altos: Do not release interrupts from any pollchar function

getchar relies on interrupts being blocked across the pollchar calls
and into the sleep call or it may go to sleep with data pending.

This prefixes all pollchar functions with _ to indicate that they are
to be called with interrupts blocked and eliminates all interrupt
manipulation calls from within the pollchar functions.

Signed-off-by: Keith Packard <keithp@keithp.com>

1 files changed, 17 insertions, 25 deletions

diff --git a/src/avr/ao_usb_avr.c b/src/avr/ao_usb_avr.c
index 2ef546c9..bd75b17d 100644
--- a/src/avr/ao_usb_avr.c
+++ b/src/avr/ao_usb_avr.c
@@ -411,7 +411,7 @@ ao_usb_ep0(void)
 
 /* Wait for a free IN buffer */
 static void
-ao_usb_in_wait(void)
+_ao_usb_in_wait(void)
 {
 	for (;;) {
 		/* Check if the current buffer is writable */
@@ -419,7 +419,6 @@ ao_usb_in_wait(void)
 		if (UEINTX & (1 << RWAL))
 			break;
 
-		cli();
 		/* Wait for an IN buffer to be ready */
 		for (;;) {
 			UENUM = AO_USB_IN_EP;
@@ -430,24 +429,24 @@ ao_usb_in_wait(void)
 		}
 		/* Ack the interrupt */
 		UEINTX &= ~(1 << TXINI);
-		sei();
 	}
 }
 
 /* Queue the current IN buffer for transmission */
 static void
-ao_usb_in_send(void)
+_ao_usb_in_send(void)
 {
 	UENUM = AO_USB_IN_EP;
 	UEINTX &= ~(1 << FIFOCON);
 }
 
 void
-ao_usb_flush(void) __critical
+ao_usb_flush(void)
 {
 	if (!ao_usb_running)
 		return;
 
+	ao_arch_block_interrupts();
 	/* Anytime we've sent a character since
 	 * the last time we flushed, we'll need
 	 * to send a packet -- the only other time
@@ -457,18 +456,20 @@ ao_usb_flush(void) __critical
 	 */
 	if (!ao_usb_in_flushed) {
 		ao_usb_in_flushed = 1;
-		ao_usb_in_wait();
-		ao_usb_in_send();
+		_ao_usb_in_wait();
+		_ao_usb_in_send();
 	}
+	ao_arch_release_interrupts();
 }
 
 void
-ao_usb_putchar(char c) __critical __reentrant
+ao_usb_putchar(char c)
 {
 	if (!ao_usb_running)
 		return;
 
-	ao_usb_in_wait();
+	ao_arch_block_interrupts();
+	_ao_usb_in_wait();
 
 	/* Queue a byte */
 	UENUM = AO_USB_IN_EP;
@@ -476,11 +477,12 @@ ao_usb_putchar(char c) __critical __reentrant
 
 	/* Send the packet when full */
 	if ((UEINTX & (1 << RWAL)) == 0)
-		ao_usb_in_send();
+		_ao_usb_in_send();
 	ao_usb_in_flushed = 0;
+	ao_arch_release_interrupts();
 }
 
-static int
+int
 _ao_usb_pollchar(void)
 {
 	uint8_t c;
@@ -517,25 +519,15 @@ _ao_usb_pollchar(void)
 	return c;
 }
 
-int
-ao_usb_pollchar(void)
-{
-	int	c;
-	cli();
-	c = _ao_usb_pollchar();
-	sei();
-	return c;
-}
-
 char
-ao_usb_getchar(void) __critical
+ao_usb_getchar(void)
 {
 	int	c;
 
-	cli();
+	ao_arch_block_interrupts();
 	while ((c = _ao_usb_pollchar()) == AO_READ_AGAIN)
 		ao_sleep(&ao_stdin_ready);
-	sei();
+	ao_arch_release_interrupts();
 	return c;
 }
 
@@ -668,5 +660,5 @@ ao_usb_init(void)
 #if USB_DEBUG
 	ao_add_task(&ao_usb_echo_task, ao_usb_echo, "usb echo");
 #endif
-	ao_add_stdio(ao_usb_pollchar, ao_usb_putchar, ao_usb_flush);
+	ao_add_stdio(_ao_usb_pollchar, ao_usb_putchar, ao_usb_flush);
 }