--- /dev/null
+/*
+ * 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/adb.h>
+#include <linux/cuda.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <asm/macintosh.h>
+#include <asm/macints.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;
+static struct adb_request* last_req;
+static unsigned char maciisi_rbuf[16];
+static unsigned char *reply_ptr;
+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);
+static void maciisi_input(unsigned char *buf, int nb);
+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, 0, "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");
+}
+
+int
+maciisi_request(struct adb_request *req, void (*done)(struct adb_request *),
+ int nbytes, ...)
+{
+ va_list list;
+ int i;
+
+ req->nbytes = nbytes;
+ req->done = done;
+ req->reply_expected = 0;
+ va_start(list, nbytes);
+ for (i = 0; i < nbytes; i++)
+ req->data[i++] = va_arg(list, int);
+ va_end(list);
+
+ return maciisi_send_request(req, 1);
+}
+
+/* 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 = NULL;
+ 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, NULL);
+ }
+ 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)
+{
+ 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);
+ }
+ 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)
+{
+#ifdef DEBUG_MACIISI_ADB
+ int i;
+#endif
+
+ switch (buf[0]) {
+ case ADB_PACKET:
+ adb_input(buf+2, nb-2, 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;
+ }
+}
Code Review / kvmfornfv.git / blobdiff