[fpc-devel] Problems with fpioctl on ARM debian linux and FPC2.6

[Sven Barth]

On 19.06.2012 20:56, Stefan Fischer wrote:
> after some experiments, tx.. and rx_buf_ptr has to be 64 bits. On fps on arm, the pointer type is translated to 32 Bits.
> Ludo's suggestions to use qword (64Bit) is correct.
>
> Is there a possibility to use pointer type with 64 Bits? How ?
>
>
>
>
> spi_ioc_transfer_t = record
>      tx_buf_ptr,dummytx    : pointer;     (* <------------ 64 Bits              dummytx / dummyrx for spaceing *)
>      rx_buf_ptr,dummyrx 	: pointer;
>      len				: longword;
> 	speed_hz    	: longword;
>      delay_usecs		: word;
>      bits_per_word	: byte;
>      cs_change		: byte;
>      pad				: longword;
>    end;


I wouldn't do that. The kernel could use the part that you labeled as 
"dummy*x". Just simply cast a Pointer to QWord and be happy. As long as 
we don't have a 128-bit system this will work ;) (and C basically does 
the same)

Regards,
Sven