diff options
| author | Ronald Wahl <ronald.wahl@raritan.com> | 2023-11-01 20:14:31 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-12-13 20:27:05 +0300 |
| commit | 8ffaaf80c64c341cd12c6038be7336fe3e97f263 (patch) | |
| tree | f29c20a8168206efeb8d998c2343092dce8b467d | |
| parent | b74ace5dec53c89bcda010204a5b6ec2589fa673 (diff) | |
| download | linux-8ffaaf80c64c341cd12c6038be7336fe3e97f263.tar.xz | |
serial: 8250: 8250_omap: Do not start RX DMA on THRI interrupt
commit c6bb057418876cdfdd29a6f7b8cef54539ee8811 upstream.
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>
| -rw-r--r-- | drivers/tty/serial/8250/8250_omap.c | 10 |
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 724d82bde877..bd4118f1b694 100644 --- a/drivers/tty/serial/8250/8250_omap.c +++ b/drivers/tty/serial/8250/8250_omap.c @@ -1209,10 +1209,12 @@ 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) { |