On Wednesday 07 October 2015 20:42:39 H. Nikolaus Schaller wrote:
> Explicitly call request_module() in the wrapper so that the
> bq27x00_battery driver is loded on demand, when compiled as module.
> 
> Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
> ---
>  drivers/w1/slaves/w1_bq27000.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/w1/slaves/w1_bq27000.c
> b/drivers/w1/slaves/w1_bq27000.c index caafb17..745bd6e 100644
> --- a/drivers/w1/slaves/w1_bq27000.c
> +++ b/drivers/w1/slaves/w1_bq27000.c
> @@ -49,6 +49,8 @@ static int w1_bq27000_add_slave(struct w1_slave
> *sl) int ret;
>  	struct platform_device *pdev;
> 
> +	request_module("bq27x00_battery");  /* load as module if needed */
> +
>  	pdev = platform_device_alloc("bq27000-battery", -1);
>  	if (!pdev) {
>  		ret = -ENOMEM;

Hi! Function platform_device_alloc would allocate kernel device and it 
should also load appropriate kernel driver (via platform:bq27000-battery 
alias). If that does not work, problem is somewhere else. Maybe depmod 
is not properly generated? Or bq27x00_batter.ko modules does not contain 
needed alias?

Adding request_module() here is not proper solution. Real problem is 
somewhere else... Anyway there is series of patches for bq27x00_battery 
which should cleanup some problems, so maybe they also fix your problem.

-- 
Pali Rohár
pali.rohar@gmail.com