1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright 2013 Cisco Systems, Inc. and/or its affiliates.
4 * All rights reserved.
5 */
6
7 /* kernel includes */
8 #include <linux/kernel.h>
9 #include <linux/module.h>
10 #include <linux/usb.h>
11 #include <linux/init.h>
12 #include <linux/slab.h>
13 #include <linux/input.h>
14 #include <linux/mutex.h>
15 #include <linux/i2c.h>
16 /* V4l includes */
17 #include <linux/videodev2.h>
18 #include <media/v4l2-common.h>
19 #include <media/v4l2-device.h>
20 #include <media/v4l2-ioctl.h>
21 #include <media/v4l2-event.h>
22 #include <linux/platform_data/media/si4713.h>
23
24 #include "si4713.h"
25
26 /* driver and module definitions */
27 MODULE_AUTHOR("Dinesh Ram <dinesh.ram@cern.ch>");
28 MODULE_DESCRIPTION("Si4713 FM Transmitter USB driver");
29 MODULE_LICENSE("GPL v2");
30
31 /* The Device announces itself as Cygnal Integrated Products, Inc. */
32 #define USB_SI4713_VENDOR 0x10c4
33 #define USB_SI4713_PRODUCT 0x8244
34
35 #define BUFFER_LENGTH 64
36 #define USB_TIMEOUT 1000
37 #define USB_RESP_TIMEOUT 50000
38
39 /* USB Device ID List */
40 static const struct usb_device_id usb_si4713_usb_device_table[] = {
41 {USB_DEVICE_AND_INTERFACE_INFO(USB_SI4713_VENDOR, USB_SI4713_PRODUCT,
42 USB_CLASS_HID, 0, 0) },
43 { } /* Terminating entry */
44 };
45
46 MODULE_DEVICE_TABLE(usb, usb_si4713_usb_device_table);
47
48 struct si4713_usb_device {
49 struct usb_device *usbdev;
50 struct usb_interface *intf;
51 struct video_device vdev;
52 struct v4l2_device v4l2_dev;
53 struct v4l2_subdev *v4l2_subdev;
54 struct mutex lock;
55 struct i2c_adapter i2c_adapter;
56
57 u8 *buffer;
58 };
59
to_si4713_dev(struct v4l2_device * v4l2_dev)60 static inline struct si4713_usb_device *to_si4713_dev(struct v4l2_device *v4l2_dev)
61 {
62 return container_of(v4l2_dev, struct si4713_usb_device, v4l2_dev);
63 }
64
vidioc_querycap(struct file * file,void * priv,struct v4l2_capability * v)65 static int vidioc_querycap(struct file *file, void *priv,
66 struct v4l2_capability *v)
67 {
68 struct si4713_usb_device *radio = video_drvdata(file);
69
70 strscpy(v->driver, "radio-usb-si4713", sizeof(v->driver));
71 strscpy(v->card, "Si4713 FM Transmitter", sizeof(v->card));
72 usb_make_path(radio->usbdev, v->bus_info, sizeof(v->bus_info));
73 return 0;
74 }
75
vidioc_g_modulator(struct file * file,void * priv,struct v4l2_modulator * vm)76 static int vidioc_g_modulator(struct file *file, void *priv,
77 struct v4l2_modulator *vm)
78 {
79 struct si4713_usb_device *radio = video_drvdata(file);
80
81 return v4l2_subdev_call(radio->v4l2_subdev, tuner, g_modulator, vm);
82 }
83
vidioc_s_modulator(struct file * file,void * priv,const struct v4l2_modulator * vm)84 static int vidioc_s_modulator(struct file *file, void *priv,
85 const struct v4l2_modulator *vm)
86 {
87 struct si4713_usb_device *radio = video_drvdata(file);
88
89 return v4l2_subdev_call(radio->v4l2_subdev, tuner, s_modulator, vm);
90 }
91
vidioc_s_frequency(struct file * file,void * priv,const struct v4l2_frequency * vf)92 static int vidioc_s_frequency(struct file *file, void *priv,
93 const struct v4l2_frequency *vf)
94 {
95 struct si4713_usb_device *radio = video_drvdata(file);
96
97 return v4l2_subdev_call(radio->v4l2_subdev, tuner, s_frequency, vf);
98 }
99
vidioc_g_frequency(struct file * file,void * priv,struct v4l2_frequency * vf)100 static int vidioc_g_frequency(struct file *file, void *priv,
101 struct v4l2_frequency *vf)
102 {
