/*
* Copyright (c) 2012 Hans Verkuil <hverkuil@xs4all.nl>
*
* 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
*/
/* kernel includes */
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/input.h>
#include <linux/videodev2.h>
#include <media/v4l2-device.h>
#include <media/v4l2-ioctl.h>
#include <media/v4l2-ctrls.h>
#include <media/v4l2-event.h>
#include <linux/usb.h>
#include <linux/mutex.h>
/* driver and module definitions */
MODULE_AUTHOR("Hans Verkuil <hverkuil@xs4all.nl>");
MODULE_DESCRIPTION("Keene FM Transmitter driver");
MODULE_LICENSE("GPL");
/* Actually, it advertises itself as a Logitech */
#define USB_KEENE_VENDOR 0x046d
#define USB_KEENE_PRODUCT 0x0a0e
/* Probably USB_TIMEOUT should be modified in module parameter */
#define BUFFER_LENGTH 8
#define USB_TIMEOUT 500
/* Frequency limits in MHz */
#define FREQ_MIN 76U
#define FREQ_MAX 108U
#define FREQ_MUL 16000U
/* USB Device ID List */
static struct usb_device_id usb_keene_device_table[] = {
{USB_DEVICE_AND_INTERFACE_INFO(USB_KEENE_VENDOR, USB_KEENE_PRODUCT,
USB_CLASS_HID, 0, 0) },
{ } /* Terminating entry */
};
MODULE_DEVICE_TABLE(usb, usb_keene_device_table);
struct keene_device {
struct usb_device *usbdev;
struct usb_interface *intf;
struct video_device vdev;
struct v4l2_device v4l2_dev;
struct v4l2_ctrl_handler hdl;
struct mutex lock;
u8 *buffer;
unsigned curfreq;
u8 tx;
u8 pa;
bool stereo;
bool muted;
bool preemph_75_us;
};
static inline struct keene_device *to_keene_dev(struct v4l2_device *v4l2_dev)
{
return container_of(v4l2_dev, struct keene_device, v4l2_dev);
}
/* Set frequency (if non-0), PA, mute and turn on/off the FM transmitter. */
static int keene_cmd_main(struct keene_device *radio, unsigned freq, bool play)
{
unsigned short freq_send = freq ? (freq - 76 * 16000) / 800 : 0;
int ret;
radio->buffer[0] = 0x00;
radio->buffer[1] = 0x50;
radio->buffer[2] = (freq_send >> 8) & 0xff;
radio->buffer[3] = freq_send & 0xff;
radio->buffer[4] = radio->pa;
/* If bit 4 is set, then tune to the frequency.
If bit 3 is set, then unmute; if bit 2 is set, then mute.
If bit 1 is set, then enter idle mode; if bit 0 is set,
then enter transmit mode.
*/
radio->buffer[5] = (radio->muted ? 4 : 8) | (play ? 1 : 2) |
(freq ? 0x10 : 0);
radio->buffer[6] = 0x00;
radio->buffer[7] = 0x00;
ret = usb_control_msg(radio->usbdev, usb_sndctrlpipe(radio->usbdev, 0),
9, 0x21, 0x200, 2, radio->buffer, BUFFER_LENGTH, USB_TIMEOUT);
if (ret < 0) {
dev_warn(&radio->vdev.dev, "%s failed (%d)\n", __func__, ret);
return ret;
}
if (freq)
radio->curfreq = freq;
return 0;
}
/* Set TX, stereo and preemphasis mode (50 us vs 75 us). */
static int keene_cmd_set(struct keene_device *radio)
{
int ret;
radio->buffer[0] = 0x00;
radio->buffer[1] = 0x51;
radio->buffer[2] = radio->tx;
/* If bit 0 is set, then transmit mono, otherwise stereo.
If bit 2 is set, then enable 75 us preemphasis, otherwise
it is 50 us. */
radio->buffer[3] = (radio->stereo ? 0 : 1) | (radio->preemph_75_us ? 4 : 0);
radio->buffer[4] = 0x00;
radio->buffer[5] = 0x00;
radio->buffer[6] = 0x00;
radio->buffer[7] = 0x00;
ret = usb_control_msg(radio->usbdev, usb_sndctrlpipe(radio->usbdev, 0),
9, 0x21, 0x200, 2, radio->buffer, BUFFER_LENGTH, USB_TIMEOUT);
if (ret < 0) {
dev_warn(&radio->vdev.dev, "%s failed (%d)\n", __func__, ret);
return ret;
}
return 0;
}
/* Handle unplugging the device.
* We call video_unregister_device in any case.
* The last function called in this procedure is
* usb_keene_device_release.
