split GPIO stuff into separate file

4 files changed, 177 insertions, 132 deletions

diff --git a/Makefile b/Makefile
index dbecf8c..2839e99 100644
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,11 @@
 CC=arm-linux-gnueabihf-gcc
 CFLAGS=-Wall -Wextra
 
-freeonebook: freeonebook.o
+freeonebook: freeonebook.o gpio.o
+
+freeonebook.o: freeonebook.c gpio.h
+
+gpio.o: gpio.c gpio.h
 
 clean:
 	rm -f freeonebook *.o
diff --git a/freeonebook.c b/freeonebook.c
index 0dba0cf..86cf470 100644
--- a/freeonebook.c
+++ b/freeonebook.c
@@ -4,6 +4,8 @@
 #include <fcntl.h>
 #include <unistd.h>
 
+#include "gpio.h"
+
 #define BUTTON_SPECIAL		89
 #define BUTTON_PREVBOOK		91
 #define BUTTON_PREVPAGE		92
@@ -11,142 +13,13 @@
 #define BUTTON_NEXTCHAPTER	96
 #define BUTTON_NEXTBOOK		100
 
-#define GPIO_BASEDIR	"/sys/class/gpio"
-#define GPIO_EXPORT	GPIO_BASEDIR "/export"
-
 #define ENABLE_LEFT_DISPLAY	5
 #define ENABLE_RIGHT_DISPLAY	4
 
-void gpio_write(int port, const char *field, const char *value)
-{
-	char path[256];
-	sprintf(path, "%s/gpio%d/%s", GPIO_BASEDIR, port, field);
-	int fd = open(path, O_WRONLY);
-	ssize_t n = write(fd, value, strlen(value));
-	close(fd);
-	printf("write '%s' to '%s' => %d\n", value, path, n);
-}
-
 void enable_displays(void)
 {
-	gpio_write(ENABLE_LEFT_DISPLAY, "value", "1");
-	gpio_write(ENABLE_RIGHT_DISPLAY, "value", "1");
-}
-
-void gpio_init(void)
-{
-	struct {
-		uint8_t port;
-		enum { in, out } direction;
-		uint8_t value;
-	} ports[] = {
-		{ 100, in, 0 },
-		{ 91, in, 0 },
-		{ 96, in, 0 },
-		{ 89, in, 0 },
-			{ 95, in, 0 },
-			{ 92, in, 0 },
-				{ 108, out, 0 },
-				{ 94, out, 0 },
-				{ 101, out, 0 },	/* 95, 92 */
-		{ 5, out, 0 },
-		{ 4, out, 0 },
-		{ 93, in, 0 },
-		{ 98, out, 1 },
-				{ 90, out, 1 },			/* 108, 94, 101 */
-		{ 88, in, 0 },
-		{ 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 (size_t i = 0; i < sizeof(ports) / sizeof(ports[0]); i++) {
-		printf("enabling port %d\n", ports[i].port);
-		dprintf(gpio_export, "%d", ports[i].port);
-	}
-	close(gpio_export);
-
-	for (size_t i = 0; i < sizeof(ports) / sizeof(ports[0]); i++) {
-		gpio_write(ports[i].port, "direction", ports[i].direction == in ? "in" : "out");
-	}
-
-	for (size_t 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");
-		}
-	}
+	gpio_set(ENABLE_LEFT_DISPLAY);
+	gpio_set(ENABLE_RIGHT_DISPLAY);
 }
 
