xref: /openbmc/linux/drivers/media/rc/rc-loopback.c (revision afb46f79)
1 /*
2  * Loopback driver for rc-core,
3  *
4  * Copyright (c) 2010 David Härdeman <david@hardeman.nu>
5  *
6  * This driver receives TX data and passes it back as RX data,
7  * which is useful for (scripted) debugging of rc-core without
8  * having to use actual hardware.
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation; either version 2 of the License, or
13  * (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  * GNU General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with this program; if not, write to the Free Software
22  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23  *
24  */
25 
26 #include <linux/device.h>
27 #include <linux/module.h>
28 #include <linux/sched.h>
29 #include <media/rc-core.h>
30 
31 #define DRIVER_NAME	"rc-loopback"
32 #define dprintk(x...)	if (debug) printk(KERN_INFO DRIVER_NAME ": " x)
33 #define RXMASK_REGULAR	0x1
34 #define RXMASK_LEARNING	0x2
35 
36 static bool debug;
37 
38 struct loopback_dev {
39 	struct rc_dev *dev;
40 	u32 txmask;
41 	u32 txcarrier;
42 	u32 txduty;
43 	bool idle;
44 	bool learning;
45 	bool carrierreport;
46 	u32 rxcarriermin;
47 	u32 rxcarriermax;
48 };
49 
50 static struct loopback_dev loopdev;
51 
52 static int loop_set_tx_mask(struct rc_dev *dev, u32 mask)
53 {
54 	struct loopback_dev *lodev = dev->priv;
55 
56 	if ((mask & (RXMASK_REGULAR | RXMASK_LEARNING)) != mask) {
57 		dprintk("invalid tx mask: %u\n", mask);
58 		return -EINVAL;
59 	}
60 
61 	dprintk("setting tx mask: %u\n", mask);
62 	lodev->txmask = mask;
63 	return 0;
64 }
65 
66 static int loop_set_tx_carrier(struct rc_dev *dev, u32 carrier)
67 {
68 	struct loopback_dev *lodev = dev->priv;
69 
70 	dprintk("setting tx carrier: %u\n", carrier);
71 	lodev->txcarrier = carrier;
72 	return 0;
73 }
74 
75 static int loop_set_tx_duty_cycle(struct rc_dev *dev, u32 duty_cycle)
76 {
77 	struct loopback_dev *lodev = dev->priv;
78 
79 	if (duty_cycle < 1 || duty_cycle > 99) {
80 		dprintk("invalid duty cycle: %u\n", duty_cycle);
81 		return -EINVAL;
82 	}
83 
84 	dprintk("setting duty cycle: %u\n", duty_cycle);
85 	lodev->txduty = duty_cycle;
86 	return 0;
87 }
88 
89 static int loop_set_rx_carrier_range(struct rc_dev *dev, u32 min, u32 max)
90 {
91 	struct loopback_dev *lodev = dev->priv;
92 
93 	if (min < 1 || min > max) {
94 		dprintk("invalid rx carrier range %u to %u\n", min, max);
95 		return -EINVAL;
96 	}
97 
98 	dprintk("setting rx carrier range %u to %u\n", min, max);
99 	lodev->rxcarriermin = min;
100 	lodev->rxcarriermax = max;
101 	return 0;
102 }
103 
104 static int loop_tx_ir(struct rc_dev *dev, unsigned *txbuf, unsigned count)
105 {
106 	struct loopback_dev *lodev = dev->priv;
107 	u32 rxmask;
108 	unsigned i;
109 	DEFINE_IR_RAW_EVENT(rawir);
110 
111 	if (lodev->txcarrier < lodev->rxcarriermin ||
112 	    lodev->txcarrier > lodev->rxcarriermax) {
113 		dprintk("ignoring tx, carrier out of range\n");
114 		goto out;
115 	}
116 
117 	if (lodev->learning)
118 		rxmask = RXMASK_LEARNING;
119 	else
120 		rxmask = RXMASK_REGULAR;
121 
122 	if (!(rxmask & lodev->txmask)) {
123 		dprintk("ignoring tx, rx mask mismatch\n");
124 		goto out;
125 	}
126 
127 	for (i = 0; i < count; i++) {
128 		rawir.pulse = i % 2 ? false : true;
