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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Copyright (c) 2012 Hans Verkuil <hverkuil@xs4all.nl>4 */5 6/* kernel includes */7#include <linux/kernel.h>8#include <linux/module.h>9#include <linux/init.h>10#include <linux/slab.h>11#include <linux/input.h>12#include <linux/videodev2.h>13#include <media/v4l2-device.h>14#include <media/v4l2-ioctl.h>15#include <media/v4l2-ctrls.h>16#include <media/v4l2-event.h>17#include <linux/usb.h>18#include <linux/mutex.h>19 20/* driver and module definitions */21MODULE_AUTHOR("Hans Verkuil <hverkuil@xs4all.nl>");22MODULE_DESCRIPTION("Keene FM Transmitter driver");23MODULE_LICENSE("GPL");24 25/* Actually, it advertises itself as a Logitech */26#define USB_KEENE_VENDOR 0x046d27#define USB_KEENE_PRODUCT 0x0a0e28 29/* Probably USB_TIMEOUT should be modified in module parameter */30#define BUFFER_LENGTH 831#define USB_TIMEOUT 50032 33/* Frequency limits in MHz */34#define FREQ_MIN 76U35#define FREQ_MAX 108U36#define FREQ_MUL 16000U37 38/* USB Device ID List */39static const struct usb_device_id usb_keene_device_table[] = {40 {USB_DEVICE_AND_INTERFACE_INFO(USB_KEENE_VENDOR, USB_KEENE_PRODUCT,41 USB_CLASS_HID, 0, 0) },42 { } /* Terminating entry */43};44 45MODULE_DEVICE_TABLE(usb, usb_keene_device_table);46 47struct keene_device {48 struct usb_device *usbdev;49 struct usb_interface *intf;50 struct video_device vdev;51 struct v4l2_device v4l2_dev;52 struct v4l2_ctrl_handler hdl;53 struct mutex lock;54 55 u8 *buffer;56 unsigned curfreq;57 u8 tx;58 u8 pa;59 bool stereo;60 bool muted;61 bool preemph_75_us;62};63 64static inline struct keene_device *to_keene_dev(struct v4l2_device *v4l2_dev)65{66 return container_of(v4l2_dev, struct keene_device, v4l2_dev);67}68 69/* Set frequency (if non-0), PA, mute and turn on/off the FM transmitter. */70static int keene_cmd_main(struct keene_device *radio, unsigned freq, bool play)71{72 unsigned short freq_send = freq ? (freq - 76 * 16000) / 800 : 0;73 int ret;74 75 radio->buffer[0] = 0x00;76 radio->buffer[1] = 0x50;77 radio->buffer[2] = (freq_send >> 8) & 0xff;78 radio->buffer[3] = freq_send & 0xff;79 radio->buffer[4] = radio->pa;80 /* If bit 4 is set, then tune to the frequency.81 If bit 3 is set, then unmute; if bit 2 is set, then mute.82 If bit 1 is set, then enter idle mode; if bit 0 is set,83 then enter transmit mode.84 */85 radio->buffer[5] = (radio->muted ? 4 : 8) | (play ? 1 : 2) |86 (freq ? 0x10 : 0);87 radio->buffer[6] = 0x00;88 radio->buffer[7] = 0x00;89 90 ret = usb_control_msg(radio->usbdev, usb_sndctrlpipe(radio->usbdev, 0),91 9, 0x21, 0x200, 2, radio->buffer, BUFFER_LENGTH, USB_TIMEOUT);92 93 if (ret < 0) {94 dev_warn(&radio->vdev.dev, "%s failed (%d)\n", __func__, ret);95 return ret;96 }97 if (freq)98 radio->curfreq = freq;99 return 0;100}101 102/* Set TX, stereo and preemphasis mode (50 us vs 75 us). */103static int keene_cmd_set(struct keene_device *radio)104{105 int ret;106 107 radio->buffer[0] = 0x00;108 radio->buffer[1] = 0x51;109 radio->buffer[2] = radio->tx;110 /* If bit 0 is set, then transmit mono, otherwise stereo.111 If bit 2 is set, then enable 75 us preemphasis, otherwise112 it is 50 us. */113 radio->buffer[3] = (radio->stereo ? 