initialize caldacs to middle-of-range during attach, don't bother

reprogramming them if they are already set as desired

diff --git a/comedi/drivers/cb_pcidas64.c b/comedi/drivers/cb_pcidas64.c
index 67170c4af9fba6d4b014e7b314b36d63473caaec..024eb96c95238e6469518b1c7202c4aa50d7acf7 100644 (file)
--- a/comedi/drivers/cb_pcidas64.c
+++ b/comedi/drivers/cb_pcidas64.c
@@ -908,11 +908,13 @@ static int dio_60xx_wbits(comedi_device *dev, comedi_subdevice *s, comedi_insn *
 static int calib_read_insn(comedi_device *dev, comedi_subdevice *s, comedi_insn *insn, lsampl_t *data);
 static int calib_write_insn(comedi_device *dev, comedi_subdevice *s, comedi_insn *insn, lsampl_t *data);
 static int ad8402_read_insn(comedi_device *dev, comedi_subdevice *s, comedi_insn *insn, lsampl_t *data);
+static void ad8402_write( comedi_device *dev, unsigned int channel, unsigned int value );
 static int ad8402_write_insn(comedi_device *dev, comedi_subdevice *s, comedi_insn *insn, lsampl_t *data);
 static int eeprom_read_insn(comedi_device *dev, comedi_subdevice *s, comedi_insn *insn, lsampl_t *data);
 static void check_adc_timing(comedi_cmd *cmd);
 static unsigned int get_divisor(unsigned int ns, unsigned int flags);
 static void i2c_write(comedi_device *dev, unsigned int address, const uint8_t *data, unsigned int length);
+static void caldac_write( comedi_device *dev, unsigned int channel, unsigned int value );
 static int caldac_8800_write(comedi_device *dev, unsigned int address, uint8_t value);
 //static int dac_1590_write(comedi_device *dev, unsigned int dac_a, unsigned int dac_b);
 static int caldac_i2c_write(comedi_device *dev, unsigned int caldac_channel, unsigned int value);
@@ -1006,6 +1008,7 @@ static int setup_subdevices(comedi_device *dev)
 {
        comedi_subdevice *s;
        unsigned long dio_8255_iobase;
+       int i;
 
        if( alloc_subdevices( dev, 10 ) < 0 )
                return -ENOMEM;
@@ -1128,6 +1131,8 @@ static int setup_subdevices(comedi_device *dev)
                s->maxdata = 0xff;
        s->insn_read = calib_read_insn;
        s->insn_write = calib_write_insn;
+       for( i = 0; i < s->n_chan; i++ )
+               caldac_write( dev, i, s->maxdata / 2 );
 
        // 2 channel ad8402 potentiometer
        s = dev->subdevices + 7;
@@ -1139,6 +1144,8 @@ static int setup_subdevices(comedi_device *dev)
                s->insn_read = ad8402_read_insn;
                s->insn_write = ad8402_write_insn;
                s->maxdata = 0xff;
+               for( i = 0; i < s->n_chan; i++ )
+                       ad8402_write( dev, i, s->maxdata / 2 );
        } else
                s->type = COMEDI_SUBD_UNUSED;
 
@@ -2610,24 +2617,34 @@ static int dio_60xx_wbits(comedi_device *dev, comedi_subdevice *s, comedi_insn *
        return 2;
 }
 
-static int calib_write_insn(comedi_device *dev, comedi_subdevice *s, comedi_insn *insn, lsampl_t *data)
+static void caldac_write( comedi_device *dev, unsigned int channel, unsigned int value )
 {
-       int channel = CR_CHAN(insn->chanspec);
-
-       priv(dev)->caldac_state[channel] = data[0];
+       priv(dev)->caldac_state[channel] = value;
 
