[net-next-2.6.git] / drivers / macintosh / via-cuda.c

/*
 * Device driver for the via-cuda on Apple Powermacs.
 *
 * The VIA (versatile interface adapter) interfaces to the CUDA,
 * a 6805 microprocessor core which controls the ADB (Apple Desktop
 * Bus) which connects to the keyboard and mouse.  The CUDA also
 * controls system power and the RTC (real time clock) chip.
 *
 * Copyright (C) 1996 Paul Mackerras.
 */
#include <stdarg.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/adb.h>
#include <linux/cuda.h>
#include <linux/spinlock.h>
#include <linux/interrupt.h>
#ifdef CONFIG_PPC
#include <asm/prom.h>
#include <asm/machdep.h>
#else
#include <asm/macintosh.h>
#include <asm/macints.h>
#include <asm/mac_via.h>
#endif
#include <asm/io.h>
#include <asm/system.h>
#include <linux/init.h>

static volatile unsigned char __iomem *via;
static DEFINE_SPINLOCK(cuda_lock);

/* VIA registers - spaced 0x200 bytes apart */
#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 T1CL		(4*RS)		/* Timer 1 ctr/latch (low 8 bits) */
#define T1CH		(5*RS)		/* Timer 1 counter (high 8 bits) */
#define T1LL		(6*RS)		/* Timer 1 latch (low 8 bits) */
#define T1LH		(7*RS)		/* Timer 1 latch (high 8 bits) */
#define T2CL		(8*RS)		/* Timer 2 ctr/latch (low 8 bits) */
#define T2CH		(9*RS)		/* Timer 2 counter (high 8 bits) */
#define SR		(10*RS)		/* Shift register */
#define ACR		(11*RS)		/* Auxiliary control register */
#define PCR		(12*RS)		/* Peripheral control register */
#define IFR		(13*RS)		/* Interrupt flag register */
#define IER		(14*RS)		/* Interrupt enable register */
#define ANH		(15*RS)		/* A-side data, no handshake */

/* 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) */

/* 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 */

static enum cuda_state {
    idle,
    sent_first_byte,
    sending,
    reading,
    read_done,
    awaiting_reply
} cuda_state;

static struct adb_request *current_req;
static struct adb_request *last_req;
static unsigned char cuda_rbuf[16];
static unsigned char *reply_ptr;
static int reading_reply;
static int data_index;
static int cuda_irq;
#ifdef CONFIG_PPC
static struct device_node *vias;
#endif
static int cuda_fully_inited;

#ifdef CONFIG_ADB
static int cuda_probe(void);
static int cuda_send_request(struct adb_request *req, int sync);
static int cuda_adb_autopoll(int devs);
static int cuda_reset_adb_bus(void);
#endif /* CONFIG_ADB */

static int cuda_init_via(void);
static void cuda_start(void);
static irqreturn_t cuda_interrupt(int irq, void *arg);
static void cuda_input(unsigned char *buf, int nb);
void cuda_poll(void);
static int cuda_write(struct adb_request *req);

int cuda_request(struct adb_request *req,
		 void (*done)(struct adb_request *), int nbytes, ...);

#ifdef CONFIG_ADB
struct adb_driver via_cuda_driver = {
	.name         = "CUDA",
	.probe        = cuda_probe,
	.send_request = cuda_send_request,
	.autopoll     = cuda_adb_autopoll,
	.poll         = cuda_poll,
	.reset_bus    = cuda_reset_adb_bus,
};
#endif /* CONFIG_ADB */

#ifdef CONFIG_MAC
int __init find_via_cuda(void)
{
    struct adb_request req;
    int err;

    if (macintosh_config->adb_type != MAC_ADB_CUDA)
	return 0;

    via = via1;
    cuda_state = idle;

    err = cuda_init_via();
    if (err) {
	printk(KERN_ERR "cuda_init_via() failed\n");
	via = NULL;
	return 0;
    }

    /* enable autopoll */
    cuda_request(&req, NULL, 3, CUDA_PACKET, CUDA_AUTOPOLL, 1);
    while (!req.complete)
	cuda_poll();

    return 1;
}
#else
int __init find_via_cuda(void)
{
    struct adb_request req;
    phys_addr_t taddr;
    const u32 *reg;
    int err;

    if (vias != 0)
	return 1;
    vias = of_find_node_by_name(NULL, "via-cuda");
    if (vias == 0)
	return 0;

    reg = of_get_property(vias, "reg", NULL);
    if (reg == NULL) {
	    printk(KERN_ERR "via-cuda: No \"reg\" property !\n");
	    goto fail;
    }
    taddr = of_translate_address(vias, reg);
    if (taddr == 0) {
	    printk(KERN_ERR "via-cuda: Can't translate address !\n");
	    goto fail;
    }
    via = ioremap(taddr, 0x2000);
    if (via == NULL) {
	    printk(KERN_ERR "via-cuda: Can't map address !\n");
	    goto fail;
    }

    cuda_state = idle;
    sys_ctrler = SYS_CTRLER_CUDA;

    err = cuda_init_via();
    if (err) {
	printk(KERN_ERR "cuda_init_via() failed\n");
	via = NULL;
	return 0;
    }

    /* Clear and enable interrupts, but only on PPC. On 68K it's done  */
    /* for us by the main VIA driver in arch/m68k/mac/via.c        */

    out_8(&via[IFR], 0x7f);	/* clear interrupts by writing 1s */
    out_8(&via[IER], IER_SET|SR_INT); /* enable interrupt from SR */

