Input: synaptics - relax capability ID checks on newer hardware

Older firmwares fixed the middle byte of the Synaptics capabilities
query to 0x47, but starting with firmware 7.5 the middle byte
represents submodel ID, sometimes also called "dash number".

Reported-and-tested-by: Miroslav Šulc <fordfrog@gmail.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

1 files changed, 6 insertions, 1 deletions

diff --git a/drivers/input/mouse/synaptics.c b/drivers/input/mouse/synaptics.c
index 9ba9c4a17e15..705589dc9ac5 100644
--- a/drivers/input/mouse/synaptics.c
+++ b/drivers/input/mouse/synaptics.c
@@ -141,8 +141,13 @@ static int synaptics_capability(struct psmouse *psmouse)
         priv->capabilities = (cap[0] << 16) | (cap[1] << 8) | cap[2];
         priv->ext_cap = priv->ext_cap_0c = 0;
 
-        if (!SYN_CAP_VALID(priv->capabilities))
+        /*
+         * Older firmwares had submodel ID fixed to 0x47
+         */
+        if (SYN_ID_FULL(priv->identity) < 0x705 &&
+            SYN_CAP_SUBMODEL_ID(priv->capabilities) != 0x47) {
                 return -1;
+        }
 
         /*
          * Unless capExtended is set the rest of the flags should be ignored