watchdog: xilinx: Add clock support

Add support for the clock. Currently we enable at probe and relinquish at remove. Reviewed-by: Guenter Roeck <linux@roeck-us.net> Acked-by: Sören Brinkmann <soren.brinkmann@xilinx.com> Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>

watchdog: xilinx: Add clock support
Add support for the clock. Currently we enable at probe and relinquish at remove. Reviewed-by: Guenter Roeck <linux@roeck-us.net> Acked-by: Sören Brinkmann <soren.brinkmann@xilinx.com> Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Shubhrajyoti Datta · Wim Van Sebroeck
1 parent d2a0015174
Showing 2 changed files with 26 additions and 2 deletions Side-by-side Diff
Documentation/devicetree/bindings/watchdog/of-xilinx-wdt.txt
drivers/watchdog/of_xilinx_wdt.c
@@ -7,6 +7,8 @@
 - reg			: Physical base address and size
  
 Optional properties:
+- clocks		: Input clock specifier. Refer to common clock
+			  bindings.
 - clock-frequency	: Frequency of clock in Hz
 - xlnx,wdt-enable-once	: 0 - Watchdog can be restarted
 			  1 - Watchdog can be enabled just once
@@ -17,6 +19,7 @@
 axi-timebase-wdt@40100000 {
 	clock-frequency = <50000000>;
 	compatible = "xlnx,xps-timebase-wdt-1.00.a";
+	clocks = <&clkc 15>;
 	reg = <0x40100000 0x10000>;
 	xlnx,wdt-enable-once = <0x0>;
 	xlnx,wdt-interval = <0x1b>;
@@ -10,6 +10,7 @@
  * 2 of the License, or (at your option) any later version.
  */
  
+#include <linux/clk.h>
 #include <linux/err.h>
 #include <linux/module.h>
 #include <linux/types.h>
@@ -45,6 +46,7 @@
 	u32 wdt_interval;
 	spinlock_t spinlock;
 	struct watchdog_device xilinx_wdt_wdd;
+	struct clk		*clk;
 };
  
 static int xilinx_wdt_start(struct watchdog_device *wdd)
  
  
@@ -195,16 +197,30 @@
 	spin_lock_init(&xdev->spinlock);
 	watchdog_set_drvdata(xilinx_wdt_wdd, xdev);
  
+	xdev->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(xdev->clk)) {
+		if (PTR_ERR(xdev->clk) == -ENOENT)
+			xdev->clk = NULL;
+		else
+			return PTR_ERR(xdev->clk);
+	}
+
+	rc = clk_prepare_enable(xdev->clk);
+	if (rc) {
+		dev_err(&pdev->dev, "unable to enable clock\n");
+		return rc;
+	}
+
 	rc = xwdt_selftest(xdev);
 	if (rc == XWT_TIMER_FAILED) {
 		dev_err(&pdev->dev, "SelfTest routine error\n");
-		return rc;
+		goto err_clk_disable;
 	}
  
 	rc = watchdog_register_device(xilinx_wdt_wdd);
 	if (rc) {
 		dev_err(&pdev->dev, "Cannot register watchdog (err=%d)\n", rc);
-		return rc;
+		goto err_clk_disable;
 	}
  
 	dev_info(&pdev->dev, "Xilinx Watchdog Timer at %p with timeout %ds\n",
@@ -213,6 +229,10 @@
 	platform_set_drvdata(pdev, xdev);
  
 	return 0;
+err_clk_disable:
+	clk_disable_unprepare(xdev->clk);
+
+	return rc;
 }
  
 static int xwdt_remove(struct platform_device *pdev)
@@ -220,6 +240,7 @@
 	struct xwdt_device *xdev = platform_get_drvdata(pdev);
  
 	watchdog_unregister_device(&xdev->xilinx_wdt_wdd);
+	clk_disable_unprepare(xdev->clk);
  
 	return 0;
 }
...	...	@@ -7,6 +7,8 @@
7	7	- reg : Physical base address and size
8	8
9	9	Optional properties:
	10	+- clocks : Input clock specifier. Refer to common clock
	11	+ bindings.
10	12	- clock-frequency : Frequency of clock in Hz
11	13	- xlnx,wdt-enable-once : 0 - Watchdog can be restarted
12	14	1 - Watchdog can be enabled just once
...	...	@@ -17,6 +19,7 @@
17	19	axi-timebase-wdt@40100000 {
18	20	clock-frequency = <50000000>;
19	21	compatible = "xlnx,xps-timebase-wdt-1.00.a";
	22	+ clocks = <&clkc 15>;
20	23	reg = <0x40100000 0x10000>;
21	24	xlnx,wdt-enable-once = <0x0>;
22	25	xlnx,wdt-interval = <0x1b>;
...	...	@@ -10,6 +10,7 @@
10	10	* 2 of the License, or (at your option) any later version.
11	11	*/
12	12
	13	+#include <linux/clk.h>
13	14	#include <linux/err.h>
14	15	#include <linux/module.h>
15	16	#include <linux/types.h>
...	...	@@ -45,6 +46,7 @@
45	46	u32 wdt_interval;
46	47	spinlock_t spinlock;
47	48	struct watchdog_device xilinx_wdt_wdd;
	49	+ struct clk *clk;
48	50	};
49	51
50	52	static int xilinx_wdt_start(struct watchdog_device *wdd)
51	53
52	54
...	...	@@ -195,16 +197,30 @@
195	197	spin_lock_init(&xdev->spinlock);
196	198	watchdog_set_drvdata(xilinx_wdt_wdd, xdev);
197	199
	200	+ xdev->clk = devm_clk_get(&pdev->dev, NULL);
	201	+ if (IS_ERR(xdev->clk)) {
	202	+ if (PTR_ERR(xdev->clk) == -ENOENT)
	203	+ xdev->clk = NULL;
	204	+ else
	205	+ return PTR_ERR(xdev->clk);
	206	+ }
	207	+
	208	+ rc = clk_prepare_enable(xdev->clk);
	209	+ if (rc) {
	210	+ dev_err(&pdev->dev, "unable to enable clock\n");
	211	+ return rc;
	212	+ }
	213	+
198	214	rc = xwdt_selftest(xdev);
199	215	if (rc == XWT_TIMER_FAILED) {
200	216	dev_err(&pdev->dev, "SelfTest routine error\n");
201		- return rc;
	217	+ goto err_clk_disable;
202	218	}
203	219
204	220	rc = watchdog_register_device(xilinx_wdt_wdd);
205	221	if (rc) {
206	222	dev_err(&pdev->dev, "Cannot register watchdog (err=%d)\n", rc);
207		- return rc;
	223	+ goto err_clk_disable;
208	224	}
209	225
210	226	dev_info(&pdev->dev, "Xilinx Watchdog Timer at %p with timeout %ds\n",
...	...	@@ -213,6 +229,10 @@
213	229	platform_set_drvdata(pdev, xdev);
214	230
215	231	return 0;
	232	+err_clk_disable:
	233	+ clk_disable_unprepare(xdev->clk);
	234	+
	235	+ return rc;
216	236	}
217	237
218	238	static int xwdt_remove(struct platform_device *pdev)
...	...	@@ -220,6 +240,7 @@
220	240	struct xwdt_device *xdev = platform_get_drvdata(pdev);
221	241
222	242	watchdog_unregister_device(&xdev->xilinx_wdt_wdd);
	243	+ clk_disable_unprepare(xdev->clk);
223	244
224	245	return 0;
225	246	}