103 struct si4713_usb_device *radio = video_drvdata(file);
104
105 return v4l2_subdev_call(radio->v4l2_subdev, tuner, g_frequency, vf);
106 }
107
108 static const struct v4l2_ioctl_ops usb_si4713_ioctl_ops = {
109 .vidioc_querycap = vidioc_querycap,
110 .vidioc_g_modulator = vidioc_g_modulator,
111 .vidioc_s_modulator = vidioc_s_modulator,
112 .vidioc_g_frequency = vidioc_g_frequency,
113 .vidioc_s_frequency = vidioc_s_frequency,
114 .vidioc_log_status = v4l2_ctrl_log_status,
115 .vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
116 .vidioc_unsubscribe_event = v4l2_event_unsubscribe,
117 };
118
119 /* File system interface */
120 static const struct v4l2_file_operations usb_si4713_fops = {
121 .owner = THIS_MODULE,
122 .open = v4l2_fh_open,
123 .release = v4l2_fh_release,
124 .poll = v4l2_ctrl_poll,
125 .unlocked_ioctl = video_ioctl2,
126 };
127
usb_si4713_video_device_release(struct v4l2_device * v4l2_dev)128 static void usb_si4713_video_device_release(struct v4l2_device *v4l2_dev)
129 {
130 struct si4713_usb_device *radio = to_si4713_dev(v4l2_dev);
131 struct i2c_adapter *adapter = &radio->i2c_adapter;
132
133 i2c_del_adapter(adapter);
134 v4l2_device_unregister(&radio->v4l2_dev);
135 kfree(radio->buffer);
136 kfree(radio);
137 }
138
139 /*
140 * This command sequence emulates the behaviour of the Windows driver.
141 * The structure of these commands was determined by sniffing the
142 * usb traffic of the device during startup.
143 * Most likely, these commands make some queries to the device.
144 * Commands are sent to enquire parameters like the bus mode,
145 * component revision, boot mode, the device serial number etc.
146 *
147 * These commands are necessary to be sent in this order during startup.
148 * The device fails to powerup if these commands are not sent.
149 *
150 * The complete list of startup commands is given in the start_seq table below.
151 */
si4713_send_startup_command(struct si4713_usb_device * radio)152 static int si4713_send_startup_command(struct si4713_usb_device *radio)
153 {
154 unsigned long until_jiffies = jiffies + usecs_to_jiffies(USB_RESP_TIMEOUT) + 1;
155 u8 *buffer = radio->buffer;
156 int retval;
157
158 /* send the command */
159 retval = usb_control_msg(radio->usbdev, usb_sndctrlpipe(radio->usbdev, 0),
160 0x09, 0x21, 0x033f, 0, radio->buffer,
161 BUFFER_LENGTH, USB_TIMEOUT);
162 if (retval < 0)
163 return retval;
164
165 for (;;) {
166 /* receive the response */
167 retval = usb_control_msg(radio->usbdev, usb_rcvctrlpipe(radio->usbdev, 0),
168 0x01, 0xa1, 0x033f, 0, radio->buffer,
169 BUFFER_LENGTH, USB_TIMEOUT);
170 if (retval < 0)
171 return retval;
172 if (!radio->buffer[1]) {
173 /* USB traffic sniffing showed that some commands require
174 * additional checks. */
175 switch (buffer[1]) {
176 case 0x32:
177 if (radio->buffer[2] == 0)
178 return 0;
179 break;
180 case 0x14:
181 case 0x12:
182 if (radio->buffer[2] & SI4713_CTS)
183 return 0;
184 break;
185 case 0x06:
186 if ((radio->buffer[2] & SI4713_CTS) && radio->buffer[9] == 0x08)
187 return 0;
188 break;
189 default:
190 return 0;
191 }
192 }
193 if (time_is_before_jiffies(until_jiffies))
194 return -EIO;
195 msleep(3);
196 }
197
198 return retval;
199 }
200
201 struct si4713_start_seq_table {
202 int len;
203 u8 payload[8];
204 };
205
206 /*
207 * Some of the startup commands that could be recognized are :
208 * (0x03): Get serial number of the board (Response : CB000-00-00)
209 * (0x06, 0x03, 0x03, 0x08, 0x01, 0x0f) : Get Component revision
