ap_bus.c

linux 内核源代码

	}
	return 0;
}

/**
 * uevent function for AP devices. It sets up a single environment
 * variable DEV_TYPE which contains the hardware device type.
 */
static int ap_uevent (struct device *dev, struct kobj_uevent_env *env)
{
	struct ap_device *ap_dev = to_ap_dev(dev);
	int retval = 0;

	if (!ap_dev)
		return -ENODEV;

	/* Set up DEV_TYPE environment variable. */
	retval = add_uevent_var(env, "DEV_TYPE=%04X", ap_dev->device_type);
	if (retval)
		return retval;

	/* Add MODALIAS= */
	retval = add_uevent_var(env, "MODALIAS=ap:t%02X", ap_dev->device_type);

	return retval;
}

static struct bus_type ap_bus_type = {
	.name = "ap",
	.match = &ap_bus_match,
	.uevent = &ap_uevent,
};

static int ap_device_probe(struct device *dev)
{
	struct ap_device *ap_dev = to_ap_dev(dev);
	struct ap_driver *ap_drv = to_ap_drv(dev->driver);
	int rc;

	ap_dev->drv = ap_drv;
	spin_lock_bh(&ap_device_lock);
	list_add(&ap_dev->list, &ap_device_list);
	spin_unlock_bh(&ap_device_lock);
	rc = ap_drv->probe ? ap_drv->probe(ap_dev) : -ENODEV;
	return rc;
}

/**
 * Flush all requests from the request/pending queue of an AP device.
 * @ap_dev: pointer to the AP device.
 */
static void __ap_flush_queue(struct ap_device *ap_dev)
{
	struct ap_message *ap_msg, *next;

	list_for_each_entry_safe(ap_msg, next, &ap_dev->pendingq, list) {
		list_del_init(&ap_msg->list);
		ap_dev->pendingq_count--;
		ap_dev->drv->receive(ap_dev, ap_msg, ERR_PTR(-ENODEV));
	}
	list_for_each_entry_safe(ap_msg, next, &ap_dev->requestq, list) {
		list_del_init(&ap_msg->list);
		ap_dev->requestq_count--;
		ap_dev->drv->receive(ap_dev, ap_msg, ERR_PTR(-ENODEV));
	}
}

void ap_flush_queue(struct ap_device *ap_dev)
{
	spin_lock_bh(&ap_dev->lock);
	__ap_flush_queue(ap_dev);
	spin_unlock_bh(&ap_dev->lock);
}
EXPORT_SYMBOL(ap_flush_queue);

static int ap_device_remove(struct device *dev)
{
	struct ap_device *ap_dev = to_ap_dev(dev);
	struct ap_driver *ap_drv = ap_dev->drv;

	ap_flush_queue(ap_dev);
	del_timer_sync(&ap_dev->timeout);
	if (ap_drv->remove)
		ap_drv->remove(ap_dev);
	spin_lock_bh(&ap_device_lock);
	list_del_init(&ap_dev->list);
	spin_unlock_bh(&ap_device_lock);
	spin_lock_bh(&ap_dev->lock);
	atomic_sub(ap_dev->queue_count, &ap_poll_requests);
	spin_unlock_bh(&ap_dev->lock);
	return 0;
}

int ap_driver_register(struct ap_driver *ap_drv, struct module *owner,
		       char *name)
{
	struct device_driver *drv = &ap_drv->driver;

	drv->bus = &ap_bus_type;
	drv->probe = ap_device_probe;
	drv->remove = ap_device_remove;
	drv->owner = owner;
	drv->name = name;
	return driver_register(drv);
}
EXPORT_SYMBOL(ap_driver_register);

void ap_driver_unregister(struct ap_driver *ap_drv)
{
	driver_unregister(&ap_drv->driver);
}
EXPORT_SYMBOL(ap_driver_unregister);

