567 lines
15 KiB
C
567 lines
15 KiB
C
/*
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* vivid-sdr-cap.c - software defined radio support functions.
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*
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* Copyright 2014 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
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*
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* This program is free software; you may redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; version 2 of the License.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
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* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
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* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
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* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
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* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
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* SOFTWARE.
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*/
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#include <linux/errno.h>
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#include <linux/kernel.h>
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#include <linux/delay.h>
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#include <linux/kthread.h>
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#include <linux/freezer.h>
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#include <linux/math64.h>
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#include <linux/videodev2.h>
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#include <linux/v4l2-dv-timings.h>
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#include <media/v4l2-common.h>
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#include <media/v4l2-event.h>
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#include <media/v4l2-dv-timings.h>
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#include <linux/fixp-arith.h>
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#include "vivid-core.h"
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#include "vivid-ctrls.h"
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#include "vivid-sdr-cap.h"
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/* stream formats */
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struct vivid_format {
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u32 pixelformat;
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u32 buffersize;
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};
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/* format descriptions for capture and preview */
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static const struct vivid_format formats[] = {
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{
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.pixelformat = V4L2_SDR_FMT_CU8,
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.buffersize = SDR_CAP_SAMPLES_PER_BUF * 2,
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}, {
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.pixelformat = V4L2_SDR_FMT_CS8,
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.buffersize = SDR_CAP_SAMPLES_PER_BUF * 2,
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},
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};
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static const struct v4l2_frequency_band bands_adc[] = {
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{
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.tuner = 0,
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.type = V4L2_TUNER_ADC,
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.index = 0,
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.capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS,
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.rangelow = 300000,
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.rangehigh = 300000,
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},
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{
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.tuner = 0,
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.type = V4L2_TUNER_ADC,
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.index = 1,
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.capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS,
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.rangelow = 900001,
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.rangehigh = 2800000,
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},
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{
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.tuner = 0,
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.type = V4L2_TUNER_ADC,
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.index = 2,
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.capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS,
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.rangelow = 3200000,
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.rangehigh = 3200000,
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},
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};
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/* ADC band midpoints */
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#define BAND_ADC_0 ((bands_adc[0].rangehigh + bands_adc[1].rangelow) / 2)
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#define BAND_ADC_1 ((bands_adc[1].rangehigh + bands_adc[2].rangelow) / 2)
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static const struct v4l2_frequency_band bands_fm[] = {
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{
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.tuner = 1,
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.type = V4L2_TUNER_RF,
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.index = 0,
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.capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS,
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.rangelow = 50000000,
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.rangehigh = 2000000000,
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},
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};
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static void vivid_thread_sdr_cap_tick(struct vivid_dev *dev)
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{
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struct vivid_buffer *sdr_cap_buf = NULL;
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dprintk(dev, 1, "SDR Capture Thread Tick\n");
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/* Drop a certain percentage of buffers. */
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if (dev->perc_dropped_buffers &&
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prandom_u32_max(100) < dev->perc_dropped_buffers)
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return;
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spin_lock(&dev->slock);
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if (!list_empty(&dev->sdr_cap_active)) {
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sdr_cap_buf = list_entry(dev->sdr_cap_active.next,
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struct vivid_buffer, list);
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list_del(&sdr_cap_buf->list);
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}
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spin_unlock(&dev->slock);
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if (sdr_cap_buf) {
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sdr_cap_buf->vb.sequence = dev->sdr_cap_seq_count;
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vivid_sdr_cap_process(dev, sdr_cap_buf);
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sdr_cap_buf->vb.vb2_buf.timestamp =
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ktime_get_ns() + dev->time_wrap_offset;
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vb2_buffer_done(&sdr_cap_buf->vb.vb2_buf, dev->dqbuf_error ?
