Staging: comedi: add amplc_pc236 driver

for Amplicon PC36AT and PCI236 devices

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

drivers/staging/comedi/drivers/amplc_pc236.c

+/*
+    comedi/drivers/amplc_pc236.c
+    Driver for Amplicon PC36AT and PCI236 DIO boards.
+
+    Copyright (C) 2002 MEV Ltd. <http://www.mev.co.uk/>
+
+    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: amplc_pc236
+Description: Amplicon PC36AT, PCI236
+Author: Ian Abbott <abbotti@mev.co.uk>
+Devices: [Amplicon] PC36AT (pc36at), PCI236 (pci236 or amplc_pc236)
+Updated: Wed, 22 Oct 2008 13:40:03 +0100
+Status: works
+
+Configuration options - PC36AT:
+  [0] - I/O port base address
+  [1] - IRQ (optional)
+
+Configuration options - PCI236:
+  [0] - PCI bus of device (optional)
+  [1] - PCI slot of device (optional)
+  If bus/slot is not specified, the first available PCI device will be
+  used.
+
+The PC36AT ISA board and PCI236 PCI board have a single 8255 appearing
+as subdevice 0.
+
+Subdevice 1 pretends to be a digital input device, but it always returns
+0 when read. However, if you run a command with scan_begin_src=TRIG_EXT,
+a rising edge on port C bit 7 acts as an external trigger, which can be
+used to wake up tasks.  This is like the comedi_parport device, but the
+only way to physically disable the interrupt on the PC36AT is to remove
+the IRQ jumper.  If no interrupt is connected, then subdevice 1 is
+unused.
+*/
+
+#include "../comedidev.h"
+
+#include "comedi_pci.h"
+
+#include "8255.h"
+#include "plx9052.h"
+
+#define PC236_DRIVER_NAME	"amplc_pc236"
+
+/* PCI236 PCI configuration register information */
+#define PCI_VENDOR_ID_AMPLICON 0x14dc
+#define PCI_DEVICE_ID_AMPLICON_PCI236 0x0009
+#define PCI_DEVICE_ID_INVALID 0xffff
+
+/* PC36AT / PCI236 registers */
+
+#define PC236_IO_SIZE		4
+#define PC236_LCR_IO_SIZE	128
+
+/*
+ * INTCSR values for PCI236.
+ */
+/* Disable interrupt, also clear any interrupt there */
+#define PCI236_INTR_DISABLE ( PLX9052_INTCSR_LI1ENAB_DISABLED \
+        | PLX9052_INTCSR_LI1POL_HIGH \
+        | PLX9052_INTCSR_LI2POL_HIGH \
+        | PLX9052_INTCSR_PCIENAB_DISABLED \
+        | PLX9052_INTCSR_LI1SEL_EDGE \
+        | PLX9052_INTCSR_LI1CLRINT_ASSERTED )
+/* Enable interrupt, also clear any interrupt there. */
+#define PCI236_INTR_ENABLE ( PLX9052_INTCSR_LI1ENAB_ENABLED \
+        | PLX9052_INTCSR_LI1POL_HIGH \
+        | PLX9052_INTCSR_LI2POL_HIGH \
+        | PLX9052_INTCSR_PCIENAB_ENABLED \
+        | PLX9052_INTCSR_LI1SEL_EDGE \
+        | PLX9052_INTCSR_LI1CLRINT_ASSERTED )
+
+/*
+ * Board descriptions for Amplicon PC36AT and PCI236.
