drivers/media/platform/vivid/vivid-sdr-cap.c - kernel/msm-4.19 - Gitiles

 /*
  * vivid-sdr-cap.c - software defined radio support functions.
  *
  * Copyright 2014 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
  *
  * This program is free software; you may redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; version 2 of the License.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
  */

 #include <linux/errno.h>
 #include <linux/kernel.h>
 #include <linux/delay.h>
 #include <linux/kthread.h>
 #include <linux/freezer.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-sdr-cap.h"

 static const struct v4l2_frequency_band bands_adc[] = {
 	{
 		.tuner = 0,
 		.type = V4L2_TUNER_ADC,
 		.index = 0,
 		.capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS,
 		.rangelow   =  300000,
 		.rangehigh  =  300000,
 	},
 	{
 		.tuner = 0,
 		.type = V4L2_TUNER_ADC,
 		.index = 1,
 		.capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS,
 		.rangelow   =  900001,
 		.rangehigh  = 2800000,
 	},
 	{
 		.tuner = 0,
 		.type = V4L2_TUNER_ADC,
 		.index = 2,
 		.capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS,
 		.rangelow   = 3200000,
 		.rangehigh  = 3200000,
 	},
 };

 /* ADC band midpoints */
 #define BAND_ADC_0 ((bands_adc[0].rangehigh + bands_adc[1].rangelow) / 2)
 #define BAND_ADC_1 ((bands_adc[1].rangehigh + bands_adc[2].rangelow) / 2)

 static const struct v4l2_frequency_band bands_fm[] = {
 	{
 		.tuner = 1,
 		.type = V4L2_TUNER_RF,
 		.index = 0,
 		.capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS,
 		.rangelow   =    50000000,
 		.rangehigh  =  2000000000,
 	},
 };

 static void vivid_thread_sdr_cap_tick(struct vivid_dev *dev)
 {
 	struct vivid_buffer *sdr_cap_buf = NULL;

 	dprintk(dev, 1, "SDR Capture Thread Tick\n");

 	/* Drop a certain percentage of buffers. */
 	if (dev->perc_dropped_buffers &&
 	    prandom_u32_max(100) < dev->perc_dropped_buffers)
 		return;

 	spin_lock(&dev->slock);
 	if (!list_empty(&dev->sdr_cap_active)) {
 		sdr_cap_buf = list_entry(dev->sdr_cap_active.next,
 					 struct vivid_buffer, list);
 		list_del(&sdr_cap_buf->list);
 	}
 	spin_unlock(&dev->slock);

 	if (sdr_cap_buf) {
 		sdr_cap_buf->vb.v4l2_buf.sequence = dev->sdr_cap_seq_count;
 		vivid_sdr_cap_process(dev, sdr_cap_buf);
 		v4l2_get_timestamp(&sdr_cap_buf->vb.v4l2_buf.timestamp);
 		sdr_cap_buf->vb.v4l2_buf.timestamp.tv_sec += dev->time_wrap_offset;
 		vb2_buffer_done(&sdr_cap_buf->vb, dev->dqbuf_error ?
 				VB2_BUF_STATE_ERROR : VB2_BUF_STATE_DONE);
 		dev->dqbuf_error = false;
 	}
 }

 static int vivid_thread_sdr_cap(void *data)
 {
 	struct vivid_dev *dev = data;
 	u64 samples_since_start;
 	u64 buffers_since_start;
 	u64 next_jiffies_since_start;
 	unsigned long jiffies_since_start;
 	unsigned long cur_jiffies;
 	unsigned wait_jiffies;

 	dprintk(dev, 1, "SDR Capture Thread Start\n");

 	set_freezable();

 	/* Resets frame counters */
 	dev->sdr_cap_seq_offset = 0;
 	if (dev->seq_wrap)
 		dev->sdr_cap_seq_offset = 0xffffff80U;
 	dev->jiffies_sdr_cap = jiffies;
 	dev->sdr_cap_seq_resync = false;

 	for (;;) {
 		try_to_freeze();
 		if (kthread_should_stop())
 			break;

 		mutex_lock(&dev->mutex);
 		cur_jiffies = jiffies;
 		if (dev->sdr_cap_seq_resync) {
 			dev->jiffies_sdr_cap = cur_jiffies;
 			dev->sdr_cap_seq_offset = dev->sdr_cap_seq_count + 1;
 			dev->sdr_cap_seq_count = 0;
 			dev->sdr_cap_seq_resync = false;
 		}
 		/* Calculate the number of jiffies since we started streaming */
 		jiffies_since_start = cur_jiffies - dev->jiffies_sdr_cap;
 		/* Get the number of buffers streamed since the start */
 		buffers_since_start = (u64)jiffies_since_start * dev->sdr_adc_freq +
 				      (HZ * SDR_CAP_SAMPLES_PER_BUF) / 2;
 		do_div(buffers_since_start, HZ * SDR_CAP_SAMPLES_PER_BUF);

