// SPDX-License-Identifier: GPL-2.0+ /* * comedi_parport.c * Comedi driver for standard parallel port * * For more information see: * http://retired.beyondlogic.org/spp/parallel.htm * * COMEDI - Linux Control and Measurement Device Interface * Copyright (C) 1998,2001 David A. Schleef */ /* * Driver: comedi_parport * Description: Standard PC parallel port * Author: ds * Status: works in immediate mode * Devices: [standard] parallel port (comedi_parport) * Updated: Tue, 30 Apr 2002 21:11:45 -0700 * * A cheap and easy way to get a few more digital I/O lines. Steal * additional parallel ports from old computers or your neighbors' * computers. * * Option list: * 0: I/O port base for the parallel port. * 1: IRQ (optional) * * Parallel Port Lines: * * pin subdev chan type name * ----- ------ ---- ---- -------------- * 1 2 0 DO strobe * 2 0 0 DIO data 0 * 3 0 1 DIO data 1 * 4 0 2 DIO data 2 * 5 0 3 DIO data 3 * 6 0 4 DIO data 4 * 7 0 5 DIO data 5 * 8 0 6 DIO data 6 * 9 0 7 DIO data 7 * 10 1 3 DI ack * 11 1 4 DI busy * 12 1 2 DI paper out * 13 1 1 DI select in * 14 2 1 DO auto LF * 15 1 0 DI error * 16 2 2 DO init * 17 2 3 DO select printer * 18-25 ground * * When an IRQ is configured subdevice 3 pretends to be a digital * input subdevice, but it always returns 0 when read. However, if * you run a command with scan_begin_src=TRIG_EXT, it uses pin 10 * as a external trigger, which can be used to wake up tasks. */ #include #include #include "../comedidev.h" /* * Register map */ #define PARPORT_DATA_REG 0x00 #define PARPORT_STATUS_REG 0x01 #define PARPORT_CTRL_REG 0x02 #define PARPORT_CTRL_IRQ_ENA BIT(4) #define PARPORT_CTRL_BIDIR_ENA BIT(5) static int parport_data_reg_insn_bits(struct comedi_device *dev, struct comedi_subdevice *s, struct comedi_insn *insn, unsigned int *data) { if (comedi_dio_update_state(s, data)) outb(s->state, dev->iobase + PARPORT_DATA_REG); data[1] = inb(dev->iobase + PARPORT_DATA_REG); return insn->n; } static int parport_data_reg_insn_config(struct comedi_device *dev, struct comedi_subdevice *s, struct comedi_insn *insn, unsigned int *data) { unsigned int ctrl; int ret; ret = comedi_dio_insn_config(dev, s, insn, data, 0xff); if (ret) return ret; ctrl = inb(dev->iobase + PARPORT_CTRL_REG); if (s->io_bits) ctrl &= ~PARPORT_CTRL_BIDIR_ENA; else ctrl |= PARPORT_CTRL_BIDIR_ENA; outb(ctrl, dev->iobase + PARPORT_CTRL_REG); return insn->n; } static int parport_status_reg_insn_bits(struct comedi_device *dev, struct comedi_subdevice *s, struct comedi_insn *insn, unsigned int *data) { data[1] = inb(dev->iobase + PARPORT_STATUS_REG) >> 3; return insn->n; } static int parport_ctrl_reg_insn_bits(struct comedi_device *dev, struct comedi_subdevice *s, struct comedi_insn *insn, unsigned int *data) { unsigned int ctrl; if (comedi_dio_update_state(s, data)) { ctrl = inb(dev->iobase + PARPORT_CTRL_REG); ctrl &= (PARPORT_CTRL_IRQ_ENA | PARPORT_CTRL_BIDIR_ENA); ctrl |= s->state; outb(ctrl, dev->iobase + PARPORT_CTRL_REG); } data[1] = s->state; return insn->n; } static int parport_intr_insn_bits(struct comedi_device *dev, struct comedi_subdevice *s, struct comedi_insn *insn, unsigned int *data) { data[1] = 0; return insn->n; } static int parport_intr_cmdtest(struct comedi_device *dev, struct comedi_subdevice *s, struct comedi_cmd *cmd) { int err = 0; /* Step 1 : check if triggers are trivially valid */ err |= comedi_check_trigger_src(&cmd->start_src, TRIG_NOW); err |= comedi_check_trigger_src(&cmd->scan_begin_src, TRIG_EXT); err |= comedi_check_trigger_src(&cmd->convert_src, TRIG_FOLLOW); err |= comedi_check_trigger_src(&cmd->scan_end_src, TRIG_COUNT); err |= comedi_check_trigger_src(&cmd->stop_src, TRIG_NONE); if (err) return 1; /* Step 2a : make sure trigger sources are unique */ /* Step 2b : and mutually compatible */ /* 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); err |= comedi_check_trigger_arg_is(&cmd->convert_arg, 0); err |= comedi_check_trigger_arg_is(&cmd->scan_end_arg, cmd->chanlist_len); err |= comedi_check_trigger_arg_is(&cmd->stop_arg, 0); if (err) return 3; /* Step 4: fix up any arguments */ /* Step 5: check channel list if it exists */ return 0; } static int parport_intr_cmd(struct comedi_device *dev, struct comedi_subdevice *s) { unsigned int ctrl; ctrl = inb(dev->iobase + PARPORT_CTRL_REG); ctrl |= PARPORT_CTRL_IRQ_ENA; outb(ctrl, dev->iobase + PARPORT_CTRL_REG); return 0; } static int parport_intr_cancel(struct comedi_device *dev, struct comedi_subdevice *s) { unsigned int ctrl; ctrl = inb(dev->iobase + PARPORT_CTRL_REG); ctrl &= ~PARPORT_CTRL_IRQ_ENA; outb(ctrl, dev->iobase + PARPORT_CTRL_REG); return 0; } static irqreturn_t parport_interrupt(int irq, void *d) { struct comedi_device *dev = d; struct comedi_subdevice *s = dev->read_subdev; unsigned int ctrl; ctrl = inb(dev->iobase + PARPORT_CTRL_REG); if (!(ctrl & PARPORT_CTRL_IRQ_ENA)) return IRQ_NONE; comedi_buf_write_samples(s, &s->state, 1); comedi_handle_events(dev, s); return IRQ_HANDLED; } static int parport_attach(struct comedi_device *dev, struct comedi_devconfig *it) { struct comedi_subdevice *s; int ret; ret = comedi_request_region(dev, it->options[0], 0x03); if (ret) return ret; if (it->options[1]) { ret = request_irq(it->options[1], parport_interrupt, 0, dev->board_name, dev); if (ret == 0) dev->irq = it->options[1]; } ret = comedi_alloc_subdevices(dev, dev->irq ? 4 : 3); if (ret) return ret; /* Digial I/O subdevice - Parallel port DATA register */ s = &dev->subdevices[0]; s->type = COMEDI_SUBD_DIO; s->subdev_flags = SDF_READABLE | SDF_WRITABLE; s->n_chan = 8; s->maxdata = 1; s->range_table = &range_digital; s->insn_bits = parport_data_reg_insn_bits; s->insn_config = parport_data_reg_insn_config; /* Digial Input subdevice - Parallel port STATUS register */ s = &dev->subdevices[1]; s->type = COMEDI_SUBD_DI; s->subdev_flags = SDF_READABLE; s->n_chan = 5; s->maxdata = 1; s->range_table = &range_digital; s->insn_bits = parport_status_reg_insn_bits; /* Digial Output subdevice - Parallel port CONTROL register */ s = &dev->subdevices[2]; s->type = COMEDI_SUBD_DO; s->subdev_flags = SDF_WRITABLE; s->n_chan = 4; s->maxdata = 1; s->range_table = &range_digital; s->insn_bits = parport_ctrl_reg_insn_bits; if (dev->irq) { /* Digial Input subdevice - Interrupt support */ s = &dev->subdevices[3]; dev->read_subdev = s; s->type = COMEDI_SUBD_DI; s->subdev_flags = SDF_READABLE | SDF_CMD_READ; s->n_chan = 1; s->maxdata = 1; s->range_table = &range_digital; s->insn_bits = parport_intr_insn_bits; s->len_chanlist = 1; s->do_cmdtest = parport_intr_cmdtest; s->do_cmd = parport_intr_cmd; s->cancel = parport_intr_cancel; } outb(0, dev->iobase + PARPORT_DATA_REG); outb(0, dev->iobase + PARPORT_CTRL_REG); return 0; } static struct comedi_driver parport_driver = { .driver_name = "comedi_parport", .module = THIS_MODULE, .attach = parport_attach, .detach = comedi_legacy_detach, }; module_comedi_driver(parport_driver); MODULE_AUTHOR("Comedi http://www.comedi.org"); MODULE_DESCRIPTION("Comedi: Standard parallel port driver"); MODULE_LICENSE("GPL");