1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * drivers/media/radio/si470x/radio-si470x-i2c.c
5 * I2C driver for radios with Silicon Labs Si470x FM Radio Receivers
7 * Copyright (c) 2009 Samsung Electronics Co.Ltd
8 * Author: Joonyoung Shim <jy0922.shim@samsung.com>
12 /* driver definitions */
13 #define DRIVER_AUTHOR "Joonyoung Shim <jy0922.shim@samsung.com>";
14 #define DRIVER_CARD "Silicon Labs Si470x FM Radio Receiver"
15 #define DRIVER_DESC "I2C radio driver for Si470x FM Radio Receivers"
16 #define DRIVER_VERSION "1.0.2"
19 #include <linux/i2c.h>
20 #include <linux/slab.h>
21 #include <linux/delay.h>
22 #include <linux/gpio/consumer.h>
23 #include <linux/interrupt.h>
25 #include "radio-si470x.h"
28 /* I2C Device ID List */
29 static const struct i2c_device_id si470x_i2c_id[] = {
32 /* Terminating entry */
35 MODULE_DEVICE_TABLE(i2c, si470x_i2c_id);
38 /**************************************************************************
40 **************************************************************************/
43 static int radio_nr = -1;
44 module_param(radio_nr, int, 0444);
45 MODULE_PARM_DESC(radio_nr, "Radio Nr");
47 /* RDS buffer blocks */
48 static unsigned int rds_buf = 100;
49 module_param(rds_buf, uint, 0444);
50 MODULE_PARM_DESC(rds_buf, "RDS buffer entries: *100*");
52 /* RDS maximum block errors */
53 static unsigned short max_rds_errors = 1;
54 /* 0 means 0 errors requiring correction */
55 /* 1 means 1-2 errors requiring correction (used by original USBRadio.exe) */
56 /* 2 means 3-5 errors requiring correction */
57 /* 3 means 6+ errors or errors in checkword, correction not possible */
58 module_param(max_rds_errors, ushort, 0644);
59 MODULE_PARM_DESC(max_rds_errors, "RDS maximum block errors: *1*");
63 /**************************************************************************
65 **************************************************************************/
67 /* Write starts with the upper byte of register 0x02 */
68 #define WRITE_REG_NUM 8
69 #define WRITE_INDEX(i) (i + 0x02)
71 /* Read starts with the upper byte of register 0x0a */
72 #define READ_REG_NUM RADIO_REGISTER_NUM
73 #define READ_INDEX(i) ((i + RADIO_REGISTER_NUM - 0x0a) % READ_REG_NUM)
77 /**************************************************************************
78 * General Driver Functions - REGISTERs
79 **************************************************************************/
82 * si470x_get_register - read register
84 static int si470x_get_register(struct si470x_device *radio, int regnr)
86 __be16 buf[READ_REG_NUM];
87 struct i2c_msg msgs[1] = {
89 .addr = radio->client->addr,
91 .len = sizeof(u16) * READ_REG_NUM,
96 if (i2c_transfer(radio->client->adapter, msgs, 1) != 1)
99 radio->registers[regnr] = __be16_to_cpu(buf[READ_INDEX(regnr)]);
106 * si470x_set_register - write register
108 static int si470x_set_register(struct si470x_device *radio, int regnr)
111 __be16 buf[WRITE_REG_NUM];
112 struct i2c_msg msgs[1] = {
114 .addr = radio->client->addr,
115 .len = sizeof(u16) * WRITE_REG_NUM,
120 for (i = 0; i < WRITE_REG_NUM; i++)
121 buf[i] = __cpu_to_be16(radio->registers[WRITE_INDEX(i)]);
123 if (i2c_transfer(radio->client->adapter, msgs, 1) != 1)
