serial: msm: fix clock handling and pinctrl

Use the modern helpers to fetch the clock and use the correct property
("clocks" instead of "clock"). Drop the call to pinctrl_select_state()
as no boards have a "uart" pinctrl state and this prints confusing
errors.

Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Tested-by: Sumit Garg <sumit.garg@linaro.org> #qcs404
Signed-off-by: Caleb Connolly <caleb.connolly@linaro.org>

arch/arm/dts/dragonboard410c.dts

@@ -84,7 +84,8 @@
 		serial@78b0000 {
 			compatible = "qcom,msm-uartdm-v1.4";
 			reg = <0x78b0000 0x200>;
-			clock = <&clkc 4>;
+			clocks = <&clkc 4>;
+			clock-names = "core";
 			pinctrl-names = "uart";
 			pinctrl-0 = <&blsp1_uart>;
 		};

arch/arm/dts/dragonboard820c.dts

@@ -78,7 +78,8 @@
 		blsp2_uart2: serial@75b0000 {
 			compatible = "qcom,msm-uartdm-v1.4", "qcom,msm-uartdm";
 			reg = <0x75b0000 0x1000>;
-			clock = <&gcc 4>;
+			clocks = <&gcc 4>;
+			clock-names = "core";
 			pinctrl-names = "uart";
 			pinctrl-0 = <&blsp8_uart>;
 		};

drivers/serial/serial_msm.c

@@ -160,29 +160,14 @@ static int msm_uart_clk_init(struct udevice *dev)
 {
 	uint clk_rate = fdtdec_get_uint(gd->fdt_blob, dev_of_offset(dev),
 					"clock-frequency", 115200);
-	uint clkd[2]; /* clk_id and clk_no */
-	int clk_offset;
-	struct udevice *clk_dev;
 	struct clk clk;
 	int ret;
 
-	ret = fdtdec_get_int_array(gd->fdt_blob, dev_of_offset(dev), "clock",
-				   clkd, 2);
-	if (ret)
-		return ret;
-
-	clk_offset = fdt_node_offset_by_phandle(gd->fdt_blob, clkd[0]);
-	if (clk_offset < 0)
-		return clk_offset;
-
-	ret = uclass_get_device_by_of_offset(UCLASS_CLK, clk_offset, &clk_dev);
-	if (ret)
-		return ret;
-
-	clk.id = clkd[1];
-	ret = clk_request(clk_dev, &clk);
-	if (ret < 0)
+	ret = clk_get_by_name(dev, "core", &clk);
+	if (ret < 0) {
+		pr_warn("%s: Failed to get clock: %d\n", __func__, ret);
 		return ret;
+	}
 
 	ret = clk_set_rate(&clk, clk_rate);
 	if (ret < 0)
@@ -218,7 +203,6 @@ static int msm_serial_probe(struct udevice *dev)
 	if (ret)
 		return ret;
 
-	pinctrl_select_state(dev, "uart");
 	uart_dm_init(priv);
 
 	return 0;
@@ -251,6 +235,7 @@ U_BOOT_DRIVER(serial_msm) = {
 	.priv_auto	= sizeof(struct msm_serial_data),
 	.probe = msm_serial_probe,
 	.ops	= &msm_serial_ops,
+	.flags = DM_FLAG_PRE_RELOC,
 };
 
 #ifdef CONFIG_DEBUG_UART_MSM