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.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
25 /* driver definitions */
26 #define DRIVER_AUTHOR "Joonyoung Shim <jy0922.shim@samsung.com>";
27 #define DRIVER_CARD "Silicon Labs Si470x FM Radio Receiver"
28 #define DRIVER_DESC "I2C radio driver for Si470x FM Radio Receivers"
29 #define DRIVER_VERSION "1.0.2"
32 #include <linux/i2c.h>
33 #include <linux/slab.h>
34 #include <linux/delay.h>
35 #include <linux/interrupt.h>
37 #include "radio-si470x.h"
40 /* I2C Device ID List */
41 static const struct i2c_device_id si470x_i2c_id[] = {
44 /* Terminating entry */
47 MODULE_DEVICE_TABLE(i2c, si470x_i2c_id);
51 /**************************************************************************
53 **************************************************************************/
56 static int radio_nr = -1;
57 module_param(radio_nr, int, 0444);
58 MODULE_PARM_DESC(radio_nr, "Radio Nr");
60 /* RDS buffer blocks */
61 static unsigned int rds_buf = 100;
62 module_param(rds_buf, uint, 0444);
63 MODULE_PARM_DESC(rds_buf, "RDS buffer entries: *100*");
65 /* RDS maximum block errors */
66 static unsigned short max_rds_errors = 1;
67 /* 0 means 0 errors requiring correction */
68 /* 1 means 1-2 errors requiring correction (used by original USBRadio.exe) */
69 /* 2 means 3-5 errors requiring correction */
70 /* 3 means 6+ errors or errors in checkword, correction not possible */
71 module_param(max_rds_errors, ushort, 0644);
72 MODULE_PARM_DESC(max_rds_errors, "RDS maximum block errors: *1*");
76 /**************************************************************************
78 **************************************************************************/
80 /* Write starts with the upper byte of register 0x02 */
81 #define WRITE_REG_NUM 8
82 #define WRITE_INDEX(i) (i + 0x02)
84 /* Read starts with the upper byte of register 0x0a */
85 #define READ_REG_NUM RADIO_REGISTER_NUM
86 #define READ_INDEX(i) ((i + RADIO_REGISTER_NUM - 0x0a) % READ_REG_NUM)
90 /**************************************************************************
91 * General Driver Functions - REGISTERs
92 **************************************************************************/
95 * si470x_get_register - read register
97 int si470x_get_register(struct si470x_device *radio, int regnr)
99 u16 buf[READ_REG_NUM];
100 struct i2c_msg msgs[1] = {
101 { radio->client->addr, I2C_M_RD, 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 u16 buf[WRITE_REG_NUM];
121 struct i2c_msg msgs[1] = {
122 { radio->client->addr, 0, sizeof(u16) * WRITE_REG_NUM,
126 for (i = 0; i < WRITE_REG_NUM; i++)
127 buf[i] = __cpu_to_be16(radio->registers[WRITE_INDEX(i)]);
129 if (i2c_transfer(radio->client->adapter, msgs, 1) != 1)
137 /**************************************************************************
138 * General Driver Functions - ENTIRE REGISTERS
139 **************************************************************************/
142 * si470x_get_all_registers - read entire registers
144 static int si470x_get_all_registers(struct si470x_device *radio)
147 u16 buf[READ_REG_NUM];
148 struct i2c_msg msgs[1] = {
149 { radio->client->addr, I2C_M_RD, sizeof(u16) * READ_REG_NUM,
153 if (i2c_transfer(radio->client->adapter, msgs, 1) != 1)
156 for (i = 0; i < READ_REG_NUM; i++)
157 radio->registers[i] = __be16_to_cpu(buf[READ_INDEX(i)]);
164 /**************************************************************************
165 * File Operations Interface
166 **************************************************************************/
169 * si470x_fops_open - file open
