serial: sh-sci: Use devm_clk_get_optional()

The sh-sci driver supports up to four input clocks, of which only the
first one is mandatory.

Replace devm_clk_get() and custom error checking by
devm_clk_get_optional(), to simplify the code and to catch all real
errors.

Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/bce27288cb570952dd96b441e1af8768ad8b4870.1639663832.git.geert+renesas@glider.be
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
index 9b4afbb3f67c2d6d8f46d9fb7ab6fe66a7a1f984..c9073ba3b8daf8fd5013b0d6be443909c254798a 100644 (file)
--- a/drivers/tty/serial/sh-sci.c
+++ b/drivers/tty/serial/sh-sci.c
@@ -2779,11 +2779,11 @@ static int sci_init_clocks(struct sci_port *sci_port, struct device *dev)
                clk_names[SCI_SCK] = "hsck";
 
        for (i = 0; i < SCI_NUM_CLKS; i++) {
-               clk = devm_clk_get(dev, clk_names[i]);
-               if (PTR_ERR(clk) == -EPROBE_DEFER)
-                       return -EPROBE_DEFER;
+               clk = devm_clk_get_optional(dev, clk_names[i]);
+               if (IS_ERR(clk))
+                       return PTR_ERR(clk);
 
-               if (IS_ERR(clk) && i == SCI_FCK) {
+               if (!clk && i == SCI_FCK) {
                        /*
                         * Not all SH platforms declare a clock lookup entry
                         * for SCI devices, in which case we need to get the
@@ -2796,13 +2796,12 @@ static int sci_init_clocks(struct sci_port *sci_port, struct device *dev)
                                                     clk_names[i]);
                }
 
-               if (IS_ERR(clk))
-                       dev_dbg(dev, "failed to get %s (%ld)\n", clk_names[i],
-                               PTR_ERR(clk));
+               if (!clk)
+                       dev_dbg(dev, "failed to get %s\n", clk_names[i]);
                else
                        dev_dbg(dev, "clk %s is %pC rate %lu\n", clk_names[i],
                                clk, clk_get_rate(clk));
-               sci_port->clks[i] = IS_ERR(clk) ? NULL : clk;
+               sci_port->clks[i] = clk;
        }
        return 0;
 }