media: tvp5150: disable output while signal not locked

To avoid short frames on stream start, keep output pins at high impedance
while we are not properly locked onto the input signal.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

diff --git a/drivers/media/i2c/tvp5150.c b/drivers/media/i2c/tvp5150.c
index b66fc4e3ecbbb4efb0342b431db0749e7025366a..0b8cd58bf1f1765201792c0a8832b5797d2a53b0 100644 (file)
--- a/drivers/media/i2c/tvp5150.c
+++ b/drivers/media/i2c/tvp5150.c
@@ -65,6 +65,7 @@ struct tvp5150 {
        v4l2_std_id detected_norm;
        u32 input;
        u32 output;
+       u32 oe;
        int enable;
        bool lock;
 
@@ -804,14 +805,20 @@ static irqreturn_t tvp5150_isr(int irq, void *dev_id)
 {
        struct tvp5150 *decoder = dev_id;
        struct regmap *map = decoder->regmap;
-       unsigned int active = 0, status = 0;
+       unsigned int mask, active = 0, status = 0;
+
+       mask = TVP5150_MISC_CTL_YCBCR_OE | TVP5150_MISC_CTL_SYNC_OE |
+              TVP5150_MISC_CTL_CLOCK_OE;
 
        regmap_read(map, TVP5150_INT_STATUS_REG_A, &status);
        if (status) {
                regmap_write(map, TVP5150_INT_STATUS_REG_A, status);
 
-               if (status & TVP5150_INT_A_LOCK)
+               if (status & TVP5150_INT_A_LOCK) {
                        decoder->lock = !!(status & TVP5150_INT_A_LOCK_STATUS);
+                       regmap_update_bits(map, TVP5150_MISC_CTL, mask,
+                                          decoder->lock ? decoder->oe : 0);
+               }
 
                return IRQ_HANDLED;
        }
@@ -877,10 +884,26 @@ static int tvp5150_enable(struct v4l2_subdev *sd)
        /* Disable autoswitch mode */
        tvp5150_set_std(sd, std);
 
-       if (decoder->mbus_type == V4L2_MBUS_PARALLEL)
+       /*
+        * Enable the YCbCr and clock outputs. In discrete sync mode
+        * (non-BT.656) additionally enable the the sync outputs.
+        */
+       switch (decoder->mbus_type) {
+       case V4L2_MBUS_PARALLEL:
                /* 8-bit 4:2:2 YUV with discrete sync output */
                regmap_update_bits(decoder->regmap, TVP5150_DATA_RATE_SEL,
                                   0x7, 0x0);
+               decoder->oe = TVP5150_MISC_CTL_YCBCR_OE |
+                             TVP5150_MISC_CTL_CLOCK_OE |
+                             TVP5150_MISC_CTL_SYNC_OE;
+               break;
+       case V4L2_MBUS_BT656:
+               decoder->oe = TVP5150_MISC_CTL_YCBCR_OE |
+                             TVP5150_MISC_CTL_CLOCK_OE;
+               break;
+       default:
+               return -EINVAL;
+       }
 
        return 0;
 };
@@ -1157,14 +1180,8 @@ static int tvp5150_s_stream(struct v4l2_subdev *sd, int enable)
        if (enable) {
                tvp5150_enable(sd);
 
-               /*
-                * Enable the YCbCr and clock outputs. In discrete sync mode
-                * (non-BT.656) additionally enable the the sync outputs.
-                */
-               val = TVP5150_MISC_CTL_YCBCR_OE | TVP5150_MISC_CTL_CLOCK_OE;
-               if (decoder->mbus_type == V4L2_MBUS_PARALLEL)
-                       val |= TVP5150_MISC_CTL_SYNC_OE;
-
+               /* Enable outputs if decoder is locked */
+               val = decoder->lock ? decoder->oe : 0;
                int_val = TVP5150_INT_A_LOCK;
        }