On Sun, Jan 01, 2023 at 12:40:12PM +0100, Jó Ágila Bitsch wrote:
> There is a custom (non-USB IF) extension to the USB standard:
>
> https://wicg.github.io/webusb/
>
> This specification is published under the W3C Community Contributor
> Agreement, which in particular allows to implement the specification
> without any royalties.
>
> The specification allows USB gadgets to announce an URL to landing
> page and describes a Javascript interface for websites to interact
> with the USB gadget, if the user allows it. It is currently
> supported by Chromium-based browsers, such as Chrome, Edge and
> Opera on all major operating systems including Linux.
>
> This patch adds optional support for Linux-based USB gadgets
> wishing to expose such a landing page.
>
> During device enumeration, a host recognizes that the announced
> USB version is at least 2.01, which means, that there are BOS
> descriptors available. The device than announces WebUSB support
> using a platform device capability. This includes a vendor code
> under which the landing page URL can be retrieved using a
> vendor-specific request.
>
> Usage is modeled after os_desc descriptors:
> echo 1 > webusb/use
> echo "https://www.kernel.org" > webusb/landingPage
>
> lsusb will report the device with the following lines:
> Platform Device Capability:
> bLength 24
> bDescriptorType 16
> bDevCapabilityType 5
> bReserved 0
> PlatformCapabilityUUID {3408b638-09a9-47a0-8bfd-a0768815b665}
> WebUSB:
> bcdVersion 1.00
> bVendorCode 0
> iLandingPage 1 https://www.kernel.org
>
> Signed-off-by: Jó Ágila Bitsch <jgilab@gmail.com>
> ---
> Documentation/ABI/testing/configfs-usb-gadget | 13 ++
> drivers/usb/gadget/composite.c | 96 ++++++++++--
> drivers/usb/gadget/configfs.c | 145 ++++++++++++++++++
> include/linux/usb/composite.h | 6 +
> include/uapi/linux/usb/ch9.h | 33 ++++
> 5 files changed, 283 insertions(+), 10 deletions(-)
>
Hi,
This is the friendly patch-bot of Greg Kroah-Hartman. You have sent him
a patch that has triggered this response. He used to manually respond
to these common problems, but in order to save his sanity (he kept
writing the same thing over and over, yet to different people), I was
created. Hopefully you will not take offence and will fix the problem
in your patch and resubmit it so that it can be accepted into the Linux
kernel tree.
You are receiving this message because of the following common error(s)
as indicated below:
- This looks like a new version of a previously submitted patch, but you
did not list below the --- line any changes from the previous version.
Please read the section entitled "The canonical patch format" in the
kernel file, Documentation/process/submitting-patches.rst for what
needs to be done here to properly describe this.
If you wish to discuss this problem further, or you have questions about
how to resolve this issue, please feel free to respond to this email and
Greg will reply once he has dug out from the pending patches received
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thanks,
greg k-h's patch email bot
@@ -143,3 +143,16 @@ Description:
qw_sign an identifier to be reported as "OS String"
proper
============= ===============================================
+
+What: /config/usb-gadget/gadget/webusb
+Date: Dec 2022
+KernelVersion: 6.2
+Description:
+ This group contains "WebUSB" extension handling attributes.
+
+ ============= ===============================================
+ use flag turning "WebUSB" support on/off
+ bcdVersion bcd WebUSB specification version number
+ b_vendor_code one-byte value used for custom per-device
+ landing_page UTF-8 encoded URL of the device's landing page
+ ============= ===============================================
@@ -14,6 +14,7 @@
#include <linux/device.h>
#include <linux/utsname.h>
#include <linux/bitfield.h>
+#include <linux/uuid.h>
#include <linux/usb/composite.h>
#include <linux/usb/otg.h>
@@ -713,14 +714,16 @@ static int bos_desc(struct usb_composite_dev *cdev)
* A SuperSpeed device shall include the USB2.0 extension descriptor
* and shall support LPM when operating in USB2.0 HS mode.