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VB2_BUF_STATE_ERROR : VB2_BUF_STATE_DONE);
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dev->dqbuf_error = false;
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}
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}
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static int vivid_thread_sdr_cap(void *data)
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{
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struct vivid_dev *dev = data;
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u64 samples_since_start;
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u64 buffers_since_start;
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u64 next_jiffies_since_start;
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unsigned long jiffies_since_start;
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unsigned long cur_jiffies;
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unsigned wait_jiffies;
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dprintk(dev, 1, "SDR Capture Thread Start\n");
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set_freezable();
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/* Resets frame counters */
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dev->sdr_cap_seq_offset = 0;
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if (dev->seq_wrap)
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dev->sdr_cap_seq_offset = 0xffffff80U;
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dev->jiffies_sdr_cap = jiffies;
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dev->sdr_cap_seq_resync = false;
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for (;;) {
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try_to_freeze();
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if (kthread_should_stop())
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break;
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mutex_lock(&dev->mutex);
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cur_jiffies = jiffies;
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if (dev->sdr_cap_seq_resync) {
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dev->jiffies_sdr_cap = cur_jiffies;
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dev->sdr_cap_seq_offset = dev->sdr_cap_seq_count + 1;
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dev->sdr_cap_seq_count = 0;
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dev->sdr_cap_seq_resync = false;
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}
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/* Calculate the number of jiffies since we started streaming */
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jiffies_since_start = cur_jiffies - dev->jiffies_sdr_cap;
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/* Get the number of buffers streamed since the start */
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buffers_since_start =
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(u64)jiffies_since_start * dev->sdr_adc_freq +
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(HZ * SDR_CAP_SAMPLES_PER_BUF) / 2;
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do_div(buffers_since_start, HZ * SDR_CAP_SAMPLES_PER_BUF);
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/*
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* After more than 0xf0000000 (rounded down to a multiple of
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* 'jiffies-per-day' to ease jiffies_to_msecs calculation)
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* jiffies have passed since we started streaming reset the
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* counters and keep track of the sequence offset.
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*/
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if (jiffies_since_start > JIFFIES_RESYNC) {
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dev->jiffies_sdr_cap = cur_jiffies;
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dev->sdr_cap_seq_offset = buffers_since_start;
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buffers_since_start = 0;
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}
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dev->sdr_cap_seq_count =
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buffers_since_start + dev->sdr_cap_seq_offset;
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vivid_thread_sdr_cap_tick(dev);
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mutex_unlock(&dev->mutex);
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/*
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* Calculate the number of samples streamed since we started,
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* not including the current buffer.
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*/
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samples_since_start = buffers_since_start * SDR_CAP_SAMPLES_PER_BUF;
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/* And the number of jiffies since we started */
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jiffies_since_start = jiffies - dev->jiffies_sdr_cap;
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/* Increase by the number of samples in one buffer */
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samples_since_start += SDR_CAP_SAMPLES_PER_BUF;
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/*
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* Calculate when that next buffer is supposed to start
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* in jiffies since we started streaming.
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*/
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next_jiffies_since_start = samples_since_start * HZ +
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dev->sdr_adc_freq / 2;
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do_div(next_jiffies_since_start, dev->sdr_adc_freq);
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/* If it is in the past, then just schedule asap */
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if (next_jiffies_since_start < jiffies_since_start)
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next_jiffies_since_start = jiffies_since_start;
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wait_jiffies = next_jiffies_since_start - jiffies_since_start;
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schedule_timeout_interruptible(wait_jiffies ? wait_jiffies : 1);
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}
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dprintk(dev, 1, "SDR Capture Thread End\n");
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return 0;
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}
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static int sdr_cap_queue_setup(struct vb2_queue *vq,
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unsigned *nbuffers, unsigned *nplanes,
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unsigned sizes[], struct device *alloc_devs[])
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{
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/* 2 = max 16-bit sample returned */
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sizes[0] = SDR_CAP_SAMPLES_PER_BUF * 2;
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*nplanes = 1;
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return 0;
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}
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static int sdr_cap_buf_prepare(struct vb2_buffer *vb)
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{
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struct vivid_dev *dev = vb2_get_drv_priv(vb->vb2_queue);
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unsigned size = SDR_CAP_SAMPLES_PER_BUF * 2;
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dprintk(dev, 1, "%s\n", __func__);
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if (dev->buf_prepare_error) {
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/*
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* Error injection: test what happens if buf_prepare() returns
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* an error.