+ */
+
+enum pc236_bustype { isa_bustype, pci_bustype };
+enum pc236_model { pc36at_model, pci236_model, anypci_model };
+
+typedef struct pc236_board_struct {
+	const char *name;
+	const char *fancy_name;
+	unsigned short devid;
+	enum pc236_bustype bustype;
+	enum pc236_model model;
+} pc236_board;
+static const pc236_board pc236_boards[] = {
+	{
+	      name:	"pc36at",
+	      fancy_name:"PC36AT",
+	      bustype:	isa_bustype,
+	      model:	pc36at_model,
+		},
+#ifdef CONFIG_COMEDI_PCI
+	{
+	      name:	"pci236",
+	      fancy_name:"PCI236",
+	      devid:	PCI_DEVICE_ID_AMPLICON_PCI236,
+	      bustype:	pci_bustype,
+	      model:	pci236_model,
+		},
+#endif
+#ifdef CONFIG_COMEDI_PCI
+	{
+	      name:	PC236_DRIVER_NAME,
+	      fancy_name:PC236_DRIVER_NAME,
+	      devid:	PCI_DEVICE_ID_INVALID,
+	      bustype:	pci_bustype,
+	      model:	anypci_model,	/* wildcard */
+		},
+#endif
+};
+
+#ifdef CONFIG_COMEDI_PCI
+static DEFINE_PCI_DEVICE_TABLE(pc236_pci_table) = {
+	{PCI_VENDOR_ID_AMPLICON, PCI_DEVICE_ID_AMPLICON_PCI236, PCI_ANY_ID,
+		PCI_ANY_ID, 0, 0, 0},
+	{0}
+};
+
+MODULE_DEVICE_TABLE(pci, pc236_pci_table);
+#endif /* CONFIG_COMEDI_PCI */
+
+/*
+ * Useful for shorthand access to the particular board structure
+ */
+#define thisboard ((const pc236_board *)dev->board_ptr)
+
+/* this structure is for data unique to this hardware driver.  If
+   several hardware drivers keep similar information in this structure,
+   feel free to suggest moving the variable to the comedi_device struct.  */
+typedef struct {
+#ifdef CONFIG_COMEDI_PCI
+	/* PCI device */
+	struct pci_dev *pci_dev;
+	unsigned long lcr_iobase;	/* PLX PCI9052 config registers in PCIBAR1 */
+#endif
+	int enable_irq;
+} pc236_private;
+
+#define devpriv ((pc236_private *)dev->private)
+
+/*
+ * The comedi_driver structure tells the Comedi core module
+ * which functions to call to configure/deconfigure (attach/detach)
+ * the board, and also about the kernel module that contains
+ * the device code.
+ */
+static int pc236_attach(comedi_device * dev, comedi_devconfig * it);
+static int pc236_detach(comedi_device * dev);
+static comedi_driver driver_amplc_pc236 = {
+      driver_name:PC236_DRIVER_NAME,
+      module:THIS_MODULE,
+      attach:pc236_attach,
+      detach:pc236_detach,
+      board_name:&pc236_boards[0].name,
+      offset:sizeof(pc236_board),
+      num_names:sizeof(pc236_boards) / sizeof(pc236_board),
+};
+
+#ifdef CONFIG_COMEDI_PCI
+COMEDI_PCI_INITCLEANUP(driver_amplc_pc236, pc236_pci_table);
+#else
+COMEDI_INITCLEANUP(driver_amplc_pc236);
+#endif
+
+static int pc236_request_region(unsigned minor, unsigned long from,
+	unsigned long extent);
+static void pc236_intr_disable(comedi_device * dev);
+static void pc236_intr_enable(comedi_device * dev);
+static int pc236_intr_check(comedi_device * dev);
+static int pc236_intr_insn(comedi_device * dev, comedi_subdevice * s,
+	comedi_insn * insn, lsampl_t * data);
+static int pc236_intr_cmdtest(comedi_device * dev, comedi_subdevice * s,
+	comedi_cmd * cmd);
+static int pc236_intr_cmd(comedi_device * dev, comedi_subdevice * s);
+static int pc236_intr_cancel(comedi_device * dev, comedi_subdevice * s);
+static irqreturn_t pc236_interrupt(int irq, void *d PT_REGS_ARG);
+
+/*
+ * This function looks for a PCI device matching the requested board name,
+ * bus and slot.
+ */
+#ifdef CONFIG_COMEDI_PCI
+static int
+pc236_find_pci(comedi_device * dev, int bus, int slot,
+	struct pci_dev **pci_dev_p)
+{
+	struct pci_dev *pci_dev = NULL;
+
+	*pci_dev_p = NULL;
+
+	/* Look for matching PCI device. */
+	for (pci_dev = pci_get_device(PCI_VENDOR_ID_AMPLICON, PCI_ANY_ID, NULL);
+		pci_dev != NULL;
+		pci_dev = pci_get_device(PCI_VENDOR_ID_AMPLICON,
+			PCI_ANY_ID, pci_dev)) {
+		/* If bus/slot specified, check them. */
+		if (bus || slot) {
+			if (bus != pci_dev->bus->number
+				|| slot != PCI_SLOT(pci_dev->devfn))
+				continue;
+		}
+		if (thisboard->model == anypci_model) {
+			/* Match any supported model. */
+			int i;
+
+			for (i = 0; i < ARRAY_SIZE(pc236_boards); i++) {
+				if (pc236_boards[i].bustype != pci_bustype)
+					continue;
+				if (pci_dev->device == pc236_boards[i].devid) {
+					/* Change board_ptr to matched board. */
+					dev->board_ptr = &pc236_boards[i];
+					break;
+				}
+			}
+			if (i == ARRAY_SIZE(pc236_boards))
+				continue;
+		} else {
+			/* Match specific model name. */
+			if (pci_dev->device != thisboard->devid)
+				continue;
+		}
+
+		/* Found a match. */
+		*pci_dev_p = pci_dev;
+		return 0;
+	}
+	/* No match found. */
+	if (bus || slot) {
+		printk(KERN_ERR
+			"comedi%d: error! no %s found at pci %02x:%02x!\n",
+			dev->minor, thisboard->name, bus, slot);
+	} else {
+		printk(KERN_ERR "comedi%d: error! no %s found!\n",
+			dev->minor, thisboard->name);
+	}
+	return -EIO;
+}
+#endif
+
+/*
+ * Attach is called by the Comedi core to configure the driver
+ * for a particular board.  If you specified a board_name array
+ * in the driver structure, dev->board_ptr contains that
+ * address.