*/
static void usb_keene_disconnect(struct usb_interface *intf)
{
struct keene_device *radio = to_keene_dev(usb_get_intfdata(intf));
mutex_lock(&radio->lock);
usb_set_intfdata(intf, NULL);
video_unregister_device(&radio->vdev);
v4l2_device_disconnect(&radio->v4l2_dev);
mutex_unlock(&radio->lock);
v4l2_device_put(&radio->v4l2_dev);
}
static int usb_keene_suspend(struct usb_interface *intf, pm_message_t message)
{
struct keene_device *radio = to_keene_dev(usb_get_intfdata(intf));
return keene_cmd_main(radio, 0, false);
}
static int usb_keene_resume(struct usb_interface *intf)
{
struct keene_device *radio = to_keene_dev(usb_get_intfdata(intf));
mdelay(50);
keene_cmd_set(radio);
keene_cmd_main(radio, radio->curfreq, true);
return 0;
}
static int vidioc_querycap(struct file *file, void *priv,
struct v4l2_capability *v)
{
struct keene_device *radio = video_drvdata(file);
strlcpy(v->driver, "radio-keene", sizeof(v->driver));
strlcpy(v->card, "Keene FM Transmitter", sizeof(v->card));
usb_make_path(radio->usbdev, v->bus_info, sizeof(v->bus_info));
v->device_caps = V4L2_CAP_RADIO | V4L2_CAP_MODULATOR;
v->capabilities = v->device_caps | V4L2_CAP_DEVICE_CAPS;
return 0;
}
static int vidioc_g_modulator(struct file *file, void *priv,
struct v4l2_modulator *v)
{
struct keene_device *radio = video_drvdata(file);
if (v->index > 0)
return -EINVAL;
strlcpy(v->name, "FM", sizeof(v->name));
v->rangelow = FREQ_MIN * FREQ_MUL;
v->rangehigh = FREQ_MAX * FREQ_MUL;
v->txsubchans = radio->stereo ? V4L2_TUNER_SUB_STEREO : V4L2_TUNER_SUB_MONO;
v->capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_STEREO;
return 0;
}
static int vidioc_s_modulator(struct file *file, void *priv,
const struct v4l2_modulator *v)
{
struct keene_device *radio = video_drvdata(file);
if (v->index > 0)
return -EINVAL;
radio->stereo = (v->txsubchans == V4L2_TUNER_SUB_STEREO);
return keene_cmd_set(radio);
}
static int vidioc_s_frequency(struct file *file, void *priv,
const struct v4l2_frequency *f)
{
struct keene_device *radio = video_drvdata(file);
unsigned freq = f->frequency;
if (f->tuner != 0 || f->type != V4L2_TUNER_RADIO)
return -EINVAL;
freq = clamp(freq, FREQ_MIN * FREQ_MUL, FREQ_MAX * FREQ_MUL);
return keene_cmd_main(radio, freq, true);
}
static int vidioc_g_frequency(struct file *file, void *priv,
struct v4l2_frequency *f)
{
struct keene_device *radio = video_drvdata(file);
if (f->tuner != 0)
return -EINVAL;
f->type = V4L2_TUNER_RADIO;
f->frequency = radio->curfreq;
return 0;
}
static int keene_s_ctrl(struct v4l2_ctrl *ctrl)
{
static const u8 db2tx[] = {
/* -15, -12, -9, -6, -3, 0 dB */
0x03, 0x13, 0x02, 0x12, 0x22, 0x32,
/* 3, 6, 9, 12, 15, 18 dB */
0x21, 0x31, 0x20, 0x30, 0x40, 0x50
};
struct keene_device *radio =
container_of(ctrl->handler, struct keene_device, hdl);
switch (ctrl->id) {
case V4L2_CID_AUDIO_MUTE:
radio->muted = ctrl->val;
return keene_cmd_main(radio, 0, true);
case V4L2_CID_TUNE_POWER_LEVEL:
/* To go from dBuV to the register value we apply the
following formula: */
radio->pa = (ctrl->val - 71) * 100 / 62;
return keene_cmd_main(radio, 0, true);
case V4L2_CID_TUNE_PREEMPHASIS:
radio->preemph_75_us = ctrl->val == V4L2_PREEMPHASIS_75_uS;
return keene_cmd_set(radio);
case V4L2_CID_AUDIO_COMPRESSION_GAIN:
radio->tx = db2tx[(ctrl->val - (s32)ctrl->minimum) / (s32)ctrl->step];
return keene_cmd_set(radio);
}
return -EINVAL;
}
/* File system interface */
static const struct v4l2_file_operations usb_keene_fops = {
.owner = THIS_MODULE,
.open = v4l2_fh_open,
.release = v4l2_fh_release,
.poll = v4l2_ctrl_poll,
.unlocked_ioctl = video_ioctl2,
};
static const struct v4l2_ctrl_ops keene_ctrl_ops = {
.s_ctrl = keene_s_ctrl,
};
static const struct v4l2_ioctl_ops usb_keene_ioctl_ops = {
.vidioc_querycap = vidioc_querycap,
.vidioc_g_modulator = vidioc_g_modulator,
.vidioc_s_modulator = vidioc_s_modulator,
.vidioc_g_frequency = vidioc_g_frequency,
.vidioc_s_frequency = vidioc_s_frequency,
.vidioc_log_status = v4l2_ctrl_log_status,
.vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
.vidioc_unsubscribe_event = v4l2_event_unsubscribe,
};
static void usb_keene_video_device_release(struct v4l2_device *v4l2_dev)
{
struct keene_device *radio = to_keene_dev(v4l2_dev);
/* free rest memory */
v4l2_ctrl_handler_free(&radio->hdl);
kfree(radio->buffer);
kfree(radio);
}
/* check if the device is present and register with v4l and usb if it is */
static int usb_keene_probe(struct usb_interface *intf,
const struct usb_device_id *id)
{
struct usb_device *dev = interface_to_usbdev(intf);
struct keene_device *radio;
struct v4l2_ctrl_handler *hdl;
int retval = 0;
/*
* The Keene FM transmitter USB device has the same USB ID as
* the Logitech AudioHub Speaker, but it should ignore the hid.
