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-rw-r--r--c_sources/libosmo-fl2k.c1117
-rw-r--r--c_sources/osmo-fl2k.h163
-rw-r--r--c_sources/osmo-fl2k_export.h51
3 files changed, 1331 insertions, 0 deletions
diff --git a/c_sources/libosmo-fl2k.c b/c_sources/libosmo-fl2k.c
new file mode 100644
index 0000000..99dcd33
--- /dev/null
+++ b/c_sources/libosmo-fl2k.c
@@ -0,0 +1,1117 @@
+/*
+ * osmo-fl2k, turns FL2000-based USB 3.0 to VGA adapters into
+ * low cost DACs
+ *
+ * Copyright (C) 2016-2020 by Steve Markgraf <steve@steve-m.de>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <errno.h>
+#include <signal.h>
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+#include <libusb.h>
+#include <pthread.h>
+
+#ifndef _WIN32
+#include <unistd.h>
+#define sleep_ms(ms) usleep(ms*1000)
+#else
+#include <windows.h>
+#define sleep_ms(ms) Sleep(ms)
+#endif
+
+/*
+ * All libusb callback functions should be marked with the LIBUSB_CALL macro
+ * to ensure that they are compiled with the same calling convention as libusb.
+ *
+ * If the macro isn't available in older libusb versions, we simply define it.
+ */
+#ifndef LIBUSB_CALL
+#define LIBUSB_CALL
+#endif
+
+/* libusb < 1.0.9 doesn't have libusb_handle_events_timeout_completed */
+#ifndef HAVE_LIBUSB_HANDLE_EVENTS_TIMEOUT_COMPLETED
+#define libusb_handle_events_timeout_completed(ctx, tv, c) \
+ libusb_handle_events_timeout(ctx, tv)
+#endif
+
+#include "osmo-fl2k.h"
+
+enum fl2k_async_status {
+ FL2K_INACTIVE = 0,
+ FL2K_CANCELING,
+ FL2K_RUNNING
+};
+
+typedef enum fl2k_buf_state {
+ BUF_EMPTY = 0,
+ BUF_SUBMITTED,
+ BUF_FILLED,
+} fl2k_buf_state_t;
+
+typedef struct fl2k_xfer_info {
+ fl2k_dev_t *dev;
+ uint64_t seq;
+ fl2k_buf_state_t state;
+} fl2k_xfer_info_t;
+
+struct fl2k_dev {
+ libusb_context *ctx;
+ struct libusb_device_handle *devh;
+ uint32_t xfer_num;
+ uint32_t xfer_buf_num;
+ uint32_t xfer_buf_len;
+ struct libusb_transfer **xfer;
+ unsigned char **xfer_buf;
+
+ fl2k_xfer_info_t *xfer_info;
+
+ fl2k_tx_cb_t cb;
+ void *cb_ctx;
+ enum fl2k_async_status async_status;
+ int async_cancel;
+
+ int use_zerocopy;
+ int terminate;
+
+ /* thread related */
+ pthread_t usb_worker_thread;
+ pthread_t sample_worker_thread;
+ pthread_mutex_t buf_mutex;
+ pthread_cond_t buf_cond;
+
+ double rate; /* Hz */
+
+ /* status */
+ int dev_lost;
+ int driver_active;
+ uint32_t underflow_cnt;
+};
+
+typedef struct fl2k_dongle {
+ uint16_t vid;
+ uint16_t pid;
+ const char *name;
+} fl2k_dongle_t;
+
+static fl2k_dongle_t known_devices[] = {
+ { 0x1d5c, 0x2000, "FL2000DX OEM" },
+};
+
+#define DEFAULT_BUF_NUMBER 4
+
+#define CTRL_IN (LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_ENDPOINT_IN)
+#define CTRL_OUT (LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_ENDPOINT_OUT)
+#define CTRL_TIMEOUT 300
+#define BULK_TIMEOUT 0
+
+static int fl2k_read_reg(fl2k_dev_t *dev, uint16_t reg, uint32_t *val)
+{
+ int r;
+ uint8_t data[4];
+
+ if (!dev || !val)
+ return FL2K_ERROR_INVALID_PARAM;
+
+ r = libusb_control_transfer(dev->devh, CTRL_IN, 0x40,
+ 0, reg, data, 4, CTRL_TIMEOUT);
+
+ if (r < 4)
+ fprintf(stderr, "Error, short read from register!\n");
+
+ *val = (data[3] << 24) | (data[2] << 16) | (data[1] << 8) | data[0];
+
+ return r;
+}
+
+static int fl2k_write_reg(fl2k_dev_t *dev, uint16_t reg, uint32_t val)
+{
+ uint8_t data[4];
+
+ if (!dev)
+ return FL2K_ERROR_INVALID_PARAM;
+
+ data[0] = val & 0xff;
+ data[1] = (val >> 8) & 0xff;
+ data[2] = (val >> 16) & 0xff;
+ data[3] = (val >> 24) & 0xff;
+
+ return libusb_control_transfer(dev->devh, CTRL_OUT, 0x41,
+ 0, reg, data, 4, CTRL_TIMEOUT);
+}
+
+int fl2k_init_device(fl2k_dev_t *dev)
+{
+ if (!dev)
+ return FL2K_ERROR_INVALID_PARAM;
+
+ /* initialization */
+ fl2k_write_reg(dev, 0x8020, 0xdf0000cc);
+
+ /* set DAC freq to lowest value possible to avoid
+ * underrun during init */
+ fl2k_write_reg(dev, 0x802c, 0x00416f3f);
+
+ fl2k_write_reg(dev, 0x8048, 0x7ffb8004);
+ fl2k_write_reg(dev, 0x803c, 0xd701004d);
