blob: 4af55f18829f78eb640d2677d6535cfb387a291a [file] [log] [blame]
/*
* 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);
}
}