Re: [PATCH] ethernet: atheros: Add nss-gmac driver

[Stephen Hemminger <stephen@networkplumber.org>]

On Thu,  8 Jan 2015 14:03:46 -0800
Stephen Wang <wstephen@codeaurora.org> wrote:

> +static int32_t nss_gmac_setup_tx_desc_queue(struct nss_gmac_dev *gmacdev,
> +						struct device *dev,
> +						uint32_t no_of_desc,
> +						uint32_t desc_mode)
> +{
> +	int32_t i;
> +	struct dma_desc *first_desc = NULL;
> +	dma_addr_t dma_addr;
> +
> +	gmacdev->tx_desc_count = 0;
> +
> +	BUG_ON(desc_mode != RINGMODE);
> +	BUG_ON((no_of_desc & (no_of_desc - 1)) != 0);
> +
> +	netdev_dbg(gmacdev->netdev, "Total size of memory required for Tx Descriptors in Ring Mode = 0x%08x"
> +			, (uint32_t) ((sizeof(struct dma_desc) * no_of_desc)));
> +
> +	first_desc = dma_alloc_coherent(dev, sizeof(struct dma_desc) * no_of_desc
> +					, &dma_addr, GFP_KERNEL);
> +	if (first_desc == NULL) {

In a lot of places you first initialize a variable then assign it 5 lines
later to it's initial value.  Get rid of the first initialization.