On Fri, 10 Oct 2014, Peter Chen wrote:
> @@ -1216,6 +1221,7 @@ static const struct hc_driver ehci_hc_driver = {
> .bus_resume = ehci_bus_resume,
> .relinquish_port = ehci_relinquish_port,
> .port_handed_over = ehci_port_handed_over,
> + .port_power = ehci_port_power,
>
> /*
> * device support
> @@ -1233,6 +1239,8 @@ void ehci_init_driver(struct hc_driver *drv,
> drv->hcd_priv_size += over->extra_priv_size;
> if (over->reset)
> drv->reset = over->reset;
> + if (over->port_power)
> + drv->port_power = over->port_power;
> +int ehci_port_power(struct usb_hcd *hcd, int portnum, bool enable)
> +{
> + struct ehci_hcd *ehci = hcd_to_ehci(hcd);
You might as well pass ehci as the first argument instead of hcd.
> + u32 __iomem *status_reg = &ehci->regs->port_status[portnum];
> + u32 status = ehci_readl(ehci, status_reg);
> +
> + if (enable)
> + ehci_writel(ehci, status | PORT_POWER, status_reg);
> + else
> + ehci_writel(ehci, status & ~PORT_POWER, status_reg);
These writes are wrong. You have to turn off the RWC bits before
writing anything to the status register; otherwise you will
accidentally turn off some bit that should remain on.
> +
> + return 0;
You missed the point of what I said earlier. This routine should not
be a callback, because it should run every time we adjust the port
power. Then _this_ routine should invoke the callback.
Alan Stern
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