usb: gadget: f_mass_storage: Disable eps during disconnect

When receiving a disconnect event from the UDC, the mass storage
function driver currently runs the handle_exception() routine
asynchronously.  For UDCs that support runtime PM, there is a
possibility the UDC is already suspended by the time the
do_set_interface() is executed.  This can lead to HW register access
while the UDC is already suspended.

Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Wesley Cheng <quic_wcheng@quicinc.com>
Link: https://lore.kernel.org/r/1635365407-31337-3-git-send-email-quic_wcheng@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/gadget/function/f_mass_storage.c b/drivers/usb/gadget/function/f_mass_storage.c
index 3cabf76..7524396 100644 (file)
--- a/drivers/usb/gadget/function/f_mass_storage.c
+++ b/drivers/usb/gadget/function/f_mass_storage.c
@@ -2342,6 +2342,16 @@ static void fsg_disable(struct usb_function *f)
 {
        struct fsg_dev *fsg = fsg_from_func(f);
 
+       /* Disable the endpoints */
+       if (fsg->bulk_in_enabled) {
+               usb_ep_disable(fsg->bulk_in);
+               fsg->bulk_in_enabled = 0;
+       }
+       if (fsg->bulk_out_enabled) {
+               usb_ep_disable(fsg->bulk_out);
+               fsg->bulk_out_enabled = 0;
+       }
+
        __raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE, NULL);
 }