 		/*
 		 * After more than 0xf0000000 (rounded down to a multiple of
 		 * 'jiffies-per-day' to ease jiffies_to_msecs calculation)
 		 * jiffies have passed since we started streaming reset the
 		 * counters and keep track of the sequence offset.
 		 */
 		if (jiffies_since_start > JIFFIES_RESYNC) {
 			dev->jiffies_sdr_cap = cur_jiffies;
 			dev->sdr_cap_seq_offset = buffers_since_start;
 			buffers_since_start = 0;
 		}
 		dev->sdr_cap_seq_count = buffers_since_start + dev->sdr_cap_seq_offset;

 		vivid_thread_sdr_cap_tick(dev);
 		mutex_unlock(&dev->mutex);

 		/*
 		 * Calculate the number of samples streamed since we started,
 		 * not including the current buffer.
 		 */
 		samples_since_start = buffers_since_start * SDR_CAP_SAMPLES_PER_BUF;

 		/* And the number of jiffies since we started */
 		jiffies_since_start = jiffies - dev->jiffies_sdr_cap;

 		/* Increase by the number of samples in one buffer */
 		samples_since_start += SDR_CAP_SAMPLES_PER_BUF;
 		/*
 		 * Calculate when that next buffer is supposed to start
 		 * in jiffies since we started streaming.
 		 */
 		next_jiffies_since_start = samples_since_start * HZ +
 					   dev->sdr_adc_freq / 2;
 		do_div(next_jiffies_since_start, dev->sdr_adc_freq);
 		/* If it is in the past, then just schedule asap */
 		if (next_jiffies_since_start < jiffies_since_start)
 			next_jiffies_since_start = jiffies_since_start;

 		wait_jiffies = next_jiffies_since_start - jiffies_since_start;
 		schedule_timeout_interruptible(wait_jiffies ? wait_jiffies : 1);
 	}
 	dprintk(dev, 1, "SDR Capture Thread End\n");
 	return 0;
 }

 static int sdr_cap_queue_setup(struct vb2_queue *vq, const struct v4l2_format *fmt,
 		       unsigned *nbuffers, unsigned *nplanes,
 		       unsigned sizes[], void *alloc_ctxs[])
 {
 	/* 2 = max 16-bit sample returned */
 	sizes[0] = SDR_CAP_SAMPLES_PER_BUF * 2;
 	*nplanes = 1;
 	return 0;
 }

 static int sdr_cap_buf_prepare(struct vb2_buffer *vb)
 {
 	struct vivid_dev *dev = vb2_get_drv_priv(vb->vb2_queue);
 	unsigned size = SDR_CAP_SAMPLES_PER_BUF * 2;

 	dprintk(dev, 1, "%s\n", __func__);

 	if (dev->buf_prepare_error) {
 		/*
 		 * Error injection: test what happens if buf_prepare() returns
 		 * an error.
 		 */
 		dev->buf_prepare_error = false;
 		return -EINVAL;
 	}
 	if (vb2_plane_size(vb, 0) < size) {
 		dprintk(dev, 1, "%s data will not fit into plane (%lu < %u)\n",
 				__func__, vb2_plane_size(vb, 0), size);
 		return -EINVAL;
 	}
 	vb2_set_plane_payload(vb, 0, size);

 	return 0;
 }

 static void sdr_cap_buf_queue(struct vb2_buffer *vb)
 {
 	struct vivid_dev *dev = vb2_get_drv_priv(vb->vb2_queue);
 	struct vivid_buffer *buf = container_of(vb, struct vivid_buffer, vb);

 	dprintk(dev, 1, "%s\n", __func__);

 	spin_lock(&dev->slock);
 	list_add_tail(&buf->list, &dev->sdr_cap_active);
 	spin_unlock(&dev->slock);
 }

 static int sdr_cap_start_streaming(struct vb2_queue *vq, unsigned count)
 {
 	struct vivid_dev *dev = vb2_get_drv_priv(vq);
 	int err = 0;

 	dprintk(dev, 1, "%s\n", __func__);
 	dev->sdr_cap_seq_count = 0;
 	if (dev->start_streaming_error) {
 		dev->start_streaming_error = false;
 		err = -EINVAL;
 	} else if (dev->kthread_sdr_cap == NULL) {
 		dev->kthread_sdr_cap = kthread_run(vivid_thread_sdr_cap, dev,
 				"%s-sdr-cap", dev->v4l2_dev.name);

 		if (IS_ERR(dev->kthread_sdr_cap)) {
 			v4l2_err(&dev->v4l2_dev, "kernel_thread() failed\n");
 			err = PTR_ERR(dev->kthread_sdr_cap);
 			dev->kthread_sdr_cap = NULL;
 		}
 	}
 	if (err) {
 		struct vivid_buffer *buf, *tmp;

 		list_for_each_entry_safe(buf, tmp, &dev->sdr_cap_active, list) {
 			list_del(&buf->list);
 			vb2_buffer_done(&buf->vb, VB2_BUF_STATE_QUEUED);
 		}
 	}
 	return err;
 }