    /* enable autopoll */
    cuda_request(&req, NULL, 3, CUDA_PACKET, CUDA_AUTOPOLL, 1);
    while (!req.complete)
	cuda_poll();

    return 1;

 fail:
    of_node_put(vias);
    vias = NULL;
    return 0;
}
#endif /* !defined CONFIG_MAC */

static int __init via_cuda_start(void)
{
    if (via == NULL)
	return -ENODEV;

#ifdef CONFIG_MAC
    cuda_irq = IRQ_MAC_ADB;
#else
    cuda_irq = irq_of_parse_and_map(vias, 0);
    if (cuda_irq == NO_IRQ) {
	printk(KERN_ERR "via-cuda: can't map interrupts for %s\n",
	       vias->full_name);
	return -ENODEV;
    }
#endif

    if (request_irq(cuda_irq, cuda_interrupt, 0, "ADB", cuda_interrupt)) {
	printk(KERN_ERR "via-cuda: can't request irq %d\n", cuda_irq);
	return -EAGAIN;
    }

    printk("Macintosh CUDA driver v0.5 for Unified ADB.\n");

    cuda_fully_inited = 1;
    return 0;
}

device_initcall(via_cuda_start);

#ifdef CONFIG_ADB
static int
cuda_probe(void)
{
#ifdef CONFIG_PPC
    if (sys_ctrler != SYS_CTRLER_CUDA)
	return -ENODEV;
#else
    if (macintosh_config->adb_type != MAC_ADB_CUDA)
	return -ENODEV;
#endif
    if (via == NULL)
	return -ENODEV;
    return 0;
}
#endif /* CONFIG_ADB */

#define WAIT_FOR(cond, what)					\
    do {                                                        \
    	int x;							\
	for (x = 1000; !(cond); --x) {				\
	    if (x == 0) {					\
		printk("Timeout waiting for " what "\n");	\
		return -ENXIO;					\
	    }							\
	    udelay(100);					\
	}							\
    } while (0)

static int
cuda_init_via(void)
{
    out_8(&via[DIRB], (in_8(&via[DIRB]) | TACK | TIP) & ~TREQ);	/* TACK & TIP out */
    out_8(&via[B], in_8(&via[B]) | TACK | TIP);			/* negate them */
    out_8(&via[ACR] ,(in_8(&via[ACR]) & ~SR_CTRL) | SR_EXT);	/* SR data in */
    (void)in_8(&via[SR]);						/* clear any left-over data */
#ifdef CONFIG_PPC
    out_8(&via[IER], 0x7f);					/* disable interrupts from VIA */
    (void)in_8(&via[IER]);
#else
    out_8(&via[IER], SR_INT);					/* disable SR interrupt from VIA */
#endif

    /* delay 4ms and then clear any pending interrupt */
    mdelay(4);
    (void)in_8(&via[SR]);
    out_8(&via[IFR], SR_INT);

    /* sync with the CUDA - assert TACK without TIP */
    out_8(&via[B], in_8(&via[B]) & ~TACK);

    /* wait for the CUDA to assert TREQ in response */
    WAIT_FOR((in_8(&via[B]) & TREQ) == 0, "CUDA response to sync");

    /* wait for the interrupt and then clear it */
    WAIT_FOR(in_8(&via[IFR]) & SR_INT, "CUDA response to sync (2)");
    (void)in_8(&via[SR]);
    out_8(&via[IFR], SR_INT);

    /* finish the sync by negating TACK */
    out_8(&via[B], in_8(&via[B]) | TACK);

    /* wait for the CUDA to negate TREQ and the corresponding interrupt */
    WAIT_FOR(in_8(&via[B]) & TREQ, "CUDA response to sync (3)");
    WAIT_FOR(in_8(&via[IFR]) & SR_INT, "CUDA response to sync (4)");
    (void)in_8(&via[SR]);
    out_8(&via[IFR], SR_INT);
    out_8(&via[B], in_8(&via[B]) | TIP);	/* should be unnecessary */

    return 0;
}

#ifdef CONFIG_ADB
/* Send an ADB command */
static int
cuda_send_request(struct adb_request *req, int sync)
{
    int i;

    if ((via == NULL) || !cuda_fully_inited) {
	req->complete = 1;
	return -ENXIO;
    }
  
    req->reply_expected = 1;

    i = cuda_write(req);
    if (i)
	return i;

    if (sync) {
	while (!req->complete)
	    cuda_poll();
    }
    return 0;
}


/* Enable/disable autopolling */
static int
cuda_adb_autopoll(int devs)
{
    struct adb_request req;

    if ((via == NULL) || !cuda_fully_inited)
	return -ENXIO;

    cuda_request(&req, NULL, 3, CUDA_PACKET, CUDA_AUTOPOLL, (devs? 1: 0));
    while (!req.complete)
	cuda_poll();
    return 0;
}

