1 files changed, 988 insertions, 0 deletions

diff --git a/drivers/media/radio/si470x/radio-si470x-usb.c b/drivers/media/radio/si470x/radio-si470x-usb.c
new file mode 100644
index 000000000000..f2d0e1ddb301
--- /dev/null
+++ b/drivers/media/radio/si470x/radio-si470x-usb.c
@@ -0,0 +1,988 @@
+/*
+ *  drivers/media/radio/si470x/radio-si470x-usb.c
+ *
+ *  USB driver for radios with Silicon Labs Si470x FM Radio Receivers
+ *
+ *  Copyright (c) 2009 Tobias Lorenz <tobias.lorenz@gmx.net>
+ *
+ * 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
+ */
+
+
+/*
+ * ToDo:
+ * - add firmware download/update support
+ */
+
+
+/* driver definitions */
+#define DRIVER_AUTHOR "Tobias Lorenz <tobias.lorenz@gmx.net>"
+#define DRIVER_KERNEL_VERSION KERNEL_VERSION(1, 0, 10)
+#define DRIVER_CARD "Silicon Labs Si470x FM Radio Receiver"
+#define DRIVER_DESC "USB radio driver for Si470x FM Radio Receivers"
+#define DRIVER_VERSION "1.0.10"
+
+/* kernel includes */
+#include <linux/usb.h>
+#include <linux/hid.h>
+
+#include "radio-si470x.h"
+
+
+/* USB Device ID List */
+static struct usb_device_id si470x_usb_driver_id_table[] = {
+        /* Silicon Labs USB FM Radio Reference Design */
+        { USB_DEVICE_AND_INTERFACE_INFO(0x10c4, 0x818a, USB_CLASS_HID, 0, 0) },
+        /* ADS/Tech FM Radio Receiver (formerly Instant FM Music) */
+        { USB_DEVICE_AND_INTERFACE_INFO(0x06e1, 0xa155, USB_CLASS_HID, 0, 0) },
+        /* KWorld USB FM Radio SnapMusic Mobile 700 (FM700) */
+        { USB_DEVICE_AND_INTERFACE_INFO(0x1b80, 0xd700, USB_CLASS_HID, 0, 0) },
+        /* Sanei Electric, Inc. FM USB Radio (sold as DealExtreme.com PCear) */
+        { USB_DEVICE_AND_INTERFACE_INFO(0x10c5, 0x819a, USB_CLASS_HID, 0, 0) },
+        /* Terminating entry */
+        { }
+};
+MODULE_DEVICE_TABLE(usb, si470x_usb_driver_id_table);
+
+
+
+/**************************************************************************
+ * Module Parameters
+ **************************************************************************/
+
+/* Radio Nr */
+static int radio_nr = -1;
+module_param(radio_nr, int, 0444);
+MODULE_PARM_DESC(radio_nr, "Radio Nr");
+
+/* USB timeout */
+static unsigned int usb_timeout = 500;
+module_param(usb_timeout, uint, 0644);
+MODULE_PARM_DESC(usb_timeout, "USB timeout (ms): *500*");
+
+/* 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*");
+
+
+
+/**************************************************************************
+ * USB HID Reports
+ **************************************************************************/
+
+/* Reports 1-16 give direct read/write access to the 16 Si470x registers */
+/* with the (REPORT_ID - 1) corresponding to the register address across USB */
+/* endpoint 0 using GET_REPORT and SET_REPORT */
+#define REGISTER_REPORT_SIZE    (RADIO_REGISTER_SIZE + 1)
+#define REGISTER_REPORT(reg)    ((reg) + 1)
+
+/* Report 17 gives direct read/write access to the entire Si470x register */
+/* map across endpoint 0 using GET_REPORT and SET_REPORT */
+#define ENTIRE_REPORT_SIZE      (RADIO_REGISTER_NUM * RADIO_REGISTER_SIZE + 1)
+#define ENTIRE_REPORT           17
+
+/* Report 18 is used to send the lowest 6 Si470x registers up the HID */
+/* interrupt endpoint 1 to Windows every 20 milliseconds for status */
+#define RDS_REPORT_SIZE         (RDS_REGISTER_NUM * RADIO_REGISTER_SIZE + 1)
+#define RDS_REPORT              18
+
+/* Report 19: LED state */
+#define LED_REPORT_SIZE         3
+#define LED_REPORT              19
+
+/* Report 19: stream */
+#define STREAM_REPORT_SIZE      3
+#define STREAM_REPORT           19
+
+/* Report 20: scratch */
+#define SCRATCH_PAGE_SIZE       63
+#define SCRATCH_REPORT_SIZE     (SCRATCH_PAGE_SIZE + 1)
+#define SCRATCH_REPORT          20
+
+/* Reports 19-22: flash upgrade of the C8051F321 */
+#define WRITE_REPORT_SIZE       4
+#define WRITE_REPORT            19
+#define FLASH_REPORT_SIZE       64
+#define FLASH_REPORT            20
+#define CRC_REPORT_SIZE         3
+#define CRC_REPORT              21
+#define RESPONSE_REPORT_SIZE    2