0 : 1) | (radio->preemph_75_us ? 4 : 0);114 radio->buffer[4] = 0x00;115 radio->buffer[5] = 0x00;116 radio->buffer[6] = 0x00;117 radio->buffer[7] = 0x00;118 119 ret = usb_control_msg(radio->usbdev, usb_sndctrlpipe(radio->usbdev, 0),120 9, 0x21, 0x200, 2, radio->buffer, BUFFER_LENGTH, USB_TIMEOUT);121 122 if (ret < 0) {123 dev_warn(&radio->vdev.dev, "%s failed (%d)\n", __func__, ret);124 return ret;125 }126 return 0;127}128 129/* Handle unplugging the device.130 * We call video_unregister_device in any case.131 * The last function called in this procedure is132 * usb_keene_device_release.133 */134static void usb_keene_disconnect(struct usb_interface *intf)135{136 struct keene_device *radio = to_keene_dev(usb_get_intfdata(intf));137 138 mutex_lock(&radio->lock);139 usb_set_intfdata(intf, NULL);140 video_unregister_device(&radio->vdev);141 v4l2_device_disconnect(&radio->v4l2_dev);142 mutex_unlock(&radio->lock);143 v4l2_device_put(&radio->v4l2_dev);144}145 146static int usb_keene_suspend(struct usb_interface *intf, pm_message_t message)147{148 struct keene_device *radio = to_keene_dev(usb_get_intfdata(intf));149 150 return keene_cmd_main(radio, 0, false);151}152 153static int usb_keene_resume(struct usb_interface *intf)154{155 struct keene_device *radio = to_keene_dev(usb_get_intfdata(intf));156 157 mdelay(50);158 keene_cmd_set(radio);159 keene_cmd_main(radio, radio->curfreq, true);160 return 0;161}162 163static int vidioc_querycap(struct file *file, void *priv,164 struct v4l2_capability *v)165{166 struct keene_device *radio = video_drvdata(file);167 168 strscpy(v->driver, "radio-keene", sizeof(v->driver));169 strscpy(v->card, "Keene FM Transmitter", sizeof(v->card));170 usb_make_path(radio->usbdev, v->bus_info, sizeof(v->bus_info));171 return 0;172}173 174static int vidioc_g_modulator(struct file *file, void *priv,175 struct v4l2_modulator *v)176{177 struct keene_device *radio = video_drvdata(file);178 179 if (v->index > 0)180 return -EINVAL;181 182 strscpy(v->name, "FM", sizeof(v->name));183 v->rangelow = FREQ_MIN * FREQ_MUL;184 v->rangehigh = FREQ_MAX * FREQ_MUL;185 v->txsubchans = radio->stereo ? V4L2_TUNER_SUB_STEREO : V4L2_TUNER_SUB_MONO;186 v->capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_STEREO;187 return 0;188}189 190static int vidioc_s_modulator(struct file *file, void *priv,191 const struct v4l2_modulator *v)192{193 struct keene_device *radio = video_drvdata(file);194 195 if (v->index > 0)196 return -EINVAL;197 198 radio->stereo = (v->txsubchans == V4L2_TUNER_SUB_STEREO);199 return keene_cmd_set(radio);200}201 202static int vidioc_s_frequency(struct file *file, void *priv,203 const struct v4l2_frequency *f)204{205 struct keene_device *radio = video_drvdata(file);206 unsigned freq = f->frequency;207 208 if (f->tuner != 0 || f->type != V4L2_TUNER_RADIO)209 return -EINVAL;210 freq = clamp(freq, FREQ_MIN * FREQ_MUL, FREQ_MAX * FREQ_MUL);211 return keene_cmd_main(radio, freq, true);212}213 214static int vidioc_g_frequency(struct file *file, void *priv,215 struct v4l2_frequency *f)216{217 struct keene_device *radio = video_drvdata(file);218 219 if (f->tuner != 0)220 return -EINVAL;221 f->type = V4L2_TUNER_RADIO;222 f->frequency = radio->curfreq;223 return 0;224}225 226static int keene_s_ctrl(struct v4l2_ctrl *ctrl)227{228 static const u8 db2tx[] = {229 /* -15, -12, -9, -6, -3, 0 dB */230 0x03, 0x13, 0x02, 0x12, 0x22, 0x32,231 /* 3, 6, 9, 12, 15, 18 dB */232 0x21, 0x31, 0x20, 0x30, 0x40, 0x50233 };234 struct keene_device *radio =235 container_of(ctrl->handler, struct keene_device, hdl);236 237 switch (ctrl->id) {238 case V4L2_CID_AUDIO_MUTE:239 radio->muted = ctrl->val;240 return keene_cmd_main(radio, 0, true);241 242 case V4L2_CID_TUNE_POWER_LEVEL:243 /* To go from dBuV to the register value we apply the244 following formula: */245 radio->pa = (ctrl->val - 71) * 100 / 62;246 return keene_cmd_main(radio, 0, true);247 248 case V4L2_CID_TUNE_PREEMPHASIS:249 radio->preemph_75_us = ctrl->val == V4L2_PREEMPHASIS_75_uS;250 return keene_cmd_set(radio);251 252 case V4L2_CID_AUDIO_COMPRESSION_GAIN:253 radio->tx = db2tx[(ctrl->val - (s32)ctrl->minimum) / (s32)ctrl->step];254 return keene_cmd_set(radio);255 }256 return -EINVAL;257}258 259/* File system interface */260static const struct v4l2_file_operations usb_keene_fops = {261 .owner = THIS_MODULE,262 .open = v4l2_fh_open,263 .release = v4l2_fh_release,264 .poll = v4l2_ctrl_poll,265 .unlocked_ioctl = video_ioctl2,266};267 268static const struct v4l2_ctrl_ops keene_ctrl_ops = {269 .s_ctrl = keene_s_ctrl,270};271 272static const struct v4l2_ioctl_ops usb_keene_ioctl_ops = {273 .vidioc_querycap = vidioc_querycap,274 .vidioc_g_modulator = vidioc_g_modulator,275 .vidioc_s_modulator = vidioc_s_modulator,276 .vidioc_g_frequency = vidioc_g_frequency,277 .vidioc_s_frequency = vidioc_s_frequency,278 .vidioc_log_status = v4l2_ctrl_log_status,279 .vidioc_subscribe_event = v4l2_ctrl_subscribe_event,280 .vidioc_unsubscribe_event = v4l2_event_unsubscribe,281};282 283static void usb_keene_video_device_release(struct v4l2_device *v4l2_dev)284{285 struct keene_device *radio = to_keene_dev(v4l2_dev);286 287 /* free rest memory */288 v4l2_ctrl_handler_free(&radio->hdl);289 kfree(radio->buffer);290 kfree(radio);291}292 293/* check if the device is present and register with v4l and usb if it is */294static int usb_keene_probe(struct usb_interface *intf,295 const struct usb_device_id *id)296{297 struct usb_device *dev = interface_to_usbdev(intf);298 struct keene_device *radio;299 struct v4l2_ctrl_handler *hdl;300 int retval = 0;301 302 /*303 * The Keene FM transmitter USB device has the same USB ID as304 * the Logitech AudioHub Speaker, but it should ignore the hid.305 * Check if the name is that of the Keene device.306 * If not, then someone