diff options
Diffstat (limited to 'drivers/media/platform/vivid/vivid-radio-tx.c')
-rw-r--r-- | drivers/media/platform/vivid/vivid-radio-tx.c | 128 |
1 files changed, 128 insertions, 0 deletions
diff --git a/drivers/media/platform/vivid/vivid-radio-tx.c b/drivers/media/platform/vivid/vivid-radio-tx.c new file mode 100644 index 000000000..1a3749ba5 --- /dev/null +++ b/drivers/media/platform/vivid/vivid-radio-tx.c @@ -0,0 +1,128 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * vivid-radio-tx.c - radio transmitter support functions. + * + * Copyright 2014 Cisco Systems, Inc. and/or its affiliates. All rights reserved. + */ + +#include <linux/errno.h> +#include <linux/kernel.h> +#include <linux/sched/signal.h> +#include <linux/delay.h> +#include <linux/videodev2.h> +#include <linux/v4l2-dv-timings.h> +#include <media/v4l2-common.h> +#include <media/v4l2-event.h> +#include <media/v4l2-dv-timings.h> + +#include "vivid-core.h" +#include "vivid-ctrls.h" +#include "vivid-radio-common.h" +#include "vivid-radio-tx.h" + +ssize_t vivid_radio_tx_write(struct file *file, const char __user *buf, + size_t size, loff_t *offset) +{ + struct vivid_dev *dev = video_drvdata(file); + struct v4l2_rds_data *data = dev->rds_gen.data; + ktime_t timestamp; + unsigned blk; + int i; + + if (dev->radio_tx_rds_controls) + return -EINVAL; + + if (size < sizeof(*data)) + return -EINVAL; + size = sizeof(*data) * (size / sizeof(*data)); + + if (mutex_lock_interruptible(&dev->mutex)) + return -ERESTARTSYS; + if (dev->radio_tx_rds_owner && + file->private_data != dev->radio_tx_rds_owner) { + mutex_unlock(&dev->mutex); + return -EBUSY; + } + dev->radio_tx_rds_owner = file->private_data; + +retry: + timestamp = ktime_sub(ktime_get(), dev->radio_rds_init_time); + blk = ktime_divns(timestamp, VIVID_RDS_NSEC_PER_BLK); + if (blk - VIVID_RDS_GEN_BLOCKS >= dev->radio_tx_rds_last_block) + dev->radio_tx_rds_last_block = blk - VIVID_RDS_GEN_BLOCKS + 1; + + /* + * No data is available if there hasn't been time to get new data, + * or if the RDS receiver has been disabled, or if we use the data + * from the RDS transmitter and that RDS transmitter has been disabled, + * or if the signal quality is too weak. + */ + if (blk == dev->radio_tx_rds_last_block || + !(dev->radio_tx_subchans & V4L2_TUNER_SUB_RDS)) { + mutex_unlock(&dev->mutex); + if (file->f_flags & O_NONBLOCK) + return -EWOULDBLOCK; + if (msleep_interruptible(20) && signal_pending(current)) + return -EINTR; + if (mutex_lock_interruptible(&dev->mutex)) + return -ERESTARTSYS; + goto retry; + } + + for (i = 0; i < size && blk > dev->radio_tx_rds_last_block; + dev->radio_tx_rds_last_block++) { + unsigned data_blk = dev->radio_tx_rds_last_block % VIVID_RDS_GEN_BLOCKS; + struct v4l2_rds_data rds; + + if (copy_from_user(&rds, buf + i, sizeof(rds))) { + i = -EFAULT; + break; + } + i += sizeof(rds); + if (!dev->radio_rds_loop) + continue; + if ((rds.block & V4L2_RDS_BLOCK_MSK) == V4L2_RDS_BLOCK_INVALID || + (rds.block & V4L2_RDS_BLOCK_ERROR)) + continue; + rds.block &= V4L2_RDS_BLOCK_MSK; + data[data_blk] = rds; + } + mutex_unlock(&dev->mutex); + return i; +} + +__poll_t vivid_radio_tx_poll(struct file *file, struct poll_table_struct *wait) +{ + return EPOLLOUT | EPOLLWRNORM | v4l2_ctrl_poll(file, wait); +} + +int vidioc_g_modulator(struct file *file, void *fh, struct v4l2_modulator *a) +{ + struct vivid_dev *dev = video_drvdata(file); + + if (a->index > 0) + return -EINVAL; + + strlcpy(a->name, "AM/FM/SW Transmitter", sizeof(a->name)); + a->capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_STEREO | + V4L2_TUNER_CAP_FREQ_BANDS | V4L2_TUNER_CAP_RDS | + (dev->radio_tx_rds_controls ? + V4L2_TUNER_CAP_RDS_CONTROLS : + V4L2_TUNER_CAP_RDS_BLOCK_IO); + a->rangelow = AM_FREQ_RANGE_LOW; + a->rangehigh = FM_FREQ_RANGE_HIGH; + a->txsubchans = dev->radio_tx_subchans; + return 0; +} + +int vidioc_s_modulator(struct file *file, void *fh, const struct v4l2_modulator *a) +{ + struct vivid_dev *dev = video_drvdata(file); + + if (a->index) + return -EINVAL; + if (a->txsubchans & ~0x13) + return -EINVAL; + dev->radio_tx_subchans = a->txsubchans; + return 0; +} |