+#define RESPONSE_REPORT         22
+
+/* Report 23: currently unused, but can accept 60 byte reports on the HID */
+/* interrupt out endpoint 2 every 1 millisecond */
+#define UNUSED_REPORT           23
+
+
+
+/**************************************************************************
+ * Software/Hardware Versions from Scratch Page
+ **************************************************************************/
+#define RADIO_SW_VERSION_NOT_BOOTLOADABLE       6
+#define RADIO_SW_VERSION                        7
+#define RADIO_HW_VERSION                        1
+
+
+
+/**************************************************************************
+ * LED State Definitions
+ **************************************************************************/
+#define LED_COMMAND             0x35
+
+#define NO_CHANGE_LED           0x00
+#define ALL_COLOR_LED           0x01    /* streaming state */
+#define BLINK_GREEN_LED         0x02    /* connect state */
+#define BLINK_RED_LED           0x04
+#define BLINK_ORANGE_LED        0x10    /* disconnect state */
+#define SOLID_GREEN_LED         0x20    /* tuning/seeking state */
+#define SOLID_RED_LED           0x40    /* bootload state */
+#define SOLID_ORANGE_LED        0x80
+
+
+
+/**************************************************************************
+ * Stream State Definitions
+ **************************************************************************/
+#define STREAM_COMMAND  0x36
+#define STREAM_VIDPID   0x00
+#define STREAM_AUDIO    0xff
+
+
+
+/**************************************************************************
+ * Bootloader / Flash Commands
+ **************************************************************************/
+
+/* unique id sent to bootloader and required to put into a bootload state */
+#define UNIQUE_BL_ID            0x34
+
+/* mask for the flash data */
+#define FLASH_DATA_MASK         0x55
+
+/* bootloader commands */
+#define GET_SW_VERSION_COMMAND  0x00
+#define SET_PAGE_COMMAND        0x01
+#define ERASE_PAGE_COMMAND      0x02
+#define WRITE_PAGE_COMMAND      0x03
+#define CRC_ON_PAGE_COMMAND     0x04
+#define READ_FLASH_BYTE_COMMAND 0x05
+#define RESET_DEVICE_COMMAND    0x06
+#define GET_HW_VERSION_COMMAND  0x07
+#define BLANK                   0xff
+
+/* bootloader command responses */
+#define COMMAND_OK              0x01
+#define COMMAND_FAILED          0x02
+#define COMMAND_PENDING         0x03
+
+
+
+/**************************************************************************
+ * General Driver Functions - REGISTER_REPORTs
+ **************************************************************************/
+
+/*
+ * si470x_get_report - receive a HID report
+ */
+static int si470x_get_report(struct si470x_device *radio, void *buf, int size)
+{
+        unsigned char *report = (unsigned char *) buf;
+        int retval;
+
+        retval = usb_control_msg(radio->usbdev,
+                usb_rcvctrlpipe(radio->usbdev, 0),
+                HID_REQ_GET_REPORT,
+                USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
+                report[0], 2,
+                buf, size, usb_timeout);
+
+        if (retval < 0)
+                dev_warn(&radio->intf->dev,
+                        "si470x_get_report: usb_control_msg returned %d\n",
+                        retval);
+        return retval;
+}
+
+
+/*
+ * si470x_set_report - send a HID report
+ */
+static int si470x_set_report(struct si470x_device *radio, void *buf, int size)
+{
+        unsigned char *report = (unsigned char *) buf;
+        int retval;
+
+        retval = usb_control_msg(radio->usbdev,
+                usb_sndctrlpipe(radio->usbdev, 0),
+                HID_REQ_SET_REPORT,
+                USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
+                report[0], 2,
+                buf, size, usb_timeout);
+
+        if (retval < 0)
+                dev_warn(&radio->intf->dev,
+                        "si470x_set_report: usb_control_msg returned %d\n",
+                        retval);
+        return retval;