        switch(board(dev)->layout)
        {
                case LAYOUT_60XX:
                case LAYOUT_64XX:
-                       caldac_8800_write(dev, channel, data[0]);
+                       caldac_8800_write(dev, channel, value);
                        break;
                case LAYOUT_4020:
-                       caldac_i2c_write(dev, channel, data[0]);
+                       caldac_i2c_write(dev, channel, value);
                        break;
                default:
                        break;
        }
+}
+
+static int calib_write_insn(comedi_device *dev, comedi_subdevice *s, comedi_insn *insn, lsampl_t *data)
+{
+       int channel = CR_CHAN(insn->chanspec);
+
+       /* return immediately if setting hasn't changed, since
+        * programming these things is slow */
+       if( priv(dev)->caldac_state[channel] == data[0] )
+               return 1;
+
+       caldac_write( dev, channel, data[0] );
 
        return 1;
 }
@@ -2636,40 +2653,53 @@ static int calib_read_insn(comedi_device *dev, comedi_subdevice *s, comedi_insn
 {
        unsigned int channel = CR_CHAN(insn->chanspec);
 
-        data[0] = priv(dev)->caldac_state[channel];
+       data[0] = priv(dev)->caldac_state[channel];
 
-        return 1;
+       return 1;
 }
 
-/* for pci-das6402/16, channel 0 is analog input gain and channel 1 is offset */
-static int ad8402_write_insn(comedi_device *dev, comedi_subdevice *s, comedi_insn *insn, lsampl_t *data)
+static void ad8402_write( comedi_device *dev, unsigned int channel, unsigned int value )
 {
        static const int bitstream_length = 10;
-       int channel = CR_CHAN(insn->chanspec);
-       unsigned int bitstream = ((channel & 0x3) << 8) | (data[0] & 0xff);
        unsigned int bit, register_bits;
+       unsigned int bitstream = ( ( channel & 0x3 ) << 8 ) | ( value & 0xff );
        static const int ad8402_udelay = 1;
 
-       priv(dev)->ad8402_state[channel] = data[0];
+       priv(dev)->ad8402_state[ channel ] = value;
 
        register_bits = SELECT_8402_64XX_BIT;
-       udelay(ad8402_udelay);
-       writew(register_bits, priv(dev)->main_iobase + CALIBRATION_REG);
+       udelay( ad8402_udelay );
+       writew( register_bits, priv(dev)->main_iobase + CALIBRATION_REG );
 
-       for(bit = 1 << (bitstream_length - 1); bit; bit >>= 1)
+       for( bit = 1 << ( bitstream_length - 1 ); bit; bit >>= 1 )
        {
-               if(bitstream & bit)
+               if( bitstream & bit )
                        register_bits |= SERIAL_DATA_IN_BIT;
                else
                        register_bits &= ~SERIAL_DATA_IN_BIT;
-               udelay(ad8402_udelay);
-               writew(register_bits, priv(dev)->main_iobase + CALIBRATION_REG);
-               udelay(ad8402_udelay);
-               writew(register_bits | SERIAL_CLOCK_BIT, priv(dev)->main_iobase + CALIBRATION_REG);
-        }
+               udelay( ad8402_udelay );
+               writew( register_bits, priv(dev)->main_iobase + CALIBRATION_REG );
+               udelay( ad8402_udelay );
+               writew( register_bits | SERIAL_CLOCK_BIT, priv(dev)->main_iobase + CALIBRATION_REG );
+       }
 
-       udelay(ad8402_udelay);
-       writew(0, priv(dev)->main_iobase + CALIBRATION_REG);
+       udelay( ad8402_udelay );
+       writew( 0, priv(dev)->main_iobase + CALIBRATION_REG );
+}
+
+/* for pci-das6402/16, channel 0 is analog input gain and channel 1 is offset */
+static int ad8402_write_insn(comedi_device *dev, comedi_subdevice *s, comedi_insn *insn, lsampl_t *data)
+{
+       int channel = CR_CHAN(insn->chanspec);
+
+       /* return immediately if setting hasn't changed, since
+        * programming these things is slow */
+       if( priv(dev)->ad8402_state[channel] == data[0] )
+               return 1;
+
+       priv(dev)->ad8402_state[channel] = data[0];
+
+       ad8402_write( dev, channel, data[ 0 ] );
 
        return 1;
 }