Staging: comedi: add mpc624 driver

driver for a Micro/sys inc. MPC-624 PC/104 board

From: Stanislaw Raczynski <sraczynski@op.pl>
Cc: David Schleef <ds@schleef.org>
Cc: Frank Mori Hess <fmhess@users.sourceforge.net>
Cc: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/comedi/drivers/mpc624.c

+/*
+    comedi/drivers/mpc624.c
+    Hardware driver for a Micro/sys inc. MPC-624 PC/104 board
+
+    COMEDI - Linux Control and Measurement Device Interface
+    Copyright (C) 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.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+*/
+/*
+Driver: mpc624
+Description: Micro/sys MPC-624 PC/104 board
+Devices: [Micro/sys] MPC-624 (mpc624)
+Author: Stanislaw Raczynski <sraczynski@op.pl>
+Updated: Thu, 15 Sep 2005 12:01:18 +0200
+Status: working
+
+    The Micro/sys MPC-624 board is based on the LTC2440 24-bit sigma-delta
+    ADC chip.
+
+    Subdevices supported by the driver:
+    - Analog In:   supported
+    - Digital I/O: not supported
+    - LEDs:        not supported
+    - EEPROM:      not supported
+
+Configuration Options:
+  [0] - I/O base address
+  [1] - convertion rate
+            Convertion rate  RMS noise  Effective Number Of Bits
+         0      3.52kHz        23uV                17
+         1      1.76kHz       3.5uV                20
+         2       880Hz         2uV                21.3
+         3       440Hz        1.4uV               21.8
+         4       220Hz         1uV                22.4
+         5       110Hz        750uV               22.9
+         6       55Hz         510nV               23.4
+         7      27.5Hz        375nV                24
+         8      13.75Hz       250nV               24.4
+         9      6.875Hz       200nV               24.6
+   [2] - voltage range
+         0      -1.01V .. +1.01V
+         1      -10.1V .. +10.1V
+*/
+
+#include "../comedidev.h"
+
+#include <linux/ioport.h>
+#include <linux/delay.h>
+
+// Consecutive I/O port addresses
+#define MPC624_SIZE             16
+
+// Offsets of different ports
+#define MPC624_MASTER_CONTROL	0	// not used
+#define MPC624_GNMUXCH          1	// Gain, Mux, Channel of ADC
+#define MPC624_ADC              2	// read/write to/from ADC
+#define MPC624_EE               3	// read/write to/from serial EEPROM via I2C
+#define MPC624_LEDS             4	// write to LEDs
+#define MPC624_DIO              5	// read/write to/from digital I/O ports
+#define MPC624_IRQ_MASK         6	// IRQ masking enable/disable
+
+// Register bits' names
+#define MPC624_ADBUSY           (1<<5)
+#define MPC624_ADSDO            (1<<4)
+#define MPC624_ADFO             (1<<3)
+#define MPC624_ADCS             (1<<2)
+#define MPC624_ADSCK            (1<<1)
+#define MPC624_ADSDI            (1<<0)
+
+// SDI Speed/Resolution Programming bits
+#define MPC624_OSR4             (1<<31)
+#define MPC624_OSR3             (1<<30)
+#define MPC624_OSR2             (1<<29)
+#define MPC624_OSR1             (1<<28)
+#define MPC624_OSR0             (1<<27)
+
+// 32-bit output value bits' names
+#define MPC624_EOC_BIT          (1<<31)
+#define MPC624_DMY_BIT          (1<<30)
+#define MPC624_SGN_BIT          (1<<29)
+
+// Convertion speeds