 /* abort streaming and wait for last buffer */
 static void sdr_cap_stop_streaming(struct vb2_queue *vq)
 {
 	struct vivid_dev *dev = vb2_get_drv_priv(vq);

 	if (dev->kthread_sdr_cap == NULL)
 		return;

 	while (!list_empty(&dev->sdr_cap_active)) {
 		struct vivid_buffer *buf;

 		buf = list_entry(dev->sdr_cap_active.next, struct vivid_buffer, list);
 		list_del(&buf->list);
 		vb2_buffer_done(&buf->vb, VB2_BUF_STATE_ERROR);
 	}

 	/* shutdown control thread */
 	mutex_unlock(&dev->mutex);
 	kthread_stop(dev->kthread_sdr_cap);
 	dev->kthread_sdr_cap = NULL;
 	mutex_lock(&dev->mutex);
 }

 const struct vb2_ops vivid_sdr_cap_qops = {
 	.queue_setup		= sdr_cap_queue_setup,
 	.buf_prepare		= sdr_cap_buf_prepare,
 	.buf_queue		= sdr_cap_buf_queue,
 	.start_streaming	= sdr_cap_start_streaming,
 	.stop_streaming		= sdr_cap_stop_streaming,
 	.wait_prepare		= vb2_ops_wait_prepare,
 	.wait_finish		= vb2_ops_wait_finish,
 };

 int vivid_sdr_enum_freq_bands(struct file *file, void *fh, struct v4l2_frequency_band *band)
 {
 	switch (band->tuner) {
 	case 0:
 		if (band->index >= ARRAY_SIZE(bands_adc))
 			return -EINVAL;
 		*band = bands_adc[band->index];
 		return 0;
 	case 1:
 		if (band->index >= ARRAY_SIZE(bands_fm))
 			return -EINVAL;
 		*band = bands_fm[band->index];
 		return 0;
 	default:
 		return -EINVAL;
 	}
 }

 int vivid_sdr_g_frequency(struct file *file, void *fh, struct v4l2_frequency *vf)
 {
 	struct vivid_dev *dev = video_drvdata(file);

 	switch (vf->tuner) {
 	case 0:
 		vf->frequency = dev->sdr_adc_freq;
 		vf->type = V4L2_TUNER_ADC;
 		return 0;
 	case 1:
 		vf->frequency = dev->sdr_fm_freq;
 		vf->type = V4L2_TUNER_RF;
 		return 0;
 	default:
 		return -EINVAL;
 	}
 }

 int vivid_sdr_s_frequency(struct file *file, void *fh, const struct v4l2_frequency *vf)
 {
 	struct vivid_dev *dev = video_drvdata(file);
 	unsigned freq = vf->frequency;
 	unsigned band;

 	switch (vf->tuner) {
 	case 0:
 		if (vf->type != V4L2_TUNER_ADC)
 			return -EINVAL;
 		if (freq < BAND_ADC_0)
 			band = 0;
 		else if (freq < BAND_ADC_1)
 			band = 1;
 		else
 			band = 2;

 		freq = clamp_t(unsigned, freq,
 				bands_adc[band].rangelow,
 				bands_adc[band].rangehigh);

 		if (vb2_is_streaming(&dev->vb_sdr_cap_q) &&
 		    freq != dev->sdr_adc_freq) {
 			/* resync the thread's timings */
 			dev->sdr_cap_seq_resync = true;
 		}
 		dev->sdr_adc_freq = freq;
 		return 0;
 	case 1:
 		if (vf->type != V4L2_TUNER_RF)
 			return -EINVAL;
 		dev->sdr_fm_freq = clamp_t(unsigned, freq,
 				bands_fm[0].rangelow,
 				bands_fm[0].rangehigh);
 		return 0;
 	default:
 		return -EINVAL;
 	}
 }

