From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754216AbcFPP1x (ORCPT ); Thu, 16 Jun 2016 11:27:53 -0400 Received: from hqemgate14.nvidia.com ([216.228.121.143]:5779 "EHLO hqemgate14.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752568AbcFPP1v (ORCPT ); Thu, 16 Jun 2016 11:27:51 -0400 X-PGP-Universal: processed; by hqnvupgp08.nvidia.com on Thu, 16 Jun 2016 08:25:06 -0700 From: Jon Hunter To: Linus Walleij CC: , , Jon Hunter Subject: [PATCH V2] pinctrl: Don't create a pinctrl handle if no pinctrl entries exist Date: Thu, 16 Jun 2016 16:27:41 +0100 Message-ID: <1466090861-4538-1-git-send-email-jonathanh@nvidia.com> X-Mailer: git-send-email 2.1.4 X-NVConfidentiality: public MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When pinctrl_get() is called for a device, it will return a valid handle even if the device itself has no pinctrl state entries defined in device-tree. This is caused by the function pinctrl_dt_to_map() which will return success even if the first pinctrl state, 'pinctrl-0', is not found in the device-tree node for a device. According to the pinctrl device-tree binding documentation, pinctrl states must be numbered starting from 0 and so 'pinctrl-0' should always be present if a device uses pinctrl and therefore, if 'pinctrl-0' is not present it seems valid that we should not return a valid pinctrl handle. Fix this by returning an error code if the property 'pinctrl-0' is not present for a device. Signed-off-by: Jon Hunter --- Changes since V1: - Added of_node_put() I was wondering if this meant we are creating pinctrl handles for devices on boot that don't use pinctrl (when calling pinctrl_bind_pins()). However, although devm_pinctrl_get() does return successful for all devices, the subsequent call to pinctrl_lookup_state() (to get the default state) will fail and so we will destroy the pinctrl handle afterall. drivers/pinctrl/devicetree.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/pinctrl/devicetree.c b/drivers/pinctrl/devicetree.c index fe04e748dfe4..54dad89fc9bf 100644 --- a/drivers/pinctrl/devicetree.c +++ b/drivers/pinctrl/devicetree.c @@ -195,8 +195,13 @@ int pinctrl_dt_to_map(struct pinctrl *p) propname = kasprintf(GFP_KERNEL, "pinctrl-%d", state); prop = of_find_property(np, propname, &size); kfree(propname); - if (!prop) + if (!prop) { + if (state == 0) { + of_node_put(np); + return -ENODEV; + } break; + } list = prop->value; size /= sizeof(*list); -- 2.1.4