2 * drivers/media/radio/si470x/radio-si470x-i2c.c
4 * I2C driver for radios with Silicon Labs Si470x FM Radio Receivers
6 * Copyright (c) 2009 Samsung Electronics Co.Ltd
7 * Author: Joonyoung Shim <jy0922.shim@samsung.com>
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.
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.
21 /* driver definitions */
22 #define DRIVER_AUTHOR "Joonyoung Shim <jy0922.shim@samsung.com>";
23 #define DRIVER_CARD "Silicon Labs Si470x FM Radio"
24 #define DRIVER_DESC "I2C radio driver for Si470x FM Radio Receivers"
25 #define DRIVER_VERSION "1.0.2"
28 #include <linux/i2c.h>
29 #include <linux/slab.h>
30 #include <linux/delay.h>
31 #include <linux/interrupt.h>
33 #include "radio-si470x.h"
36 /* I2C Device ID List */
37 static const struct i2c_device_id si470x_i2c_id[] = {
40 /* Terminating entry */
43 MODULE_DEVICE_TABLE(i2c, si470x_i2c_id);
47 /**************************************************************************
49 **************************************************************************/
52 static int radio_nr = -1;
53 module_param(radio_nr, int, 0444);
54 MODULE_PARM_DESC(radio_nr, "Radio Nr");
56 /* RDS buffer blocks */
57 static unsigned int rds_buf = 100;
58 module_param(rds_buf, uint, 0444);
59 MODULE_PARM_DESC(rds_buf, "RDS buffer entries: *100*");
61 /* RDS maximum block errors */
62 static unsigned short max_rds_errors = 1;
63 /* 0 means 0 errors requiring correction */
64 /* 1 means 1-2 errors requiring correction (used by original USBRadio.exe) */
65 /* 2 means 3-5 errors requiring correction */
66 /* 3 means 6+ errors or errors in checkword, correction not possible */
67 module_param(max_rds_errors, ushort, 0644);
68 MODULE_PARM_DESC(max_rds_errors, "RDS maximum block errors: *1*");
72 /**************************************************************************
74 **************************************************************************/
76 /* Write starts with the upper byte of register 0x02 */
77 #define WRITE_REG_NUM 8
78 #define WRITE_INDEX(i) (i + 0x02)
80 /* Read starts with the upper byte of register 0x0a */
81 #define READ_REG_NUM RADIO_REGISTER_NUM
82 #define READ_INDEX(i) ((i + RADIO_REGISTER_NUM - 0x0a) % READ_REG_NUM)
86 /**************************************************************************
87 * General Driver Functions - REGISTERs
88 **************************************************************************/
91 * si470x_get_register - read register
93 int si470x_get_register(struct si470x_device *radio, int regnr)
95 __be16 buf[READ_REG_NUM];
96 struct i2c_msg msgs[1] = {
98 .addr = radio->client->addr,
100 .len = sizeof(u16) * READ_REG_NUM,
105 if (i2c_transfer(radio->client->adapter, msgs, 1) != 1)
108 radio->registers[regnr] = __be16_to_cpu(buf[READ_INDEX(regnr)]);
115 * si470x_set_register - write register
117 int si470x_set_register(struct si470x_device *radio, int regnr)
120 __be16 buf[WRITE_REG_NUM];
121 struct i2c_msg msgs[1] = {
123 .addr = radio->client->addr,
124 .len = sizeof(u16) * WRITE_REG_NUM,
129 for (i = 0; i < WRITE_REG_NUM; i++)
130 buf[i] = __cpu_to_be16(radio->registers[WRITE_INDEX(i)]);
132 if (i2c_transfer(radio->client->adapter, msgs, 1) != 1)
140 /**************************************************************************
141 * General Driver Functions - ENTIRE REGISTERS
142 **************************************************************************/
145 * si470x_get_all_registers - read entire registers
147 static int si470x_get_all_registers(struct si470x_device *radio)
150 __be16 buf[READ_REG_NUM];
151 struct i2c_msg msgs[1] = {
153 .addr = radio->client->addr,
155 .len = sizeof(u16) * READ_REG_NUM,
160 if (i2c_transfer(radio->client->adapter, msgs, 1) != 1)
163 for (i = 0; i < READ_REG_NUM; i++)
164 radio->registers[i] = __be16_to_cpu(buf[READ_INDEX(i)]);
