[PATCH net v2] mod_devicetable: fix PHY module format

[PATCH net v2] mod_devicetable: fix PHY module format

[Russell King]

When a PHY is probed, if the top bit is set, we end up requesting a
module with the string "mdio:-10101110000000100101000101010001" -
the top bit is printed to a signed -1 value. This leads to the module
not being loaded.

Fix the module format string and the macro generating the values for
it to ensure that we only print unsigned types and the top bit is
always 0/1. We correctly end up with
"mdio:10101110000000100101000101010001".

Fixes: 8626d3b43280 ("phylib: Support phy module autoloading")
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
 include/linux/mod_devicetable.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/linux/mod_devicetable.h b/include/linux/mod_devicetable.h
index 5714fd35a83c..e3596db077dc 100644
--- a/include/linux/mod_devicetable.h
+++ b/include/linux/mod_devicetable.h
@@ -587,9 +587,9 @@ struct platform_device_id {
 #define MDIO_NAME_SIZE		32
 #define MDIO_MODULE_PREFIX	"mdio:"
 
-#define MDIO_ID_FMT "%d%d%d%d%d%d%d%d%d%d%d%d%d%d%d%d%d%d%d%d%d%d%d%d%d%d%d%d%d%d%d%d"
+#define MDIO_ID_FMT "%u%u%u%u%u%u%u%u%u%u%u%u%u%u%u%u%u%u%u%u%u%u%u%u%u%u%u%u%u%u%u%u"
 #define MDIO_ID_ARGS(_id) \
-	(_id)>>31, ((_id)>>30) & 1, ((_id)>>29) & 1, ((_id)>>28) & 1,	\
+	((_id)>>31) & 1, ((_id)>>30) & 1, ((_id)>>29) & 1, ((_id)>>28) & 1, \
 	((_id)>>27) & 1, ((_id)>>26) & 1, ((_id)>>25) & 1, ((_id)>>24) & 1, \
 	((_id)>>23) & 1, ((_id)>>22) & 1, ((_id)>>21) & 1, ((_id)>>20) & 1, \
 	((_id)>>19) & 1, ((_id)>>18) & 1, ((_id)>>17) & 1, ((_id)>>16) & 1, \
-- 
2.20.1

Re: [PATCH net v2] mod_devicetable: fix PHY module format

[Florian Fainelli]

On 12/19/2019 3:24 PM, Russell King wrote:
> When a PHY is probed, if the top bit is set, we end up requesting a
> module with the string "mdio:-10101110000000100101000101010001" -
> the top bit is printed to a signed -1 value. This leads to the module
> not being loaded.
> 
> Fix the module format string and the macro generating the values for
> it to ensure that we only print unsigned types and the top bit is
> always 0/1. We correctly end up with
> "mdio:10101110000000100101000101010001".
> 
> Fixes: 8626d3b43280 ("phylib: Support phy module autoloading")
> Reviewed-by: Andrew Lunn <andrew@lunn.ch>
> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
-- 
Florian

Re: [PATCH net v2] mod_devicetable: fix PHY module format

[David Miller]

From: Russell King <rmk+kernel@armlinux.org.uk>
Date: Thu, 19 Dec 2019 23:24:47 +0000

> When a PHY is probed, if the top bit is set, we end up requesting a
> module with the string "mdio:-10101110000000100101000101010001" -
> the top bit is printed to a signed -1 value. This leads to the module
> not being loaded.
> 
> Fix the module format string and the macro generating the values for
> it to ensure that we only print unsigned types and the top bit is
> always 0/1. We correctly end up with
> "mdio:10101110000000100101000101010001".
> 
> Fixes: 8626d3b43280 ("phylib: Support phy module autoloading")
> Reviewed-by: Andrew Lunn <andrew@lunn.ch>
> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

Applied and queued up for -stable.