A little research on Linux gadget HID device __linux

Above, configure the compile gadget HID module

Build G_hid.ko in Driver/usb/gadget directory after make modules

To execute the load command:

root@xxx:/mnt# insmod G_hid.ko 
insmod:can ' t insert ' G_hid.ko ': No such device

Hint error.

In the TI Technology Forum to see the relevant technical reply:

The error message for you had before ' error inserting ' G_hid.ko ':-1 No such device. ' are due to incomplete hid gadget Driv Er. You can followdocumentation/usb/gadget_hid.txt to add your own platform device portion.

for your reference, the following patch are what I tried and it works with the 3.3 kernel from the link I provided Abov E with SD card boot. Download the mentioned patches

From 6363b29be2c2b477a723b74e52025511be280979 Mon Sep 00:00:00 2001 From:bin Liu <b-liu@ti.com> Date:fri, Ja   N 2013 10:27:57-0600 Subject: [PATCH] patched hid Gadget---drivers/usb/gadget/hid.c | ++++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, insertions (+), 0 deletions (-) diff--git A/drivers /USB/GADGET/HID.C B/DRIVERS/USB/GADGET/HID.C index f888c3e. c037039 100644---a/drivers/usb/gadget/hid.c +++ b/drivers/usb/gadget/hid.c @@ -16,6 +16,8 @@ -16,6 <linux/platfor
 m_device.h> #include <linux/list.h> + #include <linux/usb/g_hid.h> + #define DRIVER_DESC "hid Gadget"
 
#define Driver_version "2010/03/16" @@ -49,6 +51,57 @@ -49,6 hidg_func_node {static list_head (hidg_func_list); + +/* HID Descriptor for a keyboard * * +static struct hidg_func_descriptor = {+. My_hid_data = 0,/* No Subclass S/+ protocol = 1,/* Keyboard/+ Report_length = 8, +. Report_desc_length = =, +. Report_desc = {+ 0x05, 0x01,/* Usage_page (Generic Desktop) * * + 0x09, 0x06,/* USAGE (keyboard) * * + 0XA1, 0x01,/* COLLECTION (Application) * * + 0x05, 0x07,/* usage_page (keyboard) * * + 0x19, 0x E0,/* Usage_minimum (keyboard leftcontrol) * * + 0x29, 0xe7,//* Usage_maximum (keyboard right GUI) * * + 0x15, 0x00	,/* Logical_minimum (0) * * * + 0x25, 0x01,//* Logical_maximum (1) * * + 0x75, 0x01,    /* REPORT_SIZE (1) * * * + 0x95, 0x08,/* REPORT_COUNT (8) * * + 0x81, 0x02,/*   INPUT (data,var,abs)/+ 0x95, 0x01, * report_count (1) * * * + 0x75, 0x08,/* Report_size (8) * * * + 0x81, 0x03,/* INPUT (cnst,var,abs) * * + 0x95, 0x05,/* R Eport_count (5) * * * + 0x75, 0x01, * report_size (1) * * + 0x05, 0x08,/* USA          Ge_page (LEDs)          * * + 0x19, 0x01,/* Usage_minimum (Num Lock) * * * + 0x29, 0x05,//* Usage_maximum (Kana)                     * * + 0x91, 0x02,/* OUTPUT (data,var,abs)/+ 0x95, 0x01,/* Report_count (1)                * * + 0x75, 0x03,/* REPORT_SIZE (3) * * * + 0x91, 0x03,//OUTPUT (Cnst,var,abs)                      * * + 0x95, 0x06,///Report_count (6) * * * + 0x75, 0x08,/* Report_size (8)                * * + 0x15, 0x00,///logical_minimum (0) * * * + 0x25, 0x65,/* Logical_maximum (101) 
* * + 0x05, 0x07, * usage_page (keyboard)/+ 0x19, 0x00,/* Usage_minimum (Reserved) * * 		+ 0x29, 0x65,/* Usage_maximum (keyboard application)/+ 0X81, 0x00,/* INPUT (data,ary,abs) * * +
0XC0/* end_collection * * +} +}; + +static struct Platform_device My_hid = {+. Name = "HIDG", +. id = 0, +. Num_resources = 0, +. Resource = 0, +. Dev.platform_data = &my_hid_data, +}; +/*-------------------------------------------------------------------------/static struct USB_DEVICE_
 
Descriptor Device_desc = {@@ -267,6 +320,13 @@ -267,6 int __init hidg_init (void) {int status;
+ status = Platform_device_register (&my_hid); 
 	+ if (Status < 0) {+ PRINTK ("____ reg failed\n"); + platform_device_unregister (&my_hid); + return status; +} +
 	Status = Platform_driver_probe (&hidg_plat_driver, hidg_plat_driver_probe);
 if (Status < 0) @@ -283,6 +343,7 @@ -283,6 (hidg_init); static void __exit Hidg_cleanup (void) {platform_driver_unregister (&hidg_plat_driver); + Platform_device_
 	Unregister (&my_hid);
 Usb_composite_unregister (&hidg_driver);
} module_exit (Hidg_cleanup);
 --1.7.0.4

Keep trying ...