via-pmu.c

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		while (!req->complete)
			pmu_poll();

	return 0;
}

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

	if ((vias == NULL) || (!pmu_fully_inited) || !pmu_has_adb)
		return -ENXIO;

	if (devs) {
		adb_dev_map = devs;
		pmu_request(&req, NULL, 5, PMU_ADB_CMD, 0, 0x86,
			    adb_dev_map >> 8, adb_dev_map);
		pmu_adb_flags = 2;
	} else {
		pmu_request(&req, NULL, 1, PMU_ADB_POLL_OFF);
		pmu_adb_flags = 0;
	}
	while (!req.complete)
		pmu_poll();
	return 0;
}

/* Reset the ADB bus */
static int __openfirmware
pmu_adb_reset_bus(void)
{
	struct adb_request req;
	int save_autopoll = adb_dev_map;

	if ((vias == NULL) || (!pmu_fully_inited) || !pmu_has_adb)
		return -ENXIO;

	/* anyone got a better idea?? */
	pmu_adb_autopoll(0);

	req.nbytes = 5;
	req.done = NULL;
	req.data[0] = PMU_ADB_CMD;
	req.data[1] = 0;
	req.data[2] = ADB_BUSRESET; /* 3 ??? */
	req.data[3] = 0;
	req.data[4] = 0;
	req.reply_len = 0;
	req.reply_expected = 1;
	if (pmu_queue_request(&req) != 0) {
		printk(KERN_ERR "pmu_adb_reset_bus: pmu_queue_request failed\n");
		return -EIO;
	}
	while (!req.complete)
		pmu_poll();

	if (save_autopoll != 0)
		pmu_adb_autopoll(save_autopoll);

	return 0;
}
#endif /* CONFIG_ADB */

/* Construct and send a pmu request */
int __openfirmware
pmu_request(struct adb_request *req, void (*done)(struct adb_request *),
	    int nbytes, ...)
{
	va_list list;
	int i;

	if (vias == NULL)
		return -ENXIO;

	if (nbytes < 0 || nbytes > 32) {
		printk(KERN_ERR "pmu_request: bad nbytes (%d)\n", nbytes);
		req->complete = 1;
		return -EINVAL;
	}
	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);
	if (pmu_data_len[req->data[0]][1] != 0) {
		req->reply[0] = ADB_RET_OK;
		req->reply_len = 1;
	} else
		req->reply_len = 0;
	req->reply_expected = 0;
	return pmu_queue_request(req);
}

int __openfirmware
pmu_queue_request(struct adb_request *req)
{
	unsigned long flags;
	int nsend;

	if (via == NULL) {
		req->complete = 1;
		return -ENXIO;
	}
	if (req->nbytes <= 0) {
		req->complete = 1;
		return 0;
	}
	nsend = pmu_data_len[req->data[0]][0];
	if (nsend >= 0 && req->nbytes != nsend + 1) {
		req->complete = 1;
		return -EINVAL;
	}

	req->next = 0;
	req->sent = 0;
	req->complete = 0;

	spin_lock_irqsave(&pmu_lock, flags);
	if (current_req != 0) {
		last_req->next = req;
		last_req = req;
	} else {
		current_req = req;
		last_req = req;
		if (pmu_state == idle)
			pmu_start();
	}
	spin_unlock_irqrestore(&pmu_lock, flags);

	return 0;
}

static void __openfirmware
wait_for_ack(void)
{
	/* Sightly increased the delay, I had one occurence of the message
	 * reported
	 */
	int timeout = 4000;
	while ((in_8(&via[B]) & TACK) == 0) {
		if (--timeout < 0) {
			printk(KERN_ERR "PMU not responding (!ack)\n");
			return;
		}
		udelay(10);
	}
}

/* New PMU seems to be very sensitive to those timings, so we make sure
 * PCI is flushed immediately */
static void __openfirmware
send_byte(int x)
{
	volatile unsigned char *v = via;

	out_8(&v[ACR], in_8(&v[ACR]) | SR_OUT | SR_EXT);
	out_8(&v[SR], x);
	out_8(&v[B], in_8(&v[B]) & ~TREQ);		/* assert TREQ */
	(void)in_8(&v[B]);
}

static void __openfirmware
recv_byte()
{
	volatile unsigned char *v = via;

	out_8(&v[ACR], (in_8(&v[ACR]) & ~SR_OUT) | SR_EXT);
	in_8(&v[SR]);		/* resets SR */
	out_8(&v[B], in_8(&v[B]) & ~TREQ);
	(void)in_8(&v[B]);
}

static volatile int disable_poll;

static void __openfirmware
pmu_start()
{
	struct adb_request *req;

