[PATCH v2 07/12] cxl/acpi: Add a device_lock() lock class for the root platform device

[Dan Williams]

Now that the device-core can start validating lockdep usage after the
device has been added, use that capability to validate usage of
device_lock() against the ACPI0017 device relative to other subsystem
locks.

The 'enum cxl_lock_class' definition moves outside of the ifdef guard to
support device_set_lock_class() called from cxl_acpi_probe().

Cc: Alison Schofield <alison.schofield@xxxxxxxxx>
Cc: Vishal Verma <vishal.l.verma@xxxxxxxxx>
Cc: Ira Weiny <ira.weiny@xxxxxxxxx>
Cc: Ben Widawsky <ben.widawsky@xxxxxxxxx>
Reviewed-by: Dave Jiang <dave.jiang@xxxxxxxxx>
Reviewed-by: Kevin Tian <kevin.tian@xxxxxxxxx>
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
---
 drivers/cxl/acpi.c |    1 +
 drivers/cxl/cxl.h  |    3 ++-
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/cxl/acpi.c b/drivers/cxl/acpi.c
index d15a6aec0331..ef5c3252bdb2 100644
--- a/drivers/cxl/acpi.c
+++ b/drivers/cxl/acpi.c
@@ -283,6 +283,7 @@ static int cxl_acpi_probe(struct platform_device *pdev)
 	struct acpi_device *adev = ACPI_COMPANION(host);
 	struct cxl_cfmws_context ctx;
 
+	device_set_lock_class(&pdev->dev, CXL_ROOT_LOCK);
 	root_port = devm_cxl_add_port(host, host, CXL_RESOURCE_NONE, NULL);
 	if (IS_ERR(root_port))
 		return PTR_ERR(root_port);
diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index fddbcb380e84..05dc4c081ad2 100644
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -405,9 +405,9 @@ struct cxl_nvdimm_bridge *cxl_find_nvdimm_bridge(struct cxl_nvdimm *cxl_nvd);
 #define __mock static
 #endif
 
-#ifdef CONFIG_PROVE_CXL_LOCKING
 enum cxl_lock_class {
 	CXL_ANON_LOCK,
+	CXL_ROOT_LOCK,
 	CXL_NVDIMM_LOCK,
 	CXL_NVDIMM_BRIDGE_LOCK,
 	/*
@@ -423,6 +423,7 @@ enum cxl_lock_class {
 	 */
 };
 
+#ifdef CONFIG_PROVE_CXL_LOCKING
 static inline int clamp_lock_class(struct device *dev, int lock_class)
 {
 	if (lock_class >= MAX_LOCKDEP_SUBCLASSES) {