/*
* Routine that handles all the logic needed to parse out the message from the remote.
*/
static void keyspan_check_data(struct usb_keyspan *remote)
{
int i;
int found = 0;
struct keyspan_message message;
switch(remote->stage) {
case 0:
/*
* In stage 0 we want to find the start of a message. The remote sends a 0xFF as filler.
* So the first byte that isn't a FF should be the start of a new message.
*/
for (i = 0; i < RECV_SIZE && remote->in_buffer[i] == GAP; ++i);
if (i < RECV_SIZE) {
memcpy(remote->data.buffer, remote->in_buffer, RECV_SIZE);
remote->data.len = RECV_SIZE;
remote->data.pos = 0;
remote->data.tester = 0;
remote->data.bits_left = 0;
remote->stage = 1;
}
break;
case 1:
/*
* Stage 1 we should have 16 bytes and should be able to detect a
* SYNC. The SYNC is 14 bits, 7 0's and then 7 1's.
*/
memcpy(remote->data.buffer + remote->data.len, remote->in_buffer, RECV_SIZE);
remote->data.len += RECV_SIZE;
found = 0;
while ((remote->data.bits_left >= 14 || remote->data.pos < remote->data.len) && !found) {
for (i = 0; i < 8; ++i) {
if (keyspan_load_tester(remote, 14) != 0) {
remote->stage = 0;
return;
}
if ((remote->data.tester & SYNC_MASK) == SYNC) {
remote->data.tester = remote->data.tester >> 14;
remote->data.bits_left -= 14;
found = 1;
break;
} else {
remote->data.tester = remote->data.tester >> 1;
--remote->data.bits_left;
}
}
}
static void keyspan_check_data(struct usb_keyspan *remote)
{
int i;
int found = 0;
struct keyspan_message message;
switch(remote->stage) {
case 0:
for (i = 0; i < RECV_SIZE && remote->in_buffer[i] == GAP; ++i);
if (i < RECV_SIZE) {
memcpy(remote->data.buffer, remote->in_buffer, RECV_SIZE);
remote->data.len = RECV_SIZE;
remote->data.pos = 0;
remote->data.tester = 0;
remote->data.bits_left = 0;
remote->stage = 1;
}
break;
case 1:
memcpy(remote->data.buffer + remote->data.len, remote->in_buffer, RECV_SIZE);
remote->data.len += RECV_SIZE;
found = 0;
while ((remote->data.bits_left >= 14 || remote->data.pos < remote->data.len) && !found) {
for (i = 0; i < 8; ++i) {
if (keyspan_load_tester(remote, 14) != 0) {
remote->stage = 0;
return;
}
if ((remote->data.tester & SYNC_MASK) == SYNC) {
remote->data.tester = remote->data.tester >> 14;
remote->data.bits_left -= 14;
found = 1;
break;
} else {
remote->data.tester = remote->data.tester >> 1;
--remote->data.bits_left;
}
}
}