staging: comedi: adv_pci_dio: simplify counter subdevice I/O

Only two of the boards supported by this driver have an 8254 counter/timer.
Both of these boards have a single 8254 device. Currently the counter
subdevice functions are coded to support multiple 8254 devices. This is
unnecessary and just complicates the code.

Simplfy the subdevice functions to work for a single 8254 counter/timer and
refactor the driver (*attach) accordingly.

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/adv_pci_dio.c b/drivers/staging/comedi/drivers/adv_pci_dio.c
index 09609d6d02da283210493b9c25ed981ccd693e88..88244509beb7e0b68cc9787045eac6f9168d41b5 100644 (file)
--- a/drivers/staging/comedi/drivers/adv_pci_dio.c
+++ b/drivers/staging/comedi/drivers/adv_pci_dio.c
@@ -60,12 +60,6 @@ enum hw_io_access {
 #define MAX_DO_SUBDEVS 2       /* max number of DO subdevices per card */
 #define MAX_DIO_SUBDEVG        2       /* max number of DIO subdevices group per
                                 * card */
-#define MAX_8254_SUBDEVS   1   /* max number of 8254 counter subdevs per
-                                * card */
-                               /* (could be more than one 8254 per
-                                * subdevice) */
-
-#define SIZE_8254         4    /* 8254 IO space length */
 
 #define PCIDIO_MAINREG    2    /* main I/O region for all Advantech cards? */
 
@@ -243,7 +237,7 @@ struct dio_boardtype {
        struct diosubd_data sdo[MAX_DO_SUBDEVS];        /*  DO chans */
        struct diosubd_data sdio[MAX_DIO_SUBDEVG];      /*  DIO 8255 chans */
        struct diosubd_data boardid;    /*  card supports board ID switch */
-       struct diosubd_data s8254[MAX_8254_SUBDEVS];    /* 8254 subdevices */
+       struct diosubd_data s8254[1];   /* 8254 subdevices */
        enum hw_io_access io_access;
 };
 
@@ -492,15 +486,11 @@ static int pci_8254_insn_read(struct comedi_device *dev,
                              struct comedi_insn *insn, unsigned int *data)
 {
        const struct diosubd_data *d = (const struct diosubd_data *)s->private;
-       unsigned int chan, chip, chipchan;
+       unsigned int chan = CR_CHAN(insn->chanspec);
        unsigned long flags;
 
-       chan = CR_CHAN(insn->chanspec); /* channel on subdevice */
-       chip = chan / 3;                /* chip on subdevice */
-       chipchan = chan - (3 * chip);   /* channel on chip on subdevice */
        spin_lock_irqsave(&s->spin_lock, flags);
-       data[0] = i8254_read(dev->iobase + d->addr + (SIZE_8254 * chip),
-                       0, chipchan);
+       data[0] = i8254_read(dev->iobase + d->addr, 0, chan);
        spin_unlock_irqrestore(&s->spin_lock, flags);
        return 1;
 }
@@ -513,15 +503,11 @@ static int pci_8254_insn_write(struct comedi_device *dev,
                               struct comedi_insn *insn, unsigned int *data)
 {
        const struct diosubd_data *d = (const struct diosubd_data *)s->private;
-       unsigned int chan, chip, chipchan;
+       unsigned int chan = CR_CHAN(insn->chanspec);
        unsigned long flags;
 
-       chan = CR_CHAN(insn->chanspec); /* channel on subdevice */
-       chip = chan / 3;                /* chip on subdevice */
-       chipchan = chan - (3 * chip);   /* channel on chip on subdevice */
        spin_lock_irqsave(&s->spin_lock, flags);
-       i8254_write(dev->iobase + d->addr + (SIZE_8254 * chip),
-                       0, chipchan, data[0]);
+       i8254_write(dev->iobase + d->addr, 0, chan, data[0]);
        spin_unlock_irqrestore(&s->spin_lock, flags);
        return 1;
 }
@@ -534,24 +520,20 @@ static int pci_8254_insn_config(struct comedi_device *dev,
                                struct comedi_insn *insn, unsigned int *data)
 {
        const struct diosubd_data *d = (const struct diosubd_data *)s->private;
-       unsigned int chan, chip, chipchan;
-       unsigned long iobase;
+       unsigned int chan = CR_CHAN(insn->chanspec);
+       unsigned long iobase = dev->iobase + d->addr;
        int ret = 0;
        unsigned long flags;
 
-       chan = CR_CHAN(insn->chanspec); /* channel on subdevice */
-       chip = chan / 3;                /* chip on subdevice */
-       chipchan = chan - (3 * chip);   /* channel on chip on subdevice */
-       iobase = dev->iobase + d->addr + (SIZE_8254 * chip);
        spin_lock_irqsave(&s->spin_lock, flags);
        switch (data[0]) {
        case INSN_CONFIG_SET_COUNTER_MODE:
-               ret = i8254_set_mode(iobase, 0, chipchan, data[1]);
+               ret = i8254_set_mode(iobase, 0, chan, data[1]);
                if (ret < 0)
                        ret = -EINVAL;
                break;
        case INSN_CONFIG_8254_READ_STATUS:
-               data[1] = i8254_status(iobase, 0, chipchan);
+               data[1] = i8254_status(iobase, 0, chan);
                break;
        default:
                ret = -EINVAL;
@@ -1144,12 +1126,11 @@ static int pci_dio_auto_attach(struct comedi_device *dev,
                subdev++;
        }
 
-       for (i = 0; i < MAX_8254_SUBDEVS; i++)
-               if (this_board->s8254[i].chans) {
-                       s = &dev->subdevices[subdev];
-                       pci_dio_add_8254(dev, s, &this_board->s8254[i]);
-                       subdev++;
-               }
+       if (this_board->s8254[0].chans) {
+               s = &dev->subdevices[subdev];
+               pci_dio_add_8254(dev, s, &this_board->s8254[0]);
+               subdev++;
+       }
 
        if (this_board->cardtype == TYPE_PCI1760)
                pci1760_attach(dev);