/*
* drivers/media/radio/si470x/radio-si470x-i2c.c
*
* I2C driver for radios with Silicon Labs Si470x FM Radio Receivers
*
* Copyright (c) 2009 Samsung Electronics Co.Ltd
* Author: Joonyoung Shim <jy0922.shim@samsung.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/* driver definitions */
#define DRIVER_AUTHOR "Joonyoung Shim <jy0922.shim@samsung.com>";
#define DRIVER_KERNEL_VERSION KERNEL_VERSION(1, 0, 1)
#define DRIVER_CARD "Silicon Labs Si470x FM Radio Receiver"
#define DRIVER_DESC "I2C radio driver for Si470x FM Radio Receivers"
#define DRIVER_VERSION "1.0.1"
/* kernel includes */
#include <linux/i2c.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include "radio-si470x.h"
/* I2C Device ID List */
static const struct i2c_device_id si470x_i2c_id[] = {
/* Generic Entry */
{ "si470x", 0 },
/* Terminating entry */
{ }
};
MODULE_DEVICE_TABLE(i2c, si470x_i2c_id);
/**************************************************************************
* Module Parameters
**************************************************************************/
/* Radio Nr */
static int radio_nr = -1;
module_param(radio_nr, int, 0444);
MODULE_PARM_DESC(radio_nr, "Radio Nr");
/* RDS buffer blocks */
static unsigned int rds_buf = 100;
module_param(rds_buf, uint, 0444);
MODULE_PARM_DESC(rds_buf, "RDS buffer entries: *100*");
/* RDS maximum block errors */
static unsigned short max_rds_errors = 1;
/* 0 means 0 errors requiring correction */
/* 1 means 1-2 errors requiring correction (used by original USBRadio.exe) */
/* 2 means 3-5 errors requiring correction */
/* 3 means 6+ errors or errors in checkword, correction not possible */
module_param(max_rds_errors, ushort, 0644);
MODULE_PARM_DESC(max_rds_errors, "RDS maximum block errors: *1*");
/**************************************************************************
* I2C Definitions
**************************************************************************/
/* Write starts with the upper byte of register 0x02 */
#define WRITE_REG_NUM 8
#define WRITE_INDEX(i) (i + 0x02)
/* Read starts with the upper byte of register 0x0a */
#define READ_REG_NUM RADIO_REGISTER_NUM
#define READ_INDEX(i) ((i + RADIO_REGISTER_NUM - 0x0a) % READ_REG_NUM)
/**************************************************************************
* General Driver Functions - REGISTERs
**************************************************************************/
/*
* si470x_get_register - read register
*/
int si470x_get_register(struct si470x_device *radio, int regnr)
{
u16 buf[READ_REG_NUM];
struct i2c_msg msgs[1] = {
{ radio->client->addr, I2C_M_RD, sizeof(u16) * READ_REG_NUM,
(void *)buf },
};
if (i2c_transfer(radio->client->adapter, msgs, 1) != 1)
return -EIO;
radio->registers[regnr] = __be16_to_cpu(buf[READ_INDEX(regnr)]);
return 0;
}
/*
* si470x_set_register - write register
*/
int si470x_set_register(struct si470x_device *radio, int regnr)
{
int i;
u16 buf[WRITE_REG_NUM];
struct i2c_msg msgs[1] = {
{ radio->client->addr, 0, sizeof(u16) * WRITE_REG_NUM,
(void *)buf },
};
for (i = 0; i < WRITE_REG_NUM; i++)
buf[i] = __cpu_to_be16(radio->registers[WRITE_INDEX(i)]);
if (i2c_transfer(radio->client->adapter, msgs, 1) != 1)
return -EIO;
return 0;
}
/**************************************************************************
* General Driver Functions - ENTIRE REGISTERS
**************************************************************************/
/*
* si470x_get_all_registers - read entire registers
*/
static int si470x_get_all_registers(struct si470x_device *radio)
{
int i;
u16 buf[READ_REG_NUM];
struct i2c_msg msgs[1] = {
{ radio->client->addr, I2C_M_RD, sizeof(u16) * READ_REG_NUM,
(void *)buf },
};
if (i2c_transfer(radio->client->adapter, msgs, 1) != 1)
return -EIO;
for (i = 0; i < READ_REG_NUM; i++)
radio->registers[i] = __be16_to_cpu(buf[READ_INDEX(i)]);
return 0;
}
/**************************************************************************
* General Driver Functions - DISCONNECT_CHECK
**************************************************************************/
/*
* si470x_disconnect_check - check whether radio disconnects
*/
int si470x_disconnect_check(struct si470x_device *radio)
{
return 0;
}
/**************************************************************************
* File Operations Interface
**************************************************************************/
/*
