Rework for new eismulitplexer pcb

add documentation
add pkg-config files

eismultiplexer.c

@@ -0,0 +1,113 @@
+/**
+* Copyright (C) 2023 Carl Klemm
+*
+* This program is free software; you can redistribute it and/or
+* modify it under the terms of the GNU General Public License
+* version 3 as published by the Free Software Foundation.
+*
+* 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., 51 Franklin Street, Fifth Floor,
+* Boston, MA  02110-1301, USA.
+*/
+
+#define _POSIX_C_SOURCE 199309L
+#include "eismultiplexer.h"
+#include "usbshm.h"
+#include <stdlib.h>
+#include <time.h>
+
+static void usleep(uint64_t microseconds)
+{
+	struct timespec ts;
+	ts.tv_sec = microseconds / 1000000;
+	ts.tv_nsec = (microseconds % 1000000) * 1000;
+	nanosleep(&ts, NULL);
+}
+
+static void dataCallback(uint8_t request, unsigned char* data, size_t length, void* user_data)
+{
+	struct eismulitplexer* muliplexer = user_data;
+
+	if(length >= 1)
+		muliplexer->activeChannels = data[0];
+
+	sem_post(&muliplexer->readSem);
+}
+
+int eismulitplexer_connect(struct eismulitplexer* muliplexer, int serial)
+{
+	int ret;
+	muliplexer->priv = malloc(sizeof(*muliplexer->priv));
+	if(!muliplexer->priv)
+		return -1;
+	
+	ret = usbshm_init(muliplexer->priv, &dataCallback, muliplexer);
+	if(ret)
+		return -2;
+	
+	ret = usbshm_open(muliplexer->priv, 0xfe17, 0x07dc , NULL);
+	if(ret)
+		return -3;
+
+	ret = sem_init(&muliplexer->readSem, 0, 0);
+	if(ret)
+		return -4;
+	return 0;
+}
+
+int eismulitplexer_connect_channel_exclusive(struct eismulitplexer* muliplexer, channel_t channel)
+{
+	uint16_t wValue;
+	// we compile with fno-strict-aliasing
+	uint8_t* wValChar = (uint8_t*)&wValue;
+	wValChar[0] = channel;
+	wValChar[1] = 0;
+	int ret;
+	while((ret = usbshm_writeControlTransfer(muliplexer->priv, 2, NULL, 0, wValue, 0)) == USBSHM_ERROR_AGAIN)
+		usleep(1000000);
+	return ret;
+}
+
+int eismulitplexer_connect_channel(struct eismulitplexer* muliplexer, channel_t channel)
+{
+	channel_t channels = eismulitplexer_get_connected(muliplexer);
+	channels |= channel;
+	return eismulitplexer_connect_channel_exclusive(muliplexer, channels);
+}
+
+int eismulitplexer_disconnect_channel(struct eismulitplexer* muliplexer, channel_t channel)
+{
+	channel_t channels = eismulitplexer_get_connected(muliplexer);
+	channels &= ~channel;
+	return eismulitplexer_connect_channel_exclusive(muliplexer, channels);
+}
+
+channel_t eismulitplexer_get_connected(struct eismulitplexer* muliplexer)
+{
+	usbshm_readControlTransfer(muliplexer->priv, 3, 1);
+	sem_wait(&muliplexer->readSem);
+	return muliplexer->activeChannels;
+}
+
+
+int eismulitplexer_set_led(struct eismulitplexer* muliplexer, bool on)
+{
+	int ret;
+	while((ret = usbshm_writeControlTransfer(muliplexer->priv, on, NULL, 0, 0, 0)) == USBSHM_ERROR_AGAIN)
+		usleep(1000000);
+	return ret;
+}
+
+void eismulitplexer_disconnect(struct eismulitplexer* muliplexer)
+{
+	usbshm_distroy(muliplexer->priv);
+	free(muliplexer->priv);
+	muliplexer->priv = NULL;
+	sem_destroy(&muliplexer->readSem);
+}