* Comedi driver for Data Translation DT2811
*
* COMEDI - Linux Control and Measurement Device Interface
- * History:
- * Base Version - David A. Schleef <ds@schleef.org>
- * December 1998 - Updated to work. David does not have a DT2811
- * board any longer so this was suffering from bitrot.
- * Updated performed by ...
+ * Copyright (C) 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
*
* Configuration options:
* [0] - I/O port base address
- * [1] - IRQ, although this is currently unused
+ * [1] - IRQ (optional, needed for async command support)
* [2] - A/D reference (# of analog inputs)
* 0 = single-ended (16 channels)
* 1 = differential (8 channels)
*/
#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+
#include "../comedidev.h"
/*
#define DT2811_ADCSR_ADERROR BIT(6) /* r 1=A/D error */
#define DT2811_ADCSR_ADBUSY BIT(5) /* r 1=A/D busy */
#define DT2811_ADCSR_CLRERROR BIT(4)
-#define DT2811_ADCSR_INTENB BIT(2) /* r/w 1=interupts ena */
+#define DT2811_ADCSR_DMAENB BIT(3) /* r/w 1=dma ena */
+#define DT2811_ADCSR_INTENB BIT(2) /* r/w 1=interupts ena */
#define DT2811_ADCSR_ADMODE(x) (((x) & 0x3) << 0)
-/* single conversion on ADGCR load */
-#define DT2811_ADCSR_ADMODE_SINGLE DT2811_ADCSR_ADMODE(0)
-/* continuous conversion, internal clock, (clock enabled on ADGCR load) */
-#define DT2811_ADCSR_ADMODE_CONT DT2811_ADCSR_ADMODE(1)
-/* continuous conversion, internal clock, external trigger */
-#define DT2811_ADCSR_ADMODE_EXT_TRIG DT2811_ADCSR_ADMODE(2)
-/* continuous conversion, external clock, external trigger */
-#define DT2811_ADCSR_ADMODE_EXT DT2811_ADCSR_ADMODE(3)
#define DT2811_ADGCR_REG 0x01 /* r/w A/D Gain/Channel */
#define DT2811_ADGCR_GAIN(x) (((x) & 0x3) << 6)
#define DT2811_DI_REG 0x06 /* r Digital Input Port 0 */
#define DT2811_DO_REG 0x06 /* w Digital Output Port 1 */
+#define DT2811_TMRCTR_REG 0x07 /* r/w Timer/Counter */
+#define DT2811_TMRCTR_MANTISSA(x) (((x) & 0x7) << 3)
+#define DT2811_TMRCTR_EXPONENT(x) (((x) & 0x7) << 0)
+
+#define DT2811_OSC_BASE 1666 /* 600 kHz = 1666.6667ns */
+
/*
* Timer frequency control:
* DT2811_TMRCTR_MANTISSA DT2811_TMRCTR_EXPONENT
* 6 6 100 kHz 6 1000000
* 7 12 50 kHz 7 10000000
*/
-#define DT2811_TMRCTR_REG 0x07 /* r/w Timer/Counter */
-#define DT2811_TMRCTR_MANTISSA(x) (((x) & 0x7) << 3)
-#define DT2811_TMRCTR_EXPONENT(x) (((x) & 0x7) << 0)
+const unsigned int dt2811_clk_dividers[] = {
+ 1, 10, 2, 3, 4, 5, 6, 12
+};
+
+const unsigned int dt2811_clk_multipliers[] = {
+ 1, 10, 100, 1000, 10000, 100000, 1000000, 10000000
+};
/*
* The Analog Input range is set using jumpers on the board.
