| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <20251119042126.GJ10711@pendragon.ideasonboard.com>
Date: Wed, 19 Nov 2025 13:21:26 +0900
From: Laurent Pinchart <laurent.pinchart@...asonboard.com>
To: Ricardo Ribalda <ribalda@...omium.org>
Cc: Hans de Goede <hansg@...nel.org>,
Mauro Carvalho Chehab <mchehab@...nel.org>,
Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
linux-media@...r.kernel.org, linux-kernel@...r.kernel.org,
linux-usb@...r.kernel.org,
Manav Gautama <bandwidthcrunch@...il.com>,
Martin Rubli <martin_rubli@...itech.com>
Subject: Re: [PATCH 2/4] media: uvcvideo: Import standard controls from
uvcdynctrl
Hi Ricardo,
Thank you for the patch.
On Mon, Nov 17, 2025 at 08:14:17PM +0000, Ricardo Ribalda wrote:
> The uvcdynctrl tool from libwebcam:
> https://sourceforge.net/projects/libwebcam/
> maps proprietary controls into v4l2 controls using the UVCIOC_CTRL_MAP
> ioctl.
>
> The tool has not been updated for 10+ years now, and there is no reason
> for the UVC driver to not do the mapping by itself.
I'd expand this a bit for historians:
this was envisioned as the base of a vibrant ecosystem where a large
number of vendors would submit XML files that describe their XU control
mappings, at a pace faster than could be supported by adding XU mappings
to the driver. This vision failed to materialize and the tool has not
been updated for 10+ years now. There is no reason to believe the
situation will change.
> This patch adds the mappings from the uvcdynctrl into the driver. Hopefully
> this effort can help in deprecating the UVCIOC_CTRL_MAP ioctl.
>
> During the porting, the following mappings where NOT imported because
> they were not using standard v4l2 IDs. It is recommended that userspace
> moves to UVCIOC_CTRL_QUERY for non standard controls.
>
> {
> .id = V4L2_CID_FLASH_MODE,
> .entity = UVC_GUID_SIS_LED_HW_CONTROL,
> .selector = 4,
> .size = 4,
> .offset = 0,
> .v4l2_type = V4L2_CTRL_TYPE_MENU,
> .data_type = UVC_CTRL_DATA_TYPE_UNSIGNED,
> .menu_mask = 0x3,
> .menu_mapping = { 0x20, 0x22 },
> .menu_names = { "Off", "On" },
>
> },
> {
> .id = V4L2_CID_FLASH_FREQUENCY,
> .entity = UVC_GUID_SIS_LED_HW_CONTROL,
> .selector = 4,
> .size = 8,
> .offset = 16,
> .v4l2_type = V4L2_CTRL_TYPE_INTEGER,
> .data_type = UVC_CTRL_DATA_TYPE_UNSIGNED,
> },
> {
> .id = V4L2_CID_LED1_MODE,
> .entity = UVC_GUID_LOGITECH_USER_HW_CONTROL_V1,
> .selector = 1,
> .size = 8,
> .offset = 0,
> .v4l2_type = V4L2_CTRL_TYPE_MENU,
> .data_type = UVC_CTRL_DATA_TYPE_UNSIGNED,
> .menu_mask = 0xF,
> .menu_mapping = { 0, 1, 2, 3 },
> .menu_names = { "Off", "On", "Blinking", "Auto" },
>
> },
> {
> .id = V4L2_CID_LED1_FREQUENCY,
> .entity = UVC_GUID_LOGITECH_USER_HW_CONTROL_V1,
> .selector = 1,
> .size = 8,
> .offset = 16,
> .v4l2_type = V4L2_CTRL_TYPE_INTEGER,
> .data_type = UVC_CTRL_DATA_TYPE_UNSIGNED,
> },
> {
> .id = V4L2_CID_DISABLE_PROCESSING,
> .entity = UVC_GUID_LOGITECH_VIDEO_PIPE_V1,
> .selector = 5,
> .size = 8,
> .offset = 0,
> .v4l2_type = V4L2_CTRL_TYPE_BOOLEAN,
> .data_type = UVC_CTRL_DATA_TYPE_BOOLEAN,
> },
> {
> .id = V4L2_CID_RAW_BITS_PER_PIXEL,
> .entity = UVC_GUID_LOGITECH_VIDEO_PIPE_V1,
> .selector = 8,
> .size = 8,
> .offset = 0,
> .v4l2_type = V4L2_CTRL_TYPE_INTEGER,
> .data_type = UVC_CTRL_DATA_TYPE_UNSIGNED,
> },
> {
> .id = V4L2_CID_RAW_BITS_PER_PIXEL,
> .entity = UVC_GUID_LOGITECH_VIDEO_PIPE_V1,
> .selector = 8,
> .size = 8,
> .offset = 0,
> .v4l2_type = V4L2_CTRL_TYPE_INTEGER,
> .data_type = UVC_CTRL_DATA_TYPE_UNSIGNED,
> },
Duplicate control.
