1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * dac02.c 4 * Comedi driver for DAC02 compatible boards 5 * Copyright (C) 2014 H Hartley Sweeten <hsweeten@visionengravers.com> 6 * 7 * Based on the poc driver 8 * Copyright (C) 2000 Frank Mori Hess <fmhess@users.sourceforge.net> 9 * Copyright (C) 2001 David A. Schleef <ds@schleef.org> 10 * 11 * COMEDI - Linux Control and Measurement Device Interface 12 * Copyright (C) 1998 David A. Schleef <ds@schleef.org> 13 */ 14 15 /* 16 * Driver: dac02 17 * Description: Comedi driver for DAC02 compatible boards 18 * Devices: [Keithley Metrabyte] DAC-02 (dac02) 19 * Author: H Hartley Sweeten <hsweeten@visionengravers.com> 20 * Updated: Tue, 11 Mar 2014 11:27:19 -0700 21 * Status: unknown 22 * 23 * Configuration options: 24 * [0] - I/O port base 25 */ 26 27 #include <linux/module.h> 28 29 #include "../comedidev.h" 30 31 /* 32 * The output range is selected by jumpering pins on the I/O connector. 33 * 34 * Range Chan # Jumper pins Output 35 * ------------- ------ ------------- ----------------- 36 * 0 to 5V 0 21 to 22 24 37 * 1 15 to 16 18 38 * 0 to 10V 0 20 to 22 24 39 * 1 14 to 16 18 40 * +/-5V 0 21 to 22 23 41 * 1 15 to 16 17 42 * +/-10V 0 20 to 22 23 43 * 1 14 to 16 17 44 * 4 to 20mA 0 21 to 22 25 45 * 1 15 to 16 19 46 * AC reference 0 In on pin 22 24 (2-quadrant) 47 * In on pin 22 23 (4-quadrant) 48 * 1 In on pin 16 18 (2-quadrant) 49 * In on pin 16 17 (4-quadrant) 50 */ 51 static const struct comedi_lrange das02_ao_ranges = { 52 6, { 53 UNI_RANGE(5), 54 UNI_RANGE(10), 55 BIP_RANGE(5), 56 BIP_RANGE(10), 57 RANGE_mA(4, 20), 58 RANGE_ext(0, 1) 59 } 60 }; 61 62 /* 63 * Register I/O map 64 */ 65 #define DAC02_AO_LSB(x) (0x00 + ((x) * 2)) 66 #define DAC02_AO_MSB(x) (0x01 + ((x) * 2)) 67 68 static int dac02_ao_insn_write(struct comedi_device *dev, 69 struct comedi_subdevice *s, 70 struct comedi_insn *insn, 71 unsigned int *data) 72 { 73 unsigned int chan = CR_CHAN(insn->chanspec); 74 unsigned int range = CR_RANGE(insn->chanspec); 75 unsigned int val; 76 int i; 77 78 for (i = 0; i < insn->n; i++) { 79 val = data[i]; 80 81 s->readback[chan] = val; 82 83 /* 84 * Unipolar outputs are true binary encoding. 85 * Bipolar outputs are complementary offset binary 86 * (that is, 0 = +full scale, maxdata = -full scale). 87 */ 88 if (comedi_range_is_bipolar(s, range)) 89 val = s->maxdata - val; 90 91 /* 92 * DACs are double-buffered. 93 * Write LSB then MSB to latch output. 94 */ 95 outb((val << 4) & 0xf0, dev->iobase + DAC02_AO_LSB(chan)); 96 outb((val >> 4) & 0xff, dev->iobase + DAC02_AO_MSB(chan)); 97 } 98 99 return insn->n; 100 } 101 102 static int dac02_attach(struct comedi_device *dev, struct comedi_devconfig *it) 103 { 104 struct comedi_subdevice *s; 105 int ret; 106 107 ret = comedi_request_region(dev, it->options[0], 0x08); 108 if (ret) 109 return ret; 110 111 ret = comedi_alloc_subdevices(dev, 1); 112 if (ret) 113 return ret; 114 115 /* Analog Output subdevice */ 116 s = &dev->subdevices[0]; 117 s->type = COMEDI_SUBD_AO; 118 s->subdev_flags = SDF_WRITABLE; 119 s->n_chan = 2; 120 s->maxdata = 0x0fff; 121 s->range_table = &das02_ao_ranges; 122 s->insn_write = dac02_ao_insn_write; 123 124 return comedi_alloc_subdev_readback(s); 125 } 126 127 static struct comedi_driver dac02_driver = { 128 .driver_name = "dac02", 129 .module = THIS_MODULE, 130 .attach = dac02_attach, 131 .detach = comedi_legacy_detach, 132 }; 133 module_comedi_driver(dac02_driver); 134 135 MODULE_AUTHOR("H Hartley Sweeten <hsweeten@visionengravers.com>"); 136 MODULE_DESCRIPTION("Comedi driver for DAC02 compatible boards"); 137 MODULE_LICENSE("GPL"); 138