driver core: platform: Add platform_get_irq_byname_optional()

Some drivers (e.g dwc3) first try to get an IRQ byname and then fall
back to the one at index 0. In this case we do not want the error(s)
printed by platform_get_irq_byname(). This commit adds a new
platform_get_irq_byname_optional(), which does not print errors, for this.

While at it also improve the kdoc text for platform_get_irq_byname() a bit.

BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=205037
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/r/20191005210449.3926-2-hdegoede@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index b6c6c7d97d5b2aa388baa153550ed7a4db3af022..b230beb6ccb41ba8beb5fbaf87972f69b94a33e3 100644 (file)
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -241,12 +241,8 @@ struct resource *platform_get_resource_byname(struct platform_device *dev,
 }
 EXPORT_SYMBOL_GPL(platform_get_resource_byname);
 
-/**
- * platform_get_irq_byname - get an IRQ for a device by name
- * @dev: platform device
- * @name: IRQ name
- */
-int platform_get_irq_byname(struct platform_device *dev, const char *name)
+static int __platform_get_irq_byname(struct platform_device *dev,
+                                    const char *name)
 {
        struct resource *r;
 
@@ -262,11 +258,47 @@ int platform_get_irq_byname(struct platform_device *dev, const char *name)
        if (r)
                return r->start;
 
-       dev_err(&dev->dev, "IRQ %s not found\n", name);
        return -ENXIO;
 }
+
+/**
+ * platform_get_irq_byname - get an IRQ for a device by name
+ * @dev: platform device
+ * @name: IRQ name
+ *
+ * Get an IRQ like platform_get_irq(), but then by name rather then by index.
+ *
+ * Return: IRQ number on success, negative error number on failure.
+ */
+int platform_get_irq_byname(struct platform_device *dev, const char *name)
+{
+       int ret;
+
+       ret = __platform_get_irq_byname(dev, name);
+       if (ret < 0 && ret != -EPROBE_DEFER)
+               dev_err(&dev->dev, "IRQ %s not found\n", name);
+
+       return ret;
+}
 EXPORT_SYMBOL_GPL(platform_get_irq_byname);
 
+/**
+ * platform_get_irq_byname_optional - get an optional IRQ for a device by name
+ * @dev: platform device
+ * @name: IRQ name
+ *
+ * Get an optional IRQ by name like platform_get_irq_byname(). Except that it
+ * does not print an error message if an IRQ can not be obtained.
+ *
+ * Return: IRQ number on success, negative error number on failure.
+ */
+int platform_get_irq_byname_optional(struct platform_device *dev,
+                                    const char *name)
+{
+       return __platform_get_irq_byname(dev, name);
+}
+EXPORT_SYMBOL_GPL(platform_get_irq_byname_optional);
+
 /**
  * platform_add_devices - add a numbers of platform devices
  * @devs: array of platform devices to add

diff --git a/include/linux/platform_device.h b/include/linux/platform_device.h
index 1b5cec0675335d07cf5989fa9ffe38a1351226db..f2688404d1cd73d3423d3443304a975306f4e0a1 100644 (file)
--- a/include/linux/platform_device.h
+++ b/include/linux/platform_device.h
@@ -64,6 +64,8 @@ extern struct resource *platform_get_resource_byname(struct platform_device *,
                                                     unsigned int,
                                                     const char *);
 extern int platform_get_irq_byname(struct platform_device *, const char *);
+extern int platform_get_irq_byname_optional(struct platform_device *dev,
+                                           const char *name);
 extern int platform_add_devices(struct platform_device **, int);
 
 struct platform_device_info {