1 files changed, 512 insertions, 0 deletions

diff --git a/drivers/parport/daisy.c b/drivers/parport/daisy.c
new file mode 100644
index 000000000000..075c7eb5c85d
--- /dev/null
+++ b/drivers/parport/daisy.c
@@ -0,0 +1,512 @@
+/*
+ * IEEE 1284.3 Parallel port daisy chain and multiplexor code
+ * 
+ * Copyright (C) 1999, 2000  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.
+ * 22-02-2000: Count devices that are actually detected.
+ *
+ * Any part of this program may be used in documents licensed under
+ * the GNU Free Documentation License, Version 1.1 or any later version
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/parport.h>
+#include <linux/delay.h>
+#include <linux/sched.h>
+
+#include <asm/current.h>
+#include <asm/uaccess.h>
+
+#undef DEBUG
+
+#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 DEFINE_SPINLOCK(topology_lock);
+
+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, **p;
+        newdev = kmalloc (sizeof (struct daisydev), GFP_KERNEL);
+        if (newdev) {
+                newdev->port = port;
+                newdev->daisy = daisy;
+                newdev->devnum = devnum;
+                spin_lock(&topology_lock);
+                for (p = &topology; *p && (*p)->devnum<devnum; p = &(*p)->next)
+                        ;
+                newdev->next = *p;
+                *p = newdev;
+                spin_unlock(&topology_lock);
+        }
+}
+
+/* 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;
+                real->slaves[muxport-1] = extra;
+        }
+
+        return extra;
+}
+
+/* Discover the IEEE1284.3 topology on a port -- muxes and daisy chains.
+ * Return value is number of devices actually detected. */
+int parport_daisy_init (struct parport *port)
+{
+        int detected = 0;
+        char *deviceid;
+        static const char *th[] = { /*0*/"th", "st", "nd", "rd", "th" };
+        int num_ports;
+        int i;
+        int last_try = 0;
+
+again:
+        /* 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_daisy_init(extra);
+                }
+        }
+
+        if (port->muxport >= 0)
+                select_port (port);
+
+        parport_daisy_deselect_all (port);
+        detected += 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) {
+                if (parport_device_id (numdevs - 1, deviceid, 1000) > 2)
+                        detected++;
+
+                kfree (deviceid);
+        }
+
+        if (!detected && !last_try) {
+                /* No devices were detected.  Perhaps they are in some
+                   funny state; let's try to reset them and see if
+                   they wake up. */
+                parport_daisy_fini (port);
+                parport_write_control (port, PARPORT_CONTROL_SELECT);
+                udelay (50);
+                parport_write_control (port,
+                                       PARPORT_CONTROL_SELECT |
+                                       PARPORT_CONTROL_INIT);
+                udelay (50);
+                last_try = 1;
+                goto again;
+        }
+
+        return detected;
+}
+
+/* Forget about devices on a physical port. */
+void parport_daisy_fini (struct parport *port)
+{
+        struct daisydev **p;
+
+        spin_lock(&topology_lock);
+        p = &topology;
+        while (*p) {
+                struct daisydev *dev = *p;
+                if (dev->port != port) {
+                        p = &dev->next;
+                        continue;
+                }
+                *p = dev->next;
+                kfree(dev);
+        }
+
+        /* Gaps in the numbering could be handled better.  How should
+           someone enumerate through all IEEE1284.3 devices in the
+           topology?. */
+        if (!topology) numdevs = 0;
+        spin_unlock(&topology_lock);
+        return;
+}
+
+/**
+ *      parport_open - find a device by canonical device number
+ *      @devnum: canonical device number
+ *      @name: name to associate with the device
+ *      @pf: preemption callback
+ *      @kf: kick callback
+ *      @irqf: interrupt handler
+ *      @flags: registration flags
+ *      @handle: driver data
+ *
+ *      This function is similar to parport_register_device(), except
+ *      that it locates a device by its number rather than by the port
+ *      it is attached to.
