From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754140AbaG2TBb (ORCPT ); Tue, 29 Jul 2014 15:01:31 -0400 Received: from www.linutronix.de ([62.245.132.108]:50355 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751397AbaG2TAS (ORCPT ); Tue, 29 Jul 2014 15:00:18 -0400 From: Sebastian Andrzej Siewior To: linux-serial@vger.kernel.org Cc: linux-kernel@vger.kernel.org, linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org, tony@atomide.com, balbi@ti.com, Sebastian Andrzej Siewior , Heikki Krogerus , Greg Kroah-Hartman Subject: [PATCH 3/7] serial: 8250_dma: continue TX dma on dma error Date: Tue, 29 Jul 2014 20:59:00 +0200 Message-Id: <1406660344-25307-4-git-send-email-bigeasy@linutronix.de> X-Mailer: git-send-email 2.0.1 In-Reply-To: <1406660344-25307-1-git-send-email-bigeasy@linutronix.de> References: <1406660344-25307-1-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 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org After TX dma completes the code will queue another DMA transfer. If serial8250_tx_dma() fails then there is no plan B to continue the transfer manually. This patch enables the TX-fifo empty event so it can be tried again via DMA or use the manual fallback in case it fails. Cc: Heikki Krogerus Cc: Greg Kroah-Hartman Signed-off-by: Sebastian Andrzej Siewior --- drivers/tty/serial/8250/8250_dma.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/drivers/tty/serial/8250/8250_dma.c b/drivers/tty/serial/8250/8250_dma.c index 148ffe4..f9ef69f 100644 --- a/drivers/tty/serial/8250/8250_dma.c +++ b/drivers/tty/serial/8250/8250_dma.c @@ -36,8 +36,15 @@ static void __dma_tx_complete(void *param) if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) uart_write_wakeup(&p->port); - if (!uart_circ_empty(xmit) && !uart_tx_stopped(&p->port)) - serial8250_tx_dma(p); + if (!uart_circ_empty(xmit) && !uart_tx_stopped(&p->port)) { + int ret; + + ret = serial8250_tx_dma(p); + if (ret && !(p->ier & UART_IER_THRI)) { + p->ier |= UART_IER_THRI; + serial_port_out(&p->port, UART_IER, p->ier); + } + } spin_unlock_irqrestore(&p->port.lock, flags); } -- 2.0.1