Patch "drivers: fwnode: fix fwnode_irq_get[_byname]()" has been added to the 6.4-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    drivers: fwnode: fix fwnode_irq_get[_byname]()

to the 6.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     drivers-fwnode-fix-fwnode_irq_get-_byname.patch
and it can be found in the queue-6.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit d972f07d6a0689c8dfb2dc9b7da1c17d968d80c2
Author: Matti Vaittinen <mazziesaccount@xxxxxxxxx>
Date:   Mon May 29 09:22:33 2023 +0300

    drivers: fwnode: fix fwnode_irq_get[_byname]()
    
    [ Upstream commit 39d422555e43379516d4d13f5b7162a3dee6e646 ]
    
    The fwnode_irq_get() and the fwnode_irq_get_byname() return 0 upon
    device-tree IRQ mapping failure. This is contradicting the
    fwnode_irq_get_byname() function documentation and can potentially be a
    source of errors like:
    
    int probe(...) {
            ...
    
            irq = fwnode_irq_get_byname();
            if (irq <= 0)
                    return irq;
    
            ...
    }
    
    Here we do correctly check the return value from fwnode_irq_get_byname()
    but the driver probe will now return success. (There was already one
    such user in-tree).
    
    Change the fwnode_irq_get_byname() to work as documented and make also the
    fwnode_irq_get() follow same common convention returning a negative errno
    upon failure.
    
    Fixes: ca0acb511c21 ("device property: Add fwnode_irq_get_byname")
    Suggested-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
    Suggested-by: Jonathan Cameron <jic23@xxxxxxxxxx>
    Signed-off-by: Matti Vaittinen <mazziesaccount@xxxxxxxxx>
    Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
    Reviewed-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
    
    Message-ID: <3e64fe592dc99e27ef9a0b247fc49fa26b6b8a58.1685340157.git.mazziesaccount@xxxxxxxxx>
    Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/base/property.c b/drivers/base/property.c
index f6117ec9805c4..8c40abed78524 100644
--- a/drivers/base/property.c
+++ b/drivers/base/property.c
@@ -987,12 +987,18 @@ EXPORT_SYMBOL(fwnode_iomap);
  * @fwnode:	Pointer to the firmware node
  * @index:	Zero-based index of the IRQ
  *
- * Return: Linux IRQ number on success. Other values are determined
- * according to acpi_irq_get() or of_irq_get() operation.
+ * Return: Linux IRQ number on success. Negative errno on failure.
  */
 int fwnode_irq_get(const struct fwnode_handle *fwnode, unsigned int index)
 {
-	return fwnode_call_int_op(fwnode, irq_get, index);
+	int ret;
+
+	ret = fwnode_call_int_op(fwnode, irq_get, index);
+	/* We treat mapping errors as invalid case */
+	if (ret == 0)
+		return -EINVAL;
+
+	return ret;
 }
 EXPORT_SYMBOL(fwnode_irq_get);