The loopback test mode is not implemented in all NS16550 compatible UARTs. The 8250 driver uses the UPF_SKIP_TEST flag to indicate this, however it is not possible to set this flag via device-tree. Add a new 'no-loopback-test' property, and modify the of_serial driver to set the UPF_SKIP_TEST flag if the property is present. Signed-off-by: Gabor Juhos <juhosg@xxxxxxxxxxx> --- .../devicetree/bindings/tty/serial/of-serial.txt | 2 ++ drivers/tty/serial/of_serial.c | 4 ++++ 2 files changed, 6 insertions(+), 0 deletions(-) diff --git a/Documentation/devicetree/bindings/tty/serial/of-serial.txt b/Documentation/devicetree/bindings/tty/serial/of-serial.txt index b8b27b0..0e83e45 100644 --- a/Documentation/devicetree/bindings/tty/serial/of-serial.txt +++ b/Documentation/devicetree/bindings/tty/serial/of-serial.txt @@ -24,6 +24,8 @@ Optional properties: accesses to the UART (e.g. TI davinci). - used-by-rtas : set to indicate that the port is in use by the OpenFirmware RTAS and should not be registered. +- no-loopback-test: set to indicate that the port does not implements loopback + test mode Example: diff --git a/drivers/tty/serial/of_serial.c b/drivers/tty/serial/of_serial.c index 5410c06..301e5e3 100644 --- a/drivers/tty/serial/of_serial.c +++ b/drivers/tty/serial/of_serial.c @@ -105,6 +105,10 @@ static int __devinit of_platform_serial_setup(struct platform_device *ofdev, port->uartclk = clk; port->flags = UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF | UPF_IOREMAP | UPF_FIXED_PORT | UPF_FIXED_TYPE; + + if (of_find_property(np, "no-loopback-test", NULL)) + port->flags |= UPF_SKIP_TEST; + port->dev = &ofdev->dev; if (type == PORT_TEGRA) -- 1.7.2.1 -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
