// SPDX-License-Identifier: GPL-2.0+
/*
* comedi/drivers/dt2814.c
* Hardware driver for Data Translation DT2814
*
* COMEDI - Linux Control and Measurement Device Interface
* Copyright (C) 1998 David A. Schleef <[email protected]>
*/
/*
* Driver: dt2814
* Description: Data Translation DT2814
* Author: ds
* Status: complete
* Devices: [Data Translation] DT2814 (dt2814)
*
* Configuration options:
* [0] - I/O port base address
* [1] - IRQ
*
* This card has 16 analog inputs multiplexed onto a 12 bit ADC. There
* is a minimally useful onboard clock. The base frequency for the
* clock is selected by jumpers, and the clock divider can be selected
* via programmed I/O. Unfortunately, the clock divider can only be
* a power of 10, from 1 to 10^7, of which only 3 or 4 are useful. In
* addition, the clock does not seem to be very accurate.
*/
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/comedi/comedidev.h>
#include <linux/delay.h>
#define DT2814_CSR 0
#define DT2814_DATA 1
/*
* flags
*/
#define DT2814_FINISH 0x80
#define DT2814_ERR 0x40
#define DT2814_BUSY 0x20
#define DT2814_ENB 0x10
#define DT2814_CHANMASK 0x0f
#define DT2814_TIMEOUT 10
#define DT2814_MAX_SPEED 100000 /* Arbitrary 10 khz limit */
static int dt2814_ai_notbusy(struct comedi_device *dev,
struct comedi_subdevice *s,
struct comedi_insn *insn,
unsigned long context)
{
unsigned int status;
status = inb(dev->iobase + DT2814_CSR);
if (context)
*(unsigned int *)context = status;
if (status & DT2814_BUSY)
return -EBUSY;
return 0;
}
static int dt2814_ai_clear(struct comedi_device *dev)
{
unsigned int status = 0;
int ret;
/* Wait until not busy and get status register value. */
ret = comedi_timeout(dev, NULL, NULL, dt2814_ai_notbusy,
(unsigned long)&status);
if (ret)
return ret;
if (status & (DT2814_FINISH | DT2814_ERR)) {
/*
* There unread data, or the error flag is set.
* Read the data register twice to clear the condition.
*/
inb(dev->iobase + DT2814_DATA);
inb(dev->iobase + DT2814_DATA);
}
return 0;
}
static int dt2814_ai_eoc(struct comedi_device *dev,
struct comedi_subdevice *s,
struct comedi_insn *insn,
unsigned long context)
{
unsigned int status;
status = inb(dev->iobase + DT2814_CSR);
if (status & DT2814_FINISH)
return 0;
return -EBUSY;
}
static int dt2814_ai_insn_read(struct comedi_device *dev,
struct comedi_subdevice *s,
struct comedi_insn *insn, unsigned int *data)
{
int n, hi, lo;
int chan;
int ret;
dt2814_ai_clear(dev); /* clear stale data or error */
for (n = 0; n < insn->n; n++) {
chan = CR_CHAN(insn->chanspec);
outb(chan, dev->iobase + DT2814_CSR);
ret = comedi_timeout(dev, s, insn, dt2814_ai_eoc, 0);
if (ret)
return ret;
hi = inb(dev->iobase + DT2814_DATA);
lo = inb(dev->iobase + DT2814_DATA);
data[n] = (hi << 4) | (lo >> 4);
}
return n;
}
static int dt2814_ns_to_timer(unsigned int *ns, unsigned int flags)
{
int i;
unsigned int f;
/* XXX ignores flags */
f = 10000; /* ns */
for (i = 0; i < 8; i++) {
if ((2 * (*ns)) < (f * 11))
break;
f *= 10;
}
*ns = f;
return i;
}
static int dt2814_ai_cmdtest(struct comedi_device *dev,
struct comedi_subdevice *s, struct comedi_cmd *cmd)
{
int err = 0;
unsigned int arg;
/* Step 1 : check if triggers are trivially valid */
err |= comedi_check_trigger_src(&cmd->start_src, TRIG_NOW);
err |= comedi_check_trigger_src(&cmd->scan_begin_src, TRIG_TIMER);
err |= comedi_check_trigger_src(&cmd->convert_src, TRIG_NOW);
err |= comedi_check_trigger_src(&cmd->scan_end_src, TRIG_COUNT);
err |= comedi_check_trigger_src(&cmd->stop_src, TRIG_COUNT | TRIG_NONE);
if (err)
return 1;
/* Step 2a : make sure trigger sources are unique */
err |= comedi_check_trigger_is_unique(cmd->stop_src);
/* Step 2b : and mutually compatible */
if (err)
return 2;
/* Step 3: check if arguments are trivially valid */
err |= comedi_check_trigger_arg_is(&cmd->start_arg, 0);
err |= comedi_check_trigger_arg_max(&cmd->scan_begin_arg, 1000000000);
err |= comedi_check_trigger_arg_min(&cmd->scan_begin_arg,
DT2814_MAX_SPEED);
err |= comedi_check_trigger_arg_is(&cmd->scan_end_arg,
cmd->chanlist_len);
if (cmd->stop_src == TRIG_COUNT)
err |= comedi_check_trigger_arg_min(&cmd->stop_arg, 2);
else /* TRIG_NONE */
err |= comedi_check_trigger_arg_is(&cmd->stop_arg, 0);
if (err)
return 3;
/* step 4: fix up any arguments */
arg = cmd->scan_begin_arg;
dt2814_ns_to_timer(&arg, cmd->flags);
err |= comedi_check_trigger_arg_is(&cmd->scan_begin_arg, arg);
if (err)
return 4;
return 0;
}
static int dt2814_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
{
struct comedi_cmd *cmd = &s->async->cmd;
int chan;
int trigvar;
dt2814_ai_clear(dev); /* clear stale data or error */
trigvar = dt2814_ns_to_timer(&cmd->scan_begin_arg, cmd->flags);
chan = CR_CHAN(cmd->chanlist[0]);
outb(chan | DT2814_ENB | (trigvar << 5), dev->iobase + DT2814_CSR);
return 0;
}
static int dt2814_ai_cancel(struct comedi_device *dev,
struct comedi_subdevice *s)
{
unsigned int status;
unsigned long flags;
spin_lock_irqsave(&dev->spinlock, flags);
status = inb(dev->iobase + DT2814_CSR);
if (status & DT2814_ENB) {
/*
* Clear the timed trigger enable bit.
