Xilinx: ARM: xuartps: Error handling

Using clk_prepare_enable() and clk_disable_unprepare() in favor of
calling (un)prepare and dis/enable routines individually.
Honoring clk_prepare_enable() return code to recognize an error.

Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com>

diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c
index 2ab0e58a405bec2467776f0e3d54c71c80b15202..f3a922f0f0fe143e8df8ed7fe05e9364c9542326 100644 (file)
--- a/drivers/tty/serial/xilinx_uartps.c
+++ b/drivers/tty/serial/xilinx_uartps.c
@@ -1259,29 +1259,36 @@ static int __devinit xuartps_probe(struct platform_device *pdev)
                xuartps->uartnum = 0;
        else
                xuartps->uartnum = 1;
-       if (xuartps->uartnum) {
-               xuartps->devclk = clk_get_sys("UART1", NULL);
+
+       if (xuartps->uartnum)
                xuartps->aperclk = clk_get_sys("UART1_APER", NULL);
-       } else {
-               xuartps->devclk = clk_get_sys("UART0", NULL);
+       else
                xuartps->aperclk = clk_get_sys("UART0_APER", NULL);
+       if (IS_ERR(xuartps->aperclk)) {
+               pr_err("Xilinx UARTPS APER clock not found.\n");
+               ret = PTR_ERR(xuartps->aperclk);
+               goto err_out_free;
        }
-
+       if (xuartps->uartnum)
+               xuartps->devclk = clk_get_sys("UART1", NULL);
+       else
+               xuartps->devclk = clk_get_sys("UART0", NULL);
        if (IS_ERR(xuartps->devclk)) {
                pr_err("Xilinx UARTPS device clock not found.\n");
-               ret = -ENODEV;
-               goto err_out;
-       }
-       if (IS_ERR(xuartps->aperclk)) {
-               pr_err("Xilinx UARTPS APER clock not found.\n");
-               ret = -ENODEV;
-               goto err_out;
+               ret = PTR_ERR(xuartps->devclk);
+               goto err_out_clk_put_aper;
        }
 
-       clk_prepare(xuartps->aperclk);
-       clk_enable(xuartps->aperclk);
-       clk_prepare(xuartps->devclk);
-       clk_enable(xuartps->devclk);
+       ret = clk_prepare_enable(xuartps->aperclk);
+       if (ret) {
+               pr_err("Xilinx UARTPS unable to enable APER clock.\n");
+               goto err_out_clk_put;
+       }
+       ret = clk_prepare_enable(xuartps->devclk);
+       if (ret) {
+               pr_err("Xilinx UARTPS unable to enable device clock.\n");
+               goto err_out_clk_dis_aper;
+       }
 
        clk = (unsigned int)clk_get_rate(xuartps->devclk);
        xuartps->clk_rate_change_nb.notifier_call = xuartps_clk_notifier_cb;
@@ -1295,7 +1302,7 @@ static int __devinit xuartps_probe(struct platform_device *pdev)
        if (!port) {
                dev_err(&pdev->dev, "Cannot get uart_port structure\n");
                ret = -ENODEV;
-               goto err_out2;
+               goto err_out_clk_dis;
        } else {
                /* Register the port.
                 * This function also registers this device with the tty layer
@@ -1320,21 +1327,21 @@ static int __devinit xuartps_probe(struct platform_device *pdev)
                        xuartps->port = NULL;
                        ret = rc;
 #endif
-                       goto err_out2;
+                       goto err_out_clk_dis;
                }
                return 0;
        }
-err_out2:
+err_out_clk_dis:
 #ifdef CONFIG_COMMON_CLK
-       clk_disable(xuartps->devclk);
-       clk_unprepare(xuartps->devclk);
+       clk_notifier_unregister(xuartps->devclk, &xuartps->clk_rate_change_nb);
+       clk_disable_unprepare(xuartps->devclk);
+err_out_clk_dis_aper:
+       clk_disable_unprepare(xuartps->aperclk);
+err_out_clk_put:
        clk_put(xuartps->devclk);
-       clk_disable(xuartps->aperclk);
-       clk_unprepare(xuartps->aperclk);
+err_out_clk_put_aper:
        clk_put(xuartps->aperclk);
-#endif
-#ifdef CONFIG_COMMON_CLK
-err_out:
+err_out_free:
        kfree(xuartps);
 #endif
 
@@ -1368,11 +1375,9 @@ static int __devexit xuartps_remove(struct platform_device *pdev)
                dev_set_drvdata(&pdev->dev, NULL);
                port->mapbase = 0;
 #ifdef CONFIG_COMMON_CLK
-               clk_disable(xuartps->devclk);
-               clk_unprepare(xuartps->devclk);
+               clk_disable_unprepare(xuartps->devclk);
                clk_put(xuartps->devclk);
-               clk_disable(xuartps->aperclk);
-               clk_unprepare(xuartps->aperclk);
+               clk_disable_unprepare(xuartps->aperclk);
                clk_put(xuartps->aperclk);
                kfree(xuartps);
 #endif