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path: root/drivers/tty/serial/fsl_lpuart.c
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Diffstat (limited to 'drivers/tty/serial/fsl_lpuart.c')
-rw-r--r--drivers/tty/serial/fsl_lpuart.c44
1 files changed, 42 insertions, 2 deletions
diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c
index 159a2de509f3..5c889c65d8ea 100644
--- a/drivers/tty/serial/fsl_lpuart.c
+++ b/drivers/tty/serial/fsl_lpuart.c
@@ -288,6 +288,7 @@ struct lpuart_port {
wait_queue_head_t dma_wait;
bool is_cs7; /* Set to true when character size is 7 */
/* and the parity is enabled */
+ bool dma_idle_int;
};
struct lpuart_soc_data {
@@ -1246,7 +1247,8 @@ exit:
spin_unlock_irqrestore(&sport->port.lock, flags);
tty_flip_buffer_push(port);
- mod_timer(&sport->lpuart_timer, jiffies + sport->dma_rx_timeout);
+ if (!sport->dma_idle_int)
+ mod_timer(&sport->lpuart_timer, jiffies + sport->dma_rx_timeout);
}
static void lpuart_dma_rx_complete(void *arg)
@@ -1256,6 +1258,28 @@ static void lpuart_dma_rx_complete(void *arg)
lpuart_copy_rx_to_tty(sport);
}
+static void lpuart32_dma_idleint(struct lpuart_port *sport)
+{
+ enum dma_status dmastat;
+ struct dma_chan *chan = sport->dma_rx_chan;
+ struct circ_buf *ring = &sport->rx_ring;
+ struct dma_tx_state state;
+ int count = 0;
+
+ dmastat = dmaengine_tx_status(chan, sport->dma_rx_cookie, &state);
+ if (dmastat == DMA_ERROR) {
+ dev_err(sport->port.dev, "Rx DMA transfer failed!\n");
+ return;
+ }
+
+ ring->head = sport->rx_sgl.length - state.residue;
+ count = CIRC_CNT(ring->head, ring->tail, sport->rx_sgl.length);
+
+ /* Check if new data received before copying */
+ if (count)
+ lpuart_copy_rx_to_tty(sport);
+}
+
static irqreturn_t lpuart32_int(int irq, void *dev_id)
{
struct lpuart_port *sport = dev_id;
@@ -1271,6 +1295,9 @@ static irqreturn_t lpuart32_int(int irq, void *dev_id)
if ((sts & UARTSTAT_TDRE) && !sport->lpuart_dma_tx_use)
lpuart32_txint(sport);
+ if ((sts & UARTSTAT_IDLE) && sport->lpuart_dma_rx_use && sport->dma_idle_int)
+ lpuart32_dma_idleint(sport);
+
lpuart32_write(&sport->port, sts, UARTSTAT);
return IRQ_HANDLED;
}
@@ -1391,6 +1418,12 @@ static inline int lpuart_start_rx_dma(struct lpuart_port *sport)
unsigned long temp = lpuart32_read(&sport->port, UARTBAUD);
lpuart32_write(&sport->port, temp | UARTBAUD_RDMAE, UARTBAUD);
+
+ if (sport->dma_idle_int) {
+ unsigned long ctrl = lpuart32_read(&sport->port, UARTCTRL);
+
+ lpuart32_write(&sport->port, ctrl | UARTCTRL_ILIE, UARTCTRL);
+ }
} else {
writeb(readb(sport->port.membase + UARTCR5) | UARTCR5_RDMAS,
sport->port.membase + UARTCR5);
@@ -1406,7 +1439,9 @@ static void lpuart_dma_rx_free(struct uart_port *port)
struct dma_chan *chan = sport->dma_rx_chan;
dmaengine_terminate_sync(chan);
- del_timer_sync(&sport->lpuart_timer);
+ if (!sport->dma_idle_int)
+ del_timer_sync(&sport->lpuart_timer);
+
dma_unmap_sg(chan->device->dev, &sport->rx_sgl, 1, DMA_FROM_DEVICE);
kfree(sport->rx_ring.buf);
sport->rx_ring.tail = 0;
@@ -1668,6 +1703,9 @@ static void lpuart32_setup_watermark_enable(struct lpuart_port *sport)
static void rx_dma_timer_init(struct lpuart_port *sport)
{
+ if (sport->dma_idle_int)
+ return;
+
timer_setup(&sport->lpuart_timer, lpuart_timer_func, 0);
sport->lpuart_timer.expires = jiffies + sport->dma_rx_timeout;
add_timer(&sport->lpuart_timer);
@@ -2821,6 +2859,8 @@ static int lpuart_probe(struct platform_device *pdev)
sport->port.type = PORT_LPUART;
sport->devtype = sdata->devtype;
sport->rx_watermark = sdata->rx_watermark;
+ sport->dma_idle_int = is_imx7ulp_lpuart(sport) || is_imx8ulp_lpuart(sport) ||
+ is_imx8qxp_lpuart(sport);
ret = platform_get_irq(pdev, 0);
if (ret < 0)
return ret;