--- /dev/null
+/*
+ * Copyright © 2008 Keith Packard <keithp@keithp.com>
+ *
+ * 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, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ */
+
+#include "ccdbg.h"
+
+static void
+say(char *name, uint8_t bits)
+{
+ printf("%s: ", name);
+ if (bits & CC_RESET_N)
+ printf ("R ");
+ else
+ printf (". ");
+ if (bits & CC_CLOCK)
+ printf ("C ");
+ else
+ printf (". ");
+ if (bits & CC_DATA)
+ printf ("D\n");
+ else
+ printf (".\n");
+}
+
+static void
+_cccp_write(struct ccdbg *dbg, uint8_t mask, uint8_t value)
+{
+ uint16_t set;
+ int ret;
+
+ set = (mask) | (value << 8);
+ dbg->debug_data = (dbg->debug_data & ~mask) | (value & mask);
+ ret = ioctl(dbg->fd, CP2101_IOCTL_GPIOSET, &set);
+ if (ret < 0)
+ perror("CP2101_IOCTL_GPIOSET");
+}
+
+void
+cccp_write(struct ccdbg *dbg, uint8_t mask, uint8_t value)
+{
+ _cccp_write(dbg, mask, value);
+// say("w", dbg->debug_data);
+}
+
+uint8_t
+cccp_read_all(struct ccdbg *dbg)
+{
+ int ret;
+ uint8_t get;
+ ret = ioctl(dbg->fd, CP2101_IOCTL_GPIOGET, &get);
+ if (ret < 0) {
+ perror("CP2101_IOCTL_GPIOGET");
+ get = 0;
+ }
+ return get;
+}
+
+uint8_t
+cccp_read(struct ccdbg *dbg, uint8_t mask)
+{
+ uint8_t pull_up;
+ uint8_t get;
+
+ /* tri-state the bits of interest */
+ pull_up = (~dbg->debug_data) & mask;
+ if (pull_up)
+ _cccp_write(dbg, pull_up, pull_up);
+ get = cccp_read_all(dbg);
+ say("\t\tr", get);
+ return get & mask;
+}
+
+void
+cccp_init(struct ccdbg *dbg)
+{
+ /* set all of the GPIOs to a known state */
+ cccp_write(dbg, 0xf, 0xf);
+}
+
+void
+cccp_fini(struct ccdbg *dbg)
+{
+ /* set all of the GPIOs to a known state */
+ cccp_write(dbg, 0xf, 0xf);
+ dbg->clock = 1;
+}
+
+cccp_open()
+{
+ dbg->fd = open("/dev/ttyUSB0", 2);
+ if (dbg->fd < 0) {
+ perror(file);
+ free(dbg);
+ return NULL;
+ }
+ cccp_init(dbg);
+ cccp_write(dbg, CC_CLOCK, CC_CLOCK);
+}