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