+ fl2k_write_reg(dev, 0x8004, 0x0000031c);
+ fl2k_write_reg(dev, 0x8004, 0x0010039d);
+ fl2k_write_reg(dev, 0x8008, 0x07800898);
+
+ fl2k_write_reg(dev, 0x801c, 0x00000000);
+ fl2k_write_reg(dev, 0x0070, 0x04186085);
+
+ /* blanking magic */
+ fl2k_write_reg(dev, 0x8008, 0xfeff0780);
+ fl2k_write_reg(dev, 0x800c, 0x0000f001);
+
+ /* VSYNC magic */
+ fl2k_write_reg(dev, 0x8010, 0x0400042a);
+ fl2k_write_reg(dev, 0x8014, 0x0010002d);
+
+ fl2k_write_reg(dev, 0x8004, 0x00000002);
+
+ return 0;
+}
+
+int fl2k_deinit_device(fl2k_dev_t *dev)
+{
+ int r = 0;
+
+ if (!dev)
+ return FL2K_ERROR_INVALID_PARAM;
+
+ /* TODO, power down DACs, PLL, put device in reset */
+
+ return r;
+}
+
+static double fl2k_reg_to_freq(uint32_t reg)
+{
+ double sample_clock, offset, offs_div;
+ uint32_t pll_clock = 160000000;
+ uint8_t div = reg & 0x3f;
+ uint8_t out_div = (reg >> 8) & 0xf;
+ uint8_t frac = (reg >> 16) & 0xf;
+ uint8_t mult = (reg >> 20) & 0xf;
+
+ sample_clock = (pll_clock * mult) / (uint32_t)div;
+ offs_div = (pll_clock / 5.0f ) * mult;
+ offset = ((double)sample_clock/(offs_div/2)) * 1000000.0f;
+ sample_clock += (uint32_t)offset * frac;
+ sample_clock /= out_div;
+
+// fprintf(stderr, "div: %d\tod: %d\tfrac: %d\tmult %d\tclock: %f\treg "
+// "%08x\n", div, out_div, frac, mult, sample_clock, reg);
+
+ return sample_clock;
+}
+
+int fl2k_set_sample_rate(fl2k_dev_t *dev, uint32_t target_freq)
+{
+ double sample_clock, error, last_error = 1e20f;
+ uint32_t reg = 0, result_reg = 0;
+ uint8_t div, mult, frac, out_div;
+
+ if (!dev)
+ return FL2K_ERROR_INVALID_PARAM;
+
+ /* Output divider (accepts value 1-15)
+ * works, but adds lots of phase noise, so do not use it */
+ out_div = 1;
+
+ /* Observation: PLL multiplier of 7 works, but has more phase
+ * noise. Prefer multiplier 6 and 5 */
+ for (mult = 6; mult >= 3; mult--) {
+ for (div = 63; div > 1; div--) {
+ for (frac = 1; frac <= 15; frac++) {
+ reg = (mult << 20) | (frac << 16) |
+ (0x60 << 8) | (out_div << 8) | div;
+
+ sample_clock = fl2k_reg_to_freq(reg);
+ error = sample_clock - (double)target_freq;
+
+ /* Keep closest match */
+ if (fabs(error) < last_error) {
+ result_reg = reg;
+ last_error = fabs(error);
+ }
+ }
+ }
+ }
+
+ sample_clock = fl2k_reg_to_freq(result_reg);
+ error = sample_clock - (double)target_freq;
+ dev->rate = sample_clock;
+
+ if (fabs(error) > 1)
+ fprintf(stderr, "Requested sample rate %d not possible, using"
+ " %f, error is %f\n", target_freq, sample_clock, error);
+
+ return fl2k_write_reg(dev, 0x802c, result_reg);
+}
+
+uint32_t fl2k_get_sample_rate(fl2k_dev_t *dev)
+{
+ if (!dev)
+ return 0;
+
+ return (uint32_t)dev->rate;
+}
+
+static fl2k_dongle_t *find_known_device(uint16_t vid, uint16_t pid)
+{
+ unsigned int i;
+ fl2k_dongle_t *device = NULL;
+
+ for (i = 0; i < sizeof(known_devices)/sizeof(fl2k_dongle_t); i++ ) {
+ if (known_devices[i].vid == vid && known_devices[i].pid == pid) {
+ device = &known_devices[i];
+ break;
+ }
+ }
+
+ return device;
+}
+
+uint32_t fl2k_get_device_count(void)
+{
+ int i,r;
+ libusb_context *ctx;
+ libusb_device **list;
+ uint32_t device_count = 0;
+ struct libusb_device_descriptor dd;
+ ssize_t cnt;
+
+ r = libusb_init(&ctx);
+ if (r < 0)
+ return 0;
+
+ cnt = libusb_get_device_list(ctx, &list);
+
+ for (i = 0; i < cnt; i++) {
+ libusb_get_device_descriptor(list[i], &dd);
+
+ if (find_known_device(dd.idVendor, dd.idProduct))
+ device_count++;
+ }
+
+ libusb_free_device_list(list, 1);
+
+ libusb_exit(ctx);
+
+ return device_count;
+}
+
+const char *fl2k_get_device_name(uint32_t index)
+{
+ int i,r;
+ libusb_context *ctx;
+ libusb_device **list;
+ struct libusb_device_descriptor dd;
+ fl2k_dongle_t *device = NULL;
+ uint32_t device_count = 0;
+ ssize_t cnt;
+
+ r = libusb_init(&ctx);
+ if (r < 0)
+ return "";
+
+ cnt = libusb_get_device_list(ctx, &list);
+
+ for (i = 0; i < cnt; i++) {
+ libusb_get_device_descriptor(list[i], &dd);
+
+ device = find_known_device(dd.idVendor, dd.idProduct);