+}
+
+
+/*
+ * si470x_get_register - read register
+ */
+int si470x_get_register(struct si470x_device *radio, int regnr)
+{
+        unsigned char buf[REGISTER_REPORT_SIZE];
+        int retval;
+
+        buf[0] = REGISTER_REPORT(regnr);
+
+        retval = si470x_get_report(radio, (void *) &buf, sizeof(buf));
+
+        if (retval >= 0)
+                radio->registers[regnr] = get_unaligned_be16(&buf[1]);
+
+        return (retval < 0) ? -EINVAL : 0;
+}
+
+
+/*
+ * si470x_set_register - write register
+ */
+int si470x_set_register(struct si470x_device *radio, int regnr)
+{
+        unsigned char buf[REGISTER_REPORT_SIZE];
+        int retval;
+
+        buf[0] = REGISTER_REPORT(regnr);
+        put_unaligned_be16(radio->registers[regnr], &buf[1]);
+
+        retval = si470x_set_report(radio, (void *) &buf, sizeof(buf));
+
+        return (retval < 0) ? -EINVAL : 0;
+}
+
+
+
+/**************************************************************************
+ * General Driver Functions - ENTIRE_REPORT
+ **************************************************************************/
+
+/*
+ * si470x_get_all_registers - read entire registers
+ */
+static int si470x_get_all_registers(struct si470x_device *radio)
+{
+        unsigned char buf[ENTIRE_REPORT_SIZE];
+        int retval;
+        unsigned char regnr;
+
+        buf[0] = ENTIRE_REPORT;
+
+        retval = si470x_get_report(radio, (void *) &buf, sizeof(buf));
+
+        if (retval >= 0)
+                for (regnr = 0; regnr < RADIO_REGISTER_NUM; regnr++)
+                        radio->registers[regnr] = get_unaligned_be16(
+                                &buf[regnr * RADIO_REGISTER_SIZE + 1]);
+
+        return (retval < 0) ? -EINVAL : 0;
+}
+
+
+
+/**************************************************************************
+ * General Driver Functions - LED_REPORT
+ **************************************************************************/
+
+/*
+ * si470x_set_led_state - sets the led state
+ */
+static int si470x_set_led_state(struct si470x_device *radio,
+                unsigned char led_state)
+{
+        unsigned char buf[LED_REPORT_SIZE];
+        int retval;
+
+        buf[0] = LED_REPORT;
+        buf[1] = LED_COMMAND;
+        buf[2] = led_state;
+
+        retval = si470x_set_report(radio, (void *) &buf, sizeof(buf));
+
+        return (retval < 0) ? -EINVAL : 0;
+}
+
+
+
+/**************************************************************************
+ * General Driver Functions - SCRATCH_REPORT
+ **************************************************************************/
+
+/*
+ * si470x_get_scratch_versions - gets the scratch page and version infos
+ */
+static int si470x_get_scratch_page_versions(struct si470x_device *radio)
+{
+        unsigned char buf[SCRATCH_REPORT_SIZE];
+        int retval;
+
+        buf[0] = SCRATCH_REPORT;
+
+        retval = si470x_get_report(radio, (void *) &buf, sizeof(buf));
+
+        if (retval < 0)
+                dev_warn(&radio->intf->dev, "si470x_get_scratch: "
+                        "si470x_get_report returned %d\n", retval);
+        else {
+                radio->software_version = buf[1];
+                radio->hardware_version = buf[2];
+        }
+
+        return (retval < 0) ? -EINVAL : 0;
+}
+
+
+
+/**************************************************************************
+ * General Driver Functions - DISCONNECT_CHECK
+ **************************************************************************/
+
+/*
+ * si470x_disconnect_check - check whether radio disconnects
+ */
+int si470x_disconnect_check(struct si470x_device *radio)
+{
+        if (radio->disconnected)
+                return -EIO;
+        else
+                return 0;
+}
+
+
+
+/**************************************************************************
+ * RDS Driver Functions
+ **************************************************************************/
+
+/*
+ * si470x_int_in_callback - rds callback and processing function
+ *
+ * TODO: do we need to use mutex locks in some sections?