+/* OSR4 OSR3 OSR2 OSR1 OSR0  Convertion rate  RMS noise  ENOB^
+ *  X    0    0    0    1        3.52kHz        23uV      17
+ *  X    0    0    1    0        1.76kHz       3.5uV      20
+ *  X    0    0    1    1         880Hz         2uV      21.3
+ *  X    0    1    0    0         440Hz        1.4uV     21.8
+ *  X    0    1    0    1         220Hz         1uV      22.4
+ *  X    0    1    1    0         110Hz        750uV     22.9
+ *  X    0    1    1    1          55Hz        510nV     23.4
+ *  X    1    0    0    0         27.5Hz       375nV      24
+ *  X    1    0    0    1        13.75Hz       250nV     24.4
+ *  X    1    1    1    1        6.875Hz       200nV     24.6
+ *
+ * ^ - Effective Number Of Bits
+ */
+
+#define MPC624_SPEED_3_52_kHz   (MPC624_OSR4                                           | MPC624_OSR0)
+#define MPC624_SPEED_1_76_kHz   (MPC624_OSR4                             | MPC624_OSR1              )
+#define MPC624_SPEED_880_Hz     (MPC624_OSR4                             | MPC624_OSR1 | MPC624_OSR0)
+#define MPC624_SPEED_440_Hz     (MPC624_OSR4               | MPC624_OSR2                            )
+#define MPC624_SPEED_220_Hz     (MPC624_OSR4               | MPC624_OSR2               | MPC624_OSR0)
+#define MPC624_SPEED_110_Hz     (MPC624_OSR4               | MPC624_OSR2 | MPC624_OSR1              )
+#define MPC624_SPEED_55_Hz      (MPC624_OSR4               | MPC624_OSR2 | MPC624_OSR1 | MPC624_OSR0)
+#define MPC624_SPEED_27_5_Hz    (MPC624_OSR4 | MPC624_OSR3                                          )
+#define MPC624_SPEED_13_75_Hz   (MPC624_OSR4 | MPC624_OSR3                             | MPC624_OSR0)
+#define MPC624_SPEED_6_875_Hz   (MPC624_OSR4 | MPC624_OSR3 | MPC624_OSR2 | MPC624_OSR1 | MPC624_OSR0)
+//----------------------------------------------------------------------------
+typedef struct {
+	unsigned long int ulConvertionRate;	// set by mpc624_attach() from driver's parameters
+} skel_private;
+
+#define devpriv ((skel_private *)dev->private)
+//----------------------------------------------------------------------------
+static const comedi_lrange range_mpc624_bipolar1 = {
+	1,
+	{
+//    BIP_RANGE(1.01) // this is correct,
+			// but my MPC-624 actually seems to have a range of 2.02
+			BIP_RANGE(2.02)
+		}
+};
+static const comedi_lrange range_mpc624_bipolar10 = {
+	1,
+	{
+//    BIP_RANGE(10.1) // this is correct,
+			// but my MPC-624 actually seems to have a range of 20.2
+			BIP_RANGE(20.2)
+		}
+};
+
+//----------------------------------------------------------------------------
+static int mpc624_attach(comedi_device * dev, comedi_devconfig * it);
+static int mpc624_detach(comedi_device * dev);
+//----------------------------------------------------------------------------
+static comedi_driver driver_mpc624 = {
+      driver_name:"mpc624",
+      module:THIS_MODULE,
+      attach:mpc624_attach,
+      detach:mpc624_detach
+};
+
+//----------------------------------------------------------------------------
+static int mpc624_ai_rinsn(comedi_device * dev, comedi_subdevice * s,
+	comedi_insn * insn, lsampl_t * data);
+//----------------------------------------------------------------------------
