Input: psmouse - clean up Cypress probe

When Cypress protocol support is disabled cypress_init() is a stub that
always returns -ENOSYS, so there is not point in testing for
CONFIG_MOUSE_PS2_CYPRESS after we decided that we are dealing with a
Cypress device. Also, we should only be calling cypress_detect() when
set_properties argument is "true", like with other protocols.

There is a slight change in behavior to make follow-up patches more
uniform: when we detect Cypress but its initialization fails, instead of
immediately returning PSMOUSE_PS2 protocol we now continue trying
IntelliMouse [Explorer]. Given that Cypress devices only have issue with
Sentelic probes probing Imtellimouse should be safe.

Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Tested-by: Marcin Sochacki <msochacki+kernel@gmail.com>
Tested-by: Till <till2.schaefer@uni-dortmund.de>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

1 files changed, 8 insertions, 12 deletions

diff --git a/drivers/input/mouse/psmouse-base.c b/drivers/input/mouse/psmouse-base.c
index c2bd8665e9f2..978ba0bb4bd9 100644
--- a/drivers/input/mouse/psmouse-base.c
+++ b/drivers/input/mouse/psmouse-base.c
@@ -836,19 +836,15 @@ static int psmouse_extensions(struct psmouse *psmouse,
          * Trackpads.
          */
         if (max_proto > PSMOUSE_IMEX &&
-                        cypress_detect(psmouse, set_properties) == 0) {
-                if (IS_ENABLED(CONFIG_MOUSE_PS2_CYPRESS)) {
-                        if (cypress_init(psmouse) == 0)
-                                return PSMOUSE_CYPRESS;
-
-                        /*
-                         * Finger Sensing Pad probe upsets some modules of
-                         * Cypress Trackpad, must avoid Finger Sensing Pad
-                         * probe if Cypress Trackpad device detected.
-                         */
-                        return PSMOUSE_PS2;
-                }
+            psmouse_do_detect(cypress_detect, psmouse, set_properties) == 0) {
+                if (!set_properties || cypress_init(psmouse) == 0)
+                        return PSMOUSE_CYPRESS;
 
+                /*
+                 * Finger Sensing Pad probe upsets some modules of
+                 * Cypress Trackpad, must avoid Finger Sensing Pad
+                 * probe if Cypress Trackpad device detected.
+                 */
                 max_proto = PSMOUSE_IMEX;
         }