From ffea043965e4634617485b4d313d6c0099d817f0 Mon Sep 17 00:00:00 2001 From: Thor Thayer Date: Thu, 22 Sep 2016 14:56:15 -0500 Subject: [PATCH] serial: 8250: of: Load TX FIFO Threshold from DT Initialize the tx_loadsz parameter from passed in devicetree tx-threshold parameter. The tx_loadsz is calculated as the number of bytes to fill FIFO when tx-threshold is triggered. Signed-off-by: Thor Thayer Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/8250/8250_of.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/tty/serial/8250/8250_of.c b/drivers/tty/serial/8250/8250_of.c index 38963d7bcf84..7a8b5fc81a19 100644 --- a/drivers/tty/serial/8250/8250_of.c +++ b/drivers/tty/serial/8250/8250_of.c @@ -195,6 +195,7 @@ static int of_platform_serial_probe(struct platform_device *ofdev) switch (port_type) { case PORT_8250 ... PORT_MAX_8250: { + u32 tx_threshold; struct uart_8250_port port8250; memset(&port8250, 0, sizeof(port8250)); port8250.port = port; @@ -202,6 +203,12 @@ static int of_platform_serial_probe(struct platform_device *ofdev) if (port.fifosize) port8250.capabilities = UART_CAP_FIFO; + /* Check for TX FIFO threshold & set tx_loadsz */ + if ((of_property_read_u32(ofdev->dev.of_node, "tx-threshold", + &tx_threshold) == 0) && + (tx_threshold < port.fifosize)) + port8250.tx_loadsz = port.fifosize - tx_threshold; + if (of_property_read_bool(ofdev->dev.of_node, "auto-flow-control")) port8250.capabilities |= UART_CAP_AFE; -- 2.39.5