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_KERNEL_VERSION KERNEL_VERSION(1, 0, 1)
28 #define DRIVER_CARD "Silicon Labs Si470x FM Radio Receiver"
29 #define DRIVER_DESC "I2C radio driver for Si470x FM Radio Receivers"
30 #define DRIVER_VERSION "1.0.1"
33 #include <linux/i2c.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 * General Driver Functions - DISCONNECT_CHECK
166 **************************************************************************/
169 * si470x_disconnect_check - check whether radio disconnects
171 int si470x_disconnect_check(struct si470x_device
*radio
)
178 /**************************************************************************
179 * File Operations Interface
180 **************************************************************************/
183 * si470x_fops_open - file open
185 int si470x_fops_open(struct file
*file
)
187 struct si470x_device
*radio
= video_drvdata(file
);
190 mutex_lock(&radio
->lock
);
193 if (radio
->users
== 1) {
195 retval
= si470x_start(radio
);
199 /* enable RDS interrupt */
200 radio
->registers
[SYSCONFIG1
] |= SYSCONFIG1_RDSIEN
;
201 radio
->registers
[SYSCONFIG1
] &= ~SYSCONFIG1_GPIO2
;
202 radio
->registers
[SYSCONFIG1
] |= 0x1 << 2;
203 retval
= si470x_set_register(radio
, SYSCONFIG1
);
207 mutex_unlock(&radio
->lock
);
213 * si470x_fops_release - file release
215 int si470x_fops_release(struct file
*file
)
217 struct si470x_device
*radio
= video_drvdata(file
);
224 mutex_lock(&radio
->lock
);
226 if (radio
->users
== 0)
228 retval
= si470x_stop(radio
);
230 mutex_unlock(&radio
->lock
);
237 /**************************************************************************
238 * Video4Linux Interface
239 **************************************************************************/
242 * si470x_vidioc_querycap - query device capabilities
244 int si470x_vidioc_querycap(struct file
*file
, void *priv
,
245 struct v4l2_capability
*capability
)
247 strlcpy(capability
->driver
, DRIVER_NAME
, sizeof(capability
->driver
));
248 strlcpy(capability
->card
, DRIVER_CARD
, sizeof(capability
->card
));
249 capability
->version
= DRIVER_KERNEL_VERSION
;
250 capability
->capabilities
= V4L2_CAP_HW_FREQ_SEEK
|
251 V4L2_CAP_TUNER
| V4L2_CAP_RADIO
;
258 /**************************************************************************
260 **************************************************************************/
263 * si470x_i2c_interrupt_work - rds processing function
265 static void si470x_i2c_interrupt_work(struct work_struct
*work
)
267 struct si470x_device
*radio
= container_of(work
,
268 struct si470x_device
, radio_work
);
270 unsigned char blocknum
;
271 unsigned short bler
; /* rds block errors */
273 unsigned char tmpbuf
[3];
277 if ((radio
->registers
[SYSCONFIG1
] & SYSCONFIG1_RDS
) == 0)
280 /* Update RDS registers */
281 for (regnr
= 0; regnr
< RDS_REGISTER_NUM
; regnr
++) {
282 retval
= si470x_get_register(radio
, STATUSRSSI
+ regnr
);
288 if ((radio
->registers
[STATUSRSSI
] & STATUSRSSI_RDSR
) == 0)
289 /* No RDS group ready, better luck next time */
292 for (blocknum
= 0; blocknum
< 4; blocknum
++) {
295 bler
= (radio
->registers
[STATUSRSSI
] &
296 STATUSRSSI_BLERA
) >> 9;
297 rds
= radio
->registers
[RDSA
];
300 bler
= (radio
->registers
[READCHAN
] &
301 READCHAN_BLERB
) >> 14;
302 rds
= radio
->registers
[RDSB
];
305 bler
= (radio
->registers
[READCHAN
] &
306 READCHAN_BLERC
) >> 12;
307 rds
= radio
->registers
[RDSC
];
310 bler
= (radio
->registers
[READCHAN
] &
311 READCHAN_BLERD
) >> 10;
312 rds
= radio
->registers
[RDSD
];
316 /* Fill the V4L2 RDS buffer */
317 put_unaligned_le16(rds
, &tmpbuf
);
318 tmpbuf
[2] = blocknum
; /* offset name */
319 tmpbuf
[2] |= blocknum
<< 3; /* received offset */
320 if (bler
> max_rds_errors
)
321 tmpbuf
[2] |= 0x80; /* uncorrectable errors */
323 tmpbuf
[2] |= 0x40; /* corrected error(s) */
325 /* copy RDS block to internal buffer */
326 memcpy(&radio
->buffer
[radio
->wr_index
], &tmpbuf
, 3);
327 radio
->wr_index
+= 3;
329 /* wrap write pointer */
330 if (radio
->wr_index
>= radio
->buf_size
)
333 /* check for overflow */
334 if (radio
->wr_index
== radio
->rd_index
) {
335 /* increment and wrap read pointer */
336 radio
->rd_index
+= 3;
337 if (radio
->rd_index
>= radio
->buf_size
)
342 if (radio
->wr_index
!= radio
->rd_index
)
343 wake_up_interruptible(&radio
->read_queue
);
348 * si470x_i2c_interrupt - interrupt handler
350 static irqreturn_t
si470x_i2c_interrupt(int irq
, void *dev_id
)
352 struct si470x_device
*radio
= dev_id
;
354 if (!work_pending(&radio
->radio_work
))
355 schedule_work(&radio