+
+ if (device) {
+ device_count++;
+
+ if (index == device_count - 1)
+ break;
+ }
+ }
+
+ libusb_free_device_list(list, 1);
+
+ libusb_exit(ctx);
+
+ if (device)
+ return device->name;
+ else
+ return "";
+}
+
+int fl2k_open(fl2k_dev_t **out_dev, uint32_t index)
+{
+ int r;
+ int i;
+ libusb_device **list;
+ fl2k_dev_t *dev = NULL;
+ libusb_device *device = NULL;
+ uint32_t device_count = 0;
+ struct libusb_device_descriptor dd;
+ uint8_t reg;
+ ssize_t cnt;
+
+ dev = malloc(sizeof(fl2k_dev_t));
+ if (NULL == dev)
+ return -ENOMEM;
+
+ memset(dev, 0, sizeof(fl2k_dev_t));
+
+ r = libusb_init(&dev->ctx);
+ if(r < 0){
+ free(dev);
+ return -1;
+ }
+
+#if LIBUSB_API_VERSION >= 0x01000106
+ libusb_set_option(dev->ctx, LIBUSB_OPTION_LOG_LEVEL, 3);
+#else
+ libusb_set_debug(dev->ctx, 3);
+#endif
+
+ dev->dev_lost = 1;
+
+ cnt = libusb_get_device_list(dev->ctx, &list);
+
+ for (i = 0; i < cnt; i++) {
+ device = list[i];
+
+ libusb_get_device_descriptor(list[i], &dd);
+
+ if (find_known_device(dd.idVendor, dd.idProduct)) {
+ device_count++;
+ }
+
+ if (index == device_count - 1)
+ break;
+
+ device = NULL;
+ }
+
+ if (!device) {
+ r = -1;
+ goto err;
+ }
+
+ r = libusb_open(device, &dev->devh);
+ libusb_free_device_list(list, 1);
+ if (r < 0) {
+ fprintf(stderr, "usb_open error %d\n", r);
+ if(r == LIBUSB_ERROR_ACCESS)
+ fprintf(stderr, "Please fix the device permissions, e.g. "
+ "by installing the udev rules file\n");
+ goto err;
+ }
+
+ /* If the adapter has an SPI flash for the Windows driver, we
+ * need to detach the USB mass storage driver first in order to
+ * open the device */
+ if (libusb_kernel_driver_active(dev->devh, 3) == 1) {
+ fprintf(stderr, "Kernel mass storage driver is attached, "
+ "detaching driver. This may take more than"
+ " 10 seconds!\n");
+ r = libusb_detach_kernel_driver(dev->devh, 3);
+ if (r < 0) {
+ fprintf(stderr, "Failed to detach mass storage "
+ "driver: %d\n", r);
+ goto err;
+ }
+ }
+
+ r = libusb_claim_interface(dev->devh, 0);
+ if (r < 0) {
+ fprintf(stderr, "usb_claim_interface 0 error %d\n", r);
+ goto err;
+ }
+
+ r = libusb_set_interface_alt_setting(dev->devh, 0, 1);
+ if (r < 0) {
+ fprintf(stderr, "Failed to switch interface 0 to "
+ "altsetting 1, trying to use interface 1\n");
+
+ r = libusb_claim_interface(dev->devh, 1);
+ if (r < 0) {
+ fprintf(stderr, "Could not claim interface 1: %d\n", r);
+ }
+ }
+
+ r = fl2k_init_device(dev);
+ if (r < 0)
+ goto err;
+
+ dev->dev_lost = 0;
+
+found:
+ *out_dev = dev;
+
+ return 0;
+err:
+ if (dev) {
+ if (dev->ctx)
+ libusb_exit(dev->ctx);
+
+ free(dev);
+ }
+
+ return r;
+}
+
+int fl2k_close(fl2k_dev_t *dev)
+{
+ if (!dev)
+ return FL2K_ERROR_INVALID_PARAM;
+
+ if(!dev->dev_lost) {
+ /* block until all async operations have been completed (if any) */
+ while (FL2K_INACTIVE != dev->async_status)
+ sleep_ms(100);
+
+ fl2k_deinit_device(dev);
+ }
+
+ libusb_release_interface(dev->devh, 0);
+ libusb_close(dev->devh);
+ libusb_exit(dev->ctx);
+
+ free(dev);
+
+ return 0;
+}
+
+static struct libusb_transfer *fl2k_get_next_xfer(fl2k_dev_t *dev,
+ fl2k_buf_state_t state)
+{
+ unsigned int i;
+ int next_buf = -1;
+ uint64_t next_seq = 0;
+ fl2k_xfer_info_t *xfer_info;
+
+ for (i = 0; i < dev->xfer_buf_num; i++) {
+ xfer_info = (fl2k_xfer_info_t *)dev->xfer[i]->user_data;
+ if (!xfer_info)
+ continue;
+
+ if (xfer_info->state == state) {
+ if (state == BUF_EMPTY) {
+ return dev->xfer[i];
+ } else if ((xfer_info->seq < next_seq) || next_buf < 0) {
+ next_seq = xfer_info->seq;
+ next_buf = i;
+ }
+ }
+ }
+
+ if ((state == BUF_FILLED) && (next_buf >= 0))
+ return dev->xfer[next_buf];
+ else
+ return NULL;
+}
+
+static void LIBUSB_CALL _libusb_callback(struct libusb_transfer *xfer)
+{
+ fl2k_xfer_info_t *xfer_info = (fl2k_xfer_info_t *)xfer->user_data;
+ fl2k_xfer_info_t *next_xfer_info;
+ fl2k_dev_t *dev = (fl2k_dev_t *)xfer_info->dev;
+ struct libusb_transfer *next_xfer = NULL;
+ int r = 0;
+