210 */
211 static const struct si4713_start_seq_table start_seq[] = {
212
213 { 1, { 0x03 } },
214 { 2, { 0x32, 0x7f } },
215 { 6, { 0x06, 0x03, 0x03, 0x08, 0x01, 0x0f } },
216 { 2, { 0x14, 0x02 } },
217 { 2, { 0x09, 0x90 } },
218 { 3, { 0x08, 0x90, 0xfa } },
219 { 2, { 0x36, 0x01 } },
220 { 2, { 0x05, 0x03 } },
221 { 7, { 0x06, 0x00, 0x06, 0x0e, 0x01, 0x0f, 0x05 } },
222 { 1, { 0x12 } },
223 /* Commands that are sent after pressing the 'Initialize'
224 button in the windows application */
225 { 1, { 0x03 } },
226 { 1, { 0x01 } },
227 { 2, { 0x09, 0x90 } },
228 { 3, { 0x08, 0x90, 0xfa } },
229 { 1, { 0x34 } },
230 { 2, { 0x35, 0x01 } },
231 { 2, { 0x36, 0x01 } },
232 { 2, { 0x30, 0x09 } },
233 { 4, { 0x30, 0x06, 0x00, 0xe2 } },
234 { 3, { 0x31, 0x01, 0x30 } },
235 { 3, { 0x31, 0x04, 0x09 } },
236 { 2, { 0x05, 0x02 } },
237 { 6, { 0x06, 0x03, 0x03, 0x08, 0x01, 0x0f } },
238 };
239
si4713_start_seq(struct si4713_usb_device * radio)240 static int si4713_start_seq(struct si4713_usb_device *radio)
241 {
242 int retval = 0;
243 int i;
244
245 radio->buffer[0] = 0x3f;
246
247 for (i = 0; i < ARRAY_SIZE(start_seq); i++) {
248 int len = start_seq[i].len;
249 const u8 *payload = start_seq[i].payload;
250
251 memcpy(radio->buffer + 1, payload, len);
252 memset(radio->buffer + len + 1, 0, BUFFER_LENGTH - 1 - len);
253 retval = si4713_send_startup_command(radio);
254 }
255
256 return retval;
257 }
258
259 static struct i2c_board_info si4713_board_info = {
260 I2C_BOARD_INFO("si4713", SI4713_I2C_ADDR_BUSEN_HIGH),
261 };
262
263 struct si4713_command_table {
264 int command_id;
265 u8 payload[8];
266 };
267
268 /*
269 * Structure of a command :
270 * Byte 1 : 0x3f (always)
271 * Byte 2 : 0x06 (send a command)
272 * Byte 3 : Unknown
273 * Byte 4 : Number of arguments + 1 (for the command byte)
274 * Byte 5 : Number of response bytes
275 */
276 static struct si4713_command_table command_table[] = {
277
278 { SI4713_CMD_POWER_UP, { 0x00, SI4713_PWUP_NARGS + 1, SI4713_PWUP_NRESP} },
279 { SI4713_CMD_GET_REV, { 0x03, 0x01, SI4713_GETREV_NRESP } },
280 { SI4713_CMD_POWER_DOWN, { 0x00, 0x01, SI4713_PWDN_NRESP} },
281 { SI4713_CMD_SET_PROPERTY, { 0x00, SI4713_SET_PROP_NARGS + 1, SI4713_SET_PROP_NRESP } },
282 { SI4713_CMD_GET_PROPERTY, { 0x00, SI4713_GET_PROP_NARGS + 1, SI4713_GET_PROP_NRESP } },
283 { SI4713_CMD_TX_TUNE_FREQ, { 0x03, SI4713_TXFREQ_NARGS + 1, SI4713_TXFREQ_NRESP } },
284 { SI4713_CMD_TX_TUNE_POWER, { 0x03, SI4713_TXPWR_NARGS + 1, SI4713_TXPWR_NRESP } },
285 { SI4713_CMD_TX_TUNE_MEASURE, { 0x03, SI4713_TXMEA_NARGS + 1, SI4713_TXMEA_NRESP } },
286 { SI4713_CMD_TX_TUNE_STATUS, { 0x00, SI4713_TXSTATUS_NARGS + 1, SI4713_TXSTATUS_NRESP } },
287 { SI4713_CMD_TX_ASQ_STATUS, { 0x03, SI4713_ASQSTATUS_NARGS + 1, SI4713_ASQSTATUS_NRESP } },
288 { SI4713_CMD_GET_INT_STATUS, { 0x03, 0x01, SI4713_GET_STATUS_NRESP } },
289 { SI4713_CMD_TX_RDS_BUFF, { 0x03, SI4713_RDSBUFF_NARGS + 1, SI4713_RDSBUFF_NRESP } },
290 { SI4713_CMD_TX_RDS_PS, { 0x00, SI4713_RDSPS_NARGS + 1, SI4713_RDSPS_NRESP } },
291 };
292
send_command(struct si4713_usb_device * radio,u8 * payload,char * data,int len)293 static int send_command(struct si4713_usb_device *radio, u8 *payload, char *data, int len)
294 {
295 int retval;
296
297 radio->buffer[0] = 0x3f;
298 radio->buffer[1] = 0x06;
299
300 memcpy(radio->buffer + 2, payload, 3);
301 memcpy(radio->buffer + 5, data, len);
302 memset(radio->buffer + 5 + len, 0, BUFFER_LENGTH - 5 - len);
303
304 /* send the command */
