xref: /linux/drivers/media/usb/au0828/au0828-input.c (revision 3932b9ca55b0be314a36d3e84faff3e823c081f5)
1 /*
2   handle au0828 IR remotes via linux kernel input layer.
3 
4    Copyright (C) 2014 Mauro Carvalho Chehab <mchehab@samsung.com>
5    Copyright (c) 2014 Samsung Electronics Co., Ltd.
6 
7   Based on em28xx-input.c.
8 
9   This program is free software; you can redistribute it and/or modify
10   it under the terms of the GNU General Public License as published by
11   the Free Software Foundation; either version 2 of the License, or
12   (at your option) any later version.
13 
14   This program is distributed in the hope that it will be useful,
15   but WITHOUT ANY WARRANTY; without even the implied warranty of
16   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17   GNU General Public License for more details.
18  */
19 
20 #include <linux/module.h>
21 #include <linux/init.h>
22 #include <linux/delay.h>
23 #include <linux/interrupt.h>
24 #include <linux/usb.h>
25 #include <linux/slab.h>
26 #include <media/rc-core.h>
27 
28 #include "au0828.h"
29 
30 struct au0828_rc {
31 	struct au0828_dev *dev;
32 	struct rc_dev *rc;
33 	char name[32];
34 	char phys[32];
35 
36 	/* poll decoder */
37 	int polling;
38 	struct delayed_work work;
39 
40 	/* i2c slave address of external device (if used) */
41 	u16 i2c_dev_addr;
42 
43 	int  (*get_key_i2c)(struct au0828_rc *ir);
44 };
45 
46 /*
47  * AU8522 has a builtin IR receiver. Add functions to get IR from it
48  */
49 
50 static int au8522_rc_write(struct au0828_rc *ir, u16 reg, u8 data)
51 {
52 	int rc;
53 	char buf[] = { (reg >> 8) | 0x80, reg & 0xff, data };
54 	struct i2c_msg msg = { .addr = ir->i2c_dev_addr, .flags = 0,
55 			       .buf = buf, .len = sizeof(buf) };
56 
57 	rc = i2c_transfer(ir->dev->i2c_client.adapter, &msg, 1);
58 
59 	if (rc < 0)
60 		return rc;
61 
62 	return (rc == 1) ? 0 : -EIO;
63 }
64 
65 static int au8522_rc_read(struct au0828_rc *ir, u16 reg, int val,
66 				 char *buf, int size)
67 {
68 	int rc;
69 	char obuf[3];
70 	struct i2c_msg msg[2] = { { .addr = ir->i2c_dev_addr, .flags = 0,
71 				    .buf = obuf, .len = 2 },
72 				  { .addr = ir->i2c_dev_addr, .flags = I2C_M_RD,
73 				    .buf = buf, .len = size } };
74 
75 	obuf[0] = 0x40 | reg >> 8;
76 	obuf[1] = reg & 0xff;
77 	if (val >= 0) {
78 		obuf[2] = val;
79 		msg[0].len++;
80 	}
81 
82 	rc = i2c_transfer(ir->dev->i2c_client.adapter, msg, 2);
83 
84 	if (rc < 0)
85 		return rc;
86 
87 	return (rc == 2) ? 0 : -EIO;
88 }
89 
90 static int au8522_rc_andor(struct au0828_rc *ir, u16 reg, u8 mask, u8 value)
91 {
92 	int rc;
93 	char buf;
94 
95 	rc = au8522_rc_read(ir, reg, -1, &buf, 1);
96 	if (rc < 0)
97 		return rc;
98 
99 	buf = (buf & ~mask) | (value & mask);
100 
101 	return au8522_rc_write(ir, reg, buf);
102 }
103 
104 #define au8522_rc_set(ir, reg, bit) au8522_rc_andor(ir, (reg), (bit), (bit))
105 #define au8522_rc_clear(ir, reg, bit) au8522_rc_andor(ir, (reg), (bit), 0)
106 
107 /* Remote Controller time units */
108 
109 #define AU8522_UNIT		200000 /* ns */
110 #define NEC_START_SPACE		(4500000 / AU8522_UNIT)
111 #define NEC_START_PULSE		(562500 * 16)
112 #define RC5_START_SPACE		(4 * AU8522_UNIT)
113 #define RC5_START_PULSE		888888
114 
115 static int au0828_get_key_au8522(struct au0828_rc *ir)
116 {
117 	unsigned char buf[40];
