From nobody Sat Jun 13 09:39:40 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id F3A123C554B; Fri, 8 May 2026 09:51:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778233879; cv=none; b=PgpMSEaonbmpAjI1FYox1q8z9QehJ8AkXF+HgJkNm3DJch8HhQYWL3zQT7ke6l02tYJcn6SK20WSEqlNmvpa+8vd9gBqlRRiz7jCkAQL6Y7auy3wbOY41qdLpOu9MXIHdpV7EMGwnu2vhtd7VbLlfIEj0eOCHmqYV+81WVuffGA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778233879; c=relaxed/simple; bh=1mXFFKF1dPf7BWJnw0/0ZdqTCwv+sOJ/6jrp+H/xCgk=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:To:Cc; b=u7w5IDFW5rfa10SydGVkpnxxUHq+ujabGUyMj7KdyCRYyUQxg4qgEJAQi9o6r8qFbYBBi82REvm3m5PIvnyaXQiVOOJSYnlFM+Ai/zGd0olgYD1jKOdph43ZLfYpdBm8UHD9+gdeuMDgVRWVbZ0YlaI4ByJPD1s/NnFSBTm4ubE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Ui1qPHeN; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Ui1qPHeN" Received: by smtp.kernel.org (Postfix) with ESMTPS id 2FAABC32786; Fri, 8 May 2026 09:51:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1778233878; bh=1mXFFKF1dPf7BWJnw0/0ZdqTCwv+sOJ/6jrp+H/xCgk=; h=From:Date:Subject:To:Cc:Reply-To:From; b=Ui1qPHeN/SfZ1xTtfY+wjgQNbb0a9t+QMVLjmWBeRze06ubv3G/V6y6BJpbdcvTGK 1SSX1Obz821A89qTksACU9hhXCWThfBWnxdY2t1PoQEQWS6iEo/S3xr0VQUd41Ubi/ /M1RXypkEtQ8YW/ZIW995EhDKe8SObje+vO90EBbwI0IwRcPX2fp61ljZch3lBJhO1 xNIc3zdKtgGa+1nDptX8L2hZBK8814Unza4XrggSDcu/bGSaoQN1MtZNmSnK2NkjPT wrX6Y8PxB0adLsu1a+gfngH7G+qq26Gdipqz9Ajy53VUDqa06sJQlqtEKtINOVZgcG i6Xt7RqzOAexA== Received: from aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id EC8ABCD3447; Fri, 8 May 2026 09:51:17 +0000 (UTC) From: Pawel Laszczak via B4 Relay Date: Fri, 08 May 2026 12:06:39 +0200 Subject: [PATCH v3] usb: cdnsp: Add support for device-only configuration Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20260508-no_drd_config-v3-1-0614f5044721@cadence.com> X-B4-Tracking: v=1; b=H4sIAK61/WkC/yXMTQ5AMBBA4avIrDUp4ieuIiLVmTIWrbSIRNxds fwW710QyDMFaJMLPB0c2NmIIk1Az8pOJBijIZd5JUvZCOsG9DhoZw1PglRdYYamqVUBsVk9GT6 /X9f/Dvu4kN7eCdz3A3TPUF9xAAAA X-Change-ID: 20260508-no_drd_config-ea76d1df87a3 To: Peter Chen , Roger Quadros , Greg Kroah-Hartman , Bjorn Helgaas Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, Pawel Laszczak X-Mailer: b4 0.15.1 X-Developer-Signature: v=1; a=ed25519-sha256; t=1778234813; l=13735; i=pawell@cadence.com; h=from:subject:message-id; bh=eob8YUk5Cc1H/Q9UO05mmC3MRyfXop55OMzN4ymHMIE=; b=zcPIuwSdnmA3hiW1fy9l6iHlXNmz5OM+5anpH6hlFxJNaPaXxvP5nojtAsavpMVCoyRyibwZt ToNMGUFrbg4Cfip5MpRdRV7KNZBBCESE/zbEj0dEfb5XTG5Uc87oHyV X-Developer-Key: i=pawell@cadence.com; a=ed25519; pk=EUPBvLO9CDg7j6defeDl2iqi+z5Ivqu4Z46aiqe7dYc= X-Endpoint-Received: by B4 Relay for pawell@cadence.com/default with auth_id=707 X-Original-From: Pawel Laszczak Reply-To: pawell@cadence.com From: Pawel Laszczak This patch introduces support for the Cadence USBSSP (cdnsp) controller in hardware configurations where the Dual-Role Device (DRD) register block is not implemented or is inaccessible. In such cases, the driver cannot rely on the DRD logic to manage roles and must operate exclusively in a fixed peripheral/host mode. The change in BAR indexing (from BAR 2 to BAR 