media: ov8856: Set default mbus format but allow caller to alter

Setting the value of V_WIN_OFF (0x3818) from 0x02 to 0x01 to use GRBG
format still results in wrong color output if data is tuned in BGGR mode
before.

Set default mbus format for the supported modes, but allow the caller of
set(get)_fmt to change the bayer format between BGGR and GRBG.

Set the default mbus format for 3264x2448 (and 1632x1224) to BGGR as the
data sheet states the value of this reg should be 0x02 by default.

If new modes are added in the future, they can add the
mipi_data_mbus_{format} settings into bayer_offset_configs to adjust their
offset regs.

Fixes: 2984b0ddd557 ("media: ov8856: Configure sensor for GRBG Bayer for all modes")
Signed-off-by: Hsin-Yi Wang <[e-mail]>
Reviewed-by: Robert Foss <[e-mail]>
Signed-off-by: Sakari Ailus <[e-mail]>
Signed-off-by: Mauro Carvalho Chehab <[e-mail]>

drivers/media/i2c/ov8856.c

···
 	"dvdd",		/* Digital core power */
 };
 
+enum {
+	OV8856_MEDIA_BUS_FMT_SBGGR10_1X10,
+	OV8856_MEDIA_BUS_FMT_SGRBG10_1X10,
+};
+
 struct ov8856_reg {
 	u16 address;
 	u8 val;
···
 
 	/* Number of data lanes */
 	u8 data_lanes;
+
+	/* Default MEDIA_BUS_FMT for this mode */
+	u32 default_mbus_index;
 };
 
 struct ov8856_mipi_data_rates {
···
 		{0x3810, 0x00},
 		{0x3811, 0x04},
 		{0x3812, 0x00},
-		{0x3813, 0x01},
+		{0x3813, 0x02},
 		{0x3814, 0x01},
 		{0x3815, 0x01},
 		{0x3816, 0x00},
···
 		{0x3810, 0x00},
 		{0x3811, 0x02},
 		{0x3812, 0x00},
-		{0x3813, 0x01},
+		{0x3813, 0x02},
 		{0x3814, 0x03},
 		{0x3815, 0x01},
 		{0x3816, 0x00},
···
 		{0x5e10, 0xfc}
 };
 
+static const struct ov8856_reg mipi_data_mbus_sbggr10_1x10[] = {
+	{0x3813, 0x02},
+};
+
+static const struct ov8856_reg mipi_data_mbus_sgrbg10_1x10[] = {
+	{0x3813, 0x01},
+};
+
+static const u32 ov8856_mbus_codes[] = {
+	MEDIA_BUS_FMT_SBGGR10_1X10,
+	MEDIA_BUS_FMT_SGRBG10_1X10
+};
+
 static const char * const ov8856_test_pattern_menu[] = {
 	"Disabled",
 	"Standard Color Bar",
 	"Top-Bottom Darker Color Bar",
 	"Right-Left Darker Color Bar",
 	"Bottom-Top Darker Color Bar"
+};
+
+static const struct ov8856_reg_list bayer_offset_configs[] = {
+	[OV8856_MEDIA_BUS_FMT_SBGGR10_1X10] = {
+		.num_of_regs = ARRAY_SIZE(mipi_data_mbus_sbggr10_1x10),
+		.regs = mipi_data_mbus_sbggr10_1x10,
+	},
+	[OV8856_MEDIA_BUS_FMT_SGRBG10_1X10] = {
+		.num_of_regs = ARRAY_SIZE(mipi_data_mbus_sgrbg10_1x10),
+		.regs = mipi_data_mbus_sgrbg10_1x10,
+	}
 };
 
 struct ov8856 {
···
 
 	/* Current mode */
 	const struct ov8856_mode *cur_mode;
+
+	/* Application specified mbus format */
+	u32 cur_mbus_index;
 
 	/* To serialize asynchronus callbacks */
 	struct mutex mutex;
···
 		},
 		.link_freq_index = 0,
 		.data_lanes = 2,
+		.default_mbus_index = OV8856_MEDIA_BUS_FMT_SGRBG10_1X10,
 	},
 	{
 		.width = 1640,
···
 		},
 		.link_freq_index = 1,
 		.data_lanes = 2,
+		.default_mbus_index = OV8856_MEDIA_BUS_FMT_SGRBG10_1X10,
 	}}
 };
 
