From 241e2ce88e5a494be7a5d44c0697592f1632fbee Mon Sep 17 00:00:00 2001 From: Pawel Laszczak Date: Fri, 18 Apr 2025 04:55:16 +0000 Subject: usb: cdnsp: Fix issue with resuming from L1 In very rare cases after resuming controller from L1 to L0 it reads registers before the clock UTMI have been enabled and as the result driver reads incorrect value. Most of registers are in APB domain clock but some of them (e.g. PORTSC) are in UTMI domain clock. After entering to L1 state the UTMI clock can be disabled. When controller transition from L1 to L0 the port status change event is reported and in interrupt runtime function driver reads PORTSC. During this read operation controller synchronize UTMI and APB domain but UTMI clock is still disabled and in result it reads 0xFFFFFFFF value. To fix this issue driver increases APB timeout value. The issue is platform specific and if the default value of APB timeout is not sufficient then this time should be set Individually for each platform. Fixes: 3d82904559f4 ("usb: cdnsp: cdns3 Add main part of Cadence USBSSP DRD Driver") Cc: stable Signed-off-by: Pawel Laszczak Acked-by: Peter Chen Link: https://lore.kernel.org/r/PH7PR07MB953846C57973E4DB134CAA71DDBF2@PH7PR07MB9538.namprd07.prod.outlook.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/cdns3/cdnsp-pci.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) (limited to 'drivers/usb/cdns3/cdnsp-pci.c') diff --git a/drivers/usb/cdns3/cdnsp-pci.c b/drivers/usb/cdns3/cdnsp-pci.c index a51144504ff33..8c361b8394e95 100644 --- a/drivers/usb/cdns3/cdnsp-pci.c +++ b/drivers/usb/cdns3/cdnsp-pci.c @@ -28,6 +28,8 @@ #define PCI_DRIVER_NAME "cdns-pci-usbssp" #define PLAT_DRIVER_NAME "cdns-usbssp" +#define CHICKEN_APB_TIMEOUT_VALUE 0x1C20 + static struct pci_dev *cdnsp_get_second_fun(struct pci_dev *pdev) { /* @@ -139,6 +141,14 @@ static int cdnsp_pci_probe(struct pci_dev *pdev, cdnsp->otg_irq = pdev->irq; } + /* + * Cadence PCI based platform require some longer timeout for APB + * to fixes domain clock synchronization issue after resuming + * controller from L1 state. + */ + cdnsp->override_apb_timeout = CHICKEN_APB_TIMEOUT_VALUE; + pci_set_drvdata(pdev, cdnsp); + if (pci_is_enabled(func)) { cdnsp->dev = dev; cdnsp->gadget_init = cdnsp_gadget_init; @@ -148,8 +158,6 @@ static int cdnsp_pci_probe(struct pci_dev *pdev, goto free_cdnsp; } - pci_set_drvdata(pdev, cdnsp); - device_wakeup_enable(&pdev->dev); if (pci_dev_run_wake(pdev)) pm_runtime_put_noidle(&pdev->dev); -- cgit v1.2.3