view cp2102/read_eeprom_main.c @ 68:5cbde3c80c24

fteeprom-{erase,prog}: detach logic: change to detach by default As it turns out, detaching all ttyUSB interfaces of a multichannel device does not require outside knowledge of how many channels there are, as in our previous -d option design that is being removed here - instead we can read the bNumInterfaces constant from the USB device's config descriptor and thus know how many interfaces there are in total. Based on this discovery, change the design of fteeprom-{erase,prog} as follows: * remove -d option; * flip the default to where we detach all interfaces by default; * add -n option to NOT detach any interfaces.
author Mychaela Falconia <falcon@freecalypso.org>
date Wed, 13 Sep 2023 06:37:03 +0000
parents d4d3531d342a
children a378bf95c26c
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/*
 * This program locates a CP2102 device via libusb, reads its internal
 * 1024-byte EEPROM and emits (on stdout) an image of this EEPROM
 * in the same Intel HEX format as used by cp210x-program-1.0,
 * the Python-language tool from 2014.
 */

#include <sys/types.h>
#include <string.h>
#include <strings.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <usb.h>
#include "../libuwrap/find_dev.h"
#include "cp210x_defs.h"

u_char eeprom[SIZE_EEPROM];

main(argc, argv)
	char **argv;
{
	struct usb_device *dev;
	usb_dev_handle *usbh;

	if (argc != 2) {
		fprintf(stderr, "usage: %s device-selector\n", argv[0]);
		exit(1);
	}
	dev = find_usbdev_by_desc_string(argv[1]);
	if (!dev) {
		fprintf(stderr, "error: specified USB device not found\n");
		exit(1);
	}
	usbh = usb_open(dev);
	if (!usbh) {
		fprintf(stderr, "error: usb_open() failed\n");
		exit(1);
	}
	read_eeprom(usbh);
	usb_close(usbh);
	intel_hex_out(eeprom, stdout);
	exit(0);
}