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-rw-r--r--drivers/comedi/drivers/mpc624.c310
1 files changed, 310 insertions, 0 deletions
diff --git a/drivers/comedi/drivers/mpc624.c b/drivers/comedi/drivers/mpc624.c
new file mode 100644
index 000000000..9e51ff528
--- /dev/null
+++ b/drivers/comedi/drivers/mpc624.c
@@ -0,0 +1,310 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * 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>
+ */
+
+/*
+ * 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] - conversion rate
+ * Conversion 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 <linux/module.h>
+#include <linux/comedi/comedidev.h>
+#include <linux/delay.h>
+
+/* 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 BIT(5)
+#define MPC624_ADSDO BIT(4)
+#define MPC624_ADFO BIT(3)
+#define MPC624_ADCS BIT(2)
+#define MPC624_ADSCK BIT(1)
+#define MPC624_ADSDI BIT(0)
+
+/* 32-bit output value bits' names */
+#define MPC624_EOC_BIT BIT(31)
+#define MPC624_DMY_BIT BIT(30)
+#define MPC624_SGN_BIT BIT(29)
+
+/* SDI Speed/Resolution Programming bits */
+#define MPC624_OSR(x) (((x) & 0x1f) << 27)
+#define MPC624_SPEED_3_52_KHZ MPC624_OSR(0x11)
+#define MPC624_SPEED_1_76_KHZ MPC624_OSR(0x12)
+#define MPC624_SPEED_880_HZ MPC624_OSR(0x13)
+#define MPC624_SPEED_440_HZ MPC624_OSR(0x14)
+#define MPC624_SPEED_220_HZ MPC624_OSR(0x15)
+#define MPC624_SPEED_110_HZ MPC624_OSR(0x16)
+#define MPC624_SPEED_55_HZ MPC624_OSR(0x17)
+#define MPC624_SPEED_27_5_HZ MPC624_OSR(0x18)
+#define MPC624_SPEED_13_75_HZ MPC624_OSR(0x19)
+#define MPC624_SPEED_6_875_HZ MPC624_OSR(0x1f)
+
+struct mpc624_private {
+ unsigned int ai_speed;
+};
+
+/* -------------------------------------------------------------------------- */
+static const struct 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 struct 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 unsigned int mpc624_ai_get_sample(struct comedi_device *dev,
+ struct comedi_subdevice *s)
+{
+ struct mpc624_private *devpriv = dev->private;
+ unsigned int data_out = devpriv->ai_speed;
+ unsigned int data_in = 0;
+ unsigned int bit;
+ int i;
+
+ /* Start reading data */
+ udelay(1);
+ for (i = 0; i < 32; i++) {
+ /* Set the clock low */
+ outb(0, dev->iobase + MPC624_ADC);
+ udelay(1);
+
+ /* Set the ADSDI line for the next bit (send to MPC624) */
+ bit = (data_out & BIT(31)) ? MPC624_ADSDI : 0;
+ outb(bit, dev->iobase + MPC624_ADC);
+ udelay(1);
+
+ /* Set the clock high */
+ outb(MPC624_ADSCK | bit, dev->iobase + MPC624_ADC);
+ udelay(1);
+
+ /* Read ADSDO on high clock (receive from MPC624) */
+ data_in <<= 1;
+ data_in |= (inb(dev->iobase + MPC624_ADC) & MPC624_ADSDO) >> 4;
+ 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 positive, 0 if negative
+ * 28: MSB - (Most Significant Bit) - the first bit of the
+ * conversion result
+ * ....
+ * 05: LSB - (Least Significant Bit)- the last bit of the
+ * conversion result
+ * 04-00: sub-LSB - sub-LSBs are basically noise, but when
+ * averaged properly, they can increase
+ * conversion precision up to 29 bits;
+ * they can be discarded without loss of
+ * resolution.
