[PATCH v1 1/1] serial: 8250_dw: Allow hardware flow control to be used
From: Jason Uy <hidden>
Date: 2016-12-06 22:34:53
Also in:
lkml
Subsystem:
8250/16?50 (and clone uarts) serial driver, synopsys designware 8250 uart driver, the rest, tty layer and serial drivers · Maintainers:
Greg Kroah-Hartman, Ilpo Järvinen, Linus Torvalds, Jiri Slaby
In the most common use case, the Synopsys DW UART driver does not set the set_termios callback function. This prevents UPSTAT_AUTOCTS from being set when the UART flag CRTSCTS is set. As a result, the driver will use software flow control as opposed to hardware flow control. To fix the problem, the set_termios callback function is set to the DW specific function. The logic to set UPSTAT_AUTOCTS is moved so that any clock error will not affect setting the hardware flow control. Reviewed-by: Scott Branden <scott.branden@broadcom.com> Reviewed-by: Ray Jui <redacted> Signed-off-by: Jason Uy <redacted> --- drivers/tty/serial/8250/8250_dw.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c
index 459d726..18f1f8b 100644
--- a/drivers/tty/serial/8250/8250_dw.c
+++ b/drivers/tty/serial/8250/8250_dw.c@@ -246,11 +246,11 @@ static void dw8250_set_termios(struct uart_port *p, struct ktermios *termios, if (!ret) p->uartclk = rate; +out: p->status &= ~UPSTAT_AUTOCTS; if (termios->c_cflag & CRTSCTS) p->status |= UPSTAT_AUTOCTS; -out: serial8250_do_set_termios(p, termios, old); }
@@ -308,13 +308,11 @@ static void dw8250_quirks(struct uart_port *p, struct dw8250_data *data) p->serial_in = dw8250_serial_in32; data->uart_16550_compatible = true; } - p->set_termios = dw8250_set_termios; } /* Platforms with iDMA */ if (platform_get_resource_byname(to_platform_device(p->dev), IORESOURCE_MEM, "lpss_priv")) { - p->set_termios = dw8250_set_termios; data->dma.rx_param = p->dev->parent; data->dma.tx_param = p->dev->parent; data->dma.fn = dw8250_idma_filter;
@@ -392,6 +390,7 @@ static int dw8250_probe(struct platform_device *pdev) p->iotype = UPIO_MEM; p->serial_in = dw8250_serial_in; p->serial_out = dw8250_serial_out; + p->set_termios = dw8250_set_termios; p->membase = devm_ioremap(dev, regs->start, resource_size(regs)); if (!p->membase)
--
1.9.1