From patchwork Thu Mar 4 21:38:56 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hector Martin X-Patchwork-Id: 12116915 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,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 D79B0C433E0 for ; Thu, 4 Mar 2021 21:47:59 +0000 (UTC) Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id F068164FF1 for ; Thu, 4 Mar 2021 21:47:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F068164FF1 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=marcan.st Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=desiato.20200630; h=Sender:Content-Transfer-Encoding :Content-Type:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To:Message-Id:Date: Subject:Cc:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=eReqC7NRW+IqEVpYznm/lvD2Pj/8Sg06pzf+ZhnDb8A=; b=cRw8dtf+qN64Sdnz06diwD2El ew4hSy/AyOFj53b9XeUWxe1tRJw1nsjfOi3nXbN30nxRJ5rliq+alQoLRU5iYdswo0F4GbqJpqhmN HPd2h/bXLVZ/p99kX753mHP/gXkbxKBRh7LHe7FUP7tBFhZzXoal4f8YgpauueB4wfGG4JuWWw8L4 SIG4Ap/jaKMIwPvJbecFQBjOmPgM4t9d5v49PjBxMiz/9lIPmx7FiQ66movQhQWimiRHnTNqZVouk l6iAAF2k0qVPn+RGeeCoF4f9e6YB7DGmR/VapLEL+oSbVSB0b0oJVpAnwE2fG0EpQhizgHTo61N1S HOKC5XsVg==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lHvnM-00AGmj-Cl; Thu, 04 Mar 2021 21:46:09 +0000 Received: from marcansoft.com ([212.63.210.85] helo=mail.marcansoft.com) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lHvjM-00AEPN-GJ for linux-arm-kernel@lists.infradead.org; Thu, 04 Mar 2021 21:42:02 +0000 Received: from [127.0.0.1] (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: hector@marcansoft.com) by mail.marcansoft.com (Postfix) with ESMTPSA id 0C02E426FC; Thu, 4 Mar 2021 21:41:49 +0000 (UTC) From: Hector Martin To: linux-arm-kernel@lists.infradead.org Cc: Hector Martin , Marc Zyngier , Rob Herring , Arnd Bergmann , Olof Johansson , Krzysztof Kozlowski , Mark Kettenis , Tony Lindgren , Mohamed Mediouni , Stan Skowronek , Alexander Graf , Will Deacon , Linus Walleij , Mark Rutland , Andy Shevchenko , Greg Kroah-Hartman , Jonathan Corbet , Catalin Marinas , Christoph Hellwig , "David S. Miller" , devicetree@vger.kernel.org, linux-serial@vger.kernel.org, linux-doc@vger.kernel.org, linux-samsung-soc@vger.kernel.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [RFT PATCH v3 21/27] tty: serial: samsung_tty: IRQ rework Date: Fri, 5 Mar 2021 06:38:56 +0900 Message-Id: <20210304213902.83903-22-marcan@marcan.st> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20210304213902.83903-1-marcan@marcan.st> References: <20210304213902.83903-1-marcan@marcan.st> MIME-Version: 1.0 X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org * Split out s3c24xx_serial_tx_chars from s3c24xx_serial_tx_irq, where only the latter acquires the port lock. This will be necessary on platforms which have edge-triggered IRQs, as we need to call s3c24xx_serial_tx_chars to kick off transmission from outside IRQ context, with the port lock held. * Rename s3c24xx_serial_rx_chars to s3c24xx_serial_rx_irq for consistency with the above. All it does now is call two other functions anyway. Signed-off-by: Hector Martin Reviewed-by: Krzysztof Kozlowski Tested-by: Krzysztof Kozlowski --- drivers/tty/serial/samsung_tty.c | 34 +++++++++++++++++++------------- 1 file changed, 20 insertions(+), 14 deletions(-) diff --git a/drivers/tty/serial/samsung_tty.c b/drivers/tty/serial/samsung_tty.c index 39b2eb165bdc..7106eb238d8c 100644 --- a/drivers/tty/serial/samsung_tty.c +++ b/drivers/tty/serial/samsung_tty.c @@ -827,7 +827,7 @@ static irqreturn_t s3c24xx_serial_rx_chars_pio(void *dev_id) return IRQ_HANDLED; } -static irqreturn_t s3c24xx_serial_rx_chars(int irq, void *dev_id) +static irqreturn_t s3c24xx_serial_rx_irq(int irq, void *dev_id) { struct s3c24xx_uart_port *ourport = dev_id; @@ -836,16 +836,12 @@ static irqreturn_t s3c24xx_serial_rx_chars(int irq, void *dev_id) return s3c24xx_serial_rx_chars_pio(dev_id); } -static irqreturn_t s3c24xx_serial_tx_chars(int irq, void *id) +static void s3c24xx_serial_tx_chars(struct s3c24xx_uart_port *ourport) { - struct s3c24xx_uart_port *ourport = id; struct uart_port *port = &ourport->port; struct circ_buf *xmit = &port->state->xmit; - unsigned long flags; int count, dma_count = 0; - spin_lock_irqsave(&port->lock, flags); - count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE); if (ourport->dma && ourport->dma->tx_chan && @@ -862,7 +858,7 @@ static irqreturn_t s3c24xx_serial_tx_chars(int irq, void *id) wr_reg(port, S3C2410_UTXH, port->x_char); port->icount.tx++; port->x_char = 0; - goto out; + return; } /* if there isn't anything more to transmit, or the uart is now @@ -871,7 +867,7 @@ static irqreturn_t s3c24xx_serial_tx_chars(int irq, void *id) if (uart_circ_empty(xmit) || uart_tx_stopped(port)) { s3c24xx_serial_stop_tx(port); - goto out; + return; } /* try and drain the buffer... */ @@ -893,7 +889,7 @@ static irqreturn_t s3c24xx_serial_tx_chars(int irq, void *id) if (!count && dma_count) { s3c24xx_serial_start_tx_dma(ourport, dma_count); - goto out; + return; } if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) { @@ -904,8 +900,18 @@ static irqreturn_t s3c24xx_serial_tx_chars(int irq, void *id) if (uart_circ_empty(xmit)) s3c24xx_serial_stop_tx(port); +} + +static irqreturn_t s3c24xx_serial_tx_irq(int irq, void *id) +{ + struct s3c24xx_uart_port *ourport = id; + struct uart_port *port = &ourport->port; + unsigned long flags; + + spin_lock_irqsave(&port->lock, flags); + + s3c24xx_serial_tx_chars(ourport); -out: spin_unlock_irqrestore(&port->lock, flags); return IRQ_HANDLED; } @@ -919,11 +925,11 @@ static irqreturn_t s3c64xx_serial_handle_irq(int irq, void *id) irqreturn_t ret = IRQ_HANDLED; if (pend & S3C64XX_UINTM_RXD_MSK) { - ret = s3c24xx_serial_rx_chars(irq, id); + ret = s3c24xx_serial_rx_irq(irq, id); wr_regl(port, S3C64XX_UINTP, S3C64XX_UINTM_RXD_MSK); } if (pend & S3C64XX_UINTM_TXD_MSK) { - ret = s3c24xx_serial_tx_chars(irq, id); + ret = s3c24xx_serial_tx_irq(irq, id); wr_regl(port, S3C64XX_UINTP, S3C64XX_UINTM_TXD_MSK); } return ret; @@ -1155,7 +1161,7 @@ static int s3c24xx_serial_startup(struct uart_port *port) ourport->rx_enabled = 1; - ret = request_irq(ourport->rx_irq, s3c24xx_serial_rx_chars, 0, + ret = request_irq(ourport->rx_irq, s3c24xx_serial_rx_irq, 0, s3c24xx_serial_portname(port), ourport); if (ret != 0) { @@ -1169,7 +1175,7 @@ static int s3c24xx_serial_startup(struct uart_port *port) ourport->tx_enabled = 1; - ret = request_irq(ourport->tx_irq, s3c24xx_serial_tx_chars, 0, + ret = request_irq(ourport->tx_irq, s3c24xx_serial_tx_irq, 0, s3c24xx_serial_portname(port), ourport); if (ret) {