1 // SPDX-License-Identifier: GPL-2.0+
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 #include "au0828.h"
10
11 #include <linux/module.h>
12 #include <linux/init.h>
13 #include <linux/delay.h>
14 #include <linux/interrupt.h>
15 #include <linux/usb.h>
16 #include <linux/slab.h>
17 #include <media/rc-core.h>
18
19 static int disable_ir;
20 module_param(disable_ir, int, 0444);
21 MODULE_PARM_DESC(disable_ir, "disable infrared remote support");
22
23 struct au0828_rc {
24 struct au0828_dev *dev;
25 struct rc_dev *rc;
26 char name[32];
27 char phys[32];
28
29 /* poll decoder */
30 int polling;
31 struct delayed_work work;
32
33 /* i2c slave address of external device (if used) */
34 u16 i2c_dev_addr;
35
36 int (*get_key_i2c)(struct au0828_rc *ir);
37 };
38
39 /*
40 * AU8522 has a builtin IR receiver. Add functions to get IR from it
41 */
42
au8522_rc_write(struct au0828_rc * ir,u16 reg,u8 data)43 static int au8522_rc_write(struct au0828_rc *ir, u16 reg, u8 data)
44 {
45 int rc;
46 char buf[] = { (reg >> 8) | 0x80, reg & 0xff, data };
47 struct i2c_msg msg = { .addr = ir->i2c_dev_addr, .flags = 0,
48 .buf = buf, .len = sizeof(buf) };
49
50 rc = i2c_transfer(ir->dev->i2c_client.adapter, &msg, 1);
51
52 if (rc < 0)
53 return rc;
54
55 return (rc == 1) ? 0 : -EIO;
56 }
57
au8522_rc_read(struct au0828_rc * ir,u16 reg,int val,char * buf,int size)58 static int au8522_rc_read(struct au0828_rc *ir, u16 reg, int val,
59 char *buf, int size)
60 {
61 int rc;
62 char obuf[3];
63 struct i2c_msg msg[2] = { { .addr = ir->i2c_dev_addr, .flags = 0,
64 .buf = obuf, .len = 2 },
65 { .addr = ir->i2c_dev_addr, .flags = I2C_M_RD,
66 .buf = buf, .len = size } };
67
68 obuf[0] = 0x40 | reg >> 8;
69 obuf[1] = reg & 0xff;
70 if (val >= 0) {
71 obuf[2] = val;
72 msg[0].len++;
73 }
74
75 rc = i2c_transfer(ir->dev->i2c_client.adapter, msg, 2);
76
77 if (rc < 0)
78 return rc;
79
80 return (rc == 2) ? 0 : -EIO;
81 }
82
au8522_rc_andor(struct au0828_rc * ir,u16 reg,u8 mask,u8 value)83 static int au8522_rc_andor(struct au0828_rc *ir, u16 reg, u8 mask, u8 value)
84 {
85 int rc;
86 char buf, oldbuf;
87
88 rc = au8522_rc_read(ir, reg, -1, &buf, 1);
89 if (rc < 0)
90 return rc;
91
92 oldbuf = buf;
93 buf = (buf & ~mask) | (value & mask);
94
95 /* Nothing to do, just return */
96 if (buf == oldbuf)
97 return 0;
98
99 return au8522_rc_write(ir, reg, buf);
100 }
101
102 #define au8522_rc_set(ir, reg, bit) au8522_rc_andor(ir, (reg), (bit), (bit))
103 #define au8522_rc_clear(ir, reg, bit) au8522_rc_andor(ir, (reg), (bit), 0)
104
105 /* Remote Controller time units */
106
107 #define AU8522_UNIT 200 /* us */
108 #define NEC_START_SPACE (4500 / AU8522_UNIT)
109 #define NEC_START_PULSE (563 * 16)
110 #define RC5_START_SPACE (4 * AU8522_UNIT)
111 #define RC5_START_PULSE 889
112
au0828_get_key_au8522(struct au0828_rc * ir)113 static int au0828_get_key_au8522(struct au0828_rc *ir)
114 {
115 unsigned char buf[40];
116 struct ir_raw_event rawir = {};
117 int i, j, rc;
118 int prv_bit, bit, width;
119 bool first = true;
120
121 /* do nothing if device is disconnected */
122 if (test_bit(DEV_DISCONNECTED, &ir->dev->dev_state))
123 return 0;
124
125 /* Check IR int */
126 rc = au8522_rc_read(ir, 0xe1, -1, buf, 1);
127 if (rc < 0 || !(buf[0] & (1 << 4))) {
128 /* Be sure that IR is enabled */
129 au8522_rc_set(ir, 0xe0, 1 << 4);
130 return 0;
131 }
132
133 /* Something arrived. Get the data */
134 rc = au8522_rc_read(ir, 0xe3, 0x11, buf, sizeof(buf));
135
136
137 if (rc < 0)
138 return rc;
139
140 /* Disable IR */
141 au8522_rc_clear(ir, 0xe0, 1 << 4);
142
143 /* Enable IR */
144 au8522_rc_set(ir, 0xe0, 1 << 4);
145
146 dprintk(16, "RC data received: %*ph\n", 40, buf);
147
148 prv_bit = (buf[0] >> 7) & 0x01;
149 width = 0;
150 for (i = 0; i < sizeof(buf); i++) {
151 for (j = 7; j >= 0; j--) {
152 bit = (buf[i] >> j) & 0x01;
153 if (bit == prv_bit) {
154 width++;
155 continue;
156 }
157
158 /*
159 * Fix an au8522 bug: the first pulse event
160 * is lost. So, we need to fake it, based on the
161 * protocol. That means that not all raw decoders
162 * will work, as we need to add a hack for each
163 * protocol, based on the first space.
164 * So, we only support RC5 and NEC.
165 */
166
167 if (first) {
168 first = false;
169
170 rawir.pulse = true;
171 if (width > NEC_START_SPACE - 2 &&
172 width < NEC_START_SPACE + 2) {
173 /* NEC protocol */
174 rawir.duration = NEC_START_PULSE;
175 dprintk(16, "Storing NEC start %s with duration %d",
176 rawir.pulse ? "pulse" : "space",
177 rawir.duration);
178 } else {
179 /* RC5 protocol */
180 rawir.duration = RC5_START_PULSE;
181 dprintk(16, "Storing RC5 start %s with duration %d",
182 rawir.pulse ? "pulse" : "space",
183 rawir.duration);
184 }
185 ir_raw_event_store(ir->rc, &rawir);
186 }
187
188 rawir.pulse = prv_bit ? false : true;
189 rawir.duration = AU8522_UNIT * width;
190 dprintk(16, "Storing %s with duration %d",
191 rawir.pulse ? "pulse" : "space",
192 rawir.duration);
193 ir_raw_event_store(ir->rc, &rawir);
194
195 width = 1;
196 prv_bit = bit;
197 }
198 }
199
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
au0828_rc_work(struct work_struct * work)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
au0828_rc_start(struct rc_dev * rc)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
au0828_rc_stop(struct rc_dev * rc)242 static void au0828_rc_stop(struct rc_dev *rc)
243 {
244 struct au0828_rc *ir = rc->priv;
245
246 cancel_delayed_work_sync(&ir->work);
247
248 /* do nothing if device is disconnected */
249 if (!test_bit(DEV_DISCONNECTED, &ir->dev->dev_state)) {
250 /* Disable IR */
251 au8522_rc_clear(ir, 0xe0, 1 << 4);
252 }
253 }
254
au0828_probe_i2c_ir(struct au0828_dev * dev)255 static int au0828_probe_i2c_ir(struct au0828_dev *dev)
256 {
257 int i = 0;
258 static const unsigned short addr_list[] = {
259 0x47, I2C_CLIENT_END
260 };
261
262 while (addr_list[i] != I2C_CLIENT_END) {
263 if (i2c_probe_func_quick_read(dev->i2c_client.adapter,
264 addr_list[i]) == 1)
265 return addr_list[i];
266 i++;
267 }
268
269 return -ENODEV;
270 }
271
