1 files changed, 107 insertions, 0 deletions
diff --git a/meta-facebook/meta-wedge/recipes-wedge/bitbang/files/src/gpio.c b/meta-facebook/meta-wedge/recipes-wedge/bitbang/files/src/gpio.c
new file mode 100644
index 0000000..026aebc
--- /dev/null
+++ b/meta-facebook/meta-wedge/recipes-wedge/bitbang/files/src/gpio.c
@@ -0,0 +1,107 @@
+/*
+ * Copyright 2014-present Facebook. All Rights Reserved.
+ *
+ * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+//#define DEBUG
+//#define VERBOSE
+
+#include "gpio.h"
+
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/errno.h>
+
+#include "facebook/log.h"
+
+void gpio_init_default(gpio_st *g) {
+  g->gs_gpio = -1;
+  g->gs_fd = -1;
+}
+
+int gpio_open(gpio_st *g, int gpio)
+{
+  char buf[128];
+  int rc;
+
+  snprintf(buf, sizeof(buf), "/sys/class/gpio/gpio%u/value", gpio);
+  rc = open(buf, O_RDWR);
+  if (rc == -1) {
+    rc = errno;
+    LOG_ERR(rc, "Failed to open %s", buf);
+    return -rc;
+  }
+  g->gs_fd = rc;
+  g->gs_gpio = gpio;
+  return 0;
+}
+
+void gpio_close(gpio_st *g)
+{
+  if (g && g->gs_fd != -1) {
+    close(g->gs_fd);
+  }
+  gpio_init_default(g);
+}
+
+gpio_value_en gpio_read(gpio_st *g)
+{
+  char buf[32] = {0};
+  gpio_value_en v;
+  lseek(g->gs_fd, 0, SEEK_SET);
+  read(g->gs_fd, buf, sizeof(buf));
+  v = atoi(buf) ? GPIO_VALUE_HIGH : GPIO_VALUE_LOW;
+  LOG_VER("read gpio=%d value=%d %d", g->gs_gpio, atoi(buf), v);
+  return v;
+}
+
+void gpio_write(gpio_st *g, gpio_value_en v)
+{
+  lseek(g->gs_fd, 0, SEEK_SET);
+  write(g->gs_fd, (v == GPIO_VALUE_HIGH) ? "1" : "0", 1);
+  LOG_VER("write gpio=%d value=%d", g->gs_gpio, v);
+}
+
+int gpio_change_direction(gpio_st *g, gpio_direction_en dir)
+{
+  char buf[128];
+  char *val;
+  int fd = -1;
+  int rc = 0;
+
+  snprintf(buf, sizeof(buf), "/sys/class/gpio/gpio%u/direction", g->gs_gpio);
+  fd = open(buf, O_WRONLY);
+  if (fd == -1) {
+    rc = errno;
+    LOG_ERR(rc, "Failed to open %s", buf);
+    return -rc;
+  }
+
+  val = (dir == GPIO_DIRECTION_IN) ? "in" : "out";
+  write(fd, val, strlen(val));
+
+  LOG_VER("change gpio=%d direction=%s", g->gs_gpio, val);
+
+ out:
+  if (fd != -1) {
+    close(fd);
+  }
+  return -rc;
+}