staging: comedi: s526: refactor gpct registers

The S526 board has 4 general purpose counter/timers. The current
defines used for the registers of these devices do not provide much
clarity in what they are.

Refactor the code to add some clarity.

Replace the current register defines with macros that return the
correct offset based on the counter 'channel'. Introduce a some helper
functions to handle reading/writing the LSB/MSB registers so that
they are always accessed in the correct oreder.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/comedi/drivers/s526.c b/drivers/staging/comedi/drivers/s526.c
index 817ce15..c011c70 100644 (file)
--- a/drivers/staging/comedi/drivers/s526.c
+++ b/drivers/staging/comedi/drivers/s526.c
@@ -55,22 +55,12 @@
 #define REG_IER 0x0C
 #define REG_ISR 0x0E
 #define REG_MSC 0x10
-#define REG_C0L 0x12
-#define REG_C0H 0x14
-#define REG_C0M 0x16
-#define REG_C0C 0x18
-#define REG_C1L 0x1A
-#define REG_C1H 0x1C
-#define REG_C1M 0x1E
-#define REG_C1C 0x20
-#define REG_C2L 0x22
-#define REG_C2H 0x24
-#define REG_C2M 0x26
-#define REG_C2C 0x28
-#define REG_C3L 0x2A
-#define REG_C3H 0x2C
-#define REG_C3M 0x2E
-#define REG_C3C 0x30
+
+#define S526_GPCT_LSB_REG(x)   (0x12 + ((x) * 8))
+#define S526_GPCT_MSB_REG(x)   (0x14 + ((x) * 8))
+#define S526_GPCT_MODE_REG(x)  (0x16 + ((x) * 8))
+#define S526_GPCT_CTRL_REG(x)  (0x18 + ((x) * 8))
+
 #define REG_EED 0x32
 #define REG_EEC 0x34
 
@@ -114,24 +104,36 @@ struct s526_private {
        unsigned short ai_config;
 };
 
+static void s526_gpct_write(struct comedi_device *dev,
+                           unsigned int chan, unsigned int val)
+{
+       /* write high word then low word */
+       outw((val >> 16) & 0xffff, dev->iobase + S526_GPCT_MSB_REG(chan));
+       outw(val & 0xffff, dev->iobase + S526_GPCT_LSB_REG(chan));
+}
+
+static unsigned int s526_gpct_read(struct comedi_device *dev,
+                                  unsigned int chan)
+{
+       unsigned int val;
+
+       /* read the low word then high word */
+       val = inw(dev->iobase + S526_GPCT_LSB_REG(chan)) & 0xffff;
+       val |= (inw(dev->iobase + S526_GPCT_MSB_REG(chan)) & 0xff) << 16;
+
+       return val;
+}
+
 static int s526_gpct_rinsn(struct comedi_device *dev,
                           struct comedi_subdevice *s,
                           struct comedi_insn *insn,
                           unsigned int *data)
 {
        unsigned int chan = CR_CHAN(insn->chanspec);
-       unsigned long chan_iobase = dev->iobase + chan * 8;
-       unsigned int lo;
-       unsigned int hi;
        int i;
 
-       for (i = 0; i < insn->n; i++) {
-               /* Read the low word first */
-               lo = inw(chan_iobase + REG_C0L) & 0xffff;
-               hi = inw(chan_iobase + REG_C0H) & 0xff;
-
-               data[i] = (hi << 16) | lo;
-       }
+       for (i = 0; i < insn->n; i++)
+               data[i] = s526_gpct_read(dev, chan);
 
        return insn->n;
 }
@@ -143,7 +145,6 @@ static int s526_gpct_insn_config(struct comedi_device *dev,
 {
        struct s526_private *devpriv = dev->private;
        unsigned int chan = CR_CHAN(insn->chanspec);
-       unsigned long chan_iobase = dev->iobase + chan * 8;
        unsigned int val;
        union cmReg cmReg;
 
@@ -174,32 +175,31 @@ static int s526_gpct_insn_config(struct comedi_device *dev,
                cmReg.reg.preloadRegSel = 0;    /*  PR0 */
                cmReg.reg.reserved = 0;
 
