staging: comedi: pcmuio: introduce pcmuio_write()

Introduce a helper function to handle writing a 24-bit value to the
three 8-bit registers associated with a "port" or "page".

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/pcmuio.c b/drivers/staging/comedi/drivers/pcmuio.c
index 3c98a00..d882bb3 100644 (file)
--- a/drivers/staging/comedi/drivers/pcmuio.c
+++ b/drivers/staging/comedi/drivers/pcmuio.c
@@ -126,8 +126,6 @@
 #define PCMUIO96_IOSIZE                (ASIC_IOSIZE * 2)
 
 #define NUM_PAGED_REGS         3
-#define NUM_PAGES              4
-#define FIRST_PAGED_REG                0x8
 
 struct pcmuio_board {
        const char *name;
@@ -194,6 +192,24 @@ struct pcmuio_private {
        struct pcmuio_subdev_private *sprivs;
 };
 
+static void pcmuio_write(struct comedi_device *dev, unsigned int val,
+                        int asic, int page, int port)
+{
+       unsigned long iobase = dev->iobase + (asic * ASIC_IOSIZE);
+
+       if (page == 0) {
+               /* Port registers are valid for any page */
+               outb(val & 0xff, iobase + PCMUIO_PORT_REG(port + 0));
+               outb((val >> 8) & 0xff, iobase + PCMUIO_PORT_REG(port + 1));
+               outb((val >> 16) & 0xff, iobase + PCMUIO_PORT_REG(port + 2));
+       } else {
+               outb(PCMUIO_PAGE(page), iobase + PCMUIO_PAGE_LOCK_REG);
+               outb(val & 0xff, iobase + PCMUIO_PAGE_REG(0));
+               outb((val >> 8) & 0xff, iobase + PCMUIO_PAGE_REG(1));
+               outb((val >> 16) & 0xff, iobase + PCMUIO_PAGE_REG(2));
+       }
+}
+
 static int pcmuio_dio_insn_bits(struct comedi_device *dev,
                                struct comedi_subdevice *s,
                                struct comedi_insn *insn, unsigned int *data)
@@ -315,42 +331,27 @@ static void switch_page(struct comedi_device *dev, int asic, int page)
 }
 
 static void init_asics(struct comedi_device *dev)
-{                              /* sets up an
-                                  ASIC chip to defaults */
+{
        const struct pcmuio_board *board = comedi_board(dev);
        int asic;
 
        for (asic = 0; asic < board->num_asics; ++asic) {
-               int port, page;
-               unsigned long baseaddr = dev->iobase + asic * ASIC_IOSIZE;
-
-               switch_page(dev, asic, 0);      /* switch back to page 0 */
-
                /* first, clear all the DIO port bits */
-               for (port = 0; port < PORTS_PER_ASIC; ++port)
-                       outb(0, baseaddr + PCMUIO_PORT_REG(port));
+               pcmuio_write(dev, 0, asic, 0, 0);
+               pcmuio_write(dev, 0, asic, 0, 3);
 
                /* Next, clear all the paged registers for each page */
-               for (page = 1; page < NUM_PAGES; ++page) {
-                       int reg;
-                       /* now clear all the paged registers */
-                       switch_page(dev, asic, page);
-                       for (reg = FIRST_PAGED_REG;
-                            reg < FIRST_PAGED_REG + NUM_PAGED_REGS; ++reg)
-                               outb(0, baseaddr + reg);
-               }
-
-               /* switch back to default page 0 */
-               switch_page(dev, asic, 0);
+               pcmuio_write(dev, 0, asic, PCMUIO_PAGE_POL, 0);
+               pcmuio_write(dev, 0, asic, PCMUIO_PAGE_ENAB, 0);
+               pcmuio_write(dev, 0, asic, PCMUIO_PAGE_INT_ID, 0);
        }
 }
 
