[PATCH AUTOSEL 5.4 019/109] USB: EHCI: ehci-mv: improve error handling in mv_ehci_enable()

From: Sasha Levin
Date: Thu Sep 09 2021 - 08:55:16 EST


From: Evgeny Novikov <novikov@xxxxxxxxx>

[ Upstream commit 61136a12cbed234374ec6f588af57c580b20b772 ]

mv_ehci_enable() did not disable and unprepare clocks in case of
failures of phy_init(). Besides, it did not take into account failures
of ehci_clock_enable() (in effect, failures of clk_prepare_enable()).
The patch fixes both issues and gets rid of redundant wrappers around
clk_prepare_enable() and clk_disable_unprepare() to simplify this a bit.

Found by Linux Driver Verification project (linuxtesting.org).

Acked-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Evgeny Novikov <novikov@xxxxxxxxx>
Link: https://lore.kernel.org/r/20210708083056.21543-1-novikov@xxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/usb/host/ehci-mv.c | 23 +++++++++++------------
1 file changed, 11 insertions(+), 12 deletions(-)

diff --git a/drivers/usb/host/ehci-mv.c b/drivers/usb/host/ehci-mv.c
index b6f196f5e252..b0e0f8ea98a9 100644
--- a/drivers/usb/host/ehci-mv.c
+++ b/drivers/usb/host/ehci-mv.c
@@ -41,26 +41,25 @@ struct ehci_hcd_mv {
int (*set_vbus)(unsigned int vbus);
};

-static void ehci_clock_enable(struct ehci_hcd_mv *ehci_mv)
+static int mv_ehci_enable(struct ehci_hcd_mv *ehci_mv)
{
- clk_prepare_enable(ehci_mv->clk);
-}
+ int retval;

-static void ehci_clock_disable(struct ehci_hcd_mv *ehci_mv)
-{
- clk_disable_unprepare(ehci_mv->clk);
-}
+ retval = clk_prepare_enable(ehci_mv->clk);
+ if (retval)
+ return retval;

-static int mv_ehci_enable(struct ehci_hcd_mv *ehci_mv)
-{
- ehci_clock_enable(ehci_mv);
- return phy_init(ehci_mv->phy);
+ retval = phy_init(ehci_mv->phy);
+ if (retval)
+ clk_disable_unprepare(ehci_mv->clk);
+
+ return retval;
}

static void mv_ehci_disable(struct ehci_hcd_mv *ehci_mv)
{
phy_exit(ehci_mv->phy);
- ehci_clock_disable(ehci_mv);
+ clk_disable_unprepare(ehci_mv->clk);
}

static int mv_ehci_reset(struct usb_hcd *hcd)
--
2.30.2