1) is a direct consequence of the 32-bit addressing used in this specific DRD-disabled hardware layout, compared to the 64-bit addressing used in DRD-enabled configurations. Tested on a PCI platform with a hardware configuration that lacks DRD support. Platform-side changes are included to support the PCI glue layer's property injection to handle this specific layout. Acked-by: Bjorn Helgaas # pci_ids.h Signed-off-by: Pawel Laszczak Acked-by: Peter Chen --- v3: - Improved descriptions and comments for better clarity. - Introduced the 'no_drd' property to indicate missing DRD register block. - Added support for fixed host-only and device-only configurations. - Ensured cdns_otg_disable_irq is called only when no_drd is false. - Updated cdns_drd_gadget_on/off to ensure PHY mode is correctly=20 handled even if DRD is disabled. v2: - Changed otg_irq to be optionali. - Added cdns->no_drd check in cdns_power_is_lost. - Added cdns->no_drd check in cdns_get_id. --- drivers/usb/cdns3/cdns3-plat.c | 26 ++++++++++++++---------- drivers/usb/cdns3/cdnsp-pci.c | 46 +++++++++++++++++++++++++++++++++-----= ---- drivers/usb/cdns3/core.c | 3 ++- drivers/usb/cdns3/core.h | 4 ++++ drivers/usb/cdns3/drd.c | 44 ++++++++++++++++++++++++++++++++++++++= -- include/linux/pci_ids.h | 1 + 6 files changed, 101 insertions(+), 23 deletions(-) diff --git a/drivers/usb/cdns3/cdns3-plat.c b/drivers/usb/cdns3/cdns3-plat.c index 3fe3109a3688..86c963a072db 100644 --- a/drivers/usb/cdns3/cdns3-plat.c +++ b/drivers/usb/cdns3/cdns3-plat.c @@ -81,6 +81,7 @@ static int cdns3_plat_probe(struct platform_device *pdev) if (cdns->pdata && cdns->pdata->override_apb_timeout) cdns->override_apb_timeout =3D cdns->pdata->override_apb_timeout; =20 + cdns->no_drd =3D device_property_read_bool(dev, "no_drd"); platform_set_drvdata(pdev, cdns); =20 ret =3D platform_get_irq_byname(pdev, "host"); @@ -113,21 +114,24 @@ static int cdns3_plat_probe(struct platform_device *p= dev) =20 cdns->dev_regs =3D regs; =20 - cdns->otg_irq =3D platform_get_irq_byname(pdev, "otg"); - if (cdns->otg_irq < 0) - return dev_err_probe(dev, cdns->otg_irq, - "Failed to get otg IRQ\n"); - - res =3D platform_get_resource_byname(pdev, IORESOURCE_MEM, "otg"); - if (!res) { - dev_err(dev, "couldn't get otg resource\n"); - return -ENXIO; + if (!cdns->no_drd) { + cdns->otg_irq =3D platform_get_irq_byname(pdev, "otg"); + if (cdns->otg_irq < 0) + return dev_err_probe(dev, cdns->otg_irq, + "Failed to get otg IRQ\n"); + + res =3D platform_get_resource_byname(pdev, IORESOURCE_MEM, "otg"); + if (!res) { + dev_err(dev, "couldn't get otg resource\n"); + return -ENXIO; + } + cdns->otg_res =3D *res; + } else { + dev_dbg(dev, "No DRD support\n"); } =20 cdns->phyrst_a_enable =3D device_property_read_bool(dev, "cdns,phyrst-a-e= nable"); =20 - cdns->otg_res =3D *res; - cdns->wakeup_irq =3D platform_get_irq_byname_optional(pdev, "wakeup"); if (cdns->wakeup_irq =3D=3D -EPROBE_DEFER) return cdns->wakeup_irq; diff --git a/drivers/usb/cdns3/cdnsp-pci.c b/drivers/usb/cdns3/cdnsp-pci.c index 432007cfe695..992700479172 100644 --- a/drivers/usb/cdns3/cdnsp-pci.c +++ b/drivers/usb/cdns3/cdnsp-pci.c @@ -19,6 +19,7 @@ =20 struct cdnsp_wrap { struct platform_device *plat_dev; + struct property_entry prop[3]; struct resource dev_res[6]; int devfn; }; @@ -29,10 +30,15 @@ struct cdnsp_wrap { #define RES_HOST_ID 3 #define RES_DEV_ID 4 #define RES_DRD_ID 5 - +/* DRD PCI configuration - 64-bit addressing */ +/* First PCI function */ #define PCI_BAR_HOST 0 -#define PCI_BAR_OTG 0 #define PCI_BAR_DEV 2 +/* Second PCI function */ +#define PCI_BAR_OTG 0 +/* Device only PCI configuration - 32-bit addressing */ +/* First PCI function */ +#define PCI_BAR_ONLY_DEV 1 =20 #define PCI_DEV_FN_HOST_DEVICE 0 #define PCI_DEV_FN_OTG 1 @@ -65,6 +71,7 @@ static int cdnsp_pci_probe(struct pci_dev *pdev, struct cdnsp_wrap *wrap; struct resource *res; struct pci_dev *func; + bool no_drd =3D false; int ret =3D 0; =20 /* @@ -75,11 +82,14 @@ static int cdnsp_pci_probe(struct pci_dev *pdev, pdev->devfn !=3D PCI_DEV_FN_OTG)) return -EINVAL; =20 + if (pdev->device =3D=3D PCI_DEVICE_ID_CDNS_UDC_USBSSP) + no_drd =3D true; + func =3D cdnsp_get_second_fun(pdev); - if (!func) + if (!func && !no_drd) return -EINVAL; =20 - if (func->class =3D=3D PCI_CLASS_SERIAL_USB_XHCI || + if ((func && func->class =3D=3D PCI_CLASS_SERIAL_USB_XHCI) || pdev->class =3D=3D PCI_CLASS_SERIAL_USB_XHCI) { ret =3D -EINVAL; goto put_pci; @@ -93,7 +103,7 @@ static int cdnsp_pci_probe(struct pci_dev *pdev, =20 pci_set_master(pdev); =20 - if (pci_is_enabled(func)) { + if (func && pci_is_enabled(func)) { wrap =3D pci_get_drvdata(func); } else { wrap =3D kzalloc_obj(*wrap); @@ -106,10 +116,12 @@ static int cdnsp_pci_probe(struct pci_dev *pdev, res =3D wrap->dev_res; =20 if (pdev->devfn =3D=3D PCI_DEV_FN_HOST_DEVICE) { + int bar_dev =3D no_drd ? PCI_BAR_ONLY_DEV : PCI_BAR_DEV; + /* Function 0: host(BAR_0) + device(BAR_2). */ dev_dbg(&pdev->dev, "Initialize Device resources\n"); - res[RES_DEV_ID].start =3D pci_resource_start(pdev, PCI_BAR_DEV); - res[RES_DEV_ID].end =3D pci_resource_end(pdev, PCI_BAR_DEV); + res[RES_DEV_ID].start =3D pci_resource_start(pdev, bar_dev); + res[RES_DEV_ID].end =3D pci_resource_end(pdev, bar_dev); res[RES_DEV_ID].name =3D "dev"; res[RES_DEV_ID].flags =3D IORESOURCE_MEM; dev_dbg(&pdev->dev, "USBSSP-DEV physical base addr: %pa\n", @@ -145,9 +157,20 @@ static int cdnsp_pci_probe(struct pci_dev *pdev, wrap->dev_res[RES_IRQ_OTG_ID].flags =3D IORESOURCE_IRQ; } =20 - if (pci_is_enabled(func)) { + if (no_drd || pci_is_enabled(func)) { + u8 idx =3D 0; + /* set up platform device info */ pdata.override_apb_timeout =3D CHICKEN_APB_TIMEOUT_VALUE; + + if (no_drd) { + wrap->prop[idx++] =3D PROPERTY_ENTRY_STRING("dr_mode", "peripheral"); + wrap->prop[idx++] =3D PROPERTY_ENTRY_BOOL("no_drd"); + } else { + wrap->prop[idx++] =3D PROPERTY_ENTRY_STRING("dr_mode", "otg"); + wrap->prop[idx++] =3D PROPERTY_ENTRY_BOOL("usb-role-switch"); + } + memset(&plat_info, 0, sizeof(plat_info)); plat_info.parent =3D &pdev->dev; plat_info.fwnode =3D pdev->dev.fwnode; @@ -158,6 +181,7 @@ static int cdnsp_pci_probe(struct pci_dev *pdev, plat_info.dma_mask =3D pdev->dma_mask; plat_info.data =3D &pdata; plat_info.size_data =3D sizeof(pdata); + plat_info.properties =3D wrap->prop; wrap->devfn =3D pdev->devfn; /* register platform device */ wrap->plat_dev =3D platform_device_register_full(&plat_info); @@ -185,13 +209,17 @@ static void cdnsp_pci_remove(struct pci_dev *pdev) if (wrap->devfn =3D=3D pdev->devfn) platform_device_unregister(wrap->plat_dev); =20 - if (!pci_is_enabled(func)) + if (!func || !pci_is_enabled(func)) kfree(wrap); =20 pci_dev_put(func); } =20 static const struct pci_device_id cdnsp_pci_ids[] =3D { + { PCI_DEVICE(PCI_VENDOR_ID_CDNS, PCI_DEVICE_ID_CDNS_UDC_USBSSP), + .class =3D PCI_CLASS_SERIAL_USB_DEVICE }, + { PCI_DEVICE(PCI_VENDOR_ID_CDNS, PCI_DEVICE_ID_CDNS_UDC_USBSSP), + .class =3D PCI_CLASS_SERIAL_USB_CDNS }, { PCI_DEVICE(PCI_VENDOR_ID_CDNS, PCI_DEVICE_ID_CDNS_USBSSP), .class =3D PCI_CLASS_SERIAL_USB_DEVICE }, { PCI_DEVICE(PCI_VENDOR_ID_CDNS, PCI_DEVICE_ID_CDNS_USBSSP), diff --git a/drivers/usb/cdns3/core.c b/drivers/usb/cdns3/core.c index 6a8d1fefbc0d..504bdf13ea80 100644 --- a/drivers/usb/cdns3/core.c +++ b/drivers/usb/cdns3/core.c @@ -70,7 +70,8 @@ static void cdns_role_stop(struct cdns *cdns) static void cdns_exit_roles(struct cdns *cdns) { cdns_role_stop(cdns); - cdns_drd_exit(cdns); + if (!cdns->no_drd) + cdns_drd_exit(cdns); } =20 /** diff --git a/drivers/usb/cdns3/core.h b/drivers/usb/cdns3/core.h index bca973b999a4..8c492fda924c 100644 --- a/drivers/usb/cdns3/core.h +++ b/drivers/usb/cdns3/core.h @@ -84,6 +84,9 @@ struct cdns3_platform_data { * value in CHICKEN_BITS_3 will be preserved. * @gadget_init: pointer to gadget initialization function * @host_init: pointer to host initialization function + * @no_drd: DRD register block is inaccessible. The controller is hardwire= d to + * single role (host or device) or the logic for role switching is + * missing. */ struct cdns { struct device *dev; @@ -124,6 +127,7 @@ struct cdns { u32 override_apb_timeout; int (*gadget_init)(struct cdns *cdns); int (*host_init)(struct cdns *cdns); + bool no_drd; }; =20 int cdns_hw_role_switch(struct cdns *cdns); diff --git a/drivers/usb/cdns3/drd.c b/drivers/usb/cdns3/drd.c index 84fb38a5723a..f87cf85cb97a 100644 --- a/drivers/usb/cdns3/drd.c +++ b/drivers/usb/cdns3/drd.c @@ -87,6 +87,9 @@ int cdns_get_id(struct cdns *cdns) { int id; =20 + if (cdns->no_drd) + return 0; + id =3D readl(&cdns->otg_regs->sts) & OTGSTS_ID_VALUE; dev_dbg(cdns->dev, "OTG ID: %d", id); =20 @@ -107,7 +110,7 @@ void cdns_clear_vbus(struct cdns *cdns) { u32 reg; =20 - if (cdns->version !=3D CDNSP_CONTROLLER_V2) + if (cdns->version !=3D CDNSP_CONTROLLER_V2 || cdns->no_drd) return; =20 reg =3D readl(&cdns->otg_cdnsp_regs->override); @@ -120,7 +123,7 @@ void cdns_set_vbus(struct cdns *cdns) { u32 reg; =20 - if (cdns->version !=3D CDNSP_CONTROLLER_V2) + if (cdns->version !