tty: vt, consw->con_set_palette cleanup

* allow NULL consw->con_set_palette (some consoles define an empty
  hook)
* => remove empty hooks now
* return value of consw->con_set_palette is never checked => make the
  function void
* document consw->con_set_palette a bit

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Thomas Winischhofer <thomas@winischhofer.net>
Cc: linux-usb@vger.kernel.org
Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: linux-fbdev@vger.kernel.org
Cc: linux-parisc@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 4 insertions, 7 deletions

diff --git a/drivers/usb/misc/sisusbvga/sisusb_con.c b/drivers/usb/misc/sisusbvga/sisusb_con.c
index a8244ebeb7a7..4112835f4aed 100644
--- a/drivers/usb/misc/sisusbvga/sisusb_con.c
+++ b/drivers/usb/misc/sisusbvga/sisusb_con.c
@@ -595,7 +595,7 @@ sisusbcon_save_screen(struct vc_data *c)
 }
 
 /* interface routine */
-static int
+static void
 sisusbcon_set_palette(struct vc_data *c, const unsigned char *table)
 {
         struct sisusb_usb_data *sisusb;
@@ -604,17 +604,17 @@ sisusbcon_set_palette(struct vc_data *c, const unsigned char *table)
         /* Return value not used by vt */
 
         if (!CON_IS_VISIBLE(c))
-                return -EINVAL;
+                return;
 
         sisusb = sisusb_get_sisusb_lock_and_check(c->vc_num);
         if (!sisusb)
-                return -EINVAL;
+                return;
 
         /* sisusb->lock is down */
 
         if (sisusb_is_inactive(c, sisusb)) {
                 mutex_unlock(&sisusb->lock);
-                return -EINVAL;
+                return;
         }
 
         for (i = j = 0; i < 16; i++) {
@@ -629,8 +629,6 @@ sisusbcon_set_palette(struct vc_data *c, const unsigned char *table)
         }
 
         mutex_unlock(&sisusb->lock);
-
-        return 0;
 }
 
 /* interface routine */
@@ -1428,7 +1426,6 @@ static const struct consw sisusb_dummy_con = {
         .con_font_get =         SISUSBCONDUMMY,
         .con_font_default =     SISUSBCONDUMMY,
         .con_font_copy =        SISUSBCONDUMMY,
-        .con_set_palette =      SISUSBCONDUMMY,
 };
 
 int