/**
 * AP bus attributes.
 */
static ssize_t ap_domain_show(struct bus_type *bus, char *buf)
{
	return snprintf(buf, PAGE_SIZE, "%d\n", ap_domain_index);
}

static BUS_ATTR(ap_domain, 0444, ap_domain_show, NULL);

static ssize_t ap_config_time_show(struct bus_type *bus, char *buf)
{
	return snprintf(buf, PAGE_SIZE, "%d\n", ap_config_time);
}

static ssize_t ap_config_time_store(struct bus_type *bus,
				    const char *buf, size_t count)
{
	int time;

	if (sscanf(buf, "%d\n", &time) != 1 || time < 5 || time > 120)
		return -EINVAL;
	ap_config_time = time;
	if (!timer_pending(&ap_config_timer) ||
	    !mod_timer(&ap_config_timer, jiffies + ap_config_time * HZ)) {
		ap_config_timer.expires = jiffies + ap_config_time * HZ;
		add_timer(&ap_config_timer);
	}
	return count;
}

static BUS_ATTR(config_time, 0644, ap_config_time_show, ap_config_time_store);

static ssize_t ap_poll_thread_show(struct bus_type *bus, char *buf)
{
	return snprintf(buf, PAGE_SIZE, "%d\n", ap_poll_kthread ? 1 : 0);
}

static ssize_t ap_poll_thread_store(struct bus_type *bus,
				    const char *buf, size_t count)
{
	int flag, rc;

	if (sscanf(buf, "%d\n", &flag) != 1)
		return -EINVAL;
	if (flag) {
		rc = ap_poll_thread_start();
		if (rc)
			return rc;
	}
	else
		ap_poll_thread_stop();
	return count;
}

static BUS_ATTR(poll_thread, 0644, ap_poll_thread_show, ap_poll_thread_store);

static struct bus_attribute *const ap_bus_attrs[] = {
	&bus_attr_ap_domain,
	&bus_attr_config_time,
	&bus_attr_poll_thread,
	NULL
};

/**
 * Pick one of the 16 ap domains.
 */
static int ap_select_domain(void)
{
	int queue_depth, device_type, count, max_count, best_domain;
	int rc, i, j;

	/**
	 * We want to use a single domain. Either the one specified with
	 * the "domain=" parameter or the domain with the maximum number
	 * of devices.
	 */
	if (ap_domain_index >= 0 && ap_domain_index < AP_DOMAINS)
		/* Domain has already been selected. */
		return 0;
	best_domain = -1;
	max_count = 0;
	for (i = 0; i < AP_DOMAINS; i++) {
		count = 0;
		for (j = 0; j < AP_DEVICES; j++) {
			ap_qid_t qid = AP_MKQID(j, i);
			rc = ap_query_queue(qid, &queue_depth, &device_type);
			if (rc)
				continue;
			count++;
		}
		if (count > max_count) {
			max_count = count;
			best_domain = i;
		}
	}
	if (best_domain >= 0){
		ap_domain_index = best_domain;
		return 0;
	}
	return -ENODEV;
}