171 int si470x_fops_open(struct file *file)
173 struct si470x_device *radio = video_drvdata(file);
174 int retval = v4l2_fh_open(file);
179 if (v4l2_fh_is_singular_file(file)) {
181 retval = si470x_start(radio);
185 /* enable RDS / STC interrupt */
186 radio->registers[SYSCONFIG1] |= SYSCONFIG1_RDSIEN;
187 radio->registers[SYSCONFIG1] |= SYSCONFIG1_STCIEN;
188 radio->registers[SYSCONFIG1] &= ~SYSCONFIG1_GPIO2;
189 radio->registers[SYSCONFIG1] |= 0x1 << 2;
190 retval = si470x_set_register(radio, SYSCONFIG1);
195 v4l2_fh_release(file);
201 * si470x_fops_release - file release
203 int si470x_fops_release(struct file *file)
205 struct si470x_device *radio = video_drvdata(file);
207 if (v4l2_fh_is_singular_file(file))
211 return v4l2_fh_release(file);
216 /**************************************************************************
217 * Video4Linux Interface
218 **************************************************************************/
221 * si470x_vidioc_querycap - query device capabilities
223 int si470x_vidioc_querycap(struct file *file, void *priv,
224 struct v4l2_capability *capability)
226 strlcpy(capability->driver, DRIVER_NAME, sizeof(capability->driver));
227 strlcpy(capability->card, DRIVER_CARD, sizeof(capability->card));
228 capability->capabilities = V4L2_CAP_HW_FREQ_SEEK |
229 V4L2_CAP_TUNER | V4L2_CAP_RADIO;
236 /**************************************************************************
238 **************************************************************************/
241 * si470x_i2c_interrupt - interrupt handler
243 static irqreturn_t si470x_i2c_interrupt(int irq, void *dev_id)
245 struct si470x_device *radio = dev_id;
247 unsigned char blocknum;
248 unsigned short bler; /* rds block errors */
250 unsigned char tmpbuf[3];
253 /* check Seek/Tune Complete */
254 retval = si470x_get_register(radio, STATUSRSSI);
258 if (radio->registers[STATUSRSSI] & STATUSRSSI_STC)
259 complete(&radio->completion);
262 if ((radio->registers[SYSCONFIG1] & SYSCONFIG1_RDS) == 0)
265 /* Update RDS registers */
266 for (regnr = 1; regnr < RDS_REGISTER_NUM; regnr++) {
267 retval = si470x_get_register(radio, STATUSRSSI + regnr);
273 if ((radio->registers[STATUSRSSI] & STATUSRSSI_RDSR) == 0)
274 /* No RDS group ready, better luck next time */
277 for (blocknum = 0; blocknum < 4; blocknum++) {
280 bler = (radio->registers[STATUSRSSI] &
281 STATUSRSSI_BLERA) >> 9;
282 rds = radio->registers[RDSA];
285 bler = (radio->registers[READCHAN] &
286 READCHAN_BLERB) >> 14;
287 rds = radio->registers[RDSB];
290 bler = (radio->registers[READCHAN] &
291 READCHAN_BLERC) >> 12;
292 rds = radio->registers[RDSC];
295 bler = (radio->registers[READCHAN] &
296 READCHAN_BLERD) >> 10;
297 rds = radio->registers[RDSD];
301 /* Fill the V4L2 RDS buffer */
302 put_unaligned_le16(rds, &tmpbuf);
303 tmpbuf[2] = blocknum; /* offset name */
304 tmpbuf[2] |= blocknum << 3; /* received offset */
305 if (bler > max_rds_errors)
306 tmpbuf[2] |= 0x80; /* uncorrectable errors */
308 tmpbuf[2] |= 0x40; /* corrected error(s) */
310 /* copy RDS block to internal buffer */
311 memcpy(&radio->buffer[radio->wr_index], &tmpbuf, 3);
312 radio->wr_index += 3;
314 /* wrap write pointer */
315 if (radio->wr_index >= radio->buf_size)
318 /* check for overflow */
319 if (radio->wr_index == radio->rd_index) {
320 /* increment and wrap read pointer */
321 radio->rd_index += 3;
322 if (radio->rd_index >= radio->buf_size)
327 if (radio->wr_index != radio->rd_index)
328 wake_up_interruptible(&radio->read_queue);
336 * si470x_i2c_probe - probe for the device
338 static int __devinit si470x_i2c_probe(struct i2c_client *client,