> {
> .id = V4L2_CID_LED1_MODE,
> .entity = UVC_GUID_LOGITECH_PERIPHERAL,
> .selector = 0x09,
> .size = 2,
> .offset = 8,
> .v4l2_type = V4L2_CTRL_TYPE_MENU,
> .data_type = UVC_CTRL_DATA_TYPE_UNSIGNED,
> .menu_mask = 0xF,
> .menu_mapping = { 0, 1, 2, 3 },
> .menu_names = { "Off", "On", "Blink", "Auto" },
>
> },
> {
> .id = V4L2_CID_LED1_FREQUENCY,
> .entity = UVC_GUID_LOGITECH_PERIPHERAL,
> .selector = 0x09,
> .size = 8,
> .offset = 24,
> .v4l2_type = V4L2_CTRL_TYPE_INTEGER,
> .data_type = UVC_CTRL_DATA_TYPE_UNSIGNED,
> },
>
> This script has been used to generate the mappings. They were then
> reformatted manually to follow the driver style.
>
> import sys
> import uuid
> import re
> import xml.etree.ElementTree as ET
>
> def get_namespace(root):
> return re.match(r"\{.*\}", root.tag).group(0)
>
> def get_single_guid(ns, constant):
> id = constant.find(ns + "id").text
> value = constant.find(ns + "value").text
> return (id, value)
>
> def get_constants(ns, root):
> out = dict()
> for constant in root.iter(ns + "constant"):
> attr = constant.attrib
> if attr["type"] == "integer":
> id, value = get_single_guid(ns, constant)
> if id in out:
> print(f"dupe constant {id}")
> out[id] = value
>
> return out
>
> def get_guids(ns, root):
> out = dict()
> for constant in root.iter(ns + "constant"):
> attr = constant.attrib
> if attr["type"] == "guid":
> id, value = get_single_guid(ns, constant)
> if id in out:
> print(f"dupe guid {id}")
> out[id] = value
>
> return out
>
> def get_single_control(ns, control):
> out = {}
> for id in "entity", "selector", "index", "size", "description":
> v = control.find(ns + id)
> if v is None and id == "description":
> continue
> out[id] = v.text
>
> reqs = set()
> for r in control.find(ns + "requests"):
> reqs.add(r.text)
> out["requests"] = reqs
>
> return (control.attrib["id"], out)
>
> def get_controls(ns, root):
> out = dict()
> for control in root.iter(ns + "control"):
> id, value = get_single_control(ns, control)
> if id in out:
> print(f"Dupe control id {id}")
> out[id] = value
>
> return out
>
> def get_single_mapping(ns, mapping):
> out = {}
> out["name"] = mapping.find(ns + "name").text
> uvc = mapping.find(ns + "uvc")
> for id in "size", "offset", "uvc_type":
> out[id] = uvc.find(ns + id).text
> out["control_ref"] = uvc.find(ns + "control_ref").attrib["idref"]
>
> v4l2 = mapping.find(ns + "v4l2")
> for id in "id", "v4l2_type":
> out[id] = v4l2.find(ns + id).text
>
> menu = {}
> for entry in v4l2.iter(ns + "menu_entry"):
> menu[entry.attrib["name"]] = entry.attrib["value"]
> if menu:
> out["menu"] = menu
>
> return out
>
> def get_mapping(ns, root):
> out = []
> for control in root.iter(ns + "mapping"):
> mapping = get_single_mapping(ns, control)
> out += [mapping]
>
> return out
>
> def print_guids(guids):
> for g in guids:
> print(f"#define {g} \\")
> u_bytes = uuid.UUID(guids[g]).bytes_le
> u_bytes = [f"0x{b:02x}" for b in u_bytes]
> print("\t{ " + ", ".join(u_bytes) + " }")
>
> def print_flags(flags):
> get_range = {"GET_MIN", "GET_DEF", "GET_MAX", "GET_CUR", "GET_RES"}
> if get_range.issubset(flags):
> flags -= get_range
