From adf02ac1ef47f4eb053377cc6b863be17b00e08d Mon Sep 17 00:00:00 2001
From: Frank Mori Hess <fmhess@speakeasy.net>
Date: Tue, 7 May 2002 23:24:25 +0000
Subject: [PATCH] added config insn for choosing rising or falling edge trigger

---
 Documentation/comedi/insn_config |  8 ++++--
 comedi/drivers/cb_pcidas64.c     | 43 ++++++++++++++++++++++++++++----
 include/linux/comedi.h           |  3 +++
 3 files changed, 47 insertions(+), 7 deletions(-)

diff --git a/Documentation/comedi/insn_config b/Documentation/comedi/insn_config
index 3edd2894..c2b3eb04 100644
--- a/Documentation/comedi/insn_config
+++ b/Documentation/comedi/insn_config
@@ -24,7 +24,7 @@ Notes:
     that are tied to start_src, convert_src, etc.?
 
 
-ID=xxx: extended digital triggering
+ID=INSN_CONFIG_DIGITAL_TRIG: extended digital triggering
 
   length =
   chanspec: ignored
@@ -35,7 +35,11 @@ ID=xxx: extended digital triggering
           trigger
 
   Notes:
-    - should this be the same as triggering for counter/timers?
+
+	should this be the same as triggering for counter/timers?
+    
+	flags are:
+		DIGITAL_TRIG_RISING: trigger on rising edge (or falling edge if not set)
 
 
 ID=xxx: counter configuration
diff --git a/comedi/drivers/cb_pcidas64.c b/comedi/drivers/cb_pcidas64.c
index c7a2b0dc..72529ceb 100644
--- a/comedi/drivers/cb_pcidas64.c
+++ b/comedi/drivers/cb_pcidas64.c
@@ -676,6 +676,7 @@ typedef struct
 	volatile uint32_t plx_intcsr_bits;	// last bits written to plx interrupt control and status register
 	volatile int calibration_source;	// index of calibration source readable through ai ch0
 	volatile uint8_t i2c_cal_range_bits;	// bits written to i2c calibration/range register
+	volatile unsigned int ext_trig_falling;	// configure digital triggers to trigger on falling edge
 	// states of various devices stored to enable read-back
 	unsigned int ad8402_state[2];
 	unsigned int dac8800_state[8];
@@ -1323,13 +1324,10 @@ static int ai_rinsn(comedi_device *dev,comedi_subdevice *s,comedi_insn *insn,lsa
 	return n;
 }
 
-static int ai_config_insn(comedi_device *dev,comedi_subdevice *s,comedi_insn *insn,lsampl_t *data)
+static int ai_config_calibration_source( comedi_device *dev, lsampl_t *data )
 {
-	int id = data[0];
-	int source = data[1];
 	static const int num_calibration_sources = 8;
-
-	if(id != INSN_CONFIG_ALT_SOURCE) return -EINVAL;
+	lsampl_t source = data[1];
 
 	if(source >= num_calibration_sources)
 		return -EINVAL;
@@ -1340,6 +1338,39 @@ static int ai_config_insn(comedi_device *dev,comedi_subdevice *s,comedi_insn *in
 	return 1;
 }
 
+static int ai_config_digital_trigger( comedi_device *dev, lsampl_t *data )
+{
+	lsampl_t flags = data[1];
+
+	if( flags & DIGITAL_TRIG_RISING)
+	{
+		private(dev)->ext_trig_falling = 0;
+	}else
+	{
+		private(dev)->ext_trig_falling = 1;
+	}
+	
+	return 1;
+}
+
+static int ai_config_insn( comedi_device *dev, comedi_subdevice *s, comedi_insn *insn, lsampl_t *data)
+{
+	int id = data[0];
+
+	switch( id )
+	{
+		case INSN_CONFIG_ALT_SOURCE:
+			ai_config_calibration_source( dev, data );
+			break;
+		case INSN_CONFIG_DIGITAL_TRIG:
+			ai_config_digital_trigger( dev, data );
+		default:
+			return -EINVAL;
+			break;
+	}
+	return -EINVAL;
+}
+
 static int ai_cmdtest(comedi_device *dev,comedi_subdevice *s, comedi_cmd *cmd)
 {	int err = 0;
 	int tmp;
@@ -1687,6 +1718,8 @@ static int ai_cmd(comedi_device *dev,comedi_subdevice *s)
 		bits |= ADC_START_TRIG_EXT_BITS;
 	else if(cmd->start_src == TRIG_NOW)
 		bits |= ADC_START_TRIG_SOFT_BITS;
+	if( private(dev)->ext_trig_falling )
+		bits |= ADC_START_TRIG_FALLING_BIT;
 	writew(bits, private(dev)->main_iobase + ADC_CONTROL0_REG);
 	DEBUG_PRINT("control0 bits 0x%x\n", bits);
 
diff --git a/include/linux/comedi.h b/include/linux/comedi.h
index d1a82670..f9d84035 100644
--- a/include/linux/comedi.h
+++ b/include/linux/comedi.h
@@ -214,6 +214,9 @@ typedef unsigned short sampl_t;
 //#define INSN_CONFIG_TRIG		0x12
 //#define INSN_CONFIG_COUNTER		0x13
 #define INSN_CONFIG_ALT_SOURCE		0x14
+#define INSN_CONFIG_DIGITAL_TRIG		0x15
+// flags for INSN_CONFIG_DIGITAL_TRIG
+#define  DIGITAL_TRIG_RISING	0x1
 
 /* ioctls */
 
-- 
2.26.2