1 files changed, 661 insertions, 0 deletions

diff --git a/drivers/macintosh/via-maciisi.c b/drivers/macintosh/via-maciisi.c
new file mode 100644
index 000000000000..a1966975d58f
--- /dev/null
+++ b/drivers/macintosh/via-maciisi.c
@@ -0,0 +1,661 @@
+/*
+ * Device driver for the IIsi-style ADB on some Mac LC and II-class machines
+ *
+ * Based on via-cuda.c and via-macii.c, as well as the original
+ * adb-bus.c, which in turn is somewhat influenced by (but uses no
+ * code from) the NetBSD HWDIRECT ADB code.  Original IIsi driver work
+ * was done by Robert Thompson and integrated into the old style
+ * driver by Michael Schmitz.
+ *
+ * Original sources (c) Alan Cox, Paul Mackerras, and others.
+ *
+ * Rewritten for Unified ADB by David Huggins-Daines <dhd@debian.org>
+ * 
+ * 7/13/2000- extensive changes by Andrew McPherson <andrew@macduff.dhs.org>
+ * Works about 30% of the time now.
+ */
+
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/adb.h>
+#include <linux/cuda.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <asm/macintosh.h>
+#include <asm/macints.h>
+#include <asm/machw.h>
+#include <asm/mac_via.h>
+
+static volatile unsigned char *via;
+
+/* VIA registers - spaced 0x200 bytes apart - only the ones we actually use */
+#define RS              0x200           /* skip between registers */
+#define B               0               /* B-side data */
+#define A               RS              /* A-side data */
+#define DIRB            (2*RS)          /* B-side direction (1=output) */
+#define DIRA            (3*RS)          /* A-side direction (1=output) */
+#define SR              (10*RS)         /* Shift register */
+#define ACR             (11*RS)         /* Auxiliary control register */
+#define IFR             (13*RS)         /* Interrupt flag register */
+#define IER             (14*RS)         /* Interrupt enable register */
+
+/* Bits in B data register: all active low */
+#define TREQ            0x08            /* Transfer request (input) */
+#define TACK            0x10            /* Transfer acknowledge (output) */
+#define TIP             0x20            /* Transfer in progress (output) */
+#define ST_MASK         0x30            /* mask for selecting ADB state bits */
+
+/* Bits in ACR */
+#define SR_CTRL         0x1c            /* Shift register control bits */
+#define SR_EXT          0x0c            /* Shift on external clock */
+#define SR_OUT          0x10            /* Shift out if 1 */
+
+/* Bits in IFR and IER */
+#define IER_SET         0x80            /* set bits in IER */
+#define IER_CLR         0               /* clear bits in IER */
+#define SR_INT          0x04            /* Shift register full/empty */
+#define SR_DATA         0x08            /* Shift register data */
+#define SR_CLOCK        0x10            /* Shift register clock */
+
+#define ADB_DELAY 150
+
+#undef DEBUG_MACIISI_ADB
+
+static struct adb_request* current_req = NULL;
+static struct adb_request* last_req = NULL;
+static unsigned char maciisi_rbuf[16];
+static unsigned char *reply_ptr = NULL;
+static int data_index;
+static int reading_reply;
+static int reply_len;
+static int tmp;
+static int need_sync;
+
+static enum maciisi_state {
+    idle,
+    sending,
+    reading,
+} maciisi_state;
+
+static int maciisi_probe(void);
+static int maciisi_init(void);
+static int maciisi_send_request(struct adb_request* req, int sync);
+static void maciisi_sync(struct adb_request *req);
+static int maciisi_write(struct adb_request* req);
+static irqreturn_t maciisi_interrupt(int irq, void* arg, struct pt_regs* regs);
+static void maciisi_input(unsigned char *buf, int nb, struct pt_regs *regs);
+static int maciisi_init_via(void);
+static void maciisi_poll(void);
+static int maciisi_start(void);
+
+struct adb_driver via_maciisi_driver = {
+        "Mac IIsi",
+        maciisi_probe,
+        maciisi_init,
+        maciisi_send_request,
+        NULL, /* maciisi_adb_autopoll, */
+        maciisi_poll,
+        NULL /* maciisi_reset_adb_bus */
+};
+
+static int
+maciisi_probe(void)
+{
+        if (macintosh_config->adb_type != MAC_ADB_IISI)
+                return -ENODEV;
+
+        via = via1;
+        return 0;
+}
+
+static int
+maciisi_init(void)
+{
+        int err;
+
+        if (via == NULL)
+                return -ENODEV;
+
