diff options
author | Zhang Rui <rui.zhang@intel.com> | 2006-12-08 09:23:43 (GMT) |
---|---|---|
committer | Len Brown <len.brown@intel.com> | 2006-12-21 08:05:51 (GMT) |
commit | e49bd2dd5a503bb94fe2f2af45422b610940b75d (patch) | |
tree | 9ae6510a91f8b43197e32f08b328fa142e594b26 /drivers/acpi/scan.c | |
parent | ae8433324be16673c75951986dcf85f29c090557 (diff) | |
download | linux-fsl-qoriq-e49bd2dd5a503bb94fe2f2af45422b610940b75d.tar.xz |
ACPI: use PNPID:instance_no as bus_id of ACPI device
Previously we used the device name in the DSDT, but would
crash upon encountering a duplicate. Also, exposing the
DSDT device name to the user in a patch isn't a good idea,
because it is arbitrary.
After some discussion, we finally decided to use
"PNPID:instance_no" as the bus_id of ACPI devices.
Two attributes for each device are added at the same time,
the full pathname in ACPI namespace and hardware_id if it has.
NOTE: acpi_bus_id_list is used to keep the information of PNPID
and instance number of the given PNPID. Loop the
acpi_bus_id_list to find the instance_no of the same PNPID
when register a device. If failed, i.e. we don't have a
node with this PNPID, allocate one and link it to this list.
NOTE: Now I don't take the memory free work in charge.
If necessary, I can add a reference count in
struct acpi_device_bus_id, and check the reference and
when unregister a device, i.e. memory is freed when
the reference count of a given PNPID is 0.
Signed-off-by: Li Shaohua <shaohua.li@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Diffstat (limited to 'drivers/acpi/scan.c')
-rw-r--r-- | drivers/acpi/scan.c | 118 |
1 files changed, 109 insertions, 9 deletions
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index 9efe3e9..769e54b 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -21,9 +21,15 @@ extern struct acpi_device *acpi_root; #define ACPI_BUS_DEVICE_NAME "System Bus" static LIST_HEAD(acpi_device_list); +static LIST_HEAD(acpi_bus_id_list); DEFINE_SPINLOCK(acpi_device_lock); LIST_HEAD(acpi_wakeup_device_list); +struct acpi_device_bus_id{ + char bus_id[9]; + unsigned int instance_no; + struct list_head node; +}; static int acpi_eject_operation(acpi_handle handle, int lockable) { struct acpi_object_list arg_list; @@ -103,18 +109,61 @@ acpi_eject_store(struct device *d, struct device_attribute *attr, static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store); -static void acpi_device_setup_files(struct acpi_device *dev) +static ssize_t +acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) { + struct acpi_device *acpi_dev = to_acpi_device(dev); + + return sprintf(buf, "%s\n", acpi_dev->pnp.hardware_id); +} +static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL); + +static ssize_t +acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) { + struct acpi_device *acpi_dev = to_acpi_device(dev); + struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL}; + int result; + + result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path); + if(result) + goto end; + + result = sprintf(buf, "%s\n", (char*)path.pointer); + kfree(path.pointer); + end: + return result; +} +static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL); + +static int acpi_device_setup_files(struct acpi_device *dev) { acpi_status status; acpi_handle temp; + int result = 0; /* - * If device has _EJ0, 'eject' file is created that is used to trigger - * hot-removal function from userland. + * Devices gotten from FADT don't have a "path" attribute */ + if(dev->handle) { + result = device_create_file(&dev->dev, &dev_attr_path); + if(result) + goto end; + } + + if(dev->flags.hardware_id) { + result = device_create_file(&dev->dev, &dev_attr_hid); + if(result) + goto end; + } + + /* + * If device has _EJ0, 'eject' file is created that is used to trigger + * hot-removal function from userland. + */ status = acpi_get_handle(dev->handle, "_EJ0", &temp); if (ACPI_SUCCESS(status)) - device_create_file(&dev->dev, &dev_attr_eject); + result = device_create_file(&dev->dev, &dev_attr_eject); + end: + return result; } static void acpi_device_remove_files(struct acpi_device *dev) @@ -129,6 +178,11 @@ static void acpi_device_remove_files(struct acpi_device *dev) status = acpi_get_handle(dev->handle, "_EJ0", &temp); if (ACPI_SUCCESS(status)) device_remove_file(&dev->dev, &dev_attr_eject); + + if(dev->flags.hardware_id) + device_remove_file(&dev->dev, &dev_attr_hid); + if(dev->handle) + device_remove_file(&dev->dev, &dev_attr_path); } /* -------------------------------------------------------------------------- ACPI Bus operations @@ -260,9 +314,12 @@ static struct bus_type acpi_bus_type = { .uevent = acpi_device_uevent, }; -static void acpi_device_register(struct acpi_device *device, +static int acpi_device_register(struct acpi_device *device, struct acpi_device *parent) { + int result; + struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id; + int found = 0; /* * Linkage * ------- @@ -273,7 +330,33 @@ static void acpi_device_register(struct acpi_device *device, INIT_LIST_HEAD(&device->g_list); INIT_LIST_HEAD(&device->wakeup_list); + new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL); + if (!new_bus_id) { + printk(KERN_ERR PREFIX "Memory allocation error\n"); + return -ENOMEM; + } + spin_lock(&acpi_device_lock); + /* + * Find suitable bus_id and instance number in acpi_bus_id_list + * If failed, create one and link it into acpi_bus_id_list + */ + list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) { + if(!strcmp(acpi_device_bus_id->bus_id, device->flags.hardware_id? device->pnp.hardware_id : "PNPIDNON")) { + acpi_device_bus_id->instance_no ++; + found = 1; + kfree(new_bus_id); + break; + } + } + if(!found) { + acpi_device_bus_id = new_bus_id; + strcpy(acpi_device_bus_id->bus_id, device->flags.hardware_id ? device->pnp.hardware_id : "PNPIDNON"); + acpi_device_bus_id->instance_no = 0; + list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list); + } + sprintf(device->dev.bus_id, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no); + if (device->parent) { list_add_tail(&device->node, &device->parent->children); list_add_tail(&device->g_list, &device->parent->g_list); @@ -287,12 +370,29 @@ static void acpi_device_register(struct acpi_device *device, device->dev.parent = &parent->dev; device->dev.bus = &acpi_bus_type; device_initialize(&device->dev); - sprintf(device->dev.bus_id, "%s", device->pnp.bus_id); device->dev.release = &acpi_device_release; - device_add(&device->dev); + result = device_add(&device->dev); + if(result) { + printk("Error adding device %s", device->dev.bus_id); + goto end; + } + + result = acpi_device_setup_files(device); + if(result) + ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error creating sysfs interface for device %s\n", device->dev.bus_id)); - acpi_device_setup_files(device); device->removal_type = ACPI_BUS_REMOVAL_NORMAL; + return 0; + end: + spin_lock(&acpi_device_lock); + if (device->parent) { + list_del(&device->node); + list_del(&device->g_list); + } else + list_del(&device->g_list); + list_del(&device->wakeup_list); + spin_unlock(&acpi_device_lock); + return result; } static void acpi_device_unregister(struct acpi_device *device, int type) @@ -1035,7 +1135,7 @@ acpi_add_single_object(struct acpi_device **child, acpi_device_get_debug_info(device, handle, type); - acpi_device_register(device, parent); + result = acpi_device_register(device, parent); end: if (!result) |