diff options
Diffstat (limited to 'drivers/acpi/glue.c')
| -rw-r--r-- | drivers/acpi/glue.c | 360 | 
1 files changed, 360 insertions, 0 deletions
| diff --git a/drivers/acpi/glue.c b/drivers/acpi/glue.c new file mode 100644 index 000000000000..770cfc8b17e0 --- /dev/null +++ b/drivers/acpi/glue.c @@ -0,0 +1,360 @@ +/* + * Link physical devices with ACPI devices support + * + * Copyright (c) 2005 David Shaohua Li <shaohua.li@intel.com> + * Copyright (c) 2005 Intel Corp. + * + * This file is released under the GPLv2. + */ +#include <linux/init.h> +#include <linux/list.h> +#include <linux/device.h> +#include <linux/rwsem.h> +#include <linux/acpi.h> + +#define ACPI_GLUE_DEBUG	0 +#if ACPI_GLUE_DEBUG +#define DBG(x...) printk(PREFIX x) +#else +#define DBG(x...) +#endif +static LIST_HEAD(bus_type_list); +static DECLARE_RWSEM(bus_type_sem); + +int register_acpi_bus_type(struct acpi_bus_type *type) +{ +	if (acpi_disabled) +		return -ENODEV; +	if (type && type->bus && type->find_device) { +		down_write(&bus_type_sem); +		list_add_tail(&type->list, &bus_type_list); +		up_write(&bus_type_sem); +		printk(KERN_INFO PREFIX "bus type %s registered\n", type->bus->name); +		return 0; +	} +	return -ENODEV; +} + +EXPORT_SYMBOL(register_acpi_bus_type); + +int unregister_acpi_bus_type(struct acpi_bus_type *type) +{ +	if (acpi_disabled) +		return 0; +	if (type) { +		down_write(&bus_type_sem); +		list_del_init(&type->list); +		up_write(&bus_type_sem); +		printk(KERN_INFO PREFIX "ACPI bus type %s unregistered\n", type->bus->name); +		return 0; +	} +	return -ENODEV; +} + +EXPORT_SYMBOL(unregister_acpi_bus_type); + +static struct acpi_bus_type *acpi_get_bus_type(struct bus_type *type) +{ +	struct acpi_bus_type *tmp, *ret = NULL; + +	down_read(&bus_type_sem); +	list_for_each_entry(tmp, &bus_type_list, list) { +		if (tmp->bus == type) { +			ret = tmp; +			break; +		} +	} +	up_read(&bus_type_sem); +	return ret; +} + +static int acpi_find_bridge_device(struct device *dev, acpi_handle * handle) +{ +	struct acpi_bus_type *tmp; +	int ret = -ENODEV; + +	down_read(&bus_type_sem); +	list_for_each_entry(tmp, &bus_type_list, list) { +		if (tmp->find_bridge && !tmp->find_bridge(dev, handle)) { +			ret = 0; +			break; +		} +	} +	up_read(&bus_type_sem); +	return ret; +} + +/* Get PCI root bridge's handle from its segment and bus number */ +struct acpi_find_pci_root { +	unsigned int seg; +	unsigned int bus; +	acpi_handle handle; +}; + +static acpi_status +do_root_bridge_busnr_callback(struct acpi_resource *resource, void *data) +{ +	int *busnr = (int *)data; +	struct acpi_resource_address64 address; + +	if (resource->id != ACPI_RSTYPE_ADDRESS16 && +	    resource->id != ACPI_RSTYPE_ADDRESS32 && +	    resource->id != ACPI_RSTYPE_ADDRESS64) +		return AE_OK; + +	acpi_resource_to_address64(resource, &address); +	if ((address.address_length > 0) && +	    (address.resource_type == ACPI_BUS_NUMBER_RANGE)) +		*busnr = address.min_address_range; + +	return AE_OK; +} + +static int get_root_bridge_busnr(acpi_handle handle) +{ +	acpi_status status; +	int bus, bbn; +	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; + +	acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer); + +	status = acpi_evaluate_integer(handle, METHOD_NAME__BBN, NULL, +				       (unsigned long *)&bbn); +	if (status == AE_NOT_FOUND) { +		/* Assume bus = 0 */ +		printk(KERN_INFO PREFIX +		       "Assume root bridge [%s] bus is 0\n", +		       (char *)buffer.pointer); +		status = AE_OK; +		bbn = 0; +	} +	if (ACPI_FAILURE(status)) { +		bbn = -ENODEV; +		goto exit; +	} +	if (bbn > 0) +		goto exit; + +	/* _BBN in some systems return 0 for all root bridges */ +	bus = -1; +	status = acpi_walk_resources(handle, METHOD_NAME__CRS, +				     do_root_bridge_busnr_callback, &bus); +	/* If _CRS failed, we just use _BBN */ +	if (ACPI_FAILURE(status) || (bus == -1)) +		goto exit; +	/* We select _CRS */ +	if (bbn != bus) { +		printk(KERN_INFO PREFIX +		       "_BBN and _CRS returns different value for %s. Select _CRS\n", +		       (char *)buffer.pointer); +		bbn = bus; +	} +      exit: +	acpi_os_free(buffer.pointer); +	return bbn; +} + +static acpi_status +find_pci_rootbridge(acpi_handle handle, u32 lvl, void *context, void **rv) +{ +	struct acpi_find_pci_root *find = (struct acpi_find_pci_root *)context; +	unsigned long seg, bus; +	acpi_status status; +	int tmp; +	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; + +	acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer); + +	status = acpi_evaluate_integer(handle, METHOD_NAME__SEG, NULL, &seg); +	if (status == AE_NOT_FOUND) { +		/* Assume seg = 0 */ +		printk(KERN_INFO PREFIX +		       "Assume root bridge [%s] segment