diff options
Diffstat (limited to 'drivers/media/platform/vivid/vivid-radio-common.c')
| -rw-r--r-- | drivers/media/platform/vivid/vivid-radio-common.c | 177 |
1 files changed, 177 insertions, 0 deletions
diff --git a/drivers/media/platform/vivid/vivid-radio-common.c b/drivers/media/platform/vivid/vivid-radio-common.c new file mode 100644 index 000000000..7c8efe38f --- /dev/null +++ b/drivers/media/platform/vivid/vivid-radio-common.c @@ -0,0 +1,177 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * vivid-radio-common.c - common radio rx/tx support functions. + * + * Copyright 2014 Cisco Systems, Inc. and/or its affiliates. All rights reserved. + */ + +#include <linux/errno.h> +#include <linux/kernel.h> +#include <linux/delay.h> +#include <linux/videodev2.h> + +#include "vivid-core.h" +#include "vivid-ctrls.h" +#include "vivid-radio-common.h" +#include "vivid-rds-gen.h" + +/* + * These functions are shared between the vivid receiver and transmitter + * since both use the same frequency bands. + */ + +const struct v4l2_frequency_band vivid_radio_bands[TOT_BANDS] = { + /* Band FM */ + { + .type = V4L2_TUNER_RADIO, + .index = 0, + .capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_STEREO | + V4L2_TUNER_CAP_FREQ_BANDS, + .rangelow = FM_FREQ_RANGE_LOW, + .rangehigh = FM_FREQ_RANGE_HIGH, + .modulation = V4L2_BAND_MODULATION_FM, + }, + /* Band AM */ + { + .type = V4L2_TUNER_RADIO, + .index = 1, + .capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_FREQ_BANDS, + .rangelow = AM_FREQ_RANGE_LOW, + .rangehigh = AM_FREQ_RANGE_HIGH, + .modulation = V4L2_BAND_MODULATION_AM, + }, + /* Band SW */ + { + .type = V4L2_TUNER_RADIO, + .index = 2, + .capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_FREQ_BANDS, + .rangelow = SW_FREQ_RANGE_LOW, + .rangehigh = SW_FREQ_RANGE_HIGH, + .modulation = V4L2_BAND_MODULATION_AM, + }, +}; + +/* + * Initialize the RDS generator. If we can loop, then the RDS generator + * is set up with the values from the RDS TX controls, otherwise it + * will fill in standard values using one of two alternates. + */ +void vivid_radio_rds_init(struct vivid_dev *dev) +{ + struct vivid_rds_gen *rds = &dev->rds_gen; + bool alt = dev->radio_rx_rds_use_alternates; + + /* Do nothing, blocks will be filled by the transmitter */ + if (dev->radio_rds_loop && !dev->radio_tx_rds_controls) + return; + + if (dev->radio_rds_loop) { + v4l2_ctrl_lock(dev->radio_tx_rds_pi); + rds->picode = dev->radio_tx_rds_pi->cur.val; + rds->pty = dev->radio_tx_rds_pty->cur.val; + rds->mono_stereo = dev->radio_tx_rds_mono_stereo->cur.val; + rds->art_head = dev->radio_tx_rds_art_head->cur.val; + rds->compressed = dev->radio_tx_rds_compressed->cur.val; + rds->dyn_pty = dev->radio_tx_rds_dyn_pty->cur.val; + rds->ta = dev->radio_tx_rds_ta->cur.val; + rds->tp = dev->radio_tx_rds_tp->cur.val; + rds->ms = dev->radio_tx_rds_ms->cur.val; + strlcpy(rds->psname, + dev->radio_tx_rds_psname->p_cur.p_char, + sizeof(rds->psname)); + strlcpy(rds->radiotext, + dev->radio_tx_rds_radiotext->p_cur.p_char + alt * 64, + sizeof(rds->radiotext)); + v4l2_ctrl_unlock(dev->radio_tx_rds_pi); + } else { + vivid_rds_gen_fill(rds, dev->radio_rx_freq, alt); + } + if (dev->radio_rx_rds_controls) { + v4l2_ctrl_s_ctrl(dev->radio_rx_rds_pty, rds->pty); + v4l2_ctrl_s_ctrl(dev->radio_rx_rds_ta, rds->ta); + v4l2_ctrl_s_ctrl(dev->radio_rx_rds_tp, rds->tp); + v4l2_ctrl_s_ctrl(dev->radio_rx_rds_ms, rds->ms); + v4l2_ctrl_s_ctrl_string(dev->radio_rx_rds_psname, rds->psname); + v4l2_ctrl_s_ctrl_string(dev->radio_rx_rds_radiotext, rds->radiotext); + if (!dev->radio_rds_loop) + dev->radio_rx_rds_use_alternates = !dev->radio_rx_rds_use_alternates; + } + vivid_rds_generate(rds); +} + +/* + * Calculate the emulated signal quality taking into account the frequency + * the transmitter is using. + */ +static void vivid_radio_calc_sig_qual(struct vivid_dev *dev) +{ + int mod = 16000; + int delta = 800; + int sig_qual, sig_qual_tx = mod; + + /* + * For SW and FM there is a channel every 1000 kHz, for AM there is one + * every 100 kHz. + */ + if (dev->radio_rx_freq <= AM_FREQ_RANGE_HIGH) { + mod /= 10; + delta /= 10; + } + sig_qual = (dev->radio_rx_freq + delta) % mod - delta; + if (dev->has_radio_tx) + sig_qual_tx = dev->radio_rx_freq - dev->radio_tx_freq; + if (abs(sig_qual_tx) <= abs(sig_qual)) { + sig_qual = sig_qual_tx; + /* + * Zero the internal rds buffer if we are going to loop + * rds blocks. + */ + if (!dev->radio_rds_loop && !dev->radio_tx_rds_controls) + memset(dev->rds_gen.data, 0, + sizeof(dev->rds_gen.data)); + dev->radio_rds_loop = dev->radio_rx_freq >= FM_FREQ_RANGE_LOW; + } else { + dev->radio_rds_loop = false; + } + if (dev->radio_rx_freq <= AM_FREQ_RANGE_HIGH) + sig_qual *= 10; + dev->radio_rx_sig_qual = sig_qual; +} + +int vivid_radio_g_frequency(struct file *file, const unsigned *pfreq, struct v4l2_frequency *vf) +{ + if (vf->tuner != 0) + return -EINVAL; + vf->frequency = *pfreq; + return 0; +} + +int vivid_radio_s_frequency(struct file *file, unsigned *pfreq, const struct v4l2_frequency *vf) +{ + struct vivid_dev *dev = video_drvdata(file); + unsigned freq; + unsigned band; + + if (vf->tuner != 0) + return -EINVAL; + + if (vf->frequency >= (FM_FREQ_RANGE_LOW + SW_FREQ_RANGE_HIGH) / 2) + band = BAND_FM; + else if (vf->frequency <= (AM_FREQ_RANGE_HIGH + SW_FREQ_RANGE_LOW) / 2) + band = BAND_AM; + else + band = BAND_SW; + + freq = clamp_t(u32, vf->frequency, vivid_radio_bands[band].rangelow, + vivid_radio_bands[band].rangehigh); + *pfreq = freq; + + /* + * For both receiver and transmitter recalculate the signal quality + * (since that depends on both frequencies) and re-init the rds + * generator. + */ + vivid_radio_calc_sig_qual(dev); + vivid_radio_rds_init(dev); + return 0; +} |