 int vivid_sdr_g_tuner(struct file *file, void *fh, struct v4l2_tuner *vt)
 {
 	switch (vt->index) {
 	case 0:
 		strlcpy(vt->name, "ADC", sizeof(vt->name));
 		vt->type = V4L2_TUNER_ADC;
 		vt->capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS;
 		vt->rangelow = bands_adc[0].rangelow;
 		vt->rangehigh = bands_adc[2].rangehigh;
 		return 0;
 	case 1:
 		strlcpy(vt->name, "RF", sizeof(vt->name));
 		vt->type = V4L2_TUNER_RF;
 		vt->capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS;
 		vt->rangelow = bands_fm[0].rangelow;
 		vt->rangehigh = bands_fm[0].rangehigh;
 		return 0;
 	default:
 		return -EINVAL;
 	}
 }

 int vivid_sdr_s_tuner(struct file *file, void *fh, const struct v4l2_tuner *vt)
 {
 	if (vt->index > 1)
 		return -EINVAL;
 	return 0;
 }

 int vidioc_enum_fmt_sdr_cap(struct file *file, void *fh, struct v4l2_fmtdesc *f)
 {
 	if (f->index)
 		return -EINVAL;
 	f->pixelformat = V4L2_SDR_FMT_CU8;
 	strlcpy(f->description, "IQ U8", sizeof(f->description));
 	return 0;
 }

 int vidioc_g_fmt_sdr_cap(struct file *file, void *fh, struct v4l2_format *f)
 {
 	f->fmt.sdr.pixelformat = V4L2_SDR_FMT_CU8;
 	f->fmt.sdr.buffersize = SDR_CAP_SAMPLES_PER_BUF * 2;
 	memset(f->fmt.sdr.reserved, 0, sizeof(f->fmt.sdr.reserved));
 	return 0;
 }

 #define FIXP_FRAC    (1 << 15)
 #define FIXP_PI      ((int)(FIXP_FRAC * 3.141592653589))

 /* cos() from cx88 driver: cx88-dsp.c */
 static s32 fixp_cos(unsigned int x)
 {
 	u32 t2, t4, t6, t8;
 	u16 period = x / FIXP_PI;

 	if (period % 2)
 		return -fixp_cos(x - FIXP_PI);
 	x = x % FIXP_PI;
 	if (x > FIXP_PI/2)
 		return -fixp_cos(FIXP_PI/2 - (x % (FIXP_PI/2)));
 	/* Now x is between 0 and FIXP_PI/2.
 	 * To calculate cos(x) we use it's Taylor polinom. */
 	t2 = x*x/FIXP_FRAC/2;
 	t4 = t2*x/FIXP_FRAC*x/FIXP_FRAC/3/4;
 	t6 = t4*x/FIXP_FRAC*x/FIXP_FRAC/5/6;
 	t8 = t6*x/FIXP_FRAC*x/FIXP_FRAC/7/8;
 	return FIXP_FRAC-t2+t4-t6+t8;
 }

 static inline s32 fixp_sin(unsigned int x)
 {
 	return -fixp_cos(x + (FIXP_PI / 2));
 }

 void vivid_sdr_cap_process(struct vivid_dev *dev, struct vivid_buffer *buf)
 {
 	u8 *vbuf = vb2_plane_vaddr(&buf->vb, 0);
 	unsigned long i;
 	unsigned long plane_size = vb2_plane_size(&buf->vb, 0);
 	int fixp_src_phase_step, fixp_i, fixp_q;

 	/*
 	 * TODO: Generated beep tone goes very crackly when sample rate is
 	 * increased to ~1Msps or more. That is because of huge rounding error
 	 * of phase angle caused by used cosine implementation.
 	 */

 	/* calculate phase step */
 	#define BEEP_FREQ 1000 /* 1kHz beep */
 	fixp_src_phase_step = DIV_ROUND_CLOSEST(2 * FIXP_PI * BEEP_FREQ,
 			dev->sdr_adc_freq);

 	for (i = 0; i < plane_size; i += 2) {
 		dev->sdr_fixp_mod_phase += fixp_cos(dev->sdr_fixp_src_phase);
 		dev->sdr_fixp_src_phase += fixp_src_phase_step;

 		/*
 		 * Transfer phases to [0 / 2xPI] in order to avoid variable
 		 * overflow and make it suitable for cosine implementation
 		 * used, which does not support negative angles.
 		 */
 		while (dev->sdr_fixp_mod_phase < (0 * FIXP_PI))
 			dev->sdr_fixp_mod_phase += (2 * FIXP_PI);
 		while (dev->sdr_fixp_mod_phase > (2 * FIXP_PI))
 			dev->sdr_fixp_mod_phase -= (2 * FIXP_PI);

 		while (dev->sdr_fixp_src_phase > (2 * FIXP_PI))
 			dev->sdr_fixp_src_phase -= (2 * FIXP_PI);

 		fixp_i = fixp_cos(dev->sdr_fixp_mod_phase);
 		fixp_q = fixp_sin(dev->sdr_fixp_mod_phase);

