openwrt/target/linux/brcm2708/patches-4.19/950-0607-i2c-bcm2835-Move-IRQ-request-after-clock-code-in-pro.patch

From 614cade3a68f7214939e1c72acd5fcc9d49beeef Mon Sep 17 00:00:00 2001
From: Annaliese McDermond <nh6z@nh6z.net>
Date: Fri, 21 Jun 2019 03:52:49 -0700
Subject: [PATCH] i2c: bcm2835: Move IRQ request after clock code in
 probe

Commit 4a5cfa39465cad25dd736d7ceba8a5d32eea4ecc upstream.

If any of the clock code in the probe fails and returns, the IRQ
will not be freed.  Moving the IRQ request to last allows it to
be freed on any errors further up in the probe function.  devm_
calls can apparently not be used because there are some potential
race conditions that will arise.

Fixes: bebff81fb8b9 ("i2c: bcm2835: Model Divider in CCF")
Signed-off-by: Annaliese McDermond <nh6z@nh6z.net>
Acked-by: Stefan Wahren <wahrenst@gmx.net>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
---
 drivers/i2c/busses/i2c-bcm2835.c | 28 ++++++++++++++--------------
 1 file changed, 14 insertions(+), 14 deletions(-)

--- a/drivers/i2c/busses/i2c-bcm2835.c
+++ b/drivers/i2c/busses/i2c-bcm2835.c
@@ -521,20 +521,6 @@ static int bcm2835_i2c_probe(struct plat
 	if (IS_ERR(i2c_dev->regs))
 		return PTR_ERR(i2c_dev->regs);
 
-	irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
-	if (!irq) {
-		dev_err(&pdev->dev, "No IRQ resource\n");
-		return -ENODEV;
-	}
-	i2c_dev->irq = irq->start;
-
-	ret = request_irq(i2c_dev->irq, bcm2835_i2c_isr, IRQF_SHARED,
-			  dev_name(&pdev->dev), i2c_dev);
-	if (ret) {
-		dev_err(&pdev->dev, "Could not request IRQ\n");
-		return -ENODEV;
-	}
-
 	mclk_name = of_clk_get_parent_name(pdev->dev.of_node, 0);
 
 	bus_clk = bcm2835_i2c_register_div(&pdev->dev, mclk_name, i2c_dev);
@@ -564,6 +550,20 @@ static int bcm2835_i2c_probe(struct plat
 		return ret;
 	}
 
+	irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+	if (!irq) {
+		dev_err(&pdev->dev, "No IRQ resource\n");
+		return -ENODEV;
+	}
+	i2c_dev->irq = irq->start;
+
+	ret = request_irq(i2c_dev->irq, bcm2835_i2c_isr, IRQF_SHARED,
+			  dev_name(&pdev->dev), i2c_dev);
+	if (ret) {
+		dev_err(&pdev->dev, "Could not request IRQ\n");
+		return -ENODEV;
+	}
+
 	adap = &i2c_dev->adapter;
 	i2c_set_adapdata(adap, i2c_dev);
 	adap->owner = THIS_MODULE;