From nobody Thu Apr 2 23:11:07 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 13ED0C433FE for ; Tue, 4 Oct 2022 10:49:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229786AbiJDKtq (ORCPT ); Tue, 4 Oct 2022 06:49:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53368 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229689AbiJDKti (ORCPT ); Tue, 4 Oct 2022 06:49:38 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DE36BB8C; Tue, 4 Oct 2022 03:49:35 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 97E70B819BB; Tue, 4 Oct 2022 10:49:34 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 196F3C43470; Tue, 4 Oct 2022 10:49:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1664880573; bh=MSUEy0p5m4xPtjCwyAZnyJ9BO8infGUnOQEUbRQhxTI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SLGEI7c63EuP5e4QAS/HpoAWRmS4U5s7BGd2DKLafgoQSmykRyFG4062sqLNg7X59 kkDNbdW4GYcdZO62xyQA10d95OZCZO3/HDyKBUom/xa0u6ebtAlw9o21pR18OOZDnC BQXQykavAJ+YvWXqM0/rY5oyQCtnRrEK+Oc2J2/MQr2EBBjBMoQ1/eNUQ78+LQJxui iOTfwsLr3+Uorc2EkWVjx4PiARhWGRDoEdL/F7yvMvV0lTGs9Ut2nxNwBYPnxRrUEG f8bpbe7RSKXQPIbtRLS+k5EiOfWuKTXgfmGVeVcJnq3FwDiioc7w/uDm3OGLLjTF0H djyOOIvAxUWPw== From: "Jiri Slaby (SUSE)" To: gregkh@linuxfoundation.org Cc: linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org, "Jiri Slaby (SUSE)" , =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= Subject: [PATCH v5 1/3] tty: serial: introduce transmit helpers Date: Tue, 4 Oct 2022 12:49:25 +0200 Message-Id: <20221004104927.14361-2-jirislaby@kernel.org> X-Mailer: git-send-email 2.37.3 In-Reply-To: <20221004104927.14361-1-jirislaby@kernel.org> References: <20221004104927.14361-1-jirislaby@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Many serial drivers do the same thing: * send x_char if set * keep sending from the xmit circular buffer until either - the loop reaches the end of the xmit buffer - TX is stopped - HW fifo is full * check for pending characters and: - wake up tty writers to fill for more data into xmit buffer - stop TX if there is nothing in the xmit buffer The only differences are: * how to write the character to the HW fifo * the check of the end condition: - is the HW fifo full? - is limit of the written characters reached? So unify the above into two helpers: * uart_port_tx_limited() -- it performs the above taking the written characters limit into account, and * uart_port_tx() -- the same as above, except it only checks the HW readiness, not the characters limit. The HW specific operations (as stated as "differences" above) are passed as arguments to the macros. They are: * tx_ready -- returns true if HW can accept more data. * put_char -- write a character to the device. * tx_done -- when the write loop is done, perform arbitrary action before potential invocation of ops->stop_tx() happens. Note that the above are macros. This means the code is generated in place and the above 3 arguments are "inlined". I.e. no added penalty by generating call instructions for every single character. Nor any indirect calls. (As in some previous versions of this patchset.) Reviewed-by: Ilpo J=C3=A4rvinen Signed-off-by: Jiri Slaby (SUSE) --- Notes: [v4] switch from helper generators to helpers similar to wait_event() [Arnd] Documentation/driver-api/serial/driver.rst | 3 + include/linux/serial_core.h | 80 ++++++++++++++++++++++ 2 files changed, 83 insertions(+) diff --git a/Documentation/driver-api/serial/driver.rst b/Documentation/dri= ver-api/serial/driver.rst index 23c6b956cd90..98d268555dcc 100644 --- a/Documentation/driver-api/serial/driver.rst +++ b/Documentation/driver-api/serial/driver.rst @@ -78,6 +78,9 @@ Other functions uart_get_lsr_info uart_handle_dcd_change uart_handle_cts_change uart_try_toggle_sysrq uart_get_console =20 +.. kernel-doc:: include/linux/serial_core.h + :identifiers: uart_port_tx_limited uart_port_tx + Other notes ----------- =20 diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h index d657f2a42a7b..dbbc4408bb19 100644 --- a/include/linux/serial_core.h +++ b/include/linux/serial_core.h @@ -664,6 +664,86 @@ struct uart_driver { =20 void uart_write_wakeup(struct uart_port *port); =20 +#define __uart_port_tx(uport, ch, tx_ready, put_char, tx_done, for_test, = \ + for_post) \ +({ \ + struct uart_port *__port =3D (uport); \ + struct circ_buf *xmit =3D &__port->state->xmit; \ + unsigned int pending; \ + \ + for (; (for_test) && (tx_ready); (for_post), __port->icount.tx++) { \ + if (__port->x_char) { \ + (ch) =3D __port->x_char; \ + (put_char); \ + __port->x_char =3D 0; \ + continue; \ + } \ + \ + if (uart_circ_empty(xmit) || uart_tx_stopped(__port)) \ + break; \ + \ + (ch) =3D xmit->buf[xmit->tail]; \ + (put_char); \ + xmit->tail =3D (xmit->tail + 1) % UART_XMIT_SIZE; \ + } \ + \ + (tx_done); \ + \ + pending =3D uart_circ_chars_pending(xmit); \ + if (pending < WAKEUP_CHARS) { \ + uart_write_wakeup(__port); \ + \ + if (pending =3D=3D 0) \ + __port->ops->stop_tx(__port); \ + } \ + \ + pending; \ +}) + +/** + * uart_port_tx_limited -- transmit helper for uart_port with count limiti= ng + * @port: uart port + * @ch: variable to store a character to be written to the HW + * @count: a limit of characters to send + * @tx_ready: can HW accept more data function + * @put_char: function to write a character + * @tx_done: function to call after the loop is done + * + * This helper transmits characters from the xmit buffer to the hardware u= sing + * @put_char(). It does so until @count characters are sent and while @tx_= ready + * evaluates to true. + * + * Returns: the number of characters in the xmit buffer when done. + * + * The expression in macro parameters shall be designed as follows: + * * **tx_ready:** should evaluate to true if the HW can accept more data= to + * be sent. This parameter can be %true, which means the HW is always r= eady. + * * **put_char:** shall write @ch to the device of @port. + * * **tx_done:** when the write loop is done, this can perform arbitrary + * action before potential invocation of ops->stop_tx() happens. If the + * driver does not need to do anything, use e.g. ({}). + * + * For all of them, @port->lock is held, interrupts are locally disabled a= nd + * the expressions must not sleep. + */ +#define uart_port_tx_limited(port, ch, count, tx_ready, put_char, tx_done)= ({ \ + unsigned int __count =3D (count); \ + __uart_port_tx(port, ch, tx_ready, put_char, tx_done, __count, \ + __count--); \ +}) + +/** + * uart_port_tx -- transmit helper for uart_port + * @port: uart port + * @ch: variable to store a character to be written to the HW + * @tx_ready: can HW accept more data function + * @put_char: function to write a character + * + * See uart_port_tx_limited() for more details. + */ +#define uart_port_tx(port, ch, tx_ready, put_char) \ + __uart_port_tx(port, ch, tx_ready, put_char, ({}), true, ({})) + /* * Baud rate helpers. */ --=20 2.37.3 From nobody Thu Apr 2 23:11:07 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B6B98C433F5 for ; Tue, 4 Oct 2022 10:49:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229750AbiJDKtz (ORCPT ); Tue, 4 Oct 2022 06:49:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53362 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229682AbiJDKtn (ORCPT ); Tue, 4 Oct 2022 06:49:43 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 129902ADD; Tue, 4 Oct 2022 03:49:40 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 44FDCB819C1; Tue, 4 Oct 2022 10:49:39 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C87FFC433D6; Tue, 4 Oct 2022 10:49:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1664880577; bh=m8tfkarc/U/e4Iyh3eMuKRiHdieKiSSYFFKUNs0aLlI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=LZsS1DYQEOogdUehVO/d65sA//M8BaO5ZBzs+CNzw5ypWSKFsCIeNza+u5VTkqVjl YZvaOaEKRaEut9+oDIMn0KVWowG3prdR6X6TDq4ozS/miGodofiRP+Rta0cd82NVmk AIQM6ZKxMiw63KokdClk5F7mHeSjlCyFMnVv1uMdaWPmKnTrpLXx0FJItF8WqBF4XX WfoFiEmGV1B0LmIt1FNlg6HZC+GFgxlxQdUK6X1QP1UOws+5MkeQN+B4akLpoYtMFb i3CWmhUCapJ8BCY2Xdz/g0awtvgm4KLVcC/2bMX8Ojq2alipQK3A87Zp2DaOAhDzC9 WRYzw04F95k+g== From: "Jiri Slaby (SUSE)" To: gregkh@linuxfoundation.org Cc: linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org, "Jiri Slaby (SUSE)" , Tobias Klauser , Richard Genoud , Nicolas Ferre , Alexandre Belloni , Claudiu Beznea , Vladimir Zapolskiy , Liviu Dudau , Sudeep Holla , Lorenzo Pieralisi , Shawn Guo , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam , NXP Linux Team , =?UTF-8?q?Andreas=20F=C3=A4rber?= , Manivannan Sadhasivam , =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= Subject: [PATCH v5 2/3] tty: serial: use uart_port_tx() helper Date: Tue, 4 Oct 2022 12:49:26 +0200 Message-Id: <20221004104927.14361-3-jirislaby@kernel.org> X-Mailer: git-send-email 2.37.3 In-Reply-To: <20221004104927.14361-1-jirislaby@kernel.org> References: <20221004104927.14361-1-jirislaby@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org uart_port_tx() is a new helper to send characters to the device. Use it in these drivers. Cc: Tobias Klauser Cc: Richard Genoud Cc: Nicolas Ferre Cc: Alexandre Belloni Cc: Claudiu Beznea Cc: Vladimir Zapolskiy Cc: Liviu Dudau Cc: Sudeep Holla Cc: Lorenzo Pieralisi Cc: Shawn Guo Cc: Sascha Hauer Cc: Pengutronix Kernel Team Cc: Fabio Estevam Cc: NXP Linux Team Cc: "Andreas F=C3=A4rber" Cc: Manivannan Sadhasivam Reviewed-by: Ilpo J=C3=A4rvinen Signed-off-by: Jiri Slaby (SUSE) --- Notes: [v5] use bool pending in mcf_tx_chars() too [Ilpo] =20 [v4] switch from DEFINE_UART_PORT_TX_HELPER() (helper generator) to uart_port_tx() (akin to wait_event()) =20 [v3] remove stray \n removal (Ilpo) drivers/tty/serial/altera_uart.c | 29 ++++------------------ drivers/tty/serial/atmel_serial.c | 28 +++++---------------- drivers/tty/serial/fsl_lpuart.c | 30 ++++------------------- drivers/tty/serial/lantiq.c | 36 +++------------------------ drivers/tty/serial/lpc32xx_hs.c | 33 +++---------------------- drivers/tty/serial/mcf.c | 34 ++++++-------------------- drivers/tty/serial/mpc52xx_uart.c | 39 +++--------------------------- drivers/tty/serial/mps2-uart.c | 26 +++----------------- drivers/tty/serial/mxs-auart.c | 32 ++++++------------------ drivers/tty/serial/owl-uart.c | 32 +++--------------------- drivers/tty/serial/sa1100.c | 34 +++----------------------- drivers/tty/serial/vt8500_serial.c | 30 +++-------------------- 12 files changed, 60 insertions(+), 323 deletions(-) diff --git a/drivers/tty/serial/altera_uart.c b/drivers/tty/serial/altera_u= art.c index 82f2790de28d..316074bb23e9 100644 --- a/drivers/tty/serial/altera_uart.c +++ b/drivers/tty/serial/altera_uart.c @@ -247,31 +247,12 @@ static void altera_uart_rx_chars(struct uart_port *po= rt) =20 static void altera_uart_tx_chars(struct uart_port *port) { - struct circ_buf *xmit =3D &port->state->xmit; - - if (port->x_char) { - /* Send special char - probably flow control */ - altera_uart_writel(port, port->x_char, ALTERA_UART_TXDATA_REG); - port->x_char =3D 0; - port->icount.tx++; - return; - } - - while (altera_uart_readl(port, ALTERA_UART_STATUS_REG) & - ALTERA_UART_STATUS_TRDY_MSK) { - if (xmit->head =3D=3D xmit->tail) - break; - altera_uart_writel(port, xmit->buf[xmit->tail], - ALTERA_UART_TXDATA_REG); - xmit->tail =3D (xmit->tail + 1) & (UART_XMIT_SIZE - 1); - port->icount.tx++; - } - - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) - uart_write_wakeup(port); + u8 ch; =20 - if (uart_circ_empty(xmit)) - altera_uart_stop_tx(port); + uart_port_tx(port, ch, + altera_uart_readl(port, ALTERA_UART_STATUS_REG) & + ALTERA_UART_STATUS_TRDY_MSK, + altera_uart_writel(port, ch, ALTERA_UART_TXDATA_REG)); } =20 static irqreturn_t altera_uart_interrupt(int irq, void *data) diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_s= erial.c index bd07f79a2df9..a6b4d30c5888 100644 --- a/drivers/tty/serial/atmel_serial.c +++ b/drivers/tty/serial/atmel_serial.c @@ -824,30 +824,14 @@ static void atmel_rx_chars(struct uart_port *port) */ static void atmel_tx_chars(struct uart_port *port) { - struct circ_buf *xmit =3D &port->state->xmit; struct atmel_uart_port *atmel_port =3D