 		/* convert 'fixp float' to u8 */
 		/* u8 = X * 127.5f + 127.5f; where 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);
 	}
 }
	/*
	* vivid-sdr-cap.c - software defined radio support functions.
	*
	* Copyright 2014 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
	*
	* This program is free software; you may redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; version 2 of the License.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
	* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
	* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
	* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
	* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
	* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
	* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
	* SOFTWARE.
	*/

	#include <linux/errno.h>
	#include <linux/kernel.h>
	#include <linux/delay.h>
	#include <linux/kthread.h>
	#include <linux/freezer.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-sdr-cap.h"

	static const struct v4l2_frequency_band bands_adc[] = {
	{
	.tuner = 0,
	.type = V4L2_TUNER_ADC,
	.index = 0,
	.capability = V4L2_TUNER_CAP_1HZ \| V4L2_TUNER_CAP_FREQ_BANDS,
	.rangelow = 300000,
	.rangehigh = 300000,
	},
	{
	.tuner = 0,
	.type = V4L2_TUNER_ADC,
	.index = 1,
	.capability = V4L2_TUNER_CAP_1HZ \| V4L2_TUNER_CAP_FREQ_BANDS,
	.rangelow = 900001,
	.rangehigh = 2800000,
	},
	{
	.tuner = 0,
	.type = V4L2_TUNER_ADC,
	.index = 2,
	.capability = V4L2_TUNER_CAP_1HZ \| V4L2_TUNER_CAP_FREQ_BANDS,
	.rangelow = 3200000,
	.rangehigh = 3200000,
	},
	};

	/* ADC band midpoints */
	#define BAND_ADC_0 ((bands_adc[0].rangehigh + bands_adc[1].rangelow) / 2)
	#define BAND_ADC_1 ((bands_adc[1].rangehigh + bands_adc[2].rangelow) / 2)

	static const struct v4l2_frequency_band bands_fm[] = {
	{
	.tuner = 1,
	.type = V4L2_TUNER_RF,
	.index = 0,
	.capability = V4L2_TUNER_CAP_1HZ \| V4L2_TUNER_CAP_FREQ_BANDS,
	.rangelow = 50000000,
	.rangehigh = 2000000000,
	},
	};

	static void vivid_thread_sdr_cap_tick(struct vivid_dev *dev)
	{
	struct vivid_buffer *sdr_cap_buf = NULL;

	dprintk(dev, 1, "SDR Capture Thread Tick\n");

	/* Drop a certain percentage of buffers. */
	if (dev->perc_dropped_buffers &&
	prandom_u32_max(100) < dev->perc_dropped_buffers)
	return;

	spin_lock(&dev->slock);
	if (!list_empty(&dev->sdr_cap_active)) {
	sdr_cap_buf = list_entry(dev->sdr_cap_active.next,
	struct vivid_buffer, list);
	list_del(&sdr_cap_buf->list);
	}
	spin_unlock(&dev->slock);

	if (sdr_cap_buf) {
	sdr_cap_buf->vb.v4l2_buf.sequence = dev->sdr_cap_seq_count;
	vivid_sdr_cap_process(dev, sdr_cap_buf);
	v4l2_get_timestamp(&sdr_cap_buf->vb.v4l2_buf.timestamp);
	sdr_cap_buf->vb.v4l2_buf.timestamp.tv_sec += dev->time_wrap_offset;
	vb2_buffer_done(&sdr_cap_buf->vb, dev->dqbuf_error ?
	VB2_BUF_STATE_ERROR : VB2_BUF_STATE_DONE);
	dev->dqbuf_error = false;
	}
	}

	static int vivid_thread_sdr_cap(void *data)
	{
	struct vivid_dev *dev = data;
	u64 samples_since_start;
	u64 buffers_since_start;
	u64 next_jiffies_since_start;
	unsigned long jiffies_since_start;
	unsigned long cur_jiffies;
	unsigned wait_jiffies;

	dprintk(dev, 1, "SDR Capture Thread Start\n");

	set_freezable();

	/* Resets frame counters */
	dev->sdr_cap_seq_offset = 0;
	if (dev->seq_wrap)
	dev->sdr_cap_seq_offset = 0xffffff80U;
	dev->jiffies_sdr_cap = jiffies;
	dev->sdr_cap_seq_resync = false;

	for (;;) {
	try_to_freeze();
	if (kthread_should_stop())
	break;

	mutex_lock(&dev->mutex);
	cur_jiffies = jiffies;
	if (dev->sdr_cap_seq_resync) {
	dev->jiffies_sdr_cap = cur_jiffies;
	dev->sdr_cap_seq_offset = dev->sdr_cap_seq_count + 1;
	dev->sdr_cap_seq_count = 0;
	dev->sdr_cap_seq_resync = false;
	}
	/* Calculate the number of jiffies since we started streaming */
	jiffies_since_start = cur_jiffies - dev->jiffies_sdr_cap;
	/* Get the number of buffers streamed since the start */
	buffers_since_start = (u64)jiffies_since_start * dev->sdr_adc_freq +
	(HZ * SDR_CAP_SAMPLES_PER_BUF) / 2;
	do_div(buffers_since_start, HZ * SDR_CAP_SAMPLES_PER_BUF);

