USB: gadget: add HID gadget driver
g_hid is a USB gadget driver implementing the Human Interface Device class
specification. The driver handles basic HID protocol handling in the
kernel, and allows userspace to read/write HID reports trough /dev/hidgX
character devices.
Signed-off-by: Fabien Chouteau <fabien.chouteau@barco.com>
Signed-off-by: Peter Korsgaard <peter.korsgaard@barco.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/gadget/hid.c b/drivers/usb/gadget/hid.c
new file mode 100644
index 0000000..b77e977
--- /dev/null
+++ b/drivers/usb/gadget/hid.c
@@ -0,0 +1,288 @@
+/*
+ * hid.c -- HID Composite driver
+ *
+ * Based on multi.c
+ *
+ * Copyright (C) 2010 Fabien Chouteau <fabien.chouteau@barco.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/list.h>
+
+#define DRIVER_DESC "HID Gadget"
+#define DRIVER_VERSION "2010/03/16"
+
+/*-------------------------------------------------------------------------*/
+
+#define HIDG_VENDOR_NUM 0x0525 /* XXX NetChip */
+#define HIDG_PRODUCT_NUM 0xa4ac /* Linux-USB HID gadget */
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * kbuild is not very cooperative with respect to linking separately
+ * compiled library objects into one module. So for now we won't use
+ * separate compilation ... ensuring init/exit sections work to shrink
+ * the runtime footprint, and giving us at least some parts of what
+ * a "gcc --combine ... part1.c part2.c part3.c ... " build would.
+ */
+
+#include "composite.c"
+#include "usbstring.c"
+#include "config.c"
+#include "epautoconf.c"
+
+#include "f_hid.c"
+
+
+struct hidg_func_node {
+ struct list_head node;
+ struct hidg_func_descriptor *func;
+};
+
+static LIST_HEAD(hidg_func_list);
+
+/*-------------------------------------------------------------------------*/
+
+static struct usb_device_descriptor device_desc = {
+ .bLength = sizeof device_desc,
+ .bDescriptorType = USB_DT_DEVICE,
+
+ .bcdUSB = cpu_to_le16(0x0200),
+
+ /* .bDeviceClass = USB_CLASS_COMM, */
+ /* .bDeviceSubClass = 0, */
+ /* .bDeviceProtocol = 0, */
+ .bDeviceClass = 0xEF,
+ .bDeviceSubClass = 2,
+ .bDeviceProtocol = 1,
+ /* .bMaxPacketSize0 = f(hardware) */
+
+ /* Vendor and product id can be overridden by module parameters. */
+ .idVendor = cpu_to_le16(HIDG_VENDOR_NUM),
+ .idProduct = cpu_to_le16(HIDG_PRODUCT_NUM),
+ /* .bcdDevice = f(hardware) */
+ /* .iManufacturer = DYNAMIC */
+ /* .iProduct = DYNAMIC */
+ /* NO SERIAL NUMBER */
+ .bNumConfigurations = 1,
+};
+
+static struct usb_otg_descriptor otg_descriptor = {
+ .bLength = sizeof otg_descriptor,
+ .bDescriptorType = USB_DT_OTG,
+
+ /* REVISIT SRP-only hardware is possible, although
+ * it would not be called "OTG" ...
