spi: Export acpi_spi_find_controller_by_adev()

Export acpi_spi_find_controller_by_adev() so that ACPI glue code which
wants to dynamically create a spi_device using acpi_spi_device_alloc() or
spi_new_device() on a controller, to which the code does not already have
a reference, can find the controller.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20231014205314.59333-2-hdegoede@redhat.comSigned-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/spi.c

@@ -2523,8 +2523,6 @@ static void acpi_spi_parse_apple_properties(struct acpi_device *dev,
 		lookup->mode |= SPI_CPHA;
 }
 
-static struct spi_controller *acpi_spi_find_controller_by_adev(struct acpi_device *adev);
-
 static int acpi_spi_add_resource(struct acpi_resource *ares, void *data)
 {
 	struct acpi_spi_lookup *lookup = data;
@@ -4519,7 +4517,7 @@ static int spi_acpi_controller_match(struct device *dev, const void *data)
 	return ACPI_COMPANION(dev->parent) == data;
 }
 
-static struct spi_controller *acpi_spi_find_controller_by_adev(struct acpi_device *adev)
+struct spi_controller *acpi_spi_find_controller_by_adev(struct acpi_device *adev)
 {
 	struct device *dev;
 
@@ -4533,6 +4531,7 @@ static struct spi_controller *acpi_spi_find_controller_by_adev(struct acpi_devic
 
 	return container_of(dev, struct spi_controller, dev);
 }
+EXPORT_SYMBOL_GPL(acpi_spi_find_controller_by_adev);
 
 static struct spi_device *acpi_spi_find_device_by_adev(struct acpi_device *adev)
 {

include/linux/spi/spi.h

@@ -867,6 +867,7 @@ extern int devm_spi_register_controller(struct device *dev,
 extern void spi_unregister_controller(struct spi_controller *ctlr);
 
 #if IS_ENABLED(CONFIG_ACPI)
+extern struct spi_controller *acpi_spi_find_controller_by_adev(struct acpi_device *adev);
 extern struct spi_device *acpi_spi_device_alloc(struct spi_controller *ctlr,
 						struct acpi_device *adev,
 						int index);