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Date: Tue, 18 Jan 2011 10:35:16 +1300
From: Ryan Mallon <ryan@bluewatersys.com>
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To: Hong Xu <hong.xu@atmel.com>
Subject: Re: [PATCH] MTD: atmel_nand: Add DMA support to access Nandflash
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On 01/17/2011 08:20 PM, Hong Xu wrote:
> Some SAM9 chips have the ability to perform DMA between CPU and SMC controller.
> This patch adds DMA support for SAM9RL, SAM9G45, SSAM9G46,AM9M10, SAM9M11.
> 
> Signed-off-by: Hong Xu <hong.xu@atmel.com>
> ---

One more comment:

> +	if (cpu_has_dma() && use_dma) {
> +		dma_cap_mask_t mask;
> +
> +		dma_cap_zero(mask);
> +		dma_cap_set(DMA_MEMCPY, mask);
> +		host->dma_chan = dma_request_channel(mask, 0, NULL);
> +
> +		if (!host->dma_chan) {
> +			dev_err(host->dev, "Failed to request DMA channel\n");
> +			host->dma_ready = 0;

Because host is kzalloc'ed above, you do not need to set host->dma_ready
to zero here.

~Ryan

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