Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755167Ab2FQKM0 (ORCPT ); Sun, 17 Jun 2012 06:12:26 -0400 Received: from mail.work-microwave.de ([62.245.205.51]:49170 "EHLO work-microwave.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754615Ab2FQKMZ (ORCPT ); Sun, 17 Jun 2012 06:12:25 -0400 From: Roland Stigge To: cjb@laptop.org, grant.likely@secretlab.ca, rob.herring@calxeda.com, rmk+kernel@arm.linux.org.uk, ulf.hansson@stericsson.com, linus.walleij@linaro.org, linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org, aletes.xgr@gmail.com, linux-arm-kernel@lists.infradead.org Cc: Roland Stigge Subject: [PATCH] gpio: of_get_named_gpio_flags() return -EPROBE_DEFER if GPIO not yet available Date: Sun, 17 Jun 2012 12:11:31 +0200 Message-Id: <1339927893-8842-1-git-send-email-stigge@antcom.de> X-Mailer: git-send-email 1.7.10 X-FEAS-SYSTEM-WL: rst@work-microwave.de, 192.168.11.78 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1467 Lines: 34 of_get_named_gpio_flags() and of_get_named_gpio() return -EPROBE_DEFER if the respective GPIO is not (yet) available. This is useful if driver's probe() functions try to get a GPIO whose controller isn't probed yet. Thus, the driver can be probed again later on. The function still returns -EINVAL on other errors (parse error or node doesn't exist). This way, the case of an optional/intentionally missing GPIO is handled appropriately. Signed-off-by: Roland Stigge --- drivers/gpio/gpiolib-of.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) --- linux-2.6.orig/drivers/gpio/gpiolib-of.c +++ linux-2.6/drivers/gpio/gpiolib-of.c @@ -62,7 +62,10 @@ static int of_gpiochip_find_and_xlate(st int of_get_named_gpio_flags(struct device_node *np, const char *propname, int index, enum of_gpio_flags *flags) { - struct gg_data gg_data = { .flags = flags, .out_gpio = -ENODEV }; + /* Return -EPROBE_DEFER to support probe() functions to be called + * later when the GPIO actually becomes available + */ + struct gg_data gg_data = { .flags = flags, .out_gpio = -EPROBE_DEFER }; int ret; /* .of_xlate might decide to not fill in the flags, so clear it. */ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/