According to the xHCI spec "4.23.2 xHCI Power Management", the CRR bit
of CRCR register should be zero before setting Run/Stop (R/S) = '0'.
Otherwise, the STS_HALT is not set until the CRR is cleared on specific
xHCI controllers. In case of R-Car SoCs, it spent about 90 ms to clear
the CRR. So, to avoid the quirks XHCI_SLOW_SUSPEND, the driver calls
the aborting function if the CRR is set to 1.

Signed-off-by: Yoshihiro Shimoda <[email protected]>
---
 drivers/usb/host/xhci-ring.c |  2 +-
 drivers/usb/host/xhci.c      | 21 ++++++++++++++++++++-
 drivers/usb/host/xhci.h      |  1 +
 3 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index f5397a5..21f3932 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -280,7 +280,7 @@ void xhci_ring_cmd_db(struct xhci_hcd *xhci)
        readl(&xhci->dba->doorbell[0]);
 }
 
-static int xhci_abort_cmd_ring(struct xhci_hcd *xhci)
+int xhci_abort_cmd_ring(struct xhci_hcd *xhci)
 {
        u64 temp_64;
        int ret;
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index ec8ac16..d2d81a0 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -892,7 +892,7 @@ static void xhci_disable_port_wake_on_bits(struct xhci_hcd 
*xhci)
  */
 int xhci_suspend(struct xhci_hcd *xhci, bool do_wakeup)
 {
-       int                     rc = 0;
+       int                     rc = 0, ret;
        unsigned int            delay = XHCI_MAX_HALT_USEC;
        struct usb_hcd          *hcd = xhci_to_hcd(xhci);
        u32                     command;
@@ -918,6 +918,25 @@ int xhci_suspend(struct xhci_hcd *xhci, bool do_wakeup)
        /* step 1: stop endpoint */
        /* skipped assuming that port suspend has done */
 
+       /*
+        * According to the xHCI spec "4.23.2 xHCI Power Management", the CRR
+        * bit of CRCR register should be zero before setting Run/Stop (R/S) =
+        * '0', the driver calls the aborting function if the CRR is set to 1.
+        */
+       if (xhci_read_64(xhci, &xhci->op_regs->cmd_ring) & CMD_RING_RUNNING) {
+               /* unlock here because this may wait about 5 seconds */
+               spin_unlock_irq(&xhci->lock);
+               ret = xhci_abort_cmd_ring(xhci);
+               if (unlikely(ret == -ESHUTDOWN)) {
+                       xhci_err(xhci, "Abort command ring failed\n");
+                       xhci_cleanup_command_queue(xhci);
+                       usb_hc_died(xhci_to_hcd(xhci)->primary_hcd);
+                       xhci_dbg(xhci, "xHCI host controller is dead.\n");
+                       return ret;
+               }
+               spin_lock_irq(&xhci->lock);
+       }
+
        /* step 2: clear Run/Stop bit */
        command = readl(&xhci->op_regs->command);
        command &= ~CMD_RUN;
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index 8e421b8..c861bf0 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1796,6 +1796,7 @@ struct xhci_segment *trb_in_td(struct xhci_hcd *xhci,
                union xhci_trb *end_trb, dma_addr_t suspect_dma, bool debug);
 int xhci_is_vendor_info_code(struct xhci_hcd *xhci, unsigned int 
trb_comp_code);
 void xhci_ring_cmd_db(struct xhci_hcd *xhci);
+int xhci_abort_cmd_ring(struct xhci_hcd *xhci);
 int xhci_queue_slot_control(struct xhci_hcd *xhci, struct xhci_command *cmd,
                u32 trb_type, u32 slot_id);
 int xhci_queue_address_device(struct xhci_hcd *xhci, struct xhci_command *cmd,
-- 
1.9.1

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