From patchwork Fri Aug 15 17:42:35 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sebastian Andrzej Siewior X-Patchwork-Id: 4728761 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 661269F3EE for ; Fri, 15 Aug 2014 17:47:06 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 995A520103 for ; Fri, 15 Aug 2014 17:47:05 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id C83AA2015A for ; Fri, 15 Aug 2014 17:47:04 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1XILY4-0001v5-Uo; Fri, 15 Aug 2014 17:44:20 +0000 Received: from galois.linutronix.de ([2001:470:1f0b:db:abcd:42:0:1]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1XILXY-0001X2-Ej for linux-arm-kernel@lists.infradead.org; Fri, 15 Aug 2014 17:43:48 +0000 Received: from localhost ([127.0.0.1] helo=bazinga.breakpoint.cc) by Galois.linutronix.de with esmtp (Exim 4.80) (envelope-from ) id 1XILWh-0006sE-CR; Fri, 15 Aug 2014 19:42:55 +0200 From: Sebastian Andrzej Siewior To: linux-serial@vger.kernel.org Subject: [PATCH 07/15] tty: serial: 8250_dma: enqueue RX dma again on completion. Date: Fri, 15 Aug 2014 19:42:35 +0200 Message-Id: <1408124563-31541-8-git-send-email-bigeasy@linutronix.de> X-Mailer: git-send-email 2.0.1 In-Reply-To: <1408124563-31541-1-git-send-email-bigeasy@linutronix.de> References: <1408124563-31541-1-git-send-email-bigeasy@linutronix.de> X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1, SHORTCIRCUIT=-0.0001 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20140815_104348_650410_88CA1399 X-CRM114-Status: GOOD ( 10.20 ) X-Spam-Score: -0.7 (/) Cc: tony@atomide.com, Greg Kroah-Hartman , Sebastian Andrzej Siewior , linux-kernel@vger.kernel.org, balbi@ti.com, Vinod Koul , linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-2.6 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_NONE, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The omap needs a DMA request pending right away. If it is enqueued once the bytes are in the FIFO then nothing will happen and the FIFO will be later purged via RX-timeout interrupt. This patch enqueues RX-DMA request on completion but not if it was aborted on error. The first enqueue will happen in the driver in startup. Signed-off-by: Sebastian Andrzej Siewior --- drivers/tty/serial/8250/8250_core.c | 3 +++ drivers/tty/serial/8250/8250_dma.c | 12 +++++++++--- 2 files changed, 12 insertions(+), 3 deletions(-) diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c index 7498ce1..ab2de27 100644 --- a/drivers/tty/serial/8250/8250_core.c +++ b/drivers/tty/serial/8250/8250_core.c @@ -1598,6 +1598,9 @@ int serial8250_handle_irq(struct uart_port *port, unsigned int iir) if (!up->dma || dma_err) status = serial8250_rx_chars(up, status); + + if (dma_err && port->type == PORT_OMAP_16750) + serial8250_rx_dma(up, 0); } serial8250_modem_status(up); if ((!up->dma || up->dma_tx_err) && (status & UART_LSR_THRE)) diff --git a/drivers/tty/serial/8250/8250_dma.c b/drivers/tty/serial/8250/8250_dma.c index 5c59b15..7417ed5 100644 --- a/drivers/tty/serial/8250/8250_dma.c +++ b/drivers/tty/serial/8250/8250_dma.c @@ -50,9 +50,8 @@ static void __dma_tx_complete(void *param) spin_unlock_irqrestore(&p->port.lock, flags); } -static void __dma_rx_complete(void *param) +static void __dma_rx_do_complete(struct uart_8250_port *p, bool error) { - struct uart_8250_port *p = param; struct uart_8250_dma *dma = p->dma; struct tty_port *tty_port = &p->port.state->port; struct dma_tx_state state; @@ -68,10 +67,17 @@ static void __dma_rx_complete(void *param) tty_insert_flip_string(tty_port, dma->rx_buf, count); p->port.icount.rx += count; + if (!error && p->port.type == PORT_OMAP_16750) + serial8250_rx_dma(p, 0); tty_flip_buffer_push(tty_port); } +static void __dma_rx_complete(void *param) +{ + __dma_rx_do_complete(param, false); +} + int serial8250_tx_dma(struct uart_8250_port *p) { struct uart_8250_dma *dma = p->dma; @@ -139,7 +145,7 @@ int serial8250_rx_dma(struct uart_8250_port *p, unsigned int iir) */ if (dma_status == DMA_IN_PROGRESS) { dmaengine_pause(dma->rxchan); - __dma_rx_complete(p); + __dma_rx_do_complete(p, true); } return -ETIMEDOUT; default: