sgi_hotplug.c

audio driver for hotplug pci on linux 2.6.27

			       __func__, ret);
			/* try to continue on */
		}
	}

	num_funcs = pci_scan_slot(slot->pci_bus,
				  PCI_DEVFN(slot->device_num + 1, 0));
	if (!num_funcs) {
		dev_dbg(&slot->pci_bus->self->dev, "no device in slot\n");
		mutex_unlock(&sn_hotplug_mutex);
		return -ENODEV;
	}

	/*
	 * Map SN resources for all functions on the card
	 * to the Linux PCI interface and tell the drivers
	 * about them.
	 */
	for (func = 0; func < num_funcs;  func++) {
		dev = pci_get_slot(slot->pci_bus,
				   PCI_DEVFN(slot->device_num + 1,
					     PCI_FUNC(func)));
		if (dev) {
			/* Need to do slot fixup on PPB before fixup of children
			 * (PPB's pcidev_info needs to be in pcidev_info list
			 * before child's SN_PCIDEV_INFO() call to setup
			 * pdi_host_pcidev_info).
			 */
			pcibios_fixup_device_resources(dev);
			if (SN_ACPI_BASE_SUPPORT())
				sn_acpi_slot_fixup(dev);
			else
				sn_io_slot_fixup(dev);
			if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
				unsigned char sec_bus;
				pci_read_config_byte(dev, PCI_SECONDARY_BUS,
						     &sec_bus);
				new_bus = pci_add_new_bus(dev->bus, dev,
							  sec_bus);
				pci_scan_child_bus(new_bus);
				new_ppb = 1;
			}
			pci_dev_put(dev);
		}
	}

	/*
	 * Add the slot's devices to the ACPI infrastructure */
	if (SN_ACPI_BASE_SUPPORT() && ssdt) {
		unsigned long long adr;
		struct acpi_device *pdevice;
		struct acpi_device *device;
		acpi_handle phandle;
		acpi_handle chandle = NULL;
		acpi_handle rethandle;
		acpi_status ret;

		phandle = PCI_CONTROLLER(slot->pci_bus)->acpi_handle;

		if (acpi_bus_get_device(phandle, &pdevice)) {
			dev_dbg(&slot->pci_bus->self->dev,
				"no parent device, assuming NULL\n");
			pdevice = NULL;
		}

		/*
		 * Walk the rootbus node's immediate children looking for
		 * the slot's device node(s). There can be more than
		 * one for multifunction devices.
		 */
		for (;;) {
			rethandle = NULL;
			ret = acpi_get_next_object(ACPI_TYPE_DEVICE,
						   phandle, chandle,
						   &rethandle);

			if (ret == AE_NOT_FOUND || rethandle == NULL)
				break;

			chandle = rethandle;

			ret = acpi_evaluate_integer(chandle, METHOD_NAME__ADR,
						    NULL, &adr);

			if (ACPI_SUCCESS(ret) &&
			    (adr>>16) == (slot->device_num + 1)) {

				ret = acpi_bus_add(&device, pdevice, chandle,
						   ACPI_BUS_TYPE_DEVICE);
				if (ACPI_FAILURE(ret)) {
					printk(KERN_ERR "%s: acpi_bus_add "
					       "failed (0x%x) for slot %d "
					       "func %d\n", __func__,
					       ret, (int)(adr>>16),
					       (int)(adr&0xffff));
					/* try to continue on */
				} else {
					acpi_bus_start(device);
				}
			}
		}
	}

	/* Call the driver for the new device */
	pci_bus_add_devices(slot->pci_bus);
	/* Call the drivers for the new devices subordinate to PPB */
	if (new_ppb)
		pci_bus_add_devices(new_bus);

	mutex_unlock(&sn_hotplug_mutex);

	if (rc == 0)
		dev_dbg(&slot->pci_bus->self->dev,
			"insert operation successful\n");
	else
		dev_dbg(&slot->pci_bus->self->dev,
			"insert operation failed rc = %d\n", rc);

	return rc;
}

static int disable_slot(struct hotplug_slot *bss_hotplug_slot)
{
	struct slot *slot = bss_hotplug_slot->private;
	struct pci_dev *dev;
	int func;
	int rc;
	acpi_owner_id ssdt_id = 0;