},
};
+struct dt2811_private {
+ unsigned int ai_divisor;
+};
+
+static unsigned int dt2811_ai_read_sample(struct comedi_device *dev,
+ struct comedi_subdevice *s)
+{
+ unsigned int val;
+
+ val = inb(dev->iobase + DT2811_ADDATA_LO_REG) |
+ (inb(dev->iobase + DT2811_ADDATA_HI_REG) << 8);
+
+ return val & s->maxdata;
+}
+
+static irqreturn_t dt2811_interrupt(int irq, void *d)
+{
+ struct comedi_device *dev = d;
+ struct comedi_subdevice *s = dev->read_subdev;
+ struct comedi_async *async = s->async;
+ struct comedi_cmd *cmd = &async->cmd;
+ unsigned int status;
+
+ if (!dev->attached)
+ return IRQ_NONE;
+
+ status = inb(dev->iobase + DT2811_ADCSR_REG);
+
+ if (status & DT2811_ADCSR_ADERROR) {
+ async->events |= COMEDI_CB_OVERFLOW;
+
+ outb(status | DT2811_ADCSR_CLRERROR,
+ dev->iobase + DT2811_ADCSR_REG);
+ }
+
+ if (status & DT2811_ADCSR_ADDONE) {
+ unsigned short val;
+
+ val = dt2811_ai_read_sample(dev, s);
+ comedi_buf_write_samples(s, &val, 1);
+ }
+
+ if (cmd->stop_src == TRIG_COUNT && async->scans_done >= cmd->stop_arg)
+ async->events |= COMEDI_CB_EOA;
+
+ comedi_handle_events(dev, s);
+
+ return IRQ_HANDLED;
+}
+
+static int dt2811_ai_cancel(struct comedi_device *dev,
+ struct comedi_subdevice *s)
+{
+ /*
+ * Mode 0
+ * Single conversion
+ *
+ * Loading a chanspec will trigger a conversion.
+ */
+ outb(DT2811_ADCSR_ADMODE(0), dev->iobase + DT2811_ADCSR_REG);
+
+ return 0;
+}
+
+static void dt2811_ai_set_chanspec(struct comedi_device *dev,
+ unsigned int chanspec)
+{
+ unsigned int chan = CR_CHAN(chanspec);
+ unsigned int range = CR_RANGE(chanspec);
+
+ outb(DT2811_ADGCR_CHAN(chan) | DT2811_ADGCR_GAIN(range),
+ dev->iobase + DT2811_ADGCR_REG);
+}
+
+static int dt2811_ai_cmd(struct comedi_device *dev,
+ struct comedi_subdevice *s)
+{
+ struct dt2811_private *devpriv = dev->private;
+ struct comedi_cmd *cmd = &s->async->cmd;
+ unsigned int mode;
+
+ if (cmd->start_src == TRIG_NOW) {
+ /*
+ * Mode 1
+ * Continuous conversion, internal trigger and clock
+ *
+ * This resets the trigger flip-flop, disabling A/D strobes.
+ * The timer/counter register is loaded with the division
+ * ratio which will give the required sample rate.
+ *
+ * Loading the first chanspec sets the trigger flip-flop,
+ * enabling the timer/counter. A/D strobes are then generated
+ * at the rate set by the internal clock/divider.
+ */
+ mode = DT2811_ADCSR_ADMODE(1);
+ } else { /* TRIG_EXT */
+ if (cmd->convert_src == TRIG_TIMER) {
+ /*
+ * Mode 2
+ * Continuous conversion, external trigger
+ *
+ * Similar to Mode 1, with the exception that the
+ * trigger flip-flop must be set by a negative edge
+ * on the external trigger input.
+ */
+ mode = DT2811_ADCSR_ADMODE(2);
+ } else { /* TRIG_EXT */
+ /*
+ * Mode 3
+ * Continuous conversion, external trigger, clock
+ *
+ * Similar to Mode 2, with the exception that the
+ * conversion rate is set by the frequency on the
+ * external clock/divider.
+ */
+ mode = DT2811_ADCSR_ADMODE(3);
+ }
+ }
+ outb(mode | DT2811_ADCSR_INTENB, dev->iobase + DT2811_ADCSR_REG);
+
+ /* load timer */
+ outb(devpriv->ai_divisor, dev->iobase + DT2811_TMRCTR_REG);
+
+ /* load chanspec - enables timer */
+ dt2811_ai_set_chanspec(dev, cmd->chanlist[0]);
+
+ return 0;
+}
+
+static unsigned int dt2811_ns_to_timer(unsigned int *nanosec,
+ unsigned int flags)
+{
+ unsigned long long ns = *nanosec;
+ unsigned int ns_lo = COMEDI_MIN_SPEED;
+ unsigned int ns_hi = 0;
+ unsigned int divisor_hi = 0;
+ unsigned int divisor_lo = 0;
+ unsigned int _div;
+ unsigned int _mult;
+
+ /*
+ * Work through all the divider/multiplier values to find the two
+ * closest divisors to generate the requested nanosecond timing.
