From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]:33534 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S968108AbeEXJyC (ORCPT ); Thu, 24 May 2018 05:54:02 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Yoshihiro Shimoda , Mathias Nyman , Sasha Levin Subject: [PATCH 4.14 063/165] usb: host: xhci-plat: revert "usb: host: xhci-plat: enable clk in resume timing" Date: Thu, 24 May 2018 11:37:49 +0200 Message-Id: <20180524093624.571694301@linuxfoundation.org> In-Reply-To: <20180524093621.979359379@linuxfoundation.org> References: <20180524093621.979359379@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Yoshihiro Shimoda [ Upstream commit d56e57ca030c8b4296944a2ae61ac167bf979c07 ] This patch reverts the commit 835e4241e714 ("usb: host: xhci-plat: enable clk in resume timing") because this driver also has runtime PM and the commit 560869100b99 ("clk: renesas: cpg-mssr: Restore module clocks during resume") will restore the clock on R-Car H3 environment. If the xhci_plat_suspend() disables the clk, the system cannot enable the clk in resume like the following behavior: < In resume > - genpd_resume_noirq() runs and enable the clk (enable_count = 1) - cpg_mssr_resume_noirq() restores the clk register. -- Since the clk was disabled in suspend, cpg_mssr_resume_noirq() will disable the clk and keep the enable_count. - Even if xhci_plat_resume() calls clk_prepare_enable(), since the enable_count is 1, the clk will be not enabled. After this patch is applied, the cpg-mssr driver will save the clk as enable, so the clk will be enabled in resume. Fixes: 835e4241e714 ("usb: host: xhci-plat: enable clk in resume timing") Signed-off-by: Yoshihiro Shimoda Signed-off-by: Mathias Nyman Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/xhci-plat.c | 11 +---------- 1 file changed, 1 insertion(+), 10 deletions(-) --- a/drivers/usb/host/xhci-plat.c +++ b/drivers/usb/host/xhci-plat.c @@ -355,7 +355,6 @@ static int __maybe_unused xhci_plat_susp { struct usb_hcd *hcd = dev_get_drvdata(dev); struct xhci_hcd *xhci = hcd_to_xhci(hcd); - int ret; /* * xhci_suspend() needs `do_wakeup` to know whether host is allowed @@ -365,12 +364,7 @@ static int __maybe_unused xhci_plat_susp * reconsider this when xhci_plat_suspend enlarges its scope, e.g., * also applies to runtime suspend. */ - ret = xhci_suspend(xhci, device_may_wakeup(dev)); - - if (!device_may_wakeup(dev) && !IS_ERR(xhci->clk)) - clk_disable_unprepare(xhci->clk); - - return ret; + return xhci_suspend(xhci, device_may_wakeup(dev)); } static int __maybe_unused xhci_plat_resume(struct device *dev) @@ -379,9 +373,6 @@ static int __maybe_unused xhci_plat_resu struct xhci_hcd *xhci = hcd_to_xhci(hcd); int ret; - if (!device_may_wakeup(dev) && !IS_ERR(xhci->clk)) - clk_prepare_enable(xhci->clk); - ret = xhci_priv_resume_quirk(hcd); if (ret) return ret;