	/*
	* After more than 0xf0000000 (rounded down to a multiple of
	* 'jiffies-per-day' to ease jiffies_to_msecs calculation)
	* jiffies have passed since we started streaming reset the
	* counters and keep track of the sequence offset.
	*/
	if (jiffies_since_start > JIFFIES_RESYNC) {
	dev->jiffies_sdr_cap = cur_jiffies;
	dev->sdr_cap_seq_offset = buffers_since_start;
	buffers_since_start = 0;
	}
	dev->sdr_cap_seq_count = buffers_since_start + dev->sdr_cap_seq_offset;

	vivid_thread_sdr_cap_tick(dev);
	mutex_unlock(&dev->mutex);

	/*
	* Calculate the number of samples streamed since we started,
	* not including the current buffer.
	*/
	samples_since_start = buffers_since_start * SDR_CAP_SAMPLES_PER_BUF;

	/* And the number of jiffies since we started */
	jiffies_since_start = jiffies - dev->jiffies_sdr_cap;

	/* Increase by the number of samples in one buffer */
	samples_since_start += SDR_CAP_SAMPLES_PER_BUF;
	/*
	* Calculate when that next buffer is supposed to start
	* in jiffies since we started streaming.
	*/
	next_jiffies_since_start = samples_since_start * HZ +
	dev->sdr_adc_freq / 2;
	do_div(next_jiffies_since_start, dev->sdr_adc_freq);
	/* If it is in the past, then just schedule asap */
	if (next_jiffies_since_start < jiffies_since_start)
	next_jiffies_since_start = jiffies_since_start;

	wait_jiffies = next_jiffies_since_start - jiffies_since_start;
	schedule_timeout_interruptible(wait_jiffies ? wait_jiffies : 1);
	}
	dprintk(dev, 1, "SDR Capture Thread End\n");
	return 0;
	}

	static int sdr_cap_queue_setup(struct vb2_queue vq, const struct v4l2_format fmt,
	unsigned nbuffers, unsigned nplanes,
	unsigned sizes[], void *alloc_ctxs[])
	{
	/* 2 = max 16-bit sample returned */
	sizes[0] = SDR_CAP_SAMPLES_PER_BUF * 2;
	*nplanes = 1;
	return 0;
	}

	static int sdr_cap_buf_prepare(struct vb2_buffer *vb)
	{
	struct vivid_dev *dev = vb2_get_drv_priv(vb->vb2_queue);
	unsigned size = SDR_CAP_SAMPLES_PER_BUF * 2;

	dprintk(dev, 1, "%s\n", __func__);

	if (dev->buf_prepare_error) {
	/*
	* Error injection: test what happens if buf_prepare() returns
	* an error.
	*/
	dev->buf_prepare_error = false;
	return -EINVAL;
	}
	if (vb2_plane_size(vb, 0) < size) {
	dprintk(dev, 1, "%s data will not fit into plane (%lu < %u)\n",
	__func__, vb2_plane_size(vb, 0), size);
	return -EINVAL;
	}
	vb2_set_plane_payload(vb, 0, size);

	return 0;
	}

	static void sdr_cap_buf_queue(struct vb2_buffer *vb)
	{
	struct vivid_dev *dev = vb2_get_drv_priv(vb->vb2_queue);
	struct vivid_buffer *buf = container_of(vb, struct vivid_buffer, vb);

	dprintk(dev, 1, "%s\n", __func__);

	spin_lock(&dev->slock);
	list_add_tail(&buf->list, &dev->sdr_cap_active);
	spin_unlock(&dev->slock);
	}

	static int sdr_cap_start_streaming(struct vb2_queue *vq, unsigned count)
	{
	struct vivid_dev *dev = vb2_get_drv_priv(vq);
	int err = 0;

	dprintk(dev, 1, "%s\n", __func__);
	dev->sdr_cap_seq_count = 0;
	if (dev->start_streaming_error) {
	dev->start_streaming_error = false;
	err = -EINVAL;
	} else if (dev->kthread_sdr_cap == NULL) {
	dev->kthread_sdr_cap = kthread_run(vivid_thread_sdr_cap, dev,
	"%s-sdr-cap", dev->v4l2_dev.name);

	if (IS_ERR(dev->kthread_sdr_cap)) {
	v4l2_err(&dev->v4l2_dev, "kernel_thread() failed\n");
	err = PTR_ERR(dev->kthread_sdr_cap);
	dev->kthread_sdr_cap = NULL;
	}
	}
	if (err) {
	struct vivid_buffer buf, tmp;

	list_for_each_entry_safe(buf, tmp, &dev->sdr_cap_active, list) {
	list_del(&buf->list);
	vb2_buffer_done(&buf->vb, VB2_BUF_STATE_QUEUED);
	}
	}
	return err;
	}