+ */
+ for (_div = 0; _div <= 7; _div++) {
+ for (_mult = 0; _mult <= 7; _mult++) {
+ unsigned int div = dt2811_clk_dividers[_div];
+ unsigned int mult = dt2811_clk_multipliers[_mult];
+ unsigned long long divider = div * mult;
+ unsigned int divisor = DT2811_TMRCTR_MANTISSA(_div) |
+ DT2811_TMRCTR_EXPONENT(_mult);
+
+ /*
+ * The timer can be configured to run at a slowest
+ * speed of 0.005hz (600 Khz/120000000), which requires
+ * 37-bits to represent the nanosecond value. Limit the
+ * slowest timing to what comedi handles (32-bits).
+ */
+ ns = divider * DT2811_OSC_BASE;
+ if (ns > COMEDI_MIN_SPEED)
+ continue;
+
+ /* Check for fastest found timing */
+ if (ns <= *nanosec && ns > ns_hi) {
+ ns_hi = ns;
+ divisor_hi = divisor;
+ }
+ /* Check for slowest found timing */
+ if (ns >= *nanosec && ns < ns_lo) {
+ ns_lo = ns;
+ divisor_lo = divisor;
+ }
+ }
+ }
+
+ /*
+ * The slowest found timing will be invalid if the requested timing
+ * is faster than what can be generated by the timer. Fix it so that
+ * CMDF_ROUND_UP returns valid timing.
+ */
+ if (ns_lo == COMEDI_MIN_SPEED) {
+ ns_lo = ns_hi;
+ divisor_lo = divisor_hi;
+ }
+ /*
+ * The fastest found timing will be invalid if the requested timing
+ * is less than what can be generated by the timer. Fix it so that
+ * CMDF_ROUND_NEAREST and CMDF_ROUND_DOWN return valid timing.
+ */
+ if (ns_hi == 0) {
+ ns_hi = ns_lo;
+ divisor_hi = divisor_lo;
+ }
+
+ switch (flags & CMDF_ROUND_MASK) {
+ case CMDF_ROUND_NEAREST:
+ default:
+ if (ns_hi - *nanosec < *nanosec - ns_lo) {
+ *nanosec = ns_lo;
+ return divisor_lo;
+ }
+ *nanosec = ns_hi;
+ return divisor_hi;
+ case CMDF_ROUND_UP:
+ *nanosec = ns_lo;
+ return divisor_lo;
+ case CMDF_ROUND_DOWN:
+ *nanosec = ns_hi;
+ return divisor_hi;
+ }
+}
+
+static int dt2811_ai_cmdtest(struct comedi_device *dev,
+ struct comedi_subdevice *s,
+ struct comedi_cmd *cmd)
+{
+ struct dt2811_private *devpriv = dev->private;
+ unsigned int arg;
+ int err = 0;
+
+ /* Step 1 : check if triggers are trivially valid */
+
+ err |= comedi_check_trigger_src(&cmd->start_src, TRIG_NOW | TRIG_EXT);
+ err |= comedi_check_trigger_src(&cmd->scan_begin_src, TRIG_FOLLOW);
+ err |= comedi_check_trigger_src(&cmd->convert_src,
+ TRIG_TIMER | TRIG_EXT);
+ 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->start_src);
+ err |= comedi_check_trigger_is_unique(cmd->convert_src);
+ err |= comedi_check_trigger_is_unique(cmd->stop_src);
+
+ /* Step 2b : and mutually compatible */
+
+ if (cmd->convert_src == TRIG_EXT && cmd->start_src != TRIG_EXT)
+ err |= -EINVAL;
+
+ 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_is(&cmd->scan_begin_arg, 0);
+ if (cmd->convert_src == TRIG_TIMER)
+ err |= comedi_check_trigger_arg_min(&cmd->convert_arg, 12500);
+ 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, 1);
+ else /* TRIG_NONE */
+ err |= comedi_check_trigger_arg_is(&cmd->stop_arg, 0);
+
+ if (err)
+ return 3;
+
