patch "usb: host: ohci-at91: suspend/resume ports after/before OHCI accesses" added to usb-linus

This is a note to let you know that I've just added the patch titled

usb: host: ohci-at91: suspend/resume ports after/before OHCI accesses

to my usb git tree which can be found at
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git
in the usb-linus branch.

The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.)

The patch will hopefully also be merged in Linus's tree for the next -rc kernel release.

If you have any questions about this process, please let me know.

From 00de6a572f30ee93cad7e0704ec4232e5e72bda8 Mon Sep 17 00:00:00 2001
From: Claudiu Beznea <[email protected]>
Date: Wed, 21 Jul 2021 16:29:05 +0300
Subject: usb: host: ohci-at91: suspend/resume ports after/before OHCI accesses

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().

---
 drivers/usb/host/ohci-at91.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

index 9bbd7ddd0003..a24aea3d2759 100644
@@ -611,8 +611,6 @@ ohci_hcd_at91_drv_suspend(struct device *dev)
 	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 *dev)
 		/* 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 *dev)
 	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 *dev)
 
 	ohci_resume(hcd, false);
 
-	ohci_at91_port_suspend(ohci_at91->sfr_regmap, 0);
-
 	return 0;
 }
 

2.32.0