From: Daniel Scally <dan.scally@ideasonboard.com>
To: linux-usb@vger.kernel.org, gregkh@linuxfoundation.org,
laurent.pinchart@ideasonboard.com
Cc: mgr@pengutronix.de, balbi@kernel.org,
kieran.bingham@ideasonboard.com, torleiv@huddly.com,
stern@rowland.harvard.edu,
Daniel Scally <dan.scally@ideasonboard.com>
Subject: [PATCH v3 08/11] usb: gadget: uvc: Allow linking XUs to string descriptors
Date: Mon, 30 Jan 2023 09:34:40 +0000 [thread overview]
Message-ID: <20230130093443.25644-9-dan.scally@ideasonboard.com> (raw)
In-Reply-To: <20230130093443.25644-1-dan.scally@ideasonboard.com>
Add .allow_link() and .drop_link() callbacks to allow users to link
an extension unit descriptor to a string descriptor.
Signed-off-by: Daniel Scally <dan.scally@ideasonboard.com>
---
Changes in v3:
- Changed the target of the links to in <gadget root>/strings
Changes in v2:
- New patch
drivers/usb/gadget/function/uvc_configfs.c | 52 ++++++++++++++++++++++
drivers/usb/gadget/function/uvc_configfs.h | 1 +
2 files changed, 53 insertions(+)
diff --git a/drivers/usb/gadget/function/uvc_configfs.c b/drivers/usb/gadget/function/uvc_configfs.c
index a81613e9652d..9da3b784f954 100644
--- a/drivers/usb/gadget/function/uvc_configfs.c
+++ b/drivers/usb/gadget/function/uvc_configfs.c
@@ -1063,8 +1063,60 @@ static void uvcg_extension_release(struct config_item *item)
kfree(xu);
}
+static int uvcg_extension_allow_link(struct config_item *src, struct config_item *tgt)
+{
+ struct mutex *su_mutex = &src->ci_group->cg_subsys->su_mutex;
+ struct uvcg_extension *xu = to_uvcg_extension(src);
+ struct config_item *gadget_item;
+ struct gadget_string *string;
+ struct config_item *strings;
+ int ret = 0;
+
+ mutex_lock(su_mutex); /* for navigating configfs hierarchy */
+
+ /* Validate that the target of the link is an entry in strings/<langid> */
+ gadget_item = src->ci_parent->ci_parent->ci_parent->ci_parent->ci_parent;
+ strings = config_group_find_item(to_config_group(gadget_item), "strings");
+ if (!strings || tgt->ci_parent->ci_parent != strings) {
+ ret = -EINVAL;
+ goto put_strings;
+ }
+
+ string = to_gadget_string(tgt);
+ xu->string_descriptor_index = string->usb_string.id;
+
+put_strings:
+ config_item_put(strings);
+ mutex_unlock(su_mutex);
+
+ return ret;
+}
+
+static void uvcg_extension_drop_link(struct config_item *src, struct config_item *tgt)
+{
+ struct mutex *su_mutex = &src->ci_group->cg_subsys->su_mutex;
+ struct uvcg_extension *xu = to_uvcg_extension(src);
+ struct config_item *opts_item;
+ struct f_uvc_opts *opts;
+
+ mutex_lock(su_mutex); /* for navigating configfs hierarchy */
+
+ opts_item = src->ci_parent->ci_parent->ci_parent;
+ opts = to_f_uvc_opts(opts_item);
+
+ mutex_lock(&opts->lock);
+
+ xu->string_descriptor_index = 0;
+
+ mutex_unlock(&opts->lock);
+
+ mutex_unlock(su_mutex);
+}
+
static struct configfs_item_operations uvcg_extension_item_ops = {
.release = uvcg_extension_release,
+ .allow_link = uvcg_extension_allow_link,
+ .drop_link = uvcg_extension_drop_link,
};
static const struct config_item_type uvcg_extension_type = {
diff --git a/drivers/usb/gadget/function/uvc_configfs.h b/drivers/usb/gadget/function/uvc_configfs.h
index c9a4182fb26f..bf188080034c 100644
--- a/drivers/usb/gadget/function/uvc_configfs.h
+++ b/drivers/usb/gadget/function/uvc_configfs.h
@@ -153,6 +153,7 @@ struct uvcg_extension_unit_descriptor {
struct uvcg_extension {
struct config_item item;
struct list_head list;
+ u8 string_descriptor_index;
struct uvcg_extension_unit_descriptor desc;
};
--
2.34.1
next prev parent reply other threads:[~2023-01-30 9:38 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-01-30 9:34 [PATCH v3 00/11] Add XU support to UVC Gadget Daniel Scally
2023-01-30 9:34 ` [PATCH v3 01/11] usb: gadget: uvc: Make bSourceID read/write Daniel Scally
2023-01-30 9:34 ` [PATCH v3 02/11] usb: gadget: uvc: Generalise helper functions for reuse Daniel Scally
2023-01-30 9:34 ` [PATCH v3 03/11] usb: gadget: uvc: Allow definition of XUs in configfs Daniel Scally
2023-01-30 20:13 ` kernel test robot
2023-01-30 9:34 ` [PATCH v3 04/11] usb: gadget: uvc: Copy XU descriptors during .bind() Daniel Scally
2023-01-30 9:34 ` [PATCH v3 05/11] usb: gadget: configfs: Rename struct gadget_strings Daniel Scally
2023-01-30 9:34 ` [PATCH v3 06/11] usb: gadget: configfs: Support arbitrary string descriptors Daniel Scally
2023-01-30 14:24 ` kernel test robot
2023-01-30 16:07 ` kernel test robot
2023-01-30 16:37 ` Alan Stern
2023-02-02 13:06 ` Dan Scally
2023-01-30 9:34 ` [PATCH v3 07/11] usb: gadget: configfs: Attach arbitrary strings to cdev Daniel Scally
2023-01-31 7:35 ` Dan Carpenter
2023-02-01 9:50 ` Dan Scally
2023-01-30 9:34 ` Daniel Scally [this message]
2023-01-30 9:34 ` [PATCH v3 09/11] usb: gadget: uvc: Pick up custom string descriptor IDs Daniel Scally
2023-01-30 9:34 ` [PATCH v3 10/11] usb: gadget: uvc: Allow linking function to string descs Daniel Scally
2023-01-30 9:34 ` [PATCH v3 11/11] usb: gadget: uvc: Use custom strings if available Daniel Scally
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