+ /* Step 4: fix up any arguments */
+
+ if (cmd->convert_src == TRIG_TIMER) {
+ arg = cmd->convert_arg;
+ devpriv->ai_divisor = dt2811_ns_to_timer(&arg, cmd->flags);
+ err |= comedi_check_trigger_arg_is(&cmd->convert_arg, arg);
+ } else { /* TRIG_EXT */
+ /* The convert_arg is used to set the divisor. */
+ devpriv->ai_divisor = cmd->convert_arg;
+ }
+
+ if (err)
+ return 4;
+
+ /* Step 5: check channel list if it exists */
+
+ return 0;
+}
+
static int dt2811_ai_eoc(struct comedi_device *dev,
struct comedi_subdevice *s,
struct comedi_insn *insn,
struct comedi_insn *insn,
unsigned int *data)
{
- unsigned int chan = CR_CHAN(insn->chanspec);
- unsigned int range = CR_RANGE(insn->chanspec);
int ret;
int i;
+ /* We will already be in Mode 0 */
for (i = 0; i < insn->n; i++) {
- unsigned int val;
-
- /* select channel/gain and trigger conversion */
- outb(DT2811_ADGCR_CHAN(chan) | DT2811_ADGCR_GAIN(range),
- dev->iobase + DT2811_ADGCR_REG);
+ /* load chanspec and trigger conversion */
+ dt2811_ai_set_chanspec(dev, insn->chanspec);
ret = comedi_timeout(dev, s, insn, dt2811_ai_eoc, 0);
if (ret)
return ret;
- val = inb(dev->iobase + DT2811_ADDATA_LO_REG) |
- (inb(dev->iobase + DT2811_ADDATA_HI_REG) << 8);
- val &= s->maxdata;
-
- data[i] = val;
+ data[i] = dt2811_ai_read_sample(dev, s);
}
- return i;
+ return insn->n;
}
static int dt2811_ao_insn_write(struct comedi_device *dev,
return insn->n;
}
+static void dt2811_reset(struct comedi_device *dev)
+{
+ /* This is the initialization sequence from the users manual */
+ outb(DT2811_ADCSR_ADMODE(0), dev->iobase + DT2811_ADCSR_REG);
+ usleep_range(100, 1000);
+ inb(dev->iobase + DT2811_ADDATA_LO_REG);
+ inb(dev->iobase + DT2811_ADDATA_HI_REG);
+ outb(DT2811_ADCSR_ADMODE(0) | DT2811_ADCSR_CLRERROR,
+ dev->iobase + DT2811_ADCSR_REG);
+}
+
static int dt2811_attach(struct comedi_device *dev, struct comedi_devconfig *it)
{
const struct dt2811_board *board = dev->board_ptr;
+ struct dt2811_private *devpriv;
struct comedi_subdevice *s;
int ret;
+ devpriv = comedi_alloc_devpriv(dev, sizeof(*devpriv));
+ if (!devpriv)
+ return -ENOMEM;
+
ret = comedi_request_region(dev, it->options[0], 0x8);
if (ret)
return ret;
+ dt2811_reset(dev);
+
+ /* IRQ's 2,3,5,7 are valid for async command support */
+ if (it->options[1] <= 7 && (BIT(it->options[1]) & 0xac)) {
+ ret = request_irq(it->options[1], dt2811_interrupt, 0,
+ dev->board_name, dev);
+ if (ret == 0)
+ dev->irq = it->options[1];
+ }
+
ret = comedi_alloc_subdevices(dev, 4);
if (ret)
return ret;
s->range_table = board->is_pgh ? &dt2811_pgh_ai_ranges
: &dt2811_pgl_ai_ranges;
s->insn_read = dt2811_ai_insn_read;
+ if (dev->irq) {
+ dev->read_subdev = s;
+ s->subdev_flags |= SDF_CMD_READ;
+ s->len_chanlist = 1;
+ s->do_cmdtest = dt2811_ai_cmdtest;
+ s->do_cmd = dt2811_ai_cmd;
+ s->cancel = dt2811_ai_cancel;
+ }
/* Analog Output subdevice */
s = &dev->subdevices[1];
projects / platform / kernel / linux-rpi.git / commitdiff