V4L/DVB (7719): pvrusb2: Implement input selection enforcement

[safe/jmp/linux-2.6] / drivers / media / video / pvrusb2 / pvrusb2-context.c

diff --git a/drivers/media/video/pvrusb2/pvrusb2-context.c b/drivers/media/video/pvrusb2/pvrusb2-context.c
index a2ce022..b5db6a5 100644 (file)
--- a/drivers/media/video/pvrusb2/pvrusb2-context.c
+++ b/drivers/media/video/pvrusb2/pvrusb2-context.c
@@ -245,6 +245,22 @@ struct pvr2_context *pvr2_context_create(
 }
 
 
+static void pvr2_context_reset_input_limits(struct pvr2_context *mp)
+{
+       unsigned int tmsk,mmsk;
+       struct pvr2_channel *cp;
+       struct pvr2_hdw *hdw = mp->hdw;
+       mmsk = pvr2_hdw_get_input_available(hdw);
+       tmsk = mmsk;
+       for (cp = mp->mc_first; cp; cp = cp->mc_next) {
+               if (!cp->input_mask) continue;
+               tmsk &= cp->input_mask;
+       }
+       pvr2_hdw_set_input_allowed(hdw,mmsk,tmsk);
+       pvr2_hdw_commit_ctl(hdw);
+}
+
+
 static void pvr2_context_enter(struct pvr2_context *mp)
 {
        mutex_lock(&mp->mutex);
@@ -300,7 +316,9 @@ void pvr2_channel_done(struct pvr2_channel *cp)
 {
        struct pvr2_context *mp = cp->mc_head;
        pvr2_context_enter(mp);
+       cp->input_mask = 0;
        pvr2_channel_disclaim_stream(cp);
+       pvr2_context_reset_input_limits(mp);
        if (cp->mc_next) {
                cp->mc_next->mc_prev = cp->mc_prev;
        } else {
@@ -316,6 +334,57 @@ void pvr2_channel_done(struct pvr2_channel *cp)
 }
 
 
+int pvr2_channel_limit_inputs(struct pvr2_channel *cp,unsigned int cmsk)
+{
+       unsigned int tmsk,mmsk;
+       int ret = 0;
+       struct pvr2_channel *p2;
+       struct pvr2_hdw *hdw = cp->hdw;
+
+       mmsk = pvr2_hdw_get_input_available(hdw);
+       cmsk &= mmsk;
+       if (cmsk == cp->input_mask) {
+               /* No change; nothing to do */
+               return 0;
+       }
+
+       pvr2_context_enter(cp->mc_head);
+       do {
+               if (!cmsk) {
+                       cp->input_mask = 0;
+                       pvr2_context_reset_input_limits(cp->mc_head);
+                       break;
+               }
+               tmsk = mmsk;
+               for (p2 = cp->mc_head->mc_first; p2; p2 = p2->mc_next) {
+                       if (p2 == cp) continue;
+                       if (!p2->input_mask) continue;
+                       tmsk &= p2->input_mask;
+               }
+               if (!(tmsk & cmsk)) {
+                       ret = -EPERM;
+                       break;
+               }
+               tmsk &= cmsk;
+               if ((ret = pvr2_hdw_set_input_allowed(hdw,mmsk,tmsk)) != 0) {
+                       /* Internal failure changing allowed list; probably
+                          should not happen, but react if it does. */
+                       break;
+               }
+               cp->input_mask = cmsk;
+               pvr2_hdw_commit_ctl(hdw);
+       } while (0);
+       pvr2_context_exit(cp->mc_head);
+       return ret;
+}
+
+
+unsigned int pvr2_channel_get_limited_inputs(struct pvr2_channel *cp)
+{
+       return cp->input_mask;
+}
+
+
 int pvr2_channel_claim_stream(struct pvr2_channel *cp,
                              struct pvr2_context_stream *sp)
 {