171 /**************************************************************************
172 * File Operations Interface
173 **************************************************************************/
176 * si470x_fops_open - file open
178 int si470x_fops_open(struct file *file)
180 struct si470x_device *radio = video_drvdata(file);
181 int retval = v4l2_fh_open(file);
186 if (v4l2_fh_is_singular_file(file)) {
188 retval = si470x_start(radio);
192 /* enable RDS / STC interrupt */
193 radio->registers[SYSCONFIG1] |= SYSCONFIG1_RDSIEN;
194 radio->registers[SYSCONFIG1] |= SYSCONFIG1_STCIEN;
195 radio->registers[SYSCONFIG1] &= ~SYSCONFIG1_GPIO2;
196 radio->registers[SYSCONFIG1] |= 0x1 << 2;
197 retval = si470x_set_register(radio, SYSCONFIG1);
202 v4l2_fh_release(file);
208 * si470x_fops_release - file release
210 int si470x_fops_release(struct file *file)
212 struct si470x_device *radio = video_drvdata(file);
214 if (v4l2_fh_is_singular_file(file))
218 return v4l2_fh_release(file);
223 /**************************************************************************
224 * Video4Linux Interface
225 **************************************************************************/
228 * si470x_vidioc_querycap - query device capabilities
230 int si470x_vidioc_querycap(struct file *file, void *priv,
231 struct v4l2_capability *capability)
233 strlcpy(capability->driver, DRIVER_NAME, sizeof(capability->driver));
234 strlcpy(capability->card, DRIVER_CARD, sizeof(capability->card));
235 capability->device_caps = V4L2_CAP_HW_FREQ_SEEK | V4L2_CAP_READWRITE |
236 V4L2_CAP_TUNER | V4L2_CAP_RADIO | V4L2_CAP_RDS_CAPTURE;
237 capability->capabilities = capability->device_caps | V4L2_CAP_DEVICE_CAPS;
244 /**************************************************************************
246 **************************************************************************/
249 * si470x_i2c_interrupt - interrupt handler
251 static irqreturn_t si470x_i2c_interrupt(int irq, void *dev_id)
253 struct si470x_device *radio = dev_id;
255 unsigned char blocknum;
256 unsigned short bler; /* rds block errors */
258 unsigned char tmpbuf[3];
261 /* check Seek/Tune Complete */
262 retval = si470x_get_register(radio, STATUSRSSI);
266 if (radio->registers[STATUSRSSI] & STATUSRSSI_STC)
267 complete(&radio->completion);
270 if ((radio->registers[SYSCONFIG1] & SYSCONFIG1_RDS) == 0)
273 /* Update RDS registers */
274 for (regnr = 1; regnr < RDS_REGISTER_NUM; regnr++) {
275 retval = si470x_get_register(radio, STATUSRSSI + regnr);
281 if ((radio->registers[STATUSRSSI] & STATUSRSSI_RDSR) == 0)
282 /* No RDS group ready, better luck next time */
285 for (blocknum = 0; blocknum < 4; blocknum++) {
288 bler = (radio->registers[STATUSRSSI] &
289 STATUSRSSI_BLERA) >> 9;
290 rds = radio->registers[RDSA];
293 bler = (radio->registers[READCHAN] &
294 READCHAN_BLERB) >> 14;
295 rds = radio->registers[RDSB];
298 bler = (radio->registers[READCHAN] &
299 READCHAN_BLERC) >> 12;
300 rds = radio->registers[RDSC];
303 bler = (radio->registers[READCHAN] &
304 READCHAN_BLERD) >> 10;
305 rds = radio->registers[RDSD];
309 /* Fill the V4L2 RDS buffer */
310 put_unaligned_le16(rds, &tmpbuf);
311 tmpbuf[2] = blocknum; /* offset name */
312 tmpbuf[2] |= blocknum << 3; /* received offset */
313 if (bler > max_rds_errors)
314 tmpbuf[2] |= 0x80; /* uncorrectable errors */
316 tmpbuf[2] |= 0x40; /* corrected error(s) */
318 /* copy RDS block to internal buffer */
319 memcpy(&radio->buffer[radio->wr_index], &tmpbuf, 3);
320 radio->wr_index += 3;
322 /* wrap write pointer */
323 if (radio->wr_index >= radio->buf_size)
326 /* check for overflow */
327 if (radio->wr_index == radio->rd_index) {
328 /* increment and wrap read pointer */
329 radio->rd_index += 3;
330 if (radio->rd_index >= radio->buf_size)
335 if (radio->wr_index != radio->rd_index)
336 wake_up_interruptible(&radio->read_queue);
