--- /dev/null
+#define LOCAL_DEBUG
+
+#include <ucw/lib.h>
+#include <ucw/bitops.h>
+#include <ucw/gary.h>
+#include <ucw/mainloop.h>
+#include <ucw/string.h>
+
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <sys/poll.h>
+
+#include <libusb.h>
+
+/*
+ * Interface to Novation Nocturn
+ *
+ * Protocol reverse-engineered by De Wet van Niekerk <dewert@gmail.com>,
+ * see https://github.com/dewert/nocturn-linux-midi for inspiration.
+ */
+
+static libusb_context *usb_ctx;
+static libusb_device_handle *usb_dev;
+
+static struct main_file **usb_fds;
+
+static int usb_fd_ready(struct main_file *f UNUSED)
+{
+ DBG("USB: Handling events (ready on fd %d)", f->fd);
+ struct timeval tv = { 0, 0 };
+ int comp = 0;
+ int err = libusb_handle_events_timeout_completed(usb_ctx, &tv, &comp);
+ if (err < 0)
+ msg(L_ERROR, "libusb_handle_events: error %d", err);
+ return HOOK_IDLE;
+}
+
+static void usb_added_fd(int fd, short events, void *user_data UNUSED)
+{
+ if (fd >= (int) GARY_SIZE(usb_fds))
+ GARY_RESIZE(usb_fds, fd + 1);
+
+ struct main_file *f = usb_fds[fd];
+ if (!f)
+ {
+ f = xmalloc_zero(sizeof(*f));
+ usb_fds[fd] = f;
+ }
+ else if (file_is_active(f))
+ {
+ DBG("USB: Releasing fd %d", fd);
+ file_del(f);
+ }
+
+ DBG("USB: Adding fd %d with event mask %u", fd, events);
+ f->fd = fd;
+ f->read_handler = (events & POLLIN) ? usb_fd_ready : NULL;
+ f->write_handler = (events & POLLOUT) ? usb_fd_ready : NULL;
+ file_add(f);
+}
+
+static void usb_removed_fd(int fd, void *user_data UNUSED)
+{
+ DBG("USB: Releasing fd %d", fd);
+ ASSERT(fd < (int) GARY_SIZE(usb_fds));
+ struct main_file *f = usb_fds[fd];
+ ASSERT(f);
+ ASSERT(file_is_active(f));
+ file_del(f);
+}
+
+static const char noct_init[4][9] = {
+ { 3, 0xb0, 0x00, 0x00 },
+ { 8, 0x28, 0x00, 0x2b, 0x4a, 0x2c, 0x00, 0x2e, 0x35 },
+ { 6, 0x2a, 0x02, 0x2c, 0x72, 0x2e, 0x30 },
+ { 2, 0x7f, 0x00 },
+};
+
+static void noct_read_done(struct libusb_transfer *xfer)
+{
+ byte *pkt = xfer->buffer;
+ int len = xfer->actual_length;
+ DBG("USB: Read done: status %d, length %d", xfer->status, len);
+
+ if (xfer->status != LIBUSB_TRANSFER_COMPLETED)
+ {
+ msg(L_ERROR, "USB read failed with status %d, not submitting again", xfer->status);
+ return;
+ }
+
+#ifdef LOCAL_DEBUG
+ char buf[256];
+ mem_to_hex(buf, pkt, len, ' ');
+ DBG("USB: Read <%s>", buf);
+#endif
+
+ int i = 0;
+ while (i < len)
+ {
+ if (i + 3 > len)
+ {
+ msg(L_ERROR, "Unknown USB packet: length %d not divisible by 3", len);
+ break;
+ }
+ if (pkt[i] != 0xb0)
+ {
+ msg(L_ERROR, "Unknown USB packet: expected 0xb0 at position %d", i);
+ break;
+ }
+ int cmd = pkt[i+1];
+ int arg = pkt[i+2];
+ i += 3;
+ switch (cmd)
+ {
+ case 0x30:
+ // Unknown packet sent during init
+ continue;
+ case 0x40 ... 0x47:
+ if (arg < 0x80)
+ {
+ int r = cmd - 0x40;
+ int delta = (arg < 0x40 ? arg : arg - 0x80);
+ DBG("Noct: Rotary %d = %d", r, delta);
+ continue;
+ }
+ break;
+ case 0x48:
+ if (arg < 0x80)
+ {
+ DBG("Noct: Slider value = %d", arg);
+ continue;
+ }
+ break;
