Added some more locking for software copies of register bits that

can be manipulated in interrupt.  Fixed return of -EAGAIN when
external master clock divisor is out of valid range.

diff --git a/comedi/drivers/cb_pcidas64.c b/comedi/drivers/cb_pcidas64.c
index 87efd2142b14250f2d7ff959f0c95c29b079f34e..2e5eefe1d823aabce0fbfa7701a77619d75053c4 100644 (file)
--- a/comedi/drivers/cb_pcidas64.c
+++ b/comedi/drivers/cb_pcidas64.c
@@ -67,8 +67,9 @@ easily added.
 /*
 
 TODO:
-       fix races between interrupt and manipulation of software copies of registers 
        command support for ao
+       to be safe, should add locking for all manipulation of software copies
+               of registers (before adding ao command support)
        user counter subdevice
        there are a number of boards this driver will support when they are
                fully released, but does not yet since the pci device id numbers
@@ -1179,6 +1180,9 @@ static void disable_plx_interrupts( comedi_device *dev )
 static void init_stc_registers( comedi_device *dev )
 {
        uint16_t bits;
+       unsigned long flags;
+
+       comedi_spin_lock_irqsave( &dev->spinlock, flags );
 
        // bit should be set for 6025, although docs say boards with <= 16 chans should be cleared XXX
        if( 1 )
@@ -1194,6 +1198,8 @@ static void init_stc_registers( comedi_device *dev )
        writew(0, priv(dev)->main_iobase + DAQ_SYNC_REG);
        writew(0, priv(dev)->main_iobase + CALIBRATION_REG);
 
+       comedi_spin_unlock_irqrestore( &dev->spinlock, flags );
+
        // set fifos to maximum size
        priv(dev)->fifo_size_bits |= DAC_FIFO_BITS;
        set_ai_fifo_segment_length( dev, board(dev)->ai_fifo->max_segment_length );
@@ -1407,7 +1413,8 @@ static int ai_rinsn(comedi_device *dev,comedi_subdevice *s,comedi_insn *insn,lsa
        unsigned int bits = 0, n, i;
        const int timeout = 100;
        unsigned int channel, range, aref;
-
+       unsigned long flags;
+       
        DEBUG_PRINT("chanspec 0x%x\n", insn->chanspec);
        channel = CR_CHAN(insn->chanspec);
        range = CR_RANGE(insn->chanspec);
@@ -1417,9 +1424,11 @@ static int ai_rinsn(comedi_device *dev,comedi_subdevice *s,comedi_insn *insn,lsa
        // 4020 generates dac done interrupts even though they are disabled
        disable_ai_pacing( dev );
 
+       comedi_spin_lock_irqsave( &dev->spinlock, flags );
        if( insn->chanspec & CR_DITHER )
                priv(dev)->adc_control1_bits |= ADC_DITHER_BIT;
        writew( priv(dev)->adc_control1_bits, priv(dev)->main_iobase + ADC_CONTROL1_REG );
+       comedi_spin_unlock_irqrestore( &dev->spinlock, flags );
 
        if(board(dev)->layout != LAYOUT_4020)
        {
@@ -1579,8 +1588,13 @@ static int ai_config_block_size( comedi_device *dev, lsampl_t *data )
 static int ai_config_master_clock_4020( comedi_device *dev, lsampl_t *data )
 {
        unsigned int divisor = data[4];
+       int retval = 0;
 
-       if( divisor < 2 ) divisor = 2;
+       if( divisor < 2 )
+       {
+               divisor = 2;
+               retval = -EAGAIN;
+       }
 
        switch( data[1] )
        {
@@ -1595,7 +1609,7 @@ static int ai_config_master_clock_4020( comedi_device *dev, lsampl_t *data )
 
        data[4] = divisor;
 