to_atmel_uart_port(port); + bool pending; + u8 ch; =20 - if (port->x_char && - (atmel_uart_readl(port, ATMEL_US_CSR) & ATMEL_US_TXRDY)) { - atmel_uart_write_char(port, port->x_char); - port->icount.tx++; - port->x_char =3D 0; - } - if (uart_circ_empty(xmit) || uart_tx_stopped(port)) - return; - - while (atmel_uart_readl(port, ATMEL_US_CSR) & ATMEL_US_TXRDY) { - atmel_uart_write_char(port, xmit->buf[xmit->tail]); - xmit->tail =3D (xmit->tail + 1) & (UART_XMIT_SIZE - 1); - port->icount.tx++; - if (uart_circ_empty(xmit)) - break; - } - - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) - uart_write_wakeup(port); - - if (!uart_circ_empty(xmit)) { + pending =3D uart_port_tx(port, ch, + atmel_uart_readl(port, ATMEL_US_CSR) & ATMEL_US_TXRDY, + atmel_uart_write_char(port, ch)); + if (pending) { /* we still have characters to transmit, so we should continue * transmitting them when TX is ready, regardless of * mode or duplexity diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuar= t.c index 67fa113f77d4..d811eda1844e 100644 --- a/drivers/tty/serial/fsl_lpuart.c +++ b/drivers/tty/serial/fsl_lpuart.c @@ -742,32 +742,12 @@ static int lpuart32_poll_get_char(struct uart_port *p= ort) =20 static inline void lpuart_transmit_buffer(struct lpuart_port *sport) { - struct circ_buf *xmit =3D &sport->port.state->xmit; - - if (sport->port.x_char) { - writeb(sport->port.x_char, sport->port.membase + UARTDR); - sport->port.icount.tx++; - sport->port.x_char =3D 0; - return; - } - - if (lpuart_stopped_or_empty(&sport->port)) { - lpuart_stop_tx(&sport->port); - return; - } - - while (!uart_circ_empty(xmit) && - (readb(sport->port.membase + UARTTCFIFO) < sport->txfifo_size)) { - writeb(xmit->buf[xmit->tail], sport->port.membase + UARTDR); - xmit->tail =3D (xmit->tail + 1) & (UART_XMIT_SIZE - 1); - sport->port.icount.tx++; - } - - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) - uart_write_wakeup(&sport->port); + struct uart_port *port =3D &sport->port; + u8 ch; =20 - if (uart_circ_empty(xmit)) - lpuart_stop_tx(&sport->port); + uart_port_tx(port, ch, + readb(port->membase + UARTTCFIFO) < sport->txfifo_size, + writeb(ch, port->membase + UARTDR)); } =20 static inline void lpuart32_transmit_buffer(struct lpuart_port *sport) diff --git a/drivers/tty/serial/lantiq.c b/drivers/tty/serial/lantiq.c index c892f3c7d1ab..a58e9277dfad 100644 --- a/drivers/tty/serial/lantiq.c +++ b/drivers/tty/serial/lantiq.c @@ -95,7 +95,6 @@ #define ASCFSTAT_TXFFLMASK 0x3F00 #define ASCFSTAT_TXFREEMASK 0x3F000000 =20 -static void lqasc_tx_chars(struct uart_port *port); static struct ltq_uart_port *lqasc_port[MAXPORTS]; static struct uart_driver lqasc_reg; =20 @@ -151,9 +150,12 @@ lqasc_start_tx(struct uart_port *port) { unsigned long flags; struct ltq_uart_port *ltq_port =3D to_ltq_uart_port(port); + u8 ch; =20 spin_lock_irqsave(<q_port->lock, flags); - lqasc_tx_chars(port); + uart_port_tx(port, ch, + lqasc_tx_ready(port), + writeb(ch, port->membase + LTQ_ASC_TBUF)); spin_unlock_irqrestore(<q_port->lock, flags); return; } @@ -226,36 +228,6 @@ lqasc_rx_chars(struct uart_port *port) return 0; } =20 -static void -lqasc_tx_chars(struct uart_port *port) -{ - struct circ_buf *xmit =3D &port->state->xmit; - if (uart_tx_stopped(port)) { - lqasc_stop_tx(port); - return; - } - - while (lqasc_tx_ready(port)) { - if (port->x_char) { - writeb(port->x_char, port->membase + LTQ_ASC_TBUF); - port->icount.tx++; - port->x_char =3D 0; - continue; - } - - if (uart_circ_empty(xmit)) - break; - - writeb(port->state->xmit.buf[port->state->xmit.tail], - port->membase + LTQ_ASC_TBUF); - xmit->tail =3D (xmit->tail + 1) & (UART_XMIT_SIZE - 1); - port->icount.tx++; - } - - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) - uart_write_wakeup(port); -} - static irqreturn_t lqasc_tx_int(int irq, void *_port) { diff --git a/drivers/tty/serial/lpc32xx_hs.c b/drivers/tty/serial/lpc32xx_h= s.c index ed47f4768338..b38fe4728c26 100644 --- a/drivers/tty/serial/lpc32xx_hs.c +++ b/drivers/tty/serial/lpc32xx_hs.c @@ -276,8 +276,6 @@ static void __serial_lpc32xx_rx(struct uart_port *port) tty_flip_buffer_push(tport); } =20 -static void serial_lpc32xx_stop_tx(struct uart_port *port); - static bool serial_lpc32xx_tx_ready(struct uart_port *port) { u32 level =3D readl(LPC32XX_HSUART_LEVEL(port->membase)); @@ -287,34 +285,11 @@ static bool serial_lpc32xx_tx_ready(struct uart_port = *port) =20 static void __serial_lpc32xx_tx(struct uart_port *port) { - struct circ_buf *xmit =3D &port->state->xmit; - - if (port->x_char) { - writel((u32)port->x_char, LPC32XX_HSUART_FIFO(port->membase)); - port->icount.tx++; - port->x_char =3D 0; - return; - } - - if (uart_circ_empty(xmit) || uart_tx_stopped(port)) - goto exit_tx; - - /* Transfer data */ - while (serial_lpc32xx_tx_ready(port)) { - writel((u32) xmit->buf[xmit->tail], - LPC32XX_HSUART_FIFO(port->membase)); - xmit->tail =3D (xmit->tail + 1) & (UART_XMIT_SIZE - 1); - port->icount.tx++; - if (uart_circ_empty(xmit)) - break; - } - - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) - uart_write_wakeup(port); + u8 ch; =20 -exit_tx: - if (uart_circ_empty(xmit)) - serial_lpc32xx_stop_tx(port); + uart_port_tx(port, ch, + serial_lpc32xx_tx_ready(port), + writel(ch, LPC32XX_HSUART_FIFO(port->membase))); } =20 static irqreturn_t serial_lpc32xx_interrupt(int irq, void *dev_id) diff --git a/drivers/tty/serial/mcf.c b/drivers/tty/serial/mcf.c index b1cd9a76dd93..3239babe12a4 100644 --- a/drivers/tty/serial/mcf.c +++ b/drivers/tty/serial/mcf.c @@ -327,34 +327,16 @@ static void mcf_rx_chars(struct mcf_uart *pp) static void mcf_tx_chars(struct mcf_uart *pp) { struct uart_port *port =3D &pp->port; - struct circ_buf *xmit =3D &port->state->xmit; - - if (port->x_char) { - /* Send special char - probably flow control */ - writeb(port->x_char, port->membase + MCFUART_UTB); - port->x_char =3D 0; - port->icount.tx++; - return; - } - - while (readb(port->membase + MCFUART_USR) & MCFUART_USR_TXREADY) { - if (uart_circ_empty(xmit)) - break; - writeb(xmit->buf[xmit->tail], port->membase + MCFUART_UTB); - xmit->tail =3D (xmit->tail + 1) & (UART_XMIT_SIZE -1); - port->icount.tx++; - } + bool pending; + u8 ch; =20 - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) - uart_write_wakeup(port); + pending =3D uart_port_tx(port, ch, + readb(port->membase + MCFUART_USR) & MCFUART_USR_TXREADY, + writeb(ch, port->membase + MCFUART_UTB)); =20 - if (uart_circ_empty(xmit)) { - mcf_stop_tx(port); - /* Disable TX to negate RTS automatically */ - if (port->rs485.flags & SER_RS485_ENABLED) - writeb(MCFUART_UCR_TXDISABLE, - port->membase + MCFUART_UCR); - } + /* Disable TX to negate RTS automatically */ + if (!pending && (port->rs485.flags & SER_RS485_ENABLED)) + writeb(MCFUART_UCR_TXDISABLE, port->membase + MCFUART_UCR); } =20 /*************************************************************************= ***/ diff --git a/drivers/tty/serial/mpc52xx_uart.c b/drivers/tty/serial/mpc52xx= _uart.c index 73362d4bc45d..384ca195e3d5 100644 --- a/drivers/tty/serial/mpc52xx_uart.c +++ b/drivers/tty/serial/mpc52xx_uart.c @@ -1428,42 +1428,11 @@ mpc52xx_uart_int_rx_chars(struct uart_port *port) static inline bool mpc52xx_uart_int_tx_chars(struct uart_port *port) { - struct circ_buf *xmit =3D &port->state->xmit; - - /* Process out of band chars */ - if (port->x_char) { - psc_ops->write_char(port, port->x_char); - port->icount.tx++; - port->x_char =3D 0; - return true; - } - - /* Nothing to do ? */ - if (uart_circ_empty(xmit) || uart_tx_stopped(port)) { - mpc52xx_uart_stop_tx(port); - return false; - } - - /* Send chars */ - while (psc_ops->raw_tx_rdy(port)) { - psc_ops->write_char(port, xmit->buf[xmit->tail]); - xmit->tail =3D (xmit->tail + 1) & (UART_XMIT_SIZE - 1); - port->icount.tx++; - if (uart_circ_empty(xmit)) - break; - } - - /* Wake up */ - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) - uart_write_wakeup(port); - - /* Maybe we're done after all */ - if (uart_circ_empty(xmit)) { - mpc52xx_uart_stop_tx(port); - return false; - } + u8 ch; =20 - return true; + return uart_port_tx(port, ch, + psc_ops->raw_tx_rdy(port), + psc_ops->write_char(port, ch)); } =20 static irqreturn_t diff --git a/drivers/tty/serial/mps2-uart.c b/drivers/tty/serial/mps2-uart.c index 2e3e6cf16817..860d161fa594 100644 --- a/drivers/tty/serial/mps2-uart.c +++ b/drivers/tty/serial/mps2-uart.c @@ -129,29 +129,11 @@ static void mps2_uart_stop_tx(struct uart_port *port) =20 static void mps2_uart_tx_chars(struct uart_port *port) { - struct circ_buf *xmit =3D &port->state->xmit; - - while (!(mps2_uart_read8(port, UARTn_STATE) & UARTn_STATE_TX_FULL)) { - if (port->x_char) { - mps2_uart_write8(port, port->x_char, UARTn_DATA); - port->x_char =3D 0; - port->icount.tx++; - continue; - } - - if (uart_circ_empty(xmit) || uart_tx_stopped(port)) - break; - - mps2_uart_write8(port, xmit->buf[xmit->tail], UARTn_DATA); - xmit->tail =3D (xmit->tail + 1) % UART_XMIT_SIZE; - port->icount.tx++; - } - - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) - uart_write_wakeup(port); + u8 ch; =20 - if (uart_circ_empty(xmit)) - mps2_uart_stop_tx(port); + uart_port_tx(port, ch, + mps2_uart_tx_empty(port), + mps2_uart_write8(port, ch, UARTn_DATA)); } =20 static void mps2_uart_start_tx(struct uart_port *port) diff --git a/drivers/tty/serial/mxs-auart.c b/drivers/tty/serial/mxs-auart.c index d21a4f3ef2fe..ef6e7bb6105c 100644 --- a/drivers/tty/serial/mxs-auart.c +++ b/drivers/tty/serial/mxs-auart.c @@ -569,6 +569,8 @@ static int mxs_auart_dma_tx(struct mxs_auart_port *s, i= nt size) static void mxs_auart_tx_chars(struct mxs_auart_port *s) { struct circ_buf *xmit =3D &s->port.state->xmit; + bool pending; + u8 ch; =20 if (auart_dma_enabled(s)) { u32 i =3D 0; @@ -603,31 +605,13 @@ static void mxs_auart_tx_chars(struct mxs_auart_port = *s) return; } =20 - - while (!(mxs_read(s, REG_STAT) & AUART_STAT_TXFF)) { - if (s->port.x_char) { - s->port.icount.tx++; - mxs_write(s->port.x_char, s, REG_DATA); - s->port.x_char =3D 0; - continue; - } - if (!uart_circ_empty(xmit) && !uart_tx_stopped(&s->port)) { - s->port.icount.tx++; - mxs_write(xmit->buf[xmit->tail], s, REG_DATA); - xmit->tail =3D (xmit->tail + 1) & (UART_XMIT_SIZE - 1); - } else - break; - } - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) - uart_write_wakeup(&s->port); - - if (uart_circ_empty(&(s->port.state->xmit))) - mxs_clr(AUART_INTR_TXIEN, s, REG_INTR); - else + pending =3D uart_port_tx(&s->port, ch, + !(mxs_read(s, REG_STAT) & AUART_STAT_TXFF), + mxs_write(ch, s, REG_DATA)); + if (pending) mxs_set(AUART_INTR_TXIEN, s, REG_INTR); - - if (uart_tx_stopped(&s->port)) - mxs_auart_stop_tx(&s->port); + else + mxs_clr(AUART_INTR_TXIEN, s, REG_INTR); } =20 static void mxs_auart_rx_char(struct mxs_auart_port *s) diff --git a/drivers/tty/serial/owl-uart.c b/drivers/tty/serial/owl-uart.c index fde39cc1145d..e99970a9437f 100644 --- a/drivers/tty/serial/owl-uart.c +++ b/drivers/tty/serial/owl-uart.c @@ -181,35 +181,11 @@ static void owl_uart_start_tx(struct uart_port *port) =20 static void owl_uart_send_chars(struct uart_port *port) { - struct circ_buf *xmit =3D &port->state->xmit; - unsigned int ch; - - if (port->x_char) { - while (!(owl_uart_read(port, OWL_UART_STAT) & OWL_UART_STAT_TFFU)) - cpu_relax(); - owl_uart_write(port, port->x_char, OWL_UART_TXDAT); - port->icount.tx++; - port->x_char =3D 0; - } - - if (uart_tx_stopped(port)) - return; - - while (!(owl_uart_read(port, OWL_UART_STAT) & OWL_UART_STAT_TFFU)) { - if (uart_circ_empty(xmit)) - break; + u8 ch; =20 - ch =3D xmit->buf[xmit->tail]; - owl_uart_write(port, ch, OWL_UART_TXDAT); - xmit->tail =3D (xmit->tail + 1) & (UART_XMIT_SIZE - 1); - port->icount.tx++; - } - - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) - uart_write_wakeup(port); - - if (uart_circ_empty(xmit)) - owl_uart_stop_tx(port); + uart_port_tx(port, ch, + !