[PATCH v5 06/17] ACPI: scan: Define weak function to populate dependencies

Sunil V L
2024-05-01T12:18:51Z

Some architectures like RISC-V need to add dependencies without explicit
_DEP. Define a weak function which can be implemented by the architecture.

Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
---
drivers/acpi/scan.c | 11 +++++++++++
include/acpi/acpi_bus.h | 1 +
2 files changed, 12 insertions(+)

diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index beded069cb0a..3eeb4ce39fcc 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -2068,11 +2068,22 @@ int acpi_scan_add_dep(acpi_handle handle, struct acpi_handle_list *dep_devices)
return count;
}

+u32 __weak arch_acpi_add_auto_dep(acpi_handle handle) { return 0; }
+
static u32 acpi_scan_check_dep(acpi_handle handle)
{
struct acpi_handle_list dep_devices;
u32 count = 0;

+ /*
+ * Some architectures like RISC-V need to add dependencies for
+ * all devices which use GSI to the interrupt controller so that
+ * interrupt controller is probed before any of those devices.
+ * Instead of mandating _DEP on all the devices, detect the
+ * dependency and add automatically.
+ */
+ count += arch_acpi_add_auto_dep(handle);
+
/*
* Check for _HID here to avoid deferring the enumeration of:
* 1. PCI devices.
diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index 28a9b87c23fa..5fba4075d764 100644
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -994,6 +994,7 @@ static inline void acpi_put_acpi_dev(struct acpi_device *adev)
int acpi_wait_for_acpi_ipmi(void);

int acpi_scan_add_dep(acpi_handle handle, struct acpi_handle_list *dep_devices);
+u32 arch_acpi_add_auto_dep(acpi_handle handle);
#else /* CONFIG_ACPI */

static inline int register_acpi_bus_type(void *bus) { return 0; }
--
2.40.1