From nobody Sat Sep 26 22:56:28 2026 Received: from cstnet.cn (smtp21.cstnet.cn [159.226.251.21]) (using TLSv1.2 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BDD2943785F; Fri, 28 Aug 2026 11:42:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=159.226.251.21 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787917346; cv=none; b=NMSja8rehVynZjIOJE7DfkQK5WFVp9eHkAklFn58KqKWtZ8/ytcRMrPW6YSdNT/kyPNI+aGG+8R5iTouNsLfQWvieU/tcfuY188dwrfDDnASkqiP2iEDzIBbPHIZo7cSibtcXT6tzyA61HiXr/ATY52eQVucJrR+oX7cw9WJQQU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787917346; c=relaxed/simple; bh=UrRRrRGioU2jwFOT4R0dWftSuqJLymr8z94go2/Ju7k=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=mtNBbk0D04mNkZVrpynqBLTncHSzNpOzD/h+rRExK4In4Becq+MEJGVMPE5BVpzgedbh+EFv3im7splmTG/v9XwdNhDDQGbyMsMd/XvF0aarKSbvTGR3FbnCwPKdeahZKgHt0CC8V55vQksfINYXcVJ0QcPijtDr7zCoAZVBk1U= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=iscas.ac.cn; spf=pass smtp.mailfrom=iscas.ac.cn; arc=none smtp.client-ip=159.226.251.21 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=iscas.ac.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=iscas.ac.cn Received: from localhost.localdomain (unknown [111.196.241.250]) by APP-01 (Coremail) with SMTP id qwCowABnO+8SdJFqoBO+Bg--.43429S2; Fri, 28 Aug 2026 19:42:10 +0800 (CST) From: Pengpeng Hou To: Greg Kroah-Hartman , Thierry Reding Cc: Pengpeng Hou , Jonathan Hunter , linux-usb@vger.kernel.org, linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [RFC PATCH] usb: gadget: tegra-xudc: Unwind device-mode power failures Date: Fri, 28 Aug 2026 19:42:08 +0800 Message-ID: <20260828114208.49341-1-pengpeng@iscas.ac.cn> X-Mailer: git-send-email 2.50.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: qwCowABnO+8SdJFqoBO+Bg--.43429S2 X-Coremail-Antispam: 1UD129KBjvJXoWxZF4ktF4ftFWxtF1kZw1kZrb_yoW5Cr17pa 1jgFW5J3ykX3sxKFnaq3yqvr15G3ykG348X34Iyay29rsrK34DJry7trWIqFW8Gr93Jr4j yr4xK342yr9rWF7anT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUvj14x267AKxVW8JVW5JwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2AK02 1l84ACjcxK6xIIjxv20xvE14v26ryj6F1UM28EF7xvwVC0I7IYx2IY6xkF7I0E14v26r4U JVWxJr1l84ACjcxK6I8E87Iv67AKxVW0oVCq3wA2z4x0Y4vEx4A2jsIEc7CjxVAFwI0_Gc CE3s1le2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xvF2IEw4CE5I8CrVC2j2WlYx0E 2Ix0cI8IcVAFwI0_JrI_JrylYx0Ex4A2jsIE14v26r4j6F4UMcvjeVCFs4IE7xkEbVWUJV W8JwACjcxG0xvY0x0EwIxGrwACjI8F5VA0II8E6IAqYI8I648v4I1lc7CjxVAaw2AFwI0_ JF0_Jw1l42xK82IYc2Ij64vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG67 AKxVWUJVWUGwC20s026x8GjcxK67AKxVWUGVWUWwC2zVAF1VAY17CE14v26r126r1DMIIY rxkI7VAKI48JMIIF0xvE2Ix0cI8IcVAFwI0_Xr0_Ar1lIxAIcVC0I7IYx2IY6xkF7I0E14 v26r4UJVWxJr1lIxAIcVCF04k26cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r4j 6F4UMIIF0xvEx4A2jsIEc7CjxVAFwI0_Gr1j6F4UJbIYCTnIWIevJa73UjIFyTuYvjfUYf HjUUUUU X-CM-SenderInfo: pshqw1xhqjqxpvfd2hldfou0/ Content-Type: text/plain; charset="utf-8" The Tegra XUDC role worker ignores runtime-PM, PHY power and PHY mode failures while entering device mode, and sets current_device_mode even after an incomplete transition. Acquire runtime PM with pm_runtime_resume_and_get(), unwind each completed PHY and pad operation on failure, and only publish current_device_mode after all steps succeed. The worker logs the error. This is an RFC because the asynchronous role request has already completed and maintainers may prefer retry or desired-role state handling beyond local rollback. The issue was identified via static analysis and manually reviewed. Assisted-by: LLM Signed-off-by: Pengpeng Hou --- drivers/usb/gadget/udc/tegra-xudc.c | 38 ++++++++++++++++++++++------- 1 file changed, 29 insertions(+), 9 deletions(-) diff --git a/drivers/usb/gadget/udc/tegra-xudc.c b/drivers/usb/gadget/udc/t= egra-xudc.c index e9d33be02866..41015e5dc089 100644 --- a/drivers/usb/gadget/udc/tegra-xudc.c +++ b/drivers/usb/gadget/udc/tegra-xudc.c @@ -696,28 +696,43 @@ static void tegra_xudc_restore_port_speed(struct tegr= a_xudc *xudc) xudc_writel(xudc, val, SSPX_CORE_CNT72); } =20 -static void tegra_xudc_device_mode_on(struct tegra_xudc *xudc) +static int tegra_xudc_device_mode_on(struct tegra_xudc *xudc) { int err; =20 - pm_runtime_get_sync(xudc->dev); + err =3D pm_runtime_resume_and_get(xudc->dev); + if (err < 0) + return err; =20 tegra_phy_xusb_utmi_pad_power_on(xudc->curr_utmi_phy); =20 err =3D phy_power_on(xudc->curr_utmi_phy); if (err < 0) - dev_err(xudc->dev, "UTMI power on failed: %d\n", err); + goto power_down_pad; =20 err =3D phy_power_on(xudc->curr_usb3_phy); if (err < 0) - dev_err(xudc->dev, "USB3 PHY power on failed: %d\n", err); + goto power_off_utmi; =20 dev_dbg(xudc->dev, "device mode on\n"); =20 - phy_set_mode_ext(xudc->curr_utmi_phy, PHY_MODE_USB_OTG, - USB_ROLE_DEVICE); + err =3D phy_set_mode_ext(xudc->curr_utmi_phy, PHY_MODE_USB_OTG, + USB_ROLE_DEVICE); + if (err < 0) + goto power_off_usb3; =20 xudc->current_device_mode =3D true; + + return 0; + +power_off_usb3: + phy_power_off(xudc->curr_usb3_phy); +power_off_utmi: + phy_power_off(xudc->curr_utmi_phy); +power_down_pad: + tegra_phy_xusb_utmi_pad_power_down(xudc->curr_utmi_phy); + pm_runtime_put(xudc->dev); + return err; } =20 static void tegra_xudc_device_mode_off(struct tegra_xudc *xudc) @@ -779,11 +794,16 @@ static void tegra_xudc_usb_role_sw_work(struct work_s= truct *work) { struct tegra_xudc *xudc =3D container_of(work, struct tegra_xudc, usb_role_sw_work); + int err; =20 - if (xudc->device_mode) - tegra_xudc_device_mode_on(xudc); - else + if (xudc->device_mode) { + err =3D tegra_xudc_device_mode_on(xudc); + + if (err) + dev_err(xudc->dev, "failed to enter device mode: %d\n", err); + } else { tegra_xudc_device_mode_off(xudc); + } } =20 static int tegra_xudc_get_phy_index(struct tegra_xudc *xudc, --=20 2.43.0