(owl_uart_read(port, OWL_UART_STAT) & OWL_UART_STAT_TFFU), + owl_uart_write(port, ch, OWL_UART_TXDAT)); } =20 static void owl_uart_receive_chars(struct uart_port *port) diff --git a/drivers/tty/serial/sa1100.c b/drivers/tty/serial/sa1100.c index dd9e3253cab4..55107bbc00ce 100644 --- a/drivers/tty/serial/sa1100.c +++ b/drivers/tty/serial/sa1100.c @@ -228,14 +228,7 @@ sa1100_rx_chars(struct sa1100_port *sport) =20 static void sa1100_tx_chars(struct sa1100_port *sport) { - struct circ_buf *xmit =3D &sport->port.state->xmit; - - if (sport->port.x_char) { - UART_PUT_CHAR(sport, sport->port.x_char); - sport->port.icount.tx++; - sport->port.x_char =3D 0; - return; - } + u8 ch; =20 /* * Check the modem control lines before @@ -243,28 +236,9 @@ static void sa1100_tx_chars(struct sa1100_port *sport) */ sa1100_mctrl_check(sport); =20 - if (uart_circ_empty(xmit) || uart_tx_stopped(&sport->port)) { - sa1100_stop_tx(&sport->port); - return; - } - - /* - * Tried using FIFO (not checking TNF) for fifo fill: - * still had the '4 bytes repeated' problem. - */ - while (UART_GET_UTSR1(sport) & UTSR1_TNF) { - UART_PUT_CHAR(sport, xmit->buf[xmit->tail]); - xmit->tail =3D (xmit->tail + 1) & (UART_XMIT_SIZE - 1); - sport->port.icount.tx++; - if (uart_circ_empty(xmit)) - break; - } - - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) - uart_write_wakeup(&sport->port); - - if (uart_circ_empty(xmit)) - sa1100_stop_tx(&sport->port); + uart_port_tx(&sport->port, ch, + UART_GET_UTSR1(sport) & UTSR1_TNF, + UART_PUT_CHAR(sport, ch)); } =20 static irqreturn_t sa1100_int(int irq, void *dev_id) diff --git a/drivers/tty/serial/vt8500_serial.c b/drivers/tty/serial/vt8500= _serial.c index 10fbdb09965f..deedb6513160 100644 --- a/drivers/tty/serial/vt8500_serial.c +++ b/drivers/tty/serial/vt8500_serial.c @@ -196,33 +196,11 @@ static unsigned int vt8500_tx_empty(struct uart_port = *port) =20 static void handle_tx(struct uart_port *port) { - struct circ_buf *xmit =3D &port->state->xmit; + u8 ch; =20 - if (port->x_char) { - writeb(port->x_char, port->membase + VT8500_TXFIFO); - port->icount.tx++; - port->x_char =3D 0; - } - if (uart_circ_empty(xmit) || uart_tx_stopped(port)) { - vt8500_stop_tx(port); - return; - } - - while (vt8500_tx_empty(port)) { - if (uart_circ_empty(xmit)) - break; - - writeb(xmit->buf[xmit->tail], port->membase + VT8500_TXFIFO); - - xmit->tail =3D (xmit->tail + 1) & (UART_XMIT_SIZE - 1); - port->icount.tx++; - } - - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) - uart_write_wakeup(port); - - if (uart_circ_empty(xmit)) - vt8500_stop_tx(port); + uart_port_tx(port, ch, + vt8500_tx_empty(port), + writeb(ch, port->membase + VT8500_TXFIFO)); } =20 static void vt8500_start_tx(struct uart_port *port) --=20 2.37.3 From nobody Thu Apr 2 23:11:07 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6A05BC433FE for ; Tue, 4 Oct 2022 10:50:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229530AbiJDKuC (ORCPT ); Tue, 4 Oct 2022 06:50:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53368 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229675AbiJDKto (ORCPT ); Tue, 4 Oct 2022 06:49:44 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EA13C6420; Tue, 4 Oct 2022 03:49:42 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 3DAC66134B; Tue, 4 Oct 2022 10:49:42 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6BAE2C4347C; Tue, 4 Oct 2022 10:49:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1664880581; bh=EiG7MLXpt/ieQf/scjf2AjsAsALEw0iDo5jOA5XLK1o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=PuVLtqtDLOT35uK/LKnFhKdO0kypUV5cjbuQpI1HoAo/jyjXpt0+wXMugbV9m+DH1 rtjsLiAd/QPE3wrlBKsAgA8c8fLOQpgmoth5DWgiQddc779ITsKE5MbOjL9jis3Gus e+zgNVycSJbIax0Fzpu4RqkALLumzUjWKLO+R421G5GgutWK7Ut7RKt5NKPKhZu/S2 BhXtJdVBlmMNHO5szSGb0i8jYIJaMtJvXSgif7/EcdNG2iKkegj7VbXe2SgmVKkcY5 Lk6y5yk4YHUikyo2kUJ77MEAzmivbFTC3NEHc5Swhicqze11ubW4qA/2Qh1Tb1NPA8 YhVI37WXg8xTA== From: "Jiri Slaby (SUSE)" To: gregkh@linuxfoundation.org Cc: linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org, "Jiri Slaby (SUSE)" , Russell King , Florian Fainelli , bcm-kernel-feedback-list@broadcom.com, =?UTF-8?q?Pali=20Roh=C3=A1r?= , Kevin Cernekee , Palmer Dabbelt , Paul Walmsley , Orson Zhai , Baolin Wang , Chunyan Zhang , Patrice Chotard , linux-riscv@lists.infradead.org Subject: [PATCH v5 3/3] tty: serial: use uart_port_tx_limited() Date: Tue, 4 Oct 2022 12:49:27 +0200 Message-Id: <20221004104927.14361-4-jirislaby@kernel.org> X-Mailer: git-send-email 2.37.3 In-Reply-To: <20221004104927.14361-1-jirislaby@kernel.org> References: <20221004104927.14361-1-jirislaby@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org uart_port_tx_limited() is a new helper to send characters to the device. Use it in these drivers. mux.c also needs to define tx_done(). But I'm not sure if the driver really wants to wait for all the characters to dismiss from the HW fifo at this code point. Hence I marked this as FIXME. Cc: Russell King Cc: Florian Fainelli Cc: bcm-kernel-feedback-list@broadcom.com Cc: "Pali Roh=C3=A1r" Cc: Kevin Cernekee Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Orson Zhai Cc: Baolin Wang Cc: Chunyan Zhang Cc: Patrice Chotard Cc: linux-riscv@lists.infradead.org Signed-off-by: Jiri Slaby (SUSE) Reviewed-by: Ilpo J=C3=A4rvinen --- Notes: [v4] switch from DEFINE_UART_PORT_TX_HELPER_LIMITED() (helper generator) to uart_port_tx_limited() (akin to wait_event()) drivers/tty/serial/21285.c | 32 +++---------------- drivers/tty/serial/altera_jtaguart.c | 36 ++++----------------- drivers/tty/serial/amba-pl010.c | 32 +++---------------- drivers/tty/serial/apbuart.c | 34 +++----------------- drivers/tty/serial/bcm63xx_uart.c | 47 ++++++--------------------- drivers/tty/serial/mux.c | 45 ++++++++------------------ drivers/tty/serial/mvebu-uart.c | 38 +++------------------- drivers/tty/serial/omap-serial.c | 32 +++---------------- drivers/tty/serial/pxa.c | 33 +++---------------- drivers/tty/serial/rp2.c | 31 ++++-------------- drivers/tty/serial/serial_txx9.c | 32 +++---------------- drivers/tty/serial/sifive.c | 31 +++--------------- drivers/tty/serial/sprd_serial.c | 33 +++---------------- drivers/tty/serial/st-asc.c | 48 +++------------------------- 14 files changed, 85 insertions(+), 419 deletions(-) diff --git a/drivers/tty/serial/21285.c b/drivers/tty/serial/21285.c index c7d34823f715..185462fd959c 100644 --- a/drivers/tty/serial/21285.c +++ b/drivers/tty/serial/21285.c @@ -154,35 +154,13 @@ static irqreturn_t serial21285_rx_chars(int irq, void= *dev_id) static irqreturn_t serial21285_tx_chars(int irq, void *dev_id) { struct uart_port *port =3D dev_id; - struct circ_buf *xmit =3D &port->state->xmit; - int count =3D 256; - - if (port->x_char) { - *CSR_UARTDR =3D port->x_char; - port->icount.tx++; - port->x_char =3D 0; - goto out; - } - if (uart_circ_empty(xmit) || uart_tx_stopped(port)) { - serial21285_stop_tx(port); - goto out; - } - - do { - *CSR_UARTDR =3D xmit->buf[xmit->tail]; - xmit->tail =3D (xmit->tail + 1) & (UART_XMIT_SIZE - 1); - port->icount.tx++; - if (uart_circ_empty(xmit)) - break; - } while (--count > 0 && !