From patchwork Mon May 10 07:00:54 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiri Slaby X-Patchwork-Id: 434635 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C0E20C433B4 for ; Mon, 10 May 2021 07:00:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9087261432 for ; Mon, 10 May 2021 07:00:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230050AbhEJHCA (ORCPT ); Mon, 10 May 2021 03:02:00 -0400 Received: from mx2.suse.de ([195.135.220.15]:58810 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230009AbhEJHCA (ORCPT ); Mon, 10 May 2021 03:02:00 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 4901CB180; Mon, 10 May 2021 07:00:55 +0000 (UTC) From: Jiri Slaby To: gregkh@linuxfoundation.org Cc: linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org, Jiri Slaby , Andy Shevchenko , Joe Perches Subject: [PATCH v2 34/35] tty: make tty_get_byte_size available Date: Mon, 10 May 2021 09:00:54 +0200 Message-Id: <20210510070054.5397-1-jslaby@suse.cz> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210505091928.22010-35-jslaby@suse.cz> References: <20210505091928.22010-35-jslaby@suse.cz> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-serial@vger.kernel.org Many tty drivers contain code to compute bits count depending on termios cflags. So extract this code from serial core to a separate tty helper function called tty_get_byte_size. In the next patch, call to this new function will replace many copies of this code. [v2] simplified the code flow as suggested by Joe and Andy Signed-off-by: Jiri Slaby Reviewed-by: Andy Shevchenko Cc: Joe Perches --- drivers/tty/serial/serial_core.c | 30 +++-------------------- drivers/tty/tty_ioctl.c | 42 ++++++++++++++++++++++++++++++++ include/linux/tty.h | 2 ++ 3 files changed, 47 insertions(+), 27 deletions(-) diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c index d29329eb52f4..b3fc2b02a705 100644 --- a/drivers/tty/serial/serial_core.c +++ b/drivers/tty/serial/serial_core.c @@ -334,39 +334,15 @@ void uart_update_timeout(struct uart_port *port, unsigned int cflag, unsigned int baud) { - unsigned int bits; + unsigned int size; - /* byte size and parity */ - switch (cflag & CSIZE) { - case CS5: - bits = 7; - break; - case CS6: - bits = 8; - break; - case CS7: - bits = 9; - break; - default: - bits = 10; - break; /* CS8 */ - } - - if (cflag & CSTOPB) - bits++; - if (cflag & PARENB) - bits++; - - /* - * The total number of bits to be transmitted in the fifo. - */ - bits = bits * port->fifosize; + size = tty_get_byte_size(cflag, true) * port->fifosize; /* * Figure the timeout to send the above number of bits. * Add .02 seconds of slop */ - port->timeout = (HZ * bits) / baud + HZ/50; + port->timeout = (HZ * size) / baud + HZ/50; } EXPORT_SYMBOL(uart_update_timeout); diff --git a/drivers/tty/tty_ioctl.c b/drivers/tty/tty_ioctl.c index aa9ecc8be990..13acc3decd87 100644 --- a/drivers/tty/tty_ioctl.c +++ b/drivers/tty/tty_ioctl.c @@ -300,6 +300,48 @@ int tty_termios_hw_change(const struct ktermios *a, const struct ktermios *b) } EXPORT_SYMBOL(tty_termios_hw_change); +/** + * tty_get_byte_size - get size of a byte + * @cflag: termios cflag value + * @account_flags: account for start and stop bits, second stop bit (if + * set), and parity (if set) + * + * Get the size of a byte in bits depending on @cflag. Depending on + * @account_flags parameter, the result also accounts start and stop bits, + * the second stop bit, and parity bit. + */ +unsigned char tty_get_byte_size(unsigned int cflag, bool account_flags) +{ + unsigned char bits; + + switch (cflag & CSIZE) { + case CS5: + bits = 5; + break; + case CS6: + bits = 6; + break; + case CS7: + bits = 7; + break; + case CS8: + default: + bits = 8; + break; + } + + if (!account_flags) + return bits; + + if (cflag & CSTOPB) + bits++; + if (cflag & PARENB) + bits++; + + return bits + 2; +} +EXPORT_SYMBOL_GPL(tty_get_byte_size); + /** * tty_set_termios - update termios values * @tty: tty to update diff --git a/include/linux/tty.h b/include/linux/tty.h index 5cf6b2e7331b..a14b4588368c 100644 --- a/include/linux/tty.h +++ b/include/linux/tty.h @@ -496,6 +496,8 @@ static inline speed_t tty_get_baud_rate(struct tty_struct *tty) return tty_termios_baud_rate(&tty->termios); } +unsigned char tty_get_byte_size(unsigned int cflag, bool account_flags); + extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old); extern int tty_termios_hw_change(const struct ktermios *a, const struct ktermios *b); extern int tty_set_termios(struct tty_struct *tty, struct ktermios *kt);