media: ov5670: Fix incorrect frame timing reported to user

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@intel.com>
Reviewed-by: Tomasz Figa <tfiga@chromium.org>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

diff --git a/drivers/media/i2c/ov5670.c b/drivers/media/i2c/ov5670.c
index 8d8e16c5c49f7518ca4a97dbc11b45e532d524d0..b9d4dd278e14203a5f60fd14ff667d32955fbec1 100644 (file)
--- 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 @@ static const char * const ov5670_test_pattern_menu[] = {
 };
 
 /* 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 @@ static const struct ov5670_link_freq_config link_freq_configs[] = {
 };
 
 static const s64 link_freq_menu_items[] = {
-       OV5670_LINK_FREQ_420MHZ
+       OV5670_LINK_FREQ_422MHZ
 };
 
 /*
@@ -1736,7 +1742,7 @@ static const struct ov5670_mode supported_modes[] = {
                        .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 @@ static const struct ov5670_mode supported_modes[] = {
                        .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 @@ static const struct ov5670_mode supported_modes[] = {
                        .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 @@ static const struct ov5670_mode supported_modes[] = {
                        .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 @@ static const struct ov5670_mode supported_modes[] = {
                        .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 @@ static const struct ov5670_mode supported_modes[] = {
                        .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);
        }