diff mbox series

[v2,1/2] amba: bus: balance firmware node reference counting

Message ID 20231002132635.2595382-1-andriy.shevchenko@linux.intel.com
State Changes Requested
Headers show
Series [v2,1/2] amba: bus: balance firmware node reference counting | expand

Checks

Context Check Description
robh/checkpatch success
robh/patch-applied fail build log

Commit Message

'Andy Shevchenko' Oct. 2, 2023, 1:26 p.m. UTC
Currently the ACPI code doesn't bump the reference count of
the firmware node, while OF counter part does. Not that it's
a problem right now, since ACPI doesn't really use the reference
counting for firmware nodes, it still makes sense to make code
robust against any changes done there. For this,
 - switch ACPI case to use device_set_node() to be unified with OF
 - move reference counting to amba_device_add()
 - switch to use firmware nodes instead of OF ones

In the result we will have reference counting done in the same module
for all callers independently on the nature of firmware node behind.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---

v2: fixed compilation error (LKP), all dependencies are in v6.6-rcX (Rob)

 drivers/acpi/arm64/amba.c | 2 +-
 drivers/amba/bus.c        | 5 ++++-
 drivers/of/platform.c     | 2 +-
 3 files changed, 6 insertions(+), 3 deletions(-)

Comments

Rob Herring Oct. 2, 2023, 5:38 p.m. UTC | #1
On Mon, Oct 2, 2023 at 8:32 AM Andy Shevchenko
<andriy.shevchenko@linux.intel.com> wrote:
>
> There is no architecture specific code in the implementation of
> AMBA bus, let's enable compile testing for it.
>
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
>
> v2: new patch to make it easier to compile test on non-ARM
>
>  drivers/amba/Kconfig | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/amba/Kconfig b/drivers/amba/Kconfig
> index fb6c7e0b4cce..9ff4638550c8 100644
> --- a/drivers/amba/Kconfig
> +++ b/drivers/amba/Kconfig
> @@ -1,6 +1,6 @@
>  # SPDX-License-Identifier: GPL-2.0
>  config ARM_AMBA
> -       bool
> +       bool "AMBA bus support" || if COMPILE_TEST

Other than not compile testing a compile test enabling patch, it's
really "Arm (AMBA) Primecell Device bus". Despite the naming, AMBA
encompasses lots of Arm defined buses, but what this bus type is is
just peripherals which have the Primecell device ID registers.

Rob
diff mbox series

Patch

diff --git a/drivers/acpi/arm64/amba.c b/drivers/acpi/arm64/amba.c
index 60be8ee1dbdc..171b5c2c7edd 100644
--- a/drivers/acpi/arm64/amba.c
+++ b/drivers/acpi/arm64/amba.c
@@ -101,7 +101,7 @@  static int amba_handler_attach(struct acpi_device *adev,
 	if (parent)
 		dev->dev.parent = acpi_get_first_physical_node(parent);
 
-	ACPI_COMPANION_SET(&dev->dev, adev);
+	device_set_node(&dev->dev, acpi_fwnode_handle(adev));
 
 	ret = amba_device_add(dev, &iomem_resource);
 	if (ret) {
diff --git a/drivers/amba/bus.c b/drivers/amba/bus.c
index 09e72967b8ab..a24c152bfaac 100644
--- a/drivers/amba/bus.c
+++ b/drivers/amba/bus.c
@@ -18,6 +18,7 @@ 
 #include <linux/limits.h>
 #include <linux/clk/clk-conf.h>
 #include <linux/platform_device.h>
+#include <linux/property.h>
 #include <linux/reset.h>
 #include <linux/of_irq.h>
 #include <linux/of_device.h>
@@ -528,7 +529,7 @@  static void amba_device_release(struct device *dev)
 {
 	struct amba_device *d = to_amba_device(dev);
 
-	of_node_put(d->dev.of_node);
+	fwnode_handle_put(dev_fwnode(&d->dev));
 	if (d->res.parent)
 		release_resource(&d->res);
 	mutex_destroy(&d->periphid_lock);
@@ -548,6 +549,8 @@  int amba_device_add(struct amba_device *dev, struct resource *parent)
 {
 	int ret;
 
+	fwnode_handle_get(dev_fwnode(&dev->dev));
+
 	ret = request_resource(parent, &dev->res);
 	if (ret)
 		return ret;
diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index f235ab55b91e..126d265aa7d8 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -273,7 +273,7 @@  static struct amba_device *of_amba_device_create(struct device_node *node,
 	dev->dev.dma_mask = &dev->dev.coherent_dma_mask;
 
 	/* setup generic device info */
-	device_set_node(&dev->dev, of_fwnode_handle(of_node_get(node)));
+	device_set_node(&dev->dev, of_fwnode_handle(node));
 	dev->dev.parent = parent ? : &platform_bus;
 	dev->dev.platform_data = platform_data;
 	if (bus_id)