+        if ((err = maciisi_init_via())) {
+                printk(KERN_ERR "maciisi_init: maciisi_init_via() failed, code %d\n", err);
+                via = NULL;
+                return err;
+        }
+
+        if (request_irq(IRQ_MAC_ADB, maciisi_interrupt, IRQ_FLG_LOCK | IRQ_FLG_FAST, 
+                        "ADB", maciisi_interrupt)) {
+                printk(KERN_ERR "maciisi_init: can't get irq %d\n", IRQ_MAC_ADB);
+                return -EAGAIN;
+        }
+
+        printk("adb: Mac IIsi driver v0.2 for Unified ADB.\n");
+        return 0;
+}
+
+/* Flush data from the ADB controller */
+static void
+maciisi_stfu(void)
+{
+        int status = via[B] & (TIP|TREQ);
+
+        if (status & TREQ) {
+#ifdef DEBUG_MACIISI_ADB
+                printk (KERN_DEBUG "maciisi_stfu called with TREQ high!\n");
+#endif
+                return;
+        }
+        
+        udelay(ADB_DELAY);
+        via[ACR] &= ~SR_OUT;
+        via[IER] = IER_CLR | SR_INT;
+
+        udelay(ADB_DELAY);
+
+        status = via[B] & (TIP|TREQ);
+
+        if (!(status & TREQ))
+        {
+                via[B] |= TIP;
+
+                while(1)
+                {
+                        int poll_timeout = ADB_DELAY * 5;
+                        /* Poll for SR interrupt */
+                        while (!(via[IFR] & SR_INT) && poll_timeout-- > 0)
+                                status = via[B] & (TIP|TREQ);
+
+                        tmp = via[SR]; /* Clear shift register */
+#ifdef DEBUG_MACIISI_ADB
+                        printk(KERN_DEBUG "maciisi_stfu: status %x timeout %d data %x\n",
+                               status, poll_timeout, tmp);
+#endif  
+                        if(via[B] & TREQ)
+                                break;
+        
+                        /* ACK on-off */
+                        via[B] |= TACK;
+                        udelay(ADB_DELAY);
+                        via[B] &= ~TACK;
+                }
+
+                /* end frame */
+                via[B] &= ~TIP;
+                udelay(ADB_DELAY);
+        }
+
+        via[IER] = IER_SET | SR_INT;    
+}
+
+/* All specifically VIA-related initialization goes here */
+static int
+maciisi_init_via(void)
+{
+        int     i;
+        
+        /* Set the lines up. We want TREQ as input TACK|TIP as output */
+        via[DIRB] = (via[DIRB] | TACK | TIP) & ~TREQ;
+        /* Shift register on input */
+        via[ACR]  = (via[ACR] & ~SR_CTRL) | SR_EXT;
+#ifdef DEBUG_MACIISI_ADB
+        printk(KERN_DEBUG "maciisi_init_via: initial status %x\n", via[B] & (TIP|TREQ));
+#endif
+        /* Wipe any pending data and int */
+        tmp = via[SR];
+        /* Enable keyboard interrupts */
+        via[IER] = IER_SET | SR_INT;
+        /* Set initial state: idle */
+        via[B] &= ~(TACK|TIP);
+        /* Clear interrupt bit */
+        via[IFR] = SR_INT;
+
+        for(i = 0; i < 60; i++) {
+                udelay(ADB_DELAY);
+                maciisi_stfu();
+                udelay(ADB_DELAY);
+                if(via[B] & TREQ)
+                        break;
+        }
+        if (i == 60)
+                printk(KERN_ERR "maciisi_init_via: bus jam?\n");
+
+        maciisi_state = idle;
+        need_sync = 0;
+
+        return 0;
+}
+
+/* Send a request, possibly waiting for a reply */
+static int
+maciisi_send_request(struct adb_request* req, int sync)
+{
+        int i;
+
+#ifdef DEBUG_MACIISI_ADB
+        static int dump_packet = 0;
+#endif
+
+        if (via == NULL) {
+                req->complete = 1;
+                return -ENXIO;
+        }
+
+#ifdef DEBUG_MACIISI_ADB
+        if (dump_packet) {
+                printk(KERN_DEBUG "maciisi_send_request:");
+                for (i = 0; i < req->nbytes; i++) {
+                        printk(" %.2x", req->data[i]);
+                }
+                printk(" sync %d\n", sync);
+        }
+#endif
+
+        req->reply_expected = 1;
+        
+        i = maciisi_write(req);
+        if (i)
+        {
+                /* Normally, if a packet requires syncing, that happens at the end of
+                 * maciisi_send_request. But if the transfer fails, it will be restarted
+                 * by maciisi_interrupt(). We use need_sync to tell maciisi_interrupt
+                 * when to sync a packet that it sends out.