*
* Note: turning off timed mode triggers another
* sample. This will be mopped up by the calls to
* dt2814_ai_clear().
*/
outb(status & DT2814_CHANMASK, dev->iobase + DT2814_CSR);
}
spin_unlock_irqrestore(&dev->spinlock, flags);
return 0;
}
static irqreturn_t dt2814_interrupt(int irq, void *d)
{
struct comedi_device *dev = d;
struct comedi_subdevice *s = dev->read_subdev;
struct comedi_async *async;
unsigned int lo, hi;
unsigned short data;
unsigned int status;
if (!dev->attached) {
dev_err(dev->class_dev, "spurious interrupt\n");
return IRQ_HANDLED;
}
async = s->async;
spin_lock(&dev->spinlock);
status = inb(dev->iobase + DT2814_CSR);
if (!(status & DT2814_ENB)) {
/* Timed acquisition not enabled. Nothing to do. */
spin_unlock(&dev->spinlock);
return IRQ_HANDLED;
}
if (!(status & (DT2814_FINISH | DT2814_ERR))) {
/* Spurious interrupt? */
spin_unlock(&dev->spinlock);
return IRQ_HANDLED;
}
/* Read data or clear error. */
hi = inb(dev->iobase + DT2814_DATA);
lo = inb(dev->iobase + DT2814_DATA);
data = (hi << 4) | (lo >> 4);
if (status & DT2814_ERR) {
async->events |= COMEDI_CB_ERROR;
} else {
comedi_buf_write_samples(s, &data, 1);
if (async->cmd.stop_src == TRIG_COUNT &&
async->scans_done >= async->cmd.stop_arg) {
async->events |= COMEDI_CB_EOA;
}
}
if (async->events & COMEDI_CB_CANCEL_MASK) {
/*
* Disable timed mode.
*
* Note: turning off timed mode triggers another
* sample. This will be mopped up by the calls to
* dt2814_ai_clear().
*/
outb(status & DT2814_CHANMASK, dev->iobase + DT2814_CSR);
}
spin_unlock(&dev->spinlock);
comedi_handle_events(dev, s);
return IRQ_HANDLED;
}
static int dt2814_attach(struct comedi_device *dev, struct comedi_devconfig *it)
{
struct comedi_subdevice *s;
int ret;
ret = comedi_request_region(dev, it->options[0], 0x2);
if (ret)
return ret;
outb(0, dev->iobase + DT2814_CSR);
if (dt2814_ai_clear(dev)) {
dev_err(dev->class_dev, "reset error (fatal)\n");
return -EIO;
}
if (it->options[1]) {
ret = request_irq(it->options[1], dt2814_interrupt, 0,
dev->board_name, dev);
if (ret == 0)
dev->irq = it->options[1];
}
ret = comedi_alloc_subdevices(dev, 1);
if (ret)
return ret;
s = &dev->subdevices[0];
s->type = COMEDI_SUBD_AI;
s->subdev_flags = SDF_READABLE | SDF_GROUND;
s->n_chan = 16; /* XXX */
s->insn_read = dt2814_ai_insn_read;
s->maxdata = 0xfff;
s->range_table = &range_unknown; /* XXX */
if (dev->irq) {
dev->read_subdev = s;
s->subdev_flags |= SDF_CMD_READ;
s->len_chanlist = 1;
s->do_cmd = dt2814_ai_cmd;
s->do_cmdtest = dt2814_ai_cmdtest;
s->cancel = dt2814_ai_cancel;
}
return 0;
}
static void dt2814_detach(struct comedi_device *dev)
{
if (dev->irq) {
/*
* An extra conversion triggered on termination of an
* asynchronous command may still be in progress. Wait for
* it to finish and clear the data or error status.
*/
dt2814_ai_clear(dev);
}
comedi_legacy_detach(dev);
}
static struct comedi_driver dt2814_driver = {
.driver_name = "dt2814",
.module = THIS_MODULE,
.attach = dt2814_attach,
.detach = dt2814_detach,
};
module_comedi_driver(dt2814_driver);
MODULE_AUTHOR("Comedi https://www.comedi.org");
MODULE_DESCRIPTION("Comedi low-level driver");
MODULE_LICENSE("GPL");
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