staging: comedi : Analog input trigerring modes for cb_pcidas

This patch allows the possibility to choose between edgre triggering
and level trigerring, for the analog input, on the Measurement
Computing PCI-DAS* boards

Signed-off-by: Brice Dubost <braice@braice.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/staging/comedi/drivers/cb_pcidas.c b/drivers/staging/comedi/drivers/cb_pcidas.c
index 3275fc50615f7c8851a0bb33ed6fe6833c95ba8f..0941643b3869df3d3de1969a01a97264cd95d7f4 100644 (file)
--- a/drivers/staging/comedi/drivers/cb_pcidas.c
+++ b/drivers/staging/comedi/drivers/cb_pcidas.c
@@ -53,6 +53,15 @@ Configuration options:
 For commands, the scanned channels must be consecutive
 (i.e. 4-5-6-7, 2-3-4,...), and must all have the same
 range and aref.
+
+AI Triggering:
+   For start_src == TRIG_EXT, the A/D EXTERNAL TRIGGER IN (pin 45) is used.
+   For 1602 series, the start_arg is interpreted as follows:
+     start_arg == 0                   => gated triger (level high)
+     start_arg == CR_INVERT           => gated triger (level low)
+     start_arg == CR_EDGE             => Rising edge
+     start_arg == CR_EDGE | CR_INVERT => Falling edge
+   For the other boards the trigger will be done on rising edge
 */
 /*
 
@@ -135,6 +144,8 @@ analog triggering on 1602 series
 #define   EXT_TRIGGER 0x2      /*  external start trigger */
 #define   ANALOG_TRIGGER 0x3   /*  external analog trigger */
 #define   TRIGGER_MASK 0x3     /*  mask of bits that determine start trigger */
+#define   TGPOL        0x04            /*  invert the edge/level of the external trigger (1602 only) */
+#define   TGSEL        0x08            /*  if set edge triggered, otherwise level trigerred (1602 only) */
 #define   TGEN 0x10            /*  enable external start trigger */
 #define   BURSTE 0x20          /*  burst mode enable */
 #define   XTRCL        0x80            /*  clear external trigger */
@@ -257,6 +268,8 @@ struct cb_pcidas_board {
        const struct comedi_lrange *ranges;
        enum trimpot_model trimpot;
        unsigned has_dac08:1;
+       unsigned has_ai_trig_gated:1;   /* Tells if the AI trigger can be gated */
+       unsigned has_ai_trig_invert:1;  /* Tells if the AI trigger can be inverted */
 };
 
 static const struct cb_pcidas_board cb_pcidas_boards[] = {
@@ -274,6 +287,8 @@ static const struct cb_pcidas_board cb_pcidas_boards[] = {
         .ranges = &cb_pcidas_ranges,
         .trimpot = AD8402,
         .has_dac08 = 1,
+        .has_ai_trig_gated = 1,
+        .has_ai_trig_invert = 1,
         },
        {
         .name = "pci-das1200",
@@ -288,6 +303,8 @@ static const struct cb_pcidas_board cb_pcidas_boards[] = {
         .ranges = &cb_pcidas_ranges,
         .trimpot = AD7376,
         .has_dac08 = 0,
+        .has_ai_trig_gated = 0,
+        .has_ai_trig_invert = 0,
         },
        {
         .name = "pci-das1602/12",
@@ -303,6 +320,8 @@ static const struct cb_pcidas_board cb_pcidas_boards[] = {
         .ranges = &cb_pcidas_ranges,
         .trimpot = AD7376,
         .has_dac08 = 0,
+        .has_ai_trig_gated = 1,
+        .has_ai_trig_invert = 1,
         },
        {
         .name = "pci-das1200/jr",
@@ -317,6 +336,8 @@ static const struct cb_pcidas_board cb_pcidas_boards[] = {
         .ranges = &cb_pcidas_ranges,
         .trimpot = AD7376,
         .has_dac08 = 0,
+        .has_ai_trig_gated = 0,
+        .has_ai_trig_invert = 0,
         },
        {
         .name = "pci-das1602/16/jr",
@@ -331,6 +352,8 @@ static const struct cb_pcidas_board cb_pcidas_boards[] = {
         .ranges = &cb_pcidas_ranges,
         .trimpot = AD8402,
         .has_dac08 = 1,
+        .has_ai_trig_gated = 1,
+        .has_ai_trig_invert = 1,
         },
        {
         .name = "pci-das1000",
@@ -345,6 +368,8 @@ static const struct cb_pcidas_board cb_pcidas_boards[] = {
         .ranges = &cb_pcidas_ranges,
         .trimpot = AD7376,
         .has_dac08 = 0,
+        .has_ai_trig_gated = 0,
+        .has_ai_trig_invert = 0,
         },
        {
         .name = "pci-das1001",
@@ -359,6 +384,8 @@ static const struct cb_pcidas_board cb_pcidas_boards[] = {
         .ranges = &cb_pcidas_alt_ranges,
         .trimpot = AD7376,
         .has_dac08 = 0,
+        .has_ai_trig_gated = 0,
+        .has_ai_trig_invert = 0,
         },
        {
         .name = "pci-das1002",
@@ -373,6 +400,8 @@ static const struct cb_pcidas_board cb_pcidas_boards[] = {
         .ranges = &cb_pcidas_ranges,
         .trimpot = AD7376,
         .has_dac08 = 0,
+        .has_ai_trig_gated = 0,
+        .has_ai_trig_invert = 0,
         },
 };
 
@@ -1113,9 +1142,27 @@ static int cb_pcidas_ai_cmdtest(struct comedi_device *dev,
 
        /* step 3: make sure arguments are trivially compatible */
 
-       if (cmd->start_arg != 0) {
-               cmd->start_arg = 0;
-               err++;
+       switch (cmd->start_src) {
+       case TRIG_EXT:
+               /* External trigger, only CR_EDGE and CR_INVERT flags allowed */
+               if ((cmd->start_arg
+                    & (CR_FLAGS_MASK & ~(CR_EDGE | CR_INVERT))) != 0) {
+                       cmd->start_arg &=
+                           ~(CR_FLAGS_MASK & ~(CR_EDGE | CR_INVERT));
+                       err++;
+               }
+               if (!thisboard->has_ai_trig_invert &&
+                   (cmd->start_arg & CR_INVERT)) {
+                       cmd->start_arg &= (CR_FLAGS_MASK & ~CR_INVERT);
+                       err++;
+               }
+               break;
+       default:
+               if (cmd->start_arg != 0) {
+                       cmd->start_arg = 0;
+                       err++;
+               }
+               break;
        }
 
        if (cmd->scan_begin_src == TRIG_TIMER) {
@@ -1270,9 +1317,14 @@ static int cb_pcidas_ai_cmd(struct comedi_device *dev,
        bits = 0;
        if (cmd->start_src == TRIG_NOW)
                bits |= SW_TRIGGER;
-       else if (cmd->start_src == TRIG_EXT)
+       else if (cmd->start_src == TRIG_EXT) {
                bits |= EXT_TRIGGER | TGEN | XTRCL;
-       else {
+               if (thisboard->has_ai_trig_invert
+                   && (cmd->start_arg & CR_INVERT))
+                       bits |= TGPOL;
+               if (thisboard->has_ai_trig_gated && (cmd->start_arg & CR_EDGE))
+                       bits |= TGSEL;
+       } else {
                comedi_error(dev, "bug!");
                return -1;
        }