If we have multiple instances of hid function, each of them may have different report descriptor, also their length may be different.
Currently we are using static hidg_desc varable which is being filled in hidg_bind(). Then we send its content to host in hidg_setup() function. This content may have been already overwriten if another instance has executed hidg_bind(). Signed-off-by: Krzysztof Opasiak <[email protected]> --- drivers/usb/gadget/function/f_hid.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/drivers/usb/gadget/function/f_hid.c b/drivers/usb/gadget/function/f_hid.c index a2612fb..eeb2dc2 100644 --- a/drivers/usb/gadget/function/f_hid.c +++ b/drivers/usb/gadget/function/f_hid.c @@ -437,12 +437,20 @@ static int hidg_setup(struct usb_function *f, | USB_REQ_GET_DESCRIPTOR): switch (value >> 8) { case HID_DT_HID: + { + struct hid_descriptor hidg_desc_copy = hidg_desc; + VDBG(cdev, "USB_REQ_GET_DESCRIPTOR: HID\n"); + hidg_desc_copy.desc[0].bDescriptorType = HID_DT_REPORT; + hidg_desc_copy.desc[0].wDescriptorLength = + cpu_to_le16(hidg->report_desc_length); + length = min_t(unsigned short, length, - hidg_desc.bLength); - memcpy(req->buf, &hidg_desc, length); + hidg_desc_copy.bLength); + memcpy(req->buf, &hidg_desc_copy, length); goto respond; break; + } case HID_DT_REPORT: VDBG(cdev, "USB_REQ_GET_DESCRIPTOR: REPORT\n"); length = min_t(unsigned short, length, @@ -632,6 +640,10 @@ static int hidg_bind(struct usb_configuration *c, struct usb_function *f) hidg_fs_in_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length); hidg_hs_out_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length); hidg_fs_out_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length); + /* + * We can use hidg_desc struct here but we should not relay + * that its content won't change after returning from this function. + */ hidg_desc.desc[0].bDescriptorType = HID_DT_REPORT; hidg_desc.desc[0].wDescriptorLength = cpu_to_le16(hidg->report_desc_length); -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