*/
- usb_ext = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
- bos->bNumDeviceCaps++;
- le16_add_cpu(&bos->wTotalLength, USB_DT_USB_EXT_CAP_SIZE);
- usb_ext->bLength = USB_DT_USB_EXT_CAP_SIZE;
- usb_ext->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
- usb_ext->bDevCapabilityType = USB_CAP_TYPE_EXT;
- usb_ext->bmAttributes = cpu_to_le32(USB_LPM_SUPPORT |
- USB_BESL_SUPPORT | besl);
+ if (cdev->gadget->lpm_capable) {
+ usb_ext = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
+ bos->bNumDeviceCaps++;
+ le16_add_cpu(&bos->wTotalLength, USB_DT_USB_EXT_CAP_SIZE);
+ usb_ext->bLength = USB_DT_USB_EXT_CAP_SIZE;
+ usb_ext->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
+ usb_ext->bDevCapabilityType = USB_CAP_TYPE_EXT;
+ usb_ext->bmAttributes = cpu_to_le32(USB_LPM_SUPPORT |
+ USB_BESL_SUPPORT | besl);
+ }
/*
* The Superspeed USB Capability descriptor shall be implemented by all
@@ -821,6 +824,40 @@ static int bos_desc(struct usb_composite_dev *cdev)
}
}
+ /*
+ * Following the specifaction at:
+ * https://wicg.github.io/webusb/#webusb-platform-capability-descriptor
+ */
+ if (cdev->use_webusb) {
+ struct usb_webusb_cap_descriptor *webusb_cap;
+ /*
+ * little endian PlatformCapablityUUID for WebUSB:
+ * 3408b638-09a9-47a0-8bfd-a0768815b665
+ */
+ uuid_t webusb_uuid = UUID_INIT(0x38b60834, 0xa909, 0xa047, 0x8b, 0xfd, 0xa0, 0x76,
+ 0x88, 0x15, 0xb6, 0x65);
+
+ webusb_cap = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
+ bos->bNumDeviceCaps++;
+
+ le16_add_cpu(&bos->wTotalLength, USB_DT_WEBUSB_SIZE);
+ webusb_cap->bLength = USB_DT_WEBUSB_SIZE;
+ webusb_cap->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
+ webusb_cap->bDevCapabilityType = USB_PLAT_DEV_CAP_TYPE;
+ webusb_cap->bReserved = 0;
+ export_uuid(webusb_cap->UUID, &webusb_uuid);
+ if (cdev->bcd_webusb_version != 0)
+ webusb_cap->bcdVersion = cpu_to_le16(cdev->bcd_webusb_version);
+ else
+ webusb_cap->bcdVersion = cpu_to_le16(0x0100);
+
+ webusb_cap->bVendorCode = cdev->b_webusb_vendor_code;
+ if (strnlen(cdev->landing_page, sizeof(cdev->landing_page)) > 0)
+ webusb_cap->iLandingPage = 1;
+ else
+ webusb_cap->iLandingPage = 0;
+ }
+
return le16_to_cpu(bos->wTotalLength);
}
@@ -1744,7 +1781,7 @@ composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
cdev->desc.bcdUSB = cpu_to_le16(0x0210);
}
} else {
- if (gadget->lpm_capable)
+ if (gadget->lpm_capable || cdev->use_webusb)
cdev->desc.bcdUSB = cpu_to_le16(0x0201);
else
cdev->desc.bcdUSB = cpu_to_le16(0x0200);
@@ -1779,7 +1816,7 @@ composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
break;
case USB_DT_BOS:
if (gadget_is_superspeed(gadget) ||
- gadget->lpm_capable) {
+ gadget->lpm_capable || cdev->use_webusb) {
value = bos_desc(cdev);
value = min(w_length, (u16) value);
}
@@ -2013,6 +2050,45 @@ composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
goto check_value;
}
+ /*
+ * webusb descriptor handling, following:
+ * https://wicg.github.io/webusb/#device-requests
+ */
+ if (cdev->use_webusb &&
+ (ctrl->bRequestType & USB_TYPE_VENDOR) &&
+ ctrl->wIndex == /* WEBUSB_GET_URL*/ 2 &&
+ ctrl->bRequest == cdev->b_webusb_vendor_code) {
+ /*
+ * specification of the url descriptor in WebUSB:
+ * https://wicg.github.io/webusb/#webusb-descriptors
+ */
+ u8 *buf;
+ unsigned int landing_page_length;
+
+ buf = cdev->req->buf;
+ #define WEBUSB_URL 3
