Commit 29e8a0c5 authored by Wenhua Lin's avatar Wenhua Lin Committed by Greg Kroah-Hartman
Browse files

serial: sprd: Return -EPROBE_DEFER when uart clock is not ready 



In sprd_clk_init(), when devm_clk_get() returns -EPROBE_DEFER
for either uart or source clock, we should propagate the
error instead of just warning and continuing with NULL clocks.

Currently the driver only emits a warning when clock acquisition
fails and proceeds with NULL clock pointers. This can lead to
issues later when the clocks are actually needed. More importantly,
when the clock provider is not ready yet and returns -EPROBE_DEFER,
we should return this error to allow deferred probing.

This change adds explicit checks for -EPROBE_DEFER after both:
1. devm_clk_get(uport->dev, uart)
2. devm_clk_get(uport->dev, source)

When -EPROBE_DEFER is encountered, the function now returns
-EPROBE_DEFER to let the driver framework retry probing
later when the clock dependencies are resolved.

Signed-off-by: default avatarWenhua Lin <Wenhua.Lin@unisoc.com>
Link: https://patch.msgid.link/20251022030840.956589-1-Wenhua.Lin@unisoc.com


Reviewed-by: default avatarCixi Geng <cixi.geng@linux.dev>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent f0a6e936

drivers/tty/serial/sprd_serial.c

+6 −0
Original line number Diff line number Diff line
@@ -1133,6 +1133,9 @@ static int sprd_clk_init(struct uart_port *uport) 


	clk_uart = devm_clk_get(uport->dev, "uart");

	if (IS_ERR(clk_uart)) {

		if (PTR_ERR(clk_uart) == -EPROBE_DEFER)

			return -EPROBE_DEFER;



		dev_warn(uport->dev, "uart%d can't get uart clock\n",

			 uport->line);

		clk_uart = NULL;
@@ -1140,6 +1143,9 @@ static int sprd_clk_init(struct uart_port *uport) 


	clk_parent = devm_clk_get(uport->dev, "source");

	if (IS_ERR(clk_parent)) {

		if (PTR_ERR(clk_parent) == -EPROBE_DEFER)

			return -EPROBE_DEFER;



		dev_warn(uport->dev, "uart%d can't get source clock\n",

			 uport->line);

		clk_parent = NULL;