339 const struct i2c_device_id *id)
341 struct si470x_device *radio;
343 unsigned char version_warning = 0;
345 /* private data allocation and initialization */
346 radio = kzalloc(sizeof(struct si470x_device), GFP_KERNEL);
352 radio->client = client;
353 mutex_init(&radio->lock);
354 init_completion(&radio->completion);
356 /* video device initialization */
357 radio->videodev = si470x_viddev_template;
358 video_set_drvdata(&radio->videodev, radio);
360 /* power up : need 110ms */
361 radio->registers[POWERCFG] = POWERCFG_ENABLE;
362 if (si470x_set_register(radio, POWERCFG) < 0) {
368 /* get device and chip versions */
369 if (si470x_get_all_registers(radio) < 0) {
373 dev_info(&client->dev, "DeviceID=0x%4.4hx ChipID=0x%4.4hx\n",
374 radio->registers[DEVICEID], radio->registers[CHIPID]);
375 if ((radio->registers[CHIPID] & CHIPID_FIRMWARE) < RADIO_FW_VERSION) {
376 dev_warn(&client->dev,
377 "This driver is known to work with "
378 "firmware version %hu,\n", RADIO_FW_VERSION);
379 dev_warn(&client->dev,
380 "but the device has firmware version %hu.\n",
381 radio->registers[CHIPID] & CHIPID_FIRMWARE);
385 /* give out version warning */
386 if (version_warning == 1) {
387 dev_warn(&client->dev,
388 "If you have some trouble using this driver,\n");
389 dev_warn(&client->dev,
390 "please report to V4L ML at "
391 "linux-media@vger.kernel.org\n");
394 /* set initial frequency */
395 si470x_set_freq(radio, 87.5 * FREQ_MUL); /* available in all regions */
397 /* rds buffer allocation */
398 radio->buf_size = rds_buf * 3;
399 radio->buffer = kmalloc(radio->buf_size, GFP_KERNEL);
400 if (!radio->buffer) {
405 /* rds buffer configuration */
408 init_waitqueue_head(&radio->read_queue);
410 retval = request_threaded_irq(client->irq, NULL, si470x_i2c_interrupt,
411 IRQF_TRIGGER_FALLING, DRIVER_NAME, radio);
413 dev_err(&client->dev, "Failed to register interrupt\n");
417 /* register video device */
418 retval = video_register_device(&radio->videodev, VFL_TYPE_RADIO,
421 dev_warn(&client->dev, "Could not register video device\n");
424 i2c_set_clientdata(client, radio);
428 free_irq(client->irq, radio);
430 kfree(radio->buffer);
439 * si470x_i2c_remove - remove the device
441 static __devexit int si470x_i2c_remove(struct i2c_client *client)
443 struct si470x_device *radio = i2c_get_clientdata(client);
445 free_irq(client->irq, radio);
446 video_unregister_device(&radio->videodev);
455 * si470x_i2c_suspend - suspend the device
457 static int si470x_i2c_suspend(struct device *dev)
459 struct i2c_client *client = to_i2c_client(dev);
460 struct si470x_device *radio = i2c_get_clientdata(client);
463 radio->registers[POWERCFG] |= POWERCFG_DISABLE;
464 if (si470x_set_register(radio, POWERCFG) < 0)
472 * si470x_i2c_resume - resume the device
474 static int si470x_i2c_resume(struct device *dev)
476 struct i2c_client *client = to_i2c_client(dev);
477 struct si470x_device *radio = i2c_get_clientdata(client);
479 /* power up : need 110ms */
480 radio->registers[POWERCFG] |= POWERCFG_ENABLE;
481 if (si470x_set_register(radio, POWERCFG) < 0)
488 static SIMPLE_DEV_PM_OPS(si470x_i2c_pm, si470x_i2c_suspend, si470x_i2c_resume);
493 * si470x_i2c_driver - i2c driver interface
495 static struct i2c_driver si470x_i2c_driver = {
498 .owner = THIS_MODULE,
500 .pm = &si470x_i2c_pm,
503 .probe = si470x_i2c_probe,
504 .remove = __devexit_p(si470x_i2c_remove),
505 .id_table = si470x_i2c_id,
508 module_i2c_driver(si470x_i2c_driver);
510 MODULE_LICENSE("GPL");
511 MODULE_AUTHOR(DRIVER_AUTHOR);
512 MODULE_DESCRIPTION(DRIVER_DESC);
513 MODULE_VERSION(DRIVER_VERSION);