From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794599368; b=0A+UeobqsLLe+VWnXfTlhPcSSEDTtKlGS0BWEa3kMizrCZ7aJYhf4cBGWWYs3Nd2Q51/ hSOgaXetlM2D433sOAniKQhIW5wDjaB2niK8l8Fx959IkaCwmXZuK/PqS5rnRfS5r4SL3 Tk97YvT4LvH85fII6U5/sYKQqKdiHA6D/7KPjOFOBYzlmKPQITgeqmpkjw7v4JJ4ArBUl 5Tq+YdyM+80Siw6uCeuDIaSzoLYi0NfrByquVlRHx1dytLGAmhgSy9H2Pg5ObwOeUkrXb nJAJ4L5V3Toci8zLJaZse6OxeDZeWpoOYCrhbQjYdkaUjvEqFdsdH/pk5pSinMNApiw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794599368; h=Received:DKIM-Signature:Message-ID:From:Subject:Reply-To:To:Cc: In-Reply-To:References:Content-Type:Content-Transfer-Encoding:Date; bh=iYcv7Xupq4ln/cAbRdEA9fqeHs2mmZ7OQQsvxTxwXEM=; b=vy1g2aITBya7dYr2SKQVpNoMsHHmLpryOJyoPW9JnT/xMUXBZmzZRRGvz6NIVqErQ9aM fUbv+htPJFegRKZf3BsuDhRrUH4WEcQckZSS3CVQyXdbGcO3RTj7JxPFy1IKeMBlJV05M xowKlZJlKVVlM2qoFWCHmttRSoBoKarck1xGb1r/EE0yiDzcZVkRNm5aNIINMWXGQLxWq FgfbP7ipDnu7GN2JUUneHtaM3MbJ/aAr8xiuu5u/RJMOs60+aJSUn6Kn9rCj6h544lTOQ blHk83MfN+DwSsKxpWclZLjAVStnE9lixPf5fdzn7bUvMwWjmwUs6OTMcY31KacE3mQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=WoFMSNBJ; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 05A9F606A327 for ; Fri, 13 Nov 2026 19:49:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=WoFMSNBJ Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6D24E1F000C5; Fri, 13 Nov 2026 19:49:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794599367; bh=iYcv7Xupq4ln/cAbRdEA9fqeHs2mmZ7OQQsvxTxwXEM=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=WoFMSNBJ4lz0zr6eSy4jsGfutI2RkKLmGVQQFPs+V7H/CpnPdFESLYpm9Rh1Jnw2N l0xKZJ4XKm9aN/t6SnO67w1BjAgbz2Xdg0/uZ69prbN6TmmPDiTW8YMefQPTWVj49r docek4tCT6tr7EIlgBquCe5h17WGS3uKrql4tlVQTFGKhurNbFgAxw+9pKwi4JMz6g ctunywRPHuBZyDtvJhJnzg6FpC8YHuUDpjvFxl3rrsdn0xaVMtkFnIGWRHj1Eor9/t zdrVzXUUmZccF2XX6CRWPjeq2oOk8C/EfrVdVAWt/SEv75medwiwyio+juhxojsZ8o RwWPMW2RQE5sw== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH v4 4/6] usb: dwc2: hcd: fix possible successive vbus supply enables Reply-To: sashiko-reviews@lists.linux.dev To: "Fabrice Gasnier" Cc: linux-usb@vger.kernel.org In-Reply-To: <20261113-dwc2-low-power-fixes-stm32-v4-4-08a8c962a09e@foss.st.com> References: <20261113-dwc2-low-power-fixes-stm32-v4-0-08a8c962a09e@foss.st.com> <20261113-dwc2-low-power-fixes-stm32-v4-4-08a8c962a09e@foss.st.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Fri, 13 Nov 2026 19:49:27 +0000 X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list > Relying on HPRT0_PWR value to call dwc2_vbus_supply_init() shows some > corner case resulting in vbus enable count to increase. > As consequence, dwc2_vbus_supply_exit call done when clearing > PWR bit won't disable vbus (for example upon suspend request). >=20 > Address two case that has been seen: > - In _dwc2_hcd_start(), external VBUS supply may have already been enable= d, > before entering dwc2_hcd_reinit (e.g. the controller is in host mode, > without any device plugged). > - Upon resume from low power in case registers have been lost. In clock > gating mode PM suspend flow doesn't disable vbus while in host mode: > - dwc2_port_suspend() enters clock gating (it sets lx_state to DWC2_L2) > - _dwc2_hcd_suspend() nothing more to do as already in L2. > - _dwc2_hcd_resume() - checks HPRT0_CONNSTS. If it's not set (register > loss) it sets HPRT0_PWR and call dwc2_vbus_supply_init(). >=20 > Fix this by adding a boolean flag to balance vbus enable/disable calls > instead of relying on HPRT0_PWR value. Clean the existing checks on pwr > bit. A mutex is added as dwc2_vbus_supply_init/_exit calls can run > concurrently from hub_control and dwc2_conn_id_status_change. >=20 > Fixes: cd7cd0e6cedf ("usb: dwc2: fix unbalanced use of external vbus-supp= ly") > Cc: stable@vger.kernel.org > Signed-off-by: Fabrice Gasnier Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261113-dwc2-low-p= ower-fixes-stm32-v4-0-08a8c962a09e@foss.st.com?part=3D4