summaryrefslogtreecommitdiff
path: root/drivers/tty/serial/8250
diff options
context:
space:
mode:
authorRonald Wahl <ronald.wahl@raritan.com>2023-11-01 20:14:31 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2023-11-23 23:20:16 +0300
commitc6bb057418876cdfdd29a6f7b8cef54539ee8811 (patch)
tree4c312ad321d92dea5753536f96ac5f21a9de3f39 /drivers/tty/serial/8250
parent98b1cc82c4affc16f5598d4fa14b1858671b2263 (diff)
downloadlinux-c6bb057418876cdfdd29a6f7b8cef54539ee8811.tar.xz
serial: 8250: 8250_omap: Do not start RX DMA on THRI interrupt
Starting RX DMA on THRI interrupt is too early because TX may not have finished yet. This change is inspired by commit 90b8596ac460 ("serial: 8250: Prevent starting up DMA Rx on THRI interrupt") and fixes DMA issues I had with an AM62 SoC that is using the 8250 OMAP variant. Cc: stable@vger.kernel.org Fixes: c26389f998a8 ("serial: 8250: 8250_omap: Add DMA support for UARTs on K3 SoCs") Signed-off-by: Ronald Wahl <ronald.wahl@raritan.com> Reviewed-by: Vignesh Raghavendra <vigneshr@ti.com> Link: https://lore.kernel.org/r/20231101171431.16495-1-rwahl@gmx.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/serial/8250')
-rw-r--r--drivers/tty/serial/8250/8250_omap.c10
1 files changed, 6 insertions, 4 deletions
diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c
index 2d42f485c987..7d99bc3be0b8 100644
--- a/drivers/tty/serial/8250/8250_omap.c
+++ b/drivers/tty/serial/8250/8250_omap.c
@@ -1298,10 +1298,12 @@ static int omap_8250_dma_handle_irq(struct uart_port *port)
status = serial_port_in(port, UART_LSR);
- if (priv->habit & UART_HAS_EFR2)
- am654_8250_handle_rx_dma(up, iir, status);
- else
- status = omap_8250_handle_rx_dma(up, iir, status);
+ if ((iir & 0x3f) != UART_IIR_THRI) {
+ if (priv->habit & UART_HAS_EFR2)
+ am654_8250_handle_rx_dma(up, iir, status);
+ else
+ status = omap_8250_handle_rx_dma(up, iir, status);
+ }
serial8250_modem_status(up);
if (status & UART_LSR_THRE && up->dma->tx_err) {