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*/
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dev->buf_prepare_error = false;
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return -EINVAL;
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}
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if (vb2_plane_size(vb, 0) < size) {
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dprintk(dev, 1, "%s data will not fit into plane (%lu < %u)\n",
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__func__, vb2_plane_size(vb, 0), size);
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return -EINVAL;
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}
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vb2_set_plane_payload(vb, 0, size);
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return 0;
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}
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static void sdr_cap_buf_queue(struct vb2_buffer *vb)
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{
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struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
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struct vivid_dev *dev = vb2_get_drv_priv(vb->vb2_queue);
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struct vivid_buffer *buf = container_of(vbuf, struct vivid_buffer, vb);
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dprintk(dev, 1, "%s\n", __func__);
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spin_lock(&dev->slock);
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list_add_tail(&buf->list, &dev->sdr_cap_active);
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spin_unlock(&dev->slock);
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}
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static int sdr_cap_start_streaming(struct vb2_queue *vq, unsigned count)
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{
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struct vivid_dev *dev = vb2_get_drv_priv(vq);
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int err = 0;
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dprintk(dev, 1, "%s\n", __func__);
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dev->sdr_cap_seq_count = 0;
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if (dev->start_streaming_error) {
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dev->start_streaming_error = false;
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err = -EINVAL;
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} else if (dev->kthread_sdr_cap == NULL) {
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dev->kthread_sdr_cap = kthread_run(vivid_thread_sdr_cap, dev,
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"%s-sdr-cap", dev->v4l2_dev.name);
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if (IS_ERR(dev->kthread_sdr_cap)) {
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v4l2_err(&dev->v4l2_dev, "kernel_thread() failed\n");
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err = PTR_ERR(dev->kthread_sdr_cap);
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dev->kthread_sdr_cap = NULL;
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}
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}
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if (err) {
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struct vivid_buffer *buf, *tmp;
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list_for_each_entry_safe(buf, tmp, &dev->sdr_cap_active, list) {
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list_del(&buf->list);
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vb2_buffer_done(&buf->vb.vb2_buf,
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VB2_BUF_STATE_QUEUED);
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}
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}
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return err;
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}
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/* abort streaming and wait for last buffer */
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static void sdr_cap_stop_streaming(struct vb2_queue *vq)
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{
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struct vivid_dev *dev = vb2_get_drv_priv(vq);
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if (dev->kthread_sdr_cap == NULL)
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return;
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while (!list_empty(&dev->sdr_cap_active)) {
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struct vivid_buffer *buf;
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buf = list_entry(dev->sdr_cap_active.next,
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struct vivid_buffer, list);
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list_del(&buf->list);
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vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
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}
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/* shutdown control thread */
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mutex_unlock(&dev->mutex);
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kthread_stop(dev->kthread_sdr_cap);
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dev->kthread_sdr_cap = NULL;
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mutex_lock(&dev->mutex);
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}
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const struct vb2_ops vivid_sdr_cap_qops = {
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.queue_setup = sdr_cap_queue_setup,
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.buf_prepare = sdr_cap_buf_prepare,
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.buf_queue = sdr_cap_buf_queue,
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.start_streaming = sdr_cap_start_streaming,
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.stop_streaming = sdr_cap_stop_streaming,
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.wait_prepare = vb2_ops_wait_prepare,
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.wait_finish = vb2_ops_wait_finish,
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};
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int vivid_sdr_enum_freq_bands(struct file *file, void *fh,
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struct v4l2_frequency_band *band)
