1/* 2 * vivid-radio-tx.c - radio transmitter support functions. 3 * 4 * Copyright 2014 Cisco Systems, Inc. and/or its affiliates. All rights reserved. 5 * 6 * This program is free software; you may redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; version 2 of the License. 9 * 10 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 11 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 12 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 13 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 14 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 15 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 16 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 17 * SOFTWARE. 18 */ 19 20#include <linux/errno.h> 21#include <linux/kernel.h> 22#include <linux/delay.h> 23#include <linux/videodev2.h> 24#include <linux/v4l2-dv-timings.h> 25#include <media/v4l2-common.h> 26#include <media/v4l2-event.h> 27#include <media/v4l2-dv-timings.h> 28 29#include "vivid-core.h" 30#include "vivid-ctrls.h" 31#include "vivid-radio-common.h" 32#include "vivid-radio-tx.h" 33 34ssize_t vivid_radio_tx_write(struct file *file, const char __user *buf, 35 size_t size, loff_t *offset) 36{ 37 struct vivid_dev *dev = video_drvdata(file); 38 struct v4l2_rds_data *data = dev->rds_gen.data; 39 struct timespec ts; 40 unsigned blk; 41 int i; 42 43 if (dev->radio_tx_rds_controls) 44 return -EINVAL; 45 46 if (size < sizeof(*data)) 47 return -EINVAL; 48 size = sizeof(*data) * (size / sizeof(*data)); 49 50 if (mutex_lock_interruptible(&dev->mutex)) 51 return -ERESTARTSYS; 52 if (dev->radio_tx_rds_owner && 53 file->private_data != dev->radio_tx_rds_owner) { 54 mutex_unlock(&dev->mutex); 55 return -EBUSY; 56 } 57 dev->radio_tx_rds_owner = file->private_data; 58 59retry: 60 ktime_get_ts(&ts); 61 ts = timespec_sub(ts, dev->radio_rds_init_ts); 62 blk = ts.tv_sec * 100 + ts.tv_nsec / 10000000; 63 blk = (blk * VIVID_RDS_GEN_BLOCKS) / 500; 64 if (blk - VIVID_RDS_GEN_BLOCKS >= dev->radio_tx_rds_last_block) 65 dev->radio_tx_rds_last_block = blk - VIVID_RDS_GEN_BLOCKS + 1; 66 67 /* 68 * No data is available if there hasn't been time to get new data, 69 * or if the RDS receiver has been disabled, or if we use the data 70 * from the RDS transmitter and that RDS transmitter has been disabled, 71 * or if the signal quality is too weak. 72 */ 73 if (blk == dev->radio_tx_rds_last_block || 74 !(dev->radio_tx_subchans & V4L2_TUNER_SUB_RDS)) { 75 mutex_unlock(&dev->mutex); 76 if (file->f_flags & O_NONBLOCK) 77 return -EWOULDBLOCK; 78 if (msleep_interruptible(20) && signal_pending(current)) 79 return -EINTR; 80 if (mutex_lock_interruptible(&dev->mutex)) 81 return -ERESTARTSYS; 82 goto retry; 83 } 84 85 for (i = 0; i < size && blk > dev->radio_tx_rds_last_block; 86 dev->radio_tx_rds_last_block++) { 87 unsigned data_blk = dev->radio_tx_rds_last_block % VIVID_RDS_GEN_BLOCKS; 88 struct v4l2_rds_data rds; 89 90 if (copy_from_user(&rds, buf + i, sizeof(rds))) { 91 i = -EFAULT; 92 break; 93 } 94 i += sizeof(rds); 95 if (!dev->radio_rds_loop) 96 continue; 97 if ((rds.block & V4L2_RDS_BLOCK_MSK) == V4L2_RDS_BLOCK_INVALID || 98 (rds.block & V4L2_RDS_BLOCK_ERROR)) 99 continue; 100 rds.block &= V4L2_RDS_BLOCK_MSK; 101 data[data_blk] = rds; 102 } 103 mutex_unlock(&dev->mutex); 104 return i; 105} 106 107unsigned int vivid_radio_tx_poll(struct file *file, struct poll_table_struct *wait) 108{ 109 return POLLOUT | POLLWRNORM | v4l2_ctrl_poll(file, wait); 110} 111 112int vidioc_g_modulator(struct file *file, void *fh, struct v4l2_modulator *a) 113{ 114 struct vivid_dev *dev = video_drvdata(file); 115 116 if (a->index > 0) 117 return -EINVAL; 118 119 strlcpy(a->name, "AM/FM/SW Transmitter", sizeof(a->name)); 120 a->capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_STEREO | 121 V4L2_TUNER_CAP_FREQ_BANDS | V4L2_TUNER_CAP_RDS | 122 (dev->radio_tx_rds_controls ? 123 V4L2_TUNER_CAP_RDS_CONTROLS : 124 V4L2_TUNER_CAP_RDS_BLOCK_IO); 125 a->rangelow = AM_FREQ_RANGE_LOW; 126 a->rangehigh = FM_FREQ_RANGE_HIGH; 127 a->txsubchans = dev->radio_tx_subchans; 128 return 0; 129} 130 131int vidioc_s_modulator(struct file *file, void *fh, const struct v4l2_modulator *a) 132{ 133 struct vivid_dev *dev = video_drvdata(file); 134 135 if (a->index) 136 return -EINVAL; 137 if (a->txsubchans & ~0x13) 138 return -EINVAL; 139 dev->radio_tx_subchans = a->txsubchans; 140 return 0; 141} 142