···
 			},
 			.link_freq_index = 0,
 			.data_lanes = 4,
+			.default_mbus_index = OV8856_MEDIA_BUS_FMT_SGRBG10_1X10,
 		},
 		{
 			.width = 1640,
···
 			},
 			.link_freq_index = 1,
 			.data_lanes = 4,
+			.default_mbus_index = OV8856_MEDIA_BUS_FMT_SGRBG10_1X10,
 		},
 		{
 			.width = 3264,
···
 			},
 			.link_freq_index = 0,
 			.data_lanes = 4,
+			.default_mbus_index = OV8856_MEDIA_BUS_FMT_SBGGR10_1X10,
 		},
 		{
 			.width = 1632,
···
 			},
 			.link_freq_index = 1,
 			.data_lanes = 4,
+			.default_mbus_index = OV8856_MEDIA_BUS_FMT_SBGGR10_1X10,
 		}}
 };
 
···
 	return 0;
 }
 
-static void ov8856_update_pad_format(const struct ov8856_mode *mode,
+static void ov8856_update_pad_format(struct ov8856 *ov8856,
+				     const struct ov8856_mode *mode,
 				     struct v4l2_mbus_framefmt *fmt)
 {
+	int index;
+
 	fmt->width = mode->width;
 	fmt->height = mode->height;
-	fmt->code = MEDIA_BUS_FMT_SGRBG10_1X10;
+	for (index = 0; index < ARRAY_SIZE(ov8856_mbus_codes); ++index)
+		if (ov8856_mbus_codes[index] == fmt->code)
+			break;
+	if (index == ARRAY_SIZE(ov8856_mbus_codes))
+		index = mode->default_mbus_index;
+	fmt->code = ov8856_mbus_codes[index];
+	ov8856->cur_mbus_index = index;
 	fmt->field = V4L2_FIELD_NONE;
 }
 
···
 	ret = ov8856_write_reg_list(ov8856, reg_list);
 	if (ret) {
 		dev_err(&client->dev, "failed to set mode");
+		return ret;
+	}
+
+	reg_list = &bayer_offset_configs[ov8856->cur_mbus_index];
+	ret = ov8856_write_reg_list(ov8856, reg_list);
+	if (ret) {
+		dev_err(&client->dev, "failed to set mbus format");
 		return ret;
 	}
 
···
 				      fmt->format.height);
 
 	mutex_lock(&ov8856->mutex);
-	ov8856_update_pad_format(mode, &fmt->format);
+	ov8856_update_pad_format(ov8856, mode, &fmt->format);
 	if (fmt->which == V4L2_SUBDEV_FORMAT_TRY) {
 		*v4l2_subdev_get_try_format(sd, sd_state, fmt->pad) = fmt->format;
 	} else {
···
 							  sd_state,
 							  fmt->pad);
 	else
-		ov8856_update_pad_format(ov8856->cur_mode, &fmt->format);
+		ov8856_update_pad_format(ov8856, ov8856->cur_mode, &fmt->format);
 
 	mutex_unlock(&ov8856->mutex);
 
···
 				 struct v4l2_subdev_state *sd_state,
 				 struct v4l2_subdev_mbus_code_enum *code)
 {
-	/* Only one bayer order GRBG is supported */
-	if (code->index > 0)
+	if (code->index >= ARRAY_SIZE(ov8856_mbus_codes))
 		return -EINVAL;
 
-	code->code = MEDIA_BUS_FMT_SGRBG10_1X10;
+	code->code = ov8856_mbus_codes[code->index];
 
 	return 0;
 }
···
 				  struct v4l2_subdev_frame_size_enum *fse)
 {
 	struct ov8856 *ov8856 = to_ov8856(sd);
+	int index;
 
 	if (fse->index >= ov8856->modes_size)
 		return -EINVAL;
 
-	if (fse->code != MEDIA_BUS_FMT_SGRBG10_1X10)
+	for (index = 0; index < ARRAY_SIZE(ov8856_mbus_codes); ++index)
+		if (fse->code == ov8856_mbus_codes[index])
+			break;
+	if (index == ARRAY_SIZE(ov8856_mbus_codes))
 		return -EINVAL;
 
 	fse->min_width = ov8856->priv_lane->supported_modes[fse->index].width;
···
 	struct ov8856 *ov8856 = to_ov8856(sd);
 
 	mutex_lock(&ov8856->mutex);
-	ov8856_update_pad_format(&ov8856->priv_lane->supported_modes[0],
+	ov8856_update_pad_format(ov8856, &ov8856->priv_lane->supported_modes[0],
 				 v4l2_subdev_get_try_format(sd, fh->state, 0));
 	mutex_unlock(&ov8856->mutex);
 
···
 
 	mutex_init(&ov8856->mutex);
 	ov8856->cur_mode = &ov8856->priv_lane->supported_modes[0];
+	ov8856->cur_mbus_index = ov8856->cur_mode->default_mbus_index;
 	ret = ov8856_init_controls(ov8856);
 	if (ret) {
 		dev_err(&client->dev, "failed to init controls: %d", ret);