diff mbox

[3.13.y.z,extended,stable] Patch "of/irq: do irq resolution in platform_get_irq" has been added to staging queue

Message ID 1402426907-6162-1-git-send-email-kamal@canonical.com
State New
Headers show

Commit Message

Kamal Mostafa June 10, 2014, 7:01 p.m. UTC
This is a note to let you know that I have just added a patch titled

    of/irq: do irq resolution in platform_get_irq

to the linux-3.13.y-queue branch of the 3.13.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.13.y-queue

This patch is scheduled to be released in version 3.13.11.3.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.13.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

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From c05c9ff16450bde6d8fd3dcd0f927bfcb1e429e0 Mon Sep 17 00:00:00 2001
From: Rob Herring <robh@kernel.org>
Date: Wed, 23 Apr 2014 17:57:41 -0500
Subject: of/irq: do irq resolution in platform_get_irq

commit 9ec36cafe43bf835f8f29273597a5b0cbc8267ef upstream.

Currently we get the following kind of errors if we try to use interrupt
phandles to irqchips that have not yet initialized:

irq: no irq domain found for /ocp/pinmux@48002030 !
------------[ cut here ]------------
WARNING: CPU: 0 PID: 1 at drivers/of/platform.c:171 of_device_alloc+0x144/0x184()
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.12.0-00038-g42a9708 #1012
(show_stack+0x14/0x1c)
(dump_stack+0x6c/0xa0)
(warn_slowpath_common+0x64/0x84)
(warn_slowpath_null+0x1c/0x24)
(of_device_alloc+0x144/0x184)
(of_platform_device_create_pdata+0x44/0x9c)
(of_platform_bus_create+0xd0/0x170)
(of_platform_bus_create+0x12c/0x170)
(of_platform_populate+0x60/0x98)

This is because we're wrongly trying to populate resources that are not
yet available. It's perfectly valid to create irqchips dynamically, so
let's fix up the issue by resolving the interrupt resources when
platform_get_irq is called.

And then we also need to accept the fact that some irqdomains do not
exist that early on, and only get initialized later on. So we can
make the current WARN_ON into just into a pr_debug().

We still attempt to populate irq resources when we create the devices.
This allows current drivers which don't use platform_get_irq to continue
to function. Once all drivers are fixed, this code can be removed.

Suggested-by: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
---
 drivers/base/platform.c |  7 ++++++-
 drivers/of/irq.c        | 26 ++++++++++++++++++++++++++
 drivers/of/platform.c   |  4 +++-
 include/linux/of_irq.h  |  5 +++++
 4 files changed, 40 insertions(+), 2 deletions(-)

--
1.9.1
diff mbox

Patch

diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index 3a94b79..39d2f6b 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -13,6 +13,7 @@ 
 #include <linux/string.h>
 #include <linux/platform_device.h>
 #include <linux/of_device.h>
+#include <linux/of_irq.h>
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/dma-mapping.h>
@@ -87,7 +88,11 @@  int platform_get_irq(struct platform_device *dev, unsigned int num)
 		return -ENXIO;
 	return dev->archdata.irqs[num];
 #else
-	struct resource *r = platform_get_resource(dev, IORESOURCE_IRQ, num);
+	struct resource *r;
+	if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node)
+		return of_irq_get(dev->dev.of_node, num);
+
+	r = platform_get_resource(dev, IORESOURCE_IRQ, num);

 	return r ? r->start : -ENXIO;
 #endif
diff --git a/drivers/of/irq.c b/drivers/of/irq.c
index 2721240..11c7f73 100644
--- a/drivers/of/irq.c
+++ b/drivers/of/irq.c
@@ -377,6 +377,32 @@  int of_irq_to_resource(struct device_node *dev, int index, struct resource *r)
 EXPORT_SYMBOL_GPL(of_irq_to_resource);

 /**
+ * of_irq_get - Decode a node's IRQ and return it as a Linux irq number
+ * @dev: pointer to device tree node
+ * @index: zero-based index of the irq
+ *
+ * Returns Linux irq number on success, or -EPROBE_DEFER if the irq domain
+ * is not yet created.
+ *
+ */
+int of_irq_get(struct device_node *dev, int index)
+{
+	int rc;
+	struct of_phandle_args oirq;
+	struct irq_domain *domain;
+
+	rc = of_irq_parse_one(dev, index, &oirq);
+	if (rc)
+		return rc;
+
+	domain = irq_find_host(oirq.np);
+	if (!domain)
+		return -EPROBE_DEFER;
+
+	return irq_create_of_mapping(&oirq);
+}
+
+/**
  * of_irq_count - Count the number of IRQs a node uses
  * @dev: pointer to device tree node
  */
diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index 404d1da..bd47fbc 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -168,7 +168,9 @@  struct platform_device *of_device_alloc(struct device_node *np,
 			rc = of_address_to_resource(np, i, res);
 			WARN_ON(rc);
 		}
-		WARN_ON(of_irq_to_resource_table(np, res, num_irq) != num_irq);
+		if (of_irq_to_resource_table(np, res, num_irq) != num_irq)
+			pr_debug("not all legacy IRQ resources mapped for %s\n",
+				 np->name);
 	}

 	dev->dev.of_node = of_node_get(np);
diff --git a/include/linux/of_irq.h b/include/linux/of_irq.h
index 3f23b44..6404253 100644
--- a/include/linux/of_irq.h
+++ b/include/linux/of_irq.h
@@ -44,11 +44,16 @@  extern void of_irq_init(const struct of_device_id *matches);

 #ifdef CONFIG_OF_IRQ
 extern int of_irq_count(struct device_node *dev);
+extern int of_irq_get(struct device_node *dev, int index);
 #else
 static inline int of_irq_count(struct device_node *dev)
 {
 	return 0;
 }
+static inline int of_irq_get(struct device_node *dev, int index)
+{
+	return 0;
+}
 #endif

 #if defined(CONFIG_OF)