Merge tag 'iwlwifi-for-kalle-2015-01-15' of https://git.kernel.org/pub/scm/linux...

[firefly-linux-kernel-4.4.55.git] / drivers / tty / serial / amba-pl011.c

diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index 02016fcd91b850424c7534ce5a5ddc0ab7e6ecd1..8d94c194f090b8ed16ae1e9a418502f224041e36 100644 (file)
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -246,6 +246,7 @@ static int pl011_sgbuf_init(struct dma_chan *chan, struct pl011_sgbuf *sg,
        sg_set_page(&sg->sg, phys_to_page(dma_addr),
                PL011_DMA_BUFFER_SIZE, offset_in_page(dma_addr));
        sg_dma_address(&sg->sg) = dma_addr;
+       sg_dma_len(&sg->sg) = PL011_DMA_BUFFER_SIZE;
 
        return 0;
 }
@@ -321,10 +322,26 @@ static void pl011_dma_probe_initcall(struct device *dev, struct uart_amba_port *
                        .src_maxburst = uap->fifosize >> 2,
                        .device_fc = false,
                };
+               struct dma_slave_caps caps;
 
+               /*
+                * Some DMA controllers provide information on their capabilities.
+                * If the controller does, check for suitable residue processing
+                * otherwise assime all is well.
+                */
+               if (0 == dma_get_slave_caps(chan, &caps)) {
+                       if (caps.residue_granularity ==
+                                       DMA_RESIDUE_GRANULARITY_DESCRIPTOR) {
+                               dma_release_channel(chan);
+                               dev_info(uap->port.dev,
+                                       "RX DMA disabled - no residue processing\n");
+                               return;
+                       }
+               }
                dmaengine_slave_config(chan, &rx_conf);
                uap->dmarx.chan = chan;
 
+               uap->dmarx.auto_poll_rate = false;
                if (plat && plat->dma_rx_poll_enable) {
                        /* Set poll rate if specified. */
                        if (plat->dma_rx_poll_rate) {
@@ -345,9 +362,24 @@ static void pl011_dma_probe_initcall(struct device *dev, struct uart_amba_port *
                                        plat->dma_rx_poll_timeout;
                        else
                                uap->dmarx.poll_timeout = 3000;
-               } else
-                       uap->dmarx.auto_poll_rate = false;
-
+               } else if (!plat && dev->of_node) {
+                       uap->dmarx.auto_poll_rate = of_property_read_bool(
+                                               dev->of_node, "auto-poll");
+                       if (uap->dmarx.auto_poll_rate) {
+                               u32 x;
+
+                               if (0 == of_property_read_u32(dev->of_node,
+                                               "poll-rate-ms", &x))
+                                       uap->dmarx.poll_rate = x;
+                               else
+                                       uap->dmarx.poll_rate = 100;
+                               if (0 == of_property_read_u32(dev->of_node,
+                                               "poll-timeout-ms", &x))
+                                       uap->dmarx.poll_timeout = x;
+                               else
+                                       uap->dmarx.poll_timeout = 3000;
+                       }
+               }
                dev_info(uap->port.dev, "DMA channel RX %s\n",
                         dma_chan_name(uap->dmarx.chan));
        }
@@ -501,7 +533,11 @@ static int pl011_dma_tx_refill(struct uart_amba_port *uap)
                memcpy(&dmatx->buf[0], &xmit->buf[xmit->tail], count);
        else {
                size_t first = UART_XMIT_SIZE - xmit->tail;
-               size_t second = xmit->head;
+               size_t second;
+
+               if (first > count)
+                       first = count;
+               second = count - first;
 
                memcpy(&dmatx->buf[0], &xmit->buf[xmit->tail], first);
                if (second)
@@ -988,7 +1024,7 @@ static void pl011_dma_startup(struct uart_amba_port *uap)
        if (!uap->dmatx.chan)
                return;
 
-       uap->dmatx.buf = kmalloc(PL011_DMA_BUFFER_SIZE, GFP_KERNEL);
+       uap->dmatx.buf = kmalloc(PL011_DMA_BUFFER_SIZE, GFP_KERNEL | __GFP_DMA);
        if (!uap->dmatx.buf) {
                dev_err(uap->port.dev, "no memory for DMA TX buffer\n");
                uap->port.fifosize = uap->fifosize;
@@ -1689,6 +1725,8 @@ static void pl011_shutdown(struct uart_port *port)
                        plat->exit();
        }
 
+       if (uap->port.ops->flush_buffer)
+               uap->port.ops->flush_buffer(port);
 }
 
 static void