131 /**************************************************************************
132 * General Driver Functions - ENTIRE REGISTERS
133 **************************************************************************/
136 * si470x_get_all_registers - read entire registers
138 static int si470x_get_all_registers(struct si470x_device *radio)
141 __be16 buf[READ_REG_NUM];
142 struct i2c_msg msgs[1] = {
144 .addr = radio->client->addr,
146 .len = sizeof(u16) * READ_REG_NUM,
151 if (i2c_transfer(radio->client->adapter, msgs, 1) != 1)
154 for (i = 0; i < READ_REG_NUM; i++)
155 radio->registers[i] = __be16_to_cpu(buf[READ_INDEX(i)]);
162 /**************************************************************************
163 * File Operations Interface
164 **************************************************************************/
167 * si470x_fops_open - file open
169 static int si470x_fops_open(struct file *file)
171 struct si470x_device *radio = video_drvdata(file);
172 int retval = v4l2_fh_open(file);
177 if (v4l2_fh_is_singular_file(file)) {
179 retval = si470x_start(radio);
183 /* enable RDS / STC interrupt */
184 radio->registers[SYSCONFIG1] |= SYSCONFIG1_RDSIEN;
185 radio->registers[SYSCONFIG1] |= SYSCONFIG1_STCIEN;
186 radio->registers[SYSCONFIG1] &= ~SYSCONFIG1_GPIO2;
187 radio->registers[SYSCONFIG1] |= 0x1 << 2;
188 retval = si470x_set_register(radio, SYSCONFIG1);
193 v4l2_fh_release(file);
199 * si470x_fops_release - file release
201 static int si470x_fops_release(struct file *file)
203 struct si470x_device *radio = video_drvdata(file);
205 if (v4l2_fh_is_singular_file(file))
209 return v4l2_fh_release(file);
214 /**************************************************************************
215 * Video4Linux Interface
216 **************************************************************************/
219 * si470x_vidioc_querycap - query device capabilities
221 static int si470x_vidioc_querycap(struct file *file, void *priv,
222 struct v4l2_capability *capability)
224 strscpy(capability->driver, DRIVER_NAME, sizeof(capability->driver));
225 strscpy(capability->card, DRIVER_CARD, sizeof(capability->card));
231 /**************************************************************************
233 **************************************************************************/
236 * si470x_i2c_interrupt - interrupt handler
238 static irqreturn_t si470x_i2c_interrupt(int irq, void *dev_id)
240 struct si470x_device *radio = dev_id;
242 unsigned char blocknum;
243 unsigned short bler; /* rds block errors */
245 unsigned char tmpbuf[3];
248 /* check Seek/Tune Complete */
249 retval = si470x_get_register(radio, STATUSRSSI);
253 if (radio->registers[STATUSRSSI] & STATUSRSSI_STC)
254 complete(&radio->completion);
257 if ((radio->registers[SYSCONFIG1] & SYSCONFIG1_RDS) == 0)
260 /* Update RDS registers */
261 for (regnr = 1; regnr < RDS_REGISTER_NUM; regnr++) {
262 retval = si470x_get_register(radio, STATUSRSSI + regnr);
268 if ((radio->registers[STATUSRSSI] & STATUSRSSI_RDSR) == 0)
269 /* No RDS group ready, better luck next time */
272 for (blocknum = 0; blocknum < 4; blocknum++) {
275 bler = (radio->registers[STATUSRSSI] &
276 STATUSRSSI_BLERA) >> 9;
277 rds = radio->registers[RDSA];
280 bler = (radio->registers[READCHAN] &
