[PATCH v2 1/5] media: mt9p031: Add support for 8 bit and 10 bit formats

[Stefan Riedmueller <s.riedmueller@xxxxxxxxx>]

From: Christian Hemp <c.hemp@xxxxxxxxx>

Aside from 12 bit monochrome or color format the sensor implicitly
supports 10 and 8 bit formats as well by simply dropping the
corresponding LSBs.

Signed-off-by: Christian Hemp <c.hemp@xxxxxxxxx>
[jlu@xxxxxxxxxxxxxx: simplified by dropping v4l2_colorspace handling]
Signed-off-by: Jan Luebbe <jlu@xxxxxxxxxxxxxx>
Signed-off-by: Stefan Riedmueller <s.riedmueller@xxxxxxxxx>
---
Changes in v2:
 - Use unsigned int for num_fmts and loop variable in find_datafmt
 - Remove superfluous const qualifier from find_datafmt
---
 drivers/media/i2c/mt9p031.c | 50 +++++++++++++++++++++++++++++--------
 1 file changed, 40 insertions(+), 10 deletions(-)

diff --git a/drivers/media/i2c/mt9p031.c b/drivers/media/i2c/mt9p031.c
index dc23b9ed510a..2e6671ef877c 100644
--- a/drivers/media/i2c/mt9p031.c
+++ b/drivers/media/i2c/mt9p031.c
@@ -116,6 +116,18 @@ enum mt9p031_model {
 	MT9P031_MODEL_MONOCHROME,
 };
 
+static const u32 mt9p031_color_fmts[] = {
+	MEDIA_BUS_FMT_SGRBG8_1X8,
+	MEDIA_BUS_FMT_SGRBG10_1X10,
+	MEDIA_BUS_FMT_SGRBG12_1X12,
+};
+
+static const u32 mt9p031_monochrome_fmts[] = {
+	MEDIA_BUS_FMT_Y8_1X8,
+	MEDIA_BUS_FMT_Y10_1X10,
+	MEDIA_BUS_FMT_Y12_1X12,
+};
+
 struct mt9p031 {
 	struct v4l2_subdev subdev;
 	struct media_pad pad;
@@ -138,6 +150,9 @@ struct mt9p031 {
 	struct v4l2_ctrl *blc_auto;
 	struct v4l2_ctrl *blc_offset;
 
+	const u32 *fmts;
+	unsigned int num_fmts;
+
 	/* Registers cache */
 	u16 output_control;
 	u16 mode2;
@@ -148,6 +163,17 @@ static struct mt9p031 *to_mt9p031(struct v4l2_subdev *sd)
 	return container_of(sd, struct mt9p031, subdev);
 }
 
+static u32 mt9p031_find_datafmt(struct mt9p031 *mt9p031, u32 code)
+{
+	unsigned int i;
+
+	for (i = 0; i < mt9p031->num_fmts; i++)
+		if (mt9p031->fmts[i] == code)
+			return mt9p031->fmts[i];
+
+	return mt9p031->fmts[mt9p031->num_fmts-1];
+}
+
 static int mt9p031_read(struct i2c_client *client, u8 reg)
 {
 	return i2c_smbus_read_word_swapped(client, reg);
@@ -476,10 +502,11 @@ static int mt9p031_enum_mbus_code(struct v4l2_subdev *subdev,
 {
 	struct mt9p031 *mt9p031 = to_mt9p031(subdev);
 
-	if (code->pad || code->index)
+	if (code->pad || code->index >= mt9p031->num_fmts)
 		return -EINVAL;
 
-	code->code = mt9p031->format.code;
+	code->code = mt9p031->fmts[code->index];
+
 	return 0;
 }
 
@@ -573,6 +600,8 @@ static int mt9p031_set_format(struct v4l2_subdev *subdev,
 	__format->width = __crop->width / hratio;
 	__format->height = __crop->height / vratio;
 
+	__format->code = mt9p031_find_datafmt(mt9p031, format->format.code);
+
 	format->format = *__format;
 
 	return 0;
@@ -951,10 +980,7 @@ static int mt9p031_open(struct v4l2_subdev *subdev, struct v4l2_subdev_fh *fh)
 
 	format = v4l2_subdev_get_try_format(subdev, fh->pad, 0);
 
-	if (mt9p031->model == MT9P031_MODEL_MONOCHROME)
-		format->code = MEDIA_BUS_FMT_Y12_1X12;
-	else
-		format->code = MEDIA_BUS_FMT_SGRBG12_1X12;
+	format->code = mt9p031_find_datafmt(mt9p031, 0);
 
 	format->width = MT9P031_WINDOW_WIDTH_DEF;
 	format->height = MT9P031_WINDOW_HEIGHT_DEF;
@@ -1121,10 +1147,14 @@ static int mt9p031_probe(struct i2c_client *client,
 	mt9p031->crop.left = MT9P031_COLUMN_START_DEF;
 	mt9p031->crop.top = MT9P031_ROW_START_DEF;
 
-	if (mt9p031->model == MT9P031_MODEL_MONOCHROME)
-		mt9p031->format.code = MEDIA_BUS_FMT_Y12_1X12;
-	else
-		mt9p031->format.code = MEDIA_BUS_FMT_SGRBG12_1X12;
+	if (mt9p031->model == MT9P031_MODEL_MONOCHROME) {
+		mt9p031->fmts = mt9p031_monochrome_fmts;
+		mt9p031->num_fmts = ARRAY_SIZE(mt9p031_monochrome_fmts);
+	} else {
+		mt9p031->fmts = mt9p031_color_fmts;
+		mt9p031->num_fmts = ARRAY_SIZE(mt9p031_color_fmts);
+	}
+	mt9p031->format.code = mt9p031_find_datafmt(mt9p031, 0);
 
 	mt9p031->format.width = MT9P031_WINDOW_WIDTH_DEF;
 	mt9p031->format.height = MT9P031_WINDOW_HEIGHT_DEF;
-- 
2.25.1