Re: [PATCH net-next] iwmc3200bt: Add iwmc3200 bluetooth driver

[David Vrabel <david.vrabel@csr.com>]

Tomas Winkler wrote:
> Add Intel Wireless MultiCom 3200 SDIO BT driver
> IWMC3200 is 4Wireless Com CHIP (GPS/BT/WiFi/WiMAX).
> wmc3200bt is derived from btsdio driver

Can you list the hardware differences between this chip and the standard?

> +	unsigned char tx_buf[2048];
> +	unsigned char rx_buf[2048];

I don't think these buffers are cache line aligned so can't be used for DMA.

> +		/* in IWMC_BT we need to read the transfer length
> +		 * before interrupt clearing */
> +		val1 = sdio_readb(data->func, REG_H2D_COUNT_L, &err);
> +		IBT_DBG(data->func, "%s to read len1,"
> +			" reg_addr=%x ret=%d val=%x\n",
> +			err ? "Failed" : "Succeeded",
> +			REG_H2D_COUNT_L, err, err ? 0xff : val1);
> +		if (err == 0) {
> +			val2 = sdio_readb(data->func, REG_H2D_COUNT_H, &err);
> +			IBT_DBG(data->func, "%s to read len2,"
> +				" reg_addr=%x ret=%d val=%x\n",
> +				err ? "Failed" : "Succeeded",
> +				REG_H2D_COUNT_H, err, err ? 0xff : val2);

Wow.  Intel really messed up the hardware here.  An extra two SDIO
commands per packet?  I guess no one was thinking of performance...

David
-- 
David Vrabel, Senior Software Engineer, Drivers
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