[PATCH AUTOSEL 4.19 121/146] xhci: Avoid USB autosuspend when resuming USB2 ports.

Sasha Levin
2018-10-31T23:43:32Z

From: Anshuman Gupta <anshuman.gupta@intel.com>

[ Upstream commit 330e2d61cdd58363eb5e66b2e72f76fe3c5492e0 ]

When USB bus host controller root hub resumes from autosuspend,
it immediately tries to enter auto-suspend, but there can be a
scenario when root hub is resuming its usb2 ports, in that particular
case USB host controller auto suspend fails since it is busy
to resuming its usb2 ports.

This makes multiple failed cycles of auto-suspend until all usb2
ports of host controller root hub do not resume.

This patch uses USB core framework usb_hcd_start_port_resume,
usb_hcd_end_port_resume API's in order to autoresume/autosuspend
root hub properly.

Signed-off-by: Anshuman Gupta <anshuman.gupta@intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/usb/host/xhci-hub.c | 5 +++++
drivers/usb/host/xhci-ring.c | 1 +
2 files changed, 6 insertions(+)

diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c
index 7e2a531ba321..12eea73d9f20 100644
--- a/drivers/usb/host/xhci-hub.c
+++ b/drivers/usb/host/xhci-hub.c
@@ -900,6 +900,7 @@ static u32 xhci_get_port_status(struct usb_hcd *hcd,
set_bit(wIndex, &bus_state->resuming_ports);
bus_state->resume_done[wIndex] = timeout;
mod_timer(&hcd->rh_timer, timeout);
+ usb_hcd_start_port_resume(&hcd->self, wIndex);
}
/* Has resume been signalled for USB_RESUME_TIME yet? */
} else if (time_after_eq(jiffies,
@@ -940,6 +941,7 @@ static u32 xhci_get_port_status(struct usb_hcd *hcd,
clear_bit(wIndex, &bus_state->rexit_ports);
}

+ usb_hcd_end_port_resume(&hcd->self, wIndex);
bus_state->port_c_suspend |= 1 << wIndex;
bus_state->suspended_ports &= ~(1 << wIndex);
} else {
@@ -962,6 +964,7 @@ static u32 xhci_get_port_status(struct usb_hcd *hcd,
(raw_port_status & PORT_PLS_MASK) != XDEV_RESUME) {
bus_state->resume_done[wIndex] = 0;
clear_bit(wIndex, &bus_state->resuming_ports);
+ usb_hcd_end_port_resume(&hcd->self, wIndex);
}

@@ -1337,6 +1340,7 @@ int xhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
goto error;

set_bit(wIndex, &bus_state->resuming_ports);
+ usb_hcd_start_port_resume(&hcd->self, wIndex);
xhci_set_link_state(xhci, ports[wIndex],
XDEV_RESUME);
spin_unlock_irqrestore(&xhci->lock, flags);
@@ -1345,6 +1349,7 @@ int xhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
xhci_set_link_state(xhci, ports[wIndex],
XDEV_U0);
clear_bit(wIndex, &bus_state->resuming_ports);
+ usb_hcd_end_port_resume(&hcd->self, wIndex);
}
bus_state->port_c_suspend |= 1 << wIndex;

diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index f0a99aa0ac58..cd4659703647 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -1602,6 +1602,7 @@ static void handle_port_status(struct xhci_hcd *xhci,
set_bit(HCD_FLAG_POLL_RH, &hcd->flags);
mod_timer(&hcd->rh_timer,
bus_state->resume_done[hcd_portnum]);
+ usb_hcd_start_port_resume(&hcd->self, hcd_portnum);
bogus_port_status = true;
}
}
--
2.17.1