complete gpio_init(), room for improvement

1 files changed, 102 insertions, 88 deletions

diff --git a/freeonebook.c b/freeonebook.c
index e9be2e2..584013f 100644
--- a/freeonebook.c
+++ b/freeonebook.c
@@ -1,12 +1,14 @@
 #include <stdint.h>
 #include <stdio.h>
+#include <string.h>
 #include <fcntl.h>
 #include <unistd.h>
 
-#define GPIO_EXPORT "/sys/class/gpio/export"
+#define GPIO_BASEDIR	"/sys/class/gpio"
+#define GPIO_EXPORT	GPIO_BASEDIR "/export"
 
-#define ENABLE_LEFT_PATH "/sys/class/gpio/gpio5/value"
-#define ENABLE_RIGHT_PATH "/sys/class/gpio/gpio4/value"
+#define ENABLE_LEFT_PATH	GPIO_BASEDIR "/gpio5/value"
+#define ENABLE_RIGHT_PATH	GPIO_BASEDIR "/gpio4/value"
 
 #define ENABLE_VALUE "1"
 
@@ -24,101 +26,111 @@ void enable_displays(void)
 	close(right);
 }
 
+void gpio_write(int port, const char *field, const char *value)
+{
+	char path[256];
+	sprintf(path, "%s/gpio%d/%s", GPIO_BASEDIR, field);
+	int fd = open(path, O_WRONLY);
+	write(fd, value, strlen(value));
+	close(fd);
+}
+
 void gpio_init(void)
 {
 	struct {
 		uint8_t port;
 		enum { in, out } direction;
+		uint8_t value;
 	} ports[] = {
-		{ 100, in },	/* 4a58 */
+		{ 100, in },
 		{ 91, in },
 		{ 96, in },
 		{ 89, in },
 			{ 95, in },
 			{ 92, in },
-		{ 108, out },	/* 4aec */
-		{ 94, out },
-			{ 101, out },	/* 95, 92 */
+				{ 108, out, 0 },
+				{ 94, out, 0 },
+				{ 101, out, 0 },	/* 95, 92 */
 		{ 5, out },
 		{ 4, out },
 		{ 93, in },
-		{ 98, out },
-		{ 90, out },
+		{ 98, out, 1 },
+				{ 90, out, 1 },			/* 108, 94, 101 */
 		{ 88, in },
-		{ 0, out },
-		{ 1, out },
-		{ 2, out },
-		{ 3, out },
-		{ 6, out },
-		{ 28, out },
-		{ 29, out },
-		{ 30, out },
-		{ 33, out },
-		{ 37, out },
-		{ 38, out },
-		{ 47, out },
-		{ 48, out },
-		{ 49, out },
-		{ 50, out },
-		{ 51, out },
-		{ 52, out },
-		{ 53, out },
-		{ 54, out },
-		{ 55, out },
-		{ 56, out },
-		{ 57, out },
-		{ 58, out },
-		{ 59, out },
-		{ 60, out },
-		{ 61, out },
-		{ 62, out },
-		{ 63, out },
-		{ 64, out },
-		{ 65, out },
-		{ 66, out },
-		{ 67, out },
-		{ 68, out },
-		{ 69, out },
-		{ 70, out },
-		{ 71, out },
-		{ 72, out },
-		{ 73, out },
-		{ 74, out },
-				{ 75, out },	/* not enabled */
-		{ 78, out },
-		{ 79, out },
-		{ 86, out },
-		{ 87, out },
-		{ 97, out },
-		{ 99, out },
-		{ 104, out },
-		{ 105, out },
-		{ 106, out },
-		{ 107, out },
-		{ 109, out },
-		{ 110, out },
-		{ 111, out },
-		{ 112, out },
-		{ 113, out },
-		{ 114, out },
