usb: renesas-xhci: Fix handling of unknown ROM state

The ROM load sometimes seems to return an unknown status
(RENESAS_ROM_STATUS_NO_RESULT) instead of success / fail.

If the ROM load indeed failed this leads to failures when trying to
communicate with the controller later on.

Attempt to load firmware using RAM load in those cases.

Fixes: 2478be82de44 ("usb: renesas-xhci: Add ROM loader for uPD720201")
Cc: stable@vger.kernel.org
Cc: Mathias Nyman <mathias.nyman@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Vinod Koul <vkoul@kernel.org>
Tested-by: Vinod Koul <vkoul@kernel.org>
Reviewed-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Moritz Fischer <mdf@kernel.org>
Link: https://lore.kernel.org/r/20210615153758.253572-1-mdf@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/host/xhci-pci-renesas.c b/drivers/usb/host/xhci-pci-renesas.c
index 5923844..1da6479 100644 (file)
--- a/drivers/usb/host/xhci-pci-renesas.c
+++ b/drivers/usb/host/xhci-pci-renesas.c
@@ -207,7 +207,8 @@ static int renesas_check_rom_state(struct pci_dev *pdev)
                        return 0;
 
                case RENESAS_ROM_STATUS_NO_RESULT: /* No result yet */
-                       return 0;
+                       dev_dbg(&pdev->dev, "Unknown ROM status ...\n");
+                       break;
 
                case RENESAS_ROM_STATUS_ERROR: /* Error State */
                default: /* All other states are marked as "Reserved states" */
@@ -224,13 +225,12 @@ static int renesas_fw_check_running(struct pci_dev *pdev)
        u8 fw_state;
        int err;
 
-       /* Check if device has ROM and loaded, if so skip everything */
-       err = renesas_check_rom(pdev);
-       if (err) { /* we have rom */
-               err = renesas_check_rom_state(pdev);
-               if (!err)
-                       return err;
-       }
+       /*
+        * Only if device has ROM and loaded FW we can skip loading and
+        * return success. Otherwise (even unknown state), attempt to load FW.
+        */
+       if (renesas_check_rom(pdev) && !renesas_check_rom_state(pdev))
+               return 0;
 
        /*
         * Test if the device is actually needing the firmware. As most