V4L/DVB (9802): cx18: Add module parameters for finer control over buffer allocations

cx18: Add module parameters for finer control over buffer allocations.
User now has the option of setting smaller buffers to get lower
latency transfers from the encoder.  User can also now set the number
of buffers used for a stream explicitly.

Signed-off-by: Andy Walls <awalls@radix.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/drivers/media/video/cx18/cx18-driver.h b/drivers/media/video/cx18/cx18-driver.h
index 4d56d07195b6..29c296f39f91 100644
--- a/drivers/media/video/cx18/cx18-driver.h
+++ b/drivers/media/video/cx18/cx18-driver.h
@@ -115,6 +115,17 @@
 #define CX18_DEFAULT_ENC_VBI_BUFFERS 1
 #define CX18_DEFAULT_ENC_PCM_BUFFERS 1
 
+/* Maximum firmware DMA buffers per stream */
+#define CX18_MAX_MDLS_PER_STREAM 63
+
+/* DMA buffer, default size in kB allocated */
+#define CX18_DEFAULT_ENC_TS_BUFSIZE   32
+#define CX18_DEFAULT_ENC_MPG_BUFSIZE  32
+#define CX18_DEFAULT_ENC_IDX_BUFSIZE  32
+#define CX18_DEFAULT_ENC_YUV_BUFSIZE 128
+/* Default VBI bufsize based on standards supported by card tuner for now */
+#define CX18_DEFAULT_ENC_PCM_BUFSIZE   4
+
 /* i2c stuff */
 #define I2C_CLIENTS_MAX 16
 
@@ -408,6 +419,7 @@ struct cx18 {
 
         struct mutex serialize_lock;    /* mutex used to serialize open/close/start/stop/ioctl operations */
         struct cx18_options options;    /* User options */
+        int stream_buffers[CX18_MAX_STREAMS]; /* # of buffers for each stream */
         int stream_buf_size[CX18_MAX_STREAMS]; /* Stream buffer size */
         struct cx18_stream streams[CX18_MAX_STREAMS];   /* Stream data */
         unsigned long i_flags;  /* global cx18 flags */