Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756576AbcJNTjV (ORCPT ); Fri, 14 Oct 2016 15:39:21 -0400 Received: from ramses-pyramidenbau.de ([37.120.178.10]:57474 "EHLO mail.ramses-pyramidenbau.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750929AbcJNTjO (ORCPT ); Fri, 14 Oct 2016 15:39:14 -0400 X-Greylist: delayed 451 seconds by postgrey-1.27 at vger.kernel.org; Fri, 14 Oct 2016 15:39:13 EDT From: Ralf Ramsauer To: Mark Brown , linux-spi@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Ralf Ramsauer , Geert Uytterhoeven Subject: [PATCH] spi: mark device nodes only in case of successful instantiation Date: Fri, 14 Oct 2016 21:31:13 +0200 Message-Id: <20161014193113.29275-1-ralf@ramses-pyramidenbau.de> X-Mailer: git-send-email 2.10.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1917 Lines: 59 Instantiated SPI device nodes are marked with OF_POPULATE. This was introduced in bd6c164. On unloading, loaded device nodes will of course be unmarked. The problem are nodes the fail during initialisation: If a node failed during registration, it won't be unloaded and hence never be unmarked again. So if a SPI driver module is unloaded and reloaded, it will skip nodes that failed before. Skip device nodes that are already populated and mark them only in case of success. Fixes: bd6c164 ("spi: Mark instantiated device nodes with OF_POPULATE") Signed-off-by: Ralf Ramsauer Cc: Geert Uytterhoeven --- Hi, imagine the following situation: you loaded a spi driver as module, but it fails to instantiate, because of some reasons (e.g. some resources, like gpios, might be in use in userspace). When reloading the driver, _all_ nodes, including previously failed ones, should be probed again. This is not the case at the moment. Current behaviour only re-registers nodes that were previously successfully loaded. This small patches fixes this behaviour. I stumbled over this while working on a spi driver. Ralf drivers/spi/spi.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 200ca22..f96a04e 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -1604,12 +1604,15 @@ static void of_register_spi_devices(struct spi_master *master) return; for_each_available_child_of_node(master->dev.of_node, nc) { - if (of_node_test_and_set_flag(nc, OF_POPULATED)) + if (of_node_check_flag(nc, OF_POPULATED)) continue; spi = of_register_spi_device(master, nc); - if (IS_ERR(spi)) + if (IS_ERR(spi)) { dev_warn(&master->dev, "Failed to create SPI device for %s\n", nc->full_name); + continue; + } + of_node_set_flag(nc, OF_POPULATED); } } #else -- 2.10.1