From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> If the special PRP0001 device ID is present in the given device's list of ACPI/PNP IDs and the device has a valid "compatible" property in the _DSD, it should be enumerated using the default mechanism, unless some scan handlers match the IDs preceding PRP0001 in the device's list of ACPI/PNP IDs. In addition to that, no scan handlers matching the IDs following PRP0001 in that list should be attached to the device. To make that happen, define a scan handler that will match PRP0001 and trigger the default enumeration for the matching devices if the "compatible" property is present for them. Since that requires the check for platform_id and device->handler to be removed from acpi_default_enumeration(), move the fallback invocation of acpi_default_enumeration() to acpi_bus_attach() (after it's checked if there's a matching ACPI driver for the device), which is a better place to call it, and do the platform_id check in there too (device->handler is guaranteed to be unset at the point where the function is looking for a matching ACPI driver). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> Acked-by: Darren Hart <dvhart@xxxxxxxxxxxxxxx> --- The change from the original patch is to change the scan handler behavior to make it return 1 also if the "compatible" property is not present, in which case the additional scan handlers should not trigger too *and* the default enumeration should not trigger either (as there's no ID to match to), which will allow things like auxiliary nodes (think GPIO buttons/LEDs etc) to be easily represented. Darren, I've tentatively added your Acked-by tag to this one, please let me know if that's not appropriate. Rafael --- drivers/acpi/scan.c | 33 ++++++++++++++++++++++++++++----- 1 file changed, 28 insertions(+), 5 deletions(-) Index: linux-pm/drivers/acpi/scan.c =================================================================== --- linux-pm.orig/drivers/acpi/scan.c +++ linux-pm/drivers/acpi/scan.c @@ -2388,9 +2388,6 @@ static void acpi_default_enumeration(str struct list_head resource_list; bool is_spi_i2c_slave = false; - if (!device->pnp.type.platform_id || device->handler) - return; - /* * Do not enemerate SPI/I2C slaves as they will be enuerated by their * respective parents. @@ -2403,6 +2400,29 @@ static void acpi_default_enumeration(str acpi_create_platform_device(device); } +static const struct acpi_device_id generic_device_ids[] = { + {"PRP0001", }, + {"", }, +}; + +static int acpi_generic_device_attach(struct acpi_device *adev, + const struct acpi_device_id *not_used) +{ + /* + * Since PRP0001 is the only ID handled here, the test below can be + * unconditional. + */ + if (adev->data.of_compatible) + acpi_default_enumeration(adev); + + return 1; +} + +static struct acpi_scan_handler generic_device_handler = { + .ids = generic_device_ids, + .attach = acpi_generic_device_attach, +}; + static int acpi_scan_attach_handler(struct acpi_device *device) { struct acpi_hardware_id *hwid; @@ -2428,8 +2448,6 @@ static int acpi_scan_attach_handler(stru break; } } - if (!ret) - acpi_default_enumeration(device); return ret; } @@ -2471,6 +2489,9 @@ static void acpi_bus_attach(struct acpi_ ret = device_attach(&device->dev); if (ret < 0) return; + + if (!ret && device->pnp.type.platform_id) + acpi_default_enumeration(device); } device->flags.visited = true; @@ -2629,6 +2650,8 @@ int __init acpi_scan_init(void) acpi_pnp_init(); acpi_int340x_thermal_init(); + acpi_scan_add_handler(&generic_device_handler); + mutex_lock(&acpi_scan_lock); /* * Enumerate devices in the ACPI namespace. -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html