[PATCH] i3c: fix module_i3c_i2c_driver() with I3C=n
From: Arnd Bergmann
Date: Fri Jul 25 2025 - 05:06:24 EST
From: Arnd Bergmann <arnd@xxxxxxxx>
When CONFIG_I3C is disabled and the i3c_i2c_driver_register() happens
to not be inlined, any driver calling it still references the i3c_driver
instance, which then causes a link failure:
x86_64-linux-ld: drivers/hwmon/lm75.o: in function `lm75_i3c_reg_read':
lm75.c:(.text+0xc61): undefined reference to `i3cdev_to_dev'
x86_64-linux-ld: lm75.c:(.text+0xd25): undefined reference to `i3c_device_do_priv_xfers'
x86_64-linux-ld: lm75.c:(.text+0xdd8): undefined reference to `i3c_device_do_priv_xfers'
This issue was part of the original i3c code, but only now caused problems
when i3c support got added to lm75.
Change the 'inline' annotations in the header to '__always_inline' to
ensure that the dead-code-elimination pass in the compiler can optimize
it out as intended.
Fixes: 6071d10413ff ("hwmon: (lm75) add I3C support for P3T1755")
Fixes: 3a379bbcea0a ("i3c: Add core I3C infrastructure")
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
include/linux/i3c/device.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/include/linux/i3c/device.h b/include/linux/i3c/device.h
index b674f64d0822..7f136de4b73e 100644
--- a/include/linux/i3c/device.h
+++ b/include/linux/i3c/device.h
@@ -245,7 +245,7 @@ void i3c_driver_unregister(struct i3c_driver *drv);
*
* Return: 0 if both registrations succeeds, a negative error code otherwise.
*/
-static inline int i3c_i2c_driver_register(struct i3c_driver *i3cdrv,
+static __always_inline int i3c_i2c_driver_register(struct i3c_driver *i3cdrv,
struct i2c_driver *i2cdrv)
{
int ret;
@@ -270,7 +270,7 @@ static inline int i3c_i2c_driver_register(struct i3c_driver *i3cdrv,
* Note that when CONFIG_I3C is not enabled, this function only unregisters the
* @i2cdrv.
*/
-static inline void i3c_i2c_driver_unregister(struct i3c_driver *i3cdrv,
+static __always_inline void i3c_i2c_driver_unregister(struct i3c_driver *i3cdrv,
struct i2c_driver *i2cdrv)
{
if (IS_ENABLED(CONFIG_I3C))
--
2.39.5