 static void pcmuio_stop_intr(struct comedi_device *dev,
                             struct comedi_subdevice *s)
 {
-       struct pcmuio_private *devpriv = dev->private;
        struct pcmuio_subdev_private *subpriv = s->private;
-       int nports, firstport, asic, port;
+       int asic;
 
        asic = subpriv->intr.asic;
        if (asic < 0)
@@ -359,13 +360,9 @@ static void pcmuio_stop_intr(struct comedi_device *dev,
        subpriv->intr.enabled_mask = 0;
        subpriv->intr.active = 0;
        s->async->inttrig = NULL;
-       nports = subpriv->intr.num_asic_chans / CHANS_PER_PORT;
-       firstport = subpriv->intr.asic_chan / CHANS_PER_PORT;
-       switch_page(dev, asic, PCMUIO_PAGE_ENAB);
-       for (port = firstport; port < firstport + nports; ++port) {
-               /* disable all intrs for this subdev.. */
-               outb(0, devpriv->asics[asic].iobase + PCMUIO_PAGE_REG(port));
-       }
+
+       /* disable all intrs for this subdev.. */
+       pcmuio_write(dev, 0, asic, PCMUIO_PAGE_ENAB, 0);
 }
 
 static void pcmuio_handle_intr_subdev(struct comedi_device *dev,
@@ -503,7 +500,6 @@ static irqreturn_t interrupt_pcmuio(int irq, void *d)
 static int pcmuio_start_intr(struct comedi_device *dev,
                             struct comedi_subdevice *s)
 {
-       struct pcmuio_private *devpriv = dev->private;
        struct pcmuio_subdev_private *subpriv = s->private;
 
        if (!subpriv->intr.continuous && subpriv->intr.stop_count == 0) {
@@ -513,7 +509,7 @@ static int pcmuio_start_intr(struct comedi_device *dev,
                return 1;
        } else {
                unsigned bits = 0, pol_bits = 0, n;
-               int nports, firstport, asic, port;
+               int asic;
                struct comedi_cmd *cmd = &s->async->cmd;
 
                asic = subpriv->intr.asic;
@@ -522,8 +518,6 @@ static int pcmuio_start_intr(struct comedi_device *dev,
                                           subdev */
                subpriv->intr.enabled_mask = 0;
                subpriv->intr.active = 1;
-               nports = subpriv->intr.num_asic_chans / CHANS_PER_PORT;
-               firstport = subpriv->intr.asic_chan / CHANS_PER_PORT;
                if (cmd->chanlist) {
                        for (n = 0; n < cmd->chanlist_len; n++) {
                                bits |= (1U << CR_CHAN(cmd->chanlist[n]));
@@ -537,21 +531,9 @@ static int pcmuio_start_intr(struct comedi_device *dev,
                         1) << subpriv->intr.first_chan;
                subpriv->intr.enabled_mask = bits;
 
-               switch_page(dev, asic, PCMUIO_PAGE_ENAB);
-               for (port = firstport; port < firstport + nports; ++port) {
-                       unsigned enab =
-                           bits >> (subpriv->intr.first_chan + (port -
-                                                                firstport) *
-                                    8) & 0xff, pol =
-                           pol_bits >> (subpriv->intr.first_chan +
-                                        (port - firstport) * 8) & 0xff;
-                       /* set enab intrs for this subdev.. */
-                       outb(enab,
-                            devpriv->asics[asic].iobase + PCMUIO_PAGE_REG(port));
-                       switch_page(dev, asic, PCMUIO_PAGE_POL);
-                       outb(pol,
-                            devpriv->asics[asic].iobase + PCMUIO_PAGE_REG(port));
-               }
+               /* set pol and enab intrs for this subdev.. */
+               pcmuio_write(dev, pol_bits, asic, PCMUIO_PAGE_POL, 0);
+               pcmuio_write(dev, bits, asic, PCMUIO_PAGE_ENAB, 0);
        }
        return 0;
 }