From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751757AbbAOHMf (ORCPT ); Thu, 15 Jan 2015 02:12:35 -0500 Received: from rtits2.realtek.com ([60.250.210.242]:49427 "EHLO rtits2.realtek.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751437AbbAOHMb (ORCPT ); Thu, 15 Jan 2015 02:12:31 -0500 Authenticated-By: X-SpamFilter-By: BOX Solutions SpamTrap 5.52 with qID t0F7Bo51016246, This message is accepted by code: ctloc85258 From: Roger Tseng To: Samuel Ortiz , Lee Jones CC: Greg Kroah-Hartman , , , , , Roger Tseng Subject: [PATCH 1/2] mfd: rtsx_usb: Fix runtime PM deadlock Date: Thu, 15 Jan 2015 15:14:44 +0800 Message-ID: <1421306085-32254-2-git-send-email-rogerable@realtek.com> X-Mailer: git-send-email 2.1.3 In-Reply-To: <1421306085-32254-1-git-send-email-rogerable@realtek.com> References: <1421306085-32254-1-git-send-email-rogerable@realtek.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [172.21.81.121] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org sd_set_power_mode() in derived module drivers/mmc/host/rtsx_usb_sdmmc.c acquires dev_mutex and then calls pm_runtime_get_sync() to make sure the device is awake while initializing a newly inserted card. Once it is called during suspending state and explicitly before rtsx_usb_suspend() acquires the same dev_mutex, both routine deadlock and further hang the driver because pm_runtime_get_sync() waits the pending PM operations. Fix this by using an empty suspend method. mmc_core always turns the LED off after a request is done and thus it is ok to remove the only rtsx_usb_turn_off_led() here. Cc: # v3.16+ Fixes: 730876be2566 ("mfd: Add realtek USB card reader driver") Signed-off-by: Roger Tseng --- drivers/mfd/rtsx_usb.c | 9 --------- 1 file changed, 9 deletions(-) diff --git a/drivers/mfd/rtsx_usb.c b/drivers/mfd/rtsx_usb.c index dbdd0faeb6ce..076694126e5d 100644 --- a/drivers/mfd/rtsx_usb.c +++ b/drivers/mfd/rtsx_usb.c @@ -687,15 +687,6 @@ static int rtsx_usb_suspend(struct usb_interface *intf, pm_message_t message) dev_dbg(&intf->dev, "%s called with pm message 0x%04x\n", __func__, message.event); - /* - * Call to make sure LED is off during suspend to save more power. - * It is NOT a permanent state and could be turned on anytime later. - * Thus no need to call turn_on when resunming. - */ - mutex_lock(&ucr->dev_mutex); - rtsx_usb_turn_off_led(ucr); - mutex_unlock(&ucr->dev_mutex); - return 0; } -- 2.1.3