media: i2c: ov5647: Support HFLIP and VFLIP

Add missing controls for horizontal and vertical flipping.

The sensor readout mirrors in the horizontal direction by default (if
0x3821[1] = 0) which can make things unnecessarily difficult for
applications. The register table prior to this commit was setting that
bit explicitly, to achieve a normally oriented image.

Now that we have userspace controls for HFLIP, we keep the convention
and report the non-mirrored image (with 0x3821[1] = 1) as
horizontal_flip=0, and vice versa.

Signed-off-by: David Plowman <david.plowman@raspberrypi.com>
Reviewed-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
Co-developed-by: Jai Luthra <jai.luthra@ideasonboard.com>
Signed-off-by: Jai Luthra <jai.luthra@ideasonboard.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>

diff --git a/drivers/media/i2c/ov5647.c b/drivers/media/i2c/ov5647.c
index 6f07cac12c6c157e1b20abe000f95de82abd877a..5bb80b943c8b5b922bd74e3c185c5e88f4f1a671 100644 (file)
--- a/drivers/media/i2c/ov5647.c
+++ b/drivers/media/i2c/ov5647.c
@@ -55,6 +55,8 @@
 #define OV5647_REG_GAIN_LO             0x350b
 #define OV5647_REG_VTS_HI              0x380e
 #define OV5647_REG_VTS_LO              0x380f
+#define OV5647_REG_TIMING_TC_V         0x3820
+#define OV5647_REG_TIMING_TC_H         0x3821
 #define OV5647_REG_FRAME_OFF_NUMBER    0x4202
 #define OV5647_REG_MIPI_CTRL00         0x4800
 #define OV5647_REG_MIPI_CTRL14         0x4814
@@ -120,6 +122,8 @@ struct ov5647 {
        struct v4l2_ctrl                *hblank;
        struct v4l2_ctrl                *vblank;
        struct v4l2_ctrl                *exposure;
+       struct v4l2_ctrl                *hflip;
+       struct v4l2_ctrl                *vflip;
 };
 
 static inline struct ov5647 *to_sensor(struct v4l2_subdev *sd)
@@ -161,7 +165,7 @@ static struct regval_list ov5647_2592x1944_10bpp[] = {
        {0x3036, 0x69},
        {0x303c, 0x11},
        {0x3106, 0xf5},
-       {0x3821, 0x06},
+       {0x3821, 0x02},
        {0x3820, 0x00},
        {0x3827, 0xec},
        {0x370c, 0x03},
@@ -250,7 +254,7 @@ static struct regval_list ov5647_1080p30_10bpp[] = {
        {0x3036, 0x62},
        {0x303c, 0x11},
        {0x3106, 0xf5},
-       {0x3821, 0x06},
+       {0x3821, 0x02},
        {0x3820, 0x00},
        {0x3827, 0xec},
        {0x370c, 0x03},
@@ -414,7 +418,7 @@ static struct regval_list ov5647_2x2binned_10bpp[] = {
        {0x4800, 0x24},
        {0x3503, 0x03},
        {0x3820, 0x41},
-       {0x3821, 0x07},
+       {0x3821, 0x03},
        {0x350a, 0x00},
        {0x350b, 0x10},
        {0x3500, 0x00},
@@ -430,7 +434,7 @@ static struct regval_list ov5647_640x480_10bpp[] = {
        {0x3035, 0x11},
        {0x3036, 0x46},
        {0x303c, 0x11},
-       {0x3821, 0x07},
+       {0x3821, 0x03},
        {0x3820, 0x41},
        {0x370c, 0x03},
        {0x3612, 0x59},
@@ -956,6 +960,26 @@ static const struct v4l2_subdev_video_ops ov5647_subdev_video_ops = {
        .s_stream =             ov5647_s_stream,
 };
 
+/*
+ * This function returns the mbus code for the current settings of the HFLIP
+ * and VFLIP controls.
+ */
+static u32 ov5647_get_mbus_code(struct v4l2_subdev *sd)
+{
+       struct ov5647 *sensor = to_sensor(sd);
+       /* The control values are only 0 or 1. */
+       int index =  sensor->hflip->val | (sensor->vflip->val << 1);
+
+       static const u32 codes[4] = {
+               MEDIA_BUS_FMT_SGBRG10_1X10,
+               MEDIA_BUS_FMT_SBGGR10_1X10,
+               MEDIA_BUS_FMT_SRGGB10_1X10,
+               MEDIA_BUS_FMT_SGRBG10_1X10
+       };
+
+       return codes[index];
+}
+
 static int ov5647_enum_mbus_code(struct v4l2_subdev *sd,
                                 struct v4l2_subdev_state *sd_state,
                                 struct v4l2_subdev_mbus_code_enum *code)
@@ -963,7 +987,7 @@ static int ov5647_enum_mbus_code(struct v4l2_subdev *sd,
        if (code->index > 0)
                return -EINVAL;
 
