V4L/DVB (12741): em28xx: make video isoc stream work when VBI is enabled

Add code enabling the VBI registers for variants of the em28xx chip that
support VBI, and make sure the isoc streaming code continues to work for
the video component of the stream (note the video and vbi data arrive
intermixed on the same isoc pipe).

Note that this version just drops the actual VBI data onto the floor as
opposed to processing it.  The "#ifdef 0" tags are for the videobuf code that
appears in the next patch in this series.

We created a separate version of the isoc_copy version for parsing the version
of the stream that includes VBI data.  In theory, they might be able to be
merged at some point in the future, but the initial goal is to ensure that we
do not cause any regressions with devices that do not have VBI support.

This work was sponsored by EyeMagnet Limited.

Signed-off-by: Devin Heitmueller <dheitmueller@kernellabs.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 39 insertions, 5 deletions

diff --git a/drivers/media/video/em28xx/em28xx-core.c b/drivers/media/video/em28xx/em28xx-core.c
index 98e140b..d4107f6 100644
--- a/drivers/media/video/em28xx/em28xx-core.c
+++ b/drivers/media/video/em28xx/em28xx-core.c
@@ -54,6 +54,10 @@ static int alt = EM28XX_PINOUT;
 module_param(alt, int, 0644);
 MODULE_PARM_DESC(alt, "alternate setting to use for video endpoint");
 
+static unsigned int disable_vbi;
+module_param(disable_vbi, int, 0644);
+MODULE_PARM_DESC(disable_vbi, "disable vbi support");
+
 /* FIXME */
 #define em28xx_isocdbg(fmt, arg...) do {\
 	if (core_debug) \
@@ -648,9 +652,24 @@ int em28xx_capture_start(struct em28xx *dev, int start)
 	return rc;
 }
 
+int em28xx_vbi_supported(struct em28xx *dev)
+{
+	/* Modprobe option to manually disable */
+	if (disable_vbi == 1)
+		return 0;
+
+	if (dev->chip_id == CHIP_ID_EM2860 ||
+	    dev->chip_id == CHIP_ID_EM2883)
+		return 1;
+
+	/* Version of em28xx that does not support VBI */
+	return 0;
+}
+
 int em28xx_set_outfmt(struct em28xx *dev)
 {
 	int ret;
+	u8 vinctrl;
 
 	ret = em28xx_write_reg_bits(dev, EM28XX_R27_OUTFMT,
 				dev->format->reg | 0x20, 0xff);
@@ -661,7 +680,16 @@ int em28xx_set_outfmt(struct em28xx *dev)
 	if (ret < 0)
 		return ret;
 
-	return em28xx_write_reg(dev, EM28XX_R11_VINCTRL, dev->vinctl);
+	vinctrl = dev->vinctl;
+	if (em28xx_vbi_supported(dev) == 1) {
+		vinctrl |= EM28XX_VINCTRL_VBI_RAW;
+		em28xx_write_reg(dev, EM28XX_R34_VBI_START_H, 0x00);
+		em28xx_write_reg(dev, EM28XX_R35_VBI_START_V, 0x09);
+		em28xx_write_reg(dev, EM28XX_R36_VBI_WIDTH, 0xb4);
+		em28xx_write_reg(dev, EM28XX_R37_VBI_HEIGHT, 0x0c);
+	}
+
+	return em28xx_write_reg(dev, EM28XX_R11_VINCTRL, vinctrl);
 }
 
 static int em28xx_accumulator_set(struct em28xx *dev, u8 xmin, u8 xmax,
@@ -732,7 +760,14 @@ int em28xx_resolution_set(struct em28xx *dev)
 
 
 	em28xx_accumulator_set(dev, 1, (width - 4) >> 2, 1, (height - 4) >> 2);
-	em28xx_capture_area_set(dev, 0, 0, width >> 2, height >> 2);
+
+	/* If we don't set the start position to 4 in VBI mode, we end up
+	   with line 21 being YUYV encoded instead of being in 8-bit
+	   greyscale */
+	if (em28xx_vbi_supported(dev) == 1)
+		em28xx_capture_area_set(dev, 0, 4, width >> 2, height >> 2);
+	else
+		em28xx_capture_area_set(dev, 0, 0, width >> 2, height >> 2);
 
 	return em28xx_scaler_set(dev, dev->hscale, dev->vscale);
 }
@@ -844,8 +879,7 @@ EXPORT_SYMBOL_GPL(em28xx_set_mode);
  */
 static void em28xx_irq_callback(struct urb *urb)
 {
-	struct em28xx_dmaqueue  *dma_q = urb->context;
-	struct em28xx *dev = container_of(dma_q, struct em28xx, vidq);
+	struct em28xx *dev = urb->context;
 	int rc, i;
 
 	switch (urb->status) {
@@ -994,7 +1028,7 @@ int em28xx_init_isoc(struct em28xx *dev, int max_packets,
 
 		usb_fill_int_urb(urb, dev->udev, pipe,
 				 dev->isoc_ctl.transfer_buffer[i], sb_size,
-				 em28xx_irq_callback, dma_q, 1);
+				 em28xx_irq_callback, dev, 1);
 
 		urb->number_of_packets = max_packets;
 		urb->transfer_flags = URB_ISO_ASAP | URB_NO_TRANSFER_DMA_MAP;