[PATCH v2 2/2] serial: stm32: support probing with missing clock provider

[Ahmad Fatoum <a.fatoum@pengutronix.de>]

The STM32MP135F-DK support in barebox has bitrotted, because of changes
to the upstream device tree: The root of the clock tree is now provided
by OP-TEE over SCMI for which no support exists in barebox, so drivers
requesting clocks will defer indefinitely, including the console device.

A series adding OP-TEE SCMI support will follow, but for now, let's
ensure that console registration isn't deferred in such a case.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
---
v1 -> v2:
  - no change
---
 drivers/serial/serial_stm32.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/serial/serial_stm32.c b/drivers/serial/serial_stm32.c
index 4a67408f44f6..3e18a2c152af 100644
--- a/drivers/serial/serial_stm32.c
+++ b/drivers/serial/serial_stm32.c
@@ -165,7 +165,7 @@ static int stm32_serial_probe(struct device *dev)
 	stm32->stm32f4 = info->stm32f4;
 	stm32->uart_enable_bit = info->uart_enable_bit;
 
-	stm32->clk = clk_get(dev, NULL);
+	stm32->clk = clk_get_for_console(dev, NULL);
 	if (IS_ERR(stm32->clk)) {
 		ret = PTR_ERR(stm32->clk);
 		dev_err(dev, "Failed to get UART clock %d\n", ret);
@@ -183,7 +183,7 @@ static int stm32_serial_probe(struct device *dev)
 	cdev->putc   = stm32_serial_putc;
 	cdev->getc   = stm32_serial_getc;
 	cdev->flush  = stm32_serial_flush;
-	cdev->setbrg = stm32_serial_setbaudrate;
+	cdev->setbrg = stm32->clk ? stm32_serial_setbaudrate : NULL;
 	cdev->linux_console_name = "ttySTM";
 
 	if (dev->of_node) {
-- 
2.39.2