-       code->code = MEDIA_BUS_FMT_SBGGR10_1X10;
+       code->code = ov5647_get_mbus_code(sd);
 
        return 0;
 }
@@ -974,7 +998,7 @@ static int ov5647_enum_frame_size(struct v4l2_subdev *sd,
 {
        const struct v4l2_mbus_framefmt *fmt;
 
-       if (fse->code != MEDIA_BUS_FMT_SBGGR10_1X10 ||
+       if (fse->code != ov5647_get_mbus_code(sd) ||
            fse->index >= ARRAY_SIZE(ov5647_modes))
                return -EINVAL;
 
@@ -1007,6 +1031,8 @@ static int ov5647_get_pad_fmt(struct v4l2_subdev *sd,
        }
 
        *fmt = *sensor_format;
+       /* The code we pass back must reflect the current h/vflips. */
+       fmt->code = ov5647_get_mbus_code(sd);
        mutex_unlock(&sensor->lock);
 
        return 0;
@@ -1054,6 +1080,8 @@ static int ov5647_set_pad_fmt(struct v4l2_subdev *sd,
                                         exposure_def);
        }
        *fmt = mode->format;
+       /* The code we pass back must reflect the current h/vflips. */
+       fmt->code = ov5647_get_mbus_code(sd);
        mutex_unlock(&sensor->lock);
 
        return 0;
@@ -1229,6 +1257,31 @@ static int ov5647_s_exposure(struct v4l2_subdev *sd, u32 val)
        return ov5647_write(sd, OV5647_REG_EXP_LO, (val & 0xf) << 4);
 }
 
+static int ov5647_s_flip(struct v4l2_subdev *sd, u16 reg, u32 ctrl_val)
+{
+       u8 reg_val;
+       int ret;
+
+       /*
+        * TIMING TC REG20 (Vertical) and REG21 (Horizontal):
+        * - [2]:       ISP mirror/flip
+        * - [1]:       Sensor mirror/flip
+        *
+        * We only use sensor flip.
+        *
+        * Using ISP flip retains the BGGR pattern at the cost of changing the
+        * pixel array readout. This affects the selection rectangles in ways
+        * that are not very well documented, and would be tougher to deal with
+        * for applications compared to reading a different bayer pattern.
+        */
+       ret = ov5647_read(sd, reg, &reg_val);
+       if (ret)
+               return ret;
+
+       return ov5647_write(sd, reg, ctrl_val ? reg_val | BIT(1)
+                                             : reg_val & ~BIT(1));
+}
+
 static int ov5647_s_ctrl(struct v4l2_ctrl *ctrl)
 {
        struct ov5647 *sensor = container_of(ctrl->handler,
@@ -1291,6 +1344,14 @@ static int ov5647_s_ctrl(struct v4l2_ctrl *ctrl)
                /* Read-only, but we adjust it based on mode. */
                break;
 
+       case V4L2_CID_HFLIP:
+               /* There's an in-built hflip in the sensor, so account for that here. */
+               ret = ov5647_s_flip(sd, OV5647_REG_TIMING_TC_H, !ctrl->val);
+               break;
+       case V4L2_CID_VFLIP:
+               ret = ov5647_s_flip(sd, OV5647_REG_TIMING_TC_V, ctrl->val);
+               break;
+
        default:
                dev_info(&client->dev,
                         "Control (id:0x%x, val:0x%x) not supported\n",
@@ -1324,7 +1385,7 @@ static int ov5647_init_controls(struct ov5647 *sensor)
        int hblank, exposure_max, exposure_def;
        struct device *dev = &client->dev;
 
-       v4l2_ctrl_handler_init(&sensor->ctrls, 11);
+       v4l2_ctrl_handler_init(&sensor->ctrls, 13);
 
        v4l2_ctrl_new_std(&sensor->ctrls, &ov5647_ctrl_ops,
                          V4L2_CID_AUTOGAIN, 0, 1, 1, 0);
@@ -1373,6 +1434,12 @@ static int ov5647_init_controls(struct ov5647 *sensor)
                                     ARRAY_SIZE(ov5647_test_pattern_menu) - 1,
                                     0, 0, ov5647_test_pattern_menu);
 
+       sensor->hflip = v4l2_ctrl_new_std(&sensor->ctrls, &ov5647_ctrl_ops,
+                                         V4L2_CID_HFLIP, 0, 1, 1, 0);
+
+       sensor->vflip = v4l2_ctrl_new_std(&sensor->ctrls, &ov5647_ctrl_ops,
+                                         V4L2_CID_VFLIP, 0, 1, 1, 0);
+
        v4l2_fwnode_device_parse(dev, &props);
 
        v4l2_ctrl_new_fwnode_properties(&sensor->ctrls, &ov5647_ctrl_ops,