The current f_hid driver doesn't handle GET_PROCOTOL and
SET_PROCOTOL requests, which are required to operate HID
gadgets in BOOT mode. This patch implements this feature for
devices that have the same implementation for REPORT and BOOT mode
so that these devices are recognized by older BIOSes.
Signed-off-by: Abdulhadi Mohamed <abdulahhadi2@xxxxxxxxx>
---
V4: Replaced patch message to correctly describe changes and
added descriptions about previous revisions
v3: Fixed formatting/whitespace errors using checkpatch.pl
v2: Added HID protocol macros for clarity as per Alan's suggestions
Removed unnessecary code related to remote wakeup call
Removed goto stall for handling set_protocol
---
drivers/usb/gadget/function/f_hid.c | 17 ++++++++++++++++-
include/linux/hid.h | 6 ++++++
2 files changed, 22 insertions(+), 1 deletion(-)
diff --git a/drivers/usb/gadget/function/f_hid.c b/drivers/usb/gadget/function/f_hid.c
index 5eea448..c60b882 100644
--- a/drivers/usb/gadget/function/f_hid.c
+++ b/drivers/usb/gadget/function/f_hid.c
@@ -44,6 +44,7 @@ struct f_hidg {
/* configuration */
unsigned char bInterfaceSubClass;
unsigned char bInterfaceProtocol;
+ unsigned char protocol;
unsigned short report_desc_length;
char *report_desc;
unsigned short report_length;
@@ -527,7 +528,9 @@ static int hidg_setup(struct usb_function *f,
case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
| HID_REQ_GET_PROTOCOL):
VDBG(cdev, "get_protocol\n");
- goto stall;
+ length = min_t(unsigned int, length, 1);
+ ((u8 *) req->buf)[0] = hidg->protocol;
+ goto respond;
break;
case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
@@ -539,6 +542,17 @@ static int hidg_setup(struct usb_function *f,
case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
| HID_REQ_SET_PROTOCOL):
VDBG(cdev, "set_protocol\n");
+ if (value > HID_REPORT_PROTOCOL)
+ goto stall;
+ length = 0;
+ /*
+ * We assume that programs implementing the Boot protocol
+ * are also compatible with the Report Protocol
+ */
+ if (hidg->bInterfaceSubClass == USB_INTERFACE_SUBCLASS_BOOT) {
+ hidg->protocol = value;
+ goto respond;
+ }
goto stall;
break;
@@ -768,6 +782,7 @@ static int hidg_bind(struct usb_configuration *c, struct usb_function *f)
/* set descriptor dynamic values */
hidg_interface_desc.bInterfaceSubClass = hidg->bInterfaceSubClass;
hidg_interface_desc.bInterfaceProtocol = hidg->bInterfaceProtocol;
+ hidg->protocol = HID_REPORT_PROTOCOL;
hidg_ss_in_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
hidg_ss_in_comp_desc.wBytesPerInterval =
cpu_to_le16(hidg->report_length);
diff --git a/include/linux/hid.h b/include/linux/hid.h
index b2ec827..29d06c8 100644
--- a/include/linux/hid.h
+++ b/include/linux/hid.h
@@ -347,6 +347,12 @@ struct hid_item {
#define HID_GROUP_LOGITECH_DJ_DEVICE 0x0102
/*
+ * HID protocol status
+ */
+#define HID_REPORT_PROTOCOL 1
+#define HID_BOOT_PROTOCOL 0
+
+/*
* This is the global environment of the parser. This information is
* persistent for main-items. The global environment can be saved and
* restored with PUSH/POP statements.
--
2.9.3
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