On 11/09/2015 07:50 AM, Arnd Bergmann wrote:
The dependency was clearly needed, without it it is possible to
build the core i2c driver as a loadable module and the bq27xxx
driver built-in, which results in link errors:

drivers/built-in.o: In function `bq27xxx_battery_i2c_read':
binder.c:(.text+0x360bf0): undefined reference to `i2c_transfer'
binder.c:(.text+0x360c10): undefined reference to `i2c_transfer'
drivers/built-in.o: In function `bq27xxx_battery_init':
binder.c:(.init.text+0xe668): undefined reference to `i2c_register_driver'
drivers/built-in.o: In function `bq27xxx_battery_exit':
binder.c:(.exit.text+0x1a0c): undefined reference to `i2c_del_driver'

Signed-off-by: Arnd Bergmann <a...@arndb.de>
Fixes: 6bd03ce3c12a ("power: bq27xxx_battery: Remove unneeded dependency in 
Kconfig")
---
The bug was originally found and fixed by Xiong Zhou, but Andrew Davis
broke it again by reverting the fix.

I found it today on my ARM randconfig builds.

diff --git a/drivers/power/Kconfig b/drivers/power/Kconfig
index 237d7aa73e8c..9f53fb74ae6f 100644
--- a/drivers/power/Kconfig
+++ b/drivers/power/Kconfig
@@ -159,6 +159,7 @@ config BATTERY_SBS

  config BATTERY_BQ27XXX
        tristate "BQ27xxx battery driver"
+       depends on I2C || I2C=n
        help
          Say Y here to enable support for batteries with BQ27xxx (I2C/HDQ) 
chips.



Nothing enabled by BATTERY_BQ27XXX depends on I2C, this workaround is not
correct as it prevents BATTERY_BQ27XXX from being built-in when I2C is a
module, there is no reason for this limitation.

The undefined references are caused by BATTERY_BQ27XXX being built-in AND
its I2C functionality being enabled (BATTERY_BQ27XXX_I2C) while I2C is a
module. Reorganizing this driver is being discussed anyway, but in the
meantime a more correct fix would be along the lines of:

diff --git a/drivers/power/Kconfig b/drivers/power/Kconfig
index 6de6ec2..d1d32f9 100644
--- a/drivers/power/Kconfig
+++ b/drivers/power/Kconfig
@@ -167,6 +167,7 @@ config BATTERY_BQ27XXX_I2C
        bool "BQ27xxx I2C support"
        depends on BATTERY_BQ27XXX
        depends on I2C
+       depends on !(I2C=m && BATTERY_BQ27XXX=y)
        default y
        help
          Say Y here to enable support for batteries with BQ27xxx (I2C) chips.
--
To unsubscribe from this list: send the line "unsubscribe linux-i2c" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to