From d56e57ca030c8b4296944a2ae61ac167bf979c07 Mon Sep 17 00:00:00 2001
From: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Date: Thu, 8 Mar 2018 17:17:16 +0200
Subject: [PATCH] usb: host: xhci-plat: revert "usb: host: xhci-plat: enable clk in resume timing"
Git-commit: d56e57ca030c8b4296944a2ae61ac167bf979c07
Patch-mainline: v4.16-rc6
References: bsc#1051510
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 <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/usb/host/xhci-plat.c | 11 +----------
1 file changed, 1 insertion(+), 10 deletions(-)
diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
index 6f038306c14d..6652e2d5bd2e 100644
--- a/drivers/usb/host/xhci-plat.c
+++ b/drivers/usb/host/xhci-plat.c
@@ -360,7 +360,6 @@ static int __maybe_unused xhci_plat_suspend(struct device *dev)
{
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
@@ -370,12 +369,7 @@ static int __maybe_unused xhci_plat_suspend(struct device *dev)
* 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)
@@ -384,9 +378,6 @@ static int __maybe_unused xhci_plat_resume(struct device *dev)
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;
--
2.18.0