+static int mpc624_attach(comedi_device * dev, comedi_devconfig * it)
+{
+	comedi_subdevice *s;
+	unsigned long iobase;
+
+	iobase = it->options[0];
+	rt_printk("comedi%d: mpc624 [0x%04lx, ", dev->minor, iobase);
+	if (request_region(iobase, MPC624_SIZE, "mpc624") == NULL) {
+		rt_printk("I/O port(s) in use\n");
+		return -EIO;
+	}
+
+	dev->iobase = iobase;
+	dev->board_name = "mpc624";
+
+	// Private structure initialization
+	if (alloc_private(dev, sizeof(skel_private)) < 0)
+		return -ENOMEM;
+
+	switch (it->options[1]) {
+	case 0:
+		devpriv->ulConvertionRate = MPC624_SPEED_3_52_kHz;
+		rt_printk("3.52 kHz, ");
+		break;
+	case 1:
+		devpriv->ulConvertionRate = MPC624_SPEED_1_76_kHz;
+		rt_printk("1.76 kHz, ");
+		break;
+	case 2:
+		devpriv->ulConvertionRate = MPC624_SPEED_880_Hz;
+		rt_printk("880 Hz, ");
+		break;
+	case 3:
+		devpriv->ulConvertionRate = MPC624_SPEED_440_Hz;
+		rt_printk("440 Hz, ");
+		break;
+	case 4:
+		devpriv->ulConvertionRate = MPC624_SPEED_220_Hz;
+		rt_printk("220 Hz, ");
+		break;
+	case 5:
+		devpriv->ulConvertionRate = MPC624_SPEED_110_Hz;
+		rt_printk("110 Hz, ");
+		break;
+	case 6:
+		devpriv->ulConvertionRate = MPC624_SPEED_55_Hz;
+		rt_printk("55 Hz, ");
+		break;
+	case 7:
+		devpriv->ulConvertionRate = MPC624_SPEED_27_5_Hz;
+		rt_printk("27.5 Hz, ");
+		break;
+	case 8:
+		devpriv->ulConvertionRate = MPC624_SPEED_13_75_Hz;
+		rt_printk("13.75 Hz, ");
+		break;
+	case 9:
+		devpriv->ulConvertionRate = MPC624_SPEED_6_875_Hz;
+		rt_printk("6.875 Hz, ");
+		break;
+	default:
+		rt_printk
+			("illegal convertion rate setting! Valid numbers are 0..9. Using 9 => 6.875 Hz, ");
+		devpriv->ulConvertionRate = MPC624_SPEED_3_52_kHz;
+	}
+
+	// Subdevices structures
+	if (alloc_subdevices(dev, 1) < 0)
+		return -ENOMEM;
+
+	s = dev->subdevices + 0;
+	s->type = COMEDI_SUBD_AI;
+	s->subdev_flags = SDF_READABLE | SDF_DIFF;
+	s->n_chan = 8;
+	switch (it->options[1]) {
+	default:
+		s->maxdata = 0x3FFFFFFF;
+		rt_printk("30 bit, ");
+	}
+
+	switch (it->options[1]) {
+	case 0:
+		s->range_table = &range_mpc624_bipolar1;
+		rt_printk("1.01V]: ");
+		break;
+	default:
+		s->range_table = &range_mpc624_bipolar10;
+		rt_printk("10.1V]: ");
+	}
+	s->len_chanlist = 1;
+	s->insn_read = mpc624_ai_rinsn;
+
+	rt_printk("attached\n");
+
+	return 1;
+}
+
+static int mpc624_detach(comedi_device * dev)
+{
+	rt_printk("comedi%d: mpc624: remove\n", dev->minor);
+
+	if (dev->iobase)
+		release_region(dev->iobase, MPC624_SIZE);
+
+	return 0;
+}
+
+// Timeout 200ms
+#define TIMEOUT 200
+
+static int mpc624_ai_rinsn(comedi_device * dev, comedi_subdevice * s,
+	comedi_insn * insn, lsampl_t * data)
+{
+	int n, i;
+	unsigned long int data_in, data_out;
+	unsigned char ucPort;
+
+	// WARNING: We always write 0 to GNSWA bit, so the channel range is +-/10.1Vdc
+	outb(insn->chanspec, dev->iobase + MPC624_GNMUXCH);
+//    rt_printk("Channel %d: \n", insn->chanspec);
+	if (!insn->n) {
+		rt_printk("MPC624: Warning, no data to aquire\n");
+		return 0;
+	}
+
+	for (n = 0; n < insn->n; n++) {
+		// Trigger the convertion
+		outb(MPC624_ADSCK, dev->iobase + MPC624_ADC);
+		comedi_udelay(1);
