Note that this change increases the risk of rx_pending vs. rx_active
races.
---
softusb-input/main.c | 33 ++++++++++++++++++++++-----------
1 files changed, 22 insertions(+), 11 deletions(-)
diff --git a/softusb-input/main.c b/softusb-input/main.c
index bf50695..1bb6bf8 100644
--- a/softusb-input/main.c
+++ b/softusb-input/main.c
@@ -123,7 +123,18 @@ static const char ack_error[] PROGMEM = "ACK: ";
static const char timeout_error[] PROGMEM = "RX timeout error\n";
static const char bitstuff_error[] PROGMEM = "RX bitstuff error\n";
-#define WAIT_RX(first, end) \
+#define WAIT_ACTIVE() \
+ do { \
+ unsigned timeout = 0x200; \
+ while(!rio8(SIE_RX_ACTIVE)) { \
+ if(!--timeout) \
+ goto timeout; \
+ if(rio8(SIE_RX_ERROR)) \
+ goto error; \
+ } \
+ } while (0)
+
+#define WAIT_RX(end) \
do { \
unsigned timeout = 0x200; \
while(!rio8(SIE_RX_PENDING)) { \
@@ -131,7 +142,7 @@ static const char bitstuff_error[] PROGMEM = "RX bitstuff
error\n";
goto timeout; \
if(rio8(SIE_RX_ERROR)) \
goto error; \
- if(!(first) && !rio8(SIE_RX_ACTIVE)) \
+ if(!rio8(SIE_RX_ACTIVE)) \
goto end; \
} \
} while (0)
@@ -143,10 +154,10 @@ static char usb_rx_ack(void)
unsigned char i;
/* SYNC */
- WAIT_RX(1, nothing);
+ WAIT_ACTIVE();
/* PID */
- WAIT_RX(0, nothing);
+ WAIT_RX(nothing);
pid = rio8(SIE_RX_DATA);
/* wait for idle, or simply time out and fall foward */
@@ -160,7 +171,7 @@ static char usb_rx_ack(void)
return 0;
for(i = 200; i; i--)
- WAIT_RX(0,out);
+ WAIT_RX(out);
out:
print_string(ack_error);
print_hex(pid);
@@ -191,10 +202,10 @@ static int usb_in(unsigned addr, unsigned char
expected_data,
usb_tx(in, 3);
/* SYNC */
- WAIT_RX(1, nothing);
+ WAIT_ACTIVE();
/* PID */
- WAIT_RX(0, nothing);
+ WAIT_RX(nothing);
buf[0] = rio8(SIE_RX_DATA);
if(buf[0] == expected_data)
@@ -207,7 +218,7 @@ static int usb_in(unsigned addr, unsigned char
expected_data,
/* unknown packet: try to receive for debug purposes, then dump */
while(len != maxlen) {
- WAIT_RX(0, fail);
+ WAIT_RX(fail);
buf[len++] = rio8(SIE_RX_DATA);
}
fail:
@@ -219,7 +230,7 @@ fail:
ignore:
for(i = 200; i; i--)
- WAIT_RX(0, ignore_eop);
+ WAIT_RX(ignore_eop);
goto complain; /* this doesn't stop - just quit silently */
ignore_eop:
usb_ack();
@@ -231,7 +242,7 @@ complain:
receive:
while(1) {
- WAIT_RX(0, eop);
+ WAIT_RX(eop);
if(len == maxlen)
goto discard;
buf[len++] = rio8(SIE_RX_DATA);
@@ -242,7 +253,7 @@ eop:
discard:
for(i = 200; i; i--)
- WAIT_RX(0, nothing);
+ WAIT_RX(nothing);
nothing:
return 0;
--
1.7.1
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