Configure the timer capture pin to input mode in the timer control

register, in addition to configuring it as input with the pinmux driver.

There was a control register bit commented as "no desc in datasheet".  A
later revision of the manual reveals the bit to be an input/output control
for the timer pin.  In addition to configuring capture or pulse mode, you
apparently have to separately configure the pin direction in the timer
control register.

Before this change, the timer block was apparently driving a signal onto a
pad configured by pinmux as input.  Capture mode still accidentally worked
for me during testing because I was using a very strong signal source that
just out-muscled the weaker drive from the misconfigured pin.

1 files changed, 1 insertions, 1 deletions

diff --git a/sys/arm/ti/am335x/am335x_dmtreg.h b/sys/arm/ti/am335x/am335x_dmtreg.h
index 8a9d63753832..f2ef54ddb917 100644
--- a/sys/arm/ti/am335x/am335x_dmtreg.h
+++ b/sys/arm/ti/am335x/am335x_dmtreg.h
@@ -62,7 +62,7 @@
 #define	  DMT_TCLR_TRGMODE_BOTH	  (2 << 10)	/* Trigger on match + ovflow */
 #define	  DMT_TCLR_PWM_PTOGGLE	  (1 << 12)	/* PWM toggles */
 #define	  DMT_TCLR_CAP_MODE_2ND	  (1 << 13)	/* Capture second event mode */
-#define	  DMT_TCLR_GPO_CFG	  (1 << 14)	/* (no descr in datasheet) */
+#define	  DMT_TCLR_GPO_CFG	  (1 << 14)	/* Tmr pin conf, 0=out, 1=in */
 #define	DMT_TCRR		0x3C		/* Counter Register */
 #define	DMT_TLDR		0x40		/* Load Reg */
 #define	DMT_TTGR		0x44		/* Trigger Reg */