4.19-stable review patch. If anyone has any objections, please let me know.
------------------
From: Loys Ollivier <lollivier@xxxxxxxxxxxx>
[ 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@xxxxxxxxxx>
Signed-off-by: Loys Ollivier <lollivier@xxxxxxxxxxxx>
Reviewed-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Stable-dep-of: 2a1d728f20ed ("tty: serial: meson: fix hard LOCKUP on crtscts mode")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
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;
--
2.42.0