-               outw(cmReg.value, chan_iobase + REG_C0M);
+               outw(cmReg.value, dev->iobase + S526_GPCT_MODE_REG(chan));
 
-               outw(0x0001, chan_iobase + REG_C0H);
-               outw(0x3C68, chan_iobase + REG_C0L);
+               s526_gpct_write(dev, chan, 0x0013c68);
 
                /*  Reset the counter */
-               outw(0x8000, chan_iobase + REG_C0C);
+               outw(0x8000, dev->iobase + S526_GPCT_CTRL_REG(chan));
                /*  Load the counter from PR0 */
-               outw(0x4000, chan_iobase + REG_C0C);
+               outw(0x4000, dev->iobase + S526_GPCT_CTRL_REG(chan));
 
                /*  Reset RCAP (fires one-shot) */
-               outw(0x0008, chan_iobase + REG_C0C);
+               outw(0x0008, dev->iobase + S526_GPCT_CTRL_REG(chan));
 
 #endif
 
 #if 1
                /*  Set Counter Mode Register */
                cmReg.value = data[1] & 0xffff;
-               outw(cmReg.value, chan_iobase + REG_C0M);
+               outw(cmReg.value, dev->iobase + S526_GPCT_MODE_REG(chan));
 
                /*  Reset the counter if it is software preload */
                if (cmReg.reg.autoLoadResetRcap == 0) {
                        /*  Reset the counter */
-                       outw(0x8000, chan_iobase + REG_C0C);
+                       outw(0x8000, dev->iobase + S526_GPCT_CTRL_REG(chan));
                        /* Load the counter from PR0
-                        * outw(0x4000, chan_iobase + REG_C0C);
+                        * outw(0x4000, dev->iobase + S526_GPCT_CTRL_REG(chan));
                         */
                }
 #else
@@ -227,27 +227,22 @@ static int s526_gpct_insn_config(struct comedi_device *dev,
 
                /*  Set Counter Mode Register */
                cmReg.value = data[1] & 0xffff;
-               outw(cmReg.value, chan_iobase + REG_C0M);
+               outw(cmReg.value, dev->iobase + S526_GPCT_MODE_REG(chan));
 
-               /*  Load the pre-load register high word */
-               val = (data[2] >> 16) & 0xffff;
-               outw(val, chan_iobase + REG_C0H);
-
-               /*  Load the pre-load register low word */
-               val = data[2] & 0xffff;
-               outw(val, chan_iobase + REG_C0L);
+               /*  Load the pre-load register */
+               s526_gpct_write(dev, chan, data[2]);
 
                /*  Write the Counter Control Register */
-               if (data[3]) {
-                       val = data[3] & 0xffff;
-                       outw(val, chan_iobase + REG_C0C);
-               }
+               if (data[3])
+                       outw(data[3] & 0xffff,
+                            dev->iobase + S526_GPCT_CTRL_REG(chan));
+
                /*  Reset the counter if it is software preload */
                if (cmReg.reg.autoLoadResetRcap == 0) {
                        /*  Reset the counter */
-                       outw(0x8000, chan_iobase + REG_C0C);
+                       outw(0x8000, dev->iobase + S526_GPCT_CTRL_REG(chan));
                        /*  Load the counter from PR0 */
-                       outw(0x4000, chan_iobase + REG_C0C);
+                       outw(0x4000, dev->iobase + S526_GPCT_CTRL_REG(chan));
                }
 #endif
                break;
@@ -265,33 +260,23 @@ static int s526_gpct_insn_config(struct comedi_device *dev,
                /*  Set Counter Mode Register */
                cmReg.value = data[1] & 0xffff;
                cmReg.reg.preloadRegSel = 0;    /*  PR0 */
-               outw(cmReg.value, chan_iobase + REG_C0M);
-
-               /*  Load the pre-load register 0 high word */
-               val = (data[2] >> 16) & 0xffff;
-               outw(val, chan_iobase + REG_C0H);
+               outw(cmReg.value, dev->iobase + S526_GPCT_MODE_REG(chan));
 
-               /*  Load the pre-load register 0 low word */
-               val = data[2] & 0xffff;
-               outw(val, chan_iobase + REG_C0L);
+               /* Load the pre-load register 0 */
+               s526_gpct_write(dev, chan, data[2]);
 
