From bf325f9538d8c89312be305b9779edbcb436af00 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 25 Nov 2010 00:10:44 +0100 Subject: ACPI / PM: Register power resource devices as soon as they are needed Depending on the organization of the ACPI namespace, power resource device objects may generally be scanned after the "regular" device objects that they are referred from through _PRn. This, in turn, may cause acpi_bus_get_power_flags() to attempt to access them through acpi_bus_init_power() before they are registered (and initialized by acpi_power_driver). [This is not a theoretical issue, it actually happens for one PnP device on my testbed HP nx6325.] To fix this problem, make acpi_bus_get_power_flags() attempt to register power resource devices as soon as they have been found in the _PRn output for any other devices. Signed-off-by: Rafael J. Wysocki Signed-off-by: Len Brown --- drivers/acpi/scan.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index 2951a27303cb..cb7956c23ca4 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -847,6 +847,8 @@ end: return 0; } +static void acpi_bus_add_power_resource(acpi_handle handle); + static int acpi_bus_get_power_flags(struct acpi_device *device) { acpi_status status = 0; @@ -875,8 +877,12 @@ static int acpi_bus_get_power_flags(struct acpi_device *device) acpi_evaluate_reference(device->handle, object_name, NULL, &ps->resources); if (ps->resources.count) { + int j; + device->power.flags.power_resources = 1; ps->flags.valid = 1; + for (j = 0; j < ps->resources.count; j++) + acpi_bus_add_power_resource(ps->resources.handles[j]); } /* Evaluate "_PSx" to see if we can do explicit sets */ @@ -1323,6 +1329,20 @@ end: #define ACPI_STA_DEFAULT (ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED | \ ACPI_STA_DEVICE_UI | ACPI_STA_DEVICE_FUNCTIONING) +static void acpi_bus_add_power_resource(acpi_handle handle) +{ + struct acpi_bus_ops ops = { + .acpi_op_add = 1, + .acpi_op_start = 1, + }; + struct acpi_device *device = NULL; + + acpi_bus_get_device(handle, &device); + if (!device) + acpi_add_single_object(&device, handle, ACPI_BUS_TYPE_POWER, + ACPI_STA_DEFAULT, &ops); +} + static int acpi_bus_type_and_status(acpi_handle handle, int *type, unsigned long long *sta) { -- cgit v1.2.2