[PATCH v2 6/7] media: uvcvideo: Implement mask for V4L2_CTRL_TYPE_MENU

From: Ricardo Ribalda
Date: Wed Sep 21 2022 - 05:13:07 EST


Replace the count with a mask field that lets us choose not only the max
value, but also the minimum value and what values are valid in between.

Signed-off-by: Ricardo Ribalda <ribalda@xxxxxxxxxxxx>
Suggested-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>

diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c
index 526572044e82..df273b829961 100644
--- a/drivers/media/usb/uvc/uvc_ctrl.c
+++ b/drivers/media/usb/uvc/uvc_ctrl.c
@@ -6,6 +6,7 @@
* Laurent Pinchart (laurent.pinchart@xxxxxxxxxxxxxxxx)
*/

+#include <linux/bitops.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/module.h>
@@ -524,7 +525,7 @@ static const struct uvc_control_mapping uvc_ctrl_mappings[] = {
.v4l2_type = V4L2_CTRL_TYPE_MENU,
.data_type = UVC_CTRL_DATA_TYPE_BITMASK,
.menu_info = exposure_auto_controls,
- .menu_count = ARRAY_SIZE(exposure_auto_controls),
+ .menu_mask = BIT_MASK(ARRAY_SIZE(exposure_auto_controls)),
.slave_ids = { V4L2_CID_EXPOSURE_ABSOLUTE, },
},
{
@@ -730,7 +731,7 @@ static const struct uvc_control_mapping uvc_ctrl_mappings_uvc11[] = {
.v4l2_type = V4L2_CTRL_TYPE_MENU,
.data_type = UVC_CTRL_DATA_TYPE_ENUM,
.menu_info = power_line_frequency_controls,
- .menu_count = ARRAY_SIZE(power_line_frequency_controls) - 1,
+ .menu_mask = BIT_MASK(ARRAY_SIZE(power_line_frequency_controls) - 1),
},
};

@@ -744,7 +745,7 @@ static const struct uvc_control_mapping uvc_ctrl_mappings_uvc15[] = {
.v4l2_type = V4L2_CTRL_TYPE_MENU,
.data_type = UVC_CTRL_DATA_TYPE_ENUM,
.menu_info = power_line_frequency_controls,
- .menu_count = ARRAY_SIZE(power_line_frequency_controls),
+ .menu_mask = BIT_MASK(ARRAY_SIZE(power_line_frequency_controls)),
},
};

@@ -974,7 +975,9 @@ static s32 __uvc_ctrl_get_value(struct uvc_control_mapping *mapping,
const struct uvc_menu_info *menu = mapping->menu_info;
unsigned int i;

- for (i = 0; i < mapping->menu_count; ++i, ++menu) {
+ for (i = 0; BIT(i) <= mapping->menu_mask; ++i, ++menu) {
+ if (!test_bit(i, &mapping->menu_mask))
+ continue;
if (menu->value == value) {
value = i;
break;
@@ -1212,12 +1215,14 @@ static int __uvc_query_v4l2_ctrl(struct uvc_video_chain *chain,

switch (mapping->v4l2_type) {
case V4L2_CTRL_TYPE_MENU:
- v4l2_ctrl->minimum = 0;
- v4l2_ctrl->maximum = mapping->menu_count - 1;
+ v4l2_ctrl->minimum = ffs(mapping->menu_mask) - 1;
+ v4l2_ctrl->maximum = fls(mapping->menu_mask) - 1;
v4l2_ctrl->step = 1;

menu = mapping->menu_info;
- for (i = 0; i < mapping->menu_count; ++i, ++menu) {
+ for (i = 0; BIT(i) <= mapping->menu_mask; ++i, ++menu) {
+ if (!test_bit(i, &mapping->menu_mask))
+ continue;
if (menu->value == v4l2_ctrl->default_value) {
v4l2_ctrl->default_value = i;
break;
@@ -1338,7 +1343,7 @@ int uvc_query_v4l2_menu(struct uvc_video_chain *chain,
goto done;
}

- if (query_menu->index >= mapping->menu_count) {
+ if (!test_bit(query_menu->index, &mapping->menu_mask)) {
ret = -EINVAL;
goto done;
}
@@ -1853,8 +1858,13 @@ int uvc_ctrl_set(struct uvc_fh *handle,
break;

case V4L2_CTRL_TYPE_MENU:
- if (xctrl->value < 0 || xctrl->value >= mapping->menu_count)
+ if (xctrl->value < (ffs(mapping->menu_mask) - 1) ||
+ xctrl->value > (fls(mapping->menu_mask) - 1))
return -ERANGE;
+
+ if (!test_bit(xctrl->value, &mapping->menu_mask))
+ return -EINVAL;
+
value = mapping->menu_info[xctrl->value].value;

/*
@@ -2301,7 +2311,7 @@ static int __uvc_ctrl_add_mapping(struct uvc_video_chain *chain,

INIT_LIST_HEAD(&map->ev_subs);

- size = sizeof(*mapping->menu_info) * mapping->menu_count;
+ size = sizeof(*mapping->menu_info) * fls(mapping->menu_mask);
map->menu_info = kmemdup(mapping->menu_info, size, GFP_KERNEL);
if (map->menu_info == NULL) {
kfree(map->name);
diff --git a/drivers/media/usb/uvc/uvc_driver.c b/drivers/media/usb/uvc/uvc_driver.c
index 9c05776f11d1..abdb9ca7eed6 100644
--- a/drivers/media/usb/uvc/uvc_driver.c
+++ b/drivers/media/usb/uvc/uvc_driver.c
@@ -2675,7 +2675,7 @@ static const struct uvc_control_mapping uvc_ctrl_power_line_mapping_limited = {
.v4l2_type = V4L2_CTRL_TYPE_MENU,
.data_type = UVC_CTRL_DATA_TYPE_ENUM,
.menu_info = power_line_frequency_controls_limited,
- .menu_count = ARRAY_SIZE(power_line_frequency_controls_limited),
+ .menu_mask = BIT_MASK(ARRAY_SIZE(power_line_frequency_controls_limited)),
};

static const struct uvc_device_info uvc_ctrl_power_line_limited = {
diff --git a/drivers/media/usb/uvc/uvc_v4l2.c b/drivers/media/usb/uvc/uvc_v4l2.c
index d95168cdc2d1..e6792fd46bf5 100644
--- a/drivers/media/usb/uvc/uvc_v4l2.c
+++ b/drivers/media/usb/uvc/uvc_v4l2.c
@@ -80,7 +80,7 @@ static int uvc_ioctl_ctrl_map(struct uvc_video_chain *chain,
goto free_map;
}

- map->menu_count = xmap->menu_count;
+ map->menu_mask = BIT_MASK(xmap->menu_count);
break;

default:
diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h
index 644d5fcf2eef..7e2339fc256e 100644
--- a/drivers/media/usb/uvc/uvcvideo.h
+++ b/drivers/media/usb/uvc/uvcvideo.h
@@ -255,7 +255,7 @@ struct uvc_control_mapping {
u32 data_type;

const struct uvc_menu_info *menu_info;
- u32 menu_count;
+ unsigned long menu_mask;

u32 master_id;
s32 master_manual;

--
b4 0.11.0-dev-d93f8