connected the AudioHub and we shouldn't307 * attempt to handle this driver.308 * For reference: the product name of the AudioHub is309 * "AudioHub Speaker".310 */311 if (dev->product && strcmp(dev->product, "B-LINK USB Audio "))312 return -ENODEV;313 314 radio = kzalloc(sizeof(struct keene_device), GFP_KERNEL);315 if (radio)316 radio->buffer = kmalloc(BUFFER_LENGTH, GFP_KERNEL);317 318 if (!radio || !radio->buffer) {319 dev_err(&intf->dev, "kmalloc for keene_device failed\n");320 kfree(radio);321 retval = -ENOMEM;322 goto err;323 }324 325 hdl = &radio->hdl;326 v4l2_ctrl_handler_init(hdl, 4);327 v4l2_ctrl_new_std(hdl, &keene_ctrl_ops, V4L2_CID_AUDIO_MUTE,328 0, 1, 1, 0);329 v4l2_ctrl_new_std_menu(hdl, &keene_ctrl_ops, V4L2_CID_TUNE_PREEMPHASIS,330 V4L2_PREEMPHASIS_75_uS, 1, V4L2_PREEMPHASIS_50_uS);331 v4l2_ctrl_new_std(hdl, &keene_ctrl_ops, V4L2_CID_TUNE_POWER_LEVEL,332 84, 118, 1, 118);333 v4l2_ctrl_new_std(hdl, &keene_ctrl_ops, V4L2_CID_AUDIO_COMPRESSION_GAIN,334 -15, 18, 3, 0);335 radio->pa = 118;336 radio->tx = 0x32;337 radio->stereo = true;338 if (hdl->error) {339 retval = hdl->error;340 341 v4l2_ctrl_handler_free(hdl);342 goto err_v4l2;343 }344 retval = v4l2_device_register(&intf->dev, &radio->v4l2_dev);345 if (retval < 0) {346 dev_err(&intf->dev, "couldn't register v4l2_device\n");347 goto err_v4l2;348 }349 350 mutex_init(&radio->lock);351 352 radio->v4l2_dev.ctrl_handler = hdl;353 radio->v4l2_dev.release = usb_keene_video_device_release;354 strscpy(radio->vdev.name, radio->v4l2_dev.name,355 sizeof(radio->vdev.name));356 radio->vdev.v4l2_dev = &radio->v4l2_dev;357 radio->vdev.fops = &usb_keene_fops;358 radio->vdev.ioctl_ops = &usb_keene_ioctl_ops;359 radio->vdev.lock = &radio->lock;360 radio->vdev.release = video_device_release_empty;361 radio->vdev.vfl_dir = VFL_DIR_TX;362 radio->vdev.device_caps = V4L2_CAP_RADIO | V4L2_CAP_MODULATOR;363 364 radio->usbdev = interface_to_usbdev(intf);365 radio->intf = intf;366 usb_set_intfdata(intf, &radio->v4l2_dev);367 368 video_set_drvdata(&radio->vdev, radio);369 370 /* at least 11ms is needed in order to settle hardware */371 msleep(20);372 keene_cmd_main(radio, 95.16 * FREQ_MUL, false);373 374 retval = video_register_device(&radio->vdev, VFL_TYPE_RADIO, -1);375 if (retval < 0) {376 dev_err(&intf->dev, "could not register video device\n");377 goto err_vdev;378 }379 v4l2_ctrl_handler_setup(hdl);380 dev_info(&intf->dev, "V4L2 device registered as %s\n",381 video_device_node_name(&radio->vdev));382 return 0;383 384err_vdev:385 v4l2_device_unregister(&radio->v4l2_dev);386err_v4l2:387 kfree(radio->buffer);388 kfree(radio);389err:390 return retval;391}392 393/* USB subsystem interface */394static struct usb_driver usb_keene_driver = {395 .name = "radio-keene",396 .probe = usb_keene_probe,397 .disconnect = usb_keene_disconnect,398 .id_table = usb_keene_device_table,399 .suspend = usb_keene_suspend,400 .resume = usb_keene_resume,401 .reset_resume = usb_keene_resume,402};403 404module_usb_driver(usb_keene_driver);405 406