acpiphp_glue.c

audio driver for hotplug pci on linux 2.6.27

 * If a slot doesn't have _STA and if any one of its functions'
 * configuration space is configured, return 0x0f as a _STA.
 *
 * Otherwise return 0.
 */
static unsigned int get_slot_status(struct acpiphp_slot *slot)
{
	acpi_status status;
	unsigned long long sta = 0;
	u32 dvid;
	struct list_head *l;
	struct acpiphp_func *func;

	list_for_each (l, &slot->funcs) {
		func = list_entry(l, struct acpiphp_func, sibling);

		if (func->flags & FUNC_HAS_STA) {
			status = acpi_evaluate_integer(func->handle, "_STA", NULL, &sta);
			if (ACPI_SUCCESS(status) && sta)
				break;
		} else {
			pci_bus_read_config_dword(slot->bridge->pci_bus,
						  PCI_DEVFN(slot->device,
							    func->function),
						  PCI_VENDOR_ID, &dvid);
			if (dvid != 0xffffffff) {
				sta = ACPI_STA_ALL;
				break;
			}
		}
	}

	return (unsigned int)sta;
}

/**
 * acpiphp_eject_slot - physically eject the slot
 * @slot: ACPI PHP slot
 */
int acpiphp_eject_slot(struct acpiphp_slot *slot)
{
	acpi_status status;
	struct acpiphp_func *func;
	struct list_head *l;
	struct acpi_object_list arg_list;
	union acpi_object arg;

	list_for_each (l, &slot->funcs) {
		func = list_entry(l, struct acpiphp_func, sibling);

		/* We don't want to call _EJ0 on non-existing functions. */
		if ((func->flags & FUNC_HAS_EJ0)) {
			/* _EJ0 method take one argument */
			arg_list.count = 1;
			arg_list.pointer = &arg;
			arg.type = ACPI_TYPE_INTEGER;
			arg.integer.value = 1;

			status = acpi_evaluate_object(func->handle, "_EJ0", &arg_list, NULL);
			if (ACPI_FAILURE(status)) {
				warn("%s: _EJ0 failed\n", __func__);
				return -1;
			} else
				break;
		}
	}
	return 0;
}

/**
 * acpiphp_check_bridge - re-enumerate devices
 * @bridge: where to begin re-enumeration
 *
 * Iterate over all slots under this bridge and make sure that if a
 * card is present they are enabled, and if not they are disabled.
 */
static int acpiphp_check_bridge(struct acpiphp_bridge *bridge)
{
	struct acpiphp_slot *slot;
	int retval = 0;
	int enabled, disabled;

	enabled = disabled = 0;

	for (slot = bridge->slots; slot; slot = slot->next) {
		unsigned int status = get_slot_status(slot);
		if (slot->flags & SLOT_ENABLED) {
			if (status == ACPI_STA_ALL)
				continue;
			retval = acpiphp_disable_slot(slot);
			if (retval) {
				err("Error occurred in disabling\n");
				goto err_exit;
			} else {
				acpiphp_eject_slot(slot);
			}
			disabled++;
		} else {
			if (status != ACPI_STA_ALL)
				continue;
			retval = acpiphp_enable_slot(slot);
			if (retval) {
				err("Error occurred in enabling\n");
				goto err_exit;
			}
			enabled++;
		}
	}

	dbg("%s: %d enabled, %d disabled\n", __func__, enabled, disabled);

 err_exit:
	return retval;
}

static void program_hpp(struct pci_dev *dev, struct acpiphp_bridge *bridge)
{
	u16 pci_cmd, pci_bctl;
	struct pci_dev *cdev;

	/* Program hpp values for this device */
	if (!(dev->hdr_type == PCI_HEADER_TYPE_NORMAL ||
			(dev->hdr_type == PCI_HEADER_TYPE_BRIDGE &&
			(dev->class >> 8) == PCI_CLASS_BRIDGE_PCI)))
		return;

	if ((dev->class >> 8) == PCI_CLASS_BRIDGE_HOST)
		return;

	pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE,
			bridge->hpp.t0->cache_line_size);
	pci_write_config_byte(dev, PCI_LATENCY_TIMER,
			bridge->hpp.t0->latency_timer);
	pci_read_config_word(dev, PCI_COMMAND, &pci_cmd);
	if (bridge->hpp.t0->enable_serr)
		pci_cmd |= PCI_COMMAND_SERR;
	else
		pci_cmd &= ~PCI_COMMAND_SERR;
	if (bridge->hpp.t0->enable_perr)
		pci_cmd |= PCI_COMMAND_PARITY;
	else
		pci_cmd &= ~PCI_COMMAND_PARITY;
	pci_write_config_word(dev, PCI_COMMAND, pci_cmd);

