From a700f2d8e79ff80041078f160fe1edccf89b0c66 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Wed, 23 Sep 2015 12:33:14 -0300 Subject: Linux-libre 4.2.1-gnu --- drivers/tty/serial/8250/8250_omap.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) (limited to 'drivers/tty/serial/8250/8250_omap.c') diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c index d75a66c72..b470df122 100644 --- a/drivers/tty/serial/8250/8250_omap.c +++ b/drivers/tty/serial/8250/8250_omap.c @@ -100,6 +100,7 @@ struct omap8250_priv { struct work_struct qos_work; struct uart_8250_dma omap8250_dma; spinlock_t rx_dma_lock; + bool rx_dma_broken; }; static u32 uart_read(struct uart_8250_port *up, u32 reg) @@ -754,6 +755,7 @@ static void omap_8250_rx_dma_flush(struct uart_8250_port *p) struct omap8250_priv *priv = p->port.private_data; struct uart_8250_dma *dma = p->dma; unsigned long flags; + int ret; spin_lock_irqsave(&priv->rx_dma_lock, flags); @@ -762,7 +764,9 @@ static void omap_8250_rx_dma_flush(struct uart_8250_port *p) return; } - dmaengine_pause(dma->rxchan); + ret = dmaengine_pause(dma->rxchan); + if (WARN_ON_ONCE(ret)) + priv->rx_dma_broken = true; spin_unlock_irqrestore(&priv->rx_dma_lock, flags); @@ -806,6 +810,9 @@ static int omap_8250_rx_dma(struct uart_8250_port *p, unsigned int iir) break; } + if (priv->rx_dma_broken) + return -EINVAL; + spin_lock_irqsave(&priv->rx_dma_lock, flags); if (dma->rx_running) @@ -1180,6 +1187,11 @@ static int omap8250_probe(struct platform_device *pdev) if (of_machine_is_compatible("ti,am33xx")) priv->habit |= OMAP_DMA_TX_KICK; + /* + * pause is currently not supported atleast on omap-sdma + * and edma on most earlier kernels. + */ + priv->rx_dma_broken = true; } } #endif -- cgit v1.2.3-54-g00ecf