/**
 * Find the device type if query queue returned a device type of 0.
 * @ap_dev: pointer to the AP device.
 */
static int ap_probe_device_type(struct ap_device *ap_dev)
{
	static unsigned char msg[] = {
		0x00,0x06,0x00,0x00,0x00,0x00,0x00,0x00,
		0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
		0x00,0x00,0x00,0x58,0x00,0x00,0x00,0x00,
		0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
		0x01,0x00,0x43,0x43,0x41,0x2d,0x41,0x50,
		0x50,0x4c,0x20,0x20,0x20,0x01,0x01,0x01,
		0x00,0x00,0x00,0x00,0x50,0x4b,0x00,0x00,
		0x00,0x00,0x01,0x1c,0x00,0x00,0x00,0x00,
		0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
		0x00,0x00,0x05,0xb8,0x00,0x00,0x00,0x00,
		0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
		0x70,0x00,0x41,0x00,0x00,0x00,0x00,0x00,
		0x00,0x00,0x54,0x32,0x01,0x00,0xa0,0x00,
		0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
		0x00,0x00,0x00,0x00,0xb8,0x05,0x00,0x00,
		0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
		0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
		0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
		0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
		0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
		0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
		0x00,0x00,0x0a,0x00,0x00,0x00,0x00,0x00,
		0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
		0x00,0x00,0x00,0x00,0x00,0x00,0x08,0x00,
		0x49,0x43,0x53,0x46,0x20,0x20,0x20,0x20,
		0x50,0x4b,0x0a,0x00,0x50,0x4b,0x43,0x53,
		0x2d,0x31,0x2e,0x32,0x37,0x00,0x11,0x22,
		0x33,0x44,0x55,0x66,0x77,0x88,0x99,0x00,
		0x11,0x22,0x33,0x44,0x55,0x66,0x77,0x88,
		0x99,0x00,0x11,0x22,0x33,0x44,0x55,0x66,
		0x77,0x88,0x99,0x00,0x11,0x22,0x33,0x44,
		0x55,0x66,0x77,0x88,0x99,0x00,0x11,0x22,
		0x33,0x44,0x55,0x66,0x77,0x88,0x99,0x00,
		0x11,0x22,0x33,0x5d,0x00,0x5b,0x00,0x77,
		0x88,0x1e,0x00,0x00,0x57,0x00,0x00,0x00,
		0x00,0x04,0x00,0x00,0x4f,0x00,0x00,0x00,
		0x03,0x02,0x00,0x00,0x40,0x01,0x00,0x01,
		0xce,0x02,0x68,0x2d,0x5f,0xa9,0xde,0x0c,
		0xf6,0xd2,0x7b,0x58,0x4b,0xf9,0x28,0x68,
		0x3d,0xb4,0xf4,0xef,0x78,0xd5,0xbe,0x66,
		0x63,0x42,0xef,0xf8,0xfd,0xa4,0xf8,0xb0,
		0x8e,0x29,0xc2,0xc9,0x2e,0xd8,0x45,0xb8,
		0x53,0x8c,0x6f,0x4e,0x72,0x8f,0x6c,0x04,
		0x9c,0x88,0xfc,0x1e,0xc5,0x83,0x55,0x57,
		0xf7,0xdd,0xfd,0x4f,0x11,0x36,0x95,0x5d,
	};
	struct ap_queue_status status;
	unsigned long long psmid;
	char *reply;
	int rc, i;

	reply = (void *) get_zeroed_page(GFP_KERNEL);
	if (!reply) {
		rc = -ENOMEM;
		goto out;
	}

	status = __ap_send(ap_dev->qid, 0x0102030405060708ULL,
			   msg, sizeof(msg));
	if (status.response_code != AP_RESPONSE_NORMAL) {
		rc = -ENODEV;
		goto out_free;
	}

	/* Wait for the test message to complete. */
	for (i = 0; i < 6; i++) {
		mdelay(300);
		status = __ap_recv(ap_dev->qid, &psmid, reply, 4096);
		if (status.response_code == AP_RESPONSE_NORMAL &&
		    psmid == 0x0102030405060708ULL)
			break;
	}
	if (i < 6) {
		/* Got an answer. */
		if (reply[0] == 0x00 && reply[1] == 0x86)
			ap_dev->device_type = AP_DEVICE_TYPE_PCICC;
		else
			ap_dev->device_type = AP_DEVICE_TYPE_PCICA;
		rc = 0;
	} else
		rc = -ENODEV;

out_free:
	free_page((unsigned long) reply);
out:
	return rc;
}

/**
 * Scan the ap bus for new devices.
 */
static int __ap_scan_bus(struct device *dev, void *data)
{
	return to_ap_dev(dev)->qid == (ap_qid_t)(unsigned long) data;
}

static void ap_device_release(struct device *dev)
{
	struct ap_device *ap_dev = to_ap_dev(dev);

	kfree(ap_dev);
}

static void ap_scan_bus(struct work_struct *unused)
{
	struct ap_device *ap_dev;
	struct device *dev;
	ap_qid_t qid;
	int queue_depth, device_type;
	int rc, i;

