// SPDX-License-Identifier: GPL-2.0-or-later /* * Loopback driver for rc-core, * * Copyright (c) 2010 David Härdeman * * This driver receives TX data and passes it back as RX data, * which is useful for (scripted) debugging of rc-core without * having to use actual hardware. */ #include #include #include #include #include #define DRIVER_NAME "rc-loopback" #define RXMASK_NARROWBAND 0x1 #define RXMASK_WIDEBAND 0x2 struct loopback_dev { struct rc_dev *dev; u32 txmask; u32 txcarrier; u32 txduty; bool idle; bool wideband; bool carrierreport; u32 rxcarriermin; u32 rxcarriermax; }; static struct loopback_dev loopdev; static int loop_set_tx_mask(struct rc_dev *dev, u32 mask) { struct loopback_dev *lodev = dev->priv; if ((mask & (RXMASK_NARROWBAND | RXMASK_WIDEBAND)) != mask) { dev_dbg(&dev->dev, "invalid tx mask: %u\n", mask); return 2; } dev_dbg(&dev->dev, "setting tx mask: %u\n", mask); lodev->txmask = mask; return 0; } static int loop_set_tx_carrier(struct rc_dev *dev, u32 carrier) { struct loopback_dev *lodev = dev->priv; dev_dbg(&dev->dev, "setting tx carrier: %u\n", carrier); lodev->txcarrier = carrier; return 0; } static int loop_set_tx_duty_cycle(struct rc_dev *dev, u32 duty_cycle) { struct loopback_dev *lodev = dev->priv; if (duty_cycle < 1 || duty_cycle > 99) { dev_dbg(&dev->dev, "invalid duty cycle: %u\n", duty_cycle); return -EINVAL; } dev_dbg(&dev->dev, "setting duty cycle: %u\n", duty_cycle); lodev->txduty = duty_cycle; return 0; } static int loop_set_rx_carrier_range(struct rc_dev *dev, u32 min, u32 max) { struct loopback_dev *lodev = dev->priv; if (min < 1 || min > max) { dev_dbg(&dev->dev, "invalid rx carrier range %u to %u\n", min, max); return -EINVAL; } dev_dbg(&dev->dev, "setting rx carrier range %u to %u\n", min, max); lodev->rxcarriermin = min; lodev->rxcarriermax = max; return 0; } static int loop_tx_ir(struct rc_dev *dev, unsigned *txbuf, unsigned count) { struct loopback_dev *lodev = dev->priv; u32 rxmask; unsigned i; struct ir_raw_event rawir = {}; if (lodev->txcarrier < lodev->rxcarriermin || lodev->txcarrier > lodev->rxcarriermax) { dev_dbg(&dev->dev, "ignoring tx, carrier out of range\n"); goto out; } if (lodev->wideband) rxmask = RXMASK_WIDEBAND; else rxmask = RXMASK_NARROWBAND; if (!(rxmask & lodev->txmask)) { dev_dbg(&dev->dev, "ignoring tx, rx mask mismatch\n"); goto out; } for (i = 0; i < count; i++) { rawir.pulse = i % 2 ? false : true; rawir.duration = txbuf[i]; /* simulate overflow if ridiculously long pulse was sent */ if (rawir.pulse && rawir.duration > MS_TO_US(50)) ir_raw_event_overflow(dev); else ir_raw_event_store_with_filter(dev, &rawir); } if (lodev->carrierreport) { rawir.pulse = false; rawir.carrier_report = true; rawir.carrier = lodev->txcarrier; ir_raw_event_store(dev, &rawir); } /* Fake a silence long enough to cause us to go idle */ rawir.pulse = false; rawir.duration = dev->timeout; ir_raw_event_store_with_filter(dev, &rawir); ir_raw_event_handle(dev); out: return count; } static void loop_set_idle(struct rc_dev *dev, bool enable) { struct loopback_dev *lodev = dev->priv; if (lodev->idle != enable) { dev_dbg(&dev->dev, "%sing idle mode\n", enable ? "enter" : "exit"); lodev->idle = enable; } } static int loop_set_wideband_receiver(struct rc_dev *dev, int enable) { struct loopback_dev *lodev = dev->priv; if (lodev->wideband != enable) { dev_dbg(&dev->dev, "using %sband receiver\n", enable ? "wide" : "narrow"); lodev->wideband = !!enable; } return 0; } static int loop_set_carrier_report(struct rc_dev *dev, int enable) { struct loopback_dev *lodev = dev->priv; if (lodev->carrierreport != enable) { dev_dbg(&dev->dev, "%sabling carrier reports\n", enable ? "en" : "dis"); lodev->carrierreport = !!enable; } return 0; } static int loop_set_wakeup_filter(struct rc_dev *dev, struct rc_scancode_filter *sc) { static const unsigned int max = 512; struct ir_raw_event *raw; int ret; int i; /* fine to disable filter */ if (!sc->mask) return 0; /* encode the specified filter and loop it back */ raw = kmalloc_array(max, sizeof(*raw), GFP_KERNEL); if (!raw) return -ENOMEM; ret = ir_raw_encode_scancode(dev->wakeup_protocol, sc->data, raw, max); /* still loop back the partial raw IR even if it's incomplete */ if (ret == -ENOBUFS) ret = max; if (ret >= 0) { /* do the loopback */ for (i = 0; i < ret; ++i) ir_raw_event_store(dev, &raw[i]); ir_raw_event_handle(dev); ret = 0; } kfree(raw); return ret; } static int __init loop_init(void) { struct rc_dev *rc; int ret; rc = rc_allocate_device(RC_DRIVER_IR_RAW); if (!rc) return -ENOMEM; rc->device_name = "rc-core loopback device"; rc->input_phys = "rc-core/virtual"; rc->input_id.bustype = BUS_VIRTUAL; rc->input_id.version = 1; rc->driver_name = DRIVER_NAME; rc->map_name = RC_MAP_EMPTY; rc->priv = &loopdev; rc->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER; rc->allowed_wakeup_protocols = RC_PROTO_BIT_ALL_IR_ENCODER; rc->encode_wakeup = true; rc->timeout = IR_DEFAULT_TIMEOUT; rc->min_timeout = 1; rc->max_timeout = IR_MAX_TIMEOUT; rc->rx_resolution = 1; rc->tx_resolution = 1; rc->s_tx_mask = loop_set_tx_mask; rc->s_tx_carrier = loop_set_tx_carrier; rc->s_tx_duty_cycle = loop_set_tx_duty_cycle; rc->s_rx_carrier_range = loop_set_rx_carrier_range; rc->tx_ir = loop_tx_ir; rc->s_idle = loop_set_idle; rc->s_wideband_receiver = loop_set_wideband_receiver; rc->s_carrier_report = loop_set_carrier_report; rc->s_wakeup_filter = loop_set_wakeup_filter; loopdev.txmask = RXMASK_NARROWBAND; loopdev.txcarrier = 36000; loopdev.txduty = 50; loopdev.rxcarriermin = 1; loopdev.rxcarriermax = ~0; loopdev.idle = true; loopdev.wideband = false; loopdev.carrierreport = false; ret = rc_register_device(rc); if (ret < 0) { dev_err(&rc->dev, "rc_dev registration failed\n"); rc_free_device(rc); return ret; } loopdev.dev = rc; return 0; } static void __exit loop_exit(void) { rc_unregister_device(loopdev.dev); } module_init(loop_init); module_exit(loop_exit); MODULE_DESCRIPTION("Loopback device for rc-core debugging"); MODULE_AUTHOR("David Härdeman "); MODULE_LICENSE("GPL");