281 READCHAN_BLERB) >> 14;
282 rds = radio->registers[RDSB];
285 bler = (radio->registers[READCHAN] &
286 READCHAN_BLERC) >> 12;
287 rds = radio->registers[RDSC];
290 bler = (radio->registers[READCHAN] &
291 READCHAN_BLERD) >> 10;
292 rds = radio->registers[RDSD];
296 /* Fill the V4L2 RDS buffer */
297 put_unaligned_le16(rds, &tmpbuf);
298 tmpbuf[2] = blocknum; /* offset name */
299 tmpbuf[2] |= blocknum << 3; /* received offset */
300 if (bler > max_rds_errors)
301 tmpbuf[2] |= 0x80; /* uncorrectable errors */
303 tmpbuf[2] |= 0x40; /* corrected error(s) */
305 /* copy RDS block to internal buffer */
306 memcpy(&radio->buffer[radio->wr_index], &tmpbuf, 3);
307 radio->wr_index += 3;
309 /* wrap write pointer */
310 if (radio->wr_index >= radio->buf_size)
313 /* check for overflow */
314 if (radio->wr_index == radio->rd_index) {
315 /* increment and wrap read pointer */
316 radio->rd_index += 3;
317 if (radio->rd_index >= radio->buf_size)
322 if (radio->wr_index != radio->rd_index)
323 wake_up_interruptible(&radio->read_queue);
331 * si470x_i2c_probe - probe for the device
333 static int si470x_i2c_probe(struct i2c_client *client,
334 const struct i2c_device_id *id)
336 struct si470x_device *radio;
338 unsigned char version_warning = 0;
340 /* private data allocation and initialization */
341 radio = devm_kzalloc(&client->dev, sizeof(*radio), GFP_KERNEL);
347 radio->client = client;
348 radio->band = 1; /* Default to 76 - 108 MHz */
349 mutex_init(&radio->lock);
350 init_completion(&radio->completion);
352 radio->get_register = si470x_get_register;
353 radio->set_register = si470x_set_register;
354 radio->fops_open = si470x_fops_open;
355 radio->fops_release = si470x_fops_release;
356 radio->vidioc_querycap = si470x_vidioc_querycap;
358 retval = v4l2_device_register(&client->dev, &radio->v4l2_dev);
360 dev_err(&client->dev, "couldn't register v4l2_device\n");
364 v4l2_ctrl_handler_init(&radio->hdl, 2);
365 v4l2_ctrl_new_std(&radio->hdl, &si470x_ctrl_ops,
366 V4L2_CID_AUDIO_MUTE, 0, 1, 1, 1);
367 v4l2_ctrl_new_std(&radio->hdl, &si470x_ctrl_ops,
368 V4L2_CID_AUDIO_VOLUME, 0, 15, 1, 15);
369 if (radio->hdl.error) {
370 retval = radio->hdl.error;
371 dev_err(&client->dev, "couldn't register control\n");
375 /* video device initialization */
376 radio->videodev = si470x_viddev_template;
377 radio->videodev.ctrl_handler = &radio->hdl;
378 radio->videodev.lock = &radio->lock;
379 radio->videodev.v4l2_dev = &radio->v4l2_dev;
380 radio->videodev.release = video_device_release_empty;
381 radio->videodev.device_caps =
382 V4L2_CAP_HW_FREQ_SEEK | V4L2_CAP_READWRITE | V4L2_CAP_TUNER |
383 V4L2_CAP_RADIO | V4L2_CAP_RDS_CAPTURE;
384 video_set_drvdata(&radio->videodev, radio);
386 radio->gpio_reset = devm_gpiod_get_optional(&client->dev, "reset",
388 if (IS_ERR(radio->gpio_reset)) {
389 retval = PTR_ERR(radio->gpio_reset);
390 dev_err(&client->dev, "Failed to request gpio: %d\n", retval);
394 if (radio->gpio_reset)
395 gpiod_set_value(radio->gpio_reset, 1);
397 /* power up : need 110ms */
398 radio->registers[POWERCFG] = POWERCFG_ENABLE;
399 if (si470x_set_register(radio, POWERCFG) < 0) {
405 /* get device and chip versions */
406 if (si470x_get_all_registers(radio) < 0) {
