From 87b85b3c8a4ac286d41a1c6419014b7562e4663b Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 6 Feb 2013 13:05:22 +0100 Subject: ACPI / scan: Follow priorities of IDs when matching scan handlers The IDs of ACPI device nodes stored in their pnp.ids member arrays are sorted by decreasing priority (i.e. the highest-priority ID is the first entry). This means that when matching scan handlers to device nodes, the namespace scanning code should walk the list of scan handlers for each device node ID instead of walking the list of device node IDs for each handler (the latter causes the first handler matching any of the device node IDs to be chosen, although there may be another handler matching an ID of a higher priority which should be preferred). Make the code follow this observation. This change has been suggested and justified by Toshi Kani. Signed-off-by: Rafael J. Wysocki Acked-by: Toshi Kani --- drivers/acpi/scan.c | 40 ++++++++++++++++++++++++++++------------ 1 file changed, 28 insertions(+), 12 deletions(-) diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index 360f1338749b..688b7f7c23dd 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -1553,26 +1553,42 @@ static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used, return AE_OK; } -static int acpi_scan_attach_handler(struct acpi_device *device) +static int acpi_scan_do_attach_handler(struct acpi_device *device, char *id) { struct acpi_scan_handler *handler; - int ret = 0; list_for_each_entry(handler, &acpi_scan_handlers_list, list_node) { - const struct acpi_device_id *id; + const struct acpi_device_id *devid; - id = __acpi_match_device(device, handler->ids); - if (!id) - continue; + for (devid = handler->ids; devid->id[0]; devid++) { + int ret; - ret = handler->attach(device, id); - if (ret > 0) { - device->handler = handler; - break; - } else if (ret < 0) { - break; + if (strcmp((char *)devid->id, id)) + continue; + + ret = handler->attach(device, devid); + if (ret > 0) { + device->handler = handler; + return ret; + } else if (ret < 0) { + return ret; + } } } + return 0; +} + +static int acpi_scan_attach_handler(struct acpi_device *device) +{ + struct acpi_hardware_id *hwid; + int ret = 0; + + list_for_each_entry(hwid, &device->pnp.ids, list) { + ret = acpi_scan_do_attach_handler(device, hwid->id); + if (ret) + break; + + } return ret; } -- cgit v1.2.3