diff mbox series

[1/2] of: Support using 'mask' in making device bus id

Message ID 20211109164650.2233507-2-robh@kernel.org (mailing list archive)
State Not Applicable, archived
Headers show
Series Fix Arm Ltd board node name collisions | expand

Commit Message

Rob Herring (Arm) Nov. 9, 2021, 4:46 p.m. UTC
Commit 25b892b583cc ("ARM: dts: arm: Update register-bit-led nodes
'reg' and node names") added a 'reg' property to nodes. This change has
the side effect of changing how the kernel generates the device name.
The assumption was a translatable 'reg' address is unique. However, in
the case of the register-bit-led binding (and a few others) that is not
the case. The 'mask' property must also be used in this case to make a
unique device name.

Fixes: 25b892b583cc ("ARM: dts: arm: Update register-bit-led nodes 'reg' and node names")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Cc: stable@vger.kernel.org
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Rob Herring <robh@kernel.org>
---
This should be applied to stable to minimize DT ABI breakage.
---
 drivers/of/platform.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

Comments

Linus Walleij Nov. 9, 2021, 10:20 p.m. UTC | #1
On Tue, Nov 9, 2021 at 5:46 PM Rob Herring <robh@kernel.org> wrote:

> Commit 25b892b583cc ("ARM: dts: arm: Update register-bit-led nodes
> 'reg' and node names") added a 'reg' property to nodes. This change has
> the side effect of changing how the kernel generates the device name.
> The assumption was a translatable 'reg' address is unique. However, in
> the case of the register-bit-led binding (and a few others) that is not
> the case. The 'mask' property must also be used in this case to make a
> unique device name.
>
> Fixes: 25b892b583cc ("ARM: dts: arm: Update register-bit-led nodes 'reg' and node names")
> Reported-by: Guenter Roeck <linux@roeck-us.net>
> Cc: stable@vger.kernel.org
> Cc: Frank Rowand <frowand.list@gmail.com>
> Cc: Linus Walleij <linus.walleij@linaro.org>
> Signed-off-by: Rob Herring <robh@kernel.org>

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

Yours,
Linus Walleij
diff mbox series

Patch

diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index 07813fb1ef37..b3faf89744aa 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -76,6 +76,7 @@  static void of_device_make_bus_id(struct device *dev)
 	struct device_node *node = dev->of_node;
 	const __be32 *reg;
 	u64 addr;
+	u32 mask;
 
 	/* Construct the name, using parent nodes if necessary to ensure uniqueness */
 	while (node->parent) {
@@ -85,8 +86,13 @@  static void of_device_make_bus_id(struct device *dev)
 		 */
 		reg = of_get_property(node, "reg", NULL);
 		if (reg && (addr = of_translate_address(node, reg)) != OF_BAD_ADDR) {
-			dev_set_name(dev, dev_name(dev) ? "%llx.%pOFn:%s" : "%llx.%pOFn",
-				     addr, node, dev_name(dev));
+			if (!of_property_read_u32(node, "mask", &mask))
+				dev_set_name(dev, dev_name(dev) ? "%llx.%x.%pOFn:%s" : "%llx.%x.%pOFn",
+					     addr, ffs(mask) - 1, node, dev_name(dev));
+
+			else
+				dev_set_name(dev, dev_name(dev) ? "%llx.%pOFn:%s" : "%llx.%pOFn",
+					     addr, node, dev_name(dev));
 			return;
 		}