[PATCH 3/4] media: mt9m111: fix device power usage

[Marco Felsch <m.felsch@pengutronix.de>]

Currently the driver turn off the power after probe and toggle it during
.stream by using the .s_power callback. This is problematic since other
callbacks like .set_fmt accessing the hardware as well which will fail.
So in the end the default format is the only supported format.

Remove the hardware register access from the callbacks and instead sync
the state once right before the stream gets enabled to fix this.

Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
---
 drivers/media/i2c/mt9m111.c | 20 +++++++++++++-------
 1 file changed, 13 insertions(+), 7 deletions(-)

diff --git a/drivers/media/i2c/mt9m111.c b/drivers/media/i2c/mt9m111.c
index 53c4dac4e4bd..cd74c408e110 100644
--- a/drivers/media/i2c/mt9m111.c
+++ b/drivers/media/i2c/mt9m111.c
@@ -481,8 +481,6 @@ static int mt9m111_set_selection(struct v4l2_subdev *sd,
 	width = min(mt9m111->width, rect.width);
 	height = min(mt9m111->height, rect.height);
 
-
-	mt9m111_setup_geometry(mt9m111, &rect, width, height, mt9m111->fmt->code);
 	mt9m111->rect = rect;
 	mt9m111->width = width;
 	mt9m111->height = height;
@@ -611,7 +609,6 @@ static int mt9m111_set_pixfmt(struct mt9m111 *mt9m111,
 	if (mt9m111->pclk_sample == 0)
 		mask_outfmt2 |= MT9M111_OUTFMT_INV_PIX_CLOCK;
 
-
 	mt9m111_reg_mask(client, context_a.output_fmt_ctrl2,
 			 data_outfmt2, mask_outfmt2);
 	mt9m111_reg_mask(client, context_b.output_fmt_ctrl2,
@@ -678,9 +675,6 @@ static int mt9m111_set_fmt(struct v4l2_subdev *sd,
 		return 0;
 	}
 
-
-	mt9m111_setup_geometry(mt9m111, rect, mf->width, mf->height, mf->code);
-	mt9m111_set_pixfmt(mt9m111, mf->code);
 	mt9m111->width	= mf->width;
 	mt9m111->height	= mf->height;
 	mt9m111->fmt	= fmt;
@@ -743,6 +737,8 @@ mt9m111_find_mode(struct mt9m111 *mt9m111, unsigned int req_fps,
 	return mode;
 }
 
+static int mt9m111_s_power(struct v4l2_subdev *sd, int on);
+
 #ifdef CONFIG_VIDEO_ADV_DEBUG
 static int mt9m111_g_register(struct v4l2_subdev *sd,
 			      struct v4l2_dbg_register *reg)
@@ -753,10 +749,14 @@ static int mt9m111_g_register(struct v4l2_subdev *sd,
 	if (reg->reg > 0x2ff)
 		return -EINVAL;
 
+	mt9m111_s_power(sd, 1);
+
 	val = mt9m111_reg_read(client, reg->reg);
 	reg->size = 2;
 	reg->val = (u64)val;
 
+	mt9m111_s_power(sd, 0);
+
 	if (reg->val > 0xffff)
 		return -EIO;
 
@@ -771,9 +771,13 @@ static int mt9m111_s_register(struct v4l2_subdev *sd,
 	if (reg->reg > 0x2ff)
 		return -EINVAL;
 
+	mt9m111_s_power(sd, 1);
+
 	if (mt9m111_reg_write(client, reg->reg, reg->val) < 0)
 		return -EIO;
 
+	mt9m111_s_power(sd, 0);
+
 	return 0;
 }
 #endif
@@ -896,6 +900,9 @@ static int mt9m111_s_ctrl(struct v4l2_ctrl *ctrl)
 					       struct mt9m111, hdl);
 	int ret;
 
+	if (!mt9m111->is_streaming)
+		return 0;
+
 	switch (ctrl->id) {
 	case V4L2_CID_VFLIP:
 		ret = mt9m111_set_flip(mt9m111, ctrl->val,
@@ -927,7 +934,6 @@ static int mt9m111_s_ctrl(struct v4l2_ctrl *ctrl)
 		ret = -EINVAL;
 	}
 
-
 	return ret;
 }
 
-- 
2.30.2