Previously, pixel-rate/(pixels-per-line * lines-per-frame) was
yielding incorrect frame timing for the user.
OV sensor is using internal timing and this requires
conversion (internal timing -> PPL) for correct HBLANK calculation.
Now, change pixels-per-line domain from internal sensor clock to
pixels domain. Set HBLANK read-only because fixed PPL is used for all
resolutions. And, use more accurate link-frequency 422.4MHz instead of
rounding down to 420MHz.
Signed-off-by: Chiranjeevi Rapolu <chiranjeevi.rapolu@xxxxxxxxx>
---
Changes in v2:
- Change subject to reflect frame timing info.
- Change OV5670_DEF_PPL so that it doesn't convey a register default
value. And, add more comments to it.
drivers/media/i2c/ov5670.c | 45 +++++++++++++++++++++++----------------------
1 file changed, 23 insertions(+), 22 deletions(-)
diff --git a/drivers/media/i2c/ov5670.c b/drivers/media/i2c/ov5670.c
index 8d8e16c..b9d4dd2 100644
--- a/drivers/media/i2c/ov5670.c
+++ b/drivers/media/i2c/ov5670.c
@@ -37,7 +37,13 @@
/* horizontal-timings from sensor */
#define OV5670_REG_HTS 0x380c
-#define OV5670_DEF_PPL 3360 /* Default pixels per line */
+
+/*
+ * Pixels-per-line(PPL) = Time-per-line * pixel-rate
+ * In OV5670, Time-per-line = HTS/SCLK.
+ * HTS is fixed for all resolutions, not recommended to change.
+ */
+#define OV5670_FIXED_PPL 2724 /* Pixels per line */
/* Exposure controls from sensor */
#define OV5670_REG_EXPOSURE 0x3500
@@ -1705,12 +1711,12 @@ struct ov5670_mode {
};
/* Supported link frequencies */
-#define OV5670_LINK_FREQ_420MHZ 420000000
-#define OV5670_LINK_FREQ_420MHZ_INDEX 0
+#define OV5670_LINK_FREQ_422MHZ 422400000
+#define OV5670_LINK_FREQ_422MHZ_INDEX 0
static const struct ov5670_link_freq_config link_freq_configs[] = {
{
/* pixel_rate = link_freq * 2 * nr_of_lanes / bits_per_sample */
- .pixel_rate = (OV5670_LINK_FREQ_420MHZ * 2 * 2) / 10,
+ .pixel_rate = (OV5670_LINK_FREQ_422MHZ * 2 * 2) / 10,
.reg_list = {
.num_of_regs = ARRAY_SIZE(mipi_data_rate_840mbps),
.regs = mipi_data_rate_840mbps,
@@ -1719,7 +1725,7 @@ struct ov5670_mode {
};
static const s64 link_freq_menu_items[] = {
- OV5670_LINK_FREQ_420MHZ
+ OV5670_LINK_FREQ_422MHZ
};
/*
@@ -1736,7 +1742,7 @@ struct ov5670_mode {
.num_of_regs = ARRAY_SIZE(mode_2592x1944_regs),
.regs = mode_2592x1944_regs,
},
- .link_freq_index = OV5670_LINK_FREQ_420MHZ_INDEX,
+ .link_freq_index = OV5670_LINK_FREQ_422MHZ_INDEX,
},
{
.width = 1296,
@@ -1746,7 +1752,7 @@ struct ov5670_mode {
.num_of_regs = ARRAY_SIZE(mode_1296x972_regs),
.regs = mode_1296x972_regs,
},
- .link_freq_index = OV5670_LINK_FREQ_420MHZ_INDEX,
+ .link_freq_index = OV5670_LINK_FREQ_422MHZ_INDEX,
},
{
.width = 648,
@@ -1756,7 +1762,7 @@ struct ov5670_mode {
.num_of_regs = ARRAY_SIZE(mode_648x486_regs),
.regs = mode_648x486_regs,
},
- .link_freq_index = OV5670_LINK_FREQ_420MHZ_INDEX,
+ .link_freq_index = OV5670_LINK_FREQ_422MHZ_INDEX,
},
{
.width = 2560,
@@ -1766,7 +1772,7 @@ struct ov5670_mode {
.num_of_regs = ARRAY_SIZE(mode_2560x1440_regs),
.regs = mode_2560x1440_regs,
},
- .link_freq_index = OV5670_LINK_FREQ_420MHZ_INDEX,
+ .link_freq_index = OV5670_LINK_FREQ_422MHZ_INDEX,
},
{
.width = 1280,
@@ -1776,7 +1782,7 @@ struct ov5670_mode {
.num_of_regs = ARRAY_SIZE(mode_1280x720_regs),
.regs = mode_1280x720_regs,
},
- .link_freq_index = OV5670_LINK_FREQ_420MHZ_INDEX,
+ .link_freq_index = OV5670_LINK_FREQ_422MHZ_INDEX,
},
{
.width = 640,
@@ -1786,7 +1792,7 @@ struct ov5670_mode {
.num_of_regs = ARRAY_SIZE(mode_640x360_regs),
.regs = mode_640x360_regs,
},
- .link_freq_index = OV5670_LINK_FREQ_420MHZ_INDEX,
+ .link_freq_index = OV5670_LINK_FREQ_422MHZ_INDEX,
}
};
@@ -2016,13 +2022,6 @@ static int ov5670_set_ctrl(struct v4l2_ctrl *ctrl)
OV5670_REG_VALUE_16BIT,
ov5670->cur_mode->height + ctrl->val);
break;
- case V4L2_CID_HBLANK:
- /* Update HTS that meets expected horizontal blanking */
- ret = ov5670_write_reg(ov5670, OV5670_REG_HTS,
- OV5670_REG_VALUE_16BIT,
- (ov5670->cur_mode->width +
- ctrl->val) / 2);
- break;
case V4L2_CID_TEST_PATTERN:
ret = ov5670_enable_test_pattern(ov5670, ctrl->val);
break;
@@ -2078,9 +2077,11 @@ static int ov5670_init_controls(struct ov5670 *ov5670)
ov5670->hblank = v4l2_ctrl_new_std(
ctrl_hdlr, &ov5670_ctrl_ops, V4L2_CID_HBLANK,
- OV5670_DEF_PPL - ov5670->cur_mode->width,
- OV5670_DEF_PPL - ov5670->cur_mode->width, 1,
- OV5670_DEF_PPL - ov5670->cur_mode->width);
+ OV5670_FIXED_PPL - ov5670->cur_mode->width,
+ OV5670_FIXED_PPL - ov5670->cur_mode->width, 1,
+ OV5670_FIXED_PPL - ov5670->cur_mode->width);
+ if (ov5670->hblank)
+ ov5670->hblank->flags |= V4L2_CTRL_FLAG_READ_ONLY;
/* Get min, max, step, default from sensor */
v4l2_ctrl_new_std(ctrl_hdlr, &ov5670_ctrl_ops, V4L2_CID_ANALOGUE_GAIN,
@@ -2247,7 +2248,7 @@ static int ov5670_set_pad_format(struct v4l2_subdev *sd,
OV5670_VTS_MAX - ov5670->cur_mode->height, 1,
vblank_def);
__v4l2_ctrl_s_ctrl(ov5670->vblank, vblank_def);
- h_blank = OV5670_DEF_PPL - ov5670->cur_mode->width;
+ h_blank = OV5670_FIXED_PPL - ov5670->cur_mode->width;
__v4l2_ctrl_modify_range(ov5670->hblank, h_blank, h_blank, 1,
h_blank);
}
--
1.9.1
