Integer controls provide a way to get their default/initial value, but any other control (p_u32, p_u8.....) provide no other way to get the initial value than unloading the module and loading it back. *What is the actual problem? I have a custom control with WIDTH integer values. Every value represents the calibrated FPN (fixed pattern noise) correction value for that column -Application A changes the FPN correction value -Application B wants to restore the calibrated value but it cant :( *What is the proposed solution? -Add a new ioctl VIDIOC_G_DEF_EXT_CTRLS, with the same API as G_EXT_CTRLS, but that returns the initial value of a given control. I have posted a copy of my working tree to https://github.com/ribalda/linux/tree/g_def_ext It has been tested with a hacked version of yavta (for normal controls) and a custom program for the array control. Changelog v2: -Add documentation -Split in multiple patches -Comments by Hans: -Rename ioctl to G_DEF_EXT_CTRL -Much! better implementation of def_to_user THANKS! Ricardo Ribalda Delgado (27): media/v4l2-core: Add argument def_value to g_ext_ctrl media/v4l2-core: add new ioctl VIDIOC_G_DEF_EXT_CTRLS videodev2.h: Fix typo in comment v4l2-subdev: Add g_def_ext_ctrls to core_ops media/i2c/adv7343: Implement g_def_ext_ctrls core_op media/i2c/adv7393: Implement g_def_ext_ctrls core_op media/i2c/bt819: Implement g_def_ext_ctrls core_op media/i2c/cs5345: Implement g_def_ext_ctrls core_op media/i2c/cs53l32a: Implement g_def_ext_ctrls core_op media/i2c/cx25840/cx25840-core: Implement g_def_ext_ctrls core_op media/i2c/msp3400-driver: Implement g_def_ext_ctrls core_op media/i2c/saa7110: Implement g_def_ext_ctrls core_op media/i2c/saa7115: Implement g_def_ext_ctrls core_op media/i2c/saa717x: Implement g_def_ext_ctrls core_op media/i2c/sr030pc30: Implement g_def_ext_ctrls core_op media/i2c/tda7432: Implement g_def_ext_ctrls core_op media/i2c/tlv320aic23b: Implement g_def_ext_ctrls core_op media/i2c/tvaudio: Implement g_def_ext_ctrls core_op media/i2c/tvp514x: Implement g_def_ext_ctrls core_op media/i2c/tvp7002: Implement g_def_ext_ctrls core_op media/i2c/vpx3220: Implement g_def_ext_ctrls core_op media/i2c/wm8739: Implement g_def_ext_ctrls core_op media/i2c/wm8775: Implement g_def_ext_ctrls core_op media/pci/ivtv/ivtv-gpio: Implement g_def_ext_ctrls core_op media/radio/saa7706h: Implement g_def_ext_ctrls core_op Docbook: media: new ioctl VIDIOC_G_DEF_EXT_CTRLS Documentation: media: Fix code sample Documentation/DocBook/media/v4l/v4l2.xml | 8 ++++++ .../DocBook/media/v4l/vidioc-g-ext-ctrls.xml | 13 ++++++--- Documentation/video4linux/v4l2-controls.txt | 4 ++- Documentation/video4linux/v4l2-framework.txt | 1 + Documentation/zh_CN/video4linux/v4l2-framework.txt | 1 + drivers/media/i2c/adv7343.c | 1 + drivers/media/i2c/adv7393.c | 1 + drivers/media/i2c/bt819.c | 1 + drivers/media/i2c/cs5345.c | 1 + drivers/media/i2c/cs53l32a.c | 1 + drivers/media/i2c/cx25840/cx25840-core.c | 1 + drivers/media/i2c/msp3400-driver.c | 1 + drivers/media/i2c/saa7110.c | 1 + drivers/media/i2c/saa7115.c | 1 + drivers/media/i2c/saa717x.c | 1 + drivers/media/i2c/sr030pc30.c | 1 + drivers/media/i2c/tda7432.c | 1 + drivers/media/i2c/tlv320aic23b.c | 1 + drivers/media/i2c/tvaudio.c | 1 + drivers/media/i2c/tvp514x.c | 1 + drivers/media/i2c/tvp7002.c | 1 + drivers/media/i2c/vpx3220.c | 1 + drivers/media/i2c/wm8739.c | 1 + drivers/media/i2c/wm8775.c | 1 + drivers/media/pci/ivtv/ivtv-gpio.c | 1 + drivers/media/platform/omap3isp/ispvideo.c | 2 +- drivers/media/radio/saa7706h.c | 1 + drivers/media/v4l2-core/v4l2-compat-ioctl32.c | 4 +++ drivers/media/v4l2-core/v4l2-ctrls.c | 32 ++++++++++++++++++---- drivers/media/v4l2-core/v4l2-ioctl.c | 25 +++++++++++++++-- drivers/media/v4l2-core/v4l2-subdev.c | 5 +++- include/media/v4l2-ctrls.h | 5 +++- include/media/v4l2-ioctl.h | 2 ++ include/media/v4l2-subdev.h | 2 ++ include/uapi/linux/videodev2.h | 3 +- 35 files changed, 112 insertions(+), 16 deletions(-) -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html