From nobody Mon Nov 25 19:37:42 2024 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (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 C34FE1F80CB; Fri, 25 Oct 2024 10:57:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729853854; cv=none; b=eLSgcpI54Ko4e4YBm4S2QL4j1lYRtdq1Ii2BYXWt1yOP6ggmbMeA69ePdlF4fVf1LfFqQ5XQbHcNJ+0PDqDVGA9Iby08mqcVKAE5+xIKbYmDjj9tgB0xqK3Ztm0L3oMFkwf/S0ct1MBBOb0TOpw4L5sKgCXQIi7N1l/9VLmIwNQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729853854; c=relaxed/simple; bh=f3+cAPfK4RNXXSnDuLv/8Vb+cYWmESyrDKzGzGUS+f0=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=ML2rtf/k+aL0Dx8Sj3+yOMRJxekszNUY1Y/Fc8s0Xyis5oZpwkm53s6mg1y+Y+a50VIenLrOw2SfJU4TAo7uzx3obP17gnBgbUj5yyPDLtzvWE1jw1W/c9IHP/TShz0z/2U3SCNpnms0orfrjXQd2xfv9R3VaMLY+DsdTsx1W3U= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=0KEa8E1l; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=cYx1aTc9; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="0KEa8E1l"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="cYx1aTc9" From: John Ogness DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1729853851; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Uqo1w8ChYQdngURCDum4RxzHCiFXSNcp0ppGWjfcIRs=; b=0KEa8E1lizdsEtz/CP98LmuxFbdk0lKDtf0vyc0eP9p9JPkwo456dzbW/B4O7vfy2W3iA5 WRvANjE9vpkAJwkw3LaykMKUJa+AWEqhRZLg1V05qTWfBnwfpb+hfFpaKSA82QK/aaqMGv yG3Mmt3q4KpHEKALOjKfM87Hvd8LBXdarnoTtY+MuMNt5n/QrVMot6UHpiIaDIvPlSVqsP 4iq1pJAQbN1hc34dbgMD4dbJSE6j69KVJ171Mrq6bYsaiRNuu7YEfnbLHOkbd/oDlQgGpC zX3FrpGRr78G2oOowVXi/ixAbQ+CM4H5WOXLNPtqPcsSo71Z30Zq84JE0HjCzQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1729853851; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Uqo1w8ChYQdngURCDum4RxzHCiFXSNcp0ppGWjfcIRs=; b=cYx1aTc9gdCNISApxi3ofM1UDkCWGROWg8TZ3+MkNPzEJa0DOKj5VFEcZB42zyFyRH4nEK FUi59G7fNy6IjPDA== To: Greg Kroah-Hartman Cc: Jiri Slaby , Petr Mladek , Sergey Senozhatsky , Steven Rostedt , Thomas Gleixner , Esben Haabendal , linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org, Andy Shevchenko , Rengarajan S , Serge Semin , Lino Sanfilippo Subject: [PATCH tty-next v3 2/6] serial: 8250: Use high-level write function for FIFO Date: Fri, 25 Oct 2024 13:03:24 +0206 Message-Id: <20241025105728.602310-3-john.ogness@linutronix.de> In-Reply-To: <20241025105728.602310-1-john.ogness@linutronix.de> References: <20241025105728.602310-1-john.ogness@linutronix.de> 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 Content-Type: text/plain; charset="utf-8" Currently serial8250_console_fifo_write() directly writes into the UART_TX register, rather than using the high-level function serial8250_console_putchar(). This is because serial8250_console_putchar() waits for the holding register to become empty. That would defeat the purpose of the FIFO code. Move the LSR_THRE waiting to a new function serial8250_console_wait_putchar() so that the FIFO code can use serial8250_console_putchar(). This will be particularly important for a follow-up commit, where output bytes are inspected to track newlines. This is only refactoring and has no functional change. Signed-off-by: John Ogness Reviewed-by: Andy Shevchenko Reviewed-by: Petr Mladek --- drivers/tty/serial/8250/8250_port.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/= 8250_port.c index adc48eeeac2b..8f7c9968ad41 100644 --- a/drivers/tty/serial/8250/8250_port.c +++ b/drivers/tty/serial/8250/8250_port.c @@ -3268,11 +3268,16 @@ EXPORT_SYMBOL_GPL(serial8250_set_defaults); #ifdef CONFIG_SERIAL_8250_CONSOLE =20 static void serial8250_console_putchar(struct uart_port *port, unsigned ch= ar ch) +{ + serial_port_out(port, UART_TX, ch); +} + +static void serial8250_console_wait_putchar(struct uart_port *port, unsign= ed char ch) { struct uart_8250_port *up =3D up_to_u8250p(port); =20 wait_for_xmitr(up, UART_LSR_THRE); - serial_port_out(port, UART_TX, ch); + serial8250_console_putchar(port, ch); } =20 /* @@ -3312,6 +3317,7 @@ static void serial8250_console_fifo_write(struct uart= _8250_port *up, { const char *end =3D s + count; unsigned int fifosize =3D up->tx_loadsz; + struct uart_port *port =3D &up->port; unsigned int tx_count =3D 0; bool cr_sent =3D false; unsigned int i; @@ -3325,10 +3331,10 @@ static void serial8250_console_fifo_write(struct ua= rt_8250_port *up, =20 for (i =3D 0; i < fifosize && s !=3D end; ++i) { if (*s =3D=3D '\n' && !cr_sent) { - serial_out(up, UART_TX, '\r'); + serial8250_console_putchar(port, '\r'); cr_sent =3D true; } else { - serial_out(up, UART_TX, *s++); + serial8250_console_putchar(port, *s++); cr_sent =3D false; } } @@ -3408,7 +3414,7 @@ void serial8250_console_write(struct uart_8250_port *= up, const char *s, if (likely(use_fifo)) serial8250_console_fifo_write(up, s, count); else - uart_console_write(port, s, count, serial8250_console_putchar); + uart_console_write(port, s, count, serial8250_console_wait_putchar); =20 /* * Finally, wait for transmitter to become empty --=20 2.39.5