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-rw-r--r--common/recipes-lib/gpio/files/src/Makefile27
-rw-r--r--common/recipes-lib/gpio/files/src/gpio.c107
-rw-r--r--common/recipes-lib/gpio/files/src/gpio.h42
3 files changed, 176 insertions, 0 deletions
diff --git a/common/recipes-lib/gpio/files/src/Makefile b/common/recipes-lib/gpio/files/src/Makefile
new file mode 100644
index 0000000..0b605fc
--- /dev/null
+++ b/common/recipes-lib/gpio/files/src/Makefile
@@ -0,0 +1,27 @@
+# Copyright 2015-present Facebook. All Rights Reserved.
+#
+# This program file 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; version 2 of the License.
+#
+# 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 in a file named COPYING; if not, write to the
+# Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor,
+# Boston, MA 02110-1301 USA
+
+lib: libgpio.so
+
+libgpio.so: gpio.c
+ $(CC) $(CFLAGS) -fPIC -c -o gpio.o gpio.c
+ $(CC) -shared -o libgpio.so gpio.o -lc
+
+.PHONY: clean
+
+clean:
+ rm -rf *.o libgpio.so
diff --git a/common/recipes-lib/gpio/files/src/gpio.c b/common/recipes-lib/gpio/files/src/gpio.c
new file mode 100644
index 0000000..9c1f7a2
--- /dev/null
+++ b/common/recipes-lib/gpio/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 <openbmc/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;
+}
diff --git a/common/recipes-lib/gpio/files/src/gpio.h b/common/recipes-lib/gpio/files/src/gpio.h
new file mode 100644
index 0000000..3303986
--- /dev/null
+++ b/common/recipes-lib/gpio/files/src/gpio.h
@@ -0,0 +1,42 @@
+/*
+ * 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.
+ */
+#ifndef GPIO_H
+#define GPIO_H
+
+typedef struct {
+ int gs_gpio;
+ int gs_fd;
+} gpio_st;
+
+typedef enum {
+ GPIO_DIRECTION_IN,
+ GPIO_DIRECTION_OUT,
+} gpio_direction_en;
+
+typedef enum {
+ GPIO_VALUE_LOW = 0,
+ GPIO_VALUE_HIGH = 1,
+} gpio_value_en;
+
+int gpio_open(gpio_st* g, int gpio);
+void gpio_close(gpio_st *g);
+gpio_value_en gpio_read(gpio_st *g);
+void gpio_write(gpio_st *g, gpio_value_en v);
+int gpio_change_direction(gpio_st *g, gpio_direction_en dir);
+
+#endif
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