[PATCH v3 2/3] ACPI: bus: Constify acpi_dma_supported() helper function

[Andy Shevchenko <andriy.shevchenko@linux.intel.com>]

Constify arguments to acpi_dma_supported(). The function doesn't need
to change the content of the passed argument and when it's const it
allows to supply the result of other functions that may return a pointer
to a constant object.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
v3: new patch
 drivers/acpi/scan.c     | 2 +-
 include/acpi/acpi_bus.h | 2 +-
 include/linux/acpi.h    | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index a2df7bcf4d07..5040ce3c3ed1 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -1405,7 +1405,7 @@ void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
  *
  * Return false if DMA is not supported. Otherwise, return true
  */
-bool acpi_dma_supported(struct acpi_device *adev)
+bool acpi_dma_supported(const struct acpi_device *adev)
 {
 	if (!adev)
 		return false;
diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index 3a82faac5767..2fbd2c2e0568 100644
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -586,7 +586,7 @@ struct acpi_pci_root {
 
 /* helper */
 
-bool acpi_dma_supported(struct acpi_device *adev);
+bool acpi_dma_supported(const struct acpi_device *adev);
 enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev);
 int acpi_dma_get_range(struct device *dev, u64 *dma_addr, u64 *offset,
 		       u64 *size);
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 40657f220f8b..97f1c5588b5a 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -911,7 +911,7 @@ acpi_create_platform_device(struct acpi_device *adev,
 	return NULL;
 }
 
-static inline bool acpi_dma_supported(struct acpi_device *adev)
+static inline bool acpi_dma_supported(const struct acpi_device *adev)
 {
 	return false;
 }
-- 
2.30.2