From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx2.suse.de ([195.135.220.15]:46117 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753504AbdDJM7l (ORCPT ); Mon, 10 Apr 2017 08:59:41 -0400 From: Jiri Slaby To: stable@vger.kernel.org Cc: Adrian Hunter , Ulf Hansson , Jiri Slaby Subject: [patch added to 3.12-stable] mmc: sdhci: Do not disable interrupts while waiting for clock Date: Mon, 10 Apr 2017 14:58:58 +0200 Message-Id: <20170410125930.26495-21-jslaby@suse.cz> In-Reply-To: <20170410125930.26495-1-jslaby@suse.cz> References: <20170410125930.26495-1-jslaby@suse.cz> Sender: stable-owner@vger.kernel.org List-ID: From: Adrian Hunter This patch has been added to the 3.12 stable tree. If you have any objections, please let us know. =============== commit e2ebfb2142acefecc2496e71360f50d25726040b upstream. Disabling interrupts for even a millisecond can cause problems for some devices. That can happen when sdhci changes clock frequency because it waits for the clock to become stable under a spin lock. The spin lock is not necessary here. Anything that is racing with changes to the I/O state is already broken. The mmc core already provides synchronization via "claiming" the host. Although the spin lock probably should be removed from the code paths that lead to this point, such a patch would touch too much code to be suitable for stable trees. Consequently, for this patch, just drop the spin lock while waiting. Signed-off-by: Adrian Hunter Signed-off-by: Ulf Hansson Tested-by: Ludovic Desroches Signed-off-by: Jiri Slaby --- drivers/mmc/host/sdhci.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index 4e697ea67ae2..c3070ab2a05c 100644 --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -1232,7 +1232,9 @@ clock_set: return; } timeout--; - mdelay(1); + spin_unlock_irq(&host->lock); + usleep_range(900, 1100); + spin_lock_irq(&host->lock); } clk |= SDHCI_CLOCK_CARD_EN; -- 2.12.2