[PATCH v2] dmaengine: add CSR SiRFprimaII DMAC driver
Barry Song
21cnbao at gmail.com
Tue Sep 20 01:25:22 EDT 2011
2011/9/20 Jassi Brar <jaswinder.singh at linaro.org>:
> On 19 September 2011 16:55, Barry Song <21cnbao at gmail.com> wrote:
>> 2011/9/19 Vinod Koul <vinod.koul at intel.com>:
>>> On Mon, 2011-09-19 at 09:56 +0000, Barry Song wrote:
>>>> > > > Not sure why you support this, there seem to be no DMA_SLAVE
>>>> support in
>>>> > > > this version ate least
>>>> > >
>>>> > > Not. I support dma_slave. But I have no prep_slave_sg function
>>>> since I can
>>>> > use the gen xfer to replace it.
>>>> > Yes thats okay...
>>>> >
>>>> > Then I have questions on genxfer function...
>>>> > where are you copying either src or dstn_start address, you seem to
>>>> > completely ignore them?
>>>>
>>>> Since I only support memory->device or device ->memory, and channel
>>>> number is fixed to every device. Then I actually don't care device
>>>> address at all. Either src or dst is fixed to the device's address.
>>> peripheral address can be fixed, not the memory, where do you copy the
>>> memory address?
>>
>> +static int sirfsoc_dma_slave_config(struct sirfsoc_dma_chan *schan,
>> + struct dma_slave_config *config)
>> +{
>> + u32 addr, direction;
>> + unsigned long flags;
>> +
>> + switch (config->direction) {
>> + case DMA_FROM_DEVICE:
>> + direction = 0;
>> + addr = config->dst_addr;
>> + break;
>> +
>> + case DMA_TO_DEVICE:
>> + direction = 1;
>> + addr = config->src_addr;
>> + break;
>> +
>> + default:
>> + return -EINVAL;
>> + }
>> + ...
> I repeat
> {
> Pass addresses using dmaxfer_template.src_start and dmaxfer_template.dst_start
> instead of dma_slave_config.dst_addr and dma_slave_config.src_addr
> }
agree.
-barry
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