+ if (LIBUSB_TRANSFER_COMPLETED == xfer->status) {
+ /* resubmit transfer */
+ if (FL2K_RUNNING == dev->async_status) {
+ /* get next transfer */
+ next_xfer = fl2k_get_next_xfer(dev, BUF_FILLED);
+
+ if (next_xfer) {
+ next_xfer_info = (fl2k_xfer_info_t *) next_xfer->user_data;
+
+ /* Submit next filled transfer */
+ next_xfer_info->state = BUF_SUBMITTED;
+ r = libusb_submit_transfer(next_xfer);
+ xfer_info->state = BUF_EMPTY;
+ pthread_cond_signal(&dev->buf_cond);
+ } else {
+ /* We need to re-submit the transfer
+ * in any case, as otherwise the device
+ * stops to output data and hangs
+ * (happens only in the hacked 'gapless'
+ * mode without HSYNC and VSYNC) */
+ r = libusb_submit_transfer(xfer);
+ pthread_cond_signal(&dev->buf_cond);
+ dev->underflow_cnt++;
+ }
+ }
+ }
+
+ if (((LIBUSB_TRANSFER_CANCELLED != xfer->status) &&
+ (LIBUSB_TRANSFER_COMPLETED != xfer->status)) ||
+ (r == LIBUSB_ERROR_NO_DEVICE)) {
+ dev->dev_lost = 1;
+ fl2k_stop_tx(dev);
+ pthread_cond_signal(&dev->buf_cond);
+ fprintf(stderr, "cb transfer status: %d, submit "
+ "transfer %d, canceling...\n", xfer->status, r);
+ }
+}
+
+static int fl2k_alloc_submit_transfers(fl2k_dev_t *dev)
+{
+ unsigned int i;
+ int r = 0;
+ const char *incr_usbfs = "Please increase your allowed usbfs buffer"
+ " size with the following command:\n"
+ "echo 0 > /sys/module/usbcore/parameters/"
+ "usbfs_memory_mb\n";
+
+ if (!dev)
+ return FL2K_ERROR_INVALID_PARAM;
+
+ dev->xfer = malloc(dev->xfer_buf_num * sizeof(struct libusb_transfer *));
+
+ for (i = 0; i < dev->xfer_buf_num; ++i)
+ dev->xfer[i] = libusb_alloc_transfer(0);
+
+ dev->xfer_buf = malloc(dev->xfer_buf_num * sizeof(unsigned char *));
+ memset(dev->xfer_buf, 0, dev->xfer_buf_num * sizeof(unsigned char *));
+
+ dev->xfer_info = malloc(dev->xfer_buf_num * sizeof(fl2k_xfer_info_t));
+ memset(dev->xfer_info, 0, dev->xfer_buf_num * sizeof(fl2k_xfer_info_t));
+
+#if defined (__linux__) && LIBUSB_API_VERSION >= 0x01000105
+ fprintf(stderr, "Allocating %d zero-copy buffers\n", dev->xfer_buf_num);
+
+ dev->use_zerocopy = 1;
+ for (i = 0; i < dev->xfer_buf_num; ++i) {
+ dev->xfer_buf[i] = libusb_dev_mem_alloc(dev->devh, dev->xfer_buf_len);
+
+ if (dev->xfer_buf[i]) {
+ /* Check if Kernel usbfs mmap() bug is present: if the
+ * mapping is correct, the buffers point to memory that
+ * was memset to 0 by the Kernel, otherwise, they point
+ * to random memory. We check if the buffers are zeroed
+ * and otherwise fall back to buffers in userspace.
+ */
+ if (dev->xfer_buf[i][0] || memcmp(dev->xfer_buf[i],
+ dev->xfer_buf[i] + 1,
+ dev->xfer_buf_len - 1)) {
+ fprintf(stderr, "Detected Kernel usbfs mmap() "
+ "bug, falling back to buffers "
+ "in userspace\n");
+ dev->use_zerocopy = 0;
+ break;
+ }
+ } else {
+ fprintf(stderr, "Failed to allocate zero-copy "
+ "buffer for transfer %d\n%sFalling "
+ "back to buffers in userspace\n",
+ i, incr_usbfs);
+ dev->use_zerocopy = 0;
+ break;
+ }
+ }
+
+ /* zero-copy buffer allocation failed (partially or completely)
+ * we need to free the buffers again if already allocated */
+ if (!dev->use_zerocopy) {
+ for (i = 0; i < dev->xfer_buf_num; ++i) {
+ if (dev->xfer_buf[i])
+ libusb_dev_mem_free(dev->devh,
+ dev->xfer_buf[i],
+ dev->xfer_buf_len);
+ }
+ }
+#endif
+
+ /* no zero-copy available, allocate buffers in userspace */
+ if (!dev->use_zerocopy) {
+ for (i = 0; i < dev->xfer_buf_num; ++i) {
+ dev->xfer_buf[i] = malloc(dev->xfer_buf_len);
+
+ if (!dev->xfer_buf[i])
+ return FL2K_ERROR_NO_MEM;
+ }
+ }
+
+ /* fill transfers */
+ for (i = 0; i < dev->xfer_buf_num; ++i) {
+ libusb_fill_bulk_transfer(dev->xfer[i],
+ dev->devh,
+ 0x01,
+ dev->xfer_buf[i],
+ dev->xfer_buf_len,
+ _libusb_callback,
+ &dev->xfer_info[i],
+ 0);
+
+ dev->xfer_info[i].dev = dev;
+ dev->xfer_info[i].state = BUF_EMPTY;
+
+ /* if we allocate the memory through the Kernel, it is
+ * already cleared */
+ if (!dev->use_zerocopy)
+ memset(dev->xfer_buf[i], 0, dev->xfer_buf_len);
+ }
+
