[mirror_ubuntu-artful-kernel.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/sched.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);

#ifdef CONFIG_MAC
#define CUDA_IRQ IRQ_MAC_ADB
#define eieio()
#else
#define CUDA_IRQ vias->intrs[0].line
#endif

/* 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;
#ifdef CONFIG_PPC
static struct device_node *vias;
#endif
static int cuda_fully_inited = 0;

#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, struct pt_regs *regs);
static void cuda_input(unsigned char *buf, int nb, struct pt_regs *regs);
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;
    u32 *reg;
    int err;

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

    reg = (u32 *)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        */

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

    /* 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;

    if (request_irq(CUDA_IRQ, cuda_interrupt, 0, "ADB", cuda_interrupt)) {
	printk(KERN_ERR "cuda_init: can't get 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;
    }

    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 */
#ifndef CONFIG_MAC
    out_8(&via[IER], 0x7f);					/* disable interrupts from VIA */
    (void)in_8(&via[IER]);
#endif

    /* delay 4ms and then clear any pending interrupt */
    mdelay(4);
    (void)in_8(&via[SR]);
    out_8(&via[IFR], in_8(&via[IFR]) & 0x7f);

    /* 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], in_8(&via[IFR]) & 0x7f);

    /* 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], in_8(&via[IFR]) & 0x7f);
    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)
{
    unsigned long flags;

    /* cuda_interrupt only takes a normal lock, we disable
     * interrupts here to avoid re-entering and thus deadlocking.
     * An option would be to disable only the IRQ source with
     * disable_irq(), would that work on m68k ? --BenH
     */
    local_irq_save(flags);
    cuda_interrupt(0, NULL, NULL);
    local_irq_restore(flags);
}

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

    virq = in_8(&via[IFR]) & 0x7f;
    out_8(&via[IFR], virq);   
    if ((virq & SR_INT) == 0) {
        spin_unlock(&cuda_lock);
	return IRQ_NONE;
    }
    
    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, regs);
    return IRQ_HANDLED;
}

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