/* Reset adb bus - how do we do this?? */
static int
cuda_reset_adb_bus(void)
{
    struct adb_request req;

    if ((via == NULL) || !cuda_fully_inited)
	return -ENXIO;

    cuda_request(&req, NULL, 2, ADB_PACKET, 0);		/* maybe? */
    while (!req.complete)
	cuda_poll();
    return 0;
}
#endif /* CONFIG_ADB */
/* Construct and send a cuda request */
int
cuda_request(struct adb_request *req, void (*done)(struct adb_request *),
	     int nbytes, ...)
{
    va_list list;
    int i;

    if (via == NULL) {
	req->complete = 1;
	return -ENXIO;
    }

    req->nbytes = nbytes;
    req->done = done;
    va_start(list, nbytes);
    for (i = 0; i < nbytes; ++i)
	req->data[i] = va_arg(list, int);
    va_end(list);
    req->reply_expected = 1;
    return cuda_write(req);
}

static int
cuda_write(struct adb_request *req)
{
    unsigned long flags;

    if (req->nbytes < 2 || req->data[0] > CUDA_PACKET) {
	req->complete = 1;
	return -EINVAL;
    }
    req->next = NULL;
    req->sent = 0;
    req->complete = 0;
    req->reply_len = 0;

    spin_lock_irqsave(&cuda_lock, flags);
    if (current_req != 0) {
	last_req->next = req;
	last_req = req;
    } else {
	current_req = req;
	last_req = req;
	if (cuda_state == idle)
	    cuda_start();
    }
    spin_unlock_irqrestore(&cuda_lock, flags);

    return 0;
}

static void
cuda_start(void)
{
    struct adb_request *req;

    /* assert cuda_state == idle */
    /* get the packet to send */
    req = current_req;
    if (req == 0)
	return;
    if ((in_8(&via[B]) & TREQ) == 0)
	return;			/* a byte is coming in from the CUDA */

    /* set the shift register to shift out and send a byte */
    out_8(&via[ACR], in_8(&via[ACR]) | SR_OUT);
    out_8(&via[SR], req->data[0]);
    out_8(&via[B], in_8(&via[B]) & ~TIP);
    cuda_state = sent_first_byte;
}

void
cuda_poll(void)
{
    /* cuda_interrupt only takes a normal lock, we disable
     * interrupts here to avoid re-entering and thus deadlocking.
     */
    if (cuda_irq)
	disable_irq(cuda_irq);
    cuda_interrupt(0, NULL);
    if (cuda_irq)
	enable_irq(cuda_irq);
}

static irqreturn_t
cuda_interrupt(int irq, void *arg)
{
    int status;
    struct adb_request *req = NULL;
    unsigned char ibuf[16];
    int ibuf_len = 0;
    int complete = 0;
    
    spin_lock(&cuda_lock);

    /* On powermacs, this handler is registered for the VIA IRQ. But they use
     * just the shift register IRQ -- other VIA interrupt sources are disabled.
     * On m68k macs, the VIA IRQ sources are dispatched individually. Unless
     * we are polling, the shift register IRQ flag has already been cleared.
     */

#ifdef CONFIG_MAC
    if (!arg)
#endif
    {
        if ((in_8(&via[IFR]) & SR_INT) == 0) {
            spin_unlock(&cuda_lock);
            return IRQ_NONE;
        } else {
            out_8(&via[IFR], SR_INT);
        }
    }
    
    status = (~in_8(&via[B]) & (TIP|TREQ)) | (in_8(&via[ACR]) & SR_OUT);
    /* printk("cuda_interrupt: state=%d status=%x\n", cuda_state, status); */
    switch (cuda_state) {
    case idle:
	/* CUDA has sent us the first byte of data - unsolicited */
	if (status != TREQ)
	    printk("cuda: state=idle, status=%x\n", status);
	(void)in_8(&via[SR]);
	out_8(&via[B], in_8(&via[B]) & ~TIP);
	cuda_state = reading;
	reply_ptr = cuda_rbuf;
	reading_reply = 0;
	break;

    case awaiting_reply:
	/* CUDA has sent us the first byte of data of a reply */
	if (status != TREQ)
	    printk("cuda: state=awaiting_reply, status=%x\n", status);
	(void)in_8(&via[SR]);
	out_8(&via[B], in_8(&via[B]) & ~TIP);
	cuda_state = reading;
	reply_ptr = current_req->reply;
	reading_reply = 1;
	break;

    case sent_first_byte:
	if (status == TREQ + TIP + SR_OUT) {
	    /* collision */
	    out_8(&via[ACR], in_8(&via[ACR]) & ~SR_OUT);
	    (void)in_8(&via[SR]);
	    out_8(&via[B], in_8(&via[B]) | TIP | TACK);
	    cuda_state = idle;
	} else {
	    /* assert status == TIP + SR_OUT */
	    if (status != TIP + SR_OUT)
		printk("cuda: state=sent_first_byte status=%x\n", status);
	    out_8(&via[SR], current_req->data[1]);
	    out_8(&via[B], in_8(&via[B]) ^ TACK);
	    data_index = 2;
	    cuda_state = sending;
	}
	break;

    case sending:
	req = current_req;
	if (data_index >= req->nbytes) {
	    out_8(&via[ACR], in_8(&via[ACR]) & ~SR_OUT);
	    (void)in_8(&via[SR]);
	    out_8(&via[B], in_8(&via[B]) | TACK | TIP);
	    req->sent = 1;
	    if (req->reply_expected) {
		cuda_state = awaiting_reply;
	    } else {
		current_req = req->next;
		complete = 1;
		/* not sure about this */
		cuda_state = idle;
		cuda_start();
	    }
	} else {
	    out_8(&via[SR], req->data[data_index++]);
	    out_8(&via[B], in_8(&via[B]) ^ TACK);
	}
	break;

