From fc2e0a8326d1b21d11ef8213298e5302867fed2c Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 26 Aug 2014 01:29:21 +0200 Subject: [PATCH] ACPI / scan: Allow ACPI drivers to bind to PNP device objects We generally don't allow ACPI drivers to bind to ACPI device objects that companion "physical" device objects are created for to avoid situations in which two different drivers may attempt to handle one device at the same time. Recent ACPI device enumeration rework extended that approach to ACPI PNP devices by starting to use a scan handler for enumerating them. However, we previously allowed ACPI drivers to bind to ACPI device objects with existing PNP device companions and changing that led to functional regressions on some systems. For this reason, add a special check for PNP devices in acpi_device_probe() so that ACPI drivers can bind to ACPI device objects having existing PNP device companions as before. Fixes: eec15edbb0e1 (ACPI / PNP: use device ID list for PNPACPI device enumeration) Link: https://bugzilla.kernel.org/show_bug.cgi?id=81511 Link: https://bugzilla.kernel.org/show_bug.cgi?id=81971 Reported-by: Gabriele Mazzotta Reported-by: Dirk Griesbach Cc: 3.16+ # 3.16+ Signed-off-by: Rafael J. Wysocki --- drivers/acpi/scan.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index 0a817ad24f16..fd17fe7f93f2 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -975,7 +975,7 @@ static int acpi_device_probe(struct device *dev) struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver); int ret; - if (acpi_dev->handler) + if (acpi_dev->handler && !acpi_is_pnp_device(acpi_dev)) return -EINVAL; if (!acpi_drv->ops.add)