+ */
+static void si470x_int_in_callback(struct urb *urb)
+{
+        struct si470x_device *radio = urb->context;
+        unsigned char buf[RDS_REPORT_SIZE];
+        int retval;
+        unsigned char regnr;
+        unsigned char blocknum;
+        unsigned short bler; /* rds block errors */
+        unsigned short rds;
+        unsigned char tmpbuf[3];
+
+        if (urb->status) {
+                if (urb->status == -ENOENT ||
+                                urb->status == -ECONNRESET ||
+                                urb->status == -ESHUTDOWN) {
+                        return;
+                } else {
+                        dev_warn(&radio->intf->dev,
+                         "non-zero urb status (%d)\n", urb->status);
+                        goto resubmit; /* Maybe we can recover. */
+                }
+        }
+
+        /* safety checks */
+        if (radio->disconnected)
+                return;
+        if ((radio->registers[SYSCONFIG1] & SYSCONFIG1_RDS) == 0)
+                goto resubmit;
+
+        if (urb->actual_length > 0) {
+                /* Update RDS registers with URB data */
+                buf[0] = RDS_REPORT;
+                for (regnr = 0; regnr < RDS_REGISTER_NUM; regnr++)
+                        radio->registers[STATUSRSSI + regnr] =
+                            get_unaligned_be16(&radio->int_in_buffer[
+                                regnr * RADIO_REGISTER_SIZE + 1]);
+                /* get rds blocks */
+                if ((radio->registers[STATUSRSSI] & STATUSRSSI_RDSR) == 0) {
+                        /* No RDS group ready, better luck next time */
+                        goto resubmit;
+                }
+                if ((radio->registers[STATUSRSSI] & STATUSRSSI_RDSS) == 0) {
+                        /* RDS decoder not synchronized */
+                        goto resubmit;
+                }
+                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);
+        }
+
+resubmit:
+        /* Resubmit if we're still running. */
+        if (radio->int_in_running && radio->usbdev) {
+                retval = usb_submit_urb(radio->int_in_urb, GFP_ATOMIC);
+                if (retval) {
+                        dev_warn(&radio->intf->dev,
+                               "resubmitting urb failed (%d)", retval);
+                        radio->int_in_running = 0;
+                }
+        }
+}
+
+
+
+/**************************************************************************
+ * File Operations Interface
+ **************************************************************************/
+
+/*
+ * si470x_fops_read - read RDS data
+ */
+static ssize_t si470x_fops_read(struct file *file, char __user *buf,
+                size_t count, loff_t *ppos)
+{
+        struct si470x_device *radio = video_drvdata(file);
+        int retval = 0;
+        unsigned int block_count = 0;
+
+        /* switch on rds reception */
+        if ((radio->registers[SYSCONFIG1] & SYSCONFIG1_RDS) == 0)
+                si470x_rds_on(radio);
+
+        /* block if no new data available */
+        while (radio->wr_index == radio->rd_index) {
+                if (file->f_flags & O_NONBLOCK) {
+                        retval = -EWOULDBLOCK;
+                        goto done;
+                }
+                if (wait_event_interruptible(radio->read_queue,
+                        radio->wr_index != radio->rd_index) < 0) {
+                        retval = -EINTR;
+                        goto done;
+                }
+        }
+
+        /* calculate block count from byte count */
+        count /= 3;
+
+        /* copy RDS block out of internal buffer and to user buffer */
+        mutex_lock(&radio->lock);
+        while (block_count < count) {
+                if (radio->rd_index == radio->wr_index)
+                        break;
+
+                /* always transfer rds complete blocks */
+                if (copy_to_user(buf, &radio->buffer[radio->rd_index], 3))
+                        /* retval = -EFAULT; */
+                        break;
+
+                /* increment and wrap read pointer */
+                radio->rd_index += 3;
+                if (radio->rd_index >= radio->buf_size)
+                        radio->rd_index = 0;
+
+                /* increment counters */
