V4L/DVB (4909): Add s/g_parm to cafe_ccic

Add s/g_parm support allowing applications to tweak the frame rate.

Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

1 files changed, 67 insertions, 5 deletions

diff --git a/drivers/media/video/ov7670.c b/drivers/media/video/ov7670.c
index 7d380d76338a..89dd18c3c5cc 100644
--- a/drivers/media/video/ov7670.c
+++ b/drivers/media/video/ov7670.c
@@ -36,6 +36,11 @@ MODULE_LICENSE("GPL");
 #define QCIF_HEIGHT     144
 
 /*
+ * Our nominal (default) frame rate.
+ */
+#define OV7670_FRAME_RATE 30
+
+/*
  * The 7670 sits on i2c with ID 0x42
  */
 #define OV7670_I2C_ADDR 0x42
@@ -291,7 +296,7 @@ static struct regval_list ov7670_default_regs[] = {
         { 0xc9, 0x60 },         { REG_COM16, 0x38 },
         { 0x56, 0x40 },
 
-        { 0x34, 0x11 },         { REG_COM11, COM11_EXP },
+        { 0x34, 0x11 },         { REG_COM11, COM11_EXP|COM11_HZAUTO },
         { 0xa4, 0x88 },         { 0x96, 0 },
         { 0x97, 0x30 },         { 0x98, 0x20 },
         { 0x99, 0x30 },         { 0x9a, 0x84 },
@@ -722,6 +727,63 @@ static int ov7670_s_fmt(struct i2c_client *c, struct v4l2_format *fmt)
 }
 
 /*
+ * Implement G/S_PARM.  There is a "high quality" mode we could try
+ * to do someday; for now, we just do the frame rate tweak.
+ */
+static int ov7670_g_parm(struct i2c_client *c, struct v4l2_streamparm *parms)
+{
+        struct v4l2_captureparm *cp = &parms->parm.capture;
+        unsigned char clkrc;
+        int ret;
+
+        if (parms->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
+                return -EINVAL;
+        ret = ov7670_read(c, REG_CLKRC, &clkrc);
+        if (ret < 0)
+                return ret;
+        memset(cp, 0, sizeof(struct v4l2_captureparm));
+        cp->capability = V4L2_CAP_TIMEPERFRAME;
+        cp->timeperframe.numerator = 1;
+        cp->timeperframe.denominator = OV7670_FRAME_RATE;
+        if ((clkrc & CLK_EXT) == 0 && (clkrc & CLK_SCALE) > 1)
+                cp->timeperframe.denominator /= (clkrc & CLK_SCALE);
+        return 0;
+}
+
+static int ov7670_s_parm(struct i2c_client *c, struct v4l2_streamparm *parms)
+{
+        struct v4l2_captureparm *cp = &parms->parm.capture;
+        struct v4l2_fract *tpf = &cp->timeperframe;
+        unsigned char clkrc;
+        int ret, div;
+
+        if (parms->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
+                return -EINVAL;
+        if (cp->extendedmode != 0)
+                return -EINVAL;
+        /*
+         * CLKRC has a reserved bit, so let's preserve it.
+         */
+        ret = ov7670_read(c, REG_CLKRC, &clkrc);
+        if (ret < 0)
+                return ret;
+        if (tpf->numerator == 0 || tpf->denominator == 0)
+                div = 1;  /* Reset to full rate */
+        else
+                div = (tpf->numerator*OV7670_FRAME_RATE)/tpf->denominator;
+        if (div == 0)
+                div = 1;
+        else if (div > CLK_SCALE)
+                div = CLK_SCALE;
+        clkrc = (clkrc & 0x80) | div;
+        tpf->numerator = 1;
+        tpf->denominator = OV7670_FRAME_RATE/div;
+        return ov7670_write(c, REG_CLKRC, clkrc);
+}
+
+
+
+/*
  * Code for dealing with controls.
  */
 
@@ -1231,10 +1293,10 @@ static int ov7670_command(struct i2c_client *client, unsigned int cmd,
                 return ov7670_s_ctrl(client, (struct v4l2_control *) arg);
         case VIDIOC_G_CTRL:
                 return ov7670_g_ctrl(client, (struct v4l2_control *) arg);
-        /* Todo:
-           g/s_parm
-           initialization
-        */
+        case VIDIOC_S_PARM:
+                return ov7670_s_parm(client, (struct v4l2_streamparm *) arg);
+        case VIDIOC_G_PARM:
+                return ov7670_g_parm(client, (struct v4l2_streamparm *) arg);
         }
         return -EINVAL;
 }