+                 * 
+                 * Suggestions on a better way to do this are welcome.
+                 */
+                if(i == -EBUSY && sync)
+                        need_sync = 1;
+                else
+                        need_sync = 0;
+                return i;
+        }
+        if(sync)
+                maciisi_sync(req);
+        
+        return 0;
+}
+
+/* Poll the ADB chip until the request completes */
+static void maciisi_sync(struct adb_request *req)
+{
+        int count = 0; 
+
+#ifdef DEBUG_MACIISI_ADB
+        printk(KERN_DEBUG "maciisi_sync called\n");
+#endif
+
+        /* If for some reason the ADB chip shuts up on us, we want to avoid an endless loop. */
+        while (!req->complete && count++ < 50) {
+                maciisi_poll();
+        }
+        /* This could be BAD... when the ADB controller doesn't respond
+         * for this long, it's probably not coming back :-( */
+        if(count >= 50) /* Hopefully shouldn't happen */
+                printk(KERN_ERR "maciisi_send_request: poll timed out!\n");
+}
+
+/* Enqueue a request, and run the queue if possible */
+static int
+maciisi_write(struct adb_request* req)
+{
+        unsigned long flags;
+        int i;
+
+        /* We will accept CUDA packets - the VIA sends them to us, so
+           it figures that we should be able to send them to it */
+        if (req->nbytes < 2 || req->data[0] > CUDA_PACKET) {
+                printk(KERN_ERR "maciisi_write: packet too small or not an ADB or CUDA packet\n");
+                req->complete = 1;
+                return -EINVAL;
+        }
+        req->next = 0;
+        req->sent = 0;
+        req->complete = 0;
+        req->reply_len = 0;
+        
+        local_irq_save(flags);
+
+        if (current_req) {
+                last_req->next = req;
+                last_req = req;
+        } else {
+                current_req = req;
+                last_req = req;
+        }
+        if (maciisi_state == idle)
+        {
+                i = maciisi_start();
+                if(i != 0)
+                {
+                        local_irq_restore(flags);
+                        return i;
+                }
+        }
+        else
+        {
+#ifdef DEBUG_MACIISI_ADB
+                printk(KERN_DEBUG "maciisi_write: would start, but state is %d\n", maciisi_state);
+#endif
+                local_irq_restore(flags);
+                return -EBUSY;
+        }
+
+        local_irq_restore(flags);
+
+        return 0;
+}
+
+static int
+maciisi_start(void)
+{
+        struct adb_request* req;
+        int status;
+
+#ifdef DEBUG_MACIISI_ADB
+        status = via[B] & (TIP | TREQ);
+
+        printk(KERN_DEBUG "maciisi_start called, state=%d, status=%x, ifr=%x\n", maciisi_state, status, via[IFR]);
+#endif
+
+        if (maciisi_state != idle) {
+                /* shouldn't happen */
+                printk(KERN_ERR "maciisi_start: maciisi_start called when driver busy!\n");
+                return -EBUSY;
+        }
+
+        req = current_req;
+        if (req == NULL)
+                return -EINVAL;
+
+        status = via[B] & (TIP|TREQ);
+        if (!(status & TREQ)) {
+#ifdef DEBUG_MACIISI_ADB
+                printk(KERN_DEBUG "maciisi_start: bus busy - aborting\n");
+#endif
+                return -EBUSY;
+        }
+
+        /* Okay, send */
+#ifdef DEBUG_MACIISI_ADB
+        printk(KERN_DEBUG "maciisi_start: sending\n");
+#endif
+        /* Set state to active */
+        via[B] |= TIP;
+        /* ACK off */
+        via[B] &= ~TACK;
+        /* Delay */
+        udelay(ADB_DELAY);
+        /* Shift out and send */
+        via[ACR] |= SR_OUT;
+        via[SR] = req->data[0];
+        data_index = 1;
+        /* ACK on */
+        via[B] |= TACK;
+        maciisi_state = sending;
+
+        return 0;
+}
+
+void
+maciisi_poll(void)
+{
+        unsigned long flags;
+
+        local_irq_save(flags);
+        if (via[IFR] & SR_INT) {
+                maciisi_interrupt(0, 0, 0);
+        }
+        else /* avoid calling this function too quickly in a loop */
+                udelay(ADB_DELAY);
+
+        local_irq_restore(flags);
+}
+
+/* Shift register interrupt - this is *supposed* to mean that the
+   register is either full or empty. In practice, I have no idea what
+   it means :( */
+static irqreturn_t
+maciisi_interrupt(int irq, void* arg, struct pt_regs* regs)
+{
+        int status;
+        struct adb_request *req;
+#ifdef DEBUG_MACIISI_ADB
+        static int dump_reply = 0;
+#endif
+        int i;
+        unsigned long flags;
+
+        local_irq_save(flags);
+
+        status = via[B] & (TIP|TREQ);
+#ifdef DEBUG_MACIISI_ADB