+ /* submit transfers */
+ for (i = 0; i < dev->xfer_num; ++i) {
+ r = libusb_submit_transfer(dev->xfer[i]);
+ dev->xfer_info[i].state = BUF_SUBMITTED;
+
+ if (r < 0) {
+ fprintf(stderr, "Failed to submit transfer %i\n%s",
+ i, incr_usbfs);
+ break;
+ }
+ }
+
+ return 0;
+}
+
+static int _fl2k_free_async_buffers(fl2k_dev_t *dev)
+{
+ unsigned int i;
+
+ if (!dev)
+ return FL2K_ERROR_INVALID_PARAM;
+
+ if (dev->xfer) {
+ for (i = 0; i < dev->xfer_buf_num; ++i) {
+ if (dev->xfer[i]) {
+ libusb_free_transfer(dev->xfer[i]);
+ }
+ }
+
+ free(dev->xfer);
+ dev->xfer = NULL;
+ }
+
+ if (dev->xfer_buf) {
+ for (i = 0; i < dev->xfer_buf_num; ++i) {
+ if (dev->xfer_buf[i]) {
+ if (dev->use_zerocopy) {
+#if defined (__linux__) && LIBUSB_API_VERSION >= 0x01000105
+ libusb_dev_mem_free(dev->devh,
+ dev->xfer_buf[i],
+ dev->xfer_buf_len);
+#endif
+ } else {
+ free(dev->xfer_buf[i]);
+ }
+ }
+ }
+
+ free(dev->xfer_buf);
+ dev->xfer_buf = NULL;
+ }
+
+ return 0;
+}
+
+static void *fl2k_usb_worker(void *arg)
+{
+ fl2k_dev_t *dev = (fl2k_dev_t *)arg;
+ struct timeval tv = { 1, 0 };
+ struct timeval zerotv = { 0, 0 };
+ enum fl2k_async_status next_status = FL2K_INACTIVE;
+ int r = 0;
+ unsigned int i;
+
+ while (FL2K_RUNNING == dev->async_status) {
+ r = libusb_handle_events_timeout_completed(dev->ctx, &tv,
+ &dev->async_cancel);
+ }
+
+ while (FL2K_INACTIVE != dev->async_status) {
+ r = libusb_handle_events_timeout_completed(dev->ctx, &tv,
+ &dev->async_cancel);
+ if (r < 0) {
+ /*fprintf(stderr, "handle_events returned: %d\n", r);*/
+ if (r == LIBUSB_ERROR_INTERRUPTED) /* stray signal */
+ continue;
+ break;
+ }
+
+ if (FL2K_CANCELING == dev->async_status) {
+ next_status = FL2K_INACTIVE;
+
+ if (!dev->xfer)
+ break;
+
+ for (i = 0; i < dev->xfer_buf_num; ++i) {
+ if (!dev->xfer[i])
+ continue;
+
+ if (LIBUSB_TRANSFER_CANCELLED !=
+ dev->xfer[i]->status) {
+ r = libusb_cancel_transfer(dev->xfer[i]);
+ /* handle events after canceling
+ * to allow transfer status to
+ * propagate */
+ libusb_handle_events_timeout_completed(dev->ctx,
+ &zerotv, NULL);
+ if (r < 0)
+ continue;
+
+ next_status = FL2K_CANCELING;
+ }
+ }
+
+ if (dev->dev_lost || FL2K_INACTIVE == next_status) {
+ /* handle any events that still need to
+ * be handled before exiting after we
+ * just cancelled all transfers */
+ libusb_handle_events_timeout_completed(dev->ctx,
+ &zerotv, NULL);
+ break;
+ }
+ }
+ }
+
+ /* wake up sample worker */
+ pthread_cond_signal(&dev->buf_cond);
+
+ /* wait for sample worker thread to finish before freeing buffers */
+ pthread_join(dev->sample_worker_thread, NULL);
+ _fl2k_free_async_buffers(dev);
+ dev->async_status = next_status;
+
+ pthread_exit(NULL);
+}
+
+/* Buffer format conversion functions for R, G, B DACs */
+static inline void fl2k_convert_r(char *out,
+ char *in,
+ uint32_t len,
+ uint8_t offset)
+{
+ unsigned int i, j = 0;
+
+ if (!in || !out)
+ return;
+
+ for (i = 0; i < len; i += 24) {
+ out[i+ 6] = in[j++] + offset;
+ out[i+ 1] = in[j++] + offset;
+ out[i+12] = in[j++] + offset;
+ out[i+15] = in[j++] + offset;
+ out[i+10] = in[j++] + offset;
+ out[i+21] = in[j++] + offset;
+ out[i+16] = in[j++] + offset;
+ out[i+19] = in[j++] + offset;
+ }
+}
+
+static inline void fl2k_convert_g(char *out,
+ char *in,
+ uint32_t len,
+ uint8_t offset)
+{
+ unsigned int i, j = 0;
+
+ if (!in || !out)
+ return;
+
+ for (i = 0; i < len; i += 24) {
+ out[i+ 5] = in[j++] + offset;
+ out[i+ 0] = in[j++] + offset;
+ out[i+ 3] = in[j++] + offset;
+ out[i+14] = in[j++] + offset;
+ out[i+ 9] = in[j++] + offset;
+ out[i+20] = in[j++] + offset;
+ out[i+23] = in[j++] + offset;
+ out[i+18] = in[j++] + offset;
+ }
+}
+
+static inline void fl2k_convert_b(char *out,
+ char *in,
+ uint32_t len,
+ uint8_t offset)
+{
+ unsigned int i, j = 0;
+
+ if (!in || !out)
+ return;
+
+ for (i = 0; i < len; i += 24) {
+ out[i+ 4] = in[j++] + offset;
+ out[i+ 7] = in[j++] + offset;
+ out[i+ 2] = in[j++] + offset;
+ out[i+13] = in[j++] + offset;