+ */
+static int pc236_attach(comedi_device * dev, comedi_devconfig * it)
+{
+	comedi_subdevice *s;
+	unsigned long iobase = 0;
+	unsigned int irq = 0;
+#ifdef CONFIG_COMEDI_PCI
+	struct pci_dev *pci_dev = NULL;
+	int bus = 0, slot = 0;
+#endif
+	int share_irq = 0;
+	int ret;
+
+	printk(KERN_DEBUG "comedi%d: %s: attach\n", dev->minor,
+		PC236_DRIVER_NAME);
+/*
+ * Allocate the private structure area.  alloc_private() is a
+ * convenient macro defined in comedidev.h.
+ */
+	if ((ret = alloc_private(dev, sizeof(pc236_private))) < 0) {
+		printk(KERN_ERR "comedi%d: error! out of memory!\n",
+			dev->minor);
+		return ret;
+	}
+	/* Process options. */
+	switch (thisboard->bustype) {
+	case isa_bustype:
+		iobase = it->options[0];
+		irq = it->options[1];
+		share_irq = 0;
+		break;
+#ifdef CONFIG_COMEDI_PCI
+	case pci_bustype:
+		bus = it->options[0];
+		slot = it->options[1];
+		share_irq = 1;
+
+		if ((ret = pc236_find_pci(dev, bus, slot, &pci_dev)) < 0)
+			return ret;
+		devpriv->pci_dev = pci_dev;
+		break;
+#endif /* CONFIG_COMEDI_PCI */
+	default:
+		printk(KERN_ERR
+			"comedi%d: %s: BUG! cannot determine board type!\n",
+			dev->minor, PC236_DRIVER_NAME);
+		return -EINVAL;
+		break;
+	}
+
+/*
+ * Initialize dev->board_name.
+ */
+	dev->board_name = thisboard->name;
+
+	/* Enable device and reserve I/O spaces. */
+#ifdef CONFIG_COMEDI_PCI
+	if (pci_dev) {
+		if ((ret = comedi_pci_enable(pci_dev, PC236_DRIVER_NAME)) < 0) {
+			printk(KERN_ERR
+				"comedi%d: error! cannot enable PCI device and request regions!\n",
+				dev->minor);
+			return ret;
+		}
+		devpriv->lcr_iobase = pci_resource_start(pci_dev, 1);
+		iobase = pci_resource_start(pci_dev, 2);
+		irq = pci_dev->irq;
+	} else
+#endif
+	{
+		ret = pc236_request_region(dev->minor, iobase, PC236_IO_SIZE);
+		if (ret < 0) {
+			return ret;
+		}
+	}
+	dev->iobase = iobase;
+
+/*
+ * Allocate the subdevice structures.  alloc_subdevice() is a
+ * convenient macro defined in comedidev.h.