+        printk(KERN_DEBUG "state %d status %x ifr %x\n", maciisi_state, status, via[IFR]);
+#endif
+
+        if (!(via[IFR] & SR_INT)) {
+                /* Shouldn't happen, we hope */
+                printk(KERN_ERR "maciisi_interrupt: called without interrupt flag set\n");
+                local_irq_restore(flags);
+                return IRQ_NONE;
+        }
+
+        /* Clear the interrupt */
+        /* via[IFR] = SR_INT; */
+
+ switch_start:
+        switch (maciisi_state) {
+        case idle:
+                if (status & TIP)
+                        printk(KERN_ERR "maciisi_interrupt: state is idle but TIP asserted!\n");
+
+                if(!reading_reply)
+                        udelay(ADB_DELAY);
+                /* Shift in */
+                via[ACR] &= ~SR_OUT;
+                /* Signal start of frame */
+                via[B] |= TIP;
+                /* Clear the interrupt (throw this value on the floor, it's useless) */
+                tmp = via[SR];
+                /* ACK adb chip, high-low */
+                via[B] |= TACK;
+                udelay(ADB_DELAY);
+                via[B] &= ~TACK;
+                reply_len = 0;
+                maciisi_state = reading;
+                if (reading_reply) {
+                        reply_ptr = current_req->reply;
+                } else {
+                        reply_ptr = maciisi_rbuf;
+                }
+                break;
+
+        case sending:
+                /* via[SR]; */
+                /* Set ACK off */
+                via[B] &= ~TACK;
+                req = current_req;
+
+                if (!(status & TREQ)) {
+                        /* collision */
+                        printk(KERN_ERR "maciisi_interrupt: send collision\n");
+                        /* Set idle and input */
+                        via[ACR] &= ~SR_OUT;
+                        tmp = via[SR];
+                        via[B] &= ~TIP;
+                        /* Must re-send */
+                        reading_reply = 0;
+                        reply_len = 0;
+                        maciisi_state = idle;
+                        udelay(ADB_DELAY);
+                        /* process this now, because the IFR has been cleared */
+                        goto switch_start;
+                }
+
+                udelay(ADB_DELAY);
+
+                if (data_index >= req->nbytes) {
+                        /* Sent the whole packet, put the bus back in idle state */
+                        /* Shift in, we are about to read a reply (hopefully) */
+                        via[ACR] &= ~SR_OUT;
+                        tmp = via[SR];
+                        /* End of frame */
+                        via[B] &= ~TIP;
+                        req->sent = 1;
+                        maciisi_state = idle;
+                        if (req->reply_expected) {
+                                /* Note: only set this once we've
+                                   successfully sent the packet */
+                                reading_reply = 1;
+                        } else {
+                                current_req = req->next;
+                                if (req->done)
+                                        (*req->done)(req);
+                                /* Do any queued requests now */
+                                i = maciisi_start();
+                                if(i == 0 && need_sync) {
+                                        /* Packet needs to be synced */
+                                        maciisi_sync(current_req);
+                                }
+                                if(i != -EBUSY)
+                                        need_sync = 0;
+                        }
+                } else {
+                        /* Sending more stuff */
+                        /* Shift out */
+                        via[ACR] |= SR_OUT;
+                        /* Write */
+                        via[SR] = req->data[data_index++];
+                        /* Signal 'byte ready' */
+                        via[B] |= TACK;
+                }
+                break;
+
+        case reading:
+                /* Shift in */
+                /* via[ACR] &= ~SR_OUT; */ /* Not in 2.2 */
+                if (reply_len++ > 16) {
+                        printk(KERN_ERR "maciisi_interrupt: reply too long, aborting read\n");
+                        via[B] |= TACK;
+                        udelay(ADB_DELAY);
+                        via[B] &= ~(TACK|TIP);
+                        maciisi_state = idle;
+                        i = maciisi_start();
+                        if(i == 0 && need_sync) {
+                                /* Packet needs to be synced */
