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author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/macintosh/via-maciisi.c | |
download | kernel_samsung_tuna-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip kernel_samsung_tuna-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz kernel_samsung_tuna-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.bz2 |
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'drivers/macintosh/via-maciisi.c')
-rw-r--r-- | drivers/macintosh/via-maciisi.c | 661 |
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 0000000..a196697 --- /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; + } +} |