=3D CDNSP_CONTROLLER_V2 || cdns->no_drd) return; =20 reg =3D readl(&cdns->otg_cdnsp_regs->override); @@ -181,6 +184,9 @@ int cdns_drd_host_on(struct cdns *cdns) u32 val, ready_bit; int ret; =20 + if (cdns->no_drd) + goto phy_set; + /* Enable host mode. */ writel(OTGCMD_HOST_BUS_REQ | OTGCMD_OTG_DIS, &cdns->otg_regs->cmd); @@ -197,6 +203,7 @@ int cdns_drd_host_on(struct cdns *cdns) if (ret) dev_err(cdns->dev, "timeout waiting for xhci_ready\n"); =20 +phy_set: phy_set_mode(cdns->usb2_phy, PHY_MODE_USB_HOST); phy_set_mode(cdns->usb3_phy, PHY_MODE_USB_HOST); return ret; @@ -210,6 +217,9 @@ void cdns_drd_host_off(struct cdns *cdns) { u32 val; =20 + if (cdns->no_drd) + goto phy_set; + writel(OTGCMD_HOST_BUS_DROP | OTGCMD_DEV_BUS_DROP | OTGCMD_DEV_POWER_OFF | OTGCMD_HOST_POWER_OFF, &cdns->otg_regs->cmd); @@ -218,6 +228,8 @@ void cdns_drd_host_off(struct cdns *cdns) readl_poll_timeout_atomic(&cdns->otg_regs->state, val, !(val & OTGSTATE_HOST_STATE_MASK), 1, 2000000); + +phy_set: phy_set_mode(cdns->usb2_phy, PHY_MODE_INVALID); phy_set_mode(cdns->usb3_phy, PHY_MODE_INVALID); } @@ -234,6 +246,9 @@ int cdns_drd_gadget_on(struct cdns *cdns) u32 ready_bit; int ret, val; =20 + if (cdns->no_drd) + goto phy_set; + /* switch OTG core */ writel(OTGCMD_DEV_BUS_REQ | reg, &cdns->otg_regs->cmd); =20 @@ -251,6 +266,7 @@ int cdns_drd_gadget_on(struct cdns *cdns) return ret; } =20 +phy_set: phy_set_mode(cdns->usb2_phy, PHY_MODE_USB_DEVICE); phy_set_mode(cdns->usb3_phy, PHY_MODE_USB_DEVICE); return 0; @@ -265,6 +281,9 @@ void cdns_drd_gadget_off(struct cdns *cdns) { u32 val; =20 + if (cdns->no_drd) + goto phy_set; + /* * Driver should wait at least 10us after disabling Device * before turning-off Device (DEV_BUS_DROP). @@ -277,6 +296,8 @@ void cdns_drd_gadget_off(struct cdns *cdns) readl_poll_timeout_atomic(&cdns->otg_regs->state, val, !(val & OTGSTATE_DEV_STATE_MASK), 1, 2000000); + +phy_set: phy_set_mode(cdns->usb2_phy, PHY_MODE_INVALID); phy_set_mode(cdns->usb3_phy, PHY_MODE_INVALID); } @@ -392,6 +413,19 @@ int cdns_drd_init(struct cdns *cdns) u32 state, reg; int ret; =20 + if (cdns->no_drd) { + cdns->dr_mode =3D usb_get_dr_mode(cdns->dev); + cdns->version =3D CDNSP_CONTROLLER_V2; + + if (cdns->dr_mode !=3D USB_DR_MODE_HOST && + cdns->dr_mode !=3D USB_DR_MODE_PERIPHERAL) { + dev_err(cdns->dev, "Incorrect dr_mode\n"); + return -EINVAL; + } + + return 0; + } + regs =3D devm_ioremap_resource(cdns->dev, &cdns->otg_res); if (IS_ERR(regs)) return PTR_ERR(regs); @@ -492,6 +526,9 @@ int cdns_drd_init(struct cdns *cdns) =20 int cdns_drd_exit(struct cdns *cdns) { + if (cdns->no_drd) + return 0; + cdns_otg_disable_irq(cdns); =20 return 0; @@ -500,6 +537,9 @@ int cdns_drd_exit(struct cdns *cdns) /* Indicate the cdns3 core was power lost before */ bool cdns_power_is_lost(struct cdns *cdns) { + if (cdns->no_drd) + return false; + if (cdns->version =3D=3D CDNS3_CONTROLLER_V0) { if (!(readl(&cdns->otg_v0_regs->simulate) & BIT(0))) return true; diff --git a/include/linux/pci_ids.h b/include/linux/pci_ids.h index 24cb42f66e4b..a6b9b6f6d8cc 100644 --- a/include/linux/pci_ids.h +++ b/include/linux/pci_ids.h @@ -2424,6 +2424,7 @@ #define PCI_DEVICE_ID_CDNS_USBSS 0x0100 #define PCI_DEVICE_ID_CDNS_USB 0x0120 #define PCI_DEVICE_ID_CDNS_USBSSP 0x0200 +#define PCI_DEVICE_ID_CDNS_UDC_USBSSP 0x0400 =20 #define PCI_VENDOR_ID_ARECA 0x17d3 #define PCI_DEVICE_ID_ARECA_1110 0x1110 --- base-commit: 17c7841d09ee7d33557fd075562d9289b6018c90 change-id: 20260508-no_drd_config-ea76d1df87a3 Best regards, -- =20 Pawel Laszczak