+                block_count++;
+                buf += 3;
+                retval += 3;
+        }
+        mutex_unlock(&radio->lock);
+
+done:
+        return retval;
+}
+
+
+/*
+ * si470x_fops_poll - poll RDS data
+ */
+static unsigned int si470x_fops_poll(struct file *file,
+                struct poll_table_struct *pts)
+{
+        struct si470x_device *radio = video_drvdata(file);
+        int retval = 0;
+
+        /* switch on rds reception */
+        if ((radio->registers[SYSCONFIG1] & SYSCONFIG1_RDS) == 0)
+                si470x_rds_on(radio);
+
+        poll_wait(file, &radio->read_queue, pts);
+
+        if (radio->rd_index != radio->wr_index)
+                retval = POLLIN | POLLRDNORM;
+
+        return retval;
+}
+
+
+/*
+ * si470x_fops_open - file open
+ */
+static int si470x_fops_open(struct file *file)
+{
+        struct si470x_device *radio = video_drvdata(file);
+        int retval;
+
+        lock_kernel();
+        radio->users++;
+
+        retval = usb_autopm_get_interface(radio->intf);
+        if (retval < 0) {
+                radio->users--;
+                retval = -EIO;
+                goto done;
+        }
+
+        if (radio->users == 1) {
+                /* start radio */
+                retval = si470x_start(radio);
+                if (retval < 0) {
+                        usb_autopm_put_interface(radio->intf);
+                        goto done;
+                }
+
+                /* initialize interrupt urb */
+                usb_fill_int_urb(radio->int_in_urb, radio->usbdev,
+                        usb_rcvintpipe(radio->usbdev,
+                        radio->int_in_endpoint->bEndpointAddress),
+                        radio->int_in_buffer,
+                        le16_to_cpu(radio->int_in_endpoint->wMaxPacketSize),
+                        si470x_int_in_callback,
+                        radio,
+                        radio->int_in_endpoint->bInterval);
+
+                radio->int_in_running = 1;
+                mb();
+
+                retval = usb_submit_urb(radio->int_in_urb, GFP_KERNEL);
+                if (retval) {
+                        dev_info(&radio->intf->dev,
+                                 "submitting int urb failed (%d)\n", retval);
+                        radio->int_in_running = 0;
+                        usb_autopm_put_interface(radio->intf);
+                }
+        }
+
+done:
+        unlock_kernel();
+        return retval;
+}
+
+
+/*
+ * si470x_fops_release - file release
+ */
+static int si470x_fops_release(struct file *file)
+{
+        struct si470x_device *radio = video_drvdata(file);
+        int retval = 0;
+
+        /* safety check */
+        if (!radio) {
+                retval = -ENODEV;
+                goto done;
+        }
+
+        mutex_lock(&radio->disconnect_lock);
+        radio->users--;
+        if (radio->users == 0) {
+                /* shutdown interrupt handler */
+                if (radio->int_in_running) {
+                        radio->int_in_running = 0;
+                if (radio->int_in_urb)
+                        usb_kill_urb(radio->int_in_urb);
+                }
+
+                if (radio->disconnected) {
+                        video_unregister_device(radio->videodev);
+                        kfree(radio->int_in_buffer);
+                        kfree(radio->buffer);
+                        kfree(radio);
+                        goto unlock;
+                }
+
+                /* cancel read processes */
+                wake_up_interruptible(&radio->read_queue);
+
+                /* stop radio */
+                retval = si470x_stop(radio);
+                usb_autopm_put_interface(radio->intf);
+        }
+unlock:
+        mutex_unlock(&radio->disconnect_lock);
+done:
+        return retval;
+}
+
+
+/*
+ * si470x_fops - file operations interface
+ */
+const struct v4l2_file_operations si470x_fops = {
+        .owner          = THIS_MODULE,
+        .read           = si470x_fops_read,
+        .poll           = si470x_fops_poll,
+        .ioctl          = video_ioctl2,
+        .open           = si470x_fops_open,
+        .release        = si470x_fops_release,
+};
+
+
+
+/**************************************************************************
+ * Video4Linux Interface
