[alsa-devel] [PATCH v3] dbri: Fix compiler warning

[tndave]

On 11/25/2016 08:54 AM, David Miller wrote:
> From: Takashi Iwai <tiwai at suse.de>
> Date: Fri, 25 Nov 2016 10:30:48 +0100
>
>> On Thu, 24 Nov 2016 21:35:16 +0100,
>> Tushar Dave wrote:
>>>
>>> dbri uses 'u32' for dma handle while invoking kernel DMA APIs,
>>> instead of using dma_addr_t. This hasn't caused any 'incompatible
>>> pointer type' warning on SPARC because until now dma_addr_t is of
>>> type u32. However, recent changes in SPARC ATU (iommu) enabled 64bit
>>> DMA and therefore dma_addr_t became of type u64. This makes
>>> 'incompatible pointer type' warnings inevitable.
>>>
>>> e.g.
>>> sound/sparc/dbri.c: In function ‘snd_dbri_create’:
>>> sound/sparc/dbri.c:2538: warning: passing argument 3 of ‘dma_zalloc_coherent’ from incompatible pointer type
>>> ./include/linux/dma-mapping.h:608: note: expected ‘dma_addr_t *’ but argument is of type ‘u32 *’
>>>
>>> For the record, dbri(sbus) driver never executes on sun4v. Therefore
>>> even though 64bit DMA is enabled on SPARC, dbri continues to use
>>> legacy iommu that guarantees DMA address is always in 32bit range.
>>>
>>> This patch resolves above compiler warning.
>>>
>>> Signed-off-by: Tushar Dave <tushar.n.dave at oracle.com>
>>> Reviewed-by: thomas tai <thomas.tai at oracle.com>
>>> ---
>>> v2->v3:
>>> - Use %pad to print dma_addr_t. Comment by Takashi Iwai.
>>
>> Applied now.  Thanks!
>
> This patch is absolutely not appropriate for your tree Takashi.
>
> It's for the sparc tree because that's where the dma_addr_t
> type was changed from 32-bit to 64-bit on sparc64, which is
> what caused this build warning.
>
> Dave, please only send sparc specific driver patches to
> sparclinux at vger.kernel.org in the future so we can avoid
> this kind of problem.  The whole handling of the dma_addr_t
> type change on sparc64 has been a real mess, quite honestly.
I got your point. I will keep it in mind in future submission.

Thanks.

-Tushar

>