--- /dev/null
+/*
+ kcomedilib/kcomedilib.c
+ a comedlib interface for kernel modules
+
+ COMEDI - Linux Control and Measurement Device Interface
+ Copyright (C) 1997-2000 David A. Schleef <ds@schleef.org>
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+*/
+
+#include <linux/module.h>
+
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/fcntl.h>
+#include <linux/mm.h>
+#include <linux/io.h>
+
+#include "../comedi.h"
+#include "../comedilib.h"
+#include "../comedidev.h"
+
+MODULE_AUTHOR("David Schleef <ds@schleef.org>");
+MODULE_DESCRIPTION("Comedi kernel library");
+MODULE_LICENSE("GPL");
+
+struct comedi_device *comedi_open(const char *filename)
+{
+ struct comedi_device *dev, *retval = NULL;
+ unsigned int minor;
+
+ if (strncmp(filename, "/dev/comedi", 11) != 0)
+ return NULL;
+
+ if (kstrtouint(filename + 11, 0, &minor))
+ return NULL;
+
+ if (minor >= COMEDI_NUM_BOARD_MINORS)
+ return NULL;
+
+ dev = comedi_dev_get_from_minor(minor);
+ if (!dev)
+ return NULL;
+
+ down_read(&dev->attach_lock);
+ if (dev->attached)
+ retval = dev;
+ else
+ retval = NULL;
+ up_read(&dev->attach_lock);
+
+ if (!retval)
+ comedi_dev_put(dev);
+
+ return retval;
+}
+EXPORT_SYMBOL_GPL(comedi_open);
+
+int comedi_close(struct comedi_device *dev)
+{
+ comedi_dev_put(dev);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(comedi_close);
+
+static int comedi_do_insn(struct comedi_device *dev,
+ struct comedi_insn *insn,
+ unsigned int *data)
+{
+ struct comedi_subdevice *s;
+ int ret;
+
+ mutex_lock(&dev->mutex);
+
+ if (!dev->attached) {
+ ret = -EINVAL;
+ goto error;
+ }
+
+ /* a subdevice instruction */
+ if (insn->subdev >= dev->n_subdevices) {
+ ret = -EINVAL;
+ goto error;
+ }
+ s = &dev->subdevices[insn->subdev];
+
+ if (s->type == COMEDI_SUBD_UNUSED) {
+ dev_err(dev->class_dev,
+ "%d not usable subdevice\n", insn->subdev);
+ ret = -EIO;
+ goto error;
+ }
+
+ /* XXX check lock */
+
+ ret = comedi_check_chanlist(s, 1, &insn->chanspec);
+ if (ret < 0) {
+ dev_err(dev->class_dev, "bad chanspec\n");
+ ret = -EINVAL;
+ goto error;
+ }
+
+ if (s->busy) {
+ ret = -EBUSY;
+ goto error;
+ }
+ s->busy = dev;
+
+ switch (insn->insn) {
+ case INSN_BITS:
+ ret = s->insn_bits(dev, s, insn, data);
+ break;
+ case INSN_CONFIG:
+ /* XXX should check instruction length */
+ ret = s->insn_config(dev, s, insn, data);
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+ s->busy = NULL;
+error:
+
+ mutex_unlock(&dev->mutex);
+ return ret;
+}
+
+int comedi_dio_get_config(struct comedi_device *dev, unsigned int subdev,
+ unsigned int chan, unsigned int *io)
+{
+ struct comedi_insn insn;
+ unsigned int data[2];
+ int ret;
+
+ memset(&insn, 0, sizeof(insn));
+ insn.insn = INSN_CONFIG;
+ insn.n = 2;
+ insn.subdev = subdev;
+ insn.chanspec = CR_PACK(chan, 0, 0);
+ data[0] = INSN_CONFIG_DIO_QUERY;
+ data[1] = 0;
+ ret = comedi_do_insn(dev, &insn, data);
+ if (ret >= 0)
+ *io = data[1];
+ return ret;
+}
+EXPORT_SYMBOL_GPL(comedi_dio_get_config);
+
+int comedi_dio_config(struct comedi_device *dev, unsigned int subdev,
+ unsigned int chan, unsigned int io)
+{
+ struct comedi_insn insn;
+
+ memset(&insn, 0, sizeof(insn));
+ insn.insn = INSN_CONFIG;
+ insn.n = 1;
+ insn.subdev = subdev;
+ insn.chanspec = CR_PACK(chan, 0, 0);
+
+ return comedi_do_insn(dev, &insn, &io);
+}
+EXPORT_SYMBOL_GPL(comedi_dio_config);
+
+int comedi_dio_bitfield2(struct comedi_device *dev, unsigned int subdev,
+ unsigned int mask, unsigned int *bits,
+ unsigned int base_channel)
+{
+ struct comedi_insn insn;
+ unsigned int data[2];
+ unsigned int n_chan;
+ unsigned int shift;
+ int ret;
+
+ base_channel = CR_CHAN(base_channel);
+ n_chan = comedi_get_n_channels(dev, subdev);
+ if (base_channel >= n_chan)
+ return -EINVAL;
+
+ memset(&insn, 0, sizeof(insn));
+ insn.insn = INSN_BITS;
+ insn.chanspec = base_channel;
+ insn.n = 2;
+ insn.subdev = subdev;
+
+ data[0] = mask;
+ data[1] = *bits;
+
+ /*
+ * Most drivers ignore the base channel in insn->chanspec.
+ * Fix this here if the subdevice has <= 32 channels.
+ */
+ if (n_chan <= 32) {
+ shift = base_channel;
+ if (shift) {
+ insn.chanspec = 0;
+ data[0] <<= shift;
+ data[1] <<= shift;
+ }
+ } else {
+ shift = 0;
+ }
+
+ ret = comedi_do_insn(dev, &insn, data);
+ *bits = data[1] >> shift;
+ return ret;
+}
+EXPORT_SYMBOL_GPL(comedi_dio_bitfield2);
+
+int comedi_find_subdevice_by_type(struct comedi_device *dev, int type,
+ unsigned int subd)
+{
+ struct comedi_subdevice *s;
+ int ret = -ENODEV;
+
+ down_read(&dev->attach_lock);
+ if (dev->attached)
+ for (; subd < dev->n_subdevices; subd++) {
+ s = &dev->subdevices[subd];
+ if (s->type == type) {
+ ret = subd;
+ break;
+ }
+ }
+ up_read(&dev->attach_lock);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(comedi_find_subdevice_by_type);
+
+int comedi_get_n_channels(struct comedi_device *dev, unsigned int subdevice)
+{
+ int n;
+
+ down_read(&dev->attach_lock);
+ if (!dev->attached || subdevice >= dev->n_subdevices)
+ n = 0;
+ else
+ n = dev->subdevices[subdevice].n_chan;
+ up_read(&dev->attach_lock);
+
+ return n;
+}
+EXPORT_SYMBOL_GPL(comedi_get_n_channels);
Code Review / kvmfornfv.git / blobdiff