* si470x_fops_open - file open
*/
int si470x_fops_open(struct file *file)
{
struct si470x_device *radio = video_drvdata(file);
int retval = 0;
mutex_lock(&radio->lock);
radio->users++;
if (radio->users == 1) {
/* start radio */
retval = si470x_start(radio);
if (retval < 0)
goto done;
/* enable RDS interrupt */
radio->registers[SYSCONFIG1] |= SYSCONFIG1_RDSIEN;
radio->registers[SYSCONFIG1] &= ~SYSCONFIG1_GPIO2;
radio->registers[SYSCONFIG1] |= 0x1 << 2;
retval = si470x_set_register(radio, SYSCONFIG1);
}
done:
mutex_unlock(&radio->lock);
return retval;
}
/*
* si470x_fops_release - file release
*/
int si470x_fops_release(struct file *file)
{
struct si470x_device *radio = video_drvdata(file);
int retval = 0;
/* safety check */
if (!radio)
return -ENODEV;
mutex_lock(&radio->lock);
radio->users--;
if (radio->users == 0)
/* stop radio */
retval = si470x_stop(radio);
mutex_unlock(&radio->lock);
return retval;
}
/**************************************************************************
* Video4Linux Interface
**************************************************************************/
/*
* si470x_vidioc_querycap - query device capabilities
*/
int si470x_vidioc_querycap(struct file *file, void *priv,
struct v4l2_capability *capability)
{
strlcpy(capability->driver, DRIVER_NAME, sizeof(capability->driver));
strlcpy(capability->card, DRIVER_CARD, sizeof(capability->card));
capability->version = DRIVER_KERNEL_VERSION;
capability->capabilities = V4L2_CAP_HW_FREQ_SEEK |
V4L2_CAP_TUNER | V4L2_CAP_RADIO;
return 0;
}
/**************************************************************************
* I2C Interface
**************************************************************************/
/*
* si470x_i2c_interrupt_work - rds processing function
*/
static void si470x_i2c_interrupt_work(struct work_struct *work)
{
struct si470x_device *radio = container_of(work,
struct si470x_device, radio_work);
unsigned char regnr;
unsigned char blocknum;
unsigned short bler; /* rds block errors */
unsigned short rds;
unsigned char tmpbuf[3];
int retval = 0;
/* safety checks */
if ((radio->registers[SYSCONFIG1] & SYSCONFIG1_RDS) == 0)
return;
/* Update RDS registers */
for (regnr = 0; regnr < RDS_REGISTER_NUM; regnr++) {
retval = si470x_get_register(radio, STATUSRSSI + regnr);
if (retval < 0)
return;
}
/* get rds blocks */
if ((radio->registers[STATUSRSSI] & STATUSRSSI_RDSR) == 0)
/* No RDS group ready, better luck next time */
return;
for (blocknum = 0; blocknum < 4; blocknum++) {
switch (blocknum) {
default:
bler = (radio->registers[STATUSRSSI] &
STATUSRSSI_BLERA) >> 9;
rds = radio->registers[RDSA];
break;
case 1:
bler = (radio->registers[READCHAN] &
READCHAN_BLERB) >> 14;
rds = radio->registers[RDSB];
break;
case 2:
bler = (radio->registers[READCHAN] &
READCHAN_BLERC) >> 12;
rds = radio->registers[RDSC];
break;
case 3:
bler = (radio->registers[READCHAN] &
READCHAN_BLERD) >> 10;
rds = radio->registers[RDSD];
break;
};
/* Fill the V4L2 RDS buffer */
put_unaligned_le16(rds, &tmpbuf);
tmpbuf[2] = blocknum; /* offset name */
tmpbuf[2] |= blocknum << 3; /* received offset */
if (bler > max_rds_errors)
tmpbuf[2] |= 0x80; /* uncorrectable errors */
else if (bler > 0)
tmpbuf[2] |= 0x40; /* corrected error(s) */
/* copy RDS block to internal buffer */
memcpy(&radio->buffer[radio->wr_index], &tmpbuf, 3);
radio->wr_index += 3;
/* wrap write pointer */
if (radio->wr_index >= radio->buf_size)
radio->wr_index = 0;
/* check for overflow */
if (radio->wr_index == radio->rd_index) {
/* increment and wrap read pointer */
radio->rd_index += 3;
if (radio->rd_index >= radio->buf_size)
radio->rd_index = 0;
}
}
if (radio->wr_index != radio->rd_index)
wake_up_interruptible(&radio->read_queue);
}
/*
* si470x_i2c_interrupt - interrupt handler
*/
static irqreturn_t si470x_i2c_interrupt(int irq, void *dev_id)
{
struct si470x_device *radio = dev_id;
if (!work_pending(&radio->radio_work))
schedule_work(&radio->radio_work);
return IRQ_HANDLED;
}
/*
* si470x_i2c_probe - probe for the device
*/
static int __devinit si470x_i2c_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct si470x_device *radio;
int retval = 0;
unsigned char version_warning = 0;
/* private data allocation and initialization */
radio = kzalloc(sizeof(struct si470x_device), GFP_KERNEL);
if (!radio) {