+ out[i+ 8] = in[j++] + offset;
+ out[i+11] = in[j++] + offset;
+ out[i+22] = in[j++] + offset;
+ out[i+17] = in[j++] + offset;
+ }
+}
+
+static void *fl2k_sample_worker(void *arg)
+{
+ int r = 0;
+ unsigned int i, j;
+ fl2k_dev_t *dev = (fl2k_dev_t *)arg;
+ fl2k_xfer_info_t *xfer_info = NULL;
+ struct libusb_transfer *xfer = NULL;
+ char *out_buf = NULL;
+ fl2k_data_info_t data_info;
+ uint32_t underflows = 0;
+ uint64_t buf_cnt = 0;
+
+ while (FL2K_RUNNING == dev->async_status) {
+ memset(&data_info, 0, sizeof(fl2k_data_info_t));
+
+ data_info.len = FL2K_BUF_LEN;
+ data_info.underflow_cnt = dev->underflow_cnt;
+ data_info.ctx = dev->cb_ctx;
+
+ if (dev->underflow_cnt > underflows) {
+ fprintf(stderr, "Underflow! Skipped %d buffers\n",
+ dev->underflow_cnt - underflows);
+ underflows = dev->underflow_cnt;
+ }
+
+ /* call application callback to get samples */
+ if (dev->cb)
+ dev->cb(&data_info);
+
+ xfer = fl2k_get_next_xfer(dev, BUF_EMPTY);
+
+ if (!xfer) {
+ pthread_cond_wait(&dev->buf_cond, &dev->buf_mutex);
+ /* in the meantime, the device might be gone */
+ if (FL2K_RUNNING != dev->async_status)
+ break;
+
+ xfer = fl2k_get_next_xfer(dev, BUF_EMPTY);
+ if (!xfer) {
+ fprintf(stderr, "no free transfer, skipping"
+ " input buffer\n");
+ continue;
+ }
+ }
+
+ /* We have an empty USB transfer buffer */
+ xfer_info = (fl2k_xfer_info_t *)xfer->user_data;
+ out_buf = (char *)xfer->buffer;
+
+ /* Re-arrange and copy bytes in buffer for DACs */
+ fl2k_convert_r(out_buf, data_info.r_buf, dev->xfer_buf_len,
+ data_info.sampletype_signed ? 128 : 0);
+
+ fl2k_convert_g(out_buf, data_info.g_buf, dev->xfer_buf_len,
+ data_info.sampletype_signed ? 128 : 0);
+
+ fl2k_convert_b(out_buf, data_info.b_buf, dev->xfer_buf_len,
+ data_info.sampletype_signed ? 128 : 0);
+
+ xfer_info->seq = buf_cnt++;
+ xfer_info->state = BUF_FILLED;
+ }
+
+ /* notify application if we've lost the device */
+ if (dev->dev_lost && dev->cb) {
+ data_info.device_error = 1;
+ dev->cb(&data_info);
+ }
+
+ pthread_exit(NULL);
+}
+
+
+int fl2k_start_tx(fl2k_dev_t *dev, fl2k_tx_cb_t cb, void *ctx,
+ uint32_t buf_num)
+{
+ int r = 0;
+ int i;
+ pthread_attr_t attr;
+
+ if (!dev || !cb)
+ return FL2K_ERROR_INVALID_PARAM;
+
+ dev->async_status = FL2K_RUNNING;
+ dev->async_cancel = 0;
+
+ dev->cb = cb;
+ dev->cb_ctx = ctx;
+
+ if (buf_num > 0)
+ dev->xfer_num = buf_num;
+ else
+ dev->xfer_num = DEFAULT_BUF_NUMBER;
+
+ /* have two spare buffers that can be filled while the
+ * others are submitted */
+ dev->xfer_buf_num = dev->xfer_num + 2;
+ dev->xfer_buf_len = FL2K_XFER_LEN;
+
+ r = fl2k_alloc_submit_transfers(dev);
+ if (r < 0)
+ goto cleanup;
+
+ pthread_mutex_init(&dev->buf_mutex, NULL);
+ pthread_cond_init(&dev->buf_cond, NULL);
+ pthread_attr_init(&attr);
+
+ r = pthread_create(&dev->usb_worker_thread, &attr,
+ fl2k_usb_worker, (void *)dev);
+ if (r < 0) {
+ fprintf(stderr, "Error spawning USB worker thread!\n");
+ goto cleanup;
+ }
+
+ r = pthread_create(&dev->sample_worker_thread, &attr,
+ fl2k_sample_worker, (void *)dev);
+ if (r < 0) {
+ fprintf(stderr, "Error spawning sample worker thread!\n");
+ goto cleanup;
+ }
+
+ pthread_attr_destroy(&attr);
+
+ return 0;
+
+cleanup:
+ _fl2k_free_async_buffers(dev);
+ return FL2K_ERROR_BUSY;
+
+}
+
+int fl2k_stop_tx(fl2k_dev_t *dev)
+{
+ if (!dev)
+ return FL2K_ERROR_INVALID_PARAM;
+
+ /* if streaming, try to cancel gracefully */
+ if (FL2K_RUNNING == dev->async_status) {
+ dev->async_status = FL2K_CANCELING;
+ dev->async_cancel = 1;
+ return 0;
+ /* if called while in pending state, change the state forcefully */
+ } else if (FL2K_INACTIVE != dev->async_status) {
+ dev->async_status = FL2K_INACTIVE;
+ return 0;
+ }
+
+ return FL2K_ERROR_BUSY;
+}
+
+int fl2k_i2c_read(fl2k_dev_t *dev, uint8_t i2c_addr, uint8_t reg_addr, uint8_t *data)
+{
+ int i, r, timeout = 1;
+ uint32_t reg;
+
+ if (!dev)
+ return FL2K_ERROR_INVALID_PARAM;
+
+ r = fl2k_read_reg(dev, 0x8020, &reg);
+ if (r < 0)
+ return r;
