This is a note to let you know that I've just added the patch titled

usb: renesas-xhci: Prefer firmware loading on unknown ROM state

to my usb git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git in the usb-linus branch.

The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.)

The patch will hopefully also be merged in Linus's tree for the next -rc kernel release.

If you have any questions about this process, please let me know.

From c82cacd2f1e622a461a77d275a75d7e19e7635a3 Mon Sep 17 00:00:00 2001

From: Takashi Iwai tiwai@suse.de Date: Thu, 26 Aug 2021 14:41:27 +0200 Subject: usb: renesas-xhci: Prefer firmware loading on unknown ROM state

The recent attempt to handle an unknown ROM state in the commit d143825baf15 ("usb: renesas-xhci: Fix handling of unknown ROM state") resulted in a regression and reverted later by the commit 44cf53602f5a ("Revert "usb: renesas-xhci: Fix handling of unknown ROM state""). The problem of the former fix was that it treated the failure of firmware loading as a fatal error. Since the firmware files aren't included in the standard linux-firmware tree, most users don't have them, hence they got the non-working system after that. The revert fixed the regression, but also it didn't make the firmware loading triggered even on the devices that do need it. So we need still a fix for them.

This is another attempt to handle the unknown ROM state. Like the previous fix, this also tries to load the firmware when ROM shows unknown state. In this patch, however, the failure of a firmware loading (such as a missing firmware file) isn't handled as a fatal error any longer when ROM has been already detected, but it falls back to the ROM mode like before. The error is returned only when no ROM is detected and the firmware loading failed.

Along with it, for simplifying the code flow, the detection and the check of ROM is factored out from renesas_fw_check_running() and done in the caller side, renesas_xhci_check_request_fw(). It avoids the redundant ROM checks.

The patch was tested on Lenovo Thinkpad T14 gen (BIOS 1.34). Also it was confirmed that no regression is seen on another Thinkpad T14 machine that has worked without the patch, too.

Fixes: 44cf53602f5a ("Revert "usb: renesas-xhci: Fix handling of unknown ROM state"") Cc: stable stable@vger.kernel.org Signed-off-by: Takashi Iwai tiwai@suse.de BugLink: https://bugzilla.opensuse.org/show_bug.cgi?id=1189207 Link: https://lore.kernel.org/r/20210826124127.14789-1-tiwai@suse.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/usb/host/xhci-pci-renesas.c | 35 +++++++++++++++++++---------- 1 file changed, 23 insertions(+), 12 deletions(-)

diff --git a/drivers/usb/host/xhci-pci-renesas.c b/drivers/usb/host/xhci-pci-renesas.c index 5923844ed821..ef5e91a5542d 100644 --- 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"); + return -ENOENT;

case RENESAS_ROM_STATUS_ERROR: /* Error State */ default: /* All other states are marked as "Reserved states" */ @@ -224,14 +225,6 @@ 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; - } - /* * Test if the device is actually needing the firmware. As most * BIOSes will initialize the device for us. If the device is @@ -591,21 +584,39 @@ int renesas_xhci_check_request_fw(struct pci_dev *pdev, (struct xhci_driver_data *)id->driver_data; const char *fw_name = driver_data->firmware; const struct firmware *fw; + bool has_rom; int err;

+ /* Check if device has ROM and loaded, if so skip everything */ + has_rom = renesas_check_rom(pdev); + if (has_rom) { + err = renesas_check_rom_state(pdev); + if (!err) + return 0; + else if (err != -ENOENT) + has_rom = false; + } + err = renesas_fw_check_running(pdev); /* Continue ahead, if the firmware is already running. */ if (err == 0) return 0;

+ /* no firmware interface available */ if (err != 1) - return err; + return has_rom ? 0 : err;

pci_dev_get(pdev); - err = request_firmware(&fw, fw_name, &pdev->dev); + err = firmware_request_nowarn(&fw, fw_name, &pdev->dev); pci_dev_put(pdev); if (err) { - dev_err(&pdev->dev, "request_firmware failed: %d\n", err); + if (has_rom) { + dev_info(&pdev->dev, "failed to load firmware %s, fallback to ROM\n", + fw_name); + return 0; + } + dev_err(&pdev->dev, "failed to load firmware %s: %d\n", + fw_name, err); return err; }