Re: [PATCH] mod/file2alias: make modalias generation safe for cross compiling

[Andreas Schwab <schwab@linux-m68k.org>]

Geert Uytterhoeven <geert@linux-m68k.org> writes:

> 	Hi Andreas,
>
> On Mon, 25 Jun 2012, Andreas Schwab wrote:
>> --- /dev/null
>> +++ b/scripts/mod/devicetable-offsets.c
>> @@ -0,0 +1,171 @@
>> +#include <linux/kbuild.h>
>> +#include <linux/mod_devicetable.h>
>> +
>> +#define DEVID(devid) DEFINE(SIZE_##devid, sizeof(struct devid))
>> +#define DEVID_FIELD(devid, field) \
>> +	DEFINE(OFF_##devid##_##field, offsetof(struct devid, field))
>> +
>> +int main(void)
>> +{
>> +	DEVID(usb_device_id);
>> +	DEVID_FIELD(usb_device_id, match_flags);
>> +	DEVID_FIELD(usb_device_id, idVendor);
>> +	DEVID_FIELD(usb_device_id, idProduct);
>> +	DEVID_FIELD(usb_device_id, bcdDevice_lo);
>> +	DEVID_FIELD(usb_device_id, bcdDevice_hi);
>> +	DEVID_FIELD(usb_device_id, bDeviceClass);
>> +	DEVID_FIELD(usb_device_id, bDeviceSubClass);
>> +	DEVID_FIELD(usb_device_id, bDeviceProtocol);
>> +	DEVID_FIELD(usb_device_id, bInterfaceClass);
>> +	DEVID_FIELD(usb_device_id, bInterfaceSubClass);
>> +	DEVID_FIELD(usb_device_id, bInterfaceProtocol);
>
> These are all duplicates of the structures in <linux/mod_devicetable.h>.
> Can't you get rid of the duplication by putting e.g. the following
> in <linux/mod_devicetable.h>:
>
>     DEVID_START(usb_device_id);
>     DEVID_FIELD(usb_device_id, __u16, match_flags);
>     DEVID_FIELD(usb_device_id, __u16, idVendor);
>     DEVID_FIELD(usb_device_id, __u16, idProduct);
>     DEVID_FIELD(usb_device_id, __u16, bcdDevice_lo);
>     DEVID_FIELD(usb_device_id, __u16, bcdDevice_hi);
>     DEVID_FIELD(usb_device_id, __u8, bDeviceClass);
>     DEVID_FIELD(usb_device_id, __u8, bDeviceSubClass);
>     DEVID_FIELD(usb_device_id, __u8, bDeviceProtocol);
>     DEVID_FIELD(usb_device_id, __u8, bInterfaceClass);
>     DEVID_FIELD(usb_device_id, __u8, bInterfaceSubClass);
>     DEVID_FIELD(usb_device_id, __u8, bInterfaceProtocol);
>     DEVID_END();
>
> and redefining the DEVID_*() macros depending on
>   1. __KERNEL__, to generate the C struct definitions for kernel builds,
>   2. first inclusion by devicetable-offsets.c, also to generate C struct
>      definitions,
>   3. second inclusion by devicetable-offsets.c, to generate the sizes and
>      offset definitions for modalias?

That requires some reorganisation of the struct pnp_card_device_id which
has a somewhat complicated structure (which also accounts for the
ugliest part of the patch).

Andreas.

-- 
Andreas Schwab, schwab@linux-m68k.org
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