344 * si470x_i2c_probe - probe for the device
346 static int si470x_i2c_probe(struct i2c_client *client,
347 const struct i2c_device_id *id)
349 struct si470x_device *radio;
351 unsigned char version_warning = 0;
353 /* private data allocation and initialization */
354 radio = kzalloc(sizeof(struct si470x_device), GFP_KERNEL);
360 radio->client = client;
361 radio->band = 1; /* Default to 76 - 108 MHz */
362 mutex_init(&radio->lock);
363 init_completion(&radio->completion);
365 /* video device initialization */
366 radio->videodev = si470x_viddev_template;
367 video_set_drvdata(&radio->videodev, radio);
369 /* power up : need 110ms */
370 radio->registers[POWERCFG] = POWERCFG_ENABLE;
371 if (si470x_set_register(radio, POWERCFG) < 0) {
377 /* get device and chip versions */
378 if (si470x_get_all_registers(radio) < 0) {
382 dev_info(&client->dev, "DeviceID=0x%4.4hx ChipID=0x%4.4hx\n",
383 radio->registers[DEVICEID], radio->registers[SI_CHIPID]);
384 if ((radio->registers[SI_CHIPID] & SI_CHIPID_FIRMWARE) < RADIO_FW_VERSION) {
385 dev_warn(&client->dev,
386 "This driver is known to work with firmware version %hu,\n",
388 dev_warn(&client->dev,
389 "but the device has firmware version %hu.\n",
390 radio->registers[SI_CHIPID] & SI_CHIPID_FIRMWARE);
394 /* give out version warning */
395 if (version_warning == 1) {
396 dev_warn(&client->dev,
397 "If you have some trouble using this driver,\n");
398 dev_warn(&client->dev,
399 "please report to V4L ML at linux-media@vger.kernel.org\n");
402 /* set initial frequency */
403 si470x_set_freq(radio, 87.5 * FREQ_MUL); /* available in all regions */
405 /* rds buffer allocation */
406 radio->buf_size = rds_buf * 3;
407 radio->buffer = kmalloc(radio->buf_size, GFP_KERNEL);
408 if (!radio->buffer) {
413 /* rds buffer configuration */
416 init_waitqueue_head(&radio->read_queue);
418 retval = request_threaded_irq(client->irq, NULL, si470x_i2c_interrupt,
419 IRQF_TRIGGER_FALLING | IRQF_ONESHOT, DRIVER_NAME,
422 dev_err(&client->dev, "Failed to register interrupt\n");
426 /* register video device */
427 retval = video_register_device(&radio->videodev, VFL_TYPE_RADIO,
430 dev_warn(&client->dev, "Could not register video device\n");
433 i2c_set_clientdata(client, radio);
437 free_irq(client->irq, radio);
439 kfree(radio->buffer);
448 * si470x_i2c_remove - remove the device
450 static int si470x_i2c_remove(struct i2c_client *client)
452 struct si470x_device *radio = i2c_get_clientdata(client);
454 free_irq(client->irq, radio);
455 video_unregister_device(&radio->videodev);
457 v4l2_ctrl_handler_free(&radio->hdl);
458 v4l2_device_unregister(&radio->v4l2_dev);
464 #ifdef CONFIG_PM_SLEEP
466 * si470x_i2c_suspend - suspend the device
468 static int si470x_i2c_suspend(struct device *dev)
470 struct i2c_client *client = to_i2c_client(dev);
471 struct si470x_device *radio = i2c_get_clientdata(client);
474 radio->registers[POWERCFG] |= POWERCFG_DISABLE;
475 if (si470x_set_register(radio, POWERCFG) < 0)
483 * si470x_i2c_resume - resume the device
485 static int si470x_i2c_resume(struct device *dev)
487 struct i2c_client *client = to_i2c_client(dev);
488 struct si470x_device *radio = i2c_get_clientdata(client);
490 /* power up : need 110ms */
491 radio->registers[POWERCFG] |= POWERCFG_ENABLE;
492 if (si470x_set_register(radio, POWERCFG) < 0)
499 static SIMPLE_DEV_PM_OPS(si470x_i2c_pm, si470x_i2c_suspend, si470x_i2c_resume);
504 * si470x_i2c_driver - i2c driver interface
506 static struct i2c_driver si470x_i2c_driver = {
509 #ifdef CONFIG_PM_SLEEP
510 .pm = &si470x_i2c_pm,
513 .probe = si470x_i2c_probe,
514 .remove = si470x_i2c_remove,
515 .id_table = si470x_i2c_id,
518 module_i2c_driver(si470x_i2c_driver);
520 MODULE_LICENSE("GPL");
521 MODULE_AUTHOR(DRIVER_AUTHOR);
522 MODULE_DESCRIPTION(DRIVER_DESC);
523 MODULE_VERSION(DRIVER_VERSION);