watchdog: xilinx: Allocate private structure per device

Only one watchdog could be used by this driver.
Create driver private data structure and move there
all variables for one instance.
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>

drivers/watchdog/of_xilinx_wdt.c

@@ -46,30 +46,27 @@
 struct xwdt_device {
 	void __iomem *base;
 	u32 wdt_interval;
+	spinlock_t spinlock;
+	struct watchdog_device xilinx_wdt_wdd;
 };
 
-static struct xwdt_device xdev;
-
-static  u32 timeout;
-
-static  DEFINE_SPINLOCK(spinlock);
-
 static int xilinx_wdt_start(struct watchdog_device *wdd)
 {
 	u32 control_status_reg;
+	struct xwdt_device *xdev = watchdog_get_drvdata(wdd);
 
-	spin_lock(&spinlock);
+	spin_lock(&xdev->spinlock);
 
 	/* Clean previous status and enable the watchdog timer */
-	control_status_reg = ioread32(xdev.base + XWT_TWCSR0_OFFSET);
+	control_status_reg = ioread32(xdev->base + XWT_TWCSR0_OFFSET);
 	control_status_reg |= (XWT_CSR0_WRS_MASK | XWT_CSR0_WDS_MASK);
 
 	iowrite32((control_status_reg | XWT_CSR0_EWDT1_MASK),
-				xdev.base + XWT_TWCSR0_OFFSET);
+		  xdev->base + XWT_TWCSR0_OFFSET);
 
-	iowrite32(XWT_CSRX_EWDT2_MASK, xdev.base + XWT_TWCSR1_OFFSET);
+	iowrite32(XWT_CSRX_EWDT2_MASK, xdev->base + XWT_TWCSR1_OFFSET);
 
-	spin_unlock(&spinlock);
+	spin_unlock(&xdev->spinlock);
 
 	return 0;
 }
@@ -77,17 +74,18 @@ static int xilinx_wdt_start(struct watchdog_device *wdd)
 static int xilinx_wdt_stop(struct watchdog_device *wdd)
 {
 	u32 control_status_reg;
+	struct xwdt_device *xdev = watchdog_get_drvdata(wdd);
 
-	spin_lock(&spinlock);
+	spin_lock(&xdev->spinlock);
 
-	control_status_reg = ioread32(xdev.base + XWT_TWCSR0_OFFSET);
+	control_status_reg = ioread32(xdev->base + XWT_TWCSR0_OFFSET);
 
 	iowrite32((control_status_reg & ~XWT_CSR0_EWDT1_MASK),
-				xdev.base + XWT_TWCSR0_OFFSET);
+		  xdev->base + XWT_TWCSR0_OFFSET);
 
-	iowrite32(0, xdev.base + XWT_TWCSR1_OFFSET);
+	iowrite32(0, xdev->base + XWT_TWCSR1_OFFSET);
 
-	spin_unlock(&spinlock);
+	spin_unlock(&xdev->spinlock);
 	pr_info("Stopped!\n");
 
 	return 0;
@@ -96,14 +94,15 @@ static int xilinx_wdt_stop(struct watchdog_device *wdd)
 static int xilinx_wdt_keepalive(struct watchdog_device *wdd)
 {
 	u32 control_status_reg;
+	struct xwdt_device *xdev = watchdog_get_drvdata(wdd);
 
-	spin_lock(&spinlock);
+	spin_lock(&xdev->spinlock);
 
-	control_status_reg = ioread32(xdev.base + XWT_TWCSR0_OFFSET);
+	control_status_reg = ioread32(xdev->base + XWT_TWCSR0_OFFSET);
 	control_status_reg |= (XWT_CSR0_WRS_MASK | XWT_CSR0_WDS_MASK);
-	iowrite32(control_status_reg, xdev.base + XWT_TWCSR0_OFFSET);
+	iowrite32(control_status_reg, xdev->base + XWT_TWCSR0_OFFSET);
 
-	spin_unlock(&spinlock);
+	spin_unlock(&xdev->spinlock);
 
 	return 0;
 }
@@ -122,29 +121,24 @@ static const struct watchdog_ops xilinx_wdt_ops = {
 	.ping = xilinx_wdt_keepalive,
 };
 
-static struct watchdog_device xilinx_wdt_wdd = {
-	.info = &xilinx_wdt_ident,
-	.ops = &xilinx_wdt_ops,
-};
-
-static u32 xwdt_selftest(void)
+static u32 xwdt_selftest(struct xwdt_device *xdev)
 {
 	int i;
 	u32 timer_value1;
 	u32 timer_value2;
 
-	spin_lock(&spinlock);
+	spin_lock(&xdev->spinlock);
 
