 | if (lodev->txcarrier < lodev->rxcarriermin || |
96 | lodev->txcarrier > lodev->rxcarriermax) { |
97 | dev_dbg(&dev->dev, "ignoring tx, carrier out of range\n" ); |
98 | goto out; |
99 | } |
100 | |
101 | if (lodev->wideband) |
102 | rxmask = RXMASK_WIDEBAND; |
103 | else |
104 | rxmask = RXMASK_NARROWBAND; |
105 | |
106 | if (!(rxmask & lodev->txmask)) { |
107 | dev_dbg(&dev->dev, "ignoring tx, rx mask mismatch\n" ); |
108 | goto out; |
109 | } |
110 | |
111 | for (i = 0; i < count; i++) { |
112 | rawir.pulse = i % 2 ? false : true; |
113 | rawir.duration = txbuf[i]; |
114 | |
115 | /* simulate overflow if ridiculously long pulse was sent */ |
116 | if (rawir.pulse && rawir.duration > MS_TO_US(50)) |
117 | ir_raw_event_overflow(dev); |
118 | else |
119 | ir_raw_event_store_with_filter(dev, ev: &rawir); |
120 | } |
121 | |
122 | if (lodev->carrierreport) { |
123 | rawir.pulse = false; |
124 | rawir.carrier_report = true; |
125 | rawir.carrier = lodev->txcarrier; |
126 | |
127 | ir_raw_event_store(dev, ev: &rawir); |
128 | } |
129 | |
130 | /* Fake a silence long enough to cause us to go idle */ |
131 | rawir.pulse = false; |
132 | rawir.duration = dev->timeout; |
133 | ir_raw_event_store_with_filter(dev, ev: &rawir); |
134 | |
135 | ir_raw_event_handle(dev); |
136 | |
137 | out: |
138 | return count; |
139 | } |
140 | |
141 | static void loop_set_idle(struct rc_dev *dev, bool enable) |
142 | { |
143 | struct loopback_dev *lodev = dev->priv; |
144 | |
145 | if (lodev->idle != enable) { |
146 | dev_dbg(&dev->dev, "%sing idle mode\n" , enable ? "enter" : "exit" ); |
147 | lodev->idle = enable; |
148 | } |
149 | } |
150 | |
151 | static int loop_set_wideband_receiver(struct rc_dev *dev, int enable) |
152 | { |
153 | struct loopback_dev *lodev = dev->priv; |
154 | |
155 | if (lodev->wideband != enable) { |
156 | dev_dbg(&dev->dev, "using %sband receiver\n" , enable ? "wide" : "narrow" ); |
157 | lodev->wideband = !!enable; |
158 | } |
159 | |
160 | return 0; |
161 | } |
162 | |
163 | static int loop_set_carrier_report(struct rc_dev *dev, int enable) |
164 | { |
165 | struct loopback_dev *lodev = dev->priv; |
166 | |
167 | if (lodev->carrierreport != enable) { |
168 | dev_dbg(&dev->dev, "%sabling carrier reports\n" , enable ? "en" : "dis" ); |
169 | lodev->carrierreport = !!enable; |
170 | } |
171 | |
172 | return 0; |
173 | } |
174 | |
175 | static int loop_set_wakeup_filter(struct rc_dev *dev, |
176 | struct rc_scancode_filter *sc) |
177 | { |
178 | static const unsigned int max = 512; |
179 | struct ir_raw_event *raw; |
180 | int ret; |
181 | int i; |
182 | |
183 | /* fine to disable filter */ |
184 | if (!sc->mask) |
185 | return 0; |
186 | |
187 | /* encode the specified filter and loop it back */ |
188 | raw = kmalloc_array(n: max, size: sizeof(*raw), GFP_KERNEL); |
189 | if (!raw) |
190 | return -ENOMEM; |
191 | |
192 | ret = ir_raw_encode_scancode(protocol: dev->wakeup_protocol, scancode: sc->data, events: raw, max); |
193 | /* still loop back the partial raw IR even if it's incomplete */ |
194 | if (ret == -ENOBUFS) |
195 | ret = max; |
196 | if (ret >= 0) { |
197 | /* do the loopback */ |
198 | for (i = 0; i < ret; ++i) |
199 | ir_raw_event_store(dev, ev: &raw[i]); |
200 | ir_raw_event_handle(dev); |
201 | |
202 | ret = 0; |
203 | } |
204 | |
205 | kfree(objp: raw); |
206 | |
207 | return ret; |
208 | } |
209 | |
210 | static int __init loop_init(void) |
211 | { |
212 | struct rc_dev *rc; |
213 | int ret; |
214 | |
215 | rc = rc_allocate_device(RC_DRIVER_IR_RAW); |
216 | if (!rc) |
217 | return -ENOMEM; |
218 | |
219 | rc->device_name = "rc-core loopback device" ; |
220 | rc->input_phys = "rc-core/virtual" ; |
221 | rc->input_id.bustype = BUS_VIRTUAL; |
222 | rc->input_id.version = 1; |
223 | rc->driver_name = DRIVER_NAME; |
224 | rc->map_name = RC_MAP_EMPTY; |
225 | rc->priv = &loopdev; |
226 | rc->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER; |
227 | rc->allowed_wakeup_protocols = RC_PROTO_BIT_ALL_IR_ENCODER; |
228 | rc->encode_wakeup = true; |
229 | rc->timeout = IR_DEFAULT_TIMEOUT; |
230 | rc->min_timeout = 1; |
231 | rc->max_timeout = IR_MAX_TIMEOUT; |
232 | rc->rx_resolution = 1; |
233 | rc->tx_resolution = 1; |
234 | rc->s_tx_mask = loop_set_tx_mask; |
235 | rc->s_tx_carrier = loop_set_tx_carrier; |
236 | rc->s_tx_duty_cycle = loop_set_tx_duty_cycle; |
237 | rc->s_rx_carrier_range = loop_set_rx_carrier_range; |
238 | rc->tx_ir = loop_tx_ir; |
239 | rc->s_idle = loop_set_idle; |
240 | rc->s_wideband_receiver = loop_set_wideband_receiver; |
241 | rc->s_carrier_report = loop_set_carrier_report; |
242 | rc->s_wakeup_filter = loop_set_wakeup_filter; |
243 | |
244 | loopdev.txmask = RXMASK_NARROWBAND; |
245 | loopdev.txcarrier = 36000; |
246 | loopdev.txduty = 50; |
247 | loopdev.rxcarriermin = 1; |
248 | loopdev.rxcarriermax = ~0; |
249 | loopdev.idle = true; |
250 | loopdev.wideband = false; |
251 | loopdev.carrierreport = false; |
252 | |
253 | ret = rc_register_device(dev: rc); |
254 | if (ret < 0) { |
255 | dev_err(&rc->dev, "rc_dev registration failed\n" ); |
256 | rc_free_device(dev: rc); |
257 | return ret; |
258 | } |
259 | |
260 | loopdev.dev = rc; |
261 | return 0; |
262 | } |
263 | |
264 | static void __exit loop_exit(void) |
265 | { |
266 | rc_unregister_device(dev: loopdev.dev); |
267 | } |
268 | |
269 | module_init(loop_init); |
270 | module_exit(loop_exit); |
271 | |
272 | MODULE_DESCRIPTION("Loopback device for rc-core debugging" ); |
273 | MODULE_AUTHOR("David Härdeman <david@hardeman.nu>" ); |
274 | MODULE_LICENSE("GPL" ); |
275 | |