From: Josh Cartwright <josh.cartwright@ni.com>
Date: Mon, 21 Jan 2013 18:57:41 +0000 (+0100)
Subject: serial: xilinx_uartps: Get clock rate info from dts
X-Git-Tag: next-20130218~28^2~54
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=2326669ccbd901dffeefb66ed742c294b2e8041b;p=karo-tx-linux.git

serial: xilinx_uartps: Get clock rate info from dts

Add support for specifying clock information for the uart clk via the
device tree. This eliminates the need to hardcode rates in the device
tree.

Signed-off-by: Josh Cartwright <josh.cartwright@ni.com>
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Acked-by: Michal Simek <michal.simek@xilinx.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/arch/arm/boot/dts/zynq-7000.dtsi b/arch/arm/boot/dts/zynq-7000.dtsi
index 401c1262d4ed..5914b5654591 100644
--- a/arch/arm/boot/dts/zynq-7000.dtsi
+++ b/arch/arm/boot/dts/zynq-7000.dtsi
@@ -44,14 +44,14 @@
 			compatible = "xlnx,xuartps";
 			reg = <0xE0000000 0x1000>;
 			interrupts = <0 27 4>;
-			clock = <50000000>;
+			clocks = <&uart_clk 0>;
 		};
 
 		uart1: uart@e0001000 {
 			compatible = "xlnx,xuartps";
 			reg = <0xE0001000 0x1000>;
 			interrupts = <0 50 4>;
-			clock = <50000000>;
+			clocks = <&uart_clk 1>;
 		};
 
 		slcr: slcr@f8000000 {
diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c
index 82a3151e393c..e426603d934e 100644
--- a/drivers/tty/serial/xilinx_uartps.c
+++ b/drivers/tty/serial/xilinx_uartps.c
@@ -17,6 +17,7 @@
 #include <linux/tty.h>
 #include <linux/tty_flip.h>
 #include <linux/console.h>
+#include <linux/clk.h>
 #include <linux/irq.h>
 #include <linux/io.h>
 #include <linux/of.h>
@@ -936,16 +937,18 @@ static int xuartps_probe(struct platform_device *pdev)
 	int rc;
 	struct uart_port *port;
 	struct resource *res, *res2;
-	int clk = 0;
+	struct clk *clk;
 
-	const unsigned int *prop;
-
-	prop = of_get_property(pdev->dev.of_node, "clock", NULL);
-	if (prop)
-		clk = be32_to_cpup(prop);
-	if (!clk) {
+	clk = of_clk_get(pdev->dev.of_node, 0);
+	if (IS_ERR(clk)) {
 		dev_err(&pdev->dev, "no clock specified\n");
-		return -ENODEV;
+		return PTR_ERR(clk);
+	}
+
+	rc = clk_prepare_enable(clk);
+	if (rc) {
+		dev_err(&pdev->dev, "could not enable clock\n");
+		return -EBUSY;
 	}
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -970,7 +973,8 @@ static int xuartps_probe(struct platform_device *pdev)
 		port->mapbase = res->start;
 		port->irq = res2->start;
 		port->dev = &pdev->dev;
-		port->uartclk = clk;
+		port->uartclk = clk_get_rate(clk);
+		port->private_data = clk;
 		dev_set_drvdata(&pdev->dev, port);
 		rc = uart_add_one_port(&xuartps_uart_driver, port);
 		if (rc) {
@@ -992,14 +996,14 @@ static int xuartps_probe(struct platform_device *pdev)
 static int xuartps_remove(struct platform_device *pdev)
 {
 	struct uart_port *port = dev_get_drvdata(&pdev->dev);
-	int rc = 0;
+	struct clk *clk = port->private_data;
+	int rc;
 
 	/* Remove the xuartps port from the serial core */
-	if (port) {
-		rc = uart_remove_one_port(&xuartps_uart_driver, port);
-		dev_set_drvdata(&pdev->dev, NULL);
-		port->mapbase = 0;
-	}
+	rc = uart_remove_one_port(&xuartps_uart_driver, port);
+	dev_set_drvdata(&pdev->dev, NULL);
+	port->mapbase = 0;
+	clk_disable_unprepare(clk);
 	return rc;
 }