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{
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switch (band->tuner) {
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case 0:
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if (band->index >= ARRAY_SIZE(bands_adc))
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return -EINVAL;
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*band = bands_adc[band->index];
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return 0;
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case 1:
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if (band->index >= ARRAY_SIZE(bands_fm))
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return -EINVAL;
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*band = bands_fm[band->index];
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return 0;
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default:
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return -EINVAL;
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}
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}
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int vivid_sdr_g_frequency(struct file *file, void *fh,
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struct v4l2_frequency *vf)
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{
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struct vivid_dev *dev = video_drvdata(file);
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switch (vf->tuner) {
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case 0:
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vf->frequency = dev->sdr_adc_freq;
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vf->type = V4L2_TUNER_ADC;
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return 0;
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case 1:
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vf->frequency = dev->sdr_fm_freq;
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vf->type = V4L2_TUNER_RF;
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return 0;
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default:
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return -EINVAL;
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}
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}
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int vivid_sdr_s_frequency(struct file *file, void *fh,
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const struct v4l2_frequency *vf)
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{
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struct vivid_dev *dev = video_drvdata(file);
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unsigned freq = vf->frequency;
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unsigned band;
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switch (vf->tuner) {
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case 0:
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if (vf->type != V4L2_TUNER_ADC)
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return -EINVAL;
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if (freq < BAND_ADC_0)
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band = 0;
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else if (freq < BAND_ADC_1)
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band = 1;
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else
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band = 2;
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freq = clamp_t(unsigned, freq,
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bands_adc[band].rangelow,
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bands_adc[band].rangehigh);
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if (vb2_is_streaming(&dev->vb_sdr_cap_q) &&
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freq != dev->sdr_adc_freq) {
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/* resync the thread's timings */
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dev->sdr_cap_seq_resync = true;
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}
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dev->sdr_adc_freq = freq;
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return 0;
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case 1:
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if (vf->type != V4L2_TUNER_RF)
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return -EINVAL;
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dev->sdr_fm_freq = clamp_t(unsigned, freq,
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bands_fm[0].rangelow,
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bands_fm[0].rangehigh);
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return 0;
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default:
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return -EINVAL;
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}
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}
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int vivid_sdr_g_tuner(struct file *file, void *fh, struct v4l2_tuner *vt)
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{
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switch (vt->index) {
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case 0:
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strlcpy(vt->name, "ADC", sizeof(vt->name));
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vt->type = V4L2_TUNER_ADC;
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vt->capability =
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V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS;
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vt->rangelow = bands_adc[0].rangelow;
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vt->rangehigh = bands_adc[2].rangehigh;
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return 0;
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case 1:
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strlcpy(vt->name, "RF", sizeof(vt->name));
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vt->type = V4L2_TUNER_RF;
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vt->capability =
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V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS;
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vt->rangelow = bands_fm[0].rangelow;
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vt->rangehigh = bands_fm[0].rangehigh;