+ case 0x49:
+ // Unknown packet, maybe least significant bit of slider
+ continue;
+ case 0x4a:
+ if (arg < 0x80)
+ {
+ int delta = (arg < 0x40 ? arg : arg - 0x80);
+ DBG("Noct: Center = %d", delta);
+ continue;
+ }
+ break;
+ case 0x52:
+ if (arg == 0x00 || arg == 0x7f)
+ {
+ int state = !!arg;
+ DBG("Noct: Center touch = %d", state);
+ continue;
+ }
+ break;
+ case 0x53:
+ if (arg == 0x00 || arg == 0x7f)
+ {
+ int state = !!arg;
+ DBG("Noct: Slider touch = %d", state);
+ continue;
+ }
+ break;
+ case 0x60 ... 0x67:
+ if (arg == 0x00 || arg == 0x7f)
+ {
+ int r = cmd - 0x60;
+ int state = !!arg;
+ DBG("Noct: Rotary %d touch = %d", r, state);
+ continue;
+ }
+ break;
+ case 0x70 ... 0x7f:
+ if (arg == 0x00 || arg == 0x7f)
+ {
+ int b = cmd - 0x70;
+ int state = !!arg;
+ DBG("Noct: Button %d = %d", b, state);
+ continue;
+ }
+ break;
+ }
+ msg(L_ERROR, "Unknown USB packet: unrecognized cmd=%02x arg=%02x", cmd, arg);
+ }
+
+ int err;
+ if ((err = libusb_submit_transfer(xfer)) < 0)
+ die("Cannot submit transfer: error %d", err);
+}
+
+static void noct_read_init(void)
+{
+ DBG("Noct: Read init");
+
+ struct libusb_transfer *xfer = libusb_alloc_transfer(0);
+ libusb_fill_interrupt_transfer(xfer, usb_dev, 0x81, xmalloc(8), 8, noct_read_done, NULL, 0);
+
+ int err;
+ if ((err = libusb_submit_transfer(xfer)) < 0)
+ die("Cannot submit transfer: error %d", err);
+}
+
+static byte noct_button_state[16];
+static byte noct_ring_mode[8]; // 0=from-min, 1=from-max, 2=from-mid-right, 3=from-mid-both, 4=single-on, 5=single-off
+static byte noct_ring_val[9];
+
+static uns noct_dirty_button;
+static uns noct_dirty_ring_mode;
+static uns noct_dirty_ring_val;
+
+static struct libusb_transfer *noct_write_xfer;
+static uns noct_write_pending;
+static void noct_sched_write(void);
+
+static void noct_write_done(struct libusb_transfer *xfer)
+{
+ int len = xfer->actual_length;
+ DBG("USB: Write done: status %d, length %d", xfer->status, len);
+
+ if (xfer->status != LIBUSB_TRANSFER_COMPLETED)
+ {
+ msg(L_ERROR, "USB write failed with status %d", xfer->status);
+ return;
+ }
+
+ noct_write_pending = 0;
+ noct_sched_write();
+}
+
+static void noct_do_write(uns cmd, uns arg)
+{
+ DBG("USB: Submitting write %02x %02x", cmd, arg);
+ ASSERT(!noct_write_pending);
+ noct_write_pending = 1;
+
+ struct libusb_transfer *xfer = noct_write_xfer;
+ byte *pkt = xfer->buffer;
+ pkt[0] = cmd;
+ pkt[1] = arg;
+ xfer->length = 2;
+
+ int err;
+ if ((err = libusb_submit_transfer(xfer)) < 0)
+ die("Cannot submit transfer: error %d", err);
+}
+
+static void noct_sched_write(void)
+{
+ if (noct_write_pending)
+ return;
+
+ if (noct_dirty_button)
+ {
+ int i = bit_fls(noct_dirty_button);
+ noct_dirty_button ^= 1U << i;
+ noct_do_write(0x70 + i, noct_button_state[i]);
+ }
+ else if (noct_dirty_ring_mode)
+ {
+ int i = bit_fls(noct_dirty_ring_mode);
+ noct_dirty_ring_mode ^= 1U << i;
+ noct_do_write(0x48 + i, noct_ring_mode[i] << 4);
+ }
+ else if (noct_dirty_ring_val)
+ {
+ int i = bit_fls(noct_dirty_ring_val);