(*CSR_UARTFLG & 0x20)); - - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) - uart_write_wakeup(port); + u8 ch; =20 - if (uart_circ_empty(xmit)) - serial21285_stop_tx(port); + uart_port_tx_limited(port, ch, 256, + !(*CSR_UARTFLG & 0x20), + *CSR_UARTDR =3D ch, + ({})); =20 - out: return IRQ_HANDLED; } =20 diff --git a/drivers/tty/serial/altera_jtaguart.c b/drivers/tty/serial/alte= ra_jtaguart.c index c2d154d78e54..aa49553fac58 100644 --- a/drivers/tty/serial/altera_jtaguart.c +++ b/drivers/tty/serial/altera_jtaguart.c @@ -146,37 +146,15 @@ static void altera_jtaguart_rx_chars(struct altera_jt= aguart *pp) static void altera_jtaguart_tx_chars(struct altera_jtaguart *pp) { struct uart_port *port =3D &pp->port; - struct circ_buf *xmit =3D &port->state->xmit; - unsigned int pending, count; - - if (port->x_char) { - /* Send special char - probably flow control */ - writel(port->x_char, port->membase + ALTERA_JTAGUART_DATA_REG); - port->x_char =3D 0; - port->icount.tx++; - return; - } + unsigned int count; + u8 ch; =20 - pending =3D uart_circ_chars_pending(xmit); - if (pending > 0) { - count =3D altera_jtaguart_tx_space(port, NULL); - if (count > pending) - count =3D pending; - if (count > 0) { - pending -=3D count; - while (count--) { - writel(xmit->buf[xmit->tail], - port->membase + ALTERA_JTAGUART_DATA_REG); - xmit->tail =3D (xmit->tail + 1) & (UART_XMIT_SIZE - 1); - port->icount.tx++; - } - if (pending < WAKEUP_CHARS) - uart_write_wakeup(port); - } - } + count =3D altera_jtaguart_tx_space(port, NULL); =20 - if (pending =3D=3D 0) - altera_jtaguart_stop_tx(port); + uart_port_tx_limited(port, ch, count, + true, + writel(ch, port->membase + ALTERA_JTAGUART_DATA_REG), + ({})); } =20 static irqreturn_t altera_jtaguart_interrupt(int irq, void *data) diff --git a/drivers/tty/serial/amba-pl010.c b/drivers/tty/serial/amba-pl01= 0.c index af27fb8ec145..a98fae2ca422 100644 --- a/drivers/tty/serial/amba-pl010.c +++ b/drivers/tty/serial/amba-pl010.c @@ -164,34 +164,12 @@ static void pl010_rx_chars(struct uart_port *port) =20 static void pl010_tx_chars(struct uart_port *port) { - struct circ_buf *xmit =3D &port->state->xmit; - int count; + u8 ch; =20 - if (port->x_char) { - writel(port->x_char, port->membase + UART01x_DR); - port->icount.tx++; - port->x_char =3D 0; - return; - } - if (uart_circ_empty(xmit) || uart_tx_stopped(port)) { - pl010_stop_tx(port); - return; - } - - count =3D port->fifosize >> 1; - do { - writel(xmit->buf[xmit->tail], port->membase + UART01x_DR); - xmit->tail =3D (xmit->tail + 1) & (UART_XMIT_SIZE - 1); - port->icount.tx++; - if (uart_circ_empty(xmit)) - break; - } while (--count > 0); - - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) - uart_write_wakeup(port); - - if (uart_circ_empty(xmit)) - pl010_stop_tx(port); + uart_port_tx_limited(port, ch, port->fifosize >> 1, + true, + writel(ch, port->membase + UART01x_DR), + ({})); } =20 static void pl010_modem_status(struct uart_amba_port *uap) diff --git a/drivers/tty/serial/apbuart.c b/drivers/tty/serial/apbuart.c index 450f4edfda0f..915ee4b0d594 100644 --- a/drivers/tty/serial/apbuart.c +++ b/drivers/tty/serial/apbuart.c @@ -122,36 +122,12 @@ static void apbuart_rx_chars(struct uart_port *port) =20 static void apbuart_tx_chars(struct uart_port *port) { - struct circ_buf *xmit =3D &port->state->xmit; - int count; - - if (port->x_char) { - UART_PUT_CHAR(port, port->x_char); - port->icount.tx++; - port->x_char =3D 0; - return; - } - - if (uart_circ_empty(xmit) || uart_tx_stopped(port)) { - apbuart_stop_tx(port); - return; - } - - /* amba: fill FIFO */ - count =3D port->fifosize >> 1; - do { - UART_PUT_CHAR(port, xmit->buf[xmit->tail]); - xmit->tail =3D (xmit->tail + 1) & (UART_XMIT_SIZE - 1); - port->icount.tx++; - if (uart_circ_empty(xmit)) - break; - } while (--count > 0); - - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) - uart_write_wakeup(port); + u8 ch; =20 - if (uart_circ_empty(xmit)) - apbuart_stop_tx(port); + uart_port_tx_limited(port, ch, port->fifosize >> 1, + true, + UART_PUT_CHAR(port, ch), + ({})); } =20 static irqreturn_t apbuart_int(int irq, void *dev_id) diff --git a/drivers/tty/serial/bcm63xx_uart.c b/drivers/tty/serial/bcm63xx= _uart.c index 5d9737c2d1f2..62bc7244dc67 100644 --- a/drivers/tty/serial/bcm63xx_uart.c +++ b/drivers/tty/serial/bcm63xx_uart.c @@ -303,53 +303,24 @@ static void bcm_uart_do_rx(struct uart_port *port) */ static void bcm_uart_do_tx(struct uart_port *port) { - struct circ_buf *xmit; - unsigned int val, max_count; - - if (port->x_char) { - bcm_uart_writel(port, port->x_char, UART_FIFO_REG); - port->icount.tx++; - port->x_char =3D 0; - return; - } - - if (uart_tx_stopped(port)) { - bcm_uart_stop_tx(port); - return; - } - - xmit =3D &port->state->xmit; - if (uart_circ_empty(xmit)) - goto txq_empty; + unsigned int val; + bool pending; + u8 ch; =20 val =3D bcm_uart_readl(port, UART_MCTL_REG); val =3D (val & UART_MCTL_TXFIFOFILL_MASK) >> UART_MCTL_TXFIFOFILL_SHIFT; - max_count =3D port->fifosize - val; - - while (max_count--) { - unsigned int c; =20 - c =3D xmit->buf[xmit->tail]; - bcm_uart_writel(port, c, UART_FIFO_REG); - xmit->tail =3D (xmit->tail + 1) & (UART_XMIT_SIZE - 1); - port->icount.tx++; - if (uart_circ_empty(xmit)) - break; - } - - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) - uart_write_wakeup(port); - - if (uart_circ_empty(xmit)) - goto txq_empty; - return; + pending =3D uart_port_tx_limited(port, ch, port->fifosize - val, + true, + bcm_uart_writel(port, ch, UART_FIFO_REG), + ({})); + if (pending) + return; =20 -txq_empty: /* nothing to send, disable transmit interrupt */ val =3D bcm_uart_readl(port, UART_IR_REG); val &=3D ~UART_TX_INT_MASK; bcm_uart_writel(port, val, UART_IR_REG); - return; } =20 /* diff --git a/drivers/tty/serial/mux.c b/drivers/tty/serial/mux.c index ed0e763f622a..85ce1e9af44a 100644 --- a/drivers/tty/serial/mux.c +++ b/drivers/tty/serial/mux.c @@ -171,6 +171,13 @@ static void mux_break_ctl(struct uart_port *port, int = break_state) { } =20 +static void mux_tx_done(struct uart_port *port) +{ + /* FIXME js: really needs to wait? */ + while (UART_GET_FIFO_CNT(port)) + udelay(1); +} + /** * mux_write - Write chars to the mux fifo. * @port: Ptr to the uart_port. @@ -180,39 +187,13 @@ static void mux_break_ctl(struct uart_port *port, int= break_state) */ static void mux_write(struct uart_port *port) { - int count; - struct circ_buf *xmit =3D &port->state->xmit; - - if(port->x_char) { - UART_PUT_CHAR(port, port->x_char); - port->icount.tx++; - port->x_char =3D 0; - return; - } - - if(uart_circ_empty(xmit) || uart_tx_stopped(port)) { - mux_stop_tx(port); - return; - } - - count =3D (port->fifosize) - UART_GET_FIFO_CNT(port); - do { - UART_PUT_CHAR(port, xmit->buf[xmit->tail]); - xmit->tail =3D (xmit->tail + 1) & (UART_XMIT_SIZE - 1); - port->icount.tx++; - if(uart_circ_empty(xmit)) - break; - - } while(--count > 0); - - while(UART_GET_FIFO_CNT(port))=20 - udelay(1); - - if(uart_circ_chars_pending(xmit) < WAKEUP_CHARS) - uart_write_wakeup(port); + u8 ch; =20 - if (uart_circ_empty(xmit)) - mux_stop_tx(port); + uart_port_tx_limited(port, ch, + port->fifosize - UART_GET_FIFO_CNT(port), + true, + UART_PUT_CHAR(port, ch), + mux_tx_done(port)); } =20 /** diff --git a/drivers/tty/serial/mvebu-uart.c b/drivers/tty/serial/mvebu-uar= t.c index ba16e1da6bd3..7b566404cb33 100644 --- a/drivers/tty/serial/mvebu-uart.c +++ b/drivers/tty/serial/mvebu-uart.c @@ -335,40 +335,12 @@ static void mvebu_uart_rx_chars(struct uart_port *por= t, unsigned int status) =20 static void mvebu_uart_tx_chars(struct uart_port *port, unsigned int statu= s) { - struct circ_buf *xmit =3D &port->state->xmit; - unsigned int count; - unsigned int st; - - if (port->x_char) { - writel(port->x_char, port->membase + UART_TSH(port)); - port->icount.tx++; - port->x_char =3D 0; - return; - } - - if (uart_circ_empty(xmit) || uart_tx_stopped(port)) { - mvebu_uart_stop_tx(port); - return; - } - - for (count =3D 0; count < port->fifosize; count++) { - writel(xmit->buf[xmit->tail], port->membase + UART_TSH(port)); - xmit->tail =3D (xmit->tail + 1) & (UART_XMIT_SIZE - 1); - port->icount.tx++; - - if (uart_circ_empty(xmit)) - break; - - st =3D readl(port->membase + UART_STAT); - if (st & STAT_TX_FIFO_FUL) - break; - } - - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) - uart_write_wakeup(port); + u8 ch; =20 - if (uart_circ_empty(xmit)) - mvebu_uart_stop_tx(port); + uart_port_tx_limited(port, ch, port->fifosize, + !(readl(port->membase + UART_STAT) & STAT_TX_FIFO_FUL), + writel(ch, port->membase + UART_TSH(port)), + ({})); } =20 static irqreturn_t mvebu_uart_isr(int irq, void *dev_id) diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-ser= ial.c index 7d0d2718ef59..82d35dbbfa6c 100644 --- a/drivers/tty/serial/omap-serial.c +++ b/drivers/tty/serial/omap-serial.c @@ -347,34 +347,12 @@ static void serial_omap_put_char(struct uart_omap_por= t *up, unsigned char ch) =20 static void transmit_chars(struct uart_omap_port *up, unsigned int lsr) { - struct circ_buf *xmit =3D &up->port.state->xmit; - int count; + u8 ch; =20 - if (up->port.x_char) { - serial_omap_put_char(up, up->port.x_char); - up->port.icount.tx++; - up->port.x_char =3D 0; - return; - } - if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) { - serial_omap_stop_tx(&up->port); - return; - } - count =3D up->port.fifosize / 4; - do { - serial_omap_put_char(up, xmit->buf[xmit->tail]); - xmit->tail =3D (xmit->tail + 1) & (UART_XMIT_SIZE - 1); - up->port.icount.tx++; - - if (uart_circ_empty(xmit)) - break; - } while (--count > 0); - - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) - uart_write_wakeup(&up->port); - - if (uart_circ_empty(xmit)) - serial_omap_stop_tx(&up->port); + uart_port_tx_limited(&up->port, ch, up->port.fifosize / 4, + true, + serial_omap_put_char(up, ch), + ({})); } =20 static inline void serial_omap_enable_ier_thri(struct uart_omap_port *up) diff --git a/drivers/tty/serial/pxa.c b/drivers/tty/serial/pxa.c index 2d25231fad84..444fa4b654ac 100644 --- a/drivers/tty/serial/pxa.c +++ b/drivers/tty/serial/pxa.c @@ -174,35 +174,12 @@ static inline void receive_chars(struct uart_pxa_port= *up, int *status) =20 static void transmit_chars(struct uart_pxa_port *up) { - struct circ_buf *xmit =3D &up->port.state->xmit; - int count; + u8 ch; =20 - if (up->port.x_char) { - serial_out(up, UART_TX, up->port.x_char); - up->port.icount.tx++; - up->port.x_char =3D 0; - return; - } - if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) { - serial_pxa_stop_tx(&up->port); - return; - } - - count =3D up->port.fifosize / 2; - do { - serial_out(up, UART_TX, xmit->buf[xmit->tail]); - xmit->tail =3D (xmit->tail + 1) & (UART_XMIT_SIZE - 1); - up->port.icount.tx++; - if (uart_circ_empty(xmit)) - break; - } while (--count > 0); - - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) - uart_write_wakeup(&up->port); - - - if (uart_circ_empty(xmit)) - serial_pxa_stop_tx(&up->port); + uart_port_tx_limited(&up->port, ch, up->port.fifosize / 2, + true, + serial_out(up, UART_TX, ch), + ({})); } =20 static void serial_pxa_start_tx(struct uart_port *port) diff --git a/drivers/tty/serial/rp2.c b/drivers/tty/serial/rp2.c index b81afb06f1f4..749b873a5d99 100644 --- a/drivers/tty/serial/rp2.c +++ b/drivers/tty/serial/rp2.c @@ -427,32 +427,13 @@ static void rp2_rx_chars(struct rp2_uart_port *up) =20 static void rp2_tx_chars(struct rp2_uart_port *up) { - u16 max_tx =3D FIFO_SIZE - readw(up->base + RP2_TX_FIFO_COUNT); - struct circ_buf *xmit =3D &up->port.state->xmit; + u8 ch; =20 - if (uart_tx_stopped(&up->port)) { - rp2_uart_stop_tx(&up->port); - return; - } - - for (; max_tx !