	/* Acquire update access to the bus */
	mutex_lock(&sn_hotplug_mutex);

	/* is it okay to bring this slot down? */
	rc = sn_slot_disable(bss_hotplug_slot, slot->device_num,
			     PCI_REQ_SLOT_ELIGIBLE);
	if (rc)
		goto leaving;

	/* free the ACPI resources for the slot */
	if (SN_ACPI_BASE_SUPPORT() &&
            PCI_CONTROLLER(slot->pci_bus)->acpi_handle) {
		unsigned long long adr;
		struct acpi_device *device;
		acpi_handle phandle;
		acpi_handle chandle = NULL;
		acpi_handle rethandle;
		acpi_status ret;

		/* Get the rootbus node pointer */
		phandle = PCI_CONTROLLER(slot->pci_bus)->acpi_handle;

		/*
		 * Walk the rootbus node's immediate children looking for
		 * the slot's device node(s). There can be more than
		 * one for multifunction devices.
		 */
		for (;;) {
			rethandle = NULL;
			ret = acpi_get_next_object(ACPI_TYPE_DEVICE,
						   phandle, chandle,
						   &rethandle);

			if (ret == AE_NOT_FOUND || rethandle == NULL)
				break;

			chandle = rethandle;

			ret = acpi_evaluate_integer(chandle,
						    METHOD_NAME__ADR,
						    NULL, &adr);
			if (ACPI_SUCCESS(ret) &&
			    (adr>>16) == (slot->device_num + 1)) {
				/* retain the owner id */
				acpi_get_id(chandle, &ssdt_id);

				ret = acpi_bus_get_device(chandle,
							  &device);
				if (ACPI_SUCCESS(ret))
					acpi_bus_trim(device, 1);
			}
		}

	}

	/* Free the SN resources assigned to the Linux device.*/
	for (func = 0; func < 8;  func++) {
		dev = pci_get_slot(slot->pci_bus,
				   PCI_DEVFN(slot->device_num + 1,
				   	     PCI_FUNC(func)));
		if (dev) {
			sn_bus_free_data(dev);
			pci_remove_bus_device(dev);
			pci_dev_put(dev);
		}
	}

	/* Remove the SSDT for the slot from the ACPI namespace */
	if (SN_ACPI_BASE_SUPPORT() && ssdt_id) {
		acpi_status ret;
		ret = acpi_unload_table_id(ssdt_id);
		if (ACPI_FAILURE(ret)) {
			printk(KERN_ERR "%s: acpi_unload_table_id "
			       "failed (0x%x) for id %d\n",
			       __func__, ret, ssdt_id);
			/* try to continue on */
		}
	}

	/* free the collected sysdata pointers */
	sn_bus_free_sysdata();

	/* Deactivate slot */
	rc = sn_slot_disable(bss_hotplug_slot, slot->device_num,
			     PCI_REQ_SLOT_DISABLE);
 leaving:
	/* Release the bus lock */
	mutex_unlock(&sn_hotplug_mutex);

	return rc;
}

static inline int get_power_status(struct hotplug_slot *bss_hotplug_slot,
				   u8 *value)
{
	struct slot *slot = bss_hotplug_slot->private;
	struct pcibus_info *pcibus_info;
	u32 power;

	pcibus_info = SN_PCIBUS_BUSSOFT_INFO(slot->pci_bus);
	mutex_lock(&sn_hotplug_mutex);
	power = pcibus_info->pbi_enabled_devices & (1 << slot->device_num);
	*value = power ? 1 : 0;
	mutex_unlock(&sn_hotplug_mutex);
	return 0;
}

static void sn_release_slot(struct hotplug_slot *bss_hotplug_slot)
{
	kfree(bss_hotplug_slot->info);
	kfree(bss_hotplug_slot->private);
	kfree(bss_hotplug_slot);
}

static int sn_hotplug_slot_register(struct pci_bus *pci_bus)
{
	int device;
	struct pci_slot *pci_slot;
	struct hotplug_slot *bss_hotplug_slot;
	char name[SN_SLOT_NAME_SIZE];
	int rc = 0;