+
+ /* apply mask, clearing bit 30 disables periodic repetition of read */
+ reg &= 0x3ffc0000;
+
+ /* set I2C register and address, select I2C read (bit 7) */
+ reg |= (1 << 28) | (reg_addr << 8) | (1 << 7) | (i2c_addr & 0x7f);
+
+ r = fl2k_write_reg(dev, 0x8020, reg);
+ if (r < 0)
+ return r;
+
+ for (i = 0; i < 10; i++) {
+ sleep_ms(10);
+
+ r = fl2k_read_reg(dev, 0x8020, &reg);
+ if (r < 0)
+ return r;
+
+ /* check if operation completed */
+ if (reg & (1 << 31)) {
+ timeout = 0;
+ break;
+ }
+ }
+
+ if (timeout)
+ return FL2K_ERROR_TIMEOUT;
+
+ /* check if slave responded and all data was read */
+ if (reg & (0x0f << 24))
+ return FL2K_ERROR_NOT_FOUND;
+
+ /* read data from register 0x8024 */
+ return libusb_control_transfer(dev->devh, CTRL_IN, 0x40,
+ 0, 0x8024, data, 4, CTRL_TIMEOUT);
+}
+
+int fl2k_i2c_write(fl2k_dev_t *dev, uint8_t i2c_addr, uint8_t reg_addr, uint8_t *data)
+{
+ int i, r, timeout = 1;
+ uint32_t reg;
+
+ if (!dev)
+ return FL2K_ERROR_INVALID_PARAM;
+
+ /* write data to register 0x8028 */
+ r = libusb_control_transfer(dev->devh, CTRL_OUT, 0x41,
+ 0, 0x8028, data, 4, CTRL_TIMEOUT);
+
+ if (r < 0)
+ return r;
+
+ r = fl2k_read_reg(dev, 0x8020, &reg);
+ if (r < 0)
+ return r;
+
+ /* apply mask, clearing bit 30 disables periodic repetition of read */
+ reg &= 0x3ffc0000;
+
+ /* set I2C register and address */
+ reg |= (1 << 28) | (reg_addr << 8) | (i2c_addr & 0x7f);
+
+ r = fl2k_write_reg(dev, 0x8020, reg);
+ if (r < 0)
+ return r;
+
+ for (i = 0; i < 10; i++) {
+ sleep_ms(10);
+
+ r = fl2k_read_reg(dev, 0x8020, &reg);
+ if (r < 0)
+ return r;
+
+ /* check if operation completed */
+ if (reg & (1 << 31)) {
+ timeout = 0;
+ break;
+ }
+ }
+
+ if (timeout)
+ return FL2K_ERROR_TIMEOUT;
+
+ /* check if slave responded and all data was written */
+ if (reg & (0x0f << 24))
+ return FL2K_ERROR_NOT_FOUND;
+
+ return FL2K_SUCCESS;
+}
diff --git a/c_sources/osmo-fl2k.h b/c_sources/osmo-fl2k.h
new file mode 100644
index 0000000..14f2e2a
--- /dev/null
+++ b/c_sources/osmo-fl2k.h
@@ -0,0 +1,163 @@
+/*
+ * osmo-fl2k, turns FL2000-based USB 3.0 to VGA adapters into
+ * low cost DACs
+ *
+ * Copyright (C) 2016-2018 by Steve Markgraf <steve@steve-m.de>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __FL2K_H
+#define __FL2K_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stdint.h>
+#include "osmo-fl2k_export.h"
+
+enum fl2k_error {
+ FL2K_SUCCESS = 0,
+ FL2K_TRUE = 1,
+ FL2K_ERROR_INVALID_PARAM = -1,
+ FL2K_ERROR_NO_DEVICE = -2,
+ FL2K_ERROR_NOT_FOUND = -5,
+ FL2K_ERROR_BUSY = -6,
+ FL2K_ERROR_TIMEOUT = -7,
+ FL2K_ERROR_NO_MEM = -11,
+};
+
+typedef struct fl2k_data_info {
+ /* information provided by library */
+ void *ctx;
+ uint32_t underflow_cnt; /* underflows since last callback */
+ uint32_t len; /* buffer length */
+ int using_zerocopy; /* using zerocopy kernel buffers */
+ int device_error; /* device error happened, terminate application */
+
+ /* filled in by application */
+ int sampletype_signed; /* are samples signed or unsigned? */
+ char *r_buf; /* pointer to red buffer */
+ char *g_buf; /* pointer to green buffer */
+ char *b_buf; /* pointer to blue buffer */
+} fl2k_data_info_t;
+
+typedef struct fl2k_dev fl2k_dev_t;
+
+/** The transfer length was chosen by the following criteria:
+ * - Must be a supported resolution of the FL2000DX
+ * - Must be a multiple of 61440 bytes (URB payload length),
+ * which is important for using the DAC without HSYNC/VSYNC blanking,
+ * otherwise a couple of samples are missing between every buffer
+ * - Should be smaller than 4MB in order to be allocatable by kmalloc()
+ * for zerocopy transfers
+ **/
+#define FL2K_BUF_LEN (1280 * 1024)
+#define FL2K_XFER_LEN (FL2K_BUF_LEN * 3)
+
+FL2K_API uint32_t fl2k_get_device_count(void);
+
+FL2K_API const char* fl2k_get_device_name(uint32_t index);
+
+FL2K_API int fl2k_open(fl2k_dev_t **dev, uint32_t index);
+
+FL2K_API int fl2k_close(fl2k_dev_t *dev);
+
+/* configuration functions */
+
+/*!