+ noct_dirty_ring_val ^= 1U << i;
+ if (i == 8)
+ noct_do_write(0x50 + i, noct_ring_val[i]);
+ else
+ noct_do_write(0x40 + i, noct_ring_val[i]);
+ }
+}
+
+static void noct_write_init(void)
+{
+ DBG("Noct: Write init");
+
+ noct_write_xfer = libusb_alloc_transfer(0);
+ libusb_fill_interrupt_transfer(noct_write_xfer, usb_dev, 0x02, xmalloc(8), 0, noct_write_done, NULL, 1000);
+
+#if 0 // FIXME
+ noct_button_state[2] = 1;
+ noct_ring_mode[0] = 4;
+ noct_ring_val[0] = 0x40;
+#endif
+
+ noct_dirty_button = 0xffff;
+ noct_dirty_ring_mode = 0xff;
+ noct_dirty_ring_val = 0x1ff;
+ noct_sched_write();
+}
+
+static void usb_init(void)
+{
+ int err;
+
+ if ((err = libusb_init(&usb_ctx)) < 0)
+ die("libusb_init failed: error %d", err);
+ libusb_set_debug(usb_ctx, 3);
+
+ libusb_device **dev_list;
+ libusb_device *found_dev = NULL;
+ ssize_t len = libusb_get_device_list(usb_ctx, &dev_list);
+ for (ssize_t i=0; i < len; i++)
+ {
+ libusb_device *dev = dev_list[i];
+ struct libusb_device_descriptor desc;
+ if (libusb_get_device_descriptor(dev, &desc) >= 0 &&
+ desc.idVendor == 0x1235 &&
+ desc.idProduct == 0x000a)
+ {
+ msg(L_DEBUG, "Found device: bus %d, addr %d", libusb_get_bus_number(dev), libusb_get_device_address(dev));
+ if (found_dev)
+ die("Multiple Nocturn devices found. Please fix me to handle it.");
+ found_dev = libusb_ref_device(dev);
+ }
+ }
+ libusb_free_device_list(dev_list, 1);
+
+ if (!found_dev)
+ die("No Nocturn device found");
+
+ msg(L_DEBUG, "Initializing device");
+
+ if ((err = libusb_open(found_dev, &usb_dev)) < 0)
+ die("libusb_open failed: error %d", err);
+
+ // There exist configurations 1 (high brightness) and 2 (power-save)
+ if ((err = libusb_set_configuration(usb_dev, 1)) < 0)
+ die("libusb_set_configuration: error %d", err);
+
+ if ((err = libusb_claim_interface(usb_dev, 0)) < 0)
+ die("libusb_claim_interface: error %d", err);
+
+ for (int i=0; i<4; i++)
+ {
+ int done;
+ if ((err = libusb_interrupt_transfer(usb_dev, 0x02, (byte *) noct_init[i] + 1, noct_init[i][0], &done, 5000)) < 0)
+ die("Cannot send init packets: error %d", err);
+ if (done != noct_init[i][0])
+ die("Partial send of init packet: %d < %d", done, noct_init[i][0]);
+ }
+
+#if 0
+ byte xxx[] = { 0x7f, 0x01 };
+ int done;
+ libusb_interrupt_transfer(usb_dev, 0x02, xxx, 2, &done, 5000);
+#endif
+
+ DBG("USB: Connecting libusb to mainloop");
+
+ if (!libusb_pollfds_handle_timeouts(usb_ctx))
+ die("Unsupported version of libusb, please fix me");
+
+ GARY_INIT_ZERO(usb_fds, 0);
+ libusb_set_pollfd_notifiers(usb_ctx, usb_added_fd, usb_removed_fd, NULL);
+
+ const struct libusb_pollfd **fds = libusb_get_pollfds(usb_ctx);
+ ASSERT(fds);
+ for (int i=0; fds[i]; i++)
+ usb_added_fd(fds[i]->fd, fds[i]->events, NULL);
+ free(fds);
+
+ noct_read_init();
+ noct_write_init();
+}
+
+int main(int argc UNUSED, char **argv)
+{
+ log_init(argv[0]);
+ main_init();
+
+ msg(L_INFO, "Initializing USB");
+ usb_init();
+
+ msg(L_INFO, "Entering main loop");
+ main_loop();
+
+ return 0;
+}