-       return 5;
+       return retval ? retval : 5;
 }
 
 // XXX could add support for 60xx series
@@ -1860,26 +1874,38 @@ static inline unsigned int dma_transfer_size( comedi_device *dev )
 
 static void disable_ai_pacing( comedi_device *dev )
 {
+       unsigned long flags;
+
        disable_ai_interrupts( dev );
 
        /* disable pacing, triggering, etc */
        writew( ADC_DMA_DISABLE_BIT, priv(dev)->main_iobase + ADC_CONTROL0_REG );
+
+       comedi_spin_lock_irqsave( &dev->spinlock, flags );
        priv(dev)->adc_control1_bits |= ADC_QUEUE_CONFIG_BIT;
        writew( priv(dev)->adc_control1_bits, priv(dev)->main_iobase + ADC_CONTROL1_REG );
+       comedi_spin_unlock_irqrestore( &dev->spinlock, flags );
 }
 
 static void disable_ai_interrupts( comedi_device *dev )
 {
+       unsigned long flags;
+
+       comedi_spin_lock_irqsave( &dev->spinlock, flags );
        priv(dev)->intr_enable_bits &=
                ~EN_ADC_INTR_SRC_BIT & ~EN_ADC_DONE_INTR_BIT & ~EN_ADC_ACTIVE_INTR_BIT
                & ~EN_ADC_STOP_INTR_BIT & ~EN_ADC_OVERRUN_BIT & ~ADC_INTR_SRC_MASK;
        writew( priv(dev)->intr_enable_bits, priv(dev)->main_iobase + INTR_ENABLE_REG );
+       comedi_spin_unlock_irqrestore( &dev->spinlock, flags );
+
        DEBUG_PRINT( "intr enable bits 0x%x\n", priv(dev)->intr_enable_bits );
 }
 
 static void enable_ai_interrupts( comedi_device *dev, const comedi_cmd *cmd )
 {
        uint32_t bits;
+       unsigned long flags;
+
 
        bits = EN_ADC_OVERRUN_BIT | EN_ADC_DONE_INTR_BIT |
                EN_ADC_ACTIVE_INTR_BIT | EN_ADC_STOP_INTR_BIT;
@@ -1890,9 +1916,11 @@ static void enable_ai_interrupts( comedi_device *dev, const comedi_cmd *cmd )
                if( board(dev)->layout != LAYOUT_4020 )
                        bits |= ADC_INTR_EOSCAN_BITS | EN_ADC_INTR_SRC_BIT;
        }
+       comedi_spin_lock_irqsave( &dev->spinlock, flags );
        priv(dev)->intr_enable_bits |= bits;
        writew( priv(dev)->intr_enable_bits, priv(dev)->main_iobase + INTR_ENABLE_REG );
        DEBUG_PRINT( "intr enable bits 0x%x\n", priv(dev)->intr_enable_bits );
+       comedi_spin_unlock_irqrestore( &dev->spinlock, flags );
 }
 
 static uint32_t ai_convert_counter_6xxx( const comedi_device *dev, const comedi_cmd *cmd )
@@ -2110,9 +2138,11 @@ static int ai_cmd(comedi_device *dev,comedi_subdevice *s)
                bits |= adc_lo_chan_4020_bits( CR_CHAN( cmd->chanlist[0] ) );
                bits |= adc_hi_chan_4020_bits( CR_CHAN( cmd->chanlist[ cmd->chanlist_len - 1 ] ) );
        }
+       comedi_spin_lock_irqsave( &dev->spinlock, flags );
        priv(dev)->adc_control1_bits |= bits;
        writew( priv(dev)->adc_control1_bits, priv(dev)->main_iobase + ADC_CONTROL1_REG );
        DEBUG_PRINT("control1 bits 0x%x\n", priv(dev)->adc_control1_bits);
+       comedi_spin_unlock_irqrestore( &dev->spinlock, flags );
 
        abort_dma(dev, 1);
        if((cmd->flags & TRIG_WAKE_EOS) == 0 ||