usb: chipidea: fix no transceiver case

Since usb phy code does return ERR_PTR() values, make sure that we don't
end up dereferencing them. This is a problem, for example, on platforms
that don't register a phy for chipidea since b7fa5c2a ("usb: phy: return
-ENXIO when PHY layer isn't enabled").

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 8 insertions, 5 deletions

diff --git a/drivers/usb/chipidea/udc.c b/drivers/usb/chipidea/udc.c
index 519ead2443c5..b501346484ae 100644
--- a/drivers/usb/chipidea/udc.c
+++ b/drivers/usb/chipidea/udc.c
@@ -1678,8 +1678,11 @@ static int udc_start(struct ci13xxx *ci)
 
         ci->gadget.ep0 = &ci->ep0in->ep;
 
-        if (ci->global_phy)
+        if (ci->global_phy) {
                 ci->transceiver = usb_get_phy(USB_PHY_TYPE_USB2);
+                if (IS_ERR(ci->transceiver))
+                        ci->transceiver = NULL;
+        }
 
         if (ci->platdata->flags & CI13XXX_REQUIRE_TRANSCEIVER) {
                 if (ci->transceiver == NULL) {
@@ -1694,7 +1697,7 @@ static int udc_start(struct ci13xxx *ci)
                         goto put_transceiver;
         }
 
-        if (!IS_ERR_OR_NULL(ci->transceiver)) {
+        if (ci->transceiver) {
                 retval = otg_set_peripheral(ci->transceiver->otg,
                                                 &ci->gadget);
                 if (retval)
@@ -1711,7 +1714,7 @@ static int udc_start(struct ci13xxx *ci)
         return retval;
 
 remove_trans:
-        if (!IS_ERR_OR_NULL(ci->transceiver)) {
+        if (ci->transceiver) {
                 otg_set_peripheral(ci->transceiver->otg, NULL);
                 if (ci->global_phy)
                         usb_put_phy(ci->transceiver);
@@ -1719,7 +1722,7 @@ remove_trans:
 
         dev_err(dev, "error = %i\n", retval);
 put_transceiver:
-        if (!IS_ERR_OR_NULL(ci->transceiver) && ci->global_phy)
+        if (ci->transceiver && ci->global_phy)
                 usb_put_phy(ci->transceiver);
 destroy_eps:
         destroy_eps(ci);
@@ -1747,7 +1750,7 @@ static void udc_stop(struct ci13xxx *ci)
         dma_pool_destroy(ci->td_pool);
         dma_pool_destroy(ci->qh_pool);
 
-        if (!IS_ERR_OR_NULL(ci->transceiver)) {
+        if (ci->transceiver) {
                 otg_set_peripheral(ci->transceiver->otg, NULL);
                 if (ci->global_phy)
                         usb_put_phy(ci->transceiver);