                /*  Set Counter Mode Register */
                cmReg.value = data[1] & 0xffff;
                cmReg.reg.preloadRegSel = 1;    /*  PR1 */
-               outw(cmReg.value, chan_iobase + REG_C0M);
-
-               /*  Load the pre-load register 1 high word */
-               val = (data[3] >> 16) & 0xffff;
-               outw(val, chan_iobase + REG_C0H);
+               outw(cmReg.value, dev->iobase + S526_GPCT_MODE_REG(chan));
 
-               /*  Load the pre-load register 1 low word */
-               val = data[3] & 0xffff;
-               outw(val, chan_iobase + REG_C0L);
+               /* Load the pre-load register 1 */
+               s526_gpct_write(dev, chan, data[3]);
 
                /*  Write the Counter Control Register */
                if (data[4]) {
                        val = data[4] & 0xffff;
-                       outw(val, chan_iobase + REG_C0C);
+                       outw(val, dev->iobase + S526_GPCT_CTRL_REG(chan));
                }
                break;
 
@@ -308,33 +293,23 @@ static int s526_gpct_insn_config(struct comedi_device *dev,
                /*  Set Counter Mode Register */
                cmReg.value = data[1] & 0xffff;
                cmReg.reg.preloadRegSel = 0;    /*  PR0 */
-               outw(cmReg.value, chan_iobase + REG_C0M);
+               outw(cmReg.value, dev->iobase + S526_GPCT_MODE_REG(chan));
 
-               /*  Load the pre-load register 0 high word */
-               val = (data[2] >> 16) & 0xffff;
-               outw(val, chan_iobase + REG_C0H);
-
-               /*  Load the pre-load register 0 low word */
-               val = data[2] & 0xffff;
-               outw(val, chan_iobase + REG_C0L);
+               /* Load the pre-load register 0 */
+               s526_gpct_write(dev, chan, data[2]);
 
                /*  Set Counter Mode Register */
                cmReg.value = data[1] & 0xffff;
                cmReg.reg.preloadRegSel = 1;    /*  PR1 */
-               outw(cmReg.value, chan_iobase + REG_C0M);
-
-               /*  Load the pre-load register 1 high word */
-               val = (data[3] >> 16) & 0xffff;
-               outw(val, chan_iobase + REG_C0H);
+               outw(cmReg.value, dev->iobase + S526_GPCT_MODE_REG(chan));
 
-               /*  Load the pre-load register 1 low word */
-               val = data[3] & 0xffff;
-               outw(val, chan_iobase + REG_C0L);
+               /* Load the pre-load register 1 */
+               s526_gpct_write(dev, chan, data[3]);
 
                /*  Write the Counter Control Register */
                if (data[4]) {
                        val = data[4] & 0xffff;
-                       outw(val, chan_iobase + REG_C0C);
+                       outw(val, dev->iobase + S526_GPCT_CTRL_REG(chan));
                }
                break;
 
@@ -352,9 +327,8 @@ static int s526_gpct_winsn(struct comedi_device *dev,
 {
        struct s526_private *devpriv = dev->private;
        unsigned int chan = CR_CHAN(insn->chanspec);
-       unsigned long chan_iobase = dev->iobase + chan * 8;
 
-       inw(chan_iobase + REG_C0M);     /* Is this read required? */
+       inw(dev->iobase + S526_GPCT_MODE_REG(chan));    /* Is this required? */
 
        /*  Check what Application of Counter this channel is configured for */
        switch (devpriv->gpct_config[chan]) {
@@ -372,8 +346,7 @@ static int s526_gpct_winsn(struct comedi_device *dev,
 
        case INSN_CONFIG_GPCT_QUADRATURE_ENCODER:
        case INSN_CONFIG_GPCT_SINGLE_PULSE_GENERATOR:
-               outw((data[0] >> 16) & 0xffff, chan_iobase + REG_C0H);
-               outw(data[0] & 0xffff, chan_iobase + REG_C0L);
+               s526_gpct_write(dev, chan, data[0]);
                break;
 
        default: