patch-2.3.10 linux/drivers/misc/parport_daisy.c

• Lines: 474
• Date: Sat Jul 3 10:45:04 1999
• Orig file: v2.3.9/linux/drivers/misc/parport_daisy.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.3.9/linux/drivers/misc/parport_daisy.c linux/drivers/misc/parport_daisy.c
@@ -0,0 +1,473 @@
+/*
+ * IEEE 1284.3 Parallel port daisy chain and multiplexor code
+ * 
+ * Copyright (C) 1999  Tim Waugh <tim@cyberelk.demon.co.uk>
+ *
+ * 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.
+ *
+ * ??-12-1998: Initial implementation.
+ * 31-01-1999: Make port-cloning transparent.
+ * 13-02-1999: Move DeviceID technique from parport_probe.
+ * 13-03-1999: Get DeviceID from non-IEEE 1284.3 devices too.
+ *
+ */
+
+#include <linux/parport.h>
+#include <linux/delay.h>
+#include <asm/uaccess.h>
+
+#define DEBUG /* undef me for production */
+
+#ifdef DEBUG
+#define DPRINTK(stuff...) printk (stuff)
+#else
+#define DPRINTK(stuff...)
+#endif
+
+static struct daisydev {
+	struct daisydev *next;
+	struct parport *port;
+	int daisy;
+	int devnum;
+} *topology = NULL;
+
+static int numdevs = 0;
+
+/* Forward-declaration of lower-level functions. */
+static int mux_present (struct parport *port);
+static int num_mux_ports (struct parport *port);
+static int select_port (struct parport *port);
+static int assign_addrs (struct parport *port);
+
+/* Add a device to the discovered topology. */
+static void add_dev (int devnum, struct parport *port, int daisy)
+{
+	struct daisydev *newdev;
+	newdev = kmalloc (GFP_KERNEL, sizeof (struct daisydev));
+	if (newdev) {
+		newdev->port = port;
+		newdev->daisy = daisy;
+		newdev->devnum = devnum;
+		newdev->next = topology;
+		if (!topology || topology->devnum >= devnum)
+			topology = newdev;
+		else {
+			struct daisydev *prev = topology;
+			while (prev->next && prev->next->devnum < devnum)
+				prev = prev->next;
+			newdev->next = prev->next;
+			prev->next = newdev;
+		}
+	}
+}
+
+/* Clone a parport (actually, make an alias). */
+static struct parport *clone_parport (struct parport *real, int muxport)
+{
+	struct parport *extra = parport_register_port (real->base,
+						       real->irq,
+						       real->dma,
+						       real->ops);
+	if (extra) {
+		extra->portnum = real->portnum;
+		extra->physport = real;
+		extra->muxport = muxport;
+	}
+
+	return extra;
+}
+
+/* Discover the IEEE1284.3 topology on a port -- muxes and daisy chains. */
+int parport_daisy_init (struct parport *port)
+{
+	char *deviceid;
+	static const char *th[] = { /*0*/"th", "st", "nd", "rd", "th" };
+	int num_ports;
+	int i;
+
+	/* Because this is called before any other devices exist,
+	 * we don't have to claim exclusive access.  */
+
+	/* If mux present on normal port, need to create new
+	 * parports for each extra port. */
+	if (port->muxport < 0 && mux_present (port) &&
+	    /* don't be fooled: a mux must have 2 or 4 ports. */
+	    ((num_ports = num_mux_ports (port)) == 2 || num_ports == 4)) {
+		/* Leave original as port zero. */
+		port->muxport = 0;
+		printk (KERN_INFO
+			"%s: 1st (default) port of %d-way multiplexor\n",
+			port->name, num_ports);
+		for (i = 1; i < num_ports; i++) {
+			/* Clone the port. */
+			struct parport *extra = clone_parport (port, i);
+			if (!extra) {
+				if (signal_pending (current))
+					break;
+
+				schedule ();
+				continue;
+			}
+
+			printk (KERN_INFO
+				"%s: %d%s port of %d-way multiplexor on %s\n",
+				extra->name, i + 1, th[i + 1], num_ports,
+				port->name);
+
+			/* Analyse that port too.  We won't recurse
+			   forever because of the 'port->muxport < 0'
+			   test above. */
+			parport_announce_port (extra);
+		}
+	}
+
+	if (port->muxport >= 0)
+		select_port (port);
+
+	parport_daisy_deselect_all (port);
+	assign_addrs (port);
+
+	/* Count the potential legacy device at the end. */
+	add_dev (numdevs++, port, -1);
+
+	/* Find out the legacy device's IEEE 1284 device ID. */
+	deviceid = kmalloc (1000, GFP_KERNEL);
+	if (deviceid) {
+		parport_device_id (numdevs - 1, deviceid, 1000);
+		kfree (deviceid);
+	}
+
+	return 0;
+}
+
+/* Forget about devices on a physical port. */
+void parport_daisy_fini (struct parport *port)
+{
+	struct daisydev *dev, *prev = topology;
+	while (prev && prev->port == port)
+		prev = topology = topology->next;
+
+	while (prev) {
+		dev = prev->next;
+		if (dev && dev->port == port)
+			prev->next = dev->next;
+
+		prev = prev->next;
+	}
+
+	/* Gaps in the numbering could be handled better.  How should
+           someone enumerate through all IEEE1284.3 devices in the
+           topology?. */
+	if (!topology) numdevs = 0;
+	return; }
+
+/* Find a device by canonical device number. */
+struct pardevice *parport_open (int devnum, const char *name,
+				int (*pf) (void *), void (*kf) (void *),
+				void (*irqf) (int, void *, struct pt_regs *),
+				int flags, void *handle)
+{
+	struct parport *port = parport_enumerate ();
+	struct pardevice *dev;
+	int portnum;
+	int muxnum;
+	int daisynum;
+
+	if (parport_device_coords (devnum,  &portnum, &muxnum, &daisynum))
+		return NULL;
+
+	while (port && ((port->portnum != portnum) ||
+			(port->muxport != muxnum)))
+		port = port->next;
+
+	if (!port)
+		/* No corresponding parport. */
+		return NULL;
+
+	dev = parport_register_device (port, name, pf, kf,
+				       irqf, flags, handle);
+	if (dev)
+		dev->daisy = daisynum;
+
+	/* Check that there really is a device to select. */
+	if (daisynum >= 0) {
+		int selected;
+		parport_claim_or_block (dev);
+		selected = port->daisy;
+		parport_release (dev);
+
+		if (selected != port->daisy) {
+			/* No corresponding device. */
+			parport_unregister_device (dev);
+			return NULL;
+		}
+	}
+
+	return dev;
+}
+
+/* The converse of parport_open. */
+void parport_close (struct pardevice *dev)
+{
+	parport_unregister_device (dev);
+}
+
+/* Convert device coordinates into a canonical device number. */
+int parport_device_num (int parport, int mux, int daisy)
+{
+	struct daisydev *dev = topology;
+
+	while (dev && dev->port->portnum != parport &&
+	       dev->port->muxport != mux && dev->daisy != daisy)
+		dev = dev->next;
+
+	if (!dev)
+		return -ENXIO;
+
+	return dev->devnum;
+}
+
+/* Convert a canonical device number into device coordinates. */
+int parport_device_coords (int devnum, int *parport, int *mux, int *daisy)
+{
+	struct daisydev *dev = topology;
+
+	while (dev && dev->devnum != devnum)
+		dev = dev->next;
+
+	if (!dev)
+		return -ENXIO;
+
+	if (parport) *parport = dev->port->portnum;
+	if (mux) *mux = dev->port->muxport;
+	if (daisy) *daisy = dev->daisy;
+	return 0;
+}
+
+/* Send a daisy-chain-style CPP command packet. */
+static int cpp_daisy (struct parport *port, int cmd)
+{
+	unsigned char s;
+
+	parport_write_data (port, 0xaa); udelay (2);
+	parport_write_data (port, 0x55); udelay (2);
+	parport_write_data (port, 0x00); udelay (2);
+	parport_write_data (port, 0xff); udelay (2);
+	s = parport_read_status (port) & (PARPORT_STATUS_BUSY
+					  | PARPORT_STATUS_PAPEROUT
+					  | PARPORT_STATUS_SELECT
+					  | PARPORT_STATUS_ERROR);
+	if (s != (PARPORT_STATUS_BUSY
+		  | PARPORT_STATUS_PAPEROUT
+		  | PARPORT_STATUS_SELECT
+		  | PARPORT_STATUS_ERROR)) {
+		DPRINTK (KERN_DEBUG "%s: cpp_daisy: aa5500ff(%02x)\n",
+			 port->name, s);
+		return -ENXIO;
+	}
+
+	parport_write_data (port, 0x87); udelay (2);
+	s = parport_read_status (port) & (PARPORT_STATUS_BUSY
+					  | PARPORT_STATUS_PAPEROUT
+					  | PARPORT_STATUS_SELECT
+					  | PARPORT_STATUS_ERROR);
+	if (s != (PARPORT_STATUS_SELECT | PARPORT_STATUS_ERROR)) {
+		DPRINTK (KERN_DEBUG "%s: cpp_daisy: aa5500ff87(%02x)\n",
+			 port->name, s);
+		return -ENXIO;
+	}
+
+	parport_write_data (port, 0x78); udelay (2);
+	parport_write_data (port, cmd); udelay (2);
+	parport_frob_control (port,
+			      PARPORT_CONTROL_STROBE,
+			      PARPORT_CONTROL_STROBE);
+	udelay (1);
+	parport_frob_control (port, PARPORT_CONTROL_STROBE, 0);
+	udelay (1);
+	s = parport_read_status (port);
+	parport_write_data (port, 0xff); udelay (2);
+
+	return s;
+}
+
+/* Send a mux-style CPP command packet. */
+static int cpp_mux (struct parport *port, int cmd)
+{
+	unsigned char s;
+	int rc;
+
+	parport_write_data (port, 0xaa); udelay (2);
+	parport_write_data (port, 0x55); udelay (2);
+	parport_write_data (port, 0xf0); udelay (2);
+	parport_write_data (port, 0x0f); udelay (2);
+	parport_write_data (port, 0x52); udelay (2);
+	parport_write_data (port, 0xad); udelay (2);
+	parport_write_data (port, cmd); udelay (2);
+
+	s = parport_read_status (port);
+	if (!(s & PARPORT_STATUS_ACK)) {
+		DPRINTK (KERN_DEBUG "%s: cpp_mux: aa55f00f52ad%02x(%02x)\n",
+			 port->name, cmd, s);
+		return -EIO;
+	}
+
+	rc = (((s & PARPORT_STATUS_SELECT   ? 1 : 0) << 0) |
+	      ((s & PARPORT_STATUS_PAPEROUT ? 1 : 0) << 1) |
+	      ((s & PARPORT_STATUS_BUSY     ? 0 : 1) << 2) |
+	      ((s & PARPORT_STATUS_ERROR    ? 0 : 1) << 3));
+
+	return rc;
+}
+
+void parport_daisy_deselect_all (struct parport *port)
+{
+	cpp_daisy (port, 0x30);
+}
+
+int parport_daisy_select (struct parport *port, int daisy, int mode)
+{
+	/* mode is currently ignored. FIXME? */
+	return cpp_daisy (port, 0xe0 + daisy) & PARPORT_STATUS_ERROR;
+}
+
+static int mux_present (struct parport *port)
+{
+	return cpp_mux (port, 0x51) == 3;
+}
+
+static int num_mux_ports (struct parport *port)
+{
+	return cpp_mux (port, 0x58);
+}
+
+static int select_port (struct parport *port)
+{
+	int muxport = port->muxport;
+	return cpp_mux (port, 0x60 + muxport) == muxport;
+}
+
+static int assign_addrs (struct parport *port)
+{
