Hi Laurent On Mon, 21 Aug 2023 at 23:30, Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> wrote: > > There is no need to stop streaming at system suspend time, or restart it > when the system is resumed, as the host-side driver is responsible for > stopping and restarting the pipeline in a controlled way by calling the > .s_stream() operation. Drop the system suspend and resume handlers, and > simplify the .s_stream() handler as a result. I'll believe you, but the docs for power management in camera sensor drivers [1] state "Please see examples in e.g. drivers/media/i2c/ov8856.c and drivers/media/i2c/ccs/ccs-core.c. The two drivers work in both ACPI and DT based systems." Looking at CCS we find the suspend hook stopping streaming [2], and resume hook starting it [3]. Same in ov8856 [4]. Could you reference the documentation that states that the host-side driver is responsible for starting and stopping? Is this an ACPI vs DT difference? Functionally the patch does what you say, so would get a R-b tag otherwise. Dave [1] https://www.kernel.org/doc/html/latest/driver-api/media/camera-sensor.html#power-management [2] https://github.com/torvalds/linux/blob/master/drivers/media/i2c/ccs/ccs-core.c#L3155-L3173 [3] https://github.com/torvalds/linux/blob/master/drivers/media/i2c/ccs/ccs-core.c#L3185-L3186 [4] https://github.com/torvalds/linux/blob/master/drivers/media/i2c/ov8856.c#L2128-L2164 > Signed-off-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> > --- > drivers/media/i2c/imx219.c | 56 ++------------------------------------ > 1 file changed, 2 insertions(+), 54 deletions(-) > > diff --git a/drivers/media/i2c/imx219.c b/drivers/media/i2c/imx219.c > index 227c227cf4ce..da2a8d0210fa 100644 > --- a/drivers/media/i2c/imx219.c > +++ b/drivers/media/i2c/imx219.c > @@ -359,9 +359,6 @@ struct imx219 { > struct v4l2_ctrl *vblank; > struct v4l2_ctrl *hblank; > > - /* Streaming on/off */ > - bool streaming; > - > /* Two or Four lanes */ > u8 lanes; > }; > @@ -764,24 +761,11 @@ static int imx219_set_stream(struct v4l2_subdev *sd, int enable) > > state = v4l2_subdev_lock_and_get_active_state(sd); > > - if (imx219->streaming == enable) > - goto unlock; > - > - if (enable) { > - /* > - * Apply default & customized values > - * and then start streaming. > - */ > + if (enable) > ret = imx219_start_streaming(imx219, state); > - if (ret) > - goto unlock; > - } else { > + else > imx219_stop_streaming(imx219); > - } > > - imx219->streaming = enable; > - > -unlock: > v4l2_subdev_unlock_state(state); > return ret; > } > @@ -1015,41 +999,6 @@ static int imx219_power_off(struct device *dev) > return 0; > } > > -static int __maybe_unused imx219_suspend(struct device *dev) > -{ > - struct v4l2_subdev *sd = dev_get_drvdata(dev); > - struct imx219 *imx219 = to_imx219(sd); > - > - if (imx219->streaming) > - imx219_stop_streaming(imx219); > - > - return 0; > -} > - > -static int __maybe_unused imx219_resume(struct device *dev) > -{ > - struct v4l2_subdev *sd = dev_get_drvdata(dev); > - struct imx219 *imx219 = to_imx219(sd); > - struct v4l2_subdev_state *state; > - int ret; > - > - if (imx219->streaming) { > - state = v4l2_subdev_lock_and_get_active_state(sd); > - ret = imx219_start_streaming(imx219, state); > - v4l2_subdev_unlock_state(state); > - if (ret) > - goto error; > - } > - > - return 0; > - > -error: > - imx219_stop_streaming(imx219); > - imx219->streaming = false; > - > - return ret; > -} > - > /* ----------------------------------------------------------------------------- > * Probe & remove > */ > @@ -1295,7 +1244,6 @@ static const struct of_device_id imx219_dt_ids[] = { > MODULE_DEVICE_TABLE(of, imx219_dt_ids); > > static const struct dev_pm_ops imx219_pm_ops = { > - SET_SYSTEM_SLEEP_PM_OPS(imx219_suspend, imx219_resume) > SET_RUNTIME_PM_OPS(imx219_power_off, imx219_power_on, NULL) > }; > > -- > Regards, > > Laurent Pinchart >
