From 29e8a0c587e328ed458380a45d6028adf64d7487 Mon Sep 17 00:00:00 2001 From: Wenhua Lin Date: Wed, 22 Oct 2025 11:08:40 +0800 Subject: [PATCH] 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: Wenhua Lin Link: https://patch.msgid.link/20251022030840.956589-1-Wenhua.Lin@unisoc.com Reviewed-by: Cixi Geng Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/sprd_serial.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/tty/serial/sprd_serial.c b/drivers/tty/serial/sprd_serial.c index 8c9366321f8e7..092755f356836 100644 --- a/drivers/tty/serial/sprd_serial.c +++ b/drivers/tty/serial/sprd_serial.c @@ -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; -- 2.47.3