X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?p=pandora-kernel.git;a=blobdiff_plain;f=drivers%2Ftty%2Fserial%2Famba-pl011.c;h=3d569cd68f58d5a6550fc37bb87f6d571eeb5de3;hp=6800f5f26241430789a92efea30d58920dca9453;hb=c3d8b76f61586714cdc5f219ba45592a54caaa55;hpb=7256ecc2b7b91b4212ccc5511cb12254bdf806d0

diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index 6800f5f26241..3d569cd68f58 100644
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -51,6 +51,7 @@
 #include <linux/dma-mapping.h>
 #include <linux/scatterlist.h>
 #include <linux/delay.h>
+#include <linux/types.h>
 
 #include <asm/io.h>
 #include <asm/sizes.h>
@@ -271,6 +272,7 @@ static void pl011_dma_probe_initcall(struct uart_amba_port *uap)
 		.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE,
 		.direction = DMA_MEM_TO_DEV,
 		.dst_maxburst = uap->fifosize >> 1,
+		.device_fc = false,
 	};
 	struct dma_chan *chan;
 	dma_cap_mask_t mask;
@@ -304,6 +306,7 @@ static void pl011_dma_probe_initcall(struct uart_amba_port *uap)
 			.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE,
 			.direction = DMA_DEV_TO_MEM,
 			.src_maxburst = uap->fifosize >> 1,
+			.device_fc = false,
 		};
 
 		chan = dma_request_channel(mask, plat->dma_filter, plat->dma_rx_param);
@@ -481,7 +484,7 @@ static int pl011_dma_tx_refill(struct uart_amba_port *uap)
 		return -EBUSY;
 	}
 
-	desc = dma_dev->device_prep_slave_sg(chan, &dmatx->sg, 1, DMA_MEM_TO_DEV,
+	desc = dmaengine_prep_slave_sg(chan, &dmatx->sg, 1, DMA_MEM_TO_DEV,
 					     DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 	if (!desc) {
 		dma_unmap_sg(dma_dev->dev, &dmatx->sg, 1, DMA_TO_DEVICE);
@@ -664,7 +667,6 @@ static void pl011_dma_rx_callback(void *data);
 static int pl011_dma_rx_trigger_dma(struct uart_amba_port *uap)
 {
 	struct dma_chan *rxchan = uap->dmarx.chan;
-	struct dma_device *dma_dev;
 	struct pl011_dmarx_data *dmarx = &uap->dmarx;
 	struct dma_async_tx_descriptor *desc;
 	struct pl011_sgbuf *sgbuf;
@@ -675,8 +677,7 @@ static int pl011_dma_rx_trigger_dma(struct uart_amba_port *uap)
 	/* Start the RX DMA job */
 	sgbuf = uap->dmarx.use_buf_b ?
 		&uap->dmarx.sgbuf_b : &uap->dmarx.sgbuf_a;
-	dma_dev = rxchan->device;
-	desc = rxchan->device->device_prep_slave_sg(rxchan, &sgbuf->sg, 1,
+	desc = dmaengine_prep_slave_sg(rxchan, &sgbuf->sg, 1,
 					DMA_DEV_TO_MEM,
 					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 	/*
@@ -827,7 +828,12 @@ static void pl011_dma_rx_callback(void *data)
 {
 	struct uart_amba_port *uap = data;
 	struct pl011_dmarx_data *dmarx = &uap->dmarx;
+	struct dma_chan *rxchan = dmarx->chan;
 	bool lastbuf = dmarx->use_buf_b;
+	struct pl011_sgbuf *sgbuf = dmarx->use_buf_b ?
+		&dmarx->sgbuf_b : &dmarx->sgbuf_a;
+	size_t pending;
+	struct dma_tx_state state;
 	int ret;
 
 	/*
@@ -838,11 +844,21 @@ static void pl011_dma_rx_callback(void *data)
 	 * we immediately trigger the next DMA job.
 	 */
 	spin_lock_irq(&uap->port.lock);
+	/*
+	 * Rx data can be taken by the UART interrupts during
+	 * the DMA irq handler. So we check the residue here.
+	 */
+	rxchan->device->device_tx_status(rxchan, dmarx->cookie, &state);
+	pending = sgbuf->sg.length - state.residue;
+	BUG_ON(pending > PL011_DMA_BUFFER_SIZE);
+	/* Then we terminate the transfer - we now know our residue */
+	dmaengine_terminate_all(rxchan);
+
 	uap->dmarx.running = false;
 	dmarx->use_buf_b = !lastbuf;
 	ret = pl011_dma_rx_trigger_dma(uap);
 
-	pl011_dma_rx_chars(uap, PL011_DMA_BUFFER_SIZE, lastbuf, false);
+	pl011_dma_rx_chars(uap, pending, lastbuf, false);
 	spin_unlock_irq(&uap->port.lock);
 	/*
 	 * Do this check after we picked the DMA chars so we don't
@@ -1381,6 +1397,10 @@ static int pl011_startup(struct uart_port *port)
 
 	uap->port.uartclk = clk_get_rate(uap->clk);
 
+	/* Clear pending error and receive interrupts */
+	writew(UART011_OEIS | UART011_BEIS | UART011_PEIS | UART011_FEIS |
+	       UART011_RTIS | UART011_RXIS, uap->port.membase + UART011_ICR);
+
 	/*
 	 * Allocate the IRQ
 	 */
@@ -1417,10 +1437,6 @@ static int pl011_startup(struct uart_port *port)
 	cr |= UART01x_CR_UARTEN | UART011_CR_RXE | UART011_CR_TXE;
 	writew(cr, uap->port.membase + UART011_CR);
 
-	/* Clear pending error interrupts */
-	writew(UART011_OEIS | UART011_BEIS | UART011_PEIS | UART011_FEIS,
-	       uap->port.membase + UART011_ICR);
-
 	/*
 	 * initialise the old status of the modem signals
 	 */
@@ -1435,6 +1451,9 @@ static int pl011_startup(struct uart_port *port)
 	 * as well.
 	 */
 	spin_lock_irq(&uap->port.lock);
+	/* Clear out any spuriously appearing RX interrupts */
+	 writew(UART011_RTIS | UART011_RXIS,
+		uap->port.membase + UART011_ICR);
 	uap->im = UART011_RTIM;
 	if (!pl011_dma_rx_running(uap))
 		uap->im |= UART011_RXIM;
@@ -1944,6 +1963,10 @@ static int pl011_probe(struct amba_device *dev, const struct amba_id *id)
 	uap->port.line = i;
 	pl011_dma_probe(uap);
 
+	/* Ensure interrupts from this UART are masked and cleared */
+	writew(0, uap->port.membase + UART011_IMSC);
+	writew(0xffff, uap->port.membase + UART011_ICR);
+
 	snprintf(uap->type, sizeof(uap->type), "PL011 rev%u", amba_rev(dev));
 
 	amba_ports[i] = uap;