> flags.add("GET_RANGE")
>
> flags = list(flags)
> flags.sort()
> out = ""
> for f in flags[:-1]:
> out += f"UVC_CTRL_FLAG_{f}\n\t\t\t\t| "
>
> out += f"UVC_CTRL_FLAG_{flags[-1]}"
>
> return out
>
> def print_description(desc):
> print("/*")
> for line in desc.strip().splitlines():
> print(f" * {line.strip()}")
> print("*/")
>
> def print_controls(controls, cons):
> for id in controls:
> c = controls[id]
> if "description" in c:
> print_description(c["description"])
> print(
> f"""\t{{
> \t\t.entity\t\t= {c["entity"]},
> \t\t.selector\t= {cons[c["selector"]]},
> \t\t.index\t\t= {c["index"]},
> \t\t.size\t\t= {c["size"]},
> \t\t.flags\t\t= {print_flags(c["requests"])},
> \t}},"""
> )
>
> def menu_mapping_txt(menu):
> out = f"\n\t\t.menu_mask\t= 0x{((1<<len(menu))-1):X},\n"
> out += f"\t\t.menu_mapping\t= {{ {", ".join(menu.values())} }},\n"
> out += f"\t\t.menu_names\t= {{ \"{"\", \"".join(menu.keys())}\" }},\n"
> return out
>
> def print_mappings(mappings, controls, cons):
> for m in mappings:
> c = controls[m["control_ref"]]
>
> if "menu" in m:
> menu_mapping = menu_mapping_txt(m["menu"])
> else:
> menu_mapping = ""
> print(
> f"""\t{{
> \t\t.id\t\t= {m["id"]},
> \t\t.entity\t\t= {c["entity"]},
> \t\t.selector\t= {cons[c["selector"]]},
> \t\t.size\t\t= {m["size"]},
> \t\t.offset\t\t= {m["offset"]},
> \t\t.v4l2_type\t= {m["v4l2_type"]},
> \t\t.data_type\t= {m["uvc_type"]},{menu_mapping}
> \t}},"""
> )
>
> def print_code(guids, cons, controls, mappings):
> used_controls = set()
> for m in mappings:
> used_controls.add(m["control_ref"])
>
> used_guids = set()
> for c in used_controls:
> used_guids.add(controls[c]["entity"])
>
> print("\n######GUIDs#######\n")
> print_guids({id: guids[id] for id in guids if id in used_guids})
> print("\n######CONTROLS#######\n")
> print_controls({id: controls[id] for id in controls if id in used_controls}, cons)
> print("\n######MAPPINGS#######\n")
> print_mappings(mappings, controls, cons)
> # print(guids)
> # print(used_controls)
>
> root = ET.fromstring(sys.stdin.read())
> ns = get_namespace(root)
> cons = get_constants(ns, root)
> guids = get_guids(ns, root)
> controls = get_controls(ns, root)
> mappings = get_mapping(ns, root)
> print_code(guids, cons, controls, mappings)
>
> Cc: Manav Gautama <bandwidthcrunch@...il.com>
> Cc: Martin Rubli <martin_rubli@...itech.com>
> Signed-off-by: Ricardo Ribalda <ribalda@...omium.org>
> ---
> drivers/media/usb/uvc/uvc_ctrl.c | 161 +++++++++++++++++++++++++++++++++++++++
> include/linux/usb/uvc.h | 6 ++
> 2 files changed, 167 insertions(+)
>
> diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c
> index 2905505c240c060e5034ea12d33b59d5702f2e1f..5c0398c81334649649ff654f903d03e16381a865 100644
> --- a/drivers/media/usb/uvc/uvc_ctrl.c
> +++ b/drivers/media/usb/uvc/uvc_ctrl.c
> @@ -385,6 +385,86 @@ static const struct uvc_control_info uvc_ctrls[] = {
> | UVC_CTRL_FLAG_GET_RANGE
> | UVC_CTRL_FLAG_RESTORE,
> },
> + /*
> + * Allows the control of pan/tilt motor movements for camera models
> + * that support mechanical pan/tilt.
> + *
> + * Bits 0 to 15 control pan, bits 16 to 31 control tilt.
