From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rob Herring Subject: [PATCH 1/3] of/irq: of_irq_find_parent: check for parent equal to child Date: Tue, 20 Sep 2011 15:24:02 -0500 Message-ID: <1316550244-3655-2-git-send-email-robherring2@gmail.com> References: <1316550244-3655-1-git-send-email-robherring2@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1316550244-3655-1-git-send-email-robherring2-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: devicetree-discuss-bounces+gldd-devicetree-discuss=m.gmane.org-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org Sender: devicetree-discuss-bounces+gldd-devicetree-discuss=m.gmane.org-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org To: linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Cc: dave.martin-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org, linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org, Rob Herring List-Id: devicetree@vger.kernel.org From: Rob Herring An interrupt controller may often implicitly inherit itself from a parent node when in fact the controller is the interrupt root controller. Guard against the case of child == parent and return NULL in this case. This can also be fixed by adding an explicit "interrupt-parent;" to a root interrupt controller node. Based on code from Grant Likely. Signed-off-by: Rob Herring Cc: Grant Likely --- drivers/of/irq.c | 14 +++++++------- 1 files changed, 7 insertions(+), 7 deletions(-) diff --git a/drivers/of/irq.c b/drivers/of/irq.c index 9f689f1..6a5b5e7 100644 --- a/drivers/of/irq.c +++ b/drivers/of/irq.c @@ -58,27 +58,27 @@ EXPORT_SYMBOL_GPL(irq_of_parse_and_map); */ struct device_node *of_irq_find_parent(struct device_node *child) { - struct device_node *p; + struct device_node *p, *c = child; const __be32 *parp; - if (!of_node_get(child)) + if (!of_node_get(c)) return NULL; do { - parp = of_get_property(child, "interrupt-parent", NULL); + parp = of_get_property(c, "interrupt-parent", NULL); if (parp == NULL) - p = of_get_parent(child); + p = of_get_parent(c); else { if (of_irq_workarounds & OF_IMAP_NO_PHANDLE) p = of_node_get(of_irq_dflt_pic); else p = of_find_node_by_phandle(be32_to_cpup(parp)); } - of_node_put(child); - child = p; + of_node_put(c); + c = p; } while (p && of_get_property(p, "#interrupt-cells", NULL) == NULL); - return p; + return (p == child) ? NULL : p; } /** -- 1.7.5.4