[PATCH] tty: xilinx_uartps: Correct return value in probe

[Rajan Vaja]

Existing driver checks for alternate clock if devm_clk_get() fails
and returns error code for last clock failure. If xilinx_uartps is
called before clock driver, devm_clk_get() returns -EPROBE_DEFER.
In this case, probe should not check for alternate clock as main
clock is already present in DTS and return -EPROBE_DEFER only.

This patch fixes it by not checking for alternate clock when main
clock get returns -EPROBE_DEFER.

Signed-off-by: Rajan Vaja <rajan.v...@xilinx.com>
---
 drivers/tty/serial/xilinx_uartps.c | 26 ++++++++++++--------------
 1 file changed, 12 insertions(+), 14 deletions(-)

diff --git a/drivers/tty/serial/xilinx_uartps.c 
b/drivers/tty/serial/xilinx_uartps.c
index 57c66d2..a23baa4 100644
--- a/drivers/tty/serial/xilinx_uartps.c
+++ b/drivers/tty/serial/xilinx_uartps.c
@@ -1545,27 +1545,25 @@ static int cdns_uart_probe(struct platform_device *pdev)
        }
 
        cdns_uart_data->pclk = devm_clk_get(&pdev->dev, "pclk");
+       if (PTR_ERR(cdns_uart_data->pclk) == -EPROBE_DEFER)
+               return PTR_ERR(cdns_uart_data->pclk);
+
        if (IS_ERR(cdns_uart_data->pclk)) {
                cdns_uart_data->pclk = devm_clk_get(&pdev->dev, "aper_clk");
-               if (!IS_ERR(cdns_uart_data->pclk))
-                       dev_err(&pdev->dev, "clock name 'aper_clk' is 
deprecated.\n");
-       }
-       if (IS_ERR(cdns_uart_data->pclk)) {
-               dev_err(&pdev->dev, "pclk clock not found.\n");
-               rc = PTR_ERR(cdns_uart_data->pclk);
-               goto err_out_unregister_driver;
+               if (IS_ERR(cdns_uart_data->pclk))
+                       return PTR_ERR(cdns_uart_data->pclk);
+               dev_err(&pdev->dev, "clock name 'aper_clk' is deprecated.\n");
        }
 
        cdns_uart_data->uartclk = devm_clk_get(&pdev->dev, "uart_clk");
+       if (PTR_ERR(cdns_uart_data->uartclk) == -EPROBE_DEFER)
+               return PTR_ERR(cdns_uart_data->uartclk);
+
        if (IS_ERR(cdns_uart_data->uartclk)) {
                cdns_uart_data->uartclk = devm_clk_get(&pdev->dev, "ref_clk");
-               if (!IS_ERR(cdns_uart_data->uartclk))
-                       dev_err(&pdev->dev, "clock name 'ref_clk' is 
deprecated.\n");
-       }
-       if (IS_ERR(cdns_uart_data->uartclk)) {
-               dev_err(&pdev->dev, "uart_clk clock not found.\n");
-               rc = PTR_ERR(cdns_uart_data->uartclk);
-               goto err_out_unregister_driver;
+               if (IS_ERR(cdns_uart_data->uartclk))
+                       return PTR_ERR(cdns_uart_data->uartclk);
+               dev_err(&pdev->dev, "clock name 'ref_clk' is deprecated.\n");
        }
 
        rc = clk_prepare_enable(cdns_uart_data->pclk);
-- 
2.7.4