	/* abort streaming and wait for last buffer */
	static void sdr_cap_stop_streaming(struct vb2_queue *vq)
	{
	struct vivid_dev *dev = vb2_get_drv_priv(vq);

	if (dev->kthread_sdr_cap == NULL)
	return;

	while (!list_empty(&dev->sdr_cap_active)) {
	struct vivid_buffer *buf;

	buf = list_entry(dev->sdr_cap_active.next, struct vivid_buffer, list);
	list_del(&buf->list);
	vb2_buffer_done(&buf->vb, VB2_BUF_STATE_ERROR);
	}

	/* shutdown control thread */
	mutex_unlock(&dev->mutex);
	kthread_stop(dev->kthread_sdr_cap);
	dev->kthread_sdr_cap = NULL;
	mutex_lock(&dev->mutex);
	}

	const struct vb2_ops vivid_sdr_cap_qops = {
	.queue_setup = sdr_cap_queue_setup,
	.buf_prepare = sdr_cap_buf_prepare,
	.buf_queue = sdr_cap_buf_queue,
	.start_streaming = sdr_cap_start_streaming,
	.stop_streaming = sdr_cap_stop_streaming,
	.wait_prepare = vb2_ops_wait_prepare,
	.wait_finish = vb2_ops_wait_finish,
	};

	int vivid_sdr_enum_freq_bands(struct file file, void fh, struct v4l2_frequency_band *band)
	{
	switch (band->tuner) {
	case 0:
	if (band->index >= ARRAY_SIZE(bands_adc))
	return -EINVAL;
	*band = bands_adc[band->index];
	return 0;
	case 1:
	if (band->index >= ARRAY_SIZE(bands_fm))
	return -EINVAL;
	*band = bands_fm[band->index];
	return 0;
	default:
	return -EINVAL;
	}
	}

	int vivid_sdr_g_frequency(struct file file, void fh, struct v4l2_frequency *vf)
	{
	struct vivid_dev *dev = video_drvdata(file);

	switch (vf->tuner) {
	case 0:
	vf->frequency = dev->sdr_adc_freq;
	vf->type = V4L2_TUNER_ADC;
	return 0;
	case 1:
	vf->frequency = dev->sdr_fm_freq;
	vf->type = V4L2_TUNER_RF;
	return 0;
	default:
	return -EINVAL;
	}
	}

	int vivid_sdr_s_frequency(struct file file, void fh, const struct v4l2_frequency *vf)
	{
	struct vivid_dev *dev = video_drvdata(file);
	unsigned freq = vf->frequency;
	unsigned band;

	switch (vf->tuner) {
	case 0:
	if (vf->type != V4L2_TUNER_ADC)
	return -EINVAL;
	if (freq < BAND_ADC_0)
	band = 0;
	else if (freq < BAND_ADC_1)
	band = 1;
	else
	band = 2;

	freq = clamp_t(unsigned, freq,
	bands_adc[band].rangelow,
	bands_adc[band].rangehigh);

	if (vb2_is_streaming(&dev->vb_sdr_cap_q) &&
	freq != dev->sdr_adc_freq) {
	/* resync the thread's timings */
	dev->sdr_cap_seq_resync = true;
	}
	dev->sdr_adc_freq = freq;
	return 0;
	case 1:
	if (vf->type != V4L2_TUNER_RF)
	return -EINVAL;
	dev->sdr_fm_freq = clamp_t(unsigned, freq,
	bands_fm[0].rangelow,
	bands_fm[0].rangehigh);
	return 0;
	default:
	return -EINVAL;
	}
	}