-		{ 115, out },
-		{ 116, out },
-		{ 117, out },
-		{ 118, out },
-		{ 119, out },
-		{ 120, out },
-		{ 121, out },
-		{ 122, out },
-		{ 135, out },
-		{ 137, out },
-		{ 138, out },
-		{ 140, out },
-		{ 144, out },
-		{ 145, out },
-		{ 146, out },
-		{ 147, out },
-		{ 148, out },
-		{ 149, out },
+		{ 0, out, 0 },
+		{ 1, out, 0 },
+		{ 2, out, 0 },
+		{ 3, out, 0 },
+		{ 6, out, 0 },
+		{ 28, out, 0 },
+		{ 29, out, 0 },
+		{ 30, out, 0 },
+		{ 33, out, 0 },
+		{ 37, out, 0 },
+		{ 38, out, 0 },
+		{ 47, out, 0 },
+		{ 48, out, 0 },
+		{ 49, out, 0 },
+		{ 50, out, 0 },
+		{ 51, out, 0 },
+		{ 52, out, 0 },
+		{ 53, out, 0 },
+		{ 54, out, 0 },
+		{ 55, out, 0 },
+		{ 56, out, 0 },
+		{ 57, out, 0 },
+		{ 58, out, 0 },
+		{ 59, out, 0 },
+		{ 60, out, 0 },
+		{ 61, out, 0 },
+		{ 62, out, 0 },
+		{ 63, out, 0 },
+		{ 64, out, 0 },
+		{ 65, out, 0 },
+		{ 66, out, 0 },
+		{ 67, out, 0 },
+		{ 68, out, 0 },
+		{ 69, out, 0 },
+		{ 70, out, 0 },
+		{ 71, out, 0 },
+		{ 72, out, 0 },
+		{ 73, out, 0 },
+		{ 74, out, 0 },
+				{ 75, out, 0 },	/* not enabled */
+		{ 78, out, 0 },
+		{ 79, out, 0 },
+		{ 86, out, 0 },
+		{ 87, out, 0 },
+		{ 97, out, 0 },
+		{ 99, out, 0 },
+		{ 104, out, 0 },
+		{ 105, out, 0 },
+		{ 106, out, 0 },
+		{ 107, out, 0 },
+		{ 109, out, 0 },
+		{ 110, out, 0 },
+		{ 111, out, 0 },
+		{ 112, out, 0 },
+		{ 113, out, 0 },
+		{ 114, out, 0 },
+		{ 115, out, 0 },
+		{ 116, out, 0 },
+		{ 117, out, 0 },
+		{ 118, out, 0 },
+		{ 119, out, 0 },
+		{ 120, out, 0 },
+		{ 121, out, 0 },
+		{ 122, out, 0 },
+		{ 135, out, 0 },
+		{ 137, out, 0 },
+		{ 138, out, 0 },
+		{ 140, out, 0 },
+		{ 144, out, 0 },
+		{ 145, out, 0 },
+		{ 146, out, 0 },
+		{ 147, out, 0 },
+		{ 148, out, 0 },
+		{ 149, out, 0 },
 	};
 	int gpio_export = open(GPIO_EXPORT, O_WRONLY);
 	for (int i = 0; i < sizeof(ports) / sizeof(ports[0]); i++) {
@@ -128,11 +140,13 @@ void gpio_init(void)
 	close(gpio_export);
 
 	for (int i = 0; i < sizeof(ports) / sizeof(ports[0]); i++) {
-		char path[256];
-		sprintf(path, "/sys/class/gpio/gpio%hhd/direction", ports[i].port);
-		int dir = open(path, O_WRONLY);
-		dprintf(dir, "%s", ports[i].direction == in ? "in" : "out");
-		close(dir);
+		gpio_write(ports[i].port, "direction", ports[i].direction == in ? "in" : "out");
+	}
+
+	for (int i = 0; i < sizeof(ports) / sizeof(ports[0]); i++) {
+		if (ports[i].direction == out) {
+			gpio_write(ports[i].port, "value", ports[i].value == 1 ? "1" : "0");
+		}
 	}
 }