	/* Program bridge control value and child devices */
	if ((dev->class >> 8) == PCI_CLASS_BRIDGE_PCI) {
		pci_write_config_byte(dev, PCI_SEC_LATENCY_TIMER,
				bridge->hpp.t0->latency_timer);
		pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &pci_bctl);
		if (bridge->hpp.t0->enable_serr)
			pci_bctl |= PCI_BRIDGE_CTL_SERR;
		else
			pci_bctl &= ~PCI_BRIDGE_CTL_SERR;
		if (bridge->hpp.t0->enable_perr)
			pci_bctl |= PCI_BRIDGE_CTL_PARITY;
		else
			pci_bctl &= ~PCI_BRIDGE_CTL_PARITY;
		pci_write_config_word(dev, PCI_BRIDGE_CONTROL, pci_bctl);
		if (dev->subordinate) {
			list_for_each_entry(cdev, &dev->subordinate->devices,
					bus_list)
				program_hpp(cdev, bridge);
		}
	}
}

static void acpiphp_set_hpp_values(acpi_handle handle, struct pci_bus *bus)
{
	struct acpiphp_bridge bridge;
	struct pci_dev *dev;

	memset(&bridge, 0, sizeof(bridge));
	bridge.handle = handle;
	bridge.pci_bus = bus;
	bridge.pci_dev = bus->self;
	decode_hpp(&bridge);
	list_for_each_entry(dev, &bus->devices, bus_list)
		program_hpp(dev, &bridge);

}

/*
 * Remove devices for which we could not assign resources, call
 * arch specific code to fix-up the bus
 */
static void acpiphp_sanitize_bus(struct pci_bus *bus)
{
	struct pci_dev *dev;
	int i;
	unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM;

	list_for_each_entry(dev, &bus->devices, bus_list) {
		for (i=0; i<PCI_BRIDGE_RESOURCES; i++) {
			struct resource *res = &dev->resource[i];
			if ((res->flags & type_mask) && !res->start &&
					res->end) {
				/* Could not assign a required resources
				 * for this device, remove it */
				pci_remove_bus_device(dev);
				break;
			}
		}
	}
}

/* Program resources in newly inserted bridge */
static int acpiphp_configure_bridge (acpi_handle handle)
{
	struct acpi_pci_id pci_id;
	struct pci_bus *bus;

	if (ACPI_FAILURE(acpi_get_pci_id(handle, &pci_id))) {
		err("cannot get PCI domain and bus number for bridge\n");
		return -EINVAL;
	}
	bus = pci_find_bus(pci_id.segment, pci_id.bus);
	if (!bus) {
		err("cannot find bus %d:%d\n",
				pci_id.segment, pci_id.bus);
		return -EINVAL;
	}

	pci_bus_size_bridges(bus);
	pci_bus_assign_resources(bus);
	acpiphp_sanitize_bus(bus);
	acpiphp_set_hpp_values(handle, bus);
	pci_enable_bridges(bus);
	acpiphp_configure_ioapics(handle);
	return 0;
}

static void handle_bridge_insertion(acpi_handle handle, u32 type)
{
	struct acpi_device *device, *pdevice;
	acpi_handle phandle;

	if ((type != ACPI_NOTIFY_BUS_CHECK) &&
			(type != ACPI_NOTIFY_DEVICE_CHECK)) {
		err("unexpected notification type %d\n", type);
		return;
	}

	acpi_get_parent(handle, &phandle);
	if (acpi_bus_get_device(phandle, &pdevice)) {
		dbg("no parent device, assuming NULL\n");
		pdevice = NULL;
	}
	if (acpi_bus_add(&device, pdevice, handle, ACPI_BUS_TYPE_DEVICE)) {
		err("cannot add bridge to acpi list\n");
		return;
	}
	if (!acpiphp_configure_bridge(handle) &&
		!acpi_bus_start(device))
		add_bridge(handle);
	else
		err("cannot configure and start bridge\n");

}

/*
 * ACPI event handlers
 */

static acpi_status
count_sub_bridges(acpi_handle handle, u32 lvl, void *context, void **rv)
{
	int *count = (int *)context;
	struct acpiphp_bridge *bridge;

	bridge = acpiphp_handle_to_bridge(handle);
	if (bridge)
		(*count)++;
	return AE_OK ;
}

static acpi_status
check_sub_bridges(acpi_handle handle, u32 lvl, void *context, void **rv)
{
	struct acpiphp_bridge *bridge;
	char objname[64];
	struct acpi_buffer buffer = { .length = sizeof(objname),
				      .pointer = objname };

	bridge = acpiphp_handle_to_bridge(handle);
	if (bridge) {
		acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
		dbg("%s: re-enumerating slots under %s\n",
			__func__, objname);
		acpiphp_check_bridge(bridge);
	}
	return AE_OK ;
}

