amplc_dio200: Internalize 8255 DIO subdevice implementation

Implement the 8255 DIO subdevice internally to this module instead of
using the external '8255' kernel module.  This will allow the subdevice
to be enhanced with extra features at a later date (for new cards).

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>

diff --git a/comedi/drivers/amplc_dio200.c b/comedi/drivers/amplc_dio200.c
index 83b9a52abea053196fa5d2daeea10dd51e6e00ce..628b7c71362066ebd452947880f933aaeefc7f0e 100644 (file)
--- a/comedi/drivers/amplc_dio200.c
+++ b/comedi/drivers/amplc_dio200.c
@@ -220,6 +220,15 @@ order they appear in the channel list.
 #define PCI_DEVICE_ID_AMPLICON_PCI215 0x000b
 #define PCI_DEVICE_ID_INVALID 0xffff
 
+/* 8255 control register bits */
+#define CR_C_LO_IO     0x01
+#define CR_B_IO                0x02
+#define CR_B_MODE      0x04
+#define CR_C_HI_IO     0x08
+#define CR_A_IO                0x10
+#define CR_A_MODE(a)   ((a)<<5)
+#define CR_CW          0x80
+
 /* 200 series registers */
 #define DIO200_IO_SIZE         0x20
 #define DIO200_XCLK_SCE                0x18    /* Group X clock selection register */
@@ -456,6 +465,10 @@ typedef struct {
        spinlock_t spinlock;
 } dio200_subdev_8254;
 
+typedef struct {
+       unsigned int ofs;               /* DIO base offset */
+} dio200_subdev_8255;
+
 typedef struct {
        unsigned int ofs;
        spinlock_t spinlock;
@@ -1282,6 +1295,152 @@ dio200_subdev_8254_cleanup(comedi_device * dev, comedi_subdevice * s)
        }
 }
 
+/*
+ * This function sets I/O directions for an '8255' DIO subdevice.
+ */
+static void
+dio200_subdev_8255_set_dir(comedi_device * dev, comedi_subdevice * s)
+{
+       dio200_subdev_8255 *subpriv = s->private;
+       int config;
+
+       config = CR_CW;
+       /* 1 in io_bits indicates output, 1 in config indicates input */
+       if (!(s->io_bits & 0x0000ff))
+               config |= CR_A_IO;
+       if (!(s->io_bits & 0x00ff00))
+               config |= CR_B_IO;
+       if (!(s->io_bits & 0x0f0000))
+               config |= CR_C_LO_IO;
+       if (!(s->io_bits & 0xf00000))
+               config |= CR_C_HI_IO;
+
+       outb(config, dev->iobase + (subpriv->ofs + 3));
+}
+
+/*
+ * Handle 'insn_bits' for an '8255' DIO subdevice.
+ */
+static int
+dio200_subdev_8255_bits(comedi_device * dev, comedi_subdevice * s,
+       comedi_insn * insn, lsampl_t * data)
+{
+       dio200_subdev_8255 *subpriv = s->private;
+
+       if (data[0]) {
+               s->state &= ~data[0];
+               s->state |= (data[0] & data[1]);
+
+               if (data[0] & 0xff) {
+                       outb(s->state & 0xff, dev->iobase + subpriv->ofs);
+               }
+               if (data[0] & 0xff00) {
+                       outb((s->state >> 8) & 0xff,
+                               dev->iobase + (subpriv->ofs + 1));
+               }
+               if (data[0] & 0xff0000) {
+                       outb((s->state >> 16) & 0xff,
+                               dev->iobase + (subpriv->ofs + 2));
+               }
+       }
+
+       data[1] = inb(dev->iobase + subpriv->ofs);
+       data[1] |= inb(dev->iobase + (subpriv->ofs + 1)) << 8;
+       data[1] |= inb(dev->iobase + (subpriv->ofs + 2)) << 16;
+
+       return 2;
+}
+
+/*
+ * Handle 'insn_config' for an '8255' DIO subdevice.
+ */
+static int
+dio200_subdev_8255_config(comedi_device * dev, comedi_subdevice * s,
+       comedi_insn * insn, lsampl_t * data)
+{
+       unsigned int mask;
+       unsigned int bits;
+
+       mask = 1 << CR_CHAN(insn->chanspec);
+       if (mask & 0x0000ff) {
+               bits = 0x0000ff;
+       } else if (mask & 0x00ff00) {
+               bits = 0x00ff00;
+       } else if (mask & 0x0f0000) {
+               bits = 0x0f0000;
+       } else {
+               bits = 0xf00000;
+       }
+
+       switch (data[0]) {
+       case INSN_CONFIG_DIO_INPUT:
+               s->io_bits &= ~bits;
+               break;
+       case INSN_CONFIG_DIO_OUTPUT:
+               s->io_bits |= bits;
+               break;
+       case INSN_CONFIG_DIO_QUERY:
+               data[1] = (s->io_bits & bits) ? COMEDI_OUTPUT : COMEDI_INPUT;
+               return insn->n;
+               break;
+       default:
+               return -EINVAL;
+       }
+
+       dio200_subdev_8255_set_dir(dev, s);
+
+       return 1;
+}
+
+/*
+ * This function initializes an '8255' DIO subdevice.
+ *
+ * offset is the offset to the 8255 chip.
+ */
+static int
+dio200_subdev_8255_init(comedi_device * dev, comedi_subdevice * s,
+       unsigned int offset)
+{
+       dio200_subdev_8255 *subpriv;
+
+       subpriv = kzalloc(sizeof(*subpriv), GFP_KERNEL);
+       if (!subpriv) {
+               printk(KERN_ERR "comedi%d: error! out of memory!\n",
+                       dev->minor);
+               return -ENOMEM;
+       }
+
+       subpriv->ofs = offset;
+
+       s->private = subpriv;
+       s->type = COMEDI_SUBD_DIO;
+       s->subdev_flags = SDF_READABLE | SDF_WRITABLE;
+       s->n_chan = 24;
+       s->range_table = &range_digital;
+       s->maxdata = 1;
+       s->insn_bits = dio200_subdev_8255_bits;
+       s->insn_config = dio200_subdev_8255_config;
+
+       s->state = 0;
+       s->io_bits = 0;
+       dio200_subdev_8255_set_dir(dev, s);
+
+       return 0;
+}
+
+/*
+ * This function cleans up an '8255' DIO subdevice.
+ */
+static void
+dio200_subdev_8255_cleanup(comedi_device * dev, comedi_subdevice * s)
+{
+       dio200_subdev_8255 *subpriv = s->private;
+
+       if (subpriv) {
+               kfree(subpriv);
+       }
+}
+
 /*
  * Attach is called by the Comedi core to configure the driver
  * for a particular board.  If you specified a board_name array
@@ -1382,8 +1541,8 @@ static int dio200_attach(comedi_device * dev, comedi_devconfig * it)
                        break;
                case sd_8255:
                        /* digital i/o subdevice (8255) */
-                       ret = subdev_8255_init(dev, s, 0,
-                               iobase + layout->sdinfo[n]);
+                       ret = dio200_subdev_8255_init(dev, s,
+                               layout->sdinfo[n]);
                        if (ret < 0) {
                                return ret;
                        }
@@ -1474,7 +1633,7 @@ static int dio200_detach(comedi_device * dev)
                                dio200_subdev_8254_cleanup(dev, s);
                                break;
                        case sd_8255:
-                               subdev_8255_cleanup(dev, s);
+                               dio200_subdev_8255_cleanup(dev, s);
                                break;
                        case sd_intr:
                                dio200_subdev_intr_cleanup(dev, s);