From patchwork Sat Oct 6 12:44:06 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Russell King X-Patchwork-Id: 1557661 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) by patchwork1.kernel.org (Postfix) with ESMTP id A7ABE3FD56 for ; Sat, 6 Oct 2012 13:00:20 +0000 (UTC) Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1TKTwX-0007Mg-Bc; Sat, 06 Oct 2012 12:57:22 +0000 Received: from [2002:4e20:1eda::1] (helo=caramon.arm.linux.org.uk) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1TKTjo-0003NM-JR for linux-arm-kernel@lists.infradead.org; Sat, 06 Oct 2012 12:44:13 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=arm.linux.org.uk; s=caramon; h=Date:Sender:Message-Id:Subject:Cc:To:From:References:In-Reply-To; bh=ZR2wbjqB9wjLeuUT8KhchI0HEywANKe6TrL8AyK6NlI=; b=lmKprqvH9h1KkoLbSGAzVKVBC492FSjYwfYtvdowtiV4Xdl7pzU9fUtDBByNjJk7XdTX7DEfyAWNd4tjpb4uxnqGuHYbLy1ypFeX9/saS7rOv8rO5rGHXebjmKLtLkWKB5YlC5DLgFYU8y35veaSex7zOUmwzGlfPoeinW2bWB4=; Received: from e0022681537dd.dyn.arm.linux.org.uk ([2002:4e20:1eda:1:222:68ff:fe15:37dd]:39606 helo=rmk-PC.arm.linux.org.uk) by caramon.arm.linux.org.uk with esmtpsa (TLSv1:AES256-SHA:256) (Exim 4.76) (envelope-from ) id 1TKTji-000894-Mc; Sat, 06 Oct 2012 13:44:06 +0100 Received: from rmk by rmk-PC.arm.linux.org.uk with local (Exim 4.76) (envelope-from ) id 1TKTji-0002nO-5K; Sat, 06 Oct 2012 13:44:06 +0100 In-Reply-To: <20121006123803.GD15246@n2100.arm.linux.org.uk> References: <20121006123803.GD15246@n2100.arm.linux.org.uk> From: Russell King To: Tony Lindgren , Alan Cox , Greg Kroah-Hartman Subject: [RFC 15/24] SERIAL: omap: don't read back LCR/MCR/EFR Message-Id: Date: Sat, 06 Oct 2012 13:44:06 +0100 X-Bad-Reply: References and In-Reply-To but no 'Re:' in Subject. X-Spam-Note: CRM114 invocation failed X-Spam-Score: -1.2 (-) X-Spam-Report: SpamAssassin version 3.3.2 on merlin.infradead.org summary: Content analysis details: (-1.2 points) pts rule name description ---- ---------------------- -------------------------------------------------- -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature 0.8 RDNS_NONE Delivered to internal network by a host with no rDNS X-Mailman-Approved-At: Sat, 06 Oct 2012 08:53:04 -0400 Cc: linux-omap@vger.kernel.org, linux-serial@vger.kernel.org, linux-arm-kernel@lists.infradead.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: linux-arm-kernel-bounces@lists.infradead.org Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org There's really no reason to read back these registers while setting the termios modes, provided we keep our cached copies up to date. Remove these readbacks. This has the benefit that we know that the EFR_ECB and MCR_TCRTLR bits will always be clear, so we don't need to keep masking these bits throughout the code. Signed-off-by: Russell King --- drivers/tty/serial/omap-serial.c | 13 ++++++------- 1 files changed, 6 insertions(+), 7 deletions(-) diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c index b6f8b88..70c9661 100644 --- a/drivers/tty/serial/omap-serial.c +++ b/drivers/tty/serial/omap-serial.c @@ -885,8 +885,11 @@ serial_omap_set_termios(struct uart_port *port, struct ktermios *termios, /* Enable AUTORTS and AUTOCTS */ up->efr |= UART_EFR_CTS | UART_EFR_RTS; + /* Ensure MCR RTS is asserted */ + up->mcr |= UART_MCR_RTS; + /* Disable access to TCR/TLR */ - serial_out(up, UART_MCR, up->mcr | UART_MCR_RTS); + serial_out(up, UART_MCR, up->mcr); serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); serial_out(up, UART_EFR, up->efr); serial_out(up, UART_LCR, cval); @@ -900,10 +903,8 @@ serial_omap_set_termios(struct uart_port *port, struct ktermios *termios, } /* Software Flow Control Configuration */ - up->lcr = serial_in(up, UART_LCR); serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); - up->efr = serial_in(up, UART_EFR); - serial_out(up, UART_EFR, up->efr & ~UART_EFR_ECB); + serial_out(up, UART_EFR, up->efr); serial_out(up, UART_XON1, termios->c_cc[VSTART]); serial_out(up, UART_XOFF1, termios->c_cc[VSTOP]); @@ -930,8 +931,6 @@ serial_omap_set_termios(struct uart_port *port, struct ktermios *termios, serial_out(up, UART_EFR, up->efr | UART_EFR_ECB); serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A); - up->mcr = serial_in(up, UART_MCR); - /* * IXANY Flag: * Enable any character to restart output. @@ -947,7 +946,7 @@ serial_omap_set_termios(struct uart_port *port, struct ktermios *termios, serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG); serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A); - serial_out(up, UART_MCR, up->mcr & ~UART_MCR_TCRTLR); + serial_out(up, UART_MCR, up->mcr); serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); serial_out(up, UART_EFR, up->efr); serial_out(up, UART_LCR, up->lcr);