410 dev_info(&client->dev, "DeviceID=0x%4.4hx ChipID=0x%4.4hx\n",
411 radio->registers[DEVICEID], radio->registers[SI_CHIPID]);
412 if ((radio->registers[SI_CHIPID] & SI_CHIPID_FIRMWARE) < RADIO_FW_VERSION) {
413 dev_warn(&client->dev,
414 "This driver is known to work with firmware version %hu,\n",
416 dev_warn(&client->dev,
417 "but the device has firmware version %hu.\n",
418 radio->registers[SI_CHIPID] & SI_CHIPID_FIRMWARE);
422 /* give out version warning */
423 if (version_warning == 1) {
424 dev_warn(&client->dev,
425 "If you have some trouble using this driver,\n");
426 dev_warn(&client->dev,
427 "please report to V4L ML at linux-media@vger.kernel.org\n");
430 /* set initial frequency */
431 si470x_set_freq(radio, 87.5 * FREQ_MUL); /* available in all regions */
433 /* rds buffer allocation */
434 radio->buf_size = rds_buf * 3;
435 radio->buffer = devm_kmalloc(&client->dev, radio->buf_size, GFP_KERNEL);
436 if (!radio->buffer) {
441 /* rds buffer configuration */
444 init_waitqueue_head(&radio->read_queue);
446 retval = devm_request_threaded_irq(&client->dev, client->irq, NULL,
447 si470x_i2c_interrupt,
448 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
451 dev_err(&client->dev, "Failed to register interrupt\n");
455 /* register video device */
456 retval = video_register_device(&radio->videodev, VFL_TYPE_RADIO,
459 dev_warn(&client->dev, "Could not register video device\n");
462 i2c_set_clientdata(client, radio);
466 v4l2_ctrl_handler_free(&radio->hdl);
468 v4l2_device_unregister(&radio->v4l2_dev);
475 * si470x_i2c_remove - remove the device
477 static int si470x_i2c_remove(struct i2c_client *client)
479 struct si470x_device *radio = i2c_get_clientdata(client);
481 video_unregister_device(&radio->videodev);
483 if (radio->gpio_reset)
484 gpiod_set_value(radio->gpio_reset, 0);
490 #ifdef CONFIG_PM_SLEEP
492 * si470x_i2c_suspend - suspend the device
494 static int si470x_i2c_suspend(struct device *dev)
496 struct i2c_client *client = to_i2c_client(dev);
497 struct si470x_device *radio = i2c_get_clientdata(client);
500 radio->registers[POWERCFG] |= POWERCFG_DISABLE;
501 if (si470x_set_register(radio, POWERCFG) < 0)
509 * si470x_i2c_resume - resume the device
511 static int si470x_i2c_resume(struct device *dev)
513 struct i2c_client *client = to_i2c_client(dev);
514 struct si470x_device *radio = i2c_get_clientdata(client);
516 /* power up : need 110ms */
517 radio->registers[POWERCFG] |= POWERCFG_ENABLE;
518 if (si470x_set_register(radio, POWERCFG) < 0)
525 static SIMPLE_DEV_PM_OPS(si470x_i2c_pm, si470x_i2c_suspend, si470x_i2c_resume);
528 #if IS_ENABLED(CONFIG_OF)
529 static const struct of_device_id si470x_of_match[] = {
530 { .compatible = "silabs,si470x" },
533 MODULE_DEVICE_TABLE(of, si470x_of_match);
537 * si470x_i2c_driver - i2c driver interface
539 static struct i2c_driver si470x_i2c_driver = {
542 .of_match_table = of_match_ptr(si470x_of_match),
543 #ifdef CONFIG_PM_SLEEP
544 .pm = &si470x_i2c_pm,
547 .probe = si470x_i2c_probe,
548 .remove = si470x_i2c_remove,
549 .id_table = si470x_i2c_id,
552 module_i2c_driver(si470x_i2c_driver);
554 MODULE_LICENSE("GPL");
555 MODULE_AUTHOR(DRIVER_AUTHOR);
556 MODULE_DESCRIPTION(DRIVER_DESC);
557 MODULE_VERSION(DRIVER_VERSION);