Re: [PATCH v3 2/3] usb: xhci: This reworks ff8cbf250b448aac35589f6075082c3fcad8a8fe

From: Alan Stern
Date: Wed Nov 05 2014 - 16:24:09 EST


On Wed, 5 Nov 2014, Lu Baolu wrote:

> xhci: clear root port wake on bits if controller isn't allowed to do wakeup
>
> When system is being suspended, if host device is not allowed to do wakeup,
> xhci_suspend() needs to clear all root port wake on bits. Otherwise, some
> platforms may generate spurious wakeup, even if PCI PME# is disabled.
>
> Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
> Suggested-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>

This looks pretty good now.

> +static void xhci_disable_port_wake_on_bits(struct xhci_hcd *xhci)
> +{
> + int port_index;
> + __le32 __iomem **port_array;
> + unsigned long flags;
> + u32 t1, t2;
> +
> + spin_lock_irqsave(&xhci->lock, flags);
> +
> + /* disble usb3 ports Wake bits*/
> + port_index = xhci->num_usb3_ports;
> + port_array = xhci->usb3_ports;
> + while (port_index--) {
> + t1 = readl(port_array[port_index]);
> + t2 = xhci_port_state_to_neutral(t1);
> + t2 &= ~PORT_WAKE_BITS;
> + t1 = xhci_port_state_to_neutral(t1);
> + if (t1 != t2)
> + writel(t2, port_array[port_index]);

Why not just do:

t1 = readl(port_array[port_index]);
t1 = xhci_port_state_to_neutral(t1);
t2 = t1 & ~PORT_WAKE_BITS;
if (t1 != t2) ...

Apart from that minor point,

Acked-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>

Alan Stern

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/