305 retval = usb_control_msg(radio->usbdev, usb_sndctrlpipe(radio->usbdev, 0),
306 0x09, 0x21, 0x033f, 0, radio->buffer,
307 BUFFER_LENGTH, USB_TIMEOUT);
308
309 return retval < 0 ? retval : 0;
310 }
311
si4713_i2c_read(struct si4713_usb_device * radio,char * data,int len)312 static int si4713_i2c_read(struct si4713_usb_device *radio, char *data, int len)
313 {
314 unsigned long until_jiffies = jiffies + usecs_to_jiffies(USB_RESP_TIMEOUT) + 1;
315 int retval;
316
317 /* receive the response */
318 for (;;) {
319 retval = usb_control_msg(radio->usbdev,
320 usb_rcvctrlpipe(radio->usbdev, 0),
321 0x01, 0xa1, 0x033f, 0, radio->buffer,
322 BUFFER_LENGTH, USB_TIMEOUT);
323 if (retval < 0)
324 return retval;
325
326 /*
327 * Check that we get a valid reply back (buffer[1] == 0) and
328 * that CTS is set before returning, otherwise we wait and try
329 * again. The i2c driver also does the CTS check, but the timeouts
330 * used there are much too small for this USB driver, so we wait
331 * for it here.
332 */
333 if (radio->buffer[1] == 0 && (radio->buffer[2] & SI4713_CTS)) {
334 memcpy(data, radio->buffer + 2, len);
335 return 0;
336 }
337 if (time_is_before_jiffies(until_jiffies)) {
338 /* Zero the status value, ensuring CTS isn't set */
339 data[0] = 0;
340 return 0;
341 }
342 msleep(3);
343 }
344 }
345
si4713_i2c_write(struct si4713_usb_device * radio,char * data,int len)346 static int si4713_i2c_write(struct si4713_usb_device *radio, char *data, int len)
347 {
348 int retval = -EINVAL;
349 int i;
350
351 if (len > BUFFER_LENGTH - 5)
352 return -EINVAL;
353
354 for (i = 0; i < ARRAY_SIZE(command_table); i++) {
355 if (data[0] == command_table[i].command_id)
356 retval = send_command(radio, command_table[i].payload,
357 data, len);
358 }
359
360 return retval < 0 ? retval : 0;
361 }
362
si4713_transfer(struct i2c_adapter * i2c_adapter,struct i2c_msg * msgs,int num)363 static int si4713_transfer(struct i2c_adapter *i2c_adapter,
364 struct i2c_msg *msgs, int num)
365 {
366 struct si4713_usb_device *radio = i2c_get_adapdata(i2c_adapter);
367 int retval = -EINVAL;
368 int i;
369
370 for (i = 0; i < num; i++) {
371 if (msgs[i].flags & I2C_M_RD)
372 retval = si4713_i2c_read(radio, msgs[i].buf, msgs[i].len);
373 else
374 retval = si4713_i2c_write(radio, msgs[i].buf, msgs[i].len);
375 if (retval)
376 break;
377 }
378
379 return retval ? retval : num;
380 }
381
si4713_functionality(struct i2c_adapter * adapter)382 static u32 si4713_functionality(struct i2c_adapter *adapter)
383 {
384 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
385 }
386
387 static const struct i2c_algorithm si4713_algo = {
388 .master_xfer = si4713_transfer,
389 .functionality = si4713_functionality,
390 };
391
392 /* This name value shows up in the sysfs filename associated
393 with this I2C adapter */
394 static const struct i2c_adapter si4713_i2c_adapter_template = {
395 .name = "si4713-i2c",
396 .owner = THIS_MODULE,
397 .algo = &si4713_algo,
398 };
399
si4713_register_i2c_adapter(struct si4713_usb_device * radio)400 static int si4713_register_i2c_adapter(struct si4713_usb_device *radio)
401 {
402 radio->i2c_adapter = si4713_i2c_adapter_template;
403 /* set up sysfs linkage to our parent device */
404 radio->i2c_adapter.dev.parent = &radio->usbdev->dev;
405 i2c_set_adapdata(&radio->i2c_adapter, radio);
406
407 return i2c_add_adapter(&radio->i2c_adapter);
408 }
409
410 /* check if the device is present and register with v4l and usb if it is */
