From: notaz <notasas@gmail.com>
Date: Sun, 29 Sep 2013 11:33:57 +0000 (+0300)
Subject: mega-usb: initial code
X-Git-Url: https://notaz.gp2x.de/cgi-bin/gitweb.cgi?p=megadrive.git;a=commitdiff_plain;h=9f5a788df6754d5556056e4fb6081ab75faab383

mega-usb: initial code

Mega Everdrive USB transfer
---

diff --git a/mega-usb/Makefile b/mega-usb/Makefile
new file mode 100644
index 0000000..5c7aec3
--- /dev/null
+++ b/mega-usb/Makefile
@@ -0,0 +1,6 @@
+CFLAGS += -Wall -ggdb -O2
+
+all: mega-usb
+
+clean:
+	$(RM) mega-usb
diff --git a/mega-usb/mega-usb.c b/mega-usb/mega-usb.c
new file mode 100644
index 0000000..7217080
--- /dev/null
+++ b/mega-usb/mega-usb.c
@@ -0,0 +1,186 @@
+#define _BSD_SOURCE
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <termios.h>
+#include <unistd.h>
+
+static int setup(int fd)
+{
+	speed_t ispeed, ospeed;
+	struct termios tty;
+	int ret;
+
+	memset(&tty, 0, sizeof(tty));
+
+	ret = tcgetattr(fd, &tty);
+	if (ret != 0)
+	{
+		perror("tcgetattr");
+		return 1;
+	}
+
+	tty.c_iflag &= ~(IGNBRK | BRKINT | PARMRK | ISTRIP
+			| INLCR | IGNCR | ICRNL | IXON);
+	tty.c_oflag &= ~OPOST;
+	tty.c_lflag &= ~(ECHO | ECHONL | ICANON | ISIG | IEXTEN);
+	tty.c_cflag &= ~(CSIZE | PARENB);
+	tty.c_cflag |= CS8;
+
+	//tty.c_cc[VMIN] = 1;
+	//tty.c_cc[VTIME] = 5;            // 0.5 seconds read timeout
+
+	ret = tcsetattr(fd, TCSANOW, &tty);
+	if (ret != 0) {
+		perror("tcsetattr");
+		return ret;
+	}
+
+	return 0;
+}
+
+static int write_to_cart(int fd, const void *data, size_t size)
+{
+	int ret;
+
+	ret = write(fd, data, size);
+	if (ret != size) {
+		perror("write");
+		exit(1);
+		//return -1;
+	}
+
+	return 0;
+}
+
+static int read_from_cart(int fd, void *data, size_t size)
+{
+	int ret;
+
+	ret = read(fd, data, size);
+	if (ret != (int)size) {
+		perror("read");
+		exit(1);
+		//return -1;
+	}
+
+	return 0;
+}
+
+#define send_cmd(fd, cmd) \
+	write_to_cart(fd, cmd, sizeof(cmd) - 1)
+
+static int read_check_byte(int fd, char expect)
+{
+	char r = '0';
+	int ret;
+
+	ret = read_from_cart(fd, &r, 1);
+	if (ret != 0) {
+		fprintf(stderr, "missing response, need '%c'\n", expect);
+		return -1;
+	}
+
+	if (r != expect) {
+		fprintf(stderr, "unexpected response: '%c', need '%c'\n",
+			r, expect);
+		return -1;
+	}
+
+	return 0;
+}
+
+static int write_with_check(int fd, const void *data, size_t size, char chk)
+{
+	int ret;
+
+	ret = write_to_cart(fd, data, size);
+	if (ret)
+		return ret;
+
+	ret = read_check_byte(fd, chk);
+	if (ret != 0) {
+		if (size < 16)
+			fprintf(stderr, "data sent: '%16s'\n",
+				(const char *)data);
+		exit(1);
+		//return -1;
+	}
+
+	return 0;
+}
+
+#define send_cmd_check_k(fd, cmd) \
+	write_with_check(fd, cmd, sizeof(cmd) - 1, 'k')
+
+int main(int argc, char *argv[])
+{
+	const char *portname = "/dev/ttyUSB0";
+	char buf[0x10000];
+	size_t size;
+	int blocks;
+	FILE *f;
+	int ret;
+	int fd;
+	int i;
+
+	fd = open(portname, O_RDWR | O_NOCTTY | O_SYNC);
+	if (fd < 0) {
+		perror("open");
+		return 1;
+	}
+
+	setup(fd);
+
+	send_cmd_check_k(fd, "    *T");
+
+	if (argv[1] != NULL)
+	{
+		f = fopen(argv[1], "rb");
+		if (f == NULL)
+		{
+			perror("fopen");
+			return 1;
+		}
+		fseek(f, 0, SEEK_END);
+		size = ftell(f);
+		fseek(f, 0, SEEK_SET);
+		if (size > 0xf00000) {
+			fprintf(stderr, "size too large: %zd\n", size);
+			return 1;
+		}
+
+		blocks = (size + 0xffff) >> 16;
+		send_cmd(fd, "*g");
+		write_with_check(fd, &blocks, 1, 'k');
+
+		// at this point, 'd' will arrive even if we don't
+		// write any more data, what's the point of that?
+
+		for (i = 0; i < blocks; i++) {
+			ret = fread(buf, 1, sizeof(buf), f);
+			if (i != blocks - 1 && ret != sizeof(buf)) {
+				fprintf(stderr, "failed to read block %d/%d\n",
+					i, blocks);
+			}
+			if (ret < sizeof(buf))
+				memset(buf + ret, 0, sizeof(buf) - ret);
+
+			write_to_cart(fd, buf, sizeof(buf));
+		}
+
+		ret = read_check_byte(fd, 'd');
+		if (ret)
+			return 1;
+
+		send_cmd_check_k(fd, "*rm");
+	}
+
+	printf("all ok\n");
+
+	return 0;
+}