[PATCH 5.13 097/175] usb: host: ohci-at91: suspend/resume ports after/before OHCI accesses

From: Greg Kroah-Hartman
Date: Tue Aug 10 2021 - 14:00:51 EST


From: Claudiu Beznea <claudiu.beznea@xxxxxxxxxxxxx>

commit 00de6a572f30ee93cad7e0704ec4232e5e72bda8 upstream.

On SAMA7G5 suspending ports will cut the access to OHCI registers and
any subsequent access to them will lead to CPU being blocked trying to
access that memory. Same thing happens on resume: if OHCI memory is
accessed before resuming ports the CPU will block on that access. The
OCHI memory is accessed on suspend/resume though
ohci_suspend()/ohci_resume().

Acked-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Claudiu Beznea <claudiu.beznea@xxxxxxxxxxxxx>
Cc: stable <stable@xxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20210721132905.1970713-1-claudiu.beznea@xxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/usb/host/ohci-at91.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)

--- a/drivers/usb/host/ohci-at91.c
+++ b/drivers/usb/host/ohci-at91.c
@@ -611,8 +611,6 @@ ohci_hcd_at91_drv_suspend(struct device
if (ohci_at91->wakeup)
enable_irq_wake(hcd->irq);

- ohci_at91_port_suspend(ohci_at91->sfr_regmap, 1);
-
ret = ohci_suspend(hcd, ohci_at91->wakeup);
if (ret) {
if (ohci_at91->wakeup)
@@ -632,7 +630,10 @@ ohci_hcd_at91_drv_suspend(struct device
/* flush the writes */
(void) ohci_readl (ohci, &ohci->regs->control);
msleep(1);
+ ohci_at91_port_suspend(ohci_at91->sfr_regmap, 1);
at91_stop_clock(ohci_at91);
+ } else {
+ ohci_at91_port_suspend(ohci_at91->sfr_regmap, 1);
}

return ret;
@@ -644,6 +645,8 @@ ohci_hcd_at91_drv_resume(struct device *
struct usb_hcd *hcd = dev_get_drvdata(dev);
struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd);

+ ohci_at91_port_suspend(ohci_at91->sfr_regmap, 0);
+
if (ohci_at91->wakeup)
disable_irq_wake(hcd->irq);
else
@@ -651,8 +654,6 @@ ohci_hcd_at91_drv_resume(struct device *

ohci_resume(hcd, false);

- ohci_at91_port_suspend(ohci_at91->sfr_regmap, 0);
-
return 0;
}