au0828_rc_register(struct au0828_dev * dev)272 int au0828_rc_register(struct au0828_dev *dev)
273 {
274 struct au0828_rc *ir;
275 struct rc_dev *rc;
276 int err = -ENOMEM;
277 u16 i2c_rc_dev_addr = 0;
278
279 if (!dev->board.has_ir_i2c || disable_ir)
280 return 0;
281
282 i2c_rc_dev_addr = au0828_probe_i2c_ir(dev);
283 if (!i2c_rc_dev_addr)
284 return -ENODEV;
285
286 ir = kzalloc(sizeof(*ir), GFP_KERNEL);
287 rc = rc_allocate_device(RC_DRIVER_IR_RAW);
288 if (!ir || !rc)
289 goto error;
290
291 /* record handles to ourself */
292 ir->dev = dev;
293 dev->ir = ir;
294 ir->rc = rc;
295
296 rc->priv = ir;
297 rc->open = au0828_rc_start;
298 rc->close = au0828_rc_stop;
299
300 if (dev->board.has_ir_i2c) { /* external i2c device */
301 switch (dev->boardnr) {
302 case AU0828_BOARD_HAUPPAUGE_HVR950Q:
303 rc->map_name = RC_MAP_HAUPPAUGE;
304 ir->get_key_i2c = au0828_get_key_au8522;
305 break;
306 default:
307 err = -ENODEV;
308 goto error;
309 }
310
311 ir->i2c_dev_addr = i2c_rc_dev_addr;
312 }
313
314 /* This is how often we ask the chip for IR information */
315 ir->polling = 100; /* ms */
316
317 /* init input device */
318 snprintf(ir->name, sizeof(ir->name), "au0828 IR (%s)",
319 dev->board.name);
320
321 usb_make_path(dev->usbdev, ir->phys, sizeof(ir->phys));
322 strlcat(ir->phys, "/input0", sizeof(ir->phys));
323
324 rc->device_name = ir->name;
325 rc->input_phys = ir->phys;
326 rc->input_id.bustype = BUS_USB;
327 rc->input_id.version = 1;
328 rc->input_id.vendor = le16_to_cpu(dev->usbdev->descriptor.idVendor);
329 rc->input_id.product = le16_to_cpu(dev->usbdev->descriptor.idProduct);
330 rc->dev.parent = &dev->usbdev->dev;
331 rc->driver_name = "au0828-input";
332 rc->allowed_protocols = RC_PROTO_BIT_NEC | RC_PROTO_BIT_NECX |
333 RC_PROTO_BIT_NEC32 | RC_PROTO_BIT_RC5;
334
335 /* all done */
336 err = rc_register_device(rc);
337 if (err)
338 goto error;
339
340 pr_info("Remote controller %s initialized\n", ir->name);
341
342 return 0;
343
344 error:
345 dev->ir = NULL;
346 rc_free_device(rc);
347 kfree(ir);
348 return err;
349 }
350
au0828_rc_unregister(struct au0828_dev * dev)351 void au0828_rc_unregister(struct au0828_dev *dev)
352 {
353 struct au0828_rc *ir = dev->ir;
354
355 /* skip detach on non attached boards */
356 if (!ir)
357 return;
358
359 rc_unregister_device(ir->rc);
360
361 /* done */
362 kfree(ir);
363 dev->ir = NULL;
364 }
365
au0828_rc_suspend(struct au0828_dev * dev)366 int au0828_rc_suspend(struct au0828_dev *dev)
367 {
368 struct au0828_rc *ir = dev->ir;
369
370 if (!ir)
371 return 0;
372
373 pr_info("Stopping RC\n");
374
375 cancel_delayed_work_sync(&ir->work);
376
377 /* Disable IR */
378 au8522_rc_clear(ir, 0xe0, 1 << 4);
379
380 return 0;
381 }
382
au0828_rc_resume(struct au0828_dev * dev)383 int au0828_rc_resume(struct au0828_dev *dev)
384 {
385 struct au0828_rc *ir = dev->ir;
386
387 if (!ir)
388 return 0;
389
390 pr_info("Restarting RC\n");
391
392 /* Enable IR */
393 au8522_rc_set(ir, 0xe0, 1 << 4);
394
395 schedule_delayed_work(&ir->work, msecs_to_jiffies(ir->polling));
396
397 return 0;
398 }
399