From patchwork Tue May 12 12:40:02 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lukas Wunner X-Patchwork-Id: 213992 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=-6.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED 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 DEF4FC54E4A for ; Tue, 12 May 2020 12:44:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BB5F020674 for ; Tue, 12 May 2020 12:44:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729436AbgELMos (ORCPT ); Tue, 12 May 2020 08:44:48 -0400 Received: from mailout2.hostsharing.net ([83.223.78.233]:56311 "EHLO mailout2.hostsharing.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727783AbgELMor (ORCPT ); Tue, 12 May 2020 08:44:47 -0400 Received: from h08.hostsharing.net (h08.hostsharing.net [83.223.95.28]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "*.hostsharing.net", Issuer "COMODO RSA Domain Validation Secure Server CA" (not verified)) by mailout2.hostsharing.net (Postfix) with ESMTPS id 87C6F1037031D; Tue, 12 May 2020 14:44:45 +0200 (CEST) Received: from localhost (unknown [87.130.102.138]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by h08.hostsharing.net (Postfix) with ESMTPSA id 49227627549D; Tue, 12 May 2020 14:44:45 +0200 (CEST) X-Mailbox-Line: From 271e814af4b0db3bffbbb74abf2b46b75add4516 Mon Sep 17 00:00:00 2001 Message-Id: <271e814af4b0db3bffbbb74abf2b46b75add4516.1589285873.git.lukas@wunner.de> In-Reply-To: References: From: Lukas Wunner Date: Tue, 12 May 2020 14:40:02 +0200 Subject: [PATCH v2 2/4] serial: Allow uart_get_rs485_mode() to return errno To: Greg Kroah-Hartman , Jiri Slaby Cc: "Matwey V. Kornilov" , Giulio Benetti , Heiko Stuebner , Andy Shevchenko , Christoph Muellner , linux-serial@vger.kernel.org Sender: linux-serial-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-serial@vger.kernel.org We're about to amend uart_get_rs485_mode() to support a GPIO pin for rs485 bus termination. Retrieving the GPIO descriptor may fail, so allow uart_get_rs485_mode() to return an errno and change all callers to check for failure. The GPIO descriptor is going to be stored in struct uart_port. Pass that struct to uart_get_rs485_mode() in lieu of a struct device and struct serial_rs485, both of which are directly accessible from struct uart_port. A few drivers call uart_get_rs485_mode() before setting the struct device pointer in struct uart_port. Shuffle those calls around where necessary. [Heiko Stuebner did the ar933x_uart.c portion, hence his Signed-off-by.] Signed-off-by: Heiko Stuebner Signed-off-by: Lukas Wunner --- drivers/tty/serial/8250/8250_core.c | 4 +++- drivers/tty/serial/ar933x_uart.c | 6 ++++-- drivers/tty/serial/atmel_serial.c | 6 ++++-- drivers/tty/serial/fsl_lpuart.c | 5 ++++- drivers/tty/serial/imx.c | 6 +++++- drivers/tty/serial/omap-serial.c | 4 +++- drivers/tty/serial/serial_core.c | 6 +++++- drivers/tty/serial/stm32-usart.c | 8 ++++---- include/linux/serial_core.h | 2 +- 9 files changed, 33 insertions(+), 14 deletions(-) diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c index 9548d3f8fc8e..fc118f649887 100644 --- a/drivers/tty/serial/8250/8250_core.c +++ b/drivers/tty/serial/8250/8250_core.c @@ -1026,7 +1026,9 @@ int serial8250_register_8250_port(struct uart_8250_port *up) if (up->port.dev) { uart->port.dev = up->port.dev; - uart_get_rs485_mode(uart->port.dev, &uart->port.rs485); + ret = uart_get_rs485_mode(&uart->port); + if (ret) + goto err; } if (up->port.flags & UPF_FIXED_TYPE) diff --git a/drivers/tty/serial/ar933x_uart.c b/drivers/tty/serial/ar933x_uart.c index 7e7f1398019f..0c80a79d7442 100644 --- a/drivers/tty/serial/ar933x_uart.c +++ b/drivers/tty/serial/ar933x_uart.c @@ -766,8 +766,6 @@ static int ar933x_uart_probe(struct platform_device *pdev) goto err_disable_clk; } - uart_get_rs485_mode(&pdev->dev, &port->rs485); - port->mapbase = mem_res->start; port->line = id; port->irq = irq_res->start; @@ -786,6 +784,10 @@ static int ar933x_uart_probe(struct platform_device *pdev) baud = ar933x_uart_get_baud(port->uartclk, 0, AR933X_UART_MAX_STEP); up->max_baud = min_t(unsigned int, baud, AR933X_UART_MAX_BAUD); + ret = uart_get_rs485_mode(port); + if (ret) + goto err_disable_clk; + up->gpios = mctrl_gpio_init(port, 0); if (IS_ERR(up->gpios) && PTR_ERR(up->gpios) != -ENOSYS) return PTR_ERR(up->gpios); diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c index 8d7080efad9b..e43471b33710 100644 --- a/drivers/tty/serial/atmel_serial.c +++ b/drivers/tty/serial/atmel_serial.c @@ -2491,8 +2491,6 @@ static int atmel_init_port(struct atmel_uart_port *atmel_port, atmel_init_property(atmel_port, pdev); atmel_set_ops(port); - uart_get_rs485_mode(&mpdev->dev, &port->rs485); - port->iotype = UPIO_MEM; port->flags = UPF_BOOT_AUTOCONF | UPF_IOREMAP; port->ops = &atmel_pops; @@ -2506,6 +2504,10 @@ static int atmel_init_port(struct atmel_uart_port *atmel_port, memset(&atmel_port->rx_ring, 0, sizeof(atmel_port->rx_ring)); + ret = uart_get_rs485_mode(port); + if (ret) + return ret; + /* for console, the clock could already be configured */ if (!atmel_port->clk) { atmel_port->clk = clk_get(&mpdev->dev, "usart"); diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c index 6a9909e56449..029324c77cd7 100644 --- a/drivers/tty/serial/fsl_lpuart.c +++ b/drivers/tty/serial/fsl_lpuart.c @@ -2619,7 +2619,9 @@ static int lpuart_probe(struct platform_device *pdev) if (ret) goto failed_attach_port; - uart_get_rs485_mode(&pdev->dev, &sport->port.rs485); + ret = uart_get_rs485_mode(&sport->port); + if (ret) + goto failed_get_rs485; if (sport->port.rs485.flags & SER_RS485_RX_DURING_TX) dev_err(&pdev->dev, "driver doesn't support RX during TX\n"); @@ -2632,6 +2634,7 @@ static int lpuart_probe(struct platform_device *pdev) return 0; +failed_get_rs485: failed_attach_port: failed_irq_request: lpuart_disable_clks(sport); diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index f4d68109bc8b..91f3910d6c44 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -2302,7 +2302,11 @@ static int imx_uart_probe(struct platform_device *pdev) sport->ucr4 = readl(sport->port.membase + UCR4); sport->ufcr = readl(sport->port.membase + UFCR); - uart_get_rs485_mode(&pdev->dev, &sport->port.rs485); + ret = uart_get_rs485_mode(&sport->port); + if (ret) { + clk_disable_unprepare(sport->clk_ipg); + return ret; + } if (sport->port.rs485.flags & SER_RS485_ENABLED && (!sport->have_rtscts && !sport->have_rtsgpio)) diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c index c71c1a2266dc..8573fc9cb0cd 100644 --- a/drivers/tty/serial/omap-serial.c +++ b/drivers/tty/serial/omap-serial.c @@ -1608,7 +1608,9 @@ static int serial_omap_probe_rs485(struct uart_omap_port *up, if (!np) return 0; - uart_get_rs485_mode(up->dev, rs485conf); + ret = uart_get_rs485_mode(&up->port); + if (ret) + return ret; if (of_property_read_bool(np, "rs485-rts-active-high")) { rs485conf->flags |= SER_RS485_RTS_ON_SEND; diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c index 66a5e2faf57e..43b6682877d5 100644 --- a/drivers/tty/serial/serial_core.c +++ b/drivers/tty/serial/serial_core.c @@ -3295,8 +3295,10 @@ EXPORT_SYMBOL(uart_remove_one_port); * This function implements the device tree binding described in * Documentation/devicetree/bindings/serial/rs485.txt. */ -void uart_get_rs485_mode(struct device *dev, struct serial_rs485 *rs485conf) +int uart_get_rs485_mode(struct uart_port *port) { + struct serial_rs485 *rs485conf = &port->rs485; + struct device *dev = port->dev; u32 rs485_delay[2]; int ret; @@ -3328,6 +3330,8 @@ void uart_get_rs485_mode(struct device *dev, struct serial_rs485 *rs485conf) rs485conf->flags &= ~SER_RS485_RTS_ON_SEND; rs485conf->flags |= SER_RS485_RTS_AFTER_SEND; } + + return 0; } EXPORT_SYMBOL_GPL(uart_get_rs485_mode); diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c index 5e93e8d40f59..e3db54398159 100644 --- a/drivers/tty/serial/stm32-usart.c +++ b/drivers/tty/serial/stm32-usart.c @@ -158,9 +158,7 @@ static int stm32_init_rs485(struct uart_port *port, if (!pdev->dev.of_node) return -ENODEV; - uart_get_rs485_mode(&pdev->dev, rs485conf); - - return 0; + return uart_get_rs485_mode(port); } static int stm32_pending_rx(struct uart_port *port, u32 *sr, int *last_res, @@ -931,7 +929,9 @@ static int stm32_init_port(struct stm32_port *stm32port, port->rs485_config = stm32_config_rs485; - stm32_init_rs485(port, pdev); + ret = stm32_init_rs485(port, pdev); + if (ret) + return ret; if (stm32port->info->cfg.has_wakeup) { stm32port->wakeirq = platform_get_irq(pdev, 1); diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h index 92f5eba86052..b649a2b894e7 100644 --- a/include/linux/serial_core.h +++ b/include/linux/serial_core.h @@ -472,5 +472,5 @@ extern int uart_handle_break(struct uart_port *port); (cflag) & CRTSCTS || \ !((cflag) & CLOCAL)) -void uart_get_rs485_mode(struct device *dev, struct serial_rs485 *rs485conf); +int uart_get_rs485_mode(struct uart_port *port); #endif /* LINUX_SERIAL_CORE_H */