diff options
Diffstat (limited to 'drivers/media/radio/si470x/radio-si470x-i2c.c')
| -rw-r--r-- | drivers/media/radio/si470x/radio-si470x-i2c.c | 254 |
1 files changed, 254 insertions, 0 deletions
diff --git a/drivers/media/radio/si470x/radio-si470x-i2c.c b/drivers/media/radio/si470x/radio-si470x-i2c.c new file mode 100644 index 00000000000..21810218470 --- /dev/null +++ b/drivers/media/radio/si470x/radio-si470x-i2c.c @@ -0,0 +1,254 @@ +/* + * 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. + * + * + * TODO: + * - RDS support + * + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/i2c.h> +#include <linux/delay.h> + +#include "radio-si470x.h" + +#define DRIVER_KERNEL_VERSION KERNEL_VERSION(1, 0, 0) +#define DRIVER_CARD "Silicon Labs Si470x FM Radio Receiver" +#define DRIVER_VERSION "1.0.0" + +/* starting 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) + +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; +} + +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; +} + +/* starting with the upper byte of register 0x02h */ +#define WRITE_REG_NUM 8 +#define WRITE_INDEX(i) (i + 0x02) + +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; +} + +int si470x_disconnect_check(struct si470x_device *radio) +{ + return 0; +} + +static 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); + mutex_unlock(&radio->lock); + + return retval; +} + +static 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; +} + +const struct v4l2_file_operations si470x_fops = { + .owner = THIS_MODULE, + .ioctl = video_ioctl2, + .open = si470x_fops_open, + .release = si470x_fops_release, +}; + +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; +} + +static int __devinit si470x_i2c_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct si470x_device *radio; + int retval = 0; + + /* private data allocation and initialization */ + radio = kzalloc(sizeof(struct si470x_device), GFP_KERNEL); + if (!radio) { + retval = -ENOMEM; + goto err_initial; + } + radio->client = client; + radio->users = 0; + 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_all; + } + msleep(110); + + /* show some infos about the specific si470x device */ + if (si470x_get_all_registers(radio) < 0) { + retval = -EIO; + goto err_radio; + } + dev_info(&client->dev, "DeviceID=0x%4.4hx ChipID=0x%4.4hx\n", + radio->registers[DEVICEID], radio->registers[CHIPID]); + + /* set initial frequency */ + si470x_set_freq(radio, 87.5 * FREQ_MUL); /* available in all regions */ + + /* register video device */ + retval = video_register_device(radio->videodev, VFL_TYPE_RADIO, -1); + if (retval) { + dev_warn(&client->dev, "Could not register video device\n"); + goto err_all; + } + + i2c_set_clientdata(client, radio); + + return 0; +err_all: + video_device_release(radio->videodev); +err_radio: + kfree(radio); +err_initial: + return retval; +} + +static __devexit int si470x_i2c_remove(struct i2c_client *client) +{ + struct si470x_device *radio = i2c_get_clientdata(client); + + video_unregister_device(radio->videodev); + kfree(radio); + i2c_set_clientdata(client, NULL); + + return 0; +} + +static const struct i2c_device_id si470x_i2c_id[] = { + { "si470x", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, si470x_i2c_id); + +static struct i2c_driver si470x_i2c_driver = { + .driver = { + .name = "si470x", + .owner = THIS_MODULE, + }, + .probe = si470x_i2c_probe, + .remove = __devexit_p(si470x_i2c_remove), + .id_table = si470x_i2c_id, +}; + +static int __init si470x_i2c_init(void) +{ + return i2c_add_driver(&si470x_i2c_driver); +} +module_init(si470x_i2c_init); + +static void __exit si470x_i2c_exit(void) +{ + i2c_del_driver(&si470x_i2c_driver); +} +module_exit(si470x_i2c_exit); + +MODULE_DESCRIPTION("i2c radio driver for si470x fm radio receivers"); +MODULE_AUTHOR("Joonyoung Shim <jy0922.shim@samsung.com>"); +MODULE_LICENSE("GPL"); |