/* * 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. */ /* 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 const 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); strscpy(v->driver, "radio-keene", sizeof(v->driver)); strscpy(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; strscpy(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; strscpy(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);