Merge tag 'sound-4.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai...

[karo-tx-linux.git] / drivers / tty / serial / fsl_lpuart.c

diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c
index a1c6519837a40d4e562e9bea834728e48511b733..f02934ffb3293de45601f434be9dd7786cafdfe4 100644 (file)
--- a/drivers/tty/serial/fsl_lpuart.c
+++ b/drivers/tty/serial/fsl_lpuart.c
@@ -1407,6 +1407,18 @@ lpuart_set_termios(struct uart_port *port, struct ktermios *termios,
        /* ask the core to calculate the divisor */
        baud = uart_get_baud_rate(port, termios, old, 50, port->uartclk / 16);
 
+       /*
+        * Need to update the Ring buffer length according to the selected
+        * baud rate and restart Rx DMA path.
+        *
+        * Since timer function acqures sport->port.lock, need to stop before
+        * acquring same lock because otherwise del_timer_sync() can deadlock.
+        */
+       if (old && sport->lpuart_dma_rx_use) {
+               del_timer_sync(&sport->lpuart_timer);
+               lpuart_dma_rx_free(&sport->port);
+       }
+
        spin_lock_irqsave(&sport->port.lock, flags);
 
        sport->port.read_status_mask = 0;
@@ -1456,22 +1468,11 @@ lpuart_set_termios(struct uart_port *port, struct ktermios *termios,
        /* restore control register */
        writeb(old_cr2, sport->port.membase + UARTCR2);
 
-       /*
-        * If new baud rate is set, we will also need to update the Ring buffer
-        * length according to the selected baud rate and restart Rx DMA path.
-        */
-       if (old) {
-               if (sport->lpuart_dma_rx_use) {
-                       del_timer_sync(&sport->lpuart_timer);
-                       lpuart_dma_rx_free(&sport->port);
-               }
-
-               if (sport->dma_rx_chan && !lpuart_start_rx_dma(sport)) {
-                       sport->lpuart_dma_rx_use = true;
+       if (old && sport->lpuart_dma_rx_use) {
+               if (!lpuart_start_rx_dma(sport))
                        rx_dma_timer_init(sport);
-               } else {
+               else
                        sport->lpuart_dma_rx_use = false;
-               }
        }
 
        spin_unlock_irqrestore(&sport->port.lock, flags);
@@ -2131,12 +2132,10 @@ static int lpuart_resume(struct device *dev)
 
        if (sport->lpuart_dma_rx_use) {
                if (sport->port.irq_wake) {
-                       if (!lpuart_start_rx_dma(sport)) {
-                               sport->lpuart_dma_rx_use = true;
+                       if (!lpuart_start_rx_dma(sport))
                                rx_dma_timer_init(sport);
-                       } else {
+                       else
                                sport->lpuart_dma_rx_use = false;
-                       }
                }
        }