+ buf[1] = WEBUSB_URL;
+
+ landing_page_length = strnlen(cdev->landing_page, 252);
+ if (strncasecmp("https://", cdev->landing_page, 8) == 0) {
+ buf[2] = 0x01;
+ memcpy(buf+3, cdev->landing_page+8, landing_page_length-8);
+ buf[0] = landing_page_length - 8 + 3;
+ } else if (strncasecmp("http://", cdev->landing_page, 7) == 0) {
+ buf[2] = 0x00;
+ memcpy(buf+3, cdev->landing_page+7, landing_page_length-7);
+ buf[0] = landing_page_length - 7 + 3;
+ } else {
+ buf[2] = 0xFF;
+ memcpy(buf+3, cdev->landing_page, landing_page_length);
+ buf[0] = landing_page_length + 3;
+ }
+
+ value = buf[0];
+
+ goto check_value;
+ }
+
VDBG(cdev,
"non-core control req%02x.%02x v%04x i%04x l%d\n",
ctrl->bRequestType, ctrl->bRequest,
@@ -39,6 +39,7 @@ struct gadget_info {
struct config_group configs_group;
struct config_group strings_group;
struct config_group os_desc_group;
+ struct config_group webusb_group;
struct mutex lock;
struct usb_gadget_strings *gstrings[MAX_USB_STRING_LANGS + 1];
@@ -50,6 +51,11 @@ struct gadget_info {
bool use_os_desc;
char b_vendor_code;
char qw_sign[OS_STRING_QW_SIGN_LEN];
+ bool use_webusb;
+ u16 bcd_webusb_version;
+ u8 b_webusb_vendor_code;
+ char landing_page[255];
+
spinlock_t spinlock;
bool unbind;
};
@@ -780,6 +786,131 @@ static void gadget_strings_attr_release(struct config_item *item)
USB_CONFIG_STRING_RW_OPS(gadget_strings);
USB_CONFIG_STRINGS_LANG(gadget_strings, gadget_info);
+static inline struct gadget_info *webusb_item_to_gadget_info(
+ struct config_item *item)
+{
+ return container_of(to_config_group(item),
+ struct gadget_info, webusb_group);
+}
+
+static ssize_t webusb_use_show(struct config_item *item, char *page)
+{
+ return sysfs_emit(page, "%d\n",
+ webusb_item_to_gadget_info(item)->use_webusb);
+}
+
+static ssize_t webusb_use_store(struct config_item *item, const char *page,
+ size_t len)
+{
+ struct gadget_info *gi = webusb_item_to_gadget_info(item);
+ int ret;
+ bool use;
+
+ mutex_lock(&gi->lock);
+ ret = kstrtobool(page, &use);
+ if (!ret) {
+ gi->use_webusb = use;
+ ret = len;
+ }
+ mutex_unlock(&gi->lock);
+
+ return ret;
+}
+
+static ssize_t webusb_bcdVersion_show(struct config_item *item, char *page)
+{
+ return sysfs_emit(page, "0x%04x\n",
+ webusb_item_to_gadget_info(item)->bcd_webusb_version);
+}
+
+static ssize_t webusb_bcdVersion_store(struct config_item *item,
+ const char *page, size_t len)
+{
+ struct gadget_info *gi = webusb_item_to_gadget_info(item);
+ u16 bcdVersion;
+ int ret;
+
+ mutex_lock(&gi->lock);
+ ret = kstrtou16(page, 0, &bcdVersion);
+ if (ret)
+ goto out;
+ ret = is_valid_bcd(bcdVersion);
+ if (ret)
+ goto out;
+
+ gi->bcd_webusb_version = bcdVersion;
+ ret = len;
+
+out:
+ mutex_unlock(&gi->lock);
+
+ return ret;
+}
+
+static ssize_t webusb_bVendorCode_show(struct config_item *item, char *page)
+{
+ return sysfs_emit(page, "0x%02x\n",
+ webusb_item_to_gadget_info(item)->b_webusb_vendor_code);
+}
+
+static ssize_t webusb_bVendorCode_store(struct config_item *item,
+ const char *page, size_t len)
+{
+ struct gadget_info *gi = webusb_item_to_gadget_info(item);
+ int ret;
+ u8 b_vendor_code;
+
+ mutex_lock(&gi->lock);
+ ret = kstrtou8(page, 0, &b_vendor_code);
+ if (!ret) {
+ gi->b_webusb_vendor_code = b_vendor_code;
+ ret = len;
+ }
+ mutex_unlock(&gi->lock);
+
+ return ret;
+}
+
+static ssize_t webusb_landingPage_show(struct config_item *item, char *page)