+ */
+ if (data_in & MPC624_EOC_BIT)
+ dev_dbg(dev->class_dev, "EOC bit is set!");
+ if (data_in & MPC624_DMY_BIT)
+ dev_dbg(dev->class_dev, "DMY bit is set!");
+
+ if (data_in & MPC624_SGN_BIT) {
+ /*
+ * Voltage is positive
+ *
+ * comedi operates on unsigned numbers, so mask off EOC
+ * and DMY and don't clear the SGN bit
+ */
+ data_in &= 0x3fffffff;
+ } 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;
+ /* clear EOC and DMY bits */
+ data_in &= ~(MPC624_EOC_BIT | MPC624_DMY_BIT);
+ data_in = 0x20000000 - data_in;
+ }
+ return data_in;
+}
+
+static int mpc624_ai_eoc(struct comedi_device *dev,
+ struct comedi_subdevice *s,
+ struct comedi_insn *insn,
+ unsigned long context)
+{
+ unsigned char status;
+
+ status = inb(dev->iobase + MPC624_ADC);
+ if ((status & MPC624_ADBUSY) == 0)
+ return 0;
+ return -EBUSY;
+}
+
+static int mpc624_ai_insn_read(struct comedi_device *dev,
+ struct comedi_subdevice *s,
+ struct comedi_insn *insn,
+ unsigned int *data)
+{
+ int ret;
+ int i;
+
+ /*
+ * WARNING:
+ * We always write 0 to GNSWA bit, so the channel range is +-/10.1Vdc
+ */
+ outb(insn->chanspec, dev->iobase + MPC624_GNMUXCH);
+
+ for (i = 0; i < insn->n; i++) {
+ /* Trigger the conversion */
+ outb(MPC624_ADSCK, dev->iobase + MPC624_ADC);
+ udelay(1);
+ outb(MPC624_ADCS | MPC624_ADSCK, dev->iobase + MPC624_ADC);
+ udelay(1);
+ outb(0, dev->iobase + MPC624_ADC);
+ udelay(1);
+
+ /* Wait for the conversion to end */
+ ret = comedi_timeout(dev, s, insn, mpc624_ai_eoc, 0);
+ if (ret)
+ return ret;
+
+ data[i] = mpc624_ai_get_sample(dev, s);
+ }
+
+ return insn->n;
+}
+
+static int mpc624_attach(struct comedi_device *dev, struct comedi_devconfig *it)
+{
+ struct mpc624_private *devpriv;
+ struct comedi_subdevice *s;
+ int ret;
+
+ ret = comedi_request_region(dev, it->options[0], 0x10);
+ if (ret)
+ return ret;
+
+ devpriv = comedi_alloc_devpriv(dev, sizeof(*devpriv));
+ if (!devpriv)
+ return -ENOMEM;
+
+ switch (it->options[1]) {
+ case 0:
+ devpriv->ai_speed = MPC624_SPEED_3_52_KHZ;
+ break;
+ case 1:
+ devpriv->ai_speed = MPC624_SPEED_1_76_KHZ;
+ break;
+ case 2:
+ devpriv->ai_speed = MPC624_SPEED_880_HZ;
+ break;
+ case 3:
+ devpriv->ai_speed = MPC624_SPEED_440_HZ;
+ break;
+ case 4:
+ devpriv->ai_speed = MPC624_SPEED_220_HZ;
+ break;
+ case 5:
+ devpriv->ai_speed = MPC624_SPEED_110_HZ;
+ break;
+ case 6:
+ devpriv->ai_speed = MPC624_SPEED_55_HZ;
+ break;
+ case 7:
+ devpriv->ai_speed = MPC624_SPEED_27_5_HZ;
+ break;
+ case 8:
+ devpriv->ai_speed = MPC624_SPEED_13_75_HZ;
+ break;
+ case 9:
+ devpriv->ai_speed = MPC624_SPEED_6_875_HZ;
+ break;
+ default:
+ devpriv->ai_speed = MPC624_SPEED_3_52_KHZ;
+ }
+
+ ret = comedi_alloc_subdevices(dev, 1);
+ if (ret)
+ return ret;
+
+ /* Analog Input subdevice */
+ s = &dev->subdevices[0];
+ s->type = COMEDI_SUBD_AI;
+ s->subdev_flags = SDF_READABLE | SDF_DIFF;
+ s->n_chan = 4;
+ s->maxdata = 0x3fffffff;
+ s->range_table = (it->options[1] == 0) ? &range_mpc624_bipolar1
+ : &range_mpc624_bipolar10;
+ s->insn_read = mpc624_ai_insn_read;
+
+ return 0;
+}
+
+static struct comedi_driver mpc624_driver = {
+ .driver_name = "mpc624",
+ .module = THIS_MODULE,
+ .attach = mpc624_attach,
+ .detach = comedi_legacy_detach,
+};
+module_comedi_driver(mpc624_driver);
+
+MODULE_AUTHOR("Comedi https://www.comedi.org");
+MODULE_DESCRIPTION("Comedi driver for Micro/sys MPC-624 PC/104 board");
+MODULE_LICENSE("GPL");
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-07 06:25:30 +0000