Subject: Re: [PATCH 2.6.10-rc2] ppc32: Add usb support to IBM stb04xxx platforms including Redwood5

From: Eugene Surovegin <[email-masked]>
Date: Wed, 30 Mar 2005 17:07:47 -0800

On Wed, Mar 30, 2005 at 05:05:21PM -0700, Dale Farnsworth wrote:

[snip]

> +/* Power up the USB subsection */
> +static int enable_usb(struct platform_device *pdev)
> +{
> +	u32 mask;
> +
> +	mask = 1 << (31 - USB0_IRQ);
> +	mtdcr(DCRN_UIC_PR(UIC0), mfdcr(DCRN_UIC_PR(UIC0)) | mask);
> +	mtdcr(DCRN_UIC_TR(UIC0), mfdcr(DCRN_UIC_TR(UIC0)) & ~mask);
> +	return 0;
> +}
> +
> +/* Power down the USB subsection */
> +static void disable_usb(struct platform_device *pdev)
> +{
> +	u32 mask;
> +
> +	mask = 1 << (31 - USB0_IRQ);
> +	mtdcr(DCRN_UIC_PR(UIC0), mfdcr(DCRN_UIC_PR(UIC0)) & ~mask);
> +	mtdcr(DCRN_UIC_TR(UIC0), mfdcr(DCRN_UIC_TR(UIC0)) | mask);
> +}

Dale, I'm curious, what's going on here :) ?.

How changing polarity and triggering setting could power-down USB 
unit? Some STB funkiness?

--
Eugene