--- zzzz-none-000/linux-3.10.107/drivers/uio/uio_pdrv_genirq.c	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/drivers/uio/uio_pdrv_genirq.c	2021-02-04 17:41:59.000000000 +0000
@@ -37,6 +37,11 @@
 	struct platform_device *pdev;
 };
 
+/* Bits in uio_pdrv_genirq_platdata.flags */
+enum {
+	UIO_IRQ_DISABLED = 0,
+};
+
 static int uio_pdrv_genirq_open(struct uio_info *info, struct inode *inode)
 {
 	struct uio_pdrv_genirq_platdata *priv = info->priv;
@@ -63,8 +68,10 @@
 	 * remember the state so we can allow user space to enable it later.
 	 */
 
-	if (!test_and_set_bit(0, &priv->flags))
+	spin_lock(&priv->lock);
+	if (!__test_and_set_bit(UIO_IRQ_DISABLED, &priv->flags))
 		disable_irq_nosync(irq);
+	spin_unlock(&priv->lock);
 
 	return IRQ_HANDLED;
 }
@@ -78,16 +85,17 @@
 	 * in the interrupt controller, but keep track of the
 	 * state to prevent per-irq depth damage.
 	 *
-	 * Serialize this operation to support multiple tasks.
+	 * Serialize this operation to support multiple tasks and concurrency
+	 * with irq handler on SMP systems.
 	 */
 
 	spin_lock_irqsave(&priv->lock, flags);
 	if (irq_on) {
-		if (test_and_clear_bit(0, &priv->flags))
+		if (__test_and_clear_bit(UIO_IRQ_DISABLED, &priv->flags))
 			enable_irq(dev_info->irq);
 	} else {
-		if (!test_and_set_bit(0, &priv->flags))
-			disable_irq(dev_info->irq);
+		if (!__test_and_set_bit(UIO_IRQ_DISABLED, &priv->flags))
+			disable_irq_nosync(dev_info->irq);
 	}
 	spin_unlock_irqrestore(&priv->lock, flags);
 
@@ -96,49 +104,40 @@
 
 static int uio_pdrv_genirq_probe(struct platform_device *pdev)
 {
-	struct uio_info *uioinfo = pdev->dev.platform_data;
+	struct uio_info *uioinfo = dev_get_platdata(&pdev->dev);
 	struct uio_pdrv_genirq_platdata *priv;
 	struct uio_mem *uiomem;
 	int ret = -EINVAL;
 	int i;
 
 	if (pdev->dev.of_node) {
-		int irq;
-
 		/* alloc uioinfo for one device */
-		uioinfo = kzalloc(sizeof(*uioinfo), GFP_KERNEL);
+		uioinfo = devm_kzalloc(&pdev->dev, sizeof(*uioinfo),
+				       GFP_KERNEL);
 		if (!uioinfo) {
-			ret = -ENOMEM;
 			dev_err(&pdev->dev, "unable to kmalloc\n");
-			goto bad2;
+			return -ENOMEM;
 		}
 		uioinfo->name = pdev->dev.of_node->name;
 		uioinfo->version = "devicetree";
-
 		/* Multiple IRQs are not supported */
-		irq = platform_get_irq(pdev, 0);
-		if (irq == -ENXIO)
-			uioinfo->irq = UIO_IRQ_NONE;
-		else
-			uioinfo->irq = irq;
 	}
 
 	if (!uioinfo || !uioinfo->name || !uioinfo->version) {
 		dev_err(&pdev->dev, "missing platform_data\n");
-		goto bad0;
+		return ret;
 	}
 
 	if (uioinfo->handler || uioinfo->irqcontrol ||
 	    uioinfo->irq_flags & IRQF_SHARED) {
 		dev_err(&pdev->dev, "interrupt configuration error\n");
-		goto bad0;
+		return ret;
 	}
 
-	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
 	if (!priv) {
-		ret = -ENOMEM;
 		dev_err(&pdev->dev, "unable to kmalloc\n");
-		goto bad0;
+		return -ENOMEM;
 	}
 
 	priv->uioinfo = uioinfo;
@@ -148,12 +147,15 @@
 
 	if (!uioinfo->irq) {
 		ret = platform_get_irq(pdev, 0);
-		if (ret < 0) {
+		uioinfo->irq = ret;
+		if (ret == -ENXIO && pdev->dev.of_node)
+			uioinfo->irq = UIO_IRQ_NONE;
+		else if (ret < 0) {
 			dev_err(&pdev->dev, "failed to get IRQ\n");
-			goto bad0;
+			return ret;
 		}
-		uioinfo->irq = ret;
 	}
+
 	uiomem = &uioinfo->mem[0];
 
 	for (i = 0; i < pdev->num_resources; ++i) {
@@ -206,20 +208,12 @@
 	ret = uio_register_device(&pdev->dev, priv->uioinfo);
 	if (ret) {
 		dev_err(&pdev->dev, "unable to register uio device\n");
-		goto bad1;
+		pm_runtime_disable(&pdev->dev);
+		return ret;
 	}
 
 	platform_set_drvdata(pdev, priv);
 	return 0;
- bad1:
-	kfree(priv);
-	pm_runtime_disable(&pdev->dev);
- bad0:
-	/* kfree uioinfo for OF */
-	if (pdev->dev.of_node)
-		kfree(uioinfo);
- bad2:
-	return ret;
 }
 
 static int uio_pdrv_genirq_remove(struct platform_device *pdev)
@@ -232,11 +226,6 @@
 	priv->uioinfo->handler = NULL;
 	priv->uioinfo->irqcontrol = NULL;
 
-	/* kfree uioinfo for OF */
-	if (pdev->dev.of_node)
-		kfree(priv->uioinfo);
-
-	kfree(priv);
 	return 0;
 }
 
@@ -263,12 +252,13 @@
 };
 
 #ifdef CONFIG_OF
-static const struct of_device_id uio_of_genirq_match[] = {
-	{ /* empty for now */ },
+static struct of_device_id uio_of_genirq_match[] = {
+	{ /* This is filled with module_parm */ },
+	{ /* Sentinel */ },
 };
 MODULE_DEVICE_TABLE(of, uio_of_genirq_match);
-#else
-# define uio_of_genirq_match NULL
+module_param_string(of_id, uio_of_genirq_match[0].compatible, 128, 0);
+MODULE_PARM_DESC(of_id, "Openfirmware id of the device to be handled by uio");
 #endif
 
 static struct platform_driver uio_pdrv_genirq = {
@@ -276,9 +266,8 @@
 	.remove = uio_pdrv_genirq_remove,
 	.driver = {
 		.name = DRIVER_NAME,
-		.owner = THIS_MODULE,
 		.pm = &uio_pdrv_genirq_dev_pm_ops,
-		.of_match_table = uio_of_genirq_match,
+		.of_match_table = of_match_ptr(uio_of_genirq_match),
 	},
 };