    case reading:
	*reply_ptr++ = in_8(&via[SR]);
	if (status == TIP) {
	    /* that's all folks */
	    out_8(&via[B], in_8(&via[B]) | TACK | TIP);
	    cuda_state = read_done;
	} else {
	    /* assert status == TIP | TREQ */
	    if (status != TIP + TREQ)
		printk("cuda: state=reading status=%x\n", status);
	    out_8(&via[B], in_8(&via[B]) ^ TACK);
	}
	break;

    case read_done:
	(void)in_8(&via[SR]);
	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);
		}
	    }
	    current_req = req->next;
	    complete = 1;
	} else {
	    /* This is tricky. We must break the spinlock to call
	     * cuda_input. However, doing so means we might get
	     * re-entered from another CPU getting an interrupt
	     * or calling cuda_poll(). I ended up using the stack
	     * (it's only for 16 bytes) and moving the actual
	     * call to cuda_input to outside of the lock.
	     */
	    ibuf_len = reply_ptr - cuda_rbuf;
	    memcpy(ibuf, cuda_rbuf, ibuf_len);
	}
	if (status == TREQ) {
	    out_8(&via[B], in_8(&via[B]) & ~TIP);
	    cuda_state = reading;
	    reply_ptr = cuda_rbuf;
	    reading_reply = 0;
	} else {
	    cuda_state = idle;
	    cuda_start();
	}
	break;

    default:
	printk("cuda_interrupt: unknown cuda_state %d?\n", cuda_state);
    }
    spin_unlock(&cuda_lock);
    if (complete && req) {
    	void (*done)(struct adb_request *) = req->done;
    	mb();
    	req->complete = 1;
    	/* Here, we assume that if the request has a done member, the
    	 * struct request will survive to setting req->complete to 1
    	 */
    	if (done)
		(*done)(req);
    }
    if (ibuf_len)
	cuda_input(ibuf, ibuf_len);
    return IRQ_HANDLED;
}

static void
cuda_input(unsigned char *buf, int nb)
{
    int i;

    switch (buf[0]) {
    case ADB_PACKET:
#ifdef CONFIG_XMON
	if (nb == 5 && buf[2] == 0x2c) {
	    extern int xmon_wants_key, xmon_adb_keycode;
	    if (xmon_wants_key) {
		xmon_adb_keycode = buf[3];
		return;
	    }
	}
#endif /* CONFIG_XMON */
#ifdef CONFIG_ADB
	adb_input(buf+2, nb-2, buf[1] & 0x40);
#endif /* CONFIG_ADB */
	break;

