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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * vivid-radio-common.c - common radio rx/tx support functions.4 *5 * Copyright 2014 Cisco Systems, Inc. and/or its affiliates. All rights reserved.6 */7 8#include <linux/errno.h>9#include <linux/kernel.h>10#include <linux/delay.h>11#include <linux/videodev2.h>12 13#include "vivid-core.h"14#include "vivid-ctrls.h"15#include "vivid-radio-common.h"16#include "vivid-rds-gen.h"17 18/*19 * These functions are shared between the vivid receiver and transmitter20 * since both use the same frequency bands.21 */22 23const struct v4l2_frequency_band vivid_radio_bands[TOT_BANDS] = {24 /* Band FM */25 {26 .type = V4L2_TUNER_RADIO,27 .index = 0,28 .capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_STEREO |29 V4L2_TUNER_CAP_FREQ_BANDS,30 .rangelow = FM_FREQ_RANGE_LOW,31 .rangehigh = FM_FREQ_RANGE_HIGH,32 .modulation = V4L2_BAND_MODULATION_FM,33 },34 /* Band AM */35 {36 .type = V4L2_TUNER_RADIO,37 .index = 1,38 .capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_FREQ_BANDS,39 .rangelow = AM_FREQ_RANGE_LOW,40 .rangehigh = AM_FREQ_RANGE_HIGH,41 .modulation = V4L2_BAND_MODULATION_AM,42 },43 /* Band SW */44 {45 .type = V4L2_TUNER_RADIO,46 .index = 2,47 .capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_FREQ_BANDS,48 .rangelow = SW_FREQ_RANGE_LOW,49 .rangehigh = SW_FREQ_RANGE_HIGH,50 .modulation = V4L2_BAND_MODULATION_AM,51 },52};53 54/*55 * Initialize the RDS generator. If we can loop, then the RDS generator56 * is set up with the values from the RDS TX controls, otherwise it57 * will fill in standard values using one of two alternates.58 */59void vivid_radio_rds_init(struct vivid_dev *dev)60{61 struct vivid_rds_gen *rds = &dev->rds_gen;62 bool alt = dev->radio_rx_rds_use_alternates;63 64 /* Do nothing, blocks will be filled by the transmitter */65 if (dev->radio_rds_loop && !dev->radio_tx_rds_controls)66 return;67 68 if (dev->radio_rds_loop) {69 v4l2_ctrl_lock(dev->radio_tx_rds_pi);70 rds->picode = dev->radio_tx_rds_pi->cur.val;71 rds->pty = dev->radio_tx_rds_pty->cur.val;72 rds->mono_stereo = dev->radio_tx_rds_mono_stereo->cur.val;73 rds->art_head = dev->radio_tx_rds_art_head->cur.val;74 rds->compressed = dev->radio_tx_rds_compressed->cur.val;75 rds->dyn_pty = dev->radio_tx_rds_dyn_pty->cur.val;76 rds->ta = dev->radio_tx_rds_ta->cur.val;77 rds->tp = dev->radio_tx_rds_tp->cur.val;78 rds->ms = dev->radio_tx_rds_ms->cur.val;79 strscpy(rds->psname,80 dev->radio_tx_rds_psname->p_cur.p_char,81 sizeof(rds->psname));82 strscpy(rds->radiotext,83 dev->radio_tx_rds_radiotext->p_cur.p_char + alt * 64,84 sizeof(rds->radiotext));85 v4l2_ctrl_unlock(dev->radio_tx_rds_pi);86 } else {87 vivid_rds_gen_fill(rds, dev->radio_rx_freq, alt);88 }89 if (dev->radio_rx_rds_controls) {90 v4l2_ctrl_s_ctrl(dev->radio_rx_rds_pty, rds->pty);91 v4l2_ctrl_s_ctrl(dev->radio_rx_rds_ta, rds->ta);92 v4l2_ctrl_s_ctrl(dev->radio_rx_rds_tp, rds->tp);93 v4l2_ctrl_s_ctrl(dev->radio_rx_rds_ms, rds->ms);94 v4l2_ctrl_s_ctrl_string(dev->radio_rx_rds_psname, rds->psname);95 v4l2_ctrl_s_ctrl_string(dev->radio_rx_rds_radiotext, rds->radiotext);96 if (!dev->radio_rds_loop)97 dev->radio_rx_rds_use_alternates = !dev->radio_rx_rds_use_alternates;98 }99 vivid_rds_generate(rds);100}101 102/*103 * Calculate the emulated signal quality taking into account the frequency104 * the transmitter is using.105 */106static void vivid_radio_calc_sig_qual(struct vivid_dev *dev)107{108 int mod = 16000;109 int delta = 800;110 int sig_qual, sig_qual_tx = mod;111 112 /*113 * For SW and FM there is a channel every 1000 kHz, for AM there is one114 * every 100 kHz.115 */116 if (dev->radio_rx_freq <= AM_FREQ_RANGE_HIGH) {117 mod /= 10;118 delta /= 10;119 }120 sig_qual = (dev->radio_rx_freq + delta) % mod - delta;121 if (dev->has_radio_tx)122 sig_qual_tx = dev->radio_rx_freq - dev->radio_tx_freq;123 if (abs(sig_qual_tx) <= abs(sig_qual)) {124 sig_qual = sig_qual_tx;125 /*126 * Zero the internal rds buffer if we are going to loop127 * rds blocks.128 */129 if (!dev->radio_rds_loop && !dev->radio_tx_rds_controls)130 memset(dev->rds_gen.data, 0,131 sizeof(dev->rds_gen.data));132 dev->radio_rds_loop = dev->radio_rx_freq >= FM_FREQ_RANGE_LOW;133 } else {134 dev->radio_rds_loop = false;135 }136 if (dev->radio_rx_freq <= AM_FREQ_RANGE_HIGH)137 sig_qual *= 10;138 dev->radio_rx_sig_qual = sig_qual;139}140 141int vivid_radio_g_frequency(struct file *file, const unsigned *pfreq, struct v4l2_frequency *vf)142{143 if (vf->tuner != 0)144 return -EINVAL;145 vf->frequency = *pfreq;146 return 0;147}148 149int vivid_radio_s_frequency(struct file *file, unsigned *pfreq, const struct v4l2_frequency *vf)150{151 struct vivid_dev *dev = video_drvdata(file);152 unsigned freq;153 unsigned band;154 155 if (vf->tuner != 0)156 return -EINVAL;157 158 if (vf->frequency >= (FM_FREQ_RANGE_LOW + SW_FREQ_RANGE_HIGH) / 2)159 band = BAND_FM;160 else if (vf->frequency <= (AM_FREQ_RANGE_HIGH + SW_FREQ_RANGE_LOW) / 2)161 band = BAND_AM;162 else163 band = BAND_SW;164 165 freq = clamp_t(u32, vf->frequency, vivid_radio_bands[band].rangelow,166 vivid_radio_bands[band].rangehigh);167 *pfreq = freq;168 169 /*170 * For both receiver and transmitter recalculate the signal quality171 * (since that depends on both frequencies) and re-init the rds172 * generator.173 */174 vivid_radio_calc_sig_qual(dev);175 vivid_radio_rds_init(dev);176 return 0;177}178