-	timer_value1 = ioread32(xdev.base + XWT_TBR_OFFSET);
-	timer_value2 = ioread32(xdev.base + XWT_TBR_OFFSET);
+	timer_value1 = ioread32(xdev->base + XWT_TBR_OFFSET);
+	timer_value2 = ioread32(xdev->base + XWT_TBR_OFFSET);
 
 	for (i = 0;
 		((i <= XWT_MAX_SELFTEST_LOOP_COUNT) &&
 			(timer_value2 == timer_value1)); i++) {
-		timer_value2 = ioread32(xdev.base + XWT_TBR_OFFSET);
+		timer_value2 = ioread32(xdev->base + XWT_TBR_OFFSET);
 	}
 
-	spin_unlock(&spinlock);
+	spin_unlock(&xdev->spinlock);
 
 	if (timer_value2 != timer_value1)
 		return ~XWT_TIMER_FAILED;
@@ -158,12 +152,23 @@ static int xwdt_probe(struct platform_device *pdev)
 	u32 *tmptr;
 	u32 *pfreq;
 	struct resource *res;
+	struct xwdt_device *xdev;
 	bool no_timeout = false;
+	struct watchdog_device *xilinx_wdt_wdd;
+
+	xdev = devm_kzalloc(&pdev->dev, sizeof(*xdev), GFP_KERNEL);
+	if (!xdev)
+		return -ENOMEM;
+
+	xilinx_wdt_wdd = &xdev->xilinx_wdt_wdd;
+	xilinx_wdt_wdd->info = &xilinx_wdt_ident;
+	xilinx_wdt_wdd->ops = &xilinx_wdt_ops;
+	xilinx_wdt_wdd->parent = &pdev->dev;
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	xdev.base = devm_ioremap_resource(&pdev->dev, res);
-	if (IS_ERR(xdev.base))
-		return PTR_ERR(xdev.base);
+	xdev->base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(xdev->base))
+		return PTR_ERR(xdev->base);
 
 	pfreq = (u32 *)of_get_property(pdev->dev.of_node,
 					"clock-frequency", NULL);
@@ -179,14 +184,14 @@ static int xwdt_probe(struct platform_device *pdev)
 		pr_warn("Parameter \"xlnx,wdt-interval\" not found in device tree!\n");
 		no_timeout = true;
 	} else {
-		xdev.wdt_interval = *tmptr;
+		xdev->wdt_interval = *tmptr;
 	}
 
 	tmptr = (u32 *)of_get_property(pdev->dev.of_node,
 					"xlnx,wdt-enable-once", NULL);
 	if (tmptr == NULL) {
 		pr_warn("Parameter \"xlnx,wdt-enable-once\" not found in device tree!\n");
-		watchdog_set_nowayout(&xilinx_wdt_wdd, true);
+		watchdog_set_nowayout(xilinx_wdt_wdd, true);
 	}
 
 /*
@@ -194,29 +199,37 @@ static int xwdt_probe(struct platform_device *pdev)
  *  ignored (interrupt), reset is only generated at second wdt overflow
  */
 	if (!no_timeout)
-		timeout = 2 * ((1<<xdev.wdt_interval) / *pfreq);
+		xilinx_wdt_wdd->timeout = 2 * ((1 << xdev->wdt_interval) /
+					  *pfreq);
+
+	spin_lock_init(&xdev->spinlock);
+	watchdog_set_drvdata(xilinx_wdt_wdd, xdev);
 
-	rc = xwdt_selftest();
+	rc = xwdt_selftest(xdev);
 	if (rc == XWT_TIMER_FAILED) {
 		pr_err("SelfTest routine error!\n");
 		return rc;
 	}
 
-	rc = watchdog_register_device(&xilinx_wdt_wdd);
+	rc = watchdog_register_device(xilinx_wdt_wdd);
 	if (rc) {
 		pr_err("cannot register watchdog (err=%d)\n", rc);
 		return rc;
 	}
 
 	dev_info(&pdev->dev, "Xilinx Watchdog Timer at %p with timeout %ds\n",
-		 xdev.base, timeout);
+		 xdev->base, xilinx_wdt_wdd->timeout);
+
+	platform_set_drvdata(pdev, xdev);
 
 	return 0;
 }
 
-static int xwdt_remove(struct platform_device *dev)
+static int xwdt_remove(struct platform_device *pdev)
 {
-	watchdog_unregister_device(&xilinx_wdt_wdd);
+	struct xwdt_device *xdev = platform_get_drvdata(pdev);
+
+	watchdog_unregister_device(&xdev->xilinx_wdt_wdd);
 
 	return 0;
 }