Re: [RFC] ux500 dma & short transfers on MUSB

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On Fri, Jul 19, 2013 at 2:51 PM, Sebastian Andrzej Siewior
<bigeasy@xxxxxxxxxxxxx> wrote:
> On 07/19/2013 11:16 AM, Rajaram R wrote:
>> That was work in progress. You may wish to look at this patch
>> http://permalink.gmane.org/gmane.linux.usb.general/79858
>>
>> If a device sends 513 bytes to a musb device. 512 bytes will be
>> received in DMA mode and 1 byte in FIFO mode.
>>
>> FIFO will always handle data < 512.
>
> Okay. Let me rephrase this: Lets say there is a read request for 4096
> bytes and your maxpacket is 512 and total of 4096 bytes will be sent by
> the device. How many interrupts / read requests will there be?
> 8 like every maxpacket size or is it possible to stuff more data and
> transfer 4096 in one go?

Not 100% sure, but as i remember it will be 8 times in the present
driver (atleast host mode). But yes we can do 4096 at a time.

>
>>>> Cheers
>>>
> Sebastian
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