	if (ap_select_domain() != 0)
		return;
	for (i = 0; i < AP_DEVICES; i++) {
		qid = AP_MKQID(i, ap_domain_index);
		dev = bus_find_device(&ap_bus_type, NULL,
				      (void *)(unsigned long)qid,
				      __ap_scan_bus);
		rc = ap_query_queue(qid, &queue_depth, &device_type);
		if (dev) {
			if (rc == -EBUSY) {
				set_current_state(TASK_UNINTERRUPTIBLE);
				schedule_timeout(AP_RESET_TIMEOUT);
				rc = ap_query_queue(qid, &queue_depth,
						    &device_type);
			}
			ap_dev = to_ap_dev(dev);
			spin_lock_bh(&ap_dev->lock);
			if (rc || ap_dev->unregistered) {
				spin_unlock_bh(&ap_dev->lock);
				device_unregister(dev);
				put_device(dev);
				continue;
			}
			spin_unlock_bh(&ap_dev->lock);
			put_device(dev);
			continue;
		}
		if (rc)
			continue;
		rc = ap_init_queue(qid);
		if (rc)
			continue;
		ap_dev = kzalloc(sizeof(*ap_dev), GFP_KERNEL);
		if (!ap_dev)
			break;
		ap_dev->qid = qid;
		ap_dev->queue_depth = queue_depth;
		ap_dev->unregistered = 1;
		spin_lock_init(&ap_dev->lock);
		INIT_LIST_HEAD(&ap_dev->pendingq);
		INIT_LIST_HEAD(&ap_dev->requestq);
		INIT_LIST_HEAD(&ap_dev->list);
		setup_timer(&ap_dev->timeout, ap_request_timeout,
			    (unsigned long) ap_dev);
		if (device_type == 0)
			ap_probe_device_type(ap_dev);
		else
			ap_dev->device_type = device_type;

		ap_dev->device.bus = &ap_bus_type;
		ap_dev->device.parent = ap_root_device;
		snprintf(ap_dev->device.bus_id, BUS_ID_SIZE, "card%02x",
			 AP_QID_DEVICE(ap_dev->qid));
		ap_dev->device.release = ap_device_release;
		rc = device_register(&ap_dev->device);
		if (rc) {
			kfree(ap_dev);
			continue;
		}
		/* Add device attributes. */
		rc = sysfs_create_group(&ap_dev->device.kobj,
					&ap_dev_attr_group);
		if (!rc) {
			spin_lock_bh(&ap_dev->lock);
			ap_dev->unregistered = 0;
			spin_unlock_bh(&ap_dev->lock);
		}
		else
			device_unregister(&ap_dev->device);
	}
}

static void
ap_config_timeout(unsigned long ptr)
{
	queue_work(ap_work_queue, &ap_config_work);
	ap_config_timer.expires = jiffies + ap_config_time * HZ;
	add_timer(&ap_config_timer);
}

/**
 * Set up the timer to run the poll tasklet
 */
static inline void ap_schedule_poll_timer(void)
{
	if (timer_pending(&ap_poll_timer))
		return;
	mod_timer(&ap_poll_timer, jiffies + AP_POLL_TIME);
}

/**
 * Receive pending reply messages from an AP device.
 * @ap_dev: pointer to the AP device
 * @flags: pointer to control flags, bit 2^0 is set if another poll is
 *	   required, bit 2^1 is set if the poll timer needs to get armed
 * Returns 0 if the device is still present, -ENODEV if not.
 */
static int ap_poll_read(struct ap_device *ap_dev, unsigned long *flags)
{
	struct ap_queue_status status;
	struct ap_message *ap_msg;

	if (ap_dev->queue_count <= 0)
		return 0;
	status = __ap_recv(ap_dev->qid, &ap_dev->reply->psmid,
			   ap_dev->reply->message, ap_dev->reply->length);
	switch (status.response_code) {
	case AP_RESPONSE_NORMAL:
		atomic_dec(&ap_poll_requests);
		ap_decrease_queue_count(ap_dev);
		list_for_each_entry(ap_msg, &ap_dev->pendingq, list) {
			if (ap_msg->psmid != ap_dev->reply->psmid)
				continue;
			list_del_init(&ap_msg->list);
			ap_dev->pendingq_count--;
			ap_dev->drv->receive(ap_dev, ap_msg, ap_dev->reply);
			break;
		}