+ */
+	if ((ret = alloc_subdevices(dev, 2)) < 0) {
+		printk(KERN_ERR "comedi%d: error! out of memory!\n",
+			dev->minor);
+		return ret;
+	}
+
+	s = dev->subdevices + 0;
+	/* digital i/o subdevice (8255) */
+	if ((ret = subdev_8255_init(dev, s, NULL, iobase)) < 0) {
+		printk(KERN_ERR "comedi%d: error! out of memory!\n",
+			dev->minor);
+		return ret;
+	}
+	s = dev->subdevices + 1;
+	dev->read_subdev = s;
+	s->type = COMEDI_SUBD_UNUSED;
+	pc236_intr_disable(dev);
+	if (irq) {
+		unsigned long flags = share_irq ? IRQF_SHARED : 0;
+
+		if (comedi_request_irq(irq, pc236_interrupt, flags,
+				PC236_DRIVER_NAME, dev) >= 0) {
+			dev->irq = irq;
+			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 = pc236_intr_insn;
+			s->do_cmdtest = pc236_intr_cmdtest;
+			s->do_cmd = pc236_intr_cmd;
+			s->cancel = pc236_intr_cancel;
+		}
+	}
+	printk(KERN_INFO "comedi%d: %s ", dev->minor, dev->board_name);
+	if (thisboard->bustype == isa_bustype) {
+		printk("(base %#lx) ", iobase);
+	} else {
+#ifdef CONFIG_COMEDI_PCI
+		printk("(pci %s) ", pci_name(pci_dev));
+#endif
+	}
+	if (irq) {
+		printk("(irq %u%s) ", irq, (dev->irq ? "" : " UNAVAILABLE"));
+	} else {
+		printk("(no irq) ");
+	}
+
+	printk("attached\n");
+
+	return 1;
+}
+
+/*
+ * _detach is called to deconfigure a device.  It should deallocate
+ * resources.
+ * This function is also called when _attach() fails, so it should be
+ * careful not to release resources that were not necessarily
+ * allocated by _attach().  dev->private and dev->subdevices are
+ * deallocated automatically by the core.
+ */
+static int pc236_detach(comedi_device * dev)
+{
+	printk(KERN_DEBUG "comedi%d: %s: detach\n", dev->minor,
+		PC236_DRIVER_NAME);
+	if (devpriv) {
+		pc236_intr_disable(dev);
+	}
+	if (dev->irq)
+		comedi_free_irq(dev->irq, dev);
+	if (dev->subdevices) {
+		subdev_8255_cleanup(dev, dev->subdevices + 0);
+	}
+	if (devpriv) {
+#ifdef CONFIG_COMEDI_PCI
+		if (devpriv->pci_dev) {
+			if (dev->iobase) {
+				comedi_pci_disable(devpriv->pci_dev);
+			}
+			pci_dev_put(devpriv->pci_dev);
+		} else
+#endif
+		{
+			if (dev->iobase) {
+				release_region(dev->iobase, PC236_IO_SIZE);
+			}
+		}
+	}
+	if (dev->board_name) {
+		printk(KERN_INFO "comedi%d: %s removed\n",
+			dev->minor, dev->board_name);
+	}
+	return 0;
+}
+
+/*
+ * This function checks and requests an I/O region, reporting an error
+ * if there is a conflict.
+ */
+static int pc236_request_region(unsigned minor, unsigned long from,
+	unsigned long extent)
+{
+	if (!from || !request_region(from, extent, PC236_DRIVER_NAME)) {
+		printk(KERN_ERR "comedi%d: I/O port conflict (%#lx,%lu)!\n",
+			minor, from, extent);
+		return -EIO;
+	}
+	return 0;
+}
+
+/*
+ * This function is called to mark the interrupt as disabled (no command
+ * configured on subdevice 1) and to physically disable the interrupt
+ * (not possible on the PC36AT, except by removing the IRQ jumper!).
+ */
+static void pc236_intr_disable(comedi_device * dev)
+{
+	unsigned long flags;
+
+	comedi_spin_lock_irqsave(&dev->spinlock, flags);
+	devpriv->enable_irq = 0;
+#ifdef CONFIG_COMEDI_PCI
+	if (devpriv->lcr_iobase)
+		outl(PCI236_INTR_DISABLE, devpriv->lcr_iobase + PLX9052_INTCSR);
+#endif
+	comedi_spin_unlock_irqrestore(&dev->spinlock, flags);
+}
+
+/*
+ * This function is called to mark the interrupt as enabled (a command
+ * configured on subdevice 1) and to physically enable the interrupt
+ * (not possible on the PC36AT, except by (re)connecting the IRQ jumper!).
+ */
+static void pc236_intr_enable(comedi_device * dev)
+{
+	unsigned long flags;
+
+	comedi_spin_lock_irqsave(&dev->spinlock, flags);
+	devpriv->enable_irq = 1;
+#ifdef CONFIG_COMEDI_PCI
+	if (devpriv->lcr_iobase)
+		outl(PCI236_INTR_ENABLE, devpriv->lcr_iobase + PLX9052_INTCSR);
+#endif
+	comedi_spin_unlock_irqrestore(&dev->spinlock, flags);
+}
+
+/*
+ * This function is called when an interrupt occurs to check whether
+ * the interrupt has been marked as enabled and was generated by the
+ * board.  If so, the function prepares the hardware for the next
+ * interrupt.
+ * Returns 0 if the interrupt should be ignored.