+ *
+ *      All parameters except for @devnum are the same as for
+ *      parport_register_device().  The return value is the same as
+ *      for parport_register_device().
+ **/
+
+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 daisydev *p = topology;
+        struct parport *port;
+        struct pardevice *dev;
+        int daisy;
+
+        spin_lock(&topology_lock);
+        while (p && p->devnum != devnum)
+                p = p->next;
+
+        if (!p) {
+                spin_unlock(&topology_lock);
+                return NULL;
+        }
+
+        daisy = p->daisy;
+        port = parport_get_port(p->port);
+        spin_unlock(&topology_lock);
+
+        dev = parport_register_device (port, name, pf, kf,
+                                       irqf, flags, handle);
+        parport_put_port(port);
+        if (!dev)
+                return NULL;
+
+        dev->daisy = daisy;
+
+        /* Check that there really is a device to select. */
+        if (daisy >= 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;
+}
+
+/**
+ *      parport_close - close a device opened with parport_open()
+ *      @dev: device to close
+ *
+ *      This is to parport_open() as parport_unregister_device() is to
+ *      parport_register_device().
+ **/
+
+void parport_close (struct pardevice *dev)
+{
+        parport_unregister_device (dev);
+}
+
+/**
+ *      parport_device_num - convert device coordinates
+ *      @parport: parallel port number
+ *      @mux: multiplexor port number (-1 for no multiplexor)
+ *      @daisy: daisy chain address (-1 for no daisy chain address)
+ *
+ *      This tries to locate a device on the given parallel port,
+ *      multiplexor port and daisy chain address, and returns its
+ *      device number or -NXIO if no device with those coordinates
+ *      exists.
+ **/
+
+int parport_device_num (int parport, int mux, int daisy)
+{
+        int res = -ENXIO;
+        struct daisydev *dev;
+
+        spin_lock(&topology_lock);
+        dev = topology;
+        while (dev && dev->port->portnum != parport &&
+               dev->port->muxport != mux && dev->daisy != daisy)
+                dev = dev->next;
+        if (dev)
+                res = dev->devnum;
+        spin_unlock(&topology_lock);
+
+        return res;
+}
+
+/* Send a daisy-chain-style CPP command packet. */
+static int cpp_daisy (struct parport *port, int cmd)
+{
+        unsigned char s;
+
+        parport_data_forward (port);
+        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_data_forward (port);
+        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)
+{
+        switch (mode)
+        {
+                // For these modes we should switch to EPP mode:
+                case IEEE1284_MODE_EPP:
+                case IEEE1284_MODE_EPPSL:
+                case IEEE1284_MODE_EPPSWE:
+                        return (cpp_daisy (port, 0x20 + daisy) &
+                                PARPORT_STATUS_ERROR);
+
+                // For these modes we should switch to ECP mode:
+                case IEEE1284_MODE_ECP:
+                case IEEE1284_MODE_ECPRLE:
+                case IEEE1284_MODE_ECPSWE: 
+                        return (cpp_daisy (port, 0xd0 + daisy) &
+                                PARPORT_STATUS_ERROR);
+
+                // Nothing was told for BECP in Daisy chain specification.
+                // May be it's wise to use ECP?
+                case IEEE1284_MODE_BECP:
+                // Others use compat mode
+                case IEEE1284_MODE_NIBBLE:
+                case IEEE1284_MODE_BYTE:
+                case IEEE1284_MODE_COMPAT:
+                default:
+                        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;
+        int detected;
+        char *deviceid;
+
+        parport_data_forward (port);
+        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 0;
+        }
+
+        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 0;
+        }
+
+        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);
+        detected = numdevs - thisdev;
+        DPRINTK (KERN_DEBUG "%s: Found %d daisy-chained devices\n", port->name,
+                 detected);
+
+        /* 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 detected;
+}