/**
 * handle_hotplug_event_bridge - handle ACPI event on bridges
 * @handle: Notify()'ed acpi_handle
 * @type: Notify code
 * @context: pointer to acpiphp_bridge structure
 *
 * Handles ACPI event notification on {host,p2p} bridges.
 */
static void handle_hotplug_event_bridge(acpi_handle handle, u32 type, void *context)
{
	struct acpiphp_bridge *bridge;
	char objname[64];
	struct acpi_buffer buffer = { .length = sizeof(objname),
				      .pointer = objname };
	struct acpi_device *device;
	int num_sub_bridges = 0;

	if (acpi_bus_get_device(handle, &device)) {
		/* This bridge must have just been physically inserted */
		handle_bridge_insertion(handle, type);
		return;
	}

	bridge = acpiphp_handle_to_bridge(handle);
	if (type == ACPI_NOTIFY_BUS_CHECK) {
		acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, ACPI_UINT32_MAX,
			count_sub_bridges, &num_sub_bridges, NULL);
	}

	if (!bridge && !num_sub_bridges) {
		err("cannot get bridge info\n");
		return;
	}

	acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);

	switch (type) {
	case ACPI_NOTIFY_BUS_CHECK:
		/* bus re-enumerate */
		dbg("%s: Bus check notify on %s\n", __func__, objname);
		if (bridge) {
			dbg("%s: re-enumerating slots under %s\n",
				__func__, objname);
			acpiphp_check_bridge(bridge);
		}
		if (num_sub_bridges)
			acpi_walk_namespace(ACPI_TYPE_DEVICE, handle,
				ACPI_UINT32_MAX, check_sub_bridges, NULL, NULL);
		break;

	case ACPI_NOTIFY_DEVICE_CHECK:
		/* device check */
		dbg("%s: Device check notify on %s\n", __func__, objname);
		acpiphp_check_bridge(bridge);
		break;

	case ACPI_NOTIFY_DEVICE_WAKE:
		/* wake event */
		dbg("%s: Device wake notify on %s\n", __func__, objname);
		break;

	case ACPI_NOTIFY_EJECT_REQUEST:
		/* request device eject */
		dbg("%s: Device eject notify on %s\n", __func__, objname);
		if ((bridge->type != BRIDGE_TYPE_HOST) &&
		    (bridge->flags & BRIDGE_HAS_EJ0)) {
			struct acpiphp_slot *slot;
			slot = bridge->func->slot;
			if (!acpiphp_disable_slot(slot))
				acpiphp_eject_slot(slot);
		}
		break;

	case ACPI_NOTIFY_FREQUENCY_MISMATCH:
		printk(KERN_ERR "Device %s cannot be configured due"
				" to a frequency mismatch\n", objname);
		break;

	case ACPI_NOTIFY_BUS_MODE_MISMATCH:
		printk(KERN_ERR "Device %s cannot be configured due"
				" to a bus mode mismatch\n", objname);
		break;

	case ACPI_NOTIFY_POWER_FAULT:
		printk(KERN_ERR "Device %s has suffered a power fault\n",
				objname);
		break;

	default:
		warn("notify_handler: unknown event type 0x%x for %s\n", type, objname);
		break;
	}
}

/**
 * handle_hotplug_event_func - handle ACPI event on functions (i.e. slots)
 * @handle: Notify()'ed acpi_handle
 * @type: Notify code
 * @context: pointer to acpiphp_func structure
 *
 * Handles ACPI event notification on slots.
 */
static void handle_hotplug_event_func(acpi_handle handle, u32 type, void *context)
{
	struct acpiphp_func *func;
	char objname[64];
	struct acpi_buffer buffer = { .length = sizeof(objname),
				      .pointer = objname };

	acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);

	func = (struct acpiphp_func *)context;

	switch (type) {
	case ACPI_NOTIFY_BUS_CHECK:
		/* bus re-enumerate */
		dbg("%s: Bus check notify on %s\n", __func__, objname);
		acpiphp_enable_slot(func->slot);
		break;

	case ACPI_NOTIFY_DEVICE_CHECK:
		/* device check : re-enumerate from parent bus */
		dbg("%s: Device check notify on %s\n", __func__, objname);
		acpiphp_check_bridge(func->slot->bridge);
		break;

	case ACPI_NOTIFY_DEVICE_WAKE:
		/* wake event */
		dbg("%s: Device wake notify on %s\n", __func__, objname);
		break;

	case ACPI_NOTIFY_EJECT_REQUEST:
		/* request device eject */
		dbg("%s: Device eject notify on %s\n", __func__, objname);
		if (!(acpiphp_disable_slot(func->slot)))
			acpiphp_eject_slot(func->slot);
		break;

	default:
		warn("notify_handler: unknown event type 0x%x for %s\n", type, objname);
		break;
	}
}


static acpi_status
find_root_bridges(acpi_handle handle, u32 lvl, void *context, void **rv)
{
	int *count = (int *)context;

	if (acpi_root_bridge(handle)) {
		acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
				handle_hotplug_event_bridge, NULL);
			(*count)++;
	}
	return AE_OK ;
}

static struct acpi_pci_driver acpi_pci_hp_driver = {
	.add =		add_bridge,
	.remove =	remove_bridge,
};

