Hi Ricardo, On Wed, 2023-06-14 at 17:25 +0200, Ricardo Ribalda wrote: > On Wed, 14 Jun 2023 at 17:22, Gergo Koteles <soyer@xxxxxx> wrote: > > > > Hi Ricardo, > > On Wed, 2023-06-14 at 17:08 +0200, Ricardo Ribalda wrote: > > > On Wed, 14 Jun 2023 at 17:07, Ricardo Ribalda > > > <ribalda@xxxxxxxxxxxx> > > > wrote: > > > > > > > > Hi Soyer > > > > > > > > > > > > On Wed, 14 Jun 2023 at 16:59, soyer <soyer@xxxxxx> wrote: > > > > > > > > > > Hi Ricardo > > > > > > > > > > On Wed, 2023-06-14 at 16:19 +0200, Ricardo Ribalda wrote: > > > > > > [Now in plain text mode] > > > > > > > > > > > > Hi Gergo > > > > > > > > > > > > Doesn't your patch affect pan and tilt for all the cameras, > > > > > > not > > > > > > only > > > > > > the BCC950? > > > > > > > > > > > Yes, it affects all cameras that support > > > > > CT_PANTILT_RELATIVE_CONTROL. > > > > > > > > > > > Also it seems that 1 means that device does not support > > > > > > programmable > > > > > > speed. Is that correct? > > > > > > > > > > > > ``` > > > > > > The bPanSpeed field is used to specify the speed of the > > > > > > movement for > > > > > > the Pan direction. A low > > > > > > number indicates a slow speed and a high number indicates a > > > > > > higher > > > > > > speed. The GET_MIN, > > > > > > GET_MAX and GET_RES requests are used to retrieve the range > > > > > > and > > > > > > resolution for this field. > > > > > > The GET_DEF request is used to retrieve the default value > > > > > > for > > > > > > this > > > > > > field. If the control does not > > > > > > support speed control for the Pan control, it will return > > > > > > the > > > > > > value 1 > > > > > > in this field for all these > > > > > > requests. > > > > > > ``` > > > > > > > > It seems to me that the module is compliant to the standard. It > > > > returns 1 as GET_DEF because it does not support speed control. > > > > > > > > Maybe you should ignore the speed control instead of changing > > > > its > > > > default value? > > > > > > ( this is the standard I am refering to: 4.2.2.1.15 PanTilt > > > (Relative) Control > > > > > > > > > https://www.usb.org/document-library/video-class-v15-document-set ; > > > ) > > > > > > > > > > > > It's a different API. V4L2 control values are not the same as the > > UVC > > standard control values. > > What I am saying, is that if > CT_PANTILT_RELATIVE_CONTROL.bPanSpeed.GET_DEF is 1 you should not > create the mapping to > V4L2_CID_PAN_SPEED > If I set V4L2_CID_PAN_SPEED to 1 (max), the BCC950 starts to move at maximum speed. This is what it should do according to description of the V4L2_CID_PAN_SPEED. My understanding is that, if the camera supports CT_PANTILT_RELATIVE_CONTROL there should be a V4L2_CID_PAN_SPEED. CT_PANTILT_RELATIVE_CONTROL.bPanSpeed.GET_DEF == 1 only says that only one speed is available not a range. > > > > Eg the V4L2_CID_PAN_SPEED control value calculated from > > CT_PANTILT_RELATIVE_CONTROL's bPanRelative and bPanSpeed value. > > > > It only bothers me that I have to handle these two controls > > differently. > > > > > > > > > > > > > I started from the V4L2 control description. > > > > > > > > > > V4L2_CID_PAN_SPEED (integer) > > > > > This control turns the camera horizontally at the specific > > > > > speed. > > > > > The > > > > > unit is undefined. A positive value moves the camera to the > > > > > right > > > > > (clockwise when viewed from above), a negative value to the > > > > > left. > > > > > A > > > > > value of zero stops the motion if one is in progress and has > > > > > no > > > > > effect > > > > > otherwise. > > > > > > > > > > And this is why I thought that 1 is not a good default value, > > > > > because > > > > > it moves the camera. > > > > > The other V4L2 controls have a default value that I can > > > > > safely > > > > > set the > > > > > controls to. > > > > > > > > > > Are you using it to determine if the camera supports speed > > > > > control? > > > > > > > > > > > When you program that value do you see any difference on > > > > > > the > > > > > > device? > > > > > > What is max, min and res? > > > > > > > > > > > > > > > > No, it works the same way. > > > > > Only the default value changes (from 1 to 0) > > > > > > > > > > pan_speed 0x009a0920 (int) : min=-1 max=1 step=1 > > > > > default=0 > > > > > value=0 > > > > > tilt_speed 0x009a0921 (int) : min=-1 max=1 step=1 > > > > > default=0 > > > > > value=0 > > > > > > > > > > > > > > > > > > > > > > > > > > > Thanks! > > > > > > > > > > > > Regards! > > > > > > > > > > > > > > > > > > > > > > Thanks, > > > > > Gergo > > > > > > > > > > > On Wed, 14 Jun 2023 at 15:13, Gergo Koteles <soyer@xxxxxx> > > > > > > wrote: > > > > > > > > > > > > > > The Logitech BCC950 incorrectly reports 1 (the max value) > > > > > > > for the default values of V4L2_CID_PAN_SPEED, > > > > > > > V4L2_CID_TILT_SPEED. > > > > > > > > > > > > > > This patch sets them to 0, which is the stop value. > > > > > > > > > > > > > > Previous discussion > > > > > > > Link: > > > > > > > https://lore.kernel.org/all/CAP_ceTy6XVmvTTAmvCp1YU2wxHwXqnarm69Yaz8K4FmpJqYxAg@xxxxxxxxxxxxxx/ > > > > > > > > > > > > > > Signed-off-by: Gergo Koteles <soyer@xxxxxx> > > > > > > > --- > > > > > > > drivers/media/usb/uvc/uvc_ctrl.c | 3 ++- > > > > > > > 1 file changed, 2 insertions(+), 1 deletion(-) > > > > > > > > > > > > > > diff --git a/drivers/media/usb/uvc/uvc_ctrl.c > > > > > > > b/drivers/media/usb/uvc/uvc_ctrl.c > > > > > > > index 5e9d3da862dd..e131958c0930 100644 > > > > > > > --- a/drivers/media/usb/uvc/uvc_ctrl.c > > > > > > > +++ b/drivers/media/usb/uvc/uvc_ctrl.c > > > > > > > @@ -444,9 +444,10 @@ static s32 > > > > > > > uvc_ctrl_get_rel_speed(struct > > > > > > > uvc_control_mapping *mapping, > > > > > > > return -data[first+1]; > > > > > > > case UVC_GET_MAX: > > > > > > > case UVC_GET_RES: > > > > > > > + return data[first+1]; > > > > > > > case UVC_GET_DEF: > > > > > > > default: > > > > > > > - return data[first+1]; > > > > > > > + return 0; > > > > > > > } > > > > > > > } > > > > > > > > > > > > > > > > > > > > > base-commit: be9aac187433af6abba5fcc2e73d91d0794ba360 > > > > > > > -- > > > > > > > 2.40.1 > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > -- > > > > Ricardo Ribalda > > > > > > > > > > > > >