usb_si4713_probe(struct usb_interface * intf,const struct usb_device_id * id)411 static int usb_si4713_probe(struct usb_interface *intf,
412 const struct usb_device_id *id)
413 {
414 struct si4713_usb_device *radio;
415 struct i2c_adapter *adapter;
416 struct v4l2_subdev *sd;
417 int retval;
418
419 dev_info(&intf->dev, "Si4713 development board discovered: (%04X:%04X)\n",
420 id->idVendor, id->idProduct);
421
422 /* Initialize local device structure */
423 radio = kzalloc(sizeof(struct si4713_usb_device), GFP_KERNEL);
424 if (radio)
425 radio->buffer = kmalloc(BUFFER_LENGTH, GFP_KERNEL);
426
427 if (!radio || !radio->buffer) {
428 dev_err(&intf->dev, "kmalloc for si4713_usb_device failed\n");
429 kfree(radio);
430 return -ENOMEM;
431 }
432
433 mutex_init(&radio->lock);
434
435 radio->usbdev = interface_to_usbdev(intf);
436 radio->intf = intf;
437 usb_set_intfdata(intf, &radio->v4l2_dev);
438
439 retval = si4713_start_seq(radio);
440 if (retval < 0)
441 goto err_v4l2;
442
443 retval = v4l2_device_register(&intf->dev, &radio->v4l2_dev);
444 if (retval < 0) {
445 dev_err(&intf->dev, "couldn't register v4l2_device\n");
446 goto err_v4l2;
447 }
448
449 retval = si4713_register_i2c_adapter(radio);
450 if (retval < 0) {
451 dev_err(&intf->dev, "could not register i2c device\n");
452 goto err_i2cdev;
453 }
454
455 adapter = &radio->i2c_adapter;
456 sd = v4l2_i2c_new_subdev_board(&radio->v4l2_dev, adapter,
457 &si4713_board_info, NULL);
458 radio->v4l2_subdev = sd;
459 if (!sd) {
460 dev_err(&intf->dev, "cannot get v4l2 subdevice\n");
461 retval = -ENODEV;
462 goto del_adapter;
463 }
464
465 radio->vdev.ctrl_handler = sd->ctrl_handler;
466 radio->v4l2_dev.release = usb_si4713_video_device_release;
467 strscpy(radio->vdev.name, radio->v4l2_dev.name,
468 sizeof(radio->vdev.name));
469 radio->vdev.v4l2_dev = &radio->v4l2_dev;
470 radio->vdev.fops = &usb_si4713_fops;
471 radio->vdev.ioctl_ops = &usb_si4713_ioctl_ops;
472 radio->vdev.lock = &radio->lock;
473 radio->vdev.release = video_device_release_empty;
474 radio->vdev.vfl_dir = VFL_DIR_TX;
475 radio->vdev.device_caps = V4L2_CAP_MODULATOR | V4L2_CAP_RDS_OUTPUT;
476
477 video_set_drvdata(&radio->vdev, radio);
478
479 retval = video_register_device(&radio->vdev, VFL_TYPE_RADIO, -1);
480 if (retval < 0) {
481 dev_err(&intf->dev, "could not register video device\n");
482 goto del_adapter;
483 }
484
485 dev_info(&intf->dev, "V4L2 device registered as %s\n",
486 video_device_node_name(&radio->vdev));
487
488 return 0;
489
490 del_adapter:
491 i2c_del_adapter(adapter);
492 err_i2cdev:
493 v4l2_device_unregister(&radio->v4l2_dev);
494 err_v4l2:
495 kfree(radio->buffer);
496 kfree(radio);
497 return retval;
498 }
499
usb_si4713_disconnect(struct usb_interface * intf)500 static void usb_si4713_disconnect(struct usb_interface *intf)
501 {
502 struct si4713_usb_device *radio = to_si4713_dev(usb_get_intfdata(intf));
503
504 dev_info(&intf->dev, "Si4713 development board now disconnected\n");
505
506 mutex_lock(&radio->lock);
507 usb_set_intfdata(intf, NULL);
508 video_unregister_device(&radio->vdev);
509 v4l2_device_disconnect(&radio->v4l2_dev);
510 mutex_unlock(&radio->lock);
511 v4l2_device_put(&radio->v4l2_dev);
512 }
513
514 /* USB subsystem interface */
515 static struct usb_driver usb_si4713_driver = {
516 .name = "radio-usb-si4713",
517 .probe = usb_si4713_probe,
518 .disconnect = usb_si4713_disconnect,
519 .id_table = usb_si4713_usb_device_table,
520 };
521
522 module_usb_driver(usb_si4713_driver);
523