	/*
	 * Currently only four devices are supported,
	 * in the future there maybe more -- up to 32.
	 */

	for (device = 0; device < SN_MAX_HP_SLOTS ; device++) {
		if (sn_pci_slot_valid(pci_bus, device) != 1)
			continue;

		bss_hotplug_slot = kzalloc(sizeof(*bss_hotplug_slot),
					   GFP_KERNEL);
		if (!bss_hotplug_slot) {
			rc = -ENOMEM;
			goto alloc_err;
		}

		bss_hotplug_slot->info =
			kzalloc(sizeof(struct hotplug_slot_info),
				GFP_KERNEL);
		if (!bss_hotplug_slot->info) {
			rc = -ENOMEM;
			goto alloc_err;
		}

		if (sn_hp_slot_private_alloc(bss_hotplug_slot,
					     pci_bus, device, name)) {
			rc = -ENOMEM;
			goto alloc_err;
		}
		bss_hotplug_slot->ops = &sn_hotplug_slot_ops;
		bss_hotplug_slot->release = &sn_release_slot;

		rc = pci_hp_register(bss_hotplug_slot, pci_bus, device, name);
		if (rc)
			goto register_err;

		pci_slot = bss_hotplug_slot->pci_slot;
		rc = sysfs_create_file(&pci_slot->kobj,
				       &sn_slot_path_attr.attr);
		if (rc)
			goto register_err;
	}
	dev_dbg(&pci_bus->self->dev, "Registered bus with hotplug\n");
	return rc;

register_err:
	dev_dbg(&pci_bus->self->dev, "bus failed to register with err = %d\n",
		rc);

alloc_err:
	if (rc == -ENOMEM)
		dev_dbg(&pci_bus->self->dev, "Memory allocation error\n");

	/* destroy THIS element */
	if (bss_hotplug_slot)
		sn_release_slot(bss_hotplug_slot);

	/* destroy anything else on the list */
	while ((bss_hotplug_slot = sn_hp_destroy()))
		pci_hp_deregister(bss_hotplug_slot);

	return rc;
}

static int sn_pci_hotplug_init(void)
{
	struct pci_bus *pci_bus = NULL;
	int rc;
	int registered = 0;

	if (!sn_prom_feature_available(PRF_HOTPLUG_SUPPORT)) {
		printk(KERN_ERR "%s: PROM version does not support hotplug.\n",
		       __func__);
		return -EPERM;
	}

	INIT_LIST_HEAD(&sn_hp_list);

	while ((pci_bus = pci_find_next_bus(pci_bus))) {
		if (!pci_bus->sysdata)
			continue;

		rc = sn_pci_bus_valid(pci_bus);
		if (rc != 1) {
			dev_dbg(&pci_bus->self->dev, "not a valid hotplug bus\n");
			continue;
		}
		dev_dbg(&pci_bus->self->dev, "valid hotplug bus\n");

		rc = sn_hotplug_slot_register(pci_bus);
		if (!rc) {
			registered = 1;
		} else {
			registered = 0;
			break;
		}
	}

	return registered == 1 ? 0 : -ENODEV;
}

static void sn_pci_hotplug_exit(void)
{
	struct hotplug_slot *bss_hotplug_slot;

	while ((bss_hotplug_slot = sn_hp_destroy()))
		pci_hp_deregister(bss_hotplug_slot);

	if (!list_empty(&sn_hp_list))
		printk(KERN_ERR "%s: internal list is not empty\n", __FILE__);
}

module_init(sn_pci_hotplug_init);
module_exit(sn_pci_hotplug_exit);