usb: gadget: uvc: Make bSourceID read/write

[ Upstream commit b3c839bd8a ]

At the moment, the UVC function graph is hardcoded IT -> PU -> OT.
To add XU support we need the ability to insert the XU descriptors
into the chain. To facilitate that, make the output terminal's
bSourceID attribute writeable so that we can configure its source.

Signed-off-by: Daniel Scally <dan.scally@ideasonboard.com>
Link: https://lore.kernel.org/r/20230206161802.892954-2-dan.scally@ideasonboard.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Daniel Scally 2023-02-06 16:17:52 +00:00 committed by Greg Kroah-Hartman
parent 00b42e3b20
commit ec8a0f412c
2 changed files with 59 additions and 2 deletions

View File

@ -52,7 +52,7 @@ Date: Dec 2014
KernelVersion: 4.0
Description: Default output terminal descriptors
All attributes read only:
All attributes read only except bSourceID:
============== =============================================
iTerminal index of string descriptor

View File

@ -483,11 +483,68 @@ UVC_ATTR_RO(uvcg_default_output_, cname, aname)
UVCG_DEFAULT_OUTPUT_ATTR(b_terminal_id, bTerminalID, 8);
UVCG_DEFAULT_OUTPUT_ATTR(w_terminal_type, wTerminalType, 16);
UVCG_DEFAULT_OUTPUT_ATTR(b_assoc_terminal, bAssocTerminal, 8);
UVCG_DEFAULT_OUTPUT_ATTR(b_source_id, bSourceID, 8);
UVCG_DEFAULT_OUTPUT_ATTR(i_terminal, iTerminal, 8);
#undef UVCG_DEFAULT_OUTPUT_ATTR
static ssize_t uvcg_default_output_b_source_id_show(struct config_item *item,
char *page)
{
struct config_group *group = to_config_group(item);
struct f_uvc_opts *opts;
struct config_item *opts_item;
struct mutex *su_mutex = &group->cg_subsys->su_mutex;
struct uvc_output_terminal_descriptor *cd;
int result;
mutex_lock(su_mutex); /* for navigating configfs hierarchy */
opts_item = group->cg_item.ci_parent->ci_parent->
ci_parent->ci_parent;
opts = to_f_uvc_opts(opts_item);
cd = &opts->uvc_output_terminal;
mutex_lock(&opts->lock);
result = sprintf(page, "%u\n", le8_to_cpu(cd->bSourceID));
mutex_unlock(&opts->lock);
mutex_unlock(su_mutex);
return result;
}
static ssize_t uvcg_default_output_b_source_id_store(struct config_item *item,
const char *page, size_t len)
{
struct config_group *group = to_config_group(item);
struct f_uvc_opts *opts;
struct config_item *opts_item;
struct mutex *su_mutex = &group->cg_subsys->su_mutex;
struct uvc_output_terminal_descriptor *cd;
int result;
u8 num;
mutex_lock(su_mutex); /* for navigating configfs hierarchy */
opts_item = group->cg_item.ci_parent->ci_parent->
ci_parent->ci_parent;
opts = to_f_uvc_opts(opts_item);
cd = &opts->uvc_output_terminal;
result = kstrtou8(page, 0, &num);
if (result)
return result;
mutex_lock(&opts->lock);
cd->bSourceID = num;
mutex_unlock(&opts->lock);
mutex_unlock(su_mutex);
return len;
}
UVC_ATTR(uvcg_default_output_, b_source_id, bSourceID);
static struct configfs_attribute *uvcg_default_output_attrs[] = {
&uvcg_default_output_attr_b_terminal_id,
&uvcg_default_output_attr_w_terminal_type,