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 dprintk(x...) if (debug) printk(KERN_INFO DRIVER_NAME ": " x) 20 #define RXMASK_REGULAR 0x1 21 #define RXMASK_LEARNING 0x2 22 23 static bool debug; 24 25 struct loopback_dev { 26 struct rc_dev *dev; 27 u32 txmask; 28 u32 txcarrier; 29 u32 txduty; 30 bool idle; 31 bool learning; 32 bool carrierreport; 33 u32 rxcarriermin; 34 u32 rxcarriermax; 35 }; 36 37 static struct loopback_dev loopdev; 38 39 static int loop_set_tx_mask(struct rc_dev *dev, u32 mask) 40 { 41 struct loopback_dev *lodev = dev->priv; 42 43 if ((mask & (RXMASK_REGULAR | RXMASK_LEARNING)) != mask) { 44 dprintk("invalid tx mask: %u\n", mask); 45 return -EINVAL; 46 } 47 48 dprintk("setting tx mask: %u\n", mask); 49 lodev->txmask = mask; 50 return 0; 51 } 52 53 static int loop_set_tx_carrier(struct rc_dev *dev, u32 carrier) 54 { 55 struct loopback_dev *lodev = dev->priv; 56 57 dprintk("setting tx carrier: %u\n", carrier); 58 lodev->txcarrier = carrier; 59 return 0; 60 } 61 62 static int loop_set_tx_duty_cycle(struct rc_dev *dev, u32 duty_cycle) 63 { 64 struct loopback_dev *lodev = dev->priv; 65 66 if (duty_cycle < 1 || duty_cycle > 99) { 67 dprintk("invalid duty cycle: %u\n", duty_cycle); 68 return -EINVAL; 69 } 70 71 dprintk("setting duty cycle: %u\n", duty_cycle); 72 lodev->txduty = duty_cycle; 73 return 0; 74 } 75 76 static int loop_set_rx_carrier_range(struct rc_dev *dev, u32 min, u32 max) 77 { 78 struct loopback_dev *lodev = dev->priv; 79 80 if (min < 1 || min > max) { 81 dprintk("invalid rx carrier range %u to %u\n", min, max); 82 return -EINVAL; 83 } 84 85 dprintk("setting rx carrier range %u to %u\n", min, max); 86 lodev->rxcarriermin = min; 87 lodev->rxcarriermax = max; 88 return 0; 89 } 90 91 static int loop_tx_ir(struct rc_dev *dev, unsigned *txbuf, unsigned count) 92 { 93 struct loopback_dev *lodev = dev->priv; 94 u32 rxmask; 95 unsigned i; 96 struct ir_raw_event rawir = {}; 97 98 if (lodev->txcarrier < lodev->rxcarriermin || 99 lodev->txcarrier > lodev->rxcarriermax) { 100 dprintk("ignoring tx, carrier out of range\n"); 101 goto out; 102 } 103 104 if (lodev->learning) 105 rxmask = RXMASK_LEARNING; 106 else 107 rxmask = RXMASK_REGULAR; 108 109 if (!(rxmask & lodev->txmask)) { 110 dprintk("ignoring tx, rx mask mismatch\n"); 111 goto out; 112 } 113 114 for (i = 0; i < count; i++) { 115 rawir.pulse = i % 2 ? false : true; 116 rawir.duration = txbuf[i]; 117 if (rawir.duration) 118 ir_raw_event_store_with_filter(dev, &rawir); 119 } 120 121 /* Fake a silence long enough to cause us to go idle */ 122 rawir.pulse = false; 123 rawir.duration = dev->timeout; 124 ir_raw_event_store_with_filter(dev, &rawir); 125 126 ir_raw_event_handle(dev); 127 128 out: 129 return count; 130 } 131 132 static void loop_set_idle(struct rc_dev *dev, bool enable) 133 { 134 struct loopback_dev *lodev = dev->priv; 135 136 if (lodev->idle != enable) { 137 dprintk("%sing idle mode\n", enable ? "enter" : "exit"); 138 lodev->idle = enable; 139 } 140 } 141 142 static int loop_set_learning_mode(struct rc_dev *dev, int enable) 143 { 144 struct loopback_dev *lodev = dev->priv; 145 146 if (lodev->learning != enable) { 147 dprintk("%sing learning mode\n", enable ? "enter" : "exit"); 148 lodev->learning = !!enable; 