Commit ffc3ae6dd "serial: 8250_dw: Enable runtime PM" introduced runtime
PM management, which enables/disables the clk without checking if the clk
is valid. However, this driver allows to be probed without a defined clk,
using clock-frequency, as a fallback.
Therefore, on platforms that are device tree probed using clock-frequency
instead of clk, we get an ugly NULL pointer dereference.
This patch fixes it by simply adding a check before accessing the clk api.
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@xxxxxxxxxxxxxxxxxx>
---
drivers/tty/serial/8250/8250_dw.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c
index beaa283..0b0eef9 100644
--- a/drivers/tty/serial/8250/8250_dw.c
+++ b/drivers/tty/serial/8250/8250_dw.c
@@ -338,7 +338,8 @@ static int dw8250_runtime_suspend(struct device *dev)
{
struct dw8250_data *data = dev_get_drvdata(dev);
- clk_disable_unprepare(data->clk);
+ if (!IS_ERR(data->clk))
+ clk_disable_unprepare(data->clk);
return 0;
}
@@ -347,7 +348,8 @@ static int dw8250_runtime_resume(struct device *dev)
{
struct dw8250_data *data = dev_get_drvdata(dev);
- clk_prepare_enable(data->clk);
+ if (!IS_ERR(data->clk))
+ clk_prepare_enable(data->clk);
return 0;
}
--
1.8.1.5
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