On Wed, Feb 15, 2023 at 11:05:58AM +1000, David Sands wrote:
> Add the ability for FunctionFS driver to be able to create DFU Run-Time
> descriptors.
>
> Signed-off-by: David Sands <david.sands@xxxxxxxxx>
> ---
> drivers/usb/gadget/function/f_fs.c | 12 ++++++++++--
> include/uapi/linux/usb/ch9.h | 4 ++++
> include/uapi/linux/usb/functionfs.h | 10 ++++++++++
> 3 files changed, 24 insertions(+), 2 deletions(-)
Ah, DFU, bad memories (hint, my name is on that spec...)
Why is this a RFC? What needs to be done on this to make it "real"?
>
> diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c
> index 73dc10a77cde..ac77ded9e6ad 100644
> --- a/drivers/usb/gadget/function/f_fs.c
> +++ b/drivers/usb/gadget/function/f_fs.c
> @@ -2049,7 +2049,7 @@ typedef int (*ffs_os_desc_callback)(enum ffs_os_desc_type entity,
>
> static int __must_check ffs_do_single_desc(char *data, unsigned len,
> ffs_entity_callback entity,
> - void *priv, int *current_class)
> + void *priv, int *current_class, int *current_subclass)
> {
> struct usb_descriptor_header *_ds = (void *)data;
> u8 length;
> @@ -2108,6 +2108,7 @@ static int __must_check ffs_do_single_desc(char *data, unsigned len,
> if (ds->iInterface)
> __entity(STRING, ds->iInterface);
> *current_class = ds->bInterfaceClass;
> + *current_subclass = ds->bInterfaceSubClass;
> }
> break;
>
> @@ -2132,6 +2133,12 @@ static int __must_check ffs_do_single_desc(char *data, unsigned len,
> if (length != sizeof(struct ccid_descriptor))
> goto inv_length;
> break;
> + } else if (*current_class == USB_CLASS_APP_SPEC &&
> + *current_subclass == USB_SUBCLASS_DFU) {
> + pr_vdebug("dfu functional descriptor\n");
> + if (length != sizeof(struct usb_dfu_functional_descriptor))
> + goto inv_length;
> + break;
> } else {
> pr_vdebug("unknown descriptor: %d for class %d\n",
> _ds->bDescriptorType, *current_class);
> @@ -2194,6 +2201,7 @@ static int __must_check ffs_do_descs(unsigned count, char *data, unsigned len,
> const unsigned _len = len;
> unsigned long num = 0;
> int current_class = -1;
> + int current_subclass = -1;
>
> ENTER();
>
> @@ -2215,7 +2223,7 @@ static int __must_check ffs_do_descs(unsigned count, char *data, unsigned len,
> return _len - len;
>
> ret = ffs_do_single_desc(data, len, entity, priv,
> - ¤t_class);
> + ¤t_class, ¤t_subclass);
> if (ret < 0) {
> pr_debug("%s returns %d\n", __func__, ret);
> return ret;
> diff --git a/include/uapi/linux/usb/ch9.h b/include/uapi/linux/usb/ch9.h
> index 31fcfa084e63..4683b3b508c7 100644
> --- a/include/uapi/linux/usb/ch9.h
> +++ b/include/uapi/linux/usb/ch9.h
> @@ -266,6 +266,9 @@ struct usb_ctrlrequest {
> /* From the USB 3.1 spec */
> #define USB_DT_SSP_ISOC_ENDPOINT_COMP 0x31
>
> +/* From USB Device Firmware Upgrade Specification, Revision 1.1 */
> +#define USB_DT_DFU_FUNCTIONAL 0x21
> +
> /* Conventional codes for class-specific descriptors. The convention is
> * defined in the USB "Common Class" Spec (3.11). Individual class specs
> * are authoritative for their usage, not the "common class" writeup.
> @@ -335,6 +338,7 @@ struct usb_device_descriptor {
> #define USB_CLASS_VENDOR_SPEC 0xff
>
> #define USB_SUBCLASS_VENDOR_SPEC 0xff
> +#define USB_SUBCLASS_DFU 0x01
>
> /*-------------------------------------------------------------------------*/
>
> diff --git a/include/uapi/linux/usb/functionfs.h b/include/uapi/linux/usb/functionfs.h
> index d77ee6b65328..3d15b193b260 100644
> --- a/include/uapi/linux/usb/functionfs.h
> +++ b/include/uapi/linux/usb/functionfs.h
> @@ -37,6 +37,16 @@ struct usb_endpoint_descriptor_no_audio {
> __u8 bInterval;
> } __attribute__((packed));
>
> +/* DFU Functional descriptor */
> +struct usb_dfu_functional_descriptor {
> + __u8 bLength;
> + __u8 bDescriptorType;
> + __u8 bmAttributes;
Did you forget bEndpointAddress?
I can't remember if that is needed or not, but without it, it's an odd
layout of this structure.
thanks,
greg k-h