149 } 150 151 return 0; 152 } 153 154 static int loop_set_carrier_report(struct rc_dev *dev, int enable) 155 { 156 struct loopback_dev *lodev = dev->priv; 157 158 if (lodev->carrierreport != enable) { 159 dprintk("%sabling carrier reports\n", enable ? "en" : "dis"); 160 lodev->carrierreport = !!enable; 161 } 162 163 return 0; 164 } 165 166 static int loop_set_wakeup_filter(struct rc_dev *dev, 167 struct rc_scancode_filter *sc) 168 { 169 static const unsigned int max = 512; 170 struct ir_raw_event *raw; 171 int ret; 172 int i; 173 174 /* fine to disable filter */ 175 if (!sc->mask) 176 return 0; 177 178 /* encode the specified filter and loop it back */ 179 raw = kmalloc_array(max, sizeof(*raw), GFP_KERNEL); 180 if (!raw) 181 return -ENOMEM; 182 183 ret = ir_raw_encode_scancode(dev->wakeup_protocol, sc->data, raw, max); 184 /* still loop back the partial raw IR even if it's incomplete */ 185 if (ret == -ENOBUFS) 186 ret = max; 187 if (ret >= 0) { 188 /* do the loopback */ 189 for (i = 0; i < ret; ++i) 190 ir_raw_event_store(dev, &raw[i]); 191 ir_raw_event_handle(dev); 192 193 ret = 0; 194 } 195 196 kfree(raw); 197 198 return ret; 199 } 200 201 static int __init loop_init(void) 202 { 203 struct rc_dev *rc; 204 int ret; 205 206 rc = rc_allocate_device(RC_DRIVER_IR_RAW); 207 if (!rc) { 208 printk(KERN_ERR DRIVER_NAME ": rc_dev allocation failed\n"); 209 return -ENOMEM; 210 } 211 212 rc->device_name = "rc-core loopback device"; 213 rc->input_phys = "rc-core/virtual"; 214 rc->input_id.bustype = BUS_VIRTUAL; 215 rc->input_id.version = 1; 216 rc->driver_name = DRIVER_NAME; 217 rc->map_name = RC_MAP_EMPTY; 218 rc->priv = &loopdev; 219 rc->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER; 220 rc->allowed_wakeup_protocols = RC_PROTO_BIT_ALL_IR_ENCODER; 221 rc->encode_wakeup = true; 222 rc->timeout = MS_TO_US(100); /* 100 ms */ 223 rc->min_timeout = 1; 224 rc->max_timeout = UINT_MAX; 225 rc->rx_resolution = 1; 226 rc->tx_resolution = 1; 227 rc->s_tx_mask = loop_set_tx_mask; 228 rc->s_tx_carrier = loop_set_tx_carrier; 229 rc->s_tx_duty_cycle = loop_set_tx_duty_cycle; 230 rc->s_rx_carrier_range = loop_set_rx_carrier_range; 231 rc->tx_ir = loop_tx_ir; 232 rc->s_idle = loop_set_idle; 233 rc->s_learning_mode = loop_set_learning_mode; 234 rc->s_carrier_report = loop_set_carrier_report; 235 rc->s_wakeup_filter = loop_set_wakeup_filter; 236 237 loopdev.txmask = RXMASK_REGULAR; 238 loopdev.txcarrier = 36000; 239 loopdev.txduty = 50; 240 loopdev.rxcarriermin = 1; 241 loopdev.rxcarriermax = ~0; 242 loopdev.idle = true; 243 loopdev.learning = false; 244 loopdev.carrierreport = false; 245 246 ret = rc_register_device(rc); 247 if (ret < 0) { 248 printk(KERN_ERR DRIVER_NAME ": rc_dev registration failed\n"); 249 rc_free_device(rc); 250 return ret; 251 } 252 253 loopdev.dev = rc; 254 return 0; 255 } 256 257 static void __exit loop_exit(void) 258 { 259 rc_unregister_device(loopdev.dev); 260 } 261 262 module_init(loop_init); 263 module_exit(loop_exit); 264 265 module_param(debug, bool, S_IRUGO | S_IWUSR); 266 MODULE_PARM_DESC(debug, "Enable debug messages"); 267 268 MODULE_DESCRIPTION("Loopback device for rc-core debugging"); 269 MODULE_AUTHOR("David Härdeman <david@hardeman.nu>"); 270 MODULE_LICENSE("GPL"); 271