	int vivid_sdr_g_tuner(struct file file, void fh, struct v4l2_tuner *vt)
	{
	switch (vt->index) {
	case 0:
	strlcpy(vt->name, "ADC", sizeof(vt->name));
	vt->type = V4L2_TUNER_ADC;
	vt->capability = V4L2_TUNER_CAP_1HZ \| V4L2_TUNER_CAP_FREQ_BANDS;
	vt->rangelow = bands_adc[0].rangelow;
	vt->rangehigh = bands_adc[2].rangehigh;
	return 0;
	case 1:
	strlcpy(vt->name, "RF", sizeof(vt->name));
	vt->type = V4L2_TUNER_RF;
	vt->capability = V4L2_TUNER_CAP_1HZ \| V4L2_TUNER_CAP_FREQ_BANDS;
	vt->rangelow = bands_fm[0].rangelow;
	vt->rangehigh = bands_fm[0].rangehigh;
	return 0;
	default:
	return -EINVAL;
	}
	}

	int vivid_sdr_s_tuner(struct file file, void fh, const struct v4l2_tuner *vt)
	{
	if (vt->index > 1)
	return -EINVAL;
	return 0;
	}

	int vidioc_enum_fmt_sdr_cap(struct file file, void fh, struct v4l2_fmtdesc *f)
	{
	if (f->index)
	return -EINVAL;
	f->pixelformat = V4L2_SDR_FMT_CU8;
	strlcpy(f->description, "IQ U8", sizeof(f->description));
	return 0;
	}

	int vidioc_g_fmt_sdr_cap(struct file file, void fh, struct v4l2_format *f)
	{
	f->fmt.sdr.pixelformat = V4L2_SDR_FMT_CU8;
	f->fmt.sdr.buffersize = SDR_CAP_SAMPLES_PER_BUF * 2;
	memset(f->fmt.sdr.reserved, 0, sizeof(f->fmt.sdr.reserved));
	return 0;
	}

	#define FIXP_FRAC (1 << 15)
	#define FIXP_PI ((int)(FIXP_FRAC * 3.141592653589))

	/* cos() from cx88 driver: cx88-dsp.c */
	static s32 fixp_cos(unsigned int x)
	{
	u32 t2, t4, t6, t8;
	u16 period = x / FIXP_PI;

	if (period % 2)
	return -fixp_cos(x - FIXP_PI);
	x = x % FIXP_PI;
	if (x > FIXP_PI/2)
	return -fixp_cos(FIXP_PI/2 - (x % (FIXP_PI/2)));
	/* Now x is between 0 and FIXP_PI/2.
	* To calculate cos(x) we use it's Taylor polinom. */
	t2 = x*x/FIXP_FRAC/2;
	t4 = t2x/FIXP_FRACx/FIXP_FRAC/3/4;
	t6 = t4x/FIXP_FRACx/FIXP_FRAC/5/6;
	t8 = t6x/FIXP_FRACx/FIXP_FRAC/7/8;
	return FIXP_FRAC-t2+t4-t6+t8;
	}

	static inline s32 fixp_sin(unsigned int x)
	{
	return -fixp_cos(x + (FIXP_PI / 2));
	}

	void vivid_sdr_cap_process(struct vivid_dev dev, struct vivid_buffer buf)
	{
	u8 *vbuf = vb2_plane_vaddr(&buf->vb, 0);
	unsigned long i;
	unsigned long plane_size = vb2_plane_size(&buf->vb, 0);
	int fixp_src_phase_step, fixp_i, fixp_q;

	/*
	* TODO: Generated beep tone goes very crackly when sample rate is
	* increased to ~1Msps or more. That is because of huge rounding error
	* of phase angle caused by used cosine implementation.
	*/

	/* calculate phase step */
	#define BEEP_FREQ 1000 /* 1kHz beep */
	fixp_src_phase_step = DIV_ROUND_CLOSEST(2 * FIXP_PI * BEEP_FREQ,
	dev->sdr_adc_freq);

	for (i = 0; i < plane_size; i += 2) {
	dev->sdr_fixp_mod_phase += fixp_cos(dev->sdr_fixp_src_phase);
	dev->sdr_fixp_src_phase += fixp_src_phase_step;

	/*
	* Transfer phases to [0 / 2xPI] in order to avoid variable
	* overflow and make it suitable for cosine implementation
	* used, which does not support negative angles.
	*/
	while (dev->sdr_fixp_mod_phase < (0 * FIXP_PI))
	dev->sdr_fixp_mod_phase += (2 * FIXP_PI);
	while (dev->sdr_fixp_mod_phase > (2 * FIXP_PI))
	dev->sdr_fixp_mod_phase -= (2 * FIXP_PI);

	while (dev->sdr_fixp_src_phase > (2 * FIXP_PI))
	dev->sdr_fixp_src_phase -= (2 * FIXP_PI);

	fixp_i = fixp_cos(dev->sdr_fixp_mod_phase);
	fixp_q = fixp_sin(dev->sdr_fixp_mod_phase);

	/* convert 'fixp float' to u8 */
	/* u8 = X * 127.5f + 127.5f; where 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);
	}
	}