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=1792639224; b=4L8kPOZJez7x06hQtc41VXYqfBuTne6iAlsGUGkPZnzpD+WJVrW23Pqqii0+hscLGGiV aWZZpAIcUp8UL4EIVGiTwkSPS+8MsbBw8RdtWBZWNTcvV/CodLEyH4u9Wh0q+Ms2IfPtp dO1OiG/Kz+CgMsmxiJnTu6L6+pJpxKKMckh2wQCGLLMfEQoJcKKb/Dy0hW9GC7uZbRMHo J+UjHCtsfSiVCjg3TAiQ4MIgfYJRvuuM3+e+Y0d98O7Vi9wi2e8Z8JokFPT0pacn68cVP hdJBo3pFMZB4Ck62hcPxeM08YJf4JttDE81oOtaWuvYxaJuSQAzFTKRJxnfXC5uBz1A== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792639224; h=Received:DKIM-Signature:Message-ID:From:Subject:Reply-To:To:Cc: In-Reply-To:References:Content-Type:Content-Transfer-Encoding:Date; bh=XmYJvXPM2C7j2KAfwMSEntIxLEXmLm3wZl5MHZU8aCI=; b=GVD4K2d1LXJV5HJDeKJCI7rB24IS/J5X0hqV8xaDPSkmiFW0MsbV6luuZBzAfNFS4TVX SBff8EznMuRE+oDzEmhKOOVyA/dM5764yqwMZYKZbrjE5XAHIQKo4lkNWcZjRo+BHTWkf gmpRDmwi4vXk66KjwVdY7Z41oQjMke/caBNfeprl6m1yvLCgR5Bh+NVyqGrK5uzwKBpLs y1JaIMzBViNwgzYkMdyRbnPiNpESIShXtUPX5fvk+IptKJrff4MmHE33LCC2OBAYUOyEL xfhHtL88csgn23YXMPT2xOoOTROYrFw1TcMCZgRw+fbEsoauH8Va9xKfZ2Hx/de5JcA== 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=F8ayY2VD; 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 A9441606A319 for ; Thu, 22 Oct 2026 03:20:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=F8ayY2VD Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0A6301F000C1; Thu, 22 Oct 2026 03:20:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792639223; bh=XmYJvXPM2C7j2KAfwMSEntIxLEXmLm3wZl5MHZU8aCI=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=F8ayY2VDjWiLyFLIiE0QGqP+EFTfX4Fbii9zzMu7+N/KhgaDxjLI9yTcjZZTYN5FU A41on6I1TPOQ1pbCE3oB2QPC188PNG6s8LQh99mER7LRccs3Q+rdOqQRnAiiFk4TMC NP5aPy+ePBSQ6RPiA/0Pmg9juZzWREEdqMR7CyNGuCJRks4UI7bsS3lV8NBKNhsZAx yywUaa50/KOVljhcfRpgu2dpu/khR3VjmKklJhRcLXbJq9UTjm8ga56mQovF8Njc1r VZ9T8EzHRLabxfNQX5MaLBVlWb6g2jvX6qr14n/vicOQnn+sHL8uk93P7cusYA57sj kpTIZZVXPxf7A== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH 2/2] tty: serial: lpuart: disable hardware flow control in lpuart32_startup() Reply-To: sashiko-reviews@lists.linux.dev To: =?utf-8?b?U2hlcnJ5IFN1biAoT1NTKQ==?= Cc: linux-serial@vger.kernel.org In-Reply-To: <20261022-b4-lpuart_rts_fix-v1-2-207f91580dee@nxp.com> References: <20261022-b4-lpuart_rts_fix-v1-0-207f91580dee@nxp.com> <20261022-b4-lpuart_rts_fix-v1-2-207f91580dee@nxp.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Thu, 22 Oct 2026 03:20:22 +0000 X-Mailing-List: linux-serial@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list > From: Sherry Sun >=20 > The RXRTSE/TXCTSE bits in UARTMODIR are configured by set_termios() > according to CRTSCTS and are left untouched by shutdown(), so they keep > their value from the previous session when the port is started again. >=20 > On open, and on resume when a tty is attached, the serial core calls > ops->startup() before set_termios(). lpuart32_startup() enables the > receiver (UARTCTRL_RE), and with RXRTSE still set from the previous > session RTS is asserted immediately. The remote side may then start > sending before set_termios() deasserts RTS again, disables TE/RE and > reprograms the baud rate, so the characters in flight are lost or > corrupted. >=20 > Clear RXRTSE/TXCTSE at the beginning of lpuart32_startup() instead. > Together with set_termios() keeping both bits masked until its last > UARTMODIR write, RTS now stays deasserted from startup() until the port > is fully configured. The flow control setting itself is still owned by > set_termios(). >=20 > Fixes: 380c966c093e ("tty: serial: fsl_lpuart: add 32-bit register interf= ace support") > Cc: stable@vger.kernel.org > Signed-off-by: Sherry Sun Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261022-b4-lpuart_= rts_fix-v1-0-207f91580dee@nxp.com?part=3D2