    default:
	printk("data from cuda (%d bytes):", nb);
	for (i = 0; i < nb; ++i)
	    printk(" %.2x", buf[i]);
	printk("\n");
    }
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Device driver for the via-cuda on Apple Powermacs.
	3	*
	4	* The VIA (versatile interface adapter) interfaces to the CUDA,
	5	* a 6805 microprocessor core which controls the ADB (Apple Desktop
	6	* Bus) which connects to the keyboard and mouse. The CUDA also
	7	* controls system power and the RTC (real time clock) chip.
	8	*
	9	* Copyright (C) 1996 Paul Mackerras.
	10	*/
	11	#include <stdarg.h>
1da177e4 LT	12	#include <linux/types.h>
	13	#include <linux/errno.h>
	14	#include <linux/kernel.h>
	15	#include <linux/delay.h>
1da177e4 LT	16	#include <linux/adb.h>
	17	#include <linux/cuda.h>
	18	#include <linux/spinlock.h>
	19	#include <linux/interrupt.h>
	20	#ifdef CONFIG_PPC
	21	#include <asm/prom.h>
	22	#include <asm/machdep.h>
	23	#else
	24	#include <asm/macintosh.h>
	25	#include <asm/macints.h>
1da177e4 LT	26	#include <asm/mac_via.h>
	27	#endif
	28	#include <asm/io.h>
	29	#include <asm/system.h>
	30	#include <linux/init.h>
	31
	32	static volatile unsigned char __iomem *via;
	33	static DEFINE_SPINLOCK(cuda_lock);
	34
1da177e4 LT	35	/* VIA registers - spaced 0x200 bytes apart */
	36	#define RS 0x200 /* skip between registers */
	37	#define B 0 /* B-side data */
	38	#define A RS /* A-side data */
	39	#define DIRB (2RS) / B-side direction (1=output) */
	40	#define DIRA (3RS) / A-side direction (1=output) */
	41	#define T1CL (4RS) / Timer 1 ctr/latch (low 8 bits) */
	42	#define T1CH (5RS) / Timer 1 counter (high 8 bits) */
	43	#define T1LL (6RS) / Timer 1 latch (low 8 bits) */
	44	#define T1LH (7RS) / Timer 1 latch (high 8 bits) */
	45	#define T2CL (8RS) / Timer 2 ctr/latch (low 8 bits) */
	46	#define T2CH (9RS) / Timer 2 counter (high 8 bits) */
	47	#define SR (10RS) / Shift register */
	48	#define ACR (11RS) / Auxiliary control register */
	49	#define PCR (12RS) / Peripheral control register */
	50	#define IFR (13RS) / Interrupt flag register */
	51	#define IER (14RS) / Interrupt enable register */
	52	#define ANH (15RS) / A-side data, no handshake */
	53
	54	/* Bits in B data register: all active low */
	55	#define TREQ 0x08 /* Transfer request (input) */
	56	#define TACK 0x10 /* Transfer acknowledge (output) */
	57	#define TIP 0x20 /* Transfer in progress (output) */
	58
	59	/* Bits in ACR */
	60	#define SR_CTRL 0x1c /* Shift register control bits */
	61	#define SR_EXT 0x0c /* Shift on external clock */
	62	#define SR_OUT 0x10 /* Shift out if 1 */
	63
	64	/* Bits in IFR and IER */
	65	#define IER_SET 0x80 /* set bits in IER */
	66	#define IER_CLR 0 /* clear bits in IER */
	67	#define SR_INT 0x04 /* Shift register full/empty */
	68
	69	static enum cuda_state {
	70	idle,
	71	sent_first_byte,
	72	sending,
	73	reading,
	74	read_done,
	75	awaiting_reply
	76	} cuda_state;
	77
	78	static struct adb_request *current_req;
	79	static struct adb_request *last_req;
	80	static unsigned char cuda_rbuf[16];
	81	static unsigned char *reply_ptr;
	82	static int reading_reply;
	83	static int data_index;
0251c38c	84	static int cuda_irq;
1da177e4 LT	85	#ifdef CONFIG_PPC
	86	static struct device_node *vias;
	87	#endif
87275856	88	static int cuda_fully_inited;
1da177e4 LT	89
	90	#ifdef CONFIG_ADB
	91	static int cuda_probe(void);
1da177e4 LT	92	static int cuda_send_request(struct adb_request *req, int sync);
	93	static int cuda_adb_autopoll(int devs);
	94	static int cuda_reset_adb_bus(void);
	95	#endif /* CONFIG_ADB */
	96
	97	static int cuda_init_via(void);
	98	static void cuda_start(void);
7d12e780 DH	99	static irqreturn_t cuda_interrupt(int irq, void *arg);
7d12e780 DH	100	static void cuda_input(unsigned char *buf, int nb);
1da177e4 LT	101	void cuda_poll(void);
	102	static int cuda_write(struct adb_request *req);
	103
	104	int cuda_request(struct adb_request *req,
	105	void (done)(struct adb_request ), int nbytes, ...);
	106
	107	#ifdef CONFIG_ADB
	108	struct adb_driver via_cuda_driver = {
18814ee8 FT	109	.name = "CUDA",
	110	.probe = cuda_probe,
	111	.send_request = cuda_send_request,
	112	.autopoll = cuda_adb_autopoll,
	113	.poll = cuda_poll,
	114	.reset_bus = cuda_reset_adb_bus,
1da177e4 LT	115	};
	116	#endif /* CONFIG_ADB */
	117
18814ee8 FT	118	#ifdef CONFIG_MAC
	119	int __init find_via_cuda(void)
	120	{
	121	struct adb_request req;
	122	int err;
	123
	124	if (macintosh_config->adb_type != MAC_ADB_CUDA)
	125	return 0;
	126
	127	via = via1;
	128	cuda_state = idle;
	129
	130	err = cuda_init_via();
	131	if (err) {
	132	printk(KERN_ERR "cuda_init_via() failed\n");