+                                maciisi_sync(current_req);
+                        }
+                        if(i != -EBUSY)
+                                need_sync = 0;
+                        break;
+                }
+                /* Read data */
+                *reply_ptr++ = via[SR];
+                status = via[B] & (TIP|TREQ);
+                /* ACK on/off */
+                via[B] |= TACK;
+                udelay(ADB_DELAY);
+                via[B] &= ~TACK;        
+                if (!(status & TREQ))
+                        break; /* more stuff to deal with */
+                
+                /* end of frame */
+                via[B] &= ~TIP;
+                tmp = via[SR]; /* That's what happens in 2.2 */
+                udelay(ADB_DELAY); /* Give controller time to recover */
+
+                /* end of packet, deal with it */
+                if (reading_reply) {
+                        req = current_req;
+                        req->reply_len = reply_ptr - req->reply;
+                        if (req->data[0] == ADB_PACKET) {
+                                /* Have to adjust the reply from ADB commands */
+                                if (req->reply_len <= 2 || (req->reply[1] & 2) != 0) {
+                                        /* the 0x2 bit indicates no response */
+                                        req->reply_len = 0;
+                                } else {
+                                        /* leave just the command and result bytes in the reply */
+                                        req->reply_len -= 2;
+                                        memmove(req->reply, req->reply + 2, req->reply_len);
+                                }
+                        }
+#ifdef DEBUG_MACIISI_ADB
+                        if (dump_reply) {
+                                int i;
+                                printk(KERN_DEBUG "maciisi_interrupt: reply is ");
+                                for (i = 0; i < req->reply_len; ++i)
+                                        printk(" %.2x", req->reply[i]);
+                                printk("\n");
+                        }
+#endif
+                        req->complete = 1;
+                        current_req = req->next;
+                        if (req->done)
+                                (*req->done)(req);
+                        /* Obviously, we got it */
+                        reading_reply = 0;
+                } else {
+                        maciisi_input(maciisi_rbuf, reply_ptr - maciisi_rbuf, regs);
+                }
+                maciisi_state = idle;
+                status = via[B] & (TIP|TREQ);
+                if (!(status & TREQ)) {
+                        /* Timeout?! More likely, another packet coming in already */
+#ifdef DEBUG_MACIISI_ADB
+                        printk(KERN_DEBUG "extra data after packet: status %x ifr %x\n",
+                               status, via[IFR]);
+#endif
+#if 0
+                        udelay(ADB_DELAY);
+                        via[B] |= TIP;
+
+                        maciisi_state = reading;
+                        reading_reply = 0;
+                        reply_ptr = maciisi_rbuf;
+#else
+                        /* Process the packet now */
+                        reading_reply = 0;
+                        goto switch_start;
+#endif
+                        /* We used to do this... but the controller might actually have data for us */
+                        /* maciisi_stfu(); */
+                }
+                else {
+                        /* Do any queued requests now if possible */
+                        i = maciisi_start();
+                        if(i == 0 && need_sync) {
+                                /* Packet needs to be synced */
+                                maciisi_sync(current_req);
+                        }
+                        if(i != -EBUSY)
+                                need_sync = 0;
+                }
+                break;
+
+        default:
+                printk("maciisi_interrupt: unknown maciisi_state %d?\n", maciisi_state);
+        }
+        local_irq_restore(flags);
+        return IRQ_HANDLED;
+}
+
+static void
+maciisi_input(unsigned char *buf, int nb, struct pt_regs *regs)
+{
+#ifdef DEBUG_MACIISI_ADB
+    int i;
+#endif
+
+    switch (buf[0]) {
+    case ADB_PACKET:
+            adb_input(buf+2, nb-2, regs, buf[1] & 0x40);
+            break;
+    default:
+#ifdef DEBUG_MACIISI_ADB
+            printk(KERN_DEBUG "data from IIsi ADB (%d bytes):", nb);
+            for (i = 0; i < nb; ++i)
+                    printk(" %.2x", buf[i]);
+            printk("\n");
+#endif
+            break;
+    }
+}