/*****************************************************************************
* submit a channel rpc call to the UART
* If buffer slot is available, return immediately.
* Otherwise wait until slot is available, then return
* (while data is transferred in the background)
*
* Note: submitter must check buf_is_empty() for true or buf_wait_free()
* before reuse or freeing the memory!
*
* callback is called from delay() context when the response has been
* received
*/
void serial_submit_call(void *epdata, int8_t channelno, packet_t *txbuf, packet_t *rxbuf,
uint8_t (*callback)(int8_t channelno, int8_t errnum, packet_t *packet)) {
if (channelno < 0) {
debug_printf("!!!! submit with channelno=%d\n", channelno);
}
if (txbuf->chan < 0) {
debug_printf("!!!! submit with packet->chan=%d\n", txbuf->chan);
}
// check rx slot
// wait / loop until receive buffer is being freed by interrupt routine
int8_t channelpos = -1;
while (channelpos < 0) {
for (uint8_t i = 0; i < NUMBER_OF_SLOTS; i++) {
// note: take either a free one or overwrite an existing one
// the latter case is only used for rtconfig_pullconfig()
// sending a new request
if (rx_channels[i].channelno < 0
|| rx_channels[i].channelno == channelno) {
channelpos = i;
break;
}
}
serial_delay();
}
rx_channels[channelpos].channelno = channelno;
rx_channels[channelpos].rxpacket = rxbuf;
rx_channels[channelpos].callback = callback;
// send request
serial_submit(epdata, txbuf);
}
static int serial_read (void)
{
FILE *fh;
char buffer[1024];
/* there are a variety of names for the serial device */
if ((fh = fopen ("/proc/tty/driver/serial", "r")) == NULL &&
(fh = fopen ("/proc/tty/driver/ttyS", "r")) == NULL)
{
char errbuf[1024];
WARNING ("serial: fopen: %s",
sstrerror (errno, errbuf, sizeof (errbuf)));
return (-1);
}
while (fgets (buffer, sizeof (buffer), fh) != NULL)
{
derive_t rx = 0;
derive_t tx = 0;
_Bool have_rx = 0, have_tx = 0;
size_t len;
char *fields[16];
int numfields;
int i;
numfields = strsplit (buffer, fields, STATIC_ARRAY_SIZE (fields));
if (numfields < 6)
continue;
/*
* 0: uart:16550A port:000003F8 irq:4 tx:0 rx:0
* 1: uart:16550A port:000002F8 irq:3 tx:0 rx:0
*/
len = strlen (fields[0]);
if (len < 2)
continue;
if (fields[0][len - 1] != ':')
continue;
fields[0][len - 1] = 0;
for (i = 1; i < numfields; i++)
{
len = strlen (fields[i]);
if (len < 4)
continue;
if (strncmp (fields[i], "tx:", 3) == 0)
{
if (strtoderive (fields[i] + 3, &tx) == 0)
have_tx = 1;
}
else if (strncmp (fields[i], "rx:", 3) == 0)
{
if (strtoderive (fields[i] + 3, &rx) == 0)
have_rx = 1;
}
}
if (have_rx && have_tx)
serial_submit (fields[0], rx, tx);
}
fclose (fh);
return (0);
} /* int serial_read */