/**
 * acpiphp_glue_init - initializes all PCI hotplug - ACPI glue data structures
 */
int __init acpiphp_glue_init(void)
{
	int num = 0;

	acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
			ACPI_UINT32_MAX, find_root_bridges, &num, NULL);

	if (num <= 0)
		return -1;
	else
		acpi_pci_register_driver(&acpi_pci_hp_driver);

	return 0;
}


/**
 * acpiphp_glue_exit - terminates all PCI hotplug - ACPI glue data structures
 *
 * This function frees all data allocated in acpiphp_glue_init().
 */
void  acpiphp_glue_exit(void)
{
	acpi_pci_unregister_driver(&acpi_pci_hp_driver);
}


/**
 * acpiphp_get_num_slots - count number of slots in a system
 */
int __init acpiphp_get_num_slots(void)
{
	struct acpiphp_bridge *bridge;
	int num_slots = 0;

	list_for_each_entry (bridge, &bridge_list, list) {
		dbg("Bus %04x:%02x has %d slot%s\n",
				pci_domain_nr(bridge->pci_bus),
				bridge->pci_bus->number, bridge->nr_slots,
				bridge->nr_slots == 1 ? "" : "s");
		num_slots += bridge->nr_slots;
	}

	dbg("Total %d slots\n", num_slots);
	return num_slots;
}


#if 0
/**
 * acpiphp_for_each_slot - call function for each slot
 * @fn: callback function
 * @data: context to be passed to callback function
 */
static int acpiphp_for_each_slot(acpiphp_callback fn, void *data)
{
	struct list_head *node;
	struct acpiphp_bridge *bridge;
	struct acpiphp_slot *slot;
	int retval = 0;

	list_for_each (node, &bridge_list) {
		bridge = (struct acpiphp_bridge *)node;
		for (slot = bridge->slots; slot; slot = slot->next) {
			retval = fn(slot, data);
			if (!retval)
				goto err_exit;
		}
	}

 err_exit:
	return retval;
}
#endif


/**
 * acpiphp_enable_slot - power on slot
 * @slot: ACPI PHP slot
 */
int acpiphp_enable_slot(struct acpiphp_slot *slot)
{
	int retval;

	mutex_lock(&slot->crit_sect);

	/* wake up all functions */
	retval = power_on_slot(slot);
	if (retval)
		goto err_exit;

	if (get_slot_status(slot) == ACPI_STA_ALL) {
		/* configure all functions */
		retval = enable_device(slot);
		if (retval)
			power_off_slot(slot);
	} else {
		dbg("%s: Slot status is not ACPI_STA_ALL\n", __func__);
		power_off_slot(slot);
	}

 err_exit:
	mutex_unlock(&slot->crit_sect);
	return retval;
}

/**
 * acpiphp_disable_slot - power off slot
 * @slot: ACPI PHP slot
 */
int acpiphp_disable_slot(struct acpiphp_slot *slot)
{
	int retval = 0;

	mutex_lock(&slot->crit_sect);

	/* unconfigure all functions */
	retval = disable_device(slot);
	if (retval)
		goto err_exit;

	/* power off all functions */
	retval = power_off_slot(slot);
	if (retval)
		goto err_exit;

 err_exit:
	mutex_unlock(&slot->crit_sect);
	return retval;
}


/*
 * slot enabled:  1
 * slot disabled: 0
 */
u8 acpiphp_get_power_status(struct acpiphp_slot *slot)
{
	return (slot->flags & SLOT_POWEREDON);
}


/*
 * latch   open:  1
 * latch closed:  0
 */
u8 acpiphp_get_latch_status(struct acpiphp_slot *slot)
{
	unsigned int sta;

	sta = get_slot_status(slot);

	return (sta & ACPI_STA_SHOW_IN_UI) ? 0 : 1;
}


/*
 * adapter presence : 1
 *          absence : 0
 */
u8 acpiphp_get_adapter_status(struct acpiphp_slot *slot)
{
	unsigned int sta;

	sta = get_slot_status(slot);

	return (sta == 0) ? 0 : 1;
}