is 0\n", +		       (char *)buffer.pointer); +		status = AE_OK; +		seg = 0; +	} +	if (ACPI_FAILURE(status)) { +		status = AE_CTRL_DEPTH; +		goto exit; +	} + +	tmp = get_root_bridge_busnr(handle); +	if (tmp < 0) { +		printk(KERN_ERR PREFIX +		       "Find root bridge failed for %s\n", +		       (char *)buffer.pointer); +		status = AE_CTRL_DEPTH; +		goto exit; +	} +	bus = tmp; + +	if (seg == find->seg && bus == find->bus) +		find->handle = handle; +	status = AE_OK; +      exit: +	acpi_os_free(buffer.pointer); +	return status; +} + +acpi_handle acpi_get_pci_rootbridge_handle(unsigned int seg, unsigned int bus) +{ +	struct acpi_find_pci_root find = { seg, bus, NULL }; + +	acpi_get_devices(PCI_ROOT_HID_STRING, find_pci_rootbridge, &find, NULL); +	return find.handle; +} + +/* Get device's handler per its address under its parent */ +struct acpi_find_child { +	acpi_handle handle; +	acpi_integer address; +}; + +static acpi_status +do_acpi_find_child(acpi_handle handle, u32 lvl, void *context, void **rv) +{ +	acpi_status status; +	struct acpi_device_info *info; +	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; +	struct acpi_find_child *find = (struct acpi_find_child *)context; + +	status = acpi_get_object_info(handle, &buffer); +	if (ACPI_SUCCESS(status)) { +		info = buffer.pointer; +		if (info->address == find->address) +			find->handle = handle; +		acpi_os_free(buffer.pointer); +	} +	return AE_OK; +} + +acpi_handle acpi_get_child(acpi_handle parent, acpi_integer address) +{ +	struct acpi_find_child find = { NULL, address }; + +	if (!parent) +		return NULL; +	acpi_walk_namespace(ACPI_TYPE_DEVICE, parent, +			    1, do_acpi_find_child, &find, NULL); +	return find.handle; +} + +EXPORT_SYMBOL(acpi_get_child); + +/* Link ACPI devices with physical devices */ +static void acpi_glue_data_handler(acpi_handle handle, +				   u32 function, void *context) +{ +	/* we provide an empty handler */ +} + +/* Note: a success call will increase reference count by one */ +struct device *acpi_get_physical_device(acpi_handle handle) +{ +	acpi_status status; +	struct device *dev; + +	status = acpi_get_data(handle, acpi_glue_data_handler, (void **)&dev); +	if (ACPI_SUCCESS(status)) +		return get_device(dev); +	return NULL; +} + +EXPORT_SYMBOL(acpi_get_physical_device); + +static int acpi_bind_one(struct device *dev, acpi_handle handle) +{ +	acpi_status status; + +	if (dev->firmware_data) { +		printk(KERN_WARNING PREFIX +		       "Drivers changed 'firmware_data' for %s\n", dev->bus_id); +		return -EINVAL; +	} +	get_device(dev); +	status = acpi_attach_data(handle, acpi_glue_data_handler, dev); +	if (ACPI_FAILURE(status)) { +		put_device(dev); +		return -EINVAL; +	} +	dev->firmware_data = handle; + +	return 0; +} + +static int acpi_unbind_one(struct device *dev) +{ +	if (!dev->firmware_data) +		return 0; +	if (dev == acpi_get_physical_device(dev->firmware_data)) { +		/* acpi_get_physical_device increase refcnt by one */ +		put_device(dev); +		acpi_detach_data(dev->firmware_data, acpi_glue_data_handler); +		dev->firmware_data = NULL; +		/* acpi_bind_one increase refcnt by one */ +		put_device(dev); +	} else { +		printk(KERN_ERR PREFIX +		       "Oops, 'firmware_data' corrupt for %s\n", dev->bus_id); +	} +	return 0; +} + +static int acpi_platform_notify(struct device *dev) +{ +	struct acpi_bus_type *type; +	acpi_handle handle; +	int ret = -EINVAL; + +	if (!dev->bus || !dev->parent) { +		/* bridge devices genernally haven't bus or parent */ +		ret = acpi_find_bridge_device(dev, &handle); +		goto end; +	} +	type = acpi_get_bus_type(dev->bus); +	if (!type) { +		DBG("No ACPI bus support for %s\n", dev->bus_id); +		ret = -EINVAL; +		goto end; +	} +	if ((ret = type->find_device(dev, &handle)) != 0) +		DBG("Can't get handler for %s\n", dev->bus_id); +      end: +	if (!ret) +		acpi_bind_one(dev, handle); + +#if ACPI_GLUE_DEBUG +	if (!ret) { +		struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; + +		acpi_get_name(dev->firmware_data, ACPI_FULL_PATHNAME, &buffer); +		DBG("Device %s -> %s\n", dev->bus_id, (char *)buffer.pointer); +		acpi_os_free(buffer.pointer); +	} else +		DBG("Device %s -> No ACPI support\n", dev->bus_id); +#endif + +	return ret; +} + +static int acpi_platform_notify_remove(struct device *dev) +{ +	acpi_unbind_one(dev); +	return 0; +} + +static int __init init_acpi_device_notify(void) +{ +	if (acpi_disabled) +		return 0; +	if (platform_notify || platform_notify_remove) { +		printk(KERN_ERR PREFIX "Can't use platform_notify\n"); +		return 0; +	} +	platform_notify = acpi_platform_notify; +	platform_notify_remove = acpi_platform_notify_remove; +	return 0; +} + +arch_initcall(init_acpi_device_notify); | 
