[PATCH 3/6] media: uvcvideo: Implement mask for V4L2_CTRL_TYPE_MENU

From: Ricardo Ribalda
Date: Thu Jan 05 2023 - 07:33:50 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.

Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
Signed-off-by: Ricardo Ribalda <ribalda@xxxxxxxxxxxx>
Suggested-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
---
drivers/media/usb/uvc/uvc_ctrl.c | 33 +++++++++++++++++++++++----------
drivers/media/usb/uvc/uvc_driver.c | 4 +++-
drivers/media/usb/uvc/uvc_v4l2.c | 3 ++-
drivers/media/usb/uvc/uvcvideo.h | 2 +-
4 files changed, 29 insertions(+), 13 deletions(-)

diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c
index ffa0e2654264..2ebe5cc18ad9 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>
@@ -525,7 +526,8 @@ 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 =
+ GENMASK(ARRAY_SIZE(exposure_auto_controls) - 1, 0),
.slave_ids = { V4L2_CID_EXPOSURE_ABSOLUTE, },
},
{
@@ -731,7 +733,8 @@ 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 = GENMASK(V4L2_CID_POWER_LINE_FREQUENCY_60HZ,
+ V4L2_CID_POWER_LINE_FREQUENCY_DISABLED),
},
};

@@ -745,7 +748,8 @@ 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 = GENMASK(V4L2_CID_POWER_LINE_FREQUENCY_AUTO,
+ V4L2_CID_POWER_LINE_FREQUENCY_DISABLED),
},
};

@@ -975,7 +979,9 @@ 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;
@@ -1228,12 +1234,14 @@ 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;
@@ -1354,7 +1362,7 @@ 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;
}
@@ -1868,8 +1876,13 @@ 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;

/*
@@ -2306,7 +2319,7 @@ 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)
goto err_nomem;
diff --git a/drivers/media/usb/uvc/uvc_driver.c b/drivers/media/usb/uvc/uvc_driver.c
index 6d08457ecb9c..e659670ea2d8 100644
--- a/drivers/media/usb/uvc/uvc_driver.c
+++ b/drivers/media/usb/uvc/uvc_driver.c
@@ -7,6 +7,7 @@
*/

#include <linux/atomic.h>
+#include <linux/bits.h>
#include <linux/gpio/consumer.h>
#include <linux/kernel.h>
#include <linux/list.h>
@@ -2391,7 +2392,8 @@ 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 =
+ GENMASK(ARRAY_SIZE(power_line_frequency_controls_limited) - 1, 0),
};

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 3edb54c086b2..0774a11360c0 100644
--- a/drivers/media/usb/uvc/uvc_v4l2.c
+++ b/drivers/media/usb/uvc/uvc_v4l2.c
@@ -6,6 +6,7 @@
* Laurent Pinchart (laurent.pinchart@xxxxxxxxxxxxxxxx)
*/

+#include <linux/bits.h>
#include <linux/compat.h>
#include <linux/kernel.h>
#include <linux/list.h>
@@ -80,7 +81,7 @@ static int uvc_ioctl_ctrl_map(struct uvc_video_chain *chain,
goto free_map;
}

- map->menu_count = xmap->menu_count;
+ map->menu_mask = GENMASK(xmap->menu_count - 1, 0);
break;

default:
diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h
index 41ba0bbd8171..a8eec43cd860 100644
--- a/drivers/media/usb/uvc/uvcvideo.h
+++ b/drivers/media/usb/uvc/uvcvideo.h
@@ -115,7 +115,7 @@ 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;

--
2.39.0.314.g84b9a713c41-goog-b4-0.11.0-dev-696ae