The xHCI 1.0 spec errata released on June 13, 2011, changes the ordering that the xHCI registers are saved and restored in. It moves the interrupt pending (IMAN) and interrupt control (IMOD) registers to be saved and restored last. I believe that's because the host controller may attempt to fetch the event ring table when interrupts are re-enabled. Therefore we need to restore the event ring registers before we re-enable interrupts. This should be backported to kernels as old as 2.6.37, that contain the commit 5535b1d5f8885695c6ded783c692e3c0d0eda8ca "USB: xHCI: PCI power management implementation" Signed-off-by: Sarah Sharp <sarah.a.sharp@xxxxxxxxxxxxxxx> Tested-by: Elric Fu <elricfu1@xxxxxxxxx> Cc: Andiry Xu <andiry.xu@xxxxxxx> Cc: stable@xxxxxxxxxxxxxxx --- drivers/usb/host/xhci.c | 8 ++++---- 1 files changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index d2222dc..36641a7 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -667,11 +667,11 @@ static void xhci_save_registers(struct xhci_hcd *xhci) xhci->s3.dev_nt = xhci_readl(xhci, &xhci->op_regs->dev_notification); xhci->s3.dcbaa_ptr = xhci_read_64(xhci, &xhci->op_regs->dcbaa_ptr); xhci->s3.config_reg = xhci_readl(xhci, &xhci->op_regs->config_reg); - xhci->s3.irq_pending = xhci_readl(xhci, &xhci->ir_set->irq_pending); - xhci->s3.irq_control = xhci_readl(xhci, &xhci->ir_set->irq_control); xhci->s3.erst_size = xhci_readl(xhci, &xhci->ir_set->erst_size); xhci->s3.erst_base = xhci_read_64(xhci, &xhci->ir_set->erst_base); xhci->s3.erst_dequeue = xhci_read_64(xhci, &xhci->ir_set->erst_dequeue); + xhci->s3.irq_pending = xhci_readl(xhci, &xhci->ir_set->irq_pending); + xhci->s3.irq_control = xhci_readl(xhci, &xhci->ir_set->irq_control); } static void xhci_restore_registers(struct xhci_hcd *xhci) @@ -680,11 +680,11 @@ static void xhci_restore_registers(struct xhci_hcd *xhci) xhci_writel(xhci, xhci->s3.dev_nt, &xhci->op_regs->dev_notification); xhci_write_64(xhci, xhci->s3.dcbaa_ptr, &xhci->op_regs->dcbaa_ptr); xhci_writel(xhci, xhci->s3.config_reg, &xhci->op_regs->config_reg); - xhci_writel(xhci, xhci->s3.irq_pending, &xhci->ir_set->irq_pending); - xhci_writel(xhci, xhci->s3.irq_control, &xhci->ir_set->irq_control); xhci_writel(xhci, xhci->s3.erst_size, &xhci->ir_set->erst_size); xhci_write_64(xhci, xhci->s3.erst_base, &xhci->ir_set->erst_base); xhci_write_64(xhci, xhci->s3.erst_dequeue, &xhci->ir_set->erst_dequeue); + xhci_writel(xhci, xhci->s3.irq_pending, &xhci->ir_set->irq_pending); + xhci_writel(xhci, xhci->s3.irq_control, &xhci->ir_set->irq_control); } static void xhci_set_cmd_ring_deq(struct xhci_hcd *xhci) -- 1.7.9 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
