1 files changed, 37 insertions, 12 deletions

diff --git a/drivers/media/video/cx18/cx18-driver.c b/drivers/media/video/cx18/cx18-driver.c
index ba4c3ceffbb3..87a735f1ee9e 100644
--- a/drivers/media/video/cx18/cx18-driver.c
+++ b/drivers/media/video/cx18/cx18-driver.c
@@ -211,7 +211,9 @@ MODULE_PARM_DESC(enc_yuv_buffers,
                  "\t\t\tDefault: " __stringify(CX18_DEFAULT_ENC_YUV_BUFFERS));
 MODULE_PARM_DESC(enc_yuv_bufsize,
                  "Size of an encoder YUV buffer (kB)\n"
-                 "\t\t\tDefault: " __stringify(CX18_DEFAULT_ENC_YUV_BUFSIZE));
+                 "\t\t\tAllowed values are multiples of 33.75 kB rounded up\n"
+                 "\t\t\t(multiples of size required for 32 screen lines)\n"
+                 "\t\t\tDefault: 102");
 MODULE_PARM_DESC(enc_yuv_bufs,
                  "Number of encoder YUV buffers\n"
                  "\t\t\tDefault is computed from other enc_yuv_* parameters");
@@ -499,10 +501,27 @@ static void cx18_process_options(struct cx18 *cx)
                         continue;
                 }
                 /*
+                 * YUV is a special case where the stream_buf_size needs to be
+                 * an integral multiple of 33.75 kB (storage for 32 screens
+                 * lines to maintain alignment in case of lost buffers
+                 */
+                if (i == CX18_ENC_STREAM_TYPE_YUV) {
+                        cx->stream_buf_size[i] *= 1024;
+                        cx->stream_buf_size[i] -=
+                           (cx->stream_buf_size[i] % CX18_UNIT_ENC_YUV_BUFSIZE);
+
+                        if (cx->stream_buf_size[i] < CX18_UNIT_ENC_YUV_BUFSIZE)
+                                cx->stream_buf_size[i] =
+                                                CX18_UNIT_ENC_YUV_BUFSIZE;
+                }
+                /*
+                 * YUV is a special case where the stream_buf_size is
+                 * now in bytes.
                  * VBI is a special case where the stream_buf_size is fixed
                  * and already in bytes
                  */
-                if (i == CX18_ENC_STREAM_TYPE_VBI) {
+                if (i == CX18_ENC_STREAM_TYPE_VBI ||
+                    i == CX18_ENC_STREAM_TYPE_YUV) {
                         if (cx->stream_buffers[i] < 0) {
                                 cx->stream_buffers[i] =
                                         cx->options.megabytes[i] * 1024 * 1024
@@ -513,18 +532,24 @@ static void cx18_process_options(struct cx18 *cx)
                                         cx->stream_buffers[i]
                                         * cx->stream_buf_size[i]/(1024 * 1024);
                         }
-                        continue;
-                }
-                /* All other streams have stream_buf_size in kB at this point */
-                if (cx->stream_buffers[i] < 0) {
-                        cx->stream_buffers[i] = cx->options.megabytes[i] * 1024
-                                                / cx->stream_buf_size[i];
                 } else {
-                        /* N.B. This might round down to 0 */
-                        cx->options.megabytes[i] =
-                          cx->stream_buffers[i] * cx->stream_buf_size[i] / 1024;
+                        /* All other streams have stream_buf_size in kB here */
+                        if (cx->stream_buffers[i] < 0) {
+                                cx->stream_buffers[i] =
+                                                cx->options.megabytes[i] * 1024
+                                                / cx->stream_buf_size[i];
+                        } else {
+                                /* N.B. This might round down to 0 */
+                                cx->options.megabytes[i] =
+                                                cx->stream_buffers[i]
+                                                * cx->stream_buf_size[i] / 1024;
+                        }
+                        /* convert from kB to bytes */
+                        cx->stream_buf_size[i] *= 1024;
                 }
-                cx->stream_buf_size[i] *= 1024; /* convert from kB to bytes */
+                CX18_DEBUG_INFO("Stream type %d options: %d MB, %d buffers, "
+                                "%d bytes\n", i, cx->options.megabytes[i],
+                                cx->stream_buffers[i], cx->stream_buf_size[i]);
         }
 
         cx->options.cardtype = cardtype[cx->instance];