Re: [PATCH 2/2] usb: cdns3: Optimize DMA request buffer allocation

[Christoph Hellwig]

On Tue, Mar 09, 2021 at 06:19:40AM +0100, Sanket Parmar wrote:
> dma_alloc_coherent() might fail on the platform with a small DMA region.
> 
> To avoid such failure in cdns3_prepare_aligned_request_buf(),
> dma_alloc_coherent() is replaced with kmalloc and dma_map API to
> allocate aligned request buffer of dynamic length.

dma_alloc_noncoherent is the proper API instead of using kmalloc, which
can lead to unaddressable memory that might require bounce buffering.