+	unsigned char s, last_dev;
+	unsigned char daisy;
+	int thisdev = numdevs;
+	char *deviceid;
+
+	parport_write_data (port, 0xaa); udelay (2);
+	parport_write_data (port, 0x55); udelay (2);
+	parport_write_data (port, 0x00); udelay (2);
+	parport_write_data (port, 0xff); udelay (2);
+	s = parport_read_status (port) & (PARPORT_STATUS_BUSY
+					  | PARPORT_STATUS_PAPEROUT
+					  | PARPORT_STATUS_SELECT
+					  | PARPORT_STATUS_ERROR);
+	if (s != (PARPORT_STATUS_BUSY
+		  | PARPORT_STATUS_PAPEROUT
+		  | PARPORT_STATUS_SELECT
+		  | PARPORT_STATUS_ERROR)) {
+		DPRINTK (KERN_DEBUG "%s: assign_addrs: aa5500ff(%02x)\n",
+			 port->name, s);
+		return -ENXIO;
+	}
+
+	parport_write_data (port, 0x87); udelay (2);
+	s = parport_read_status (port) & (PARPORT_STATUS_BUSY
+					  | PARPORT_STATUS_PAPEROUT
+					  | PARPORT_STATUS_SELECT
+					  | PARPORT_STATUS_ERROR);
+	if (s != (PARPORT_STATUS_SELECT | PARPORT_STATUS_ERROR)) {
+		DPRINTK (KERN_DEBUG "%s: assign_addrs: aa5500ff87(%02x)\n",
+			 port->name, s);
+		return -ENXIO;
+	}
+
+	parport_write_data (port, 0x78); udelay (2);
+	last_dev = 0; /* We've just been speaking to a device, so we
+			 know there must be at least _one_ out there. */
+
+	for (daisy = 0; daisy < 4; daisy++) {
+		parport_write_data (port, daisy);
+		udelay (2);
+		parport_frob_control (port,
+				      PARPORT_CONTROL_STROBE,
+				      PARPORT_CONTROL_STROBE);
+		udelay (1);
+		parport_frob_control (port, PARPORT_CONTROL_STROBE, 0);
+		udelay (1);
+
+		if (last_dev)
+			/* No more devices. */
+			break;
+
+		last_dev = !(parport_read_status (port)
+			     & PARPORT_STATUS_BUSY);
+
+		add_dev (numdevs++, port, daisy);
+	}
+
+	parport_write_data (port, 0xff); udelay (2);
+	DPRINTK (KERN_DEBUG "%s: Found %d daisy-chained devices\n", port->name,
+		numdevs - thisdev);
+
+	/* Ask the new devices to introduce themselves. */
+	deviceid = kmalloc (1000, GFP_KERNEL);
+	if (!deviceid) return 0;
+
+	for (daisy = 0; thisdev < numdevs; thisdev++, daisy++)
+		parport_device_id (thisdev, deviceid, 1000);
+
+	kfree (deviceid);
+	return 0;
+}
+
+/* Find a device with a particular manufacturer and model string,
+   starting from a given device number.  Like the PCI equivalent,
+   'from' itself is skipped. */
+int parport_find_device (const char *mfg, const char *mdl, int from)
+{
+	struct daisydev *d = topology; /* sorted by devnum */
+
+	/* Find where to start. */
+	while (d && d->devnum <= from)
+		d = d->next;
+
+	/* Search. */
+	while (d) {
+		struct parport_device_info *info;
+		info = &d->port->probe_info[1 + d->daisy];
+		if ((!mfg || !strcmp (mfg, info->mfr)) &&
+		    (!mdl || !strcmp (mdl, info->model)))
+			break;
+
+		d = d->next;
+	}
+
+	if (d)
+		return d->devnum;
+
+	return -1;
+}
+
+/* Find a device in a particular class.  Like the PCI equivalent,
+   'from' itself is skipped. */
+int parport_find_class (parport_device_class cls, int from)
+{
+	struct daisydev *d = topology; /* sorted by devnum */
+
+	/* Find where to start. */
+	while (d && d->devnum <= from)
+		d = d->next;
+
+	/* Search. */
+	while (d && d->port->probe_info[1 + d->daisy].class != cls)
+		d = d->next;
+
+	if (d)
+		return d->devnum;
+
+	return -1;
+}