2022-03-01 07:01:19

by Yu Tu

Subject: [PATCH] tty: serial: meson: Fixed an issue where pclk was turned on on probe but should be turned off on subsequent errors.

Call clk_prepare_enable in the probe function to enable pclk. If you
exit the probe function later in an error, call clk_disable_unprepare
to disable pclk.

Fixes: 44023b8e1f14 ("tty: serial:meson: Describes the calculation of the UART baud rate clock using a clock frame“)
Reported-by: kernel test robot <[email protected]>
Reported-by: Dan Carpenter <[email protected]>
Signed-off-by: Yu Tu <[email protected]>
---
drivers/tty/serial/meson_uart.c | 37 +++++++++++++++++++++++----------
1 file changed, 26 insertions(+), 11 deletions(-)

diff --git a/drivers/tty/serial/meson_uart.c b/drivers/tty/serial/meson_uart.c
index bf6be5468aaf..972f210f3492 100644
--- a/drivers/tty/serial/meson_uart.c
+++ b/drivers/tty/serial/meson_uart.c
@@ -780,28 +780,37 @@ static int meson_uart_probe(struct platform_device *pdev)
return ret;

irq = platform_get_irq(pdev, 0);
- if (irq < 0)
- return irq;
+ if (irq < 0) {
+ ret = irq;
+ goto err_out_clk_disable;
+ }

of_property_read_u32(pdev->dev.of_node, "fifo-size", &fifosize);

if (meson_ports[pdev->id]) {
dev_err(&pdev->dev, "port %d already allocated\n", pdev->id);
- return -EBUSY;
+ ret = -EBUSY;
+ goto err_out_clk_disable;
}

port = devm_kzalloc(&pdev->dev, sizeof(struct uart_port), GFP_KERNEL);
- if (!port)
- return -ENOMEM;
+ if (!port) {
+ ret = -ENOMEM;
+ goto err_out_clk_disable;
+ }

port->membase = devm_ioremap_resource(&pdev->dev, res_mem);
- if (IS_ERR(port->membase))
- return PTR_ERR(port->membase);
+ if (IS_ERR(port->membase)) {
+ ret = PTR_ERR(port->membase);
+ goto err_out_clk_disable;
+ }

private_data = devm_kzalloc(&pdev->dev, sizeof(*private_data),
GFP_KERNEL);
- if (!private_data)
- return -ENOMEM;
+ if (!private_data) {
+ ret = -ENOMEM;
+ goto err_out_clk_disable;
+ }

if (device_get_match_data(&pdev->dev))
private_data->use_xtal_clk = true;
@@ -822,7 +831,7 @@ static int meson_uart_probe(struct platform_device *pdev)

ret = meson_uart_probe_clocks(port);
if (ret)
- return ret;
+ goto err_out_clk_disable;

meson_ports[pdev->id] = port;
platform_set_drvdata(pdev, port);
@@ -831,9 +840,15 @@ static int meson_uart_probe(struct platform_device *pdev)
meson_uart_reset(port);

ret = uart_add_one_port(&meson_uart_driver, port);
- if (ret)
+ if (ret) {
meson_ports[pdev->id] = NULL;
+ goto err_out_clk_disable;
+ }
+
+ return 0;

+err_out_clk_disable:
+ clk_disable_unprepare(pclk);
return ret;
}


base-commit: d4ab5487cc77a4053dc9070c5761ad94bf397825
--
2.33.1