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