[PATCH v1 2/2] media: hi846: preserve the streaming state during system suspend

From: Martin Kepplinger
Date: Wed Apr 05 2023 - 05:39:03 EST


The hi846 driver changed the "streaming" state inside of "start/stop_streaming".
The problem is that inside of the (system) suspend callback, it calls
"stop_streaming" unconditionally. So streaming would always be stopped
when suspending.

That makes sense with runtime pm for example, after s_stream(..., 0) but
does not preserve the "streaming" state during system suspend when
currently streaming.

Fix this by simply setting the streaming state outside of "start/stop_streaming"
which is s_stream().

While at it, improve things a bit by not assigning "1", but the "enable"
value we later compare against, and fix one error handling path in resume().

Signed-off-by: Martin Kepplinger <martin.kepplinger@xxxxxxx>
---
drivers/media/i2c/hi846.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/media/i2c/hi846.c b/drivers/media/i2c/hi846.c
index 0b0eda2e223cd..1ca6e9407d618 100644
--- a/drivers/media/i2c/hi846.c
+++ b/drivers/media/i2c/hi846.c
@@ -1780,8 +1780,6 @@ static int hi846_start_streaming(struct hi846 *hi846)
return ret;
}

- hi846->streaming = 1;
-
dev_dbg(&client->dev, "%s: started streaming successfully\n", __func__);

return ret;
@@ -1793,8 +1791,6 @@ static void hi846_stop_streaming(struct hi846 *hi846)

if (hi846_write_reg(hi846, HI846_REG_MODE_SELECT, HI846_MODE_STANDBY))
dev_err(&client->dev, "failed to stop stream");
-
- hi846->streaming = 0;
}

static int hi846_set_stream(struct v4l2_subdev *sd, int enable)
@@ -1816,10 +1812,12 @@ static int hi846_set_stream(struct v4l2_subdev *sd, int enable)
}

ret = hi846_start_streaming(hi846);
+ hi846->streaming = enable;
}

if (!enable || ret) {
hi846_stop_streaming(hi846);
+ hi846->streaming = 0;
pm_runtime_put(&client->dev);
}

@@ -1898,6 +1896,8 @@ static int __maybe_unused hi846_resume(struct device *dev)
if (ret) {
dev_err(dev, "%s: start streaming failed: %d\n",
__func__, ret);
+ hi846_stop_streaming(hi846);
+ hi846->streaming = 0;
goto error;
}
}
--
2.30.2