linux-kernel - [PATCH v2 3/3] media: mt9m111: don't turn on the output while powering it

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Date:   Fri, 16 Sep 2022 15:57:13 +0200
From:   Marco Felsch <m.felsch@...gutronix.de>
To:     mchehab@...nel.org, sakari.ailus@...ux.intel.com,
        laurent.pinchart+renesas@...asonboard.com, akinobu.mita@...il.com,
        jacopo+renesas@...ndi.org
Cc:     linux-media@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: [PATCH v2 3/3] media: mt9m111: don't turn on the output while powering it

Currently the .s_power() turn on/off the device and enables/disables the
sensor output. This is wrong since it should only handle the power not
not the sensor output behaviour. Enabling the sensor output should be
part of the .s_stream() callback.

Fix this by adding mt9m111_set_output() which gets called by the
.s_stream() callback and remove the output register bits from
mt9m111_resume/suspend.

Signed-off-by: Marco Felsch <m.felsch@...gutronix.de>
---
Changelog:

v2:
- new patch, replaces: "media: mt9m111: remove .s_power callback"
---
 drivers/media/i2c/mt9m111.c | 38 ++++++++++++++++++++++++++-----------
 1 file changed, 27 insertions(+), 11 deletions(-)

diff --git a/drivers/media/i2c/mt9m111.c b/drivers/media/i2c/mt9m111.c
index 8de93ab99cbc..2cc0b0da7636 100644
--- a/drivers/media/i2c/mt9m111.c
+++ b/drivers/media/i2c/mt9m111.c
@@ -426,10 +426,25 @@ static int mt9m111_setup_geometry(struct mt9m111 *mt9m111, struct v4l2_rect *rec
 	return ret;
 }
 
-static int mt9m111_enable(struct mt9m111 *mt9m111)
+static int mt9m111_set_output(struct mt9m111 *mt9m111, int on)
 {
 	struct i2c_client *client = v4l2_get_subdevdata(&mt9m111->subdev);
-	return reg_write(RESET, MT9M111_RESET_CHIP_ENABLE);
+	int ret;
+
+	if (on) {
+		ret = reg_clear(RESET, MT9M111_RESET_OUTPUT_DISABLE);
+		if (ret)
+			return ret;
+
+		return reg_set(RESET, MT9M111_RESET_CHIP_ENABLE);
+	}
+
+	/* disable */
+	ret = reg_set(RESET, MT9M111_RESET_OUTPUT_DISABLE);
+	if (ret)
+		return ret;
+
+	return reg_clear(RESET, MT9M111_RESET_CHIP_ENABLE);
 }
 
 static int mt9m111_reset(struct mt9m111 *mt9m111)
@@ -927,10 +942,7 @@ static int mt9m111_suspend(struct mt9m111 *mt9m111)
 	ret = reg_set(RESET, MT9M111_RESET_RESET_MODE);
 	if (!ret)
 		ret = reg_set(RESET, MT9M111_RESET_RESET_SOC |
-			      MT9M111_RESET_OUTPUT_DISABLE |
 			      MT9M111_RESET_ANALOG_STANDBY);
-	if (!ret)
-		ret = reg_clear(RESET, MT9M111_RESET_CHIP_ENABLE);
 
 	return ret;
 }
@@ -951,9 +963,9 @@ static void mt9m111_restore_state(struct mt9m111 *mt9m111)
 
 static int mt9m111_resume(struct mt9m111 *mt9m111)
 {
-	int ret = mt9m111_enable(mt9m111);
-	if (!ret)
-		ret = mt9m111_reset(mt9m111);
+	int ret;
+
+	ret = mt9m111_reset(mt9m111);
 	if (!ret)
 		mt9m111_restore_state(mt9m111);
 
@@ -965,9 +977,7 @@ static int mt9m111_init(struct mt9m111 *mt9m111)
 	struct i2c_client *client = v4l2_get_subdevdata(&mt9m111->subdev);
 	int ret;
 
-	ret = mt9m111_enable(mt9m111);
-	if (!ret)
-		ret = mt9m111_reset(mt9m111);
+	ret = mt9m111_reset(mt9m111);
 	if (!ret)
 		ret = mt9m111_set_context(mt9m111, mt9m111->ctx);
 	if (ret)
@@ -1116,8 +1126,14 @@ static int mt9m111_enum_mbus_code(struct v4l2_subdev *sd,
 static int mt9m111_s_stream(struct v4l2_subdev *sd, int enable)
 {
 	struct mt9m111 *mt9m111 = container_of(sd, struct mt9m111, subdev);
+	int ret;
+
+	ret = mt9m111_set_output(mt9m111, enable);
+	if (ret)
+		return ret;
 
 	mt9m111->is_streaming = !!enable;
+
 	return 0;
 }
 
-- 
2.30.2