+ */
+ .bmAttributes = USB_OTG_SRP | USB_OTG_HNP,
+};
+
+static const struct usb_descriptor_header *otg_desc[] = {
+ (struct usb_descriptor_header *) &otg_descriptor,
+ NULL,
+};
+
+
+/* string IDs are assigned dynamically */
+
+#define STRING_MANUFACTURER_IDX 0
+#define STRING_PRODUCT_IDX 1
+
+static char manufacturer[50];
+
+static struct usb_string strings_dev[] = {
+ [STRING_MANUFACTURER_IDX].s = manufacturer,
+ [STRING_PRODUCT_IDX].s = DRIVER_DESC,
+ { } /* end of list */
+};
+
+static struct usb_gadget_strings stringtab_dev = {
+ .language = 0x0409, /* en-us */
+ .strings = strings_dev,
+};
+
+static struct usb_gadget_strings *dev_strings[] = {
+ &stringtab_dev,
+ NULL,
+};
+
+
+
+/****************************** Configurations ******************************/
+
+static int __init do_config(struct usb_configuration *c)
+{
+ struct hidg_func_node *e;
+ int func = 0, status = 0;
+
+ if (gadget_is_otg(c->cdev->gadget)) {
+ c->descriptors = otg_desc;
+ c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
+ }
+
+ list_for_each_entry(e, &hidg_func_list, node) {
+ status = hidg_bind_config(c, e->func, func++);
+ if (status)
+ break;
+ }
+
+ return status;
+}
+
+static struct usb_configuration config_driver = {
+ .label = "HID Gadget",
+ .bind = do_config,
+ .bConfigurationValue = 1,
+ /* .iConfiguration = DYNAMIC */
+ .bmAttributes = USB_CONFIG_ATT_SELFPOWER,
+};
+
+/****************************** Gadget Bind ******************************/
+
+static int __init hid_bind(struct usb_composite_dev *cdev)
+{
+ struct usb_gadget *gadget = cdev->gadget;
+ struct list_head *tmp;
+ int status, gcnum, funcs = 0;
+
+ list_for_each(tmp, &hidg_func_list)
+ funcs++;
+
+ if (!funcs)
+ return -ENODEV;
+
+ /* set up HID */
+ status = ghid_setup(cdev->gadget, funcs);
+ if (status < 0)
+ return status;
+
+ gcnum = usb_gadget_controller_number(gadget);
+ if (gcnum >= 0)
+ device_desc.bcdDevice = cpu_to_le16(0x0300 | gcnum);
+ else
+ device_desc.bcdDevice = cpu_to_le16(0x0300 | 0x0099);
+
+
+ /* Allocate string descriptor numbers ... note that string
+ * contents can be overridden by the composite_dev glue.
+ */
+
+ /* device descriptor strings: manufacturer, product */
+ snprintf(manufacturer, sizeof manufacturer, "%s %s with %s",
+ init_utsname()->sysname, init_utsname()->release,
+ gadget->name);
+ status = usb_string_id(cdev);
+ if (status < 0)
+ return status;
+ strings_dev[STRING_MANUFACTURER_IDX].id = status;
+ device_desc.iManufacturer = status;
+
+ status = usb_string_id(cdev);
+ if (status < 0)
+ return status;
+ strings_dev[STRING_PRODUCT_IDX].id = status;
+ device_desc.iProduct = status;
+
+ /* register our configuration */
+ status = usb_add_config(cdev, &config_driver);
+ if (status < 0)
+ return status;
+
+ dev_info(&gadget->dev, DRIVER_DESC ", version: " DRIVER_VERSION "\n");
+
+ return 0;
+}
+
+static int __exit hid_unbind(struct usb_composite_dev *cdev)
+{
+ ghid_cleanup();
+ return 0;
+}
+
+static int __init hidg_plat_driver_probe(struct platform_device *pdev)
+{
+ struct hidg_func_descriptor *func = pdev->dev.platform_data;
+ struct hidg_func_node *entry;
+
+ if (!func) {
+ dev_err(&pdev->dev, "Platform data missing\n");
+ return -ENODEV;
+ }
+
+ entry = kzalloc(sizeof(*entry), GFP_KERNEL);
+ if (!entry)
+ return -ENOMEM;
+
+ entry->func = func;
+ list_add_tail(&entry->node, &hidg_func_list);
+
+ return 0;
+}
+
+static int __devexit hidg_plat_driver_remove(struct platform_device *pdev)
+{
+ struct hidg_func_node *e, *n;
+
+ list_for_each_entry_safe(e, n, &hidg_func_list, node) {
+ list_del(&e->node);
+ kfree(e);
+ }
+
+ return 0;
+}
+
+
+/****************************** Some noise ******************************/
+
+
+static struct usb_composite_driver hidg_driver = {
+ .name = "g_hid",
+ .dev = &device_desc,
+ .strings = dev_strings,
+ .bind = hid_bind,
+ .unbind = __exit_p(hid_unbind),
+};
+
+static struct platform_driver hidg_plat_driver = {
+ .remove = __devexit_p(hidg_plat_driver_remove),
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = "hidg",
+ },
+};
+
+
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_AUTHOR("Fabien Chouteau, Peter Korsgaard");
+MODULE_LICENSE("GPL");
+
+static int __init hidg_init(void)
+{
+ platform_driver_probe(&hidg_plat_driver, hidg_plat_driver_probe);
+ return usb_composite_register(&hidg_driver);
+}
+module_init(hidg_init);
+
+static void __exit hidg_cleanup(void)
+{
+ platform_driver_unregister(&hidg_plat_driver);
+ usb_composite_unregister(&hidg_driver);
+}
+module_exit(hidg_cleanup);