usb: host: xhci-plat: revert "usb: host: xhci-plat: enable clk in resume timing"

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>

diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
index 6f03830..6652e2d 100644 (file)
--- 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;