+ **************************************************************************/
+
+/*
+ * si470x_vidioc_querycap - query device capabilities
+ */
+int si470x_vidioc_querycap(struct file *file, void *priv,
+                struct v4l2_capability *capability)
+{
+        struct si470x_device *radio = video_drvdata(file);
+
+        strlcpy(capability->driver, DRIVER_NAME, sizeof(capability->driver));
+        strlcpy(capability->card, DRIVER_CARD, sizeof(capability->card));
+        usb_make_path(radio->usbdev, capability->bus_info,
+                        sizeof(capability->bus_info));
+        capability->version = DRIVER_KERNEL_VERSION;
+        capability->capabilities = V4L2_CAP_HW_FREQ_SEEK |
+                V4L2_CAP_TUNER | V4L2_CAP_RADIO | V4L2_CAP_RDS_CAPTURE;
+
+        return 0;
+}
+
+
+
+/**************************************************************************
+ * USB Interface
+ **************************************************************************/
+
+/*
+ * si470x_usb_driver_probe - probe for the device
+ */
+static int si470x_usb_driver_probe(struct usb_interface *intf,
+                const struct usb_device_id *id)
+{
+        struct si470x_device *radio;
+        struct usb_host_interface *iface_desc;
+        struct usb_endpoint_descriptor *endpoint;
+        int i, int_end_size, 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;
+        }
+        radio->users = 0;
+        radio->disconnected = 0;
+        radio->usbdev = interface_to_usbdev(intf);
+        radio->intf = intf;
+        mutex_init(&radio->disconnect_lock);
+        mutex_init(&radio->lock);
+
+        iface_desc = intf->cur_altsetting;
+
+        /* Set up interrupt endpoint information. */
+        for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
+                endpoint = &iface_desc->endpoint[i].desc;
+                if (((endpoint->bEndpointAddress & USB_ENDPOINT_DIR_MASK) ==
+                 USB_DIR_IN) && ((endpoint->bmAttributes &
+                 USB_ENDPOINT_XFERTYPE_MASK) == USB_ENDPOINT_XFER_INT))
+                        radio->int_in_endpoint = endpoint;
+        }
+        if (!radio->int_in_endpoint) {
+                dev_info(&intf->dev, "could not find interrupt in endpoint\n");
+                retval = -EIO;
+                goto err_radio;
+        }
+
+        int_end_size = le16_to_cpu(radio->int_in_endpoint->wMaxPacketSize);
+
+        radio->int_in_buffer = kmalloc(int_end_size, GFP_KERNEL);
+        if (!radio->int_in_buffer) {
+                dev_info(&intf->dev, "could not allocate int_in_buffer");
+                retval = -ENOMEM;
+                goto err_radio;
+        }
+
+        radio->int_in_urb = usb_alloc_urb(0, GFP_KERNEL);
+        if (!radio->int_in_urb) {
+                dev_info(&intf->dev, "could not allocate int_in_urb");
+                retval = -ENOMEM;
+                goto err_intbuffer;
+        }
+
+        /* video device allocation and initialization */
+        radio->videodev = video_device_alloc();
+        if (!radio->videodev) {
+                retval = -ENOMEM;
+                goto err_intbuffer;
+        }
+        memcpy(radio->videodev, &si470x_viddev_template,
+                        sizeof(si470x_viddev_template));
+        video_set_drvdata(radio->videodev, radio);
+
+        /* get device and chip versions */
+        if (si470x_get_all_registers(radio) < 0) {
+                retval = -EIO;
+                goto err_video;
+        }
+        dev_info(&intf->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(&intf->dev,
+                        "This driver is known to work with "
+                        "firmware version %hu,\n", RADIO_FW_VERSION);
+                dev_warn(&intf->dev,
+                        "but the device has firmware version %hu.\n",
+                        radio->registers[CHIPID] & CHIPID_FIRMWARE);
+                version_warning = 1;
+        }
+
+        /* get software and hardware versions */
+        if (si470x_get_scratch_page_versions(radio) < 0) {
+                retval = -EIO;
+                goto err_video;
+        }
+        dev_info(&intf->dev, "software version %d, hardware version %d\n",
+                        radio->software_version, radio->hardware_version);
+        if (radio->software_version < RADIO_SW_VERSION) {
