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authorJohn Stultz <john.stultz@linaro.org>2017-01-24 01:59:35 +0300
committerFelipe Balbi <felipe.balbi@linux.intel.com>2017-01-24 17:19:09 +0300
commitfc30c4bb44a3665edcc76bd7af93f009bc9dc672 (patch)
treec35aa7293aa1ad294ef361908e8a208b5a0fb82d
parent6e6360b67d12370638ad1bc8943cc63d4c89da27 (diff)
downloadlinux-fc30c4bb44a3665edcc76bd7af93f009bc9dc672.tar.xz
usb: dwc2: Workaround case where GOTGCTL state is wrong
When removing a USB-A to USB-otg adapter cable, we get a change status irq, and then in dwc2_conn_id_status_change, we erroneously see the GOTGCTL_CONID_B flag set. This causes us to get stuck in the "while (!dwc2_is_device_mode(hsotg))" loop, spitting out "Waiting for Peripheral Mode, Mode=Host" warnings until it fails out many seconds later. This patch works around the issue by re-reading the GOTGCTL state to check if the GOTGCTL_CONID_B is still set and if not restarting the change status logic. Cc: Wei Xu <xuwei5@hisilicon.com> Cc: Guodong Xu <guodong.xu@linaro.org> Cc: Amit Pundir <amit.pundir@linaro.org> Cc: Rob Herring <robh+dt@kernel.org> Cc: John Youn <johnyoun@synopsys.com> Cc: Douglas Anderson <dianders@chromium.org> Cc: Chen Yu <chenyu56@huawei.com> Cc: Vardan Mikayelyan <mvardan@synopsys.com> Cc: Kishon Vijay Abraham I <kishon@ti.com> Cc: Felipe Balbi <felipe.balbi@linux.intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: linux-usb@vger.kernel.org Reviewed-by: Vardan Mikayelyan <mvardan@synopsys.com> Signed-off-by: John Stultz <john.stultz@linaro.org> Signed-off-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
-rw-r--r--drivers/usb/dwc2/hcd.c9
1 files changed, 9 insertions, 0 deletions
diff --git a/drivers/usb/dwc2/hcd.c b/drivers/usb/dwc2/hcd.c
index 8b688b041696..e0d152f2c81b 100644
--- a/drivers/usb/dwc2/hcd.c
+++ b/drivers/usb/dwc2/hcd.c
@@ -3237,6 +3237,14 @@ static void dwc2_conn_id_status_change(struct work_struct *work)
dwc2_is_host_mode(hsotg) ? "Host" :
"Peripheral");
msleep(20);
+ /*
+ * Sometimes the initial GOTGCTRL read is wrong, so
+ * check it again and jump to host mode if that was
+ * the case.
+ */
+ gotgctl = dwc2_readl(hsotg->regs + GOTGCTL);
+ if (!(gotgctl & GOTGCTL_CONID_B))
+ goto host;
if (++count > 250)
break;
}
@@ -3251,6 +3259,7 @@ static void dwc2_conn_id_status_change(struct work_struct *work)
spin_unlock_irqrestore(&hsotg->lock, flags);
dwc2_hsotg_core_connect(hsotg);
} else {
+host:
/* A-Device connector (Host Mode) */
dev_dbg(hsotg->dev, "connId A\n");
while (!dwc2_is_host_mode(hsotg)) {