linux/drivers/comedi/range.c
Greg Kroah-Hartman 8ffdff6a8c staging: comedi: move out of staging directory
The comedi code came into the kernel back in 2008, but traces its
lifetime to much much earlier.  It's been polished and buffed and
there's really nothing preventing it from being part of the "real"
portion of the kernel.

So move it to drivers/comedi/ as it belongs there.

Many thanks to the hundreds of developers who did the work to make this
happen.

Cc: Ian Abbott <abbotti@mev.co.uk>
Cc: H Hartley Sweeten <hsweeten@visionengravers.com>
Link: https://lore.kernel.org/r/YHauop4u3sP6lz8j@kroah.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-15 09:26:25 +02:00

132 lines
3.8 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* comedi/range.c
* comedi routines for voltage ranges
*
* COMEDI - Linux Control and Measurement Device Interface
* Copyright (C) 1997-8 David A. Schleef <ds@schleef.org>
*/
#include <linux/uaccess.h>
#include "comedidev.h"
#include "comedi_internal.h"
const struct comedi_lrange range_bipolar10 = { 1, {BIP_RANGE(10)} };
EXPORT_SYMBOL_GPL(range_bipolar10);
const struct comedi_lrange range_bipolar5 = { 1, {BIP_RANGE(5)} };
EXPORT_SYMBOL_GPL(range_bipolar5);
const struct comedi_lrange range_bipolar2_5 = { 1, {BIP_RANGE(2.5)} };
EXPORT_SYMBOL_GPL(range_bipolar2_5);
const struct comedi_lrange range_unipolar10 = { 1, {UNI_RANGE(10)} };
EXPORT_SYMBOL_GPL(range_unipolar10);
const struct comedi_lrange range_unipolar5 = { 1, {UNI_RANGE(5)} };
EXPORT_SYMBOL_GPL(range_unipolar5);
const struct comedi_lrange range_unipolar2_5 = { 1, {UNI_RANGE(2.5)} };
EXPORT_SYMBOL_GPL(range_unipolar2_5);
const struct comedi_lrange range_0_20mA = { 1, {RANGE_mA(0, 20)} };
EXPORT_SYMBOL_GPL(range_0_20mA);
const struct comedi_lrange range_4_20mA = { 1, {RANGE_mA(4, 20)} };
EXPORT_SYMBOL_GPL(range_4_20mA);
const struct comedi_lrange range_0_32mA = { 1, {RANGE_mA(0, 32)} };
EXPORT_SYMBOL_GPL(range_0_32mA);
const struct comedi_lrange range_unknown = { 1, {{0, 1000000, UNIT_none} } };
EXPORT_SYMBOL_GPL(range_unknown);
/*
* COMEDI_RANGEINFO ioctl
* range information
*
* arg:
* pointer to comedi_rangeinfo structure
*
* reads:
* comedi_rangeinfo structure
*
* writes:
* array of comedi_krange structures to rangeinfo->range_ptr pointer
*/
int do_rangeinfo_ioctl(struct comedi_device *dev,
struct comedi_rangeinfo *it)
{
int subd, chan;
const struct comedi_lrange *lr;
struct comedi_subdevice *s;
subd = (it->range_type >> 24) & 0xf;
chan = (it->range_type >> 16) & 0xff;
if (!dev->attached)
return -EINVAL;
if (subd >= dev->n_subdevices)
return -EINVAL;
s = &dev->subdevices[subd];
if (s->range_table) {
lr = s->range_table;
} else if (s->range_table_list) {
if (chan >= s->n_chan)
return -EINVAL;
lr = s->range_table_list[chan];
} else {
return -EINVAL;
}
if (RANGE_LENGTH(it->range_type) != lr->length) {
dev_dbg(dev->class_dev,
"wrong length %d should be %d (0x%08x)\n",
RANGE_LENGTH(it->range_type),
lr->length, it->range_type);
return -EINVAL;
}
if (copy_to_user(it->range_ptr, lr->range,
sizeof(struct comedi_krange) * lr->length))
return -EFAULT;
return 0;
}
/**
* comedi_check_chanlist() - Validate each element in a chanlist.
* @s: comedi_subdevice struct
* @n: number of elements in the chanlist
* @chanlist: the chanlist to validate
*
* Each element consists of a channel number, a range index, an analog
* reference type and some flags, all packed into an unsigned int.
*
* This checks that the channel number and range index are supported by
* the comedi subdevice. It does not check whether the analog reference
* type and the flags are supported. Drivers that care should check those
* themselves.
*
* Return: %0 if all @chanlist elements are valid (success),
* %-EINVAL if one or more elements are invalid.
*/
int comedi_check_chanlist(struct comedi_subdevice *s, int n,
unsigned int *chanlist)
{
struct comedi_device *dev = s->device;
unsigned int chanspec;
int chan, range_len, i;
for (i = 0; i < n; i++) {
chanspec = chanlist[i];
chan = CR_CHAN(chanspec);
if (s->range_table)
range_len = s->range_table->length;
else if (s->range_table_list && chan < s->n_chan)
range_len = s->range_table_list[chan]->length;
else
range_len = 0;
if (chan >= s->n_chan ||
CR_RANGE(chanspec) >= range_len) {
dev_warn(dev->class_dev,
"bad chanlist[%d]=0x%08x chan=%d range length=%d\n",
i, chanspec, chan, range_len);
return -EINVAL;
}
}
return 0;
}
EXPORT_SYMBOL_GPL(comedi_check_chanlist);