	133	via = NULL;
	134	return 0;
	135	}
	136
	137	/* enable autopoll */
	138	cuda_request(&req, NULL, 3, CUDA_PACKET, CUDA_AUTOPOLL, 1);
	139	while (!req.complete)
	140	cuda_poll();
	141
	142	return 1;
	143	}
	144	#else
51d3082f	145	int __init find_via_cuda(void)
1da177e4	146	{
1da177e4	147	struct adb_request req;
51d3082f	148	phys_addr_t taddr;
018a3d1d	149	const u32 *reg;
51d3082f	150	int err;
1da177e4 LT	151
	152	if (vias != 0)
	153	return 1;
51d3082f	154	vias = of_find_node_by_name(NULL, "via-cuda");
1da177e4 LT	155	if (vias == 0)
1da177e4 LT	156	return 0;
1da177e4	157
01b2726d	158	reg = of_get_property(vias, "reg", NULL);
51d3082f BH	159	if (reg == NULL) {
	160	printk(KERN_ERR "via-cuda: No \"reg\" property !\n");
	161	goto fail;
	162	}
	163	taddr = of_translate_address(vias, reg);
	164	if (taddr == 0) {
	165	printk(KERN_ERR "via-cuda: Can't translate address !\n");
	166	goto fail;
	167	}
	168	via = ioremap(taddr, 0x2000);
	169	if (via == NULL) {
	170	printk(KERN_ERR "via-cuda: Can't map address !\n");
	171	goto fail;
1da177e4	172	}
1da177e4 LT	173
	174	cuda_state = idle;
	175	sys_ctrler = SYS_CTRLER_CUDA;
	176
	177	err = cuda_init_via();
	178	if (err) {
	179	printk(KERN_ERR "cuda_init_via() failed\n");
	180	via = NULL;
	181	return 0;
	182	}
	183
	184	/* Clear and enable interrupts, but only on PPC. On 68K it's done */
	185	/* for us by the main VIA driver in arch/m68k/mac/via.c */
	186
1da177e4 LT	187	out_8(&via[IFR], 0x7f); /* clear interrupts by writing 1s */
1da177e4 LT	188	out_8(&via[IER], IER_SET\|SR_INT); /* enable interrupt from SR */
1da177e4 LT	189
	190	/* enable autopoll */
	191	cuda_request(&req, NULL, 3, CUDA_PACKET, CUDA_AUTOPOLL, 1);
	192	while (!req.complete)
	193	cuda_poll();
	194
	195	return 1;
51d3082f BH	196
	197	fail:
	198	of_node_put(vias);
	199	vias = NULL;
	200	return 0;
1da177e4	201	}
18814ee8	202	#endif /* !defined CONFIG_MAC */
1da177e4 LT	203
	204	static int __init via_cuda_start(void)
	205	{
	206	if (via == NULL)
	207	return -ENODEV;
	208
0ebfff14	209	#ifdef CONFIG_MAC
0251c38c	210	cuda_irq = IRQ_MAC_ADB;
18814ee8	211	#else
0251c38c FT	212	cuda_irq = irq_of_parse_and_map(vias, 0);
0251c38c FT	213	if (cuda_irq == NO_IRQ) {
0ebfff14 BH	214	printk(KERN_ERR "via-cuda: can't map interrupts for %s\n",
	215	vias->full_name);
	216	return -ENODEV;
	217	}
18814ee8	218	#endif
0ebfff14	219
0251c38c FT	220	if (request_irq(cuda_irq, cuda_interrupt, 0, "ADB", cuda_interrupt)) {
0251c38c FT	221	printk(KERN_ERR "via-cuda: can't request irq %d\n", cuda_irq);
1da177e4 LT	222	return -EAGAIN;
	223	}
	224
	225	printk("Macintosh CUDA driver v0.5 for Unified ADB.\n");
	226
	227	cuda_fully_inited = 1;
	228	return 0;
	229	}
	230
	231	device_initcall(via_cuda_start);
	232
	233	#ifdef CONFIG_ADB
	234	static int
	235	cuda_probe(void)
	236	{
	237	#ifdef CONFIG_PPC
	238	if (sys_ctrler != SYS_CTRLER_CUDA)
	239	return -ENODEV;
	240	#else
	241	if (macintosh_config->adb_type != MAC_ADB_CUDA)
	242	return -ENODEV;
1da177e4	243	#endif
1da177e4 LT	244	if (via == NULL)
	245	return -ENODEV;
	246	return 0;
1da177e4 LT	247	}
	248	#endif /* CONFIG_ADB */
	249
	250	#define WAIT_FOR(cond, what) \
	251	do { \
	252	int x; \
	253	for (x = 1000; !(cond); --x) { \
	254	if (x == 0) { \
	255	printk("Timeout waiting for " what "\n"); \
	256	return -ENXIO; \
	257	} \
	258	udelay(100); \
	259	} \
	260	} while (0)
	261
	262	static int
	263	cuda_init_via(void)
	264	{
	265	out_8(&via[DIRB], (in_8(&via[DIRB]) \| TACK \| TIP) & ~TREQ); /* TACK & TIP out */
	266	out_8(&via[B], in_8(&via[B]) \| TACK \| TIP); /* negate them */
	267	out_8(&via[ACR] ,(in_8(&via[ACR]) & ~SR_CTRL) \| SR_EXT); /* SR data in */
	268	(void)in_8(&via[SR]); /* clear any left-over data */
0251c38c	269	#ifdef CONFIG_PPC
1da177e4 LT	270	out_8(&via[IER], 0x7f); /* disable interrupts from VIA */
1da177e4 LT	271	(void)in_8(&via[IER]);
0251c38c FT	272	#else
0251c38c FT	273	out_8(&via[IER], SR_INT); /* disable SR interrupt from VIA */
1da177e4 LT	274	#endif
	275
	276	/* delay 4ms and then clear any pending interrupt */
	277	mdelay(4);
	278	(void)in_8(&via[SR]);
0251c38c	279	out_8(&via[IFR], SR_INT);
1da177e4 LT	280
	281	/* sync with the CUDA - assert TACK without TIP */
	282	out_8(&via[B], in_8(&via[B]) & ~TACK);
	283
	284	/* wait for the CUDA to assert TREQ in response */
	285	WAIT_FOR((in_8(&via[B]) & TREQ) == 0, "CUDA response to sync");
	286
	287	/* wait for the interrupt and then clear it */
	288	WAIT_FOR(in_8(&via[IFR]) & SR_INT, "CUDA response to sync (2)");
	289	(void)in_8(&via[SR]);
0251c38c	290	out_8(&via[IFR], SR_INT);
1da177e4 LT	291
	292	/* finish the sync by negating TACK */