> + * The unit of the pan/tilt values is 1/64th of a degree and the
> + * resolution is 1 degree.
> + */
> + {
> + .entity = UVC_GUID_LOGITECH_MOTOR_CONTROL_V1,
> + .selector = 1,
> + .index = 0,
> + .size = 4,
> + .flags = UVC_CTRL_FLAG_GET_DEF
> + | UVC_CTRL_FLAG_GET_MAX
> + | UVC_CTRL_FLAG_GET_MIN
> + | UVC_CTRL_FLAG_SET_CUR,
> + },
> + /*
> + * Reset the pan/tilt motors to their original position for camera
> + * models that support mechanical pan/tilt.
> + *
> + * Setting bit 0 resets the pan position.
> + * Setting bit 1 resets the tilt position.
> + *
> + * Both bits can be set at the same time to reset both, pan and tilt,
> + * at the same time.
> + */
> + {
> + .entity = UVC_GUID_LOGITECH_MOTOR_CONTROL_V1,
> + .selector = 2,
> + .index = 1,
> + .size = 1,
> + .flags = UVC_CTRL_FLAG_GET_DEF
> + | UVC_CTRL_FLAG_GET_MAX
> + | UVC_CTRL_FLAG_GET_MIN
> + | UVC_CTRL_FLAG_SET_CUR,
> + },
> + /*
> + * Allows the control of focus motor movements for camera models that
> + * support mechanical focus.
> + *
> + * Bits 0 to 7 allow selection of the desired lens position.
> + * There are no physical units, instead, the focus range is spread over
> + * 256 logical units with 0 representing infinity focus and 255 being
> + * macro focus.
> + */
> + {
> + .entity = UVC_GUID_LOGITECH_MOTOR_CONTROL_V1,
> + .selector = 3,
> + .index = 2,
> + .size = 6,
> + .flags = UVC_CTRL_FLAG_GET_CUR
> + | UVC_CTRL_FLAG_GET_DEF
> + | UVC_CTRL_FLAG_GET_MAX
> + | UVC_CTRL_FLAG_GET_MIN
> + | UVC_CTRL_FLAG_SET_CUR,
> + },
A comment would be nice here too. With that,
Reviewed-by: Laurent Pinchart <laurent.pinchart@...asonboard.com>
> + {
> + .entity = UVC_GUID_LOGITECH_PERIPHERAL,
> + .selector = 1,
> + .index = 0,
> + .size = 4,
> + .flags = UVC_CTRL_FLAG_GET_DEF
> + | UVC_CTRL_FLAG_GET_MAX
> + | UVC_CTRL_FLAG_GET_MIN
> + | UVC_CTRL_FLAG_GET_RES
> + | UVC_CTRL_FLAG_SET_CUR,
> + },
> + {
> + .entity = UVC_GUID_LOGITECH_PERIPHERAL,
> + .selector = 2,
> + .index = 1,
> + .size = 1,
> + .flags = UVC_CTRL_FLAG_GET_DEF
> + | UVC_CTRL_FLAG_GET_MAX
> + | UVC_CTRL_FLAG_GET_MIN
> + | UVC_CTRL_FLAG_GET_RES
> + | UVC_CTRL_FLAG_SET_CUR,
> + },
> };
>
> static const u32 uvc_control_classes[] = {
> @@ -1009,6 +1089,87 @@ static const struct uvc_control_mapping uvc_ctrl_mappings[] = {
> .menu_mask = BIT(V4L2_COLORFX_VIVID) |
> BIT(V4L2_COLORFX_NONE),
> },
> + {
> + .id = V4L2_CID_PAN_RELATIVE,
> + .entity = UVC_GUID_LOGITECH_MOTOR_CONTROL_V1,
> + .selector = 1,
> + .size = 16,
> + .offset = 0,
> + .v4l2_type = V4L2_CTRL_TYPE_INTEGER,
> + .data_type = UVC_CTRL_DATA_TYPE_SIGNED,
> + },
> + {
> + .id = V4L2_CID_TILT_RELATIVE,
> + .entity = UVC_GUID_LOGITECH_MOTOR_CONTROL_V1,
> + .selector = 1,
> + .size = 16,
