From: Hans Verkuil <hans.verkuil@xxxxxxxxx>
This adds support for an SDR capture device. It generates simple
sine/cosine waves. The code for that has been contributed by
Antti.
Signed-off-by: Antti Palosaari <crope@xxxxxx>
Signed-off-by: Hans Verkuil <hans.verkuil@xxxxxxxxx>
---
drivers/media/platform/vivid/vivid-sdr-cap.c | 499 +++++++++++++++++++++++++++
drivers/media/platform/vivid/vivid-sdr-cap.h | 34 ++
2 files changed, 533 insertions(+)
create mode 100644 drivers/media/platform/vivid/vivid-sdr-cap.c
create mode 100644 drivers/media/platform/vivid/vivid-sdr-cap.h
diff --git a/drivers/media/platform/vivid/vivid-sdr-cap.c b/drivers/media/platform/vivid/vivid-sdr-cap.c
new file mode 100644
index 0000000..8c5d661
--- /dev/null
+++ b/drivers/media/platform/vivid/vivid-sdr-cap.c
@@ -0,0 +1,499 @@
+/*
+ * 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 = vivid_unlock,
+ .wait_finish = vivid_lock,
+};
+
+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);
+ }
+}
diff --git a/drivers/media/platform/vivid/vivid-sdr-cap.h b/drivers/media/platform/vivid/vivid-sdr-cap.h
new file mode 100644
index 0000000..79c1890
--- /dev/null
+++ b/drivers/media/platform/vivid/vivid-sdr-cap.h
@@ -0,0 +1,34 @@
+/*
+ * vivid-sdr-cap.h - 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.
+ */
+
+#ifndef _VIVID_SDR_CAP_H_
+#define _VIVID_SDR_CAP_H_
+
+int vivid_sdr_enum_freq_bands(struct file *file, void *fh, struct v4l2_frequency_band *band);
+int vivid_sdr_g_frequency(struct file *file, void *fh, struct v4l2_frequency *vf);
+int vivid_sdr_s_frequency(struct file *file, void *fh, const struct v4l2_frequency *vf);
+int vivid_sdr_g_tuner(struct file *file, void *fh, struct v4l2_tuner *vt);
+int vivid_sdr_s_tuner(struct file *file, void *fh, const struct v4l2_tuner *vt);
+int vidioc_enum_fmt_sdr_cap(struct file *file, void *fh, struct v4l2_fmtdesc *f);
+int vidioc_g_fmt_sdr_cap(struct file *file, void *fh, struct v4l2_format *f);
+void vivid_sdr_cap_process(struct vivid_dev *dev, struct vivid_buffer *buf);
+
+extern const struct vb2_ops vivid_sdr_cap_qops;
+
+#endif
--
2.0.1
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