118 	DEFINE_IR_RAW_EVENT(rawir);
119 	int i, j, rc;
120 	int prv_bit, bit, width;
121 	bool first = true;
122 
123 	/* Check IR int */
124 	rc = au8522_rc_read(ir, 0xe1, -1, buf, 1);
125 	if (rc < 0 || !(buf[0] & (1 << 4)))
126 		return 0;
127 
128 	/* Something arrived. Get the data */
129 	rc = au8522_rc_read(ir, 0xe3, 0x11, buf, sizeof(buf));
130 
131 
132 	if (rc < 0)
133 		return rc;
134 
135 	/* Disable IR */
136 	au8522_rc_clear(ir, 0xe0, 1 << 4);
137 
138 	usleep_range(45000, 46000);
139 
140 	/* Enable IR */
141 	au8522_rc_set(ir, 0xe0, 1 << 4);
142 
143 	dprintk(16, "RC data received: %*ph\n", 40, buf);
144 
145 	prv_bit = (buf[0] >> 7) & 0x01;
146 	width = 0;
147 	for (i = 0; i < sizeof(buf); i++) {
148 		for (j = 7; j >= 0; j--) {
149 			bit = (buf[i] >> j) & 0x01;
150 			if (bit == prv_bit) {
151 				width++;
152 				continue;
153 			}
154 
155 			/*
156 			 * Fix an au8522 bug: the first pulse event
157 			 * is lost. So, we need to fake it, based on the
158 			 * protocol. That means that not all raw decoders
159 			 * will work, as we need to add a hack for each
160 			 * protocol, based on the first space.
161 			 * So, we only support RC5 and NEC.
162 			 */
163 
164 			if (first) {
165 				first = false;
166 
167 				init_ir_raw_event(&rawir);
168 				rawir.pulse = true;
169 				if (width > NEC_START_SPACE - 2 &&
170 				    width < NEC_START_SPACE + 2) {
171 					/* NEC protocol */
172 					rawir.duration = NEC_START_PULSE;
173 					dprintk(16, "Storing NEC start %s with duration %d",
174 						rawir.pulse ? "pulse" : "space",
175 						rawir.duration);
176 				} else {
177 					/* RC5 protocol */
178 					rawir.duration = RC5_START_PULSE;
179 					dprintk(16, "Storing RC5 start %s with duration %d",
180 						rawir.pulse ? "pulse" : "space",
181 						rawir.duration);
182 				}
183 				ir_raw_event_store(ir->rc, &rawir);
184 			}
185 
186 			init_ir_raw_event(&rawir);
187 			rawir.pulse = prv_bit ? false : true;
188 			rawir.duration = AU8522_UNIT * width;
189 			dprintk(16, "Storing %s with duration %d",
190 				rawir.pulse ? "pulse" : "space",
191 				rawir.duration);
192 			ir_raw_event_store(ir->rc, &rawir);
193 
194 			width = 1;
195 			prv_bit = bit;
196 		}
197 	}
198 
199 	init_ir_raw_event(&rawir);
200 	rawir.pulse = prv_bit ? false : true;
201 	rawir.duration = AU8522_UNIT * width;
202 	dprintk(16, "Storing end %s with duration %d",
203 		rawir.pulse ? "pulse" : "space",
204 		rawir.duration);
205 	ir_raw_event_store(ir->rc, &rawir);
206 
207 	ir_raw_event_handle(ir->rc);
208 
209 	return 1;
210 }
211 
212 /*
213  * Generic IR code
214  */
215 
216 static void au0828_rc_work(struct work_struct *work)
217 {
218 	struct au0828_rc *ir = container_of(work, struct au0828_rc, work.work);
219 	int rc;
220 
221 	rc = ir->get_key_i2c(ir);
222 	if (rc < 0)
223 		pr_info("Error while getting RC scancode\n");
224 
225 	schedule_delayed_work(&ir->work, msecs_to_jiffies(ir->polling));
226 }
227 
228 static int au0828_rc_start(struct rc_dev *rc)
229 {
230 	struct au0828_rc *ir = rc->priv;
231 
232 	INIT_DELAYED_WORK(&ir->work, au0828_rc_work);
233 
234 	/* Enable IR */
235 	au8522_rc_set(ir, 0xe0, 1 << 4);
236 
237 	schedule_delayed_work(&ir->work, msecs_to_jiffies(ir->polling));
238 
239 	return 0;
240 }
241 
242 static void au0828_rc_stop(struct rc_dev *rc)
243 {