* Check if the name is that of the Keene device.
* If not, then someone connected the AudioHub and we shouldn't
* attempt to handle this driver.
* For reference: the product name of the AudioHub is
* "AudioHub Speaker".
*/
if (dev->product && strcmp(dev->product, "B-LINK USB Audio "))
return -ENODEV;
radio = kzalloc(sizeof(struct keene_device), GFP_KERNEL);
if (radio)
radio->buffer = kmalloc(BUFFER_LENGTH, GFP_KERNEL);
if (!radio || !radio->buffer) {
dev_err(&intf->dev, "kmalloc for keene_device failed\n");
kfree(radio);
retval = -ENOMEM;
goto err;
}
hdl = &radio->hdl;
v4l2_ctrl_handler_init(hdl, 4);
v4l2_ctrl_new_std(hdl, &keene_ctrl_ops, V4L2_CID_AUDIO_MUTE,
0, 1, 1, 0);
v4l2_ctrl_new_std_menu(hdl, &keene_ctrl_ops, V4L2_CID_TUNE_PREEMPHASIS,
V4L2_PREEMPHASIS_75_uS, 1, V4L2_PREEMPHASIS_50_uS);
v4l2_ctrl_new_std(hdl, &keene_ctrl_ops, V4L2_CID_TUNE_POWER_LEVEL,
84, 118, 1, 118);
v4l2_ctrl_new_std(hdl, &keene_ctrl_ops, V4L2_CID_AUDIO_COMPRESSION_GAIN,
-15, 18, 3, 0);
radio->pa = 118;
radio->tx = 0x32;
radio->stereo = true;
if (hdl->error) {
retval = hdl->error;
v4l2_ctrl_handler_free(hdl);
goto err_v4l2;
}
retval = v4l2_device_register(&intf->dev, &radio->v4l2_dev);
if (retval < 0) {
dev_err(&intf->dev, "couldn't register v4l2_device\n");
goto err_v4l2;
}
mutex_init(&radio->lock);
radio->v4l2_dev.ctrl_handler = hdl;
radio->v4l2_dev.release = usb_keene_video_device_release;
strlcpy(radio->vdev.name, radio->v4l2_dev.name,
sizeof(radio->vdev.name));
radio->vdev.v4l2_dev = &radio->v4l2_dev;
radio->vdev.fops = &usb_keene_fops;
radio->vdev.ioctl_ops = &usb_keene_ioctl_ops;
radio->vdev.lock = &radio->lock;
radio->vdev.release = video_device_release_empty;
radio->vdev.vfl_dir = VFL_DIR_TX;
radio->usbdev = interface_to_usbdev(intf);
radio->intf = intf;
usb_set_intfdata(intf, &radio->v4l2_dev);
video_set_drvdata(&radio->vdev, radio);
/* at least 11ms is needed in order to settle hardware */
msleep(20);
keene_cmd_main(radio, 95.16 * FREQ_MUL, false);
retval = video_register_device(&radio->vdev, VFL_TYPE_RADIO, -1);
if (retval < 0) {
dev_err(&intf->dev, "could not register video device\n");
goto err_vdev;
}
v4l2_ctrl_handler_setup(hdl);
dev_info(&intf->dev, "V4L2 device registered as %s\n",
video_device_node_name(&radio->vdev));
return 0;
err_vdev:
v4l2_device_unregister(&radio->v4l2_dev);
err_v4l2:
kfree(radio->buffer);
kfree(radio);
err:
return retval;
}
/* USB subsystem interface */
static struct usb_driver usb_keene_driver = {
.name = "radio-keene",
.probe = usb_keene_probe,
.disconnect = usb_keene_disconnect,
.id_table = usb_keene_device_table,
.suspend = usb_keene_suspend,
.resume = usb_keene_resume,
.reset_resume = usb_keene_resume,
};
module_usb_driver(usb_keene_driver);