+                dev_warn(&intf->dev,
+                        "This driver is known to work with "
+                        "software version %hu,\n", RADIO_SW_VERSION);
+                dev_warn(&intf->dev,
+                        "but the device has software version %hu.\n",
+                        radio->software_version);
+                version_warning = 1;
+        }
+        if (radio->hardware_version < RADIO_HW_VERSION) {
+                dev_warn(&intf->dev,
+                        "This driver is known to work with "
+                        "hardware version %hu,\n", RADIO_HW_VERSION);
+                dev_warn(&intf->dev,
+                        "but the device has hardware version %hu.\n",
+                        radio->hardware_version);
+                version_warning = 1;
+        }
+
+        /* give out version warning */
+        if (version_warning == 1) {
+                dev_warn(&intf->dev,
+                        "If you have some trouble using this driver,\n");
+                dev_warn(&intf->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 */
+
+        /* set led to connect state */
+        si470x_set_led_state(radio, BLINK_GREEN_LED);
+
+        /* 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);
+
+        /* register video device */
+        retval = video_register_device(radio->videodev, VFL_TYPE_RADIO,
+                        radio_nr);
+        if (retval) {
+                dev_warn(&intf->dev, "Could not register video device\n");
+                goto err_all;
+        }
+        usb_set_intfdata(intf, radio);
+
+        return 0;
+err_all:
+        kfree(radio->buffer);
+err_video:
+        video_device_release(radio->videodev);
+err_intbuffer:
+        kfree(radio->int_in_buffer);
+err_radio:
+        kfree(radio);
+err_initial:
+        return retval;
+}
+
+
+/*
+ * si470x_usb_driver_suspend - suspend the device
+ */
+static int si470x_usb_driver_suspend(struct usb_interface *intf,
+                pm_message_t message)
+{
+        dev_info(&intf->dev, "suspending now...\n");
+
+        return 0;
+}
+
+
+/*
+ * si470x_usb_driver_resume - resume the device
+ */
+static int si470x_usb_driver_resume(struct usb_interface *intf)
+{
+        dev_info(&intf->dev, "resuming now...\n");
+
+        return 0;
+}
+
+
+/*
+ * si470x_usb_driver_disconnect - disconnect the device
+ */
+static void si470x_usb_driver_disconnect(struct usb_interface *intf)
+{
+        struct si470x_device *radio = usb_get_intfdata(intf);
+
+        mutex_lock(&radio->disconnect_lock);
+        radio->disconnected = 1;
+        usb_set_intfdata(intf, NULL);
+        if (radio->users == 0) {
+                /* set led to disconnect state */
+                si470x_set_led_state(radio, BLINK_ORANGE_LED);
+
+                /* Free data structures. */
+                usb_free_urb(radio->int_in_urb);
+
+                kfree(radio->int_in_buffer);
+                video_unregister_device(radio->videodev);
+                kfree(radio->buffer);
+                kfree(radio);
+        }
+        mutex_unlock(&radio->disconnect_lock);
+}
+
+
+/*
+ * si470x_usb_driver - usb driver interface
+ */
+static struct usb_driver si470x_usb_driver = {
+        .name                   = DRIVER_NAME,
+        .probe                  = si470x_usb_driver_probe,
+        .disconnect             = si470x_usb_driver_disconnect,
+        .suspend                = si470x_usb_driver_suspend,
+        .resume                 = si470x_usb_driver_resume,
+        .id_table               = si470x_usb_driver_id_table,
+        .supports_autosuspend   = 1,
+};
+
+
+
+/**************************************************************************
+ * Module Interface
+ **************************************************************************/
+
+/*
+ * si470x_module_init - module init
+ */
+static int __init si470x_module_init(void)
+{
+        printk(KERN_INFO DRIVER_DESC ", Version " DRIVER_VERSION "\n");
+        return usb_register(&si470x_usb_driver);
+}
+
+
+/*
+ * si470x_module_exit - module exit
+ */
+static void __exit si470x_module_exit(void)
+{
+        usb_deregister(&si470x_usb_driver);
+}
+
+
+module_init(si470x_module_init);
+module_exit(si470x_module_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_VERSION(DRIVER_VERSION);