+		outb(MPC624_ADCS | MPC624_ADSCK, dev->iobase + MPC624_ADC);
+		comedi_udelay(1);
+		outb(0, dev->iobase + MPC624_ADC);
+		comedi_udelay(1);
+
+		// Wait for the convertion to end
+		for (i = 0; i < TIMEOUT; i++) {
+			ucPort = inb(dev->iobase + MPC624_ADC);
+			if (ucPort & MPC624_ADBUSY)
+				comedi_udelay(1000);
+			else
+				break;
+		}
+		if (i == TIMEOUT) {
+			rt_printk("MPC624: timeout (%dms)\n", TIMEOUT);
+			data[n] = 0;
+			return -ETIMEDOUT;
+		}
+		// Start reading data
+		data_in = 0;
+		data_out = devpriv->ulConvertionRate;
+		comedi_udelay(1);
+		for (i = 0; i < 32; i++) {
+			// Set the clock low
+			outb(0, dev->iobase + MPC624_ADC);
+			comedi_udelay(1);
+
+			if (data_out & (1 << 31))	// the next bit is a 1
+			{
+				// Set the ADSDI line (send to MPC624)
+				outb(MPC624_ADSDI, dev->iobase + MPC624_ADC);
+				comedi_udelay(1);
+				// Set the clock high
+				outb(MPC624_ADSCK | MPC624_ADSDI,
+					dev->iobase + MPC624_ADC);
+			} else	// the next bit is a 0
+			{
+				// Set the ADSDI line (send to MPC624)
+				outb(0, dev->iobase + MPC624_ADC);
+				comedi_udelay(1);
+				// Set the clock high
+				outb(MPC624_ADSCK, dev->iobase + MPC624_ADC);
+			}
+			// Read ADSDO on high clock (receive from MPC624)
+			comedi_udelay(1);
+			data_in <<= 1;
+			data_in |=
+				(inb(dev->iobase +
+					MPC624_ADC) & MPC624_ADSDO) >> 4;
+			comedi_udelay(1);
+
+			data_out <<= 1;
+		}
+
+		// Received 32-bit long value consist of:
+		//   31: EOC (End Of Transmission) bit - should be 0
+		//   30: DMY (Dummy) bit               - should be 0
+		//   29: SIG (Sign) bit                - 1 if the voltage is positive, 0 if negative
+		//   28: MSB (Most Significant Bit)    - the first bit of convertion result
+		//   ....
+		//   05: LSB (Least Significant Bit)   - the last bit of convertion result
+		//   04: sub-LSB                       - sub-LSBs are basically noise, but when
+		//   03: sub-LSB                         averaged properly, they can increase convertion
+		//   02: sub-LSB                         precision up to 29 bits; they can be discarded
+		//   01: sub-LSB                         without loss of resolution.
+		//   00: sub-LSB
+
+		if (data_in & MPC624_EOC_BIT)
+			rt_printk("MPC624: EOC bit is set (data_in=%lu)!",
+				data_in);
+		if (data_in & MPC624_DMY_BIT)
+			rt_printk("MPC624: DMY bit is set (data_in=%lu)!",
+				data_in);
+		if (data_in & MPC624_SGN_BIT)	// check the sign bit
+		{		// The voltage is positive
+			data_in &= 0x3FFFFFFF;	// EOC and DMY should be 0, but we will mask them out just to be sure
+			data[n] = data_in;	// comedi operates on unsigned numbers, so we don't clear the SGN bit
+			// SGN bit is still set! It's correct, since we're converting to unsigned.
+		} else {	// The voltage is negative
+			// data_in contains a number in 30-bit two's complement code and we must deal with it
+			data_in |= MPC624_SGN_BIT;
+			data_in = ~data_in;
+			data_in += 1;
+			data_in &= ~(MPC624_EOC_BIT | MPC624_DMY_BIT);
+			// clear EOC and DMY bits
+			data_in = 0x20000000 - data_in;
+			data[n] = data_in;
+		}
+	}
+
+	// Return the number of samples read/written
+	return n;
+}
+
+COMEDI_INITCLEANUP(driver_mpc624);