	/* assert pmu_state == idle */
	/* get the packet to send */
	req = current_req;
	if (req == 0 || pmu_state != idle
	    || (/*req->reply_expected && */req_awaiting_reply))
		return;

	pmu_state = sending;
	data_index = 1;
	data_len = pmu_data_len[req->data[0]][0];

	/* Sounds safer to make sure ACK is high before writing. This helped
	 * kill a problem with ADB and some iBooks
	 */
	wait_for_ack();
	/* set the shift register to shift out and send a byte */
	send_byte(req->data[0]);
}

void __openfirmware
pmu_poll()
{
	if (!via)
		return;
	if (disable_poll)
		return;
	/* Kicks ADB read when PMU is suspended */
	if (pmu_suspended)
		adb_int_pending = 1;
	do {
		via_pmu_interrupt(0, 0, 0);
	} while (pmu_suspended && (adb_int_pending || pmu_state != idle
		|| req_awaiting_reply));
}

/* This function loops until the PMU is idle and prevents it from
 * anwsering to ADB interrupts. pmu_request can still be called.
 * This is done to avoid spurrious shutdowns when we know we'll have
 * interrupts switched off for a long time
 */
void __openfirmware
pmu_suspend(void)
{
	unsigned long flags;
#ifdef SUSPEND_USES_PMU
	struct adb_request *req;
#endif
	if (!via)
		return;
	
	spin_lock_irqsave(&pmu_lock, flags);
	pmu_suspended++;
	if (pmu_suspended > 1) {
		spin_unlock_irqrestore(&pmu_lock, flags);
		return;
	}

	do {
		spin_unlock(&pmu_lock);
		via_pmu_interrupt(0, 0, 0);
		spin_lock(&pmu_lock);
		if (!adb_int_pending && pmu_state == idle && !req_awaiting_reply) {
#ifdef SUSPEND_USES_PMU
			pmu_request(&req, NULL, 2, PMU_SET_INTR_MASK, 0);
			spin_unlock_irqrestore(&pmu_lock, flags);
			while(!req.complete)
				pmu_poll();
#else /* SUSPEND_USES_PMU */
			if (gpio_irq >= 0)
				disable_irq(gpio_irq);
			out_8(&via[IER], CB1_INT | IER_CLR);
			spin_unlock_irqrestore(&pmu_lock, flags);
#endif /* SUSPEND_USES_PMU */
			break;
		}
	} while (1);
}

void __openfirmware
pmu_resume(void)
{
	unsigned long flags;

	if (!via || (pmu_suspended < 1))
		return;

	spin_lock_irqsave(&pmu_lock, flags);
	pmu_suspended--;
	if (pmu_suspended > 0) {
		spin_unlock_irqrestore(&pmu_lock, flags);
		return;
	}
	adb_int_pending = 1;
#ifdef SUSPEND_USES_PMU
	pmu_request(&req, NULL, 2, PMU_SET_INTR_MASK, 0xfc);
	spin_unlock_irqrestore(&pmu_lock, flags);
	while(!req.complete)
		pmu_poll();
#else /* SUSPEND_USES_PMU */
	if (gpio_irq >= 0)
		enable_irq(gpio_irq);
	out_8(&via[IER], CB1_INT | IER_SET);
	spin_unlock_irqrestore(&pmu_lock, flags);
	pmu_poll();
#endif /* SUSPEND_USES_PMU */
}

static void __openfirmware
via_pmu_interrupt(int irq, void *arg, struct pt_regs *regs)
{
	unsigned long flags;
	int intr;
	int nloop = 0;

	/* This is a bit brutal, we can probably do better */
	spin_lock_irqsave(&pmu_lock, flags);
	++disable_poll;
		
	while ((intr = in_8(&via[IFR])) != 0) {
		if (++nloop > 1000) {
			printk(KERN_DEBUG "PMU: stuck in intr loop, "
			       "intr=%x pmu_state=%d\n", intr, pmu_state);
			break;
		}
		if (intr & SR_INT)
			pmu_sr_intr(regs);
		else if (intr & CB1_INT) {
			adb_int_pending = 1;
			out_8(&via[IFR], CB1_INT);
		}
		intr &= ~(SR_INT | CB1_INT);
		if (intr != 0) {
			out_8(&via[IFR], intr);
		}
	}
	/* This is not necessary except if synchronous ADB requests are done
	 * with interrupts off, which should not happen. Since I'm not sure
	 * this "wiring" will remain, I'm commenting it out for now. Please do
	 * not remove. -- BenH.
	 */
#if 0
	if (gpio_reg && !pmu_suspended && (in_8(gpio_reg + 0x9) & 0x02) == 0)
		adb_int_pending = 1;
#endif

	if (pmu_state == idle) {
		if (adb_int_pending) {
			pmu_state = intack;
			/* Sounds safer to make sure ACK is high before writing.
			 * This helped kill a problem with ADB and some iBooks
			 */
			wait_for_ack();
			send_byte(PMU_INT_ACK);
			adb_int_pending = 0;
		} else if (current_req) {
			pmu_start();
		}
	}
	
