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author | Martin Rubli <martin_rubli@logitech.com> | 2010-10-02 19:10:16 -0300 |
---|---|---|
committer | Mauro Carvalho Chehab <mchehab@redhat.com> | 2011-05-20 09:30:26 -0300 |
commit | fe78d187fe792fac5d190b19a2806c23df28891e (patch) | |
tree | dafe6b4217b6a731b8f107df9694c2dcc58071fe /drivers/media/video/uvc/uvc_ctrl.c | |
parent | 837d50b5648347b1a011f42e474eeb5f671cc259 (diff) | |
download | lwn-fe78d187fe792fac5d190b19a2806c23df28891e.tar.gz lwn-fe78d187fe792fac5d190b19a2806c23df28891e.zip |
[media] uvcvideo: Add UVCIOC_CTRL_QUERY ioctl
This ioctl extends UVCIOC_CTRL_GET/SET by not only allowing to get/set
XU controls but to also send arbitrary UVC commands to XU controls,
namely GET_CUR, SET_CUR, GET_MIN, GET_MAX, GET_RES, GET_LEN, GET_INFO
and GET_DEF. This is required for applications to work with XU controls,
so that they can properly query the size and allocate the necessary
buffers.
Signed-off-by: Martin Rubli <martin_rubli@logitech.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Diffstat (limited to 'drivers/media/video/uvc/uvc_ctrl.c')
-rw-r--r-- | drivers/media/video/uvc/uvc_ctrl.c | 92 |
1 files changed, 61 insertions, 31 deletions
diff --git a/drivers/media/video/uvc/uvc_ctrl.c b/drivers/media/video/uvc/uvc_ctrl.c index 59f8a9ad3796..47175ccd2f01 100644 --- a/drivers/media/video/uvc/uvc_ctrl.c +++ b/drivers/media/video/uvc/uvc_ctrl.c @@ -1344,32 +1344,33 @@ static int uvc_ctrl_init_xu_ctrl(struct uvc_device *dev, } int uvc_xu_ctrl_query(struct uvc_video_chain *chain, - struct uvc_xu_control *xctrl, int set) + struct uvc_xu_control_query *xqry) { struct uvc_entity *entity; - struct uvc_control *ctrl = NULL; + struct uvc_control *ctrl; unsigned int i, found = 0; - int restore = 0; - __u8 *data; + __u32 reqflags; + __u16 size; + __u8 *data = NULL; int ret; /* Find the extension unit. */ list_for_each_entry(entity, &chain->entities, chain) { if (UVC_ENTITY_TYPE(entity) == UVC_VC_EXTENSION_UNIT && - entity->id == xctrl->unit) + entity->id == xqry->unit) break; } - if (entity->id != xctrl->unit) { + if (entity->id != xqry->unit) { uvc_trace(UVC_TRACE_CONTROL, "Extension unit %u not found.\n", - xctrl->unit); - return -EINVAL; + xqry->unit); + return -ENOENT; } /* Find the control and perform delayed initialization if needed. */ for (i = 0; i < entity->ncontrols; ++i) { ctrl = &entity->controls[i]; - if (ctrl->index == xctrl->selector - 1) { + if (ctrl->index == xqry->selector - 1) { found = 1; break; } @@ -1377,8 +1378,8 @@ int uvc_xu_ctrl_query(struct uvc_video_chain *chain, if (!found) { uvc_trace(UVC_TRACE_CONTROL, "Control %pUl/%u not found.\n", - entity->extension.guidExtensionCode, xctrl->selector); - return -EINVAL; + entity->extension.guidExtensionCode, xqry->selector); + return -ENOENT; } if (mutex_lock_interruptible(&chain->ctrl_mutex)) @@ -1390,43 +1391,72 @@ int uvc_xu_ctrl_query(struct uvc_video_chain *chain, goto done; } - /* Validate control data size. */ - if (ctrl->info.size != xctrl->size) { + /* Validate the required buffer size and flags for the request */ + reqflags = 0; + size = ctrl->info.size; + + switch (xqry->query) { + case UVC_GET_CUR: + reqflags = UVC_CONTROL_GET_CUR; + break; + case UVC_GET_MIN: + reqflags = UVC_CONTROL_GET_MIN; + break; + case UVC_GET_MAX: + reqflags = UVC_CONTROL_GET_MAX; + break; + case UVC_GET_DEF: + reqflags = UVC_CONTROL_GET_DEF; + break; + case UVC_GET_RES: + reqflags = UVC_CONTROL_GET_RES; + break; + case UVC_SET_CUR: + reqflags = UVC_CONTROL_SET_CUR; + break; + case UVC_GET_LEN: + size = 2; + break; + case UVC_GET_INFO: + size = 1; + break; + default: ret = -EINVAL; goto done; } - if ((set && !(ctrl->info.flags & UVC_CONTROL_SET_CUR)) || - (!set && !(ctrl->info.flags & UVC_CONTROL_GET_CUR))) { - ret = -EINVAL; + if (size != xqry->size) { + ret = -ENOBUFS; goto done; } - memcpy(uvc_ctrl_data(ctrl, UVC_CTRL_DATA_BACKUP), - uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT), - ctrl->info.size); - data = uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT); - restore = set; + if (reqflags && !(ctrl->info.flags & reqflags)) { + ret = -EBADRQC; + goto done; + } - if (set && copy_from_user(data, xctrl->data, xctrl->size)) { + data = kmalloc(size, GFP_KERNEL); + if (data == NULL) { + ret = -ENOMEM; + goto done; + } + + if (xqry->query == UVC_SET_CUR && + copy_from_user(data, xqry->data, size)) { ret = -EFAULT; goto done; } - ret = uvc_query_ctrl(chain->dev, set ? UVC_SET_CUR : UVC_GET_CUR, - xctrl->unit, chain->dev->intfnum, xctrl->selector, - data, xctrl->size); + ret = uvc_query_ctrl(chain->dev, xqry->query, xqry->unit, + chain->dev->intfnum, xqry->selector, data, size); if (ret < 0) goto done; - if (!set && copy_to_user(xctrl->data, data, xctrl->size)) + if (xqry->query != UVC_SET_CUR && + copy_to_user(xqry->data, data, size)) ret = -EFAULT; done: - if (ret && restore) - memcpy(uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT), - uvc_ctrl_data(ctrl, UVC_CTRL_DATA_BACKUP), - xctrl->size); - + kfree(data); mutex_unlock(&chain->ctrl_mutex); return ret; } |