> + .offset = 16,
> + .v4l2_type = V4L2_CTRL_TYPE_INTEGER,
> + .data_type = UVC_CTRL_DATA_TYPE_SIGNED,
> + },
> + {
> + .id = V4L2_CID_PAN_RESET,
> + .entity = UVC_GUID_LOGITECH_MOTOR_CONTROL_V1,
> + .selector = 2,
> + .size = 1,
> + .offset = 0,
> + .v4l2_type = V4L2_CTRL_TYPE_BUTTON,
> + .data_type = UVC_CTRL_DATA_TYPE_UNSIGNED,
> + },
> + {
> + .id = V4L2_CID_TILT_RESET,
> + .entity = UVC_GUID_LOGITECH_MOTOR_CONTROL_V1,
> + .selector = 2,
> + .size = 1,
> + .offset = 1,
> + .v4l2_type = V4L2_CTRL_TYPE_BUTTON,
> + .data_type = UVC_CTRL_DATA_TYPE_UNSIGNED,
> + },
> + {
> + .id = V4L2_CID_PAN_RELATIVE,
> + .entity = UVC_GUID_LOGITECH_PERIPHERAL,
> + .selector = 1,
> + .size = 16,
> + .offset = 0,
> + .v4l2_type = V4L2_CTRL_TYPE_INTEGER,
> + .data_type = UVC_CTRL_DATA_TYPE_SIGNED,
> + },
> + {
> + .id = V4L2_CID_TILT_RELATIVE,
> + .entity = UVC_GUID_LOGITECH_PERIPHERAL,
> + .selector = 1,
> + .size = 16,
> + .offset = 16,
> + .v4l2_type = V4L2_CTRL_TYPE_INTEGER,
> + .data_type = UVC_CTRL_DATA_TYPE_SIGNED,
> + },
> + {
> + .id = V4L2_CID_PAN_RESET,
> + .entity = UVC_GUID_LOGITECH_PERIPHERAL,
> + .selector = 2,
> + .size = 1,
> + .offset = 0,
> + .v4l2_type = V4L2_CTRL_TYPE_BUTTON,
> + .data_type = UVC_CTRL_DATA_TYPE_UNSIGNED,
> + },
> + {
> + .id = V4L2_CID_TILT_RESET,
> + .entity = UVC_GUID_LOGITECH_PERIPHERAL,
> + .selector = 2,
> + .size = 1,
> + .offset = 1,
> + .v4l2_type = V4L2_CTRL_TYPE_BUTTON,
> + .data_type = UVC_CTRL_DATA_TYPE_UNSIGNED,
> + },
> + {
> + .id = V4L2_CID_FOCUS_ABSOLUTE,
> + .entity = UVC_GUID_LOGITECH_MOTOR_CONTROL_V1,
> + .selector = 3,
> + .size = 8,
> + .offset = 0,
> + .v4l2_type = V4L2_CTRL_TYPE_INTEGER,
> + .data_type = UVC_CTRL_DATA_TYPE_UNSIGNED,
> + },
> };
>
> /* ------------------------------------------------------------------------
> diff --git a/include/linux/usb/uvc.h b/include/linux/usb/uvc.h
> index 22e0dab0809e296e089940620ae0e8838e109701..b939a01da11466747249c64c72a3ea40cd364a59 100644
> --- a/include/linux/usb/uvc.h
> +++ b/include/linux/usb/uvc.h
> @@ -35,6 +35,12 @@
> #define UVC_GUID_MSXU_1_5 \
> {0xdc, 0x95, 0x3f, 0x0f, 0x32, 0x26, 0x4e, 0x4c, \
> 0x92, 0xc9, 0xa0, 0x47, 0x82, 0xf4, 0x3b, 0xc8}
> +#define UVC_GUID_LOGITECH_MOTOR_CONTROL_V1 \
> + {0x82, 0x06, 0x61, 0x63, 0x70, 0x50, 0xab, 0x49, \
> + 0xb8, 0xcc, 0xb3, 0x85, 0x5e, 0x8d, 0x22, 0x56 }
> +#define UVC_GUID_LOGITECH_PERIPHERAL \
> + {0x21, 0x2d, 0xe5, 0xff, 0x30, 0x80, 0x2c, 0x4e, \
> + 0x82, 0xd9, 0xf5, 0x87, 0xd0, 0x05, 0x40, 0xbd }
>
> /* https://learn.microsoft.com/en-us/windows-hardware/drivers/stream/uvc-extensions-1-5#222-extension-unit-controls */
> #define UVC_MSXU_CONTROL_FOCUS 0x01
--
Regards,
Laurent Pinchart
Powered by blists - more mailing lists