	--disable_poll;
	spin_unlock_irqrestore(&pmu_lock, flags);
}

static void __openfirmware
gpio1_interrupt(int irq, void *arg, struct pt_regs *regs)
{
	adb_int_pending = 1;
	via_pmu_interrupt(0, 0, 0);
}

static void __openfirmware
pmu_sr_intr(struct pt_regs *regs)
{
	struct adb_request *req;
	int bite;

	if (via[B] & TREQ) {
		printk(KERN_ERR "PMU: spurious SR intr (%x)\n", via[B]);
		out_8(&via[IFR], SR_INT);
		return;
	}
	/* This one seems to appear with PMU99. According to OF methods,
	 * the protocol didn't change...
	 */
	if (via[B] & TACK) {
		while ((in_8(&via[B]) & TACK) != 0)
			;
	}

	/* reset TREQ and wait for TACK to go high */
	out_8(&via[B], in_8(&via[B]) | TREQ);
	wait_for_ack();

	/* if reading grab the byte, and reset the interrupt */
	if (pmu_state == reading || pmu_state == reading_intr)
		bite = in_8(&via[SR]);

	out_8(&via[IFR], SR_INT);

	switch (pmu_state) {
	case sending:
		req = current_req;
		if (data_len < 0) {
			data_len = req->nbytes - 1;
			send_byte(data_len);
			break;
		}
		if (data_index <= data_len) {
			send_byte(req->data[data_index++]);
			break;
		}
		req->sent = 1;
		data_len = pmu_data_len[req->data[0]][1];
		if (data_len == 0) {
			pmu_state = idle;
			current_req = req->next;
			if (req->reply_expected)
				req_awaiting_reply = req;
			else {
				spin_unlock(&pmu_lock);
				pmu_done(req);
				spin_lock(&pmu_lock);
			}
		} else {
			pmu_state = reading;
			data_index = 0;
			reply_ptr = req->reply + req->reply_len;
			recv_byte();
		}
		break;

	case intack:
		data_index = 0;
		data_len = -1;
		pmu_state = reading_intr;
		reply_ptr = interrupt_data;
		recv_byte();
		break;

	case reading:
	case reading_intr:
		if (data_len == -1) {
			data_len = bite;
			if (bite > 32)
				printk(KERN_ERR "PMU: bad reply len %d\n",
				       bite);
		} else {
			reply_ptr[data_index++] = bite;
		}
		if (data_index < data_len) {
			recv_byte();
			break;
		}

		if (pmu_state == reading_intr) {
			spin_unlock(&pmu_lock);
			pmu_handle_data(interrupt_data, data_index, regs);
			spin_lock(&pmu_lock);
		} else {
			req = current_req;
			current_req = req->next;
			req->reply_len += data_index;
			spin_unlock(&pmu_lock);
			pmu_done(req);
			spin_lock(&pmu_lock);
		}
		pmu_state = idle;

		break;

	default:
		printk(KERN_ERR "via_pmu_interrupt: unknown state %d?\n",
		       pmu_state);
	}
}

static void __openfirmware
pmu_done(struct adb_request *req)
{
	req->complete = 1;
	if (req->done)
		(*req->done)(req);
}

/* Interrupt data could be the result data from an ADB cmd */
static void __openfirmware
pmu_handle_data(unsigned char *data, int len, struct pt_regs *regs)
{
	asleep = 0;
	if (len < 1) {
//		xmon_printk("empty ADB\n");
		adb_int_pending = 0;
		return;
	}
	if (data[0] & PMU_INT_ADB) {
		if ((data[0] & PMU_INT_ADB_AUTO) == 0) {
			struct adb_request *req = req_awaiting_reply;
			if (req == 0) {
				printk(KERN_ERR "PMU: extra ADB reply\n");
				return;
			}
			req_awaiting_reply = 0;
			if (len <= 2)
				req->reply_len = 0;
			else {
				memcpy(req->reply, data + 1, len - 1);
				req->reply_len = len - 1;
			}
			pmu_done(req);