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return 0;
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default:
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return -EINVAL;
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}
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}
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int vivid_sdr_s_tuner(struct file *file, void *fh, const struct v4l2_tuner *vt)
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{
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if (vt->index > 1)
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return -EINVAL;
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return 0;
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}
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int vidioc_enum_fmt_sdr_cap(struct file *file, void *fh, struct v4l2_fmtdesc *f)
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{
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if (f->index >= ARRAY_SIZE(formats))
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return -EINVAL;
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f->pixelformat = formats[f->index].pixelformat;
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return 0;
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}
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int vidioc_g_fmt_sdr_cap(struct file *file, void *fh, struct v4l2_format *f)
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{
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struct vivid_dev *dev = video_drvdata(file);
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f->fmt.sdr.pixelformat = dev->sdr_pixelformat;
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f->fmt.sdr.buffersize = dev->sdr_buffersize;
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memset(f->fmt.sdr.reserved, 0, sizeof(f->fmt.sdr.reserved));
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return 0;
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}
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int vidioc_s_fmt_sdr_cap(struct file *file, void *fh, struct v4l2_format *f)
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{
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struct vivid_dev *dev = video_drvdata(file);
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struct vb2_queue *q = &dev->vb_sdr_cap_q;
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int i;
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if (vb2_is_busy(q))
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return -EBUSY;
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memset(f->fmt.sdr.reserved, 0, sizeof(f->fmt.sdr.reserved));
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for (i = 0; i < ARRAY_SIZE(formats); i++) {
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if (formats[i].pixelformat == f->fmt.sdr.pixelformat) {
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dev->sdr_pixelformat = formats[i].pixelformat;
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dev->sdr_buffersize = formats[i].buffersize;
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f->fmt.sdr.buffersize = formats[i].buffersize;
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return 0;
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}
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}
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|
dev->sdr_pixelformat = formats[0].pixelformat;
|
|
dev->sdr_buffersize = formats[0].buffersize;
|
|
f->fmt.sdr.pixelformat = formats[0].pixelformat;
|
|
f->fmt.sdr.buffersize = formats[0].buffersize;
|
|
return 0;
|
|
}
|
|
|
|
int vidioc_try_fmt_sdr_cap(struct file *file, void *fh, struct v4l2_format *f)
|
|
{
|
|
int i;
|
|
|
|
memset(f->fmt.sdr.reserved, 0, sizeof(f->fmt.sdr.reserved));
|
|
for (i = 0; i < ARRAY_SIZE(formats); i++) {
|
|
if (formats[i].pixelformat == f->fmt.sdr.pixelformat) {
|
|
f->fmt.sdr.buffersize = formats[i].buffersize;
|
|
return 0;
|
|
}
|
|
}
|
|
f->fmt.sdr.pixelformat = formats[0].pixelformat;
|
|
f->fmt.sdr.buffersize = formats[0].buffersize;
|
|
return 0;
|
|
}
|
|
|
|
#define FIXP_N (15)
|
|
#define FIXP_FRAC (1 << FIXP_N)
|
|
#define FIXP_2PI ((int)(2 * 3.141592653589 * FIXP_FRAC))
|
|
#define M_100000PI (3.14159 * 100000)
|
|
|
|
void vivid_sdr_cap_process(struct vivid_dev *dev, struct vivid_buffer *buf)
|
|
{
|
|
u8 *vbuf = vb2_plane_vaddr(&buf->vb.vb2_buf, 0);
|
|
unsigned long i;
|
|
unsigned long plane_size = vb2_plane_size(&buf->vb.vb2_buf, 0);
|
|
s64 s64tmp;
|
|
s32 src_phase_step;
|
|
s32 mod_phase_step;
|
|
s32 fixp_i;
|
|
s32 fixp_q;
|
|
|
|
/* calculate phase step */
|
|
#define BEEP_FREQ 1000 /* 1kHz beep */
|
|
src_phase_step = DIV_ROUND_CLOSEST(FIXP_2PI * BEEP_FREQ,
|
|
dev->sdr_adc_freq);
|
|
|
|
for (i = 0; i < plane_size; i += 2) {
|
|
mod_phase_step = fixp_cos32_rad(dev->sdr_fixp_src_phase,
|
|
FIXP_2PI) >> (31 - FIXP_N);
|
|
|
|
dev->sdr_fixp_src_phase += src_phase_step;
|
|
s64tmp = (s64) mod_phase_step * dev->sdr_fm_deviation;
|
|
dev->sdr_fixp_mod_phase += div_s64(s64tmp, M_100000PI);
|
|
|
|
/*
|
|
* Transfer phase angle to [0, 2xPI] in order to avoid variable
|
|
* overflow and make it suitable for cosine implementation
|
|
* used, which does not support negative angles.
|
|
*/
|
|
dev->sdr_fixp_src_phase %= FIXP_2PI;
|
|
dev->sdr_fixp_mod_phase %= FIXP_2PI;
|
|
|
|
if (dev->sdr_fixp_mod_phase < 0)
|
|
dev->sdr_fixp_mod_phase += FIXP_2PI;
|
|
|
|
fixp_i = fixp_cos32_rad(dev->sdr_fixp_mod_phase, FIXP_2PI);
|
|
fixp_q = fixp_sin32_rad(dev->sdr_fixp_mod_phase, FIXP_2PI);
|
|
|
|
/* Normalize fraction values represented with 32 bit precision
|
|
* to fixed point representation with FIXP_N bits */
|
|
fixp_i >>= (31 - FIXP_N);
|
|
fixp_q >>= (31 - FIXP_N);
|
|
|
|
switch (dev->sdr_pixelformat) {
|
|
case V4L2_SDR_FMT_CU8:
|
|
/* convert 'fixp float' to u8 [0, +255] */
|
|
/* u8 = X * 127.5 + 127.5; X is float [-1.0, +1.0] */
|
|
fixp_i = fixp_i * 1275 + FIXP_FRAC * 1275;
|
|
fixp_q = fixp_q * 1275 + FIXP_FRAC * 1275;
|
|
*vbuf++ = DIV_ROUND_CLOSEST(fixp_i, FIXP_FRAC * 10);
|
|
*vbuf++ = DIV_ROUND_CLOSEST(fixp_q, FIXP_FRAC * 10);
|
|
break;
|
|
case V4L2_SDR_FMT_CS8:
|
|
/* convert 'fixp float' to s8 [-128, +127] */
|
|
/* s8 = X * 127.5 - 0.5; X is float [-1.0, +1.0] */
|
|
fixp_i = fixp_i * 1275 - FIXP_FRAC * 5;
|
|
fixp_q = fixp_q * 1275 - FIXP_FRAC * 5;
|
|
*vbuf++ = DIV_ROUND_CLOSEST(fixp_i, FIXP_FRAC * 10);
|
|
*vbuf++ = DIV_ROUND_CLOSEST(fixp_q, FIXP_FRAC * 10);
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
}
|
|
}
|