via-pmu.c

linux 内核源代码

/* Construct and send a pmu request */
int
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);
	req->reply_len = 0;
	req->reply_expected = 0;
	return pmu_queue_request(req);
}

int
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 = NULL;
	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 inline void
wait_for_ack(void)
{
	/* Sightly increased the delay, I had one occurrence 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 inline void
send_byte(int x)
{
	volatile unsigned char __iomem *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 inline void
recv_byte(void)
{
	volatile unsigned char __iomem *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 inline void
pmu_done(struct adb_request *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);
}

static void
pmu_start(void)
{
	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
pmu_poll(void)
{
	if (!via)
		return;
	if (disable_poll)
		return;
	via_pmu_interrupt(0, NULL);
}

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

void
pmu_wait_complete(struct adb_request *req)
{
	if (!via)
		return;
	while((pmu_state != idle && pmu_state != locked) || !req->complete)
		via_pmu_interrupt(0, NULL);
}

/* 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
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_irqrestore(&pmu_lock, flags);
		if (req_awaiting_reply)
			adb_int_pending = 1;
		via_pmu_interrupt(0, NULL);
		spin_lock_irqsave(&pmu_lock, flags);
		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_nosync(gpio_irq);
			out_8(&via[IER], CB1_INT | IER_CLR);
			spin_unlock_irqrestore(&pmu_lock, flags);
#endif /* SUSPEND_USES_PMU */
			break;
		}
	} while (1);
}

void
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, pmu_intr_mask);
	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 */
}

/* Interrupt data could be the result data from an ADB cmd */
static void
pmu_handle_data(unsigned char *data, int len)
{
	unsigned char ints, pirq;
	int i = 0;

	asleep = 0;
	if (drop_interrupts || len < 1) {
		adb_int_pending = 0;
		pmu_irq_stats[8]++;
		return;
	}

	/* Get PMU interrupt mask */
	ints = data[0];

	/* Record zero interrupts for stats */
	if (ints == 0)
		pmu_irq_stats[9]++;

	/* Hack to deal with ADB autopoll flag */
	if (ints & PMU_INT_ADB)
		ints &= ~(PMU_INT_ADB_AUTO | PMU_INT_AUTO_SRQ_POLL);

next:

	if (ints == 0) {
		if (i > pmu_irq_stats[10])
			pmu_irq_stats[10] = i;
		return;
	}

	for (pirq = 0; pirq < 8; pirq++)
		if (ints & (1 << pirq))
			break;
	pmu_irq_stats[pirq]++;
	i++;
	ints &= ~(1 << pirq);

	/* Note: for some reason, we get an interrupt with len=1,
	 * data[0]==0 after each normal ADB interrupt, at least
	 * on the Pismo. Still investigating...  --BenH
	 */
	if ((1 << pirq) & 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 = NULL;
			if (len <= 2)
				req->reply_len = 0;
			else {
				memcpy(req->reply, data + 1, len - 1);
				req->reply_len = len - 1;
			}
			pmu_done(req);
		} else {
			if (len == 4 && data[1] == 0x2c) {
				extern int xmon_wants_key, xmon_adb_keycode;
				if (xmon_wants_key) {
					xmon_adb_keycode = data[2];
					return;
				}
			}
#ifdef CONFIG_ADB
			/*
			 * XXX On the [23]400 the PMU gives us an up
			 * event for keycodes 0x74 or 0x75 when the PC
			 * card eject buttons are released, so we
			 * ignore those events.
			 */
			if (!(pmu_kind == PMU_OHARE_BASED && len == 4
			      && data[1] == 0x2c && data[3] == 0xff
			      && (data[2] & ~1) == 0xf4))
				adb_input(data+1, len-1, 1);
#endif /* CONFIG_ADB */		
		}
	}
	/* Sound/brightness button pressed */
	else if ((1 << pirq) & PMU_INT_SNDBRT) {
#ifdef CONFIG_PMAC_BACKLIGHT
		if (len == 3)
			pmac_backlight_set_legacy_brightness_pmu(data[1] >> 4);
#endif
	}
	/* Tick interrupt */
	else if ((1 << pirq) & PMU_INT_TICK) {
		/* Environement or tick interrupt, query batteries */
		if (pmu_battery_count) {
			if ((--query_batt_timer) == 0) {
				query_battery_state();
				query_batt_timer = BATTERY_POLLING_COUNT;
			}
		}
        }
	else if ((1 << pirq) & PMU_INT_ENVIRONMENT) {
		if (pmu_battery_count)
			query_battery_state();
		pmu_pass_intr(data, len);
		/* len == 6 is probably a bad check. But how do I
		 * know what PMU versions send what events here? */
		if (len == 6) {
			via_pmu_event(PMU_EVT_POWER, !!(data[1]&8));
			via_pmu_event(PMU_EVT_LID, data[1]&1);
		}
	} else {
	       pmu_pass_intr(data, len);
	}
	goto next;
}

