[media] media: rcar-vin: add support for V4L2_FIELD_ALTERNATE

The HW can capture both ODD and EVEN fields in separate buffers so it's
possible to support V4L2_FIELD_ALTERNATE. This patch add support for
this mode.

At probe time and when S_STD is called the driver will default to use
V4L2_FIELD_INTERLACED if the subdevice reports V4L2_FIELD_ALTERNATE. The
driver will only change the field type if the subdevice implements
G_STD, if not it will keep the default at V4L2_FIELD_ALTERNATE.

The user can always explicitly ask for V4L2_FIELD_ALTERNATE in S_FMT and
the driver will use that field format.

Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

diff --git a/drivers/media/platform/rcar-vin/rcar-dma.c b/drivers/media/platform/rcar-vin/rcar-dma.c
index 01182e0a86f8bc16c31db0c5ddd7e0bb8d440e2f..9ccd5ff55e19251440038b514e258265af282212 100644 (file)
--- a/drivers/media/platform/rcar-vin/rcar-dma.c
+++ b/drivers/media/platform/rcar-vin/rcar-dma.c
@@ -95,6 +95,7 @@
 /* Video n Module Status Register bits */
 #define VNMS_FBS_MASK          (3 << 3)
 #define VNMS_FBS_SHIFT         3
+#define VNMS_FS                        (1 << 2)
 #define VNMS_AV                        (1 << 1)
 #define VNMS_CA                        (1 << 0)
 
@@ -156,6 +157,7 @@ static int rvin_setup(struct rvin_dev *vin)
        case V4L2_FIELD_INTERLACED_BT:
                vnmc = VNMC_IM_FULL | VNMC_FOC;
                break;
+       case V4L2_FIELD_ALTERNATE:
        case V4L2_FIELD_NONE:
                if (vin->continuous) {
                        vnmc = VNMC_IM_ODD_EVEN;
@@ -329,15 +331,26 @@ static bool rvin_capture_active(struct rvin_dev *vin)
        return rvin_read(vin, VNMS_REG) & VNMS_CA;
 }
 
-static int rvin_get_active_slot(struct rvin_dev *vin)
+static int rvin_get_active_slot(struct rvin_dev *vin, u32 vnms)
 {
        if (vin->continuous)
-               return (rvin_read(vin, VNMS_REG) & VNMS_FBS_MASK)
-                       >> VNMS_FBS_SHIFT;
+               return (vnms & VNMS_FBS_MASK) >> VNMS_FBS_SHIFT;
 
        return 0;
 }
 
+static enum v4l2_field rvin_get_active_field(struct rvin_dev *vin, u32 vnms)
+{
+       if (vin->format.field == V4L2_FIELD_ALTERNATE) {
+               /* If FS is set it's a Even field */
+               if (vnms & VNMS_FS)
+                       return V4L2_FIELD_BOTTOM;
+               return V4L2_FIELD_TOP;
+       }
+
+       return vin->format.field;
+}
+
 static void rvin_set_slot_addr(struct rvin_dev *vin, int slot, dma_addr_t addr)
 {
        const struct rvin_video_format *fmt;
@@ -878,7 +891,7 @@ static bool rvin_fill_hw(struct rvin_dev *vin)
 static irqreturn_t rvin_irq(int irq, void *data)
 {
        struct rvin_dev *vin = data;
-       u32 int_status;
+       u32 int_status, vnms;
        int slot;
        unsigned int sequence, handled = 0;
        unsigned long flags;
@@ -905,7 +918,8 @@ static irqreturn_t rvin_irq(int irq, void *data)
        }
 
        /* Prepare for capture and update state */
-       slot = rvin_get_active_slot(vin);
+       vnms = rvin_read(vin, VNMS_REG);
+       slot = rvin_get_active_slot(vin, vnms);
        sequence = vin->sequence++;
 
        vin_dbg(vin, "IRQ %02d: %d\tbuf0: %c buf1: %c buf2: %c\tmore: %d\n",
@@ -920,7 +934,7 @@ static irqreturn_t rvin_irq(int irq, void *data)
                goto done;
 
        /* Capture frame */
-       vin->queue_buf[slot]->field = vin->format.field;
+       vin->queue_buf[slot]->field = rvin_get_active_field(vin, vnms);
        vin->queue_buf[slot]->sequence = sequence;
        vin->queue_buf[slot]->vb2_buf.timestamp = ktime_get_ns();
        vb2_buffer_done(&vin->queue_buf[slot]->vb2_buf, VB2_BUF_STATE_DONE);

diff --git a/drivers/media/platform/rcar-vin/rcar-v4l2.c b/drivers/media/platform/rcar-vin/rcar-v4l2.c
index 1392514d4072f3db75f16a447e280e50297ee379..61e9b59dcf44eb876cf606b81c4b7f3352aad1f0 100644 (file)
--- a/drivers/media/platform/rcar-vin/rcar-v4l2.c
+++ b/drivers/media/platform/rcar-vin/rcar-v4l2.c
@@ -122,9 +122,21 @@ static int rvin_reset_format(struct rvin_dev *vin)
        vin->format.colorspace  = mf->colorspace;
        vin->format.field       = mf->field;
 
+       /*
+        * If the subdevice uses ALTERNATE field mode and G_STD is
+        * implemented use the VIN HW to combine the two fields to
+        * one INTERLACED frame. The ALTERNATE field mode can still
+        * be requested in S_FMT and be respected, this is just the
+        * default which is applied at probing or when S_STD is called.
+        */
+       if (vin->format.field == V4L2_FIELD_ALTERNATE &&
+           v4l2_subdev_has_op(vin_to_source(vin), video, g_std))
+               vin->format.field = V4L2_FIELD_INTERLACED;
+
        switch (vin->format.field) {
        case V4L2_FIELD_TOP:
        case V4L2_FIELD_BOTTOM:
+       case V4L2_FIELD_ALTERNATE:
                vin->format.height /= 2;
                break;
        case V4L2_FIELD_NONE:
@@ -225,6 +237,7 @@ static int __rvin_try_format(struct rvin_dev *vin,
        switch (pix->field) {
        case V4L2_FIELD_TOP:
        case V4L2_FIELD_BOTTOM:
+       case V4L2_FIELD_ALTERNATE:
                pix->height /= 2;
                source->height /= 2;
                break;