4.19-stable review patch. If anyone has any objections, please let me know.
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From: Loys Ollivier lollivier@baylibre.com
[ Upstream commit a26988e8fef4b258d1b771e0f4b2e3b67cb2e044 ]
At probe, the uart driver tries to get an id from a device tree alias. When no alias was specified, the driver would return an error and probing would fail.
Providing an alias for registering a serial device should not be mandatory. If the device tree does not specify an alias, provide an id from a reserved range so that the probing can continue.
Suggested-by: Rob Herring robh@kernel.org Signed-off-by: Loys Ollivier lollivier@baylibre.com Reviewed-by: Neil Armstrong narmstrong@baylibre.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Stable-dep-of: 2a1d728f20ed ("tty: serial: meson: fix hard LOCKUP on crtscts mode") Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/tty/serial/meson_uart.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-)
diff --git a/drivers/tty/serial/meson_uart.c b/drivers/tty/serial/meson_uart.c index 1838d0be37044..849ce8c1ef392 100644 --- a/drivers/tty/serial/meson_uart.c +++ b/drivers/tty/serial/meson_uart.c @@ -72,7 +72,8 @@ #define AML_UART_BAUD_USE BIT(23) #define AML_UART_BAUD_XTAL BIT(24)
-#define AML_UART_PORT_NUM 6 +#define AML_UART_PORT_NUM 12 +#define AML_UART_PORT_OFFSET 6 #define AML_UART_DEV_NAME "ttyAML"
@@ -667,10 +668,20 @@ static int meson_uart_probe(struct platform_device *pdev) struct resource *res_mem, *res_irq; struct uart_port *port; int ret = 0; + int id = -1;
if (pdev->dev.of_node) pdev->id = of_alias_get_id(pdev->dev.of_node, "serial");
+ if (pdev->id < 0) { + for (id = AML_UART_PORT_OFFSET; id < AML_UART_PORT_NUM; id++) { + if (!meson_ports[id]) { + pdev->id = id; + break; + } + } + } + if (pdev->id < 0 || pdev->id >= AML_UART_PORT_NUM) return -EINVAL;