 int main(int argc, char *argv[])
diff --git a/gpio.c b/gpio.c
new file mode 100644
index 0000000..da2ffef
--- /dev/null
+++ b/gpio.c
@@ -0,0 +1,159 @@
+#include "gpio.h"
+
+#include <fcntl.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+#define GPIO_BASEDIR	"/sys/class/gpio"
+#define GPIO_EXPORT	GPIO_BASEDIR "/export"
+
+#define GPIO_IN		"in"
+#define GPIO_INIT_LOW	"GPIO_INIT_LOW"
+#define GPIO_INIT_HIGH	"GPIO_INIT_HIGH"
+
+static int gpio_open(int port, const char *field, int flags)
+{
+	char path[256];
+	sprintf(path, "%s/gpio%d/%s", GPIO_BASEDIR, port, field);
+	return open(path, flags);
+}
+
+int gpio_get(int port)
+{
+	char c;
+	int fd = gpio_open(port, "value", O_RDONLY);
+	read(fd, &c, 1);
+	close(fd);
+	if (c == '0') {
+		return 0;
+	}
+	return 1;
+}
+
+void gpio_set(int port)
+{
+	int fd = gpio_open(port, "value", O_WRONLY);
+	write(fd, "1", 1);
+	close(fd);
+}
+
+void gpio_clear(int port)
+{
+	int fd = gpio_open(port, "value", O_WRONLY);
+	write(fd, "0", 1);
+	close(fd);
+}
+
+static void gpio_enable(int export_fd, int port, const char *state)
+{
+	dprintf(export_fd, "%d", port);
+	int fd = gpio_open(port, "direction", O_WRONLY);
+	write(fd, "state", strlen(state));
+	close(fd);
+}
+
+void gpio_init(void)
+{
+	struct {
+		uint8_t port;
+		const char *initstate;
+	} ports[] = {
+		{ 100, GPIO_IN },
+		{ 91, GPIO_IN },
+		{ 96, GPIO_IN },
+		{ 89, GPIO_IN },
+			{ 95, GPIO_IN },
+			{ 92, GPIO_IN },
+				{ 108, GPIO_INIT_LOW },
+				{ 94, GPIO_INIT_LOW },
+				{ 101, GPIO_INIT_LOW },	/* 95, 92 */
+		{ 5, GPIO_INIT_LOW },
+		{ 4, GPIO_INIT_LOW },
+		{ 93, GPIO_IN },
+		{ 98, GPIO_INIT_HIGH },
+				{ 90, GPIO_INIT_HIGH },	/* 108, 94, 101 */
+		{ 88, GPIO_IN },
+		{ 0, GPIO_INIT_LOW },
+		{ 1, GPIO_INIT_LOW },
+		{ 2, GPIO_INIT_LOW },
+		{ 3, GPIO_INIT_LOW },
+		{ 6, GPIO_INIT_LOW },
+		{ 28, GPIO_INIT_LOW },
+		{ 29, GPIO_INIT_LOW },
+		{ 30, GPIO_INIT_LOW },
+		{ 33, GPIO_INIT_LOW },
+		{ 37, GPIO_INIT_LOW },
+		{ 38, GPIO_INIT_LOW },
+		{ 47, GPIO_INIT_LOW },
+		{ 48, GPIO_INIT_LOW },
+		{ 49, GPIO_INIT_LOW },
+		{ 50, GPIO_INIT_LOW },
+		{ 51, GPIO_INIT_LOW },
+		{ 52, GPIO_INIT_LOW },
+		{ 53, GPIO_INIT_LOW },
+		{ 54, GPIO_INIT_LOW },
+		{ 55, GPIO_INIT_LOW },
+		{ 56, GPIO_INIT_LOW },
+		{ 57, GPIO_INIT_LOW },
+		{ 58, GPIO_INIT_LOW },
+		{ 59, GPIO_INIT_LOW },
+		{ 60, GPIO_INIT_LOW },
+		{ 61, GPIO_INIT_LOW },
+		{ 62, GPIO_INIT_LOW },
+		{ 63, GPIO_INIT_LOW },
+		{ 64, GPIO_INIT_LOW },
+		{ 65, GPIO_INIT_LOW },
+		{ 66, GPIO_INIT_LOW },
+		{ 67, GPIO_INIT_LOW },
+		{ 68, GPIO_INIT_LOW },
+		{ 69, GPIO_INIT_LOW },
+		{ 70, GPIO_INIT_LOW },
+		{ 71, GPIO_INIT_LOW },
+		{ 72, GPIO_INIT_LOW },
+		{ 73, GPIO_INIT_LOW },
+		{ 74, GPIO_INIT_LOW },
+				{ 75, GPIO_INIT_LOW },	/* not enabled */
+		{ 78, GPIO_INIT_LOW },
+		{ 79, GPIO_INIT_LOW },
+		{ 86, GPIO_INIT_LOW },
+		{ 87, GPIO_INIT_LOW },
+		{ 97, GPIO_INIT_LOW },
+		{ 99, GPIO_INIT_LOW },
+		{ 104, GPIO_INIT_LOW },
+		{ 105, GPIO_INIT_LOW },
+		{ 106, GPIO_INIT_LOW },
+		{ 107, GPIO_INIT_LOW },
+		{ 109, GPIO_INIT_LOW },
+		{ 110, GPIO_INIT_LOW },
+		{ 111, GPIO_INIT_LOW },
+		{ 112, GPIO_INIT_LOW },
+		{ 113, GPIO_INIT_LOW },
+		{ 114, GPIO_INIT_LOW },
+		{ 115, GPIO_INIT_LOW },
+		{ 116, GPIO_INIT_LOW },
+		{ 117, GPIO_INIT_LOW },
+		{ 118, GPIO_INIT_LOW },
+		{ 119, GPIO_INIT_LOW },
+		{ 120, GPIO_INIT_LOW },
+		{ 121, GPIO_INIT_LOW },
+		{ 122, GPIO_INIT_LOW },
+		{ 135, GPIO_INIT_LOW },
+		{ 137, GPIO_INIT_LOW },
+		{ 138, GPIO_INIT_LOW },
+		{ 140, GPIO_INIT_LOW },
+		{ 144, GPIO_INIT_LOW },
+		{ 145, GPIO_INIT_LOW },
+		{ 146, GPIO_INIT_LOW },
+		{ 147, GPIO_INIT_LOW },
+		{ 148, GPIO_INIT_LOW },
+		{ 149, GPIO_INIT_LOW },
+	};
+
+	int gpio_export = open(GPIO_EXPORT, O_WRONLY);
+	for (size_t i = 0; i < sizeof(ports) / sizeof(ports[0]); i++) {
+		gpio_enable(gpio_export, ports[i].port, ports[i].initstate);
+	}
+	close(gpio_export);
+}
diff --git a/gpio.h b/gpio.h
new file mode 100644
index 0000000..a0d3271
--- /dev/null
+++ b/gpio.h
@@ -0,0 +1,9 @@
+#ifndef GPIO_H
+#define GPIO_H
+
+int gpio_get(int port);
+void gpio_set(int port);
+void gpio_clear(int port);
+void gpio_init(void);
+
+#endif