244 	struct au0828_rc *ir = rc->priv;
245 
246 	/* Disable IR */
247 	au8522_rc_clear(ir, 0xe0, 1 << 4);
248 
249 	cancel_delayed_work_sync(&ir->work);
250 }
251 
252 static int au0828_probe_i2c_ir(struct au0828_dev *dev)
253 {
254 	int i = 0;
255 	const unsigned short addr_list[] = {
256 		 0x47, I2C_CLIENT_END
257 	};
258 
259 	while (addr_list[i] != I2C_CLIENT_END) {
260 		if (i2c_probe_func_quick_read(dev->i2c_client.adapter,
261 					      addr_list[i]) == 1)
262 			return addr_list[i];
263 		i++;
264 	}
265 
266 	return -ENODEV;
267 }
268 
269 int au0828_rc_register(struct au0828_dev *dev)
270 {
271 	struct au0828_rc *ir;
272 	struct rc_dev *rc;
273 	int err = -ENOMEM;
274 	u16 i2c_rc_dev_addr = 0;
275 
276 	if (!dev->board.has_ir_i2c)
277 		return 0;
278 
279 	i2c_rc_dev_addr = au0828_probe_i2c_ir(dev);
280 	if (!i2c_rc_dev_addr)
281 		return -ENODEV;
282 
283 	ir = kzalloc(sizeof(*ir), GFP_KERNEL);
284 	rc = rc_allocate_device();
285 	if (!ir || !rc)
286 		goto error;
287 
288 	/* record handles to ourself */
289 	ir->dev = dev;
290 	dev->ir = ir;
291 	ir->rc = rc;
292 
293 	rc->priv = ir;
294 	rc->open = au0828_rc_start;
295 	rc->close = au0828_rc_stop;
296 
297 	if (dev->board.has_ir_i2c) {	/* external i2c device */
298 		switch (dev->boardnr) {
299 		case AU0828_BOARD_HAUPPAUGE_HVR950Q:
300 			rc->map_name = RC_MAP_HAUPPAUGE;
301 			ir->get_key_i2c = au0828_get_key_au8522;
302 			break;
303 		default:
304 			err = -ENODEV;
305 			goto error;
306 		}
307 
308 		ir->i2c_dev_addr = i2c_rc_dev_addr;
309 	}
310 
311 	/* This is how often we ask the chip for IR information */
312 	ir->polling = 100; /* ms */
313 
314 	/* init input device */
315 	snprintf(ir->name, sizeof(ir->name), "au0828 IR (%s)",
316 		 dev->board.name);
317 
318 	usb_make_path(dev->usbdev, ir->phys, sizeof(ir->phys));
319 	strlcat(ir->phys, "/input0", sizeof(ir->phys));
320 
321 	rc->input_name = ir->name;
322 	rc->input_phys = ir->phys;
323 	rc->input_id.bustype = BUS_USB;
324 	rc->input_id.version = 1;
325 	rc->input_id.vendor = le16_to_cpu(dev->usbdev->descriptor.idVendor);
326 	rc->input_id.product = le16_to_cpu(dev->usbdev->descriptor.idProduct);
327 	rc->dev.parent = &dev->usbdev->dev;
328 	rc->driver_name = "au0828-input";
329 	rc->driver_type = RC_DRIVER_IR_RAW;
330 	rc->allowed_protocols = RC_BIT_NEC | RC_BIT_RC5;
331 
332 	/* all done */
333 	err = rc_register_device(rc);
334 	if (err)
335 		goto error;
336 
337 	pr_info("Remote controller %s initalized\n", ir->name);
338 
339 	return 0;
340 
341 error:
342 	dev->ir = NULL;
343 	rc_free_device(rc);
344 	kfree(ir);
345 	return err;
346 }
347 
348 void au0828_rc_unregister(struct au0828_dev *dev)
349 {
350 	struct au0828_rc *ir = dev->ir;
351 
352 	/* skip detach on non attached boards */
353 	if (!ir)
354 		return;
355 
356 	if (ir->rc)
357 		rc_unregister_device(ir->rc);
358 
359 	/* done */
360 	kfree(ir);
361 	dev->ir = NULL;
362 }
363 
364 int au0828_rc_suspend(struct au0828_dev *dev)
365 {
366 	struct au0828_rc *ir = dev->ir;
367 
368 	if (!ir)
369 		return 0;
370 
371 	cancel_delayed_work_sync(&ir->work);
372 
373 	return 0;
374 }
375 
376 int au0828_rc_resume(struct au0828_dev *dev)
377 {
378 	struct au0828_rc *ir = dev->ir;
379 
380 	if (!ir)
381 		return 0;
382 
383 	schedule_delayed_work(&ir->work, msecs_to_jiffies(ir->polling));
384 
385 	return 0;
386 }
387