From: Keith Packard <keithp@keithp.com>
Date: Mon, 15 Oct 2012 01:50:45 +0000 (-0700)
Subject: altos: Wait for companion to see CS before attempting communcation
X-Git-Url: https://git.gag.com/?p=fw%2Faltos;a=commitdiff_plain;h=refs%2Fheads%2Fcompanion-delay

altos: Wait for companion to see CS before attempting communcation

The AVR just can't go fast enough to see the CS in time, so pause for
a while.

(rewritten from f9607fb76c22187396cceb46b745fa1485d4f155)

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

diff --git a/src/drivers/ao_companion.c b/src/drivers/ao_companion.c
index c749adea..2ed407f1 100644
--- a/src/drivers/ao_companion.c
+++ b/src/drivers/ao_companion.c
@@ -24,11 +24,14 @@
 #endif
 
 #define COMPANION_SELECT()	do {			\
+		uint8_t	pause;				\
 		ao_spi_get_bit(AO_COMPANION_CS_PORT,	\
 			       AO_COMPANION_CS_PIN,	\
 			       AO_COMPANION_CS,		\
 			       AO_COMPANION_SPI_BUS,	\
 			       AO_SPI_SPEED_200kHz);	\
+		for (pause = 0; pause < 100; pause++)	\
+			ao_arch_nop();			\
 	} while (0)
 
 #define COMPANION_DESELECT()	do {			\