+ * Set the sample rate (pixel clock) for the device
+ *
+ * \param dev the device handle given by fl2k_open()
+ * \param samp_rate the sample rate to be set, maximum value depends
+ * on host and USB controller
+ * \return 0 on success, -EINVAL on invalid rate
+ */
+FL2K_API int fl2k_set_sample_rate(fl2k_dev_t *dev, uint32_t target_freq);
+
+/*!
+ * Get actual sample rate the device is configured to.
+ *
+ * \param dev the device handle given by fl2k_open()
+ * \return 0 on error, sample rate in Hz otherwise
+ */
+FL2K_API uint32_t fl2k_get_sample_rate(fl2k_dev_t *dev);
+
+/* streaming functions */
+
+typedef void(*fl2k_tx_cb_t)(fl2k_data_info_t *data_info);
+
+/*!
+ * Starts the tx thread. This function will block until
+ * it is being canceled using fl2k_stop_tx()
+ *
+ * \param dev the device handle given by fl2k_open()
+ * \param ctx user specific context to pass via the callback function
+ * \param buf_num optional buffer count, buf_num * FL2K_BUF_LEN = overall buffer size
+ * set to 0 for default buffer count (4)
+ * \return 0 on success
+ */
+FL2K_API int fl2k_start_tx(fl2k_dev_t *dev, fl2k_tx_cb_t cb,
+ void *ctx, uint32_t buf_num);
+
+/*!
+ * Cancel all pending asynchronous operations on the device.
+ *
+ * \param dev the device handle given by fl2k_open()
+ * \return 0 on success
+ */
+FL2K_API int fl2k_stop_tx(fl2k_dev_t *dev);
+
+/*!
+ * Read 4 bytes via the FL2K I2C bus
+ *
+ * \param dev the device handle given by fl2k_open()
+ * \param i2c_addr address of the I2C device
+ * \param reg_addr start address of the 4 bytes to be read
+ * \param data pointer to byte array of size 4
+ * \return 0 on success
+ * \note A read operation will look like this on the bus:
+ * START, I2C_ADDR(W), REG_ADDR, REP_START, I2C_ADDR(R), DATA[0], STOP
+ * START, I2C_ADDR(W), REG_ADDR+1, REP_START, I2C_ADDR(R), DATA[1], STOP
+ * START, I2C_ADDR(W), REG_ADDR+2, REP_START, I2C_ADDR(R), DATA[2], STOP
+ * START, I2C_ADDR(W), REG_ADDR+3, REP_START, I2C_ADDR(R), DATA[3], STOP
+ */
+FL2K_API int fl2k_i2c_read(fl2k_dev_t *dev, uint8_t i2c_addr,
+ uint8_t reg_addr, uint8_t *data);
+
+/*!
+ * Write 4 bytes via the FL2K I2C bus
+ *
+ * \param dev the device handle given by fl2k_open()
+ * \param i2c_addr address of the I2C device
+ * \param reg_addr start address of the 4 bytes to be written
+ * \param data pointer to byte array of size 4
+ * \return 0 on success
+ * \note A write operation will look like this on the bus:
+ * START, I2C_ADDR(W), REG_ADDR, DATA[0], STOP
+ * START, I2C_ADDR(W), REG_ADDR+1, DATA[1], STOP
+ * START, I2C_ADDR(W), REG_ADDR+2, DATA[2], STOP
+ * START, I2C_ADDR(W), REG_ADDR+3, DATA[3], STOP
+ */
+FL2K_API int fl2k_i2c_write(fl2k_dev_t *dev, uint8_t i2c_addr,
+ uint8_t reg_addr, uint8_t *data);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __FL2K_H */
diff --git a/c_sources/osmo-fl2k_export.h b/c_sources/osmo-fl2k_export.h
new file mode 100644
index 0000000..71cba1a
--- /dev/null
+++ b/c_sources/osmo-fl2k_export.h
@@ -0,0 +1,51 @@
+/*
+ * osmo-fl2k, turns FL2000-based USB 3.0 to VGA adapters into
+ * low cost DACs
+ *
+ * Copyright (C) 2016-2018 by Steve Markgraf <steve@steve-m.de>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef FL2K_EXPORT_H
+#define FL2K_EXPORT_H
+
+#if defined __GNUC__
+# if __GNUC__ >= 4
+# define __FL2K_EXPORT __attribute__((visibility("default")))
+# define __FL2K_IMPORT __attribute__((visibility("default")))
+# else
+# define __FL2K_EXPORT
+# define __FL2K_IMPORT
+# endif
+#elif _MSC_VER
+# define __FL2K_EXPORT __declspec(dllexport)
+# define __FL2K_IMPORT __declspec(dllimport)
+#else
+# define __FL2K_EXPORT
+# define __FL2K_IMPORT
+#endif
+
+#ifndef libosmofl2k_STATIC
+# ifdef fl2k_EXPORTS
+# define FL2K_API __FL2K_EXPORT
+# else
+# define FL2K_API __FL2K_IMPORT
+# endif
+#else
+#define FL2K_API
+#endif
+#endif /* FL2K_EXPORT_H */