[linux.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/machw.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_init(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 = {
	"CUDA",
	cuda_probe,
	cuda_init,
	cuda_send_request,
	cuda_adb_autopoll,
	cuda_poll,
	cuda_reset_adb_bus
};
#endif /* CONFIG_ADB */

#ifdef CONFIG_PPC
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 /* CONFIG_PPC */

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

#ifdef CONFIG_MAC
    cuda_irq = IRQ_MAC_ADB;
#else /* CONFIG_MAC */
    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 /* CONFIG_MAC */

    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;
    via = via1;
#endif
    return 0;
}

static int __init
cuda_init(void)
{
#ifdef CONFIG_PPC
    if (via == NULL)
	return -ENODEV;
    return 0;
#else 
    int err = cuda_init_via();
    if (err) {
	printk(KERN_ERR "cuda_init_via() failed\n");
	return -ENODEV;
    }
    out_8(&via[IER], IER_SET|SR_INT); /* enable interrupt from SR */

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