+{
+ return sysfs_emit(page, "%s\n", webusb_item_to_gadget_info(item)->landing_page);
+}
+
+static ssize_t webusb_landingPage_store(struct config_item *item, const char *page,
+ size_t len)
+{
+ struct gadget_info *gi = webusb_item_to_gadget_info(item);
+ int l;
+
+ l = min(len, sizeof(gi->landing_page));
+ if (page[l - 1] == '\n')
+ --l;
+
+ mutex_lock(&gi->lock);
+ memcpy(gi->landing_page, page, l);
+ mutex_unlock(&gi->lock);
+
+ return len;
+}
+
+CONFIGFS_ATTR(webusb_, use);
+CONFIGFS_ATTR(webusb_, bVendorCode);
+CONFIGFS_ATTR(webusb_, bcdVersion);
+CONFIGFS_ATTR(webusb_, landingPage);
+
+static struct configfs_attribute *webusb_attrs[] = {
+ &webusb_attr_use,
+ &webusb_attr_bcdVersion,
+ &webusb_attr_bVendorCode,
+ &webusb_attr_landingPage,
+ NULL,
+};
+
+static struct config_item_type webusb_type = {
+ .ct_attrs = webusb_attrs,
+ .ct_owner = THIS_MODULE,
+};
+
static inline struct gadget_info *os_desc_item_to_gadget_info(
struct config_item *item)
{
@@ -1341,6 +1472,16 @@ static int configfs_composite_bind(struct usb_gadget *gadget,
gi->cdev.desc.iSerialNumber = s[USB_GADGET_SERIAL_IDX].id;
}
+ if (gi->use_webusb) {
+ cdev->use_webusb = true;
+ cdev->bcd_webusb_version = gi->bcd_webusb_version;
+ cdev->b_webusb_vendor_code = gi->b_webusb_vendor_code;
+ memcpy(cdev->landing_page, gi->landing_page,
+ strnlen(gi->landing_page,
+ min(sizeof(cdev->landing_page),
+ sizeof(gi->landing_page))));
+ }
+
if (gi->use_os_desc) {
cdev->use_os_string = true;
cdev->b_vendor_code = gi->b_vendor_code;
@@ -1605,6 +1746,10 @@ static struct config_group *gadgets_make(
&os_desc_type);
configfs_add_default_group(&gi->os_desc_group, &gi->group);
+ config_group_init_type_name(&gi->webusb_group, "webusb",
+ &webusb_type);
+ configfs_add_default_group(&gi->webusb_group, &gi->group);
+
gi->composite.bind = configfs_do_nothing;
gi->composite.unbind = configfs_do_nothing;
gi->composite.suspend = NULL;
@@ -474,6 +474,12 @@ struct usb_composite_dev {
struct usb_configuration *os_desc_config;
unsigned int use_os_string:1;
+ /* WebUSB */
+ u16 bcd_webusb_version;
+ u8 b_webusb_vendor_code;
+ char landing_page[255];
+ unsigned int use_webusb:1;
+
/* private: */
/* internals */
unsigned int suspended:1;
@@ -947,6 +947,39 @@ struct usb_ss_container_id_descriptor {
#define USB_DT_USB_SS_CONTN_ID_SIZE 20
+/*
+ * Platform Device Capability descriptor: Defines platform specific device
+ * capabilities
+ */
+#define USB_PLAT_DEV_CAP_TYPE 5
+struct usb_plat_dev_cap_descriptor {
+ __u8 bLength;
+ __u8 bDescriptorType;
+ __u8 bDevCapabilityType;
+ __u8 bReserved;
+ __u8 UUID[16];
+} __attribute__((packed));
+
+#define USB_DT_USB_PLAT_DEV_CAP_SIZE 20
+
+/*
+ * WebUSB Platform Capability descriptor: A device announces support for the
+ * WebUSB command set by including the following Platform Descriptor in its
+ * Binary Object Store
+ * https://wicg.github.io/webusb/#webusb-platform-capability-descriptor
+ */
+struct usb_webusb_cap_descriptor {
+ __u8 bLength;
+ __u8 bDescriptorType;
+ __u8 bDevCapabilityType;
+ __u8 bReserved;
+ __u8 UUID[16];
+ __u16 bcdVersion;
+ __u8 bVendorCode;
+ __u8 iLandingPage;
+} __attribute__((packed));
+#define USB_DT_WEBUSB_SIZE (USB_DT_USB_PLAT_DEV_CAP_SIZE + 4)
+
/*
* SuperSpeed Plus USB Capability descriptor: Defines the set of
* SuperSpeed Plus USB specific device level capabilities