static struct adb_request*
pmu_sr_intr(void)
{
	struct adb_request *req;
	int bite = 0;

	if (via[B] & TREQ) {
		printk(KERN_ERR "PMU: spurious SR intr (%x)\n", via[B]);
		out_8(&via[IFR], SR_INT);
		return NULL;
	}
	/* The ack may not yet be low when we get the interrupt */
	while ((in_8(&via[B]) & TACK) != 0)
			;

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

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

	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
				return req;
		} 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[int_data_last];
		recv_byte();
		if (gpio_irq >= 0 && !gpio_irq_enabled) {
			enable_irq(gpio_irq);
			gpio_irq_enabled = 1;
		}
		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 if (data_index < 32) {
			reply_ptr[data_index++] = bite;
		}
		if (data_index < data_len) {
			recv_byte();
			break;
		}

		if (pmu_state == reading_intr) {
			pmu_state = idle;
			int_data_state[int_data_last] = int_data_ready;
			interrupt_data_len[int_data_last] = data_len;
		} else {
			req = current_req;
			/* 
			 * For PMU sleep and freq change requests, we lock the
			 * PMU until it's explicitly unlocked. This avoids any
			 * spurrious event polling getting in
			 */
			current_req = req->next;
			req->reply_len += data_index;
			if (req->data[0] == PMU_SLEEP || req->data[0] == PMU_CPU_SPEED)
				pmu_state = locked;
			else
				pmu_state = idle;
			return req;
		}
		break;

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

static irqreturn_t
via_pmu_interrupt(int irq, void *arg)
{
	unsigned long flags;
	int intr;
	int nloop = 0;
	int int_data = -1;
	struct adb_request *req = NULL;
	int handled = 0;

	/* This is a bit brutal, we can probably do better */
	spin_lock_irqsave(&pmu_lock, flags);
	++disable_poll;
	
	for (;;) {
		intr = in_8(&via[IFR]) & (SR_INT | CB1_INT);
		if (intr == 0)
			break;
		handled = 1;
		if (++nloop > 1000) {
			printk(KERN_DEBUG "PMU: stuck in intr loop, "
			       "intr=%x, ier=%x pmu_state=%d\n",
			       intr, in_8(&via[IER]), pmu_state);
			break;
		}
		out_8(&via[IFR], intr);
		if (intr & CB1_INT) {
			adb_int_pending = 1;
			pmu_irq_stats[0]++;
		}
		if (intr & SR_INT) {
			req = pmu_sr_intr();
			if (req)
				break;
		}
	}

recheck:
	if (pmu_state == idle) {
		if (adb_int_pending) {
			if (int_data_state[0] == int_data_empty)
				int_data_last = 0;
			else if (int_data_state[1] == int_data_empty)
				int_data_last = 1;
			else
				goto no_free_slot;
			pmu_state = intack;
			int_data_state[int_data_last] = int_data_fill;
			/* 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();
	}
no_free_slot:			
	/* Mark the oldest buffer for flushing */
	if (int_data_state[!int_data_last] == int_data_ready) {
		int_data_state[!int_data_last] = int_data_flush;
		int_data = !int_data_last;
	} else if (int_data_state[int_data_last] == int_data_ready) {
		int_data_state[int_data_last] = int_data_flush;
		int_data = int_data_last;