retval = -ENOMEM;
goto err_initial;
}
INIT_WORK(&radio->radio_work, si470x_i2c_interrupt_work);
radio->users = 0;
radio->client = client;
mutex_init(&radio->lock);
/* video device allocation and initialization */
radio->videodev = video_device_alloc();
if (!radio->videodev) {
retval = -ENOMEM;
goto err_radio;
}
memcpy(radio->videodev, &si470x_viddev_template,
sizeof(si470x_viddev_template));
video_set_drvdata(radio->videodev, radio);
/* power up : need 110ms */
radio->registers[POWERCFG] = POWERCFG_ENABLE;
if (si470x_set_register(radio, POWERCFG) < 0) {
retval = -EIO;
goto err_video;
}
msleep(110);
/* get device and chip versions */
if (si470x_get_all_registers(radio) < 0) {
retval = -EIO;
goto err_video;
}
dev_info(&client->dev, "DeviceID=0x%4.4hx ChipID=0x%4.4hx\n",
radio->registers[DEVICEID], radio->registers[CHIPID]);
if ((radio->registers[CHIPID] & CHIPID_FIRMWARE) < RADIO_FW_VERSION) {
dev_warn(&client->dev,
"This driver is known to work with "
"firmware version %hu,\n", RADIO_FW_VERSION);
dev_warn(&client->dev,
"but the device has firmware version %hu.\n",
radio->registers[CHIPID] & CHIPID_FIRMWARE);
version_warning = 1;
}
/* give out version warning */
if (version_warning == 1) {
dev_warn(&client->dev,
"If you have some trouble using this driver,\n");
dev_warn(&client->dev,
"please report to V4L ML at "
"linux-media@vger.kernel.org\n");
}
/* set initial frequency */
si470x_set_freq(radio, 87.5 * FREQ_MUL); /* available in all regions */
/* rds buffer allocation */
radio->buf_size = rds_buf * 3;
radio->buffer = kmalloc(radio->buf_size, GFP_KERNEL);
if (!radio->buffer) {
retval = -EIO;
goto err_video;
}
/* rds buffer configuration */
radio->wr_index = 0;
radio->rd_index = 0;
init_waitqueue_head(&radio->read_queue);
retval = request_irq(client->irq, si470x_i2c_interrupt,
IRQF_TRIGGER_FALLING, DRIVER_NAME, radio);
if (retval) {
dev_err(&client->dev, "Failed to register interrupt\n");
goto err_rds;
}
/* register video device */
retval = video_register_device(radio->videodev, VFL_TYPE_RADIO,
radio_nr);
if (retval) {
dev_warn(&client->dev, "Could not register video device\n");
goto err_all;
}
i2c_set_clientdata(client, radio);
return 0;
err_all:
free_irq(client->irq, radio);
err_rds:
kfree(radio->buffer);
err_video:
video_device_release(radio->videodev);
err_radio:
kfree(radio);
err_initial:
return retval;
}
/*
* si470x_i2c_remove - remove the device
*/
static __devexit int si470x_i2c_remove(struct i2c_client *client)
{
struct si470x_device *radio = i2c_get_clientdata(client);
free_irq(client->irq, radio);
cancel_work_sync(&radio->radio_work);
video_unregister_device(radio->videodev);
kfree(radio);
return 0;
}
#ifdef CONFIG_PM
/*
* si470x_i2c_suspend - suspend the device
*/
static int si470x_i2c_suspend(struct i2c_client *client, pm_message_t mesg)
{
struct si470x_device *radio = i2c_get_clientdata(client);
/* power down */
radio->registers[POWERCFG] |= POWERCFG_DISABLE;
if (si470x_set_register(radio, POWERCFG) < 0)
return -EIO;
return 0;
}
/*
* si470x_i2c_resume - resume the device
*/
static int si470x_i2c_resume(struct i2c_client *client)
{
struct si470x_device *radio = i2c_get_clientdata(client);
/* power up : need 110ms */
radio->registers[POWERCFG] |= POWERCFG_ENABLE;
if (si470x_set_register(radio, POWERCFG) < 0)
return -EIO;
msleep(110);
return 0;
}
#else
#define si470x_i2c_suspend NULL
#define si470x_i2c_resume NULL
#endif
/*
* si470x_i2c_driver - i2c driver interface
*/
static struct i2c_driver si470x_i2c_driver = {
.driver = {
.name = "si470x",
.owner = THIS_MODULE,
},
.probe = si470x_i2c_probe,
.remove = __devexit_p(si470x_i2c_remove),
.suspend = si470x_i2c_suspend,
.resume = si470x_i2c_resume,
.id_table = si470x_i2c_id,
};
/**************************************************************************
* Module Interface
**************************************************************************/
/*
* si470x_i2c_init - module init
*/
static int __init si470x_i2c_init(void)
{
printk(KERN_INFO DRIVER_DESC ", Version " DRIVER_VERSION "\n");
return i2c_add_driver(&si470x_i2c_driver);
}
/*
* si470x_i2c_exit - module exit
*/
static void __exit si470x_i2c_exit(void)
{
i2c_del_driver(&si470x_i2c_driver);
}
module_init(si470x_i2c_init);
module_exit(si470x_i2c_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_VERSION(DRIVER_VERSION);