+ */
+static int pc236_intr_check(comedi_device * dev)
+{
+	int retval = 0;
+	unsigned long flags;
+
+	comedi_spin_lock_irqsave(&dev->spinlock, flags);
+	if (devpriv->enable_irq) {
+		retval = 1;
+#ifdef CONFIG_COMEDI_PCI
+		if (devpriv->lcr_iobase) {
+			if ((inl(devpriv->lcr_iobase + PLX9052_INTCSR)
+					& PLX9052_INTCSR_LI1STAT_MASK)
+				== PLX9052_INTCSR_LI1STAT_INACTIVE) {
+				retval = 0;
+			} else {
+				/* Clear interrupt and keep it enabled. */
+				outl(PCI236_INTR_ENABLE,
+					devpriv->lcr_iobase + PLX9052_INTCSR);
+			}
+		}
+#endif
+	}
+	comedi_spin_unlock_irqrestore(&dev->spinlock, flags);
+
+	return retval;
+}
+
+/*
+ * Input from subdevice 1.
+ * Copied from the comedi_parport driver.
+ */
+static int pc236_intr_insn(comedi_device * dev, comedi_subdevice * s,
+	comedi_insn * insn, lsampl_t * data)
+{
+	data[1] = 0;
+	return 2;
+}
+
+/*
+ * Subdevice 1 command test.
+ * Copied from the comedi_parport driver.
+ */
+static int pc236_intr_cmdtest(comedi_device * dev, comedi_subdevice * s,
+	comedi_cmd * cmd)
+{
+	int err = 0;
+	int tmp;
+
+	/* step 1 */
+
+	tmp = cmd->start_src;
+	cmd->start_src &= TRIG_NOW;
+	if (!cmd->start_src || tmp != cmd->start_src)
+		err++;
+
+	tmp = cmd->scan_begin_src;
+	cmd->scan_begin_src &= TRIG_EXT;
+	if (!cmd->scan_begin_src || tmp != cmd->scan_begin_src)
+		err++;
+
+	tmp = cmd->convert_src;
+	cmd->convert_src &= TRIG_FOLLOW;
+	if (!cmd->convert_src || tmp != cmd->convert_src)
+		err++;
+
+	tmp = cmd->scan_end_src;
+	cmd->scan_end_src &= TRIG_COUNT;
+	if (!cmd->scan_end_src || tmp != cmd->scan_end_src)
+		err++;
+
+	tmp = cmd->stop_src;
+	cmd->stop_src &= TRIG_NONE;
+	if (!cmd->stop_src || tmp != cmd->stop_src)
+		err++;
+
+	if (err)
+		return 1;
+
+	/* step 2: ignored */
+
+	if (err)
+		return 2;
+
+	/* step 3: */
+
+	if (cmd->start_arg != 0) {
+		cmd->start_arg = 0;
+		err++;
+	}
+	if (cmd->scan_begin_arg != 0) {
+		cmd->scan_begin_arg = 0;
+		err++;
+	}
+	if (cmd->convert_arg != 0) {
+		cmd->convert_arg = 0;
+		err++;
+	}
+	if (cmd->scan_end_arg != 1) {
+		cmd->scan_end_arg = 1;
+		err++;
+	}
+	if (cmd->stop_arg != 0) {
+		cmd->stop_arg = 0;
+		err++;
+	}
+
+	if (err)
+		return 3;
+
+	/* step 4: ignored */
+
+	if (err)
+		return 4;
+
+	return 0;
+}
+
+/*
+ * Subdevice 1 command.
+ */
+static int pc236_intr_cmd(comedi_device * dev, comedi_subdevice * s)
+{
+	pc236_intr_enable(dev);
+
+	return 0;
+}
+
+/*
+ * Subdevice 1 cancel command.
+ */
+static int pc236_intr_cancel(comedi_device * dev, comedi_subdevice * s)
+{
+	pc236_intr_disable(dev);
+
+	return 0;
+}
+
+/*
+ * Interrupt service routine.
+ * Based on the comedi_parport driver.
+ */
+static irqreturn_t pc236_interrupt(int irq, void *d PT_REGS_ARG)
+{
+	comedi_device *dev = d;
+	comedi_subdevice *s = dev->subdevices + 1;
+	int handled;
+
+	handled = pc236_intr_check(dev);
+	if (dev->attached && handled) {
+		comedi_buf_put(s->async, 0);
+		s->async->events |= COMEDI_CB_BLOCK | COMEDI_CB_EOS;
+		comedi_event(dev, s);
+	}
+	return IRQ_RETVAL(handled);
+}