	293	out_8(&via[B], in_8(&via[B]) \| TACK);
	294
	295	/* wait for the CUDA to negate TREQ and the corresponding interrupt */
	296	WAIT_FOR(in_8(&via[B]) & TREQ, "CUDA response to sync (3)");
	297	WAIT_FOR(in_8(&via[IFR]) & SR_INT, "CUDA response to sync (4)");
	298	(void)in_8(&via[SR]);
0251c38c	299	out_8(&via[IFR], SR_INT);
1da177e4 LT	300	out_8(&via[B], in_8(&via[B]) \| TIP); /* should be unnecessary */
	301
	302	return 0;
	303	}
	304
	305	#ifdef CONFIG_ADB
	306	/* Send an ADB command */
	307	static int
	308	cuda_send_request(struct adb_request *req, int sync)
	309	{
	310	int i;
	311
	312	if ((via == NULL) \|\| !cuda_fully_inited) {
	313	req->complete = 1;
	314	return -ENXIO;
	315	}
	316
	317	req->reply_expected = 1;
	318
	319	i = cuda_write(req);
	320	if (i)
	321	return i;
	322
	323	if (sync) {
	324	while (!req->complete)
	325	cuda_poll();
	326	}
	327	return 0;
	328	}
	329
	330
	331	/* Enable/disable autopolling */
	332	static int
	333	cuda_adb_autopoll(int devs)
	334	{
	335	struct adb_request req;
	336
	337	if ((via == NULL) \|\| !cuda_fully_inited)
	338	return -ENXIO;
	339
	340	cuda_request(&req, NULL, 3, CUDA_PACKET, CUDA_AUTOPOLL, (devs? 1: 0));
	341	while (!req.complete)
	342	cuda_poll();
	343	return 0;
	344	}
	345
	346	/* Reset adb bus - how do we do this?? */
	347	static int
	348	cuda_reset_adb_bus(void)
	349	{
	350	struct adb_request req;
	351
	352	if ((via == NULL) \|\| !cuda_fully_inited)
	353	return -ENXIO;
	354
	355	cuda_request(&req, NULL, 2, ADB_PACKET, 0); /* maybe? */
	356	while (!req.complete)
	357	cuda_poll();
	358	return 0;
	359	}
	360	#endif /* CONFIG_ADB */
	361	/* Construct and send a cuda request */
	362	int
	363	cuda_request(struct adb_request req, void (done)(struct adb_request *),
364	int nbytes, ...)
365	{
366	va_list list;
367	int i;
368
369	if (via == NULL) {
370	req->complete = 1;
371	return -ENXIO;
372	}
373
374	req->nbytes = nbytes;
375	req->done = done;
376	va_start(list, nbytes);
377	for (i = 0; i < nbytes; ++i)
378	req->data[i] = va_arg(list, int);
379	va_end(list);
380	req->reply_expected = 1;
381	return cuda_write(req);
382	}
383
384	static int
385	cuda_write(struct adb_request *req)
386	{
387	unsigned long flags;
388
389	if (req->nbytes < 2 \|\| req->data[0] > CUDA_PACKET) {
390	req->complete = 1;
391	return -EINVAL;
392	}
393	req->next = NULL;
394	req->sent = 0;
395	req->complete = 0;
396	req->reply_len = 0;
397
398	spin_lock_irqsave(&cuda_lock, flags);
399	if (current_req != 0) {
400	last_req->next = req;
401	last_req = req;
402	} else {
403	current_req = req;
404	last_req = req;
405	if (cuda_state == idle)
406	cuda_start();
407	}
408	spin_unlock_irqrestore(&cuda_lock, flags);
409
410	return 0;
411	}
412
413	static void
414	cuda_start(void)
415	{
416	struct adb_request *req;
417
418	/* assert cuda_state == idle */
419	/* get the packet to send */
420	req = current_req;
421	if (req == 0)
422	return;
423	if ((in_8(&via[B]) & TREQ) == 0)
424	return; /* a byte is coming in from the CUDA */
425
426	/* set the shift register to shift out and send a byte */
427	out_8(&via[ACR], in_8(&via[ACR]) \| SR_OUT);
428	out_8(&via[SR], req->data[0]);
429	out_8(&via[B], in_8(&via[B]) & ~TIP);
430	cuda_state = sent_first_byte;
431	}
432
433	void
434	cuda_poll(void)
435	{
1da177e4 LT	436	/* cuda_interrupt only takes a normal lock, we disable
1da177e4 LT	437	* interrupts here to avoid re-entering and thus deadlocking.
1da177e4	438	*/
18814ee8 FT	439	if (cuda_irq)
18814ee8 FT	440	disable_irq(cuda_irq);
49f19ce4	441	cuda_interrupt(0, NULL);
18814ee8 FT	442	if (cuda_irq)
18814ee8 FT	443	enable_irq(cuda_irq);
1da177e4 LT	444	}
	445
	446	static irqreturn_t
7d12e780	447	cuda_interrupt(int irq, void *arg)
1da177e4 LT	448	{
	449	int status;
	450	struct adb_request *req = NULL;
	451	unsigned char ibuf[16];
	452	int ibuf_len = 0;
	453	int complete = 0;
1da177e4 LT	454
	455	spin_lock(&cuda_lock);
	456
18814ee8	457	/* On powermacs, this handler is registered for the VIA IRQ. But they use
0251c38c FT	458	* just the shift register IRQ -- other VIA interrupt sources are disabled.
	459	* On m68k macs, the VIA IRQ sources are dispatched individually. Unless
	460	* we are polling, the shift register IRQ flag has already been cleared.
	461	*/
	462
	463	#ifdef CONFIG_MAC
	464	if (!arg)
	465	#endif
	466	{
	467	if ((in_8(&via[IFR]) & SR_INT) == 0) {
	468	spin_unlock(&cuda_lock);
	469	return IRQ_NONE;
	470	} else {
	471	out_8(&via[IFR], SR_INT);
	472	}
1da177e4 LT	473	}
	474
	475	status = (~in_8(&via[B]) & (TIP\|TREQ)) \| (in_8(&via[ACR]) & SR_OUT);
	476	/* printk("cuda_interrupt: state=%d status=%x\n", cuda_state, status); */
