[PATCH] usb: gadget: atmel_usba_udc: Expose correct device speed

Boris Brezillon boris.brezillon at free-electrons.com
Mon Nov 16 10:22:08 PST 2015

From: Douglas Gilbert <dgilbert at interlog.com>

Following changes that appeared in lk 4.0.0, the gadget udc driver for
some ARM based Atmel SoCs (e.g. at91sam9x5 and sama5d3 families)
incorrectly deduced full-speed USB link speed even when the hardware
had negotiated a high-speed link. The fix is to make sure that the
UDPHS Interrupt Enable Register value does not mask the SPEED bit
in the Interrupt Status Register.

For a mass storage gadget this problem lead to failures when the host
had a USB 3 port with the xhci_hcd driver. If the host was a USB 2
port using the ehci_hcd driver then the mass storage gadget worked
(but probably at a lower speed than it should have).

Signed-of-by: Douglas Gilbert <dgilbert at interlog.com>
Reviewed-by: Boris Brezillon <boris.brezillon at free-electrons.com>
Cc: <stable at vger.kernel.org> #4.0+
Fixes: 9870d895ad87 ("usb: atmel_usba_udc: Mask status with enabled irqs")
 drivers/usb/gadget/udc/atmel_usba_udc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/gadget/udc/atmel_usba_udc.c b/drivers/usb/gadget/udc/atmel_usba_udc.c
index f0f2b06..f92f5af 100644
--- a/drivers/usb/gadget/udc/atmel_usba_udc.c
+++ b/drivers/usb/gadget/udc/atmel_usba_udc.c
@@ -1633,7 +1633,7 @@ static irqreturn_t usba_udc_irq(int irq, void *devid)
 	int_enb = usba_int_enb_get(udc);
-	status = usba_readl(udc, INT_STA) & int_enb;
+	status = usba_readl(udc, INT_STA) & (int_enb | USBA_HIGH_SPEED);
 	DBG(DBG_INT, "irq, status=%#08x\n", status);
 	if (status & USBA_DET_SUSPEND) {

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