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

In the pvrusb2 driver, different interfaces (e.g. V4L, DVB) have

Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

1 files changed, 69 insertions, 0 deletions

diff --git a/drivers/media/video/pvrusb2/pvrusb2-context.c b/drivers/media/video/pvrusb2/pvrusb2-context.c
index a2ce022c515a..b5db6a5bab31 100644
--- 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)
 {