	477	switch (cuda_state) {
	478	case idle:
	479	/* CUDA has sent us the first byte of data - unsolicited */
	480	if (status != TREQ)
	481	printk("cuda: state=idle, status=%x\n", status);
	482	(void)in_8(&via[SR]);
	483	out_8(&via[B], in_8(&via[B]) & ~TIP);
	484	cuda_state = reading;
	485	reply_ptr = cuda_rbuf;
	486	reading_reply = 0;
	487	break;
	488
	489	case awaiting_reply:
	490	/* CUDA has sent us the first byte of data of a reply */
	491	if (status != TREQ)
	492	printk("cuda: state=awaiting_reply, status=%x\n", status);
	493	(void)in_8(&via[SR]);
	494	out_8(&via[B], in_8(&via[B]) & ~TIP);
	495	cuda_state = reading;
	496	reply_ptr = current_req->reply;
	497	reading_reply = 1;
	498	break;
	499
	500	case sent_first_byte:
	501	if (status == TREQ + TIP + SR_OUT) {
	502	/* collision */
	503	out_8(&via[ACR], in_8(&via[ACR]) & ~SR_OUT);
	504	(void)in_8(&via[SR]);
	505	out_8(&via[B], in_8(&via[B]) \| TIP \| TACK);
	506	cuda_state = idle;
	507	} else {
	508	/* assert status == TIP + SR_OUT */
	509	if (status != TIP + SR_OUT)
	510	printk("cuda: state=sent_first_byte status=%x\n", status);
	511	out_8(&via[SR], current_req->data[1]);
	512	out_8(&via[B], in_8(&via[B]) ^ TACK);
	513	data_index = 2;
	514	cuda_state = sending;
	515	}
	516	break;
	517
	518	case sending:
	519	req = current_req;
	520	if (data_index >= req->nbytes) {
	521	out_8(&via[ACR], in_8(&via[ACR]) & ~SR_OUT);
	522	(void)in_8(&via[SR]);
	523	out_8(&via[B], in_8(&via[B]) \| TACK \| TIP);
	524	req->sent = 1;
	525	if (req->reply_expected) {
	526	cuda_state = awaiting_reply;
	527	} else {
	528	current_req = req->next;
	529	complete = 1;
	530	/* not sure about this */
	531	cuda_state = idle;
	532	cuda_start();
	533	}
	534	} else {
	535	out_8(&via[SR], req->data[data_index++]);
	536	out_8(&via[B], in_8(&via[B]) ^ TACK);
537	}
538	break;
539
540	case reading:
541	*reply_ptr++ = in_8(&via[SR]);
542	if (status == TIP) {
543	/* that's all folks */
544	out_8(&via[B], in_8(&via[B]) \| TACK \| TIP);
545	cuda_state = read_done;
546	} else {
547	/* assert status == TIP \| TREQ */
548	if (status != TIP + TREQ)
549	printk("cuda: state=reading status=%x\n", status);
550	out_8(&via[B], in_8(&via[B]) ^ TACK);
551	}
552	break;
553
554	case read_done:
555	(void)in_8(&via[SR]);
556	if (reading_reply) {
557	req = current_req;
558	req->reply_len = reply_ptr - req->reply;
559	if (req->data[0] == ADB_PACKET) {
560	/* Have to adjust the reply from ADB commands */
561	if (req->reply_len <= 2 \|\| (req->reply[1] & 2) != 0) {
562	/* the 0x2 bit indicates no response */
563	req->reply_len = 0;
564	} else {
565	/* leave just the command and result bytes in the reply */
566	req->reply_len -= 2;
567	memmove(req->reply, req->reply + 2, req->reply_len);
568	}
569	}
570	current_req = req->next;
571	complete = 1;
572	} else {
573	/* This is tricky. We must break the spinlock to call
574	* cuda_input. However, doing so means we might get
575	* re-entered from another CPU getting an interrupt
576	* or calling cuda_poll(). I ended up using the stack
577	* (it's only for 16 bytes) and moving the actual
578	* call to cuda_input to outside of the lock.
579	*/
580	ibuf_len = reply_ptr - cuda_rbuf;
581	memcpy(ibuf, cuda_rbuf, ibuf_len);
582	}
583	if (status == TREQ) {
584	out_8(&via[B], in_8(&via[B]) & ~TIP);
585	cuda_state = reading;
586	reply_ptr = cuda_rbuf;
587	reading_reply = 0;
588	} else {
589	cuda_state = idle;
590	cuda_start();
591	}
592	break;
593
594	default:
595	printk("cuda_interrupt: unknown cuda_state %d?\n", cuda_state);
596	}
597	spin_unlock(&cuda_lock);
598	if (complete && req) {
599	void (done)(struct adb_request ) = req->done;
600	mb();
601	req->complete = 1;
602	/* Here, we assume that if the request has a done member, the
603	* struct request will survive to setting req->complete to 1
604	*/
605	if (done)
606	(*done)(req);
607	}
608	if (ibuf_len)
7d12e780	609	cuda_input(ibuf, ibuf_len);
1da177e4 LT	610	return IRQ_HANDLED;
	611	}
	612
	613	static void
7d12e780	614	cuda_input(unsigned char *buf, int nb)
1da177e4 LT	615	{
	616	int i;
	617
	618	switch (buf[0]) {
	619	case ADB_PACKET:
	620	#ifdef CONFIG_XMON
	621	if (nb == 5 && buf[2] == 0x2c) {
	622	extern int xmon_wants_key, xmon_adb_keycode;
	623	if (xmon_wants_key) {
	624	xmon_adb_keycode = buf[3];
	625	return;
	626	}
	627	}
	628	#endif /* CONFIG_XMON */
	629	#ifdef CONFIG_ADB
7d12e780	630	adb_input(buf+2, nb-2, buf[1] & 0x40);
1da177e4 LT	631	#endif /* CONFIG_ADB */
	632	break;
	633
	634	default:
	635	printk("data from cuda (%d bytes):", nb);
	636	for (i = 0; i < nb; ++i)
	637	printk(" %.2x", buf[i]);
	638	printk("\n");
	639	}
	640	}