On Mon, Oct 11, 2021 at 09:02:58PM +0800, Yinbo Zhu wrote:
> The usb states of ohci controller include UsbOperational, UsbReset,
> UsbSuspend and UsbResume. Among them, only the UsbOperational state
> supports launching the start of frame for host controller according
> the ohci protocol spec, but in S3 and S4 (suspend to memory/suspend
> to disk) press test procedure, it may happen that the start of
> frame was launched in other usb states and cause ohci works failed,
> that the phenomenon was hc will allways reproduce the SoF interrupt
> and consider that hc doesn't deal with the ed/td/done list in non-
> UsbOperational, and this patch was to add check for host controller
> functional states and if it is not UsbOperational state that need
> set INTR_SF in intrdisable register to ensure SOF Token generation
> was been disabled so that it can fix ohci SoF abnormally interrupt.
I do not understand this change. What commit is this fixing? What
devices today do not work with the code as-is?
>
> Signed-off-by: Yinbo Zhu <zhuyinbo@xxxxxxxxxxx>
> ---
> Change in v4:
> Rework the commit log information.
> Remove the extra unnecessary blank line.
>
>
> drivers/usb/host/ohci-hcd.c | 11 ++++++++---
> 1 file changed, 8 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/usb/host/ohci-hcd.c b/drivers/usb/host/ohci-hcd.c
> index 1f5e693..4fd59fa 100644
> --- a/drivers/usb/host/ohci-hcd.c
> +++ b/drivers/usb/host/ohci-hcd.c
> @@ -879,7 +879,7 @@ static irqreturn_t ohci_irq (struct usb_hcd *hcd)
> {
> struct ohci_hcd *ohci = hcd_to_ohci (hcd);
> struct ohci_regs __iomem *regs = ohci->regs;
> - int ints;
> + int ints, ctl;
New line for a new variable please.
>
> /* Read interrupt status (and flush pending writes). We ignore the
> * optimization of checking the LSB of hcca->done_head; it doesn't
> @@ -969,9 +969,14 @@ static irqreturn_t ohci_irq (struct usb_hcd *hcd)
> * when there's still unlinking to be done (next frame).
> */
> ohci_work(ohci);
> - if ((ints & OHCI_INTR_SF) != 0 && !ohci->ed_rm_list
> - && ohci->rh_state == OHCI_RH_RUNNING)
> +
> + ctl = ohci_readl(ohci, ®s->control);
> + if (((ints & OHCI_INTR_SF) != 0 && !ohci->ed_rm_list
> + && ohci->rh_state == OHCI_RH_RUNNING) ||
> + ((ctl & OHCI_CTRL_HCFS) != OHCI_USB_OPER)) {
> ohci_writel (ohci, OHCI_INTR_SF, ®s->intrdisable);
> + (void)ohci_readl(ohci, ®s->intrdisable);
No need for (void).
thanks,
greg k-h