=3D 0; max_tx--) { - if (up->port.x_char) { - writeb(up->port.x_char, up->base + RP2_DATA_BYTE); - up->port.x_char =3D 0; - up->port.icount.tx++; - continue; - } - if (uart_circ_empty(xmit)) { - rp2_uart_stop_tx(&up->port); - break; - } - writeb(xmit->buf[xmit->tail], up->base + RP2_DATA_BYTE); - xmit->tail =3D (xmit->tail + 1) & (UART_XMIT_SIZE - 1); - up->port.icount.tx++; - } - - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) - uart_write_wakeup(&up->port); + uart_port_tx_limited(&up->port, ch, + FIFO_SIZE - readw(up->base + RP2_TX_FIFO_COUNT), + true, + writeb(ch, up->base + RP2_DATA_BYTE), + ({})); } =20 static void rp2_ch_interrupt(struct rp2_uart_port *up) diff --git a/drivers/tty/serial/serial_txx9.c b/drivers/tty/serial/serial_t= xx9.c index e12f1dc18c38..eab387b01e36 100644 --- a/drivers/tty/serial/serial_txx9.c +++ b/drivers/tty/serial/serial_txx9.c @@ -321,34 +321,12 @@ receive_chars(struct uart_port *up, unsigned int *sta= tus) =20 static inline void transmit_chars(struct uart_port *up) { - struct circ_buf *xmit =3D &up->state->xmit; - int count; + u8 ch; =20 - if (up->x_char) { - sio_out(up, TXX9_SITFIFO, up->x_char); - up->icount.tx++; - up->x_char =3D 0; - return; - } - if (uart_circ_empty(xmit) || uart_tx_stopped(up)) { - serial_txx9_stop_tx(up); - return; - } - - count =3D TXX9_SIO_TX_FIFO; - do { - sio_out(up, TXX9_SITFIFO, xmit->buf[xmit->tail]); - xmit->tail =3D (xmit->tail + 1) & (UART_XMIT_SIZE - 1); - up->icount.tx++; - if (uart_circ_empty(xmit)) - break; - } while (--count > 0); - - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) - uart_write_wakeup(up); - - if (uart_circ_empty(xmit)) - serial_txx9_stop_tx(up); + uart_port_tx_limited(up, ch, TXX9_SIO_TX_FIFO, + true, + sio_out(up, TXX9_SITFIFO, ch), + ({})); } =20 static irqreturn_t serial_txx9_interrupt(int irq, void *dev_id) diff --git a/drivers/tty/serial/sifive.c b/drivers/tty/serial/sifive.c index 7fb6760b5c37..1f565a216e74 100644 --- a/drivers/tty/serial/sifive.c +++ b/drivers/tty/serial/sifive.c @@ -288,33 +288,12 @@ static void __ssp_transmit_char(struct sifive_serial_= port *ssp, int ch) */ static void __ssp_transmit_chars(struct sifive_serial_port *ssp) { - struct circ_buf *xmit =3D &ssp->port.state->xmit; - int count; - - if (ssp->port.x_char) { - __ssp_transmit_char(ssp, ssp->port.x_char); - ssp->port.icount.tx++; - ssp->port.x_char =3D 0; - return; - } - if (uart_circ_empty(xmit) || uart_tx_stopped(&ssp->port)) { - sifive_serial_stop_tx(&ssp->port); - return; - } - count =3D SIFIVE_TX_FIFO_DEPTH; - do { - __ssp_transmit_char(ssp, xmit->buf[xmit->tail]); - xmit->tail =3D (xmit->tail + 1) & (UART_XMIT_SIZE - 1); - ssp->port.icount.tx++; - if (uart_circ_empty(xmit)) - break; - } while (--count > 0); - - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) - uart_write_wakeup(&ssp->port); + u8 ch; =20 - if (uart_circ_empty(xmit)) - sifive_serial_stop_tx(&ssp->port); + uart_port_tx_limited(&ssp->port, ch, SIFIVE_TX_FIFO_DEPTH, + true, + __ssp_transmit_char(ssp, ch), + ({})); } =20 /** diff --git a/drivers/tty/serial/sprd_serial.c b/drivers/tty/serial/sprd_ser= ial.c index 342a87967631..3f34f7bb7700 100644 --- a/drivers/tty/serial/sprd_serial.c +++ b/drivers/tty/serial/sprd_serial.c @@ -626,35 +626,12 @@ static inline void sprd_rx(struct uart_port *port) =20 static inline void sprd_tx(struct uart_port *port) { - struct circ_buf *xmit =3D &port->state->xmit; - int count; - - if (port->x_char) { - serial_out(port, SPRD_TXD, port->x_char); - port->icount.tx++; - port->x_char =3D 0; - return; - } - - if (uart_circ_empty(xmit) || uart_tx_stopped(port)) { - sprd_stop_tx(port); - return; - } - - count =3D THLD_TX_EMPTY; - do { - serial_out(port, SPRD_TXD, xmit->buf[xmit->tail]); - xmit->tail =3D (xmit->tail + 1) & (UART_XMIT_SIZE - 1); - port->icount.tx++; - if (uart_circ_empty(xmit)) - break; - } while (--count > 0); - - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) - uart_write_wakeup(port); + u8 ch; =20 - if (uart_circ_empty(xmit)) - sprd_stop_tx(port); + uart_port_tx_limited(port, ch, THLD_TX_EMPTY, + true, + serial_out(port, SPRD_TXD, ch), + ({})); } =20 /* this handles the interrupt from one port */ diff --git a/drivers/tty/serial/st-asc.c b/drivers/tty/serial/st-asc.c index fcecea689a0d..5215e6910f68 100644 --- a/drivers/tty/serial/st-asc.c +++ b/drivers/tty/serial/st-asc.c @@ -237,50 +237,12 @@ static inline unsigned asc_hw_txroom(struct uart_port= *port) */ static void asc_transmit_chars(struct uart_port *port) { - struct circ_buf *xmit =3D &port->state->xmit; - int txroom; - unsigned char c; - - txroom =3D asc_hw_txroom(port); - - if ((txroom !=3D 0) && port->x_char) { - c =3D port->x_char; - port->x_char =3D 0; - asc_out(port, ASC_TXBUF, c); - port->icount.tx++; - txroom =3D asc_hw_txroom(port); - } - - if (uart_tx_stopped(port)) { - /* - * We should try and stop the hardware here, but I - * don't think the ASC has any way to do that. - */ - asc_disable_tx_interrupts(port); - return; - } - - if (uart_circ_empty(xmit)) { - asc_disable_tx_interrupts(port); - return; - } - - if (txroom =3D=3D 0) - return; - - do { - c =3D xmit->buf[xmit->tail]; - xmit->tail =3D (xmit->tail + 1) & (UART_XMIT_SIZE - 1); - asc_out(port, ASC_TXBUF, c); - port->icount.tx++; - txroom--; - } while ((txroom > 0) && (!uart_circ_empty(xmit))); - - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) - uart_write_wakeup(port); + u8 ch; =20 - if (uart_circ_empty(xmit)) - asc_disable_tx_interrupts(port); + uart_port_tx_limited(port, ch, asc_hw_txroom(port), + true, + asc_out(port, ASC_TXBUF, ch), + ({})); } =20 static void asc_receive_chars(struct uart_port *port) --=20 2.37.3