->radio_work
);
362 * si470x_i2c_probe - probe for the device
364 static int __devinit
si470x_i2c_probe(struct i2c_client
*client
,
365 const struct i2c_device_id
*id
)
367 struct si470x_device
*radio
;
369 unsigned char version_warning
= 0;
371 /* private data allocation and initialization */
372 radio
= kzalloc(sizeof(struct si470x_device
), GFP_KERNEL
);
378 INIT_WORK(&radio
->radio_work
, si470x_i2c_interrupt_work
);
380 radio
->client
= client
;
381 mutex_init(&radio
->lock
);
383 /* video device allocation and initialization */
384 radio
->videodev
= video_device_alloc();
385 if (!radio
->videodev
) {
389 memcpy(radio
->videodev
, &si470x_viddev_template
,
390 sizeof(si470x_viddev_template
));
391 video_set_drvdata(radio
->videodev
, radio
);
393 /* power up : need 110ms */
394 radio
->registers
[POWERCFG
] = POWERCFG_ENABLE
;
395 if (si470x_set_register(radio
, POWERCFG
) < 0) {
401 /* get device and chip versions */
402 if (si470x_get_all_registers(radio
) < 0) {
406 dev_info(&client
->dev
, "DeviceID=0x%4.4hx ChipID=0x%4.4hx\n",
407 radio
->registers
[DEVICEID
], radio
->registers
[CHIPID
]);
408 if ((radio
->registers
[CHIPID
] & CHIPID_FIRMWARE
) < RADIO_FW_VERSION
) {
409 dev_warn(&client
->dev
,
410 "This driver is known to work with "
411 "firmware version %hu,\n", RADIO_FW_VERSION
);
412 dev_warn(&client
->dev
,
413 "but the device has firmware version %hu.\n",
414 radio
->registers
[CHIPID
] & CHIPID_FIRMWARE
);
418 /* give out version warning */
419 if (version_warning
== 1) {
420 dev_warn(&client
->dev
,
421 "If you have some trouble using this driver,\n");
422 dev_warn(&client
->dev
,
423 "please report to V4L ML at "
424 "linux-media@vger.kernel.org\n");
427 /* set initial frequency */
428 si470x_set_freq(radio
, 87.5 * FREQ_MUL
); /* available in all regions */
430 /* rds buffer allocation */
431 radio
->buf_size
= rds_buf
* 3;
432 radio
->buffer
= kmalloc(radio
->buf_size
, GFP_KERNEL
);
433 if (!radio
->buffer
) {
438 /* rds buffer configuration */
441 init_waitqueue_head(&radio
->read_queue
);
443 retval
= request_irq(client
->irq
, si470x_i2c_interrupt
,
444 IRQF_TRIGGER_FALLING
, DRIVER_NAME
, radio
);
446 dev_err(&client
->dev
, "Failed to register interrupt\n");
450 /* register video device */
451 retval
= video_register_device(radio
->videodev
, VFL_TYPE_RADIO
,
454 dev_warn(&client
->dev
, "Could not register video device\n");
457 i2c_set_clientdata(client
, radio
);
461 free_irq(client
->irq
, radio
);
463 kfree(radio
->buffer
);
465 video_device_release(radio
->videodev
);
474 * si470x_i2c_remove - remove the device
476 static __devexit
int si470x_i2c_remove(struct i2c_client
*client
)
478 struct si470x_device
*radio
= i2c_get_clientdata(client
);
480 free_irq(client
->irq
, radio
);
481 cancel_work_sync(&radio
->radio_work
);
482 video_unregister_device(radio
->videodev
);
484 i2c_set_clientdata(client
, NULL
);
492 * si470x_i2c_suspend - suspend the device
494 static int si470x_i2c_suspend(struct i2c_client
*client
, pm_message_t mesg
)
496 struct si470x_device
*radio
= i2c_get_clientdata(client
);
499 radio
->registers
[POWERCFG
] |= POWERCFG_DISABLE
;
500 if (si470x_set_register(radio
, POWERCFG
) < 0)
508 * si470x_i2c_resume - resume the device
510 static int si470x_i2c_resume(struct i2c_client
*client
)
512 struct si470x_device
*radio
= i2c_get_clientdata(client
);
514 /* power up : need 110ms */
515 radio
->registers
[POWERCFG
] |= POWERCFG_ENABLE
;
516 if (si470x_set_register(radio
, POWERCFG
) < 0)
523 #define si470x_i2c_suspend NULL
524 #define si470x_i2c_resume NULL
529 * si470x_i2c_driver - i2c driver interface
531 static struct i2c_driver si470x_i2c_driver
= {
534 .owner
= THIS_MODULE
,
536 .probe
= si470x_i2c_probe
,
537 .remove
= __devexit_p(si470x_i2c_remove
),
538 .suspend
= si470x_i2c_suspend
,
539 .resume
= si470x_i2c_resume
,
540 .id_table
= si470x_i2c_id
,
545 /**************************************************************************
547 **************************************************************************/
550 * si470x_i2c_init - module init
552 static int __init
si470x_i2c_init(void)
554 printk(KERN_INFO DRIVER_DESC
", Version " DRIVER_VERSION
"\n");
555 return i2c_add_driver(&si470x_i2c_driver
);
560 * si470x_i2c_exit - module exit
562 static void __exit
si470x_i2c_exit(void)
564 i2c_del_driver(&si470x_i2c_driver
);
568 module_init(si470x_i2c_init
);
569 module_exit(si470x_i2c_exit
);
571 MODULE_LICENSE("GPL");
572 MODULE_AUTHOR(DRIVER_AUTHOR
);
573 MODULE_DESCRIPTION(DRIVER_DESC
);
574 MODULE_VERSION(DRIVER_VERSION
);