129 		rawir.duration = txbuf[i] * 1000;
130 		if (rawir.duration)
131 			ir_raw_event_store_with_filter(dev, &rawir);
132 	}
133 
134 	/* Fake a silence long enough to cause us to go idle */
135 	rawir.pulse = false;
136 	rawir.duration = dev->timeout;
137 	ir_raw_event_store_with_filter(dev, &rawir);
138 
139 	ir_raw_event_handle(dev);
140 
141 out:
142 	return count;
143 }
144 
145 static void loop_set_idle(struct rc_dev *dev, bool enable)
146 {
147 	struct loopback_dev *lodev = dev->priv;
148 
149 	if (lodev->idle != enable) {
150 		dprintk("%sing idle mode\n", enable ? "enter" : "exit");
151 		lodev->idle = enable;
152 	}
153 }
154 
155 static int loop_set_learning_mode(struct rc_dev *dev, int enable)
156 {
157 	struct loopback_dev *lodev = dev->priv;
158 
159 	if (lodev->learning != enable) {
160 		dprintk("%sing learning mode\n", enable ? "enter" : "exit");
161 		lodev->learning = !!enable;
162 	}
163 
164 	return 0;
165 }
166 
167 static int loop_set_carrier_report(struct rc_dev *dev, int enable)
168 {
169 	struct loopback_dev *lodev = dev->priv;
170 
171 	if (lodev->carrierreport != enable) {
172 		dprintk("%sabling carrier reports\n", enable ? "en" : "dis");
173 		lodev->carrierreport = !!enable;
174 	}
175 
176 	return 0;
177 }
178 
179 static int __init loop_init(void)
180 {
181 	struct rc_dev *rc;
182 	int ret;
183 
184 	rc = rc_allocate_device();
185 	if (!rc) {
186 		printk(KERN_ERR DRIVER_NAME ": rc_dev allocation failed\n");
187 		return -ENOMEM;
188 	}
189 
190 	rc->input_name		= "rc-core loopback device";
191 	rc->input_phys		= "rc-core/virtual";
192 	rc->input_id.bustype	= BUS_VIRTUAL;
193 	rc->input_id.version	= 1;
194 	rc->driver_name		= DRIVER_NAME;
195 	rc->map_name		= RC_MAP_EMPTY;
196 	rc->priv		= &loopdev;
197 	rc->driver_type		= RC_DRIVER_IR_RAW;
198 	rc_set_allowed_protocols(rc, RC_BIT_ALL);
199 	rc->timeout		= 100 * 1000 * 1000; /* 100 ms */
200 	rc->min_timeout		= 1;
201 	rc->max_timeout		= UINT_MAX;
202 	rc->rx_resolution	= 1000;
203 	rc->tx_resolution	= 1000;
204 	rc->s_tx_mask		= loop_set_tx_mask;
205 	rc->s_tx_carrier	= loop_set_tx_carrier;
206 	rc->s_tx_duty_cycle	= loop_set_tx_duty_cycle;
207 	rc->s_rx_carrier_range	= loop_set_rx_carrier_range;
208 	rc->tx_ir		= loop_tx_ir;
209 	rc->s_idle		= loop_set_idle;
210 	rc->s_learning_mode	= loop_set_learning_mode;
211 	rc->s_carrier_report	= loop_set_carrier_report;
212 
213 	loopdev.txmask		= RXMASK_REGULAR;
214 	loopdev.txcarrier	= 36000;
215 	loopdev.txduty		= 50;
216 	loopdev.rxcarriermin	= 1;
217 	loopdev.rxcarriermax	= ~0;
218 	loopdev.idle		= true;
219 	loopdev.learning	= false;
220 	loopdev.carrierreport	= false;
221 
222 	ret = rc_register_device(rc);
223 	if (ret < 0) {
224 		printk(KERN_ERR DRIVER_NAME ": rc_dev registration failed\n");
225 		rc_free_device(rc);
226 		return ret;
227 	}
228 
229 	loopdev.dev = rc;
230 	return 0;
231 }
232 
233 static void __exit loop_exit(void)
234 {
235 	rc_unregister_device(loopdev.dev);
236 }
237 
238 module_init(loop_init);
239 module_exit(loop_exit);
240 
241 module_param(debug, bool, S_IRUGO | S_IWUSR);
242 MODULE_PARM_DESC(debug, "Enable debug messages");
243 
244 MODULE_DESCRIPTION("Loopback device for rc-core debugging");
245 MODULE_AUTHOR("David Härdeman <david@hardeman.nu>");
246 MODULE_LICENSE("GPL");
247