aboutsummaryrefslogtreecommitdiff
path: root/drivers/media/radio/si470x/radio-si470x-i2c.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/media/radio/si470x/radio-si470x-i2c.c')
-rw-r--r--drivers/media/radio/si470x/radio-si470x-i2c.c254
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");