drivers/usb/gadget/legacy/hid.c

   1 /*
   2  * hid.c -- HID Composite driver
   3  *
   4  * Based on multi.c
   5  *
   6  * Copyright (C) 2010 Fabien Chouteau <fabien.chouteau@barco.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  */
  13
  14
  15 #include <linux/kernel.h>
  16 #include <linux/platform_device.h>
  17 #include <linux/list.h>
  18 #include <linux/module.h>
  19 #include <linux/usb/composite.h>
  20 #include <linux/usb/g_hid.h>
  21
  22 #define DRIVER_DESC             "HID Gadget"
  23 #define DRIVER_VERSION          "2010/03/16"
  24
  25 #include "u_hid.h"
  26
  27 /*-------------------------------------------------------------------------*/
  28
  29 #define HIDG_VENDOR_NUM         0x0525  /* XXX NetChip */
  30 #define HIDG_PRODUCT_NUM        0xa4ac  /* Linux-USB HID gadget */
  31
  32 /*-------------------------------------------------------------------------*/
  33
  34 struct hidg_func_node {
  35         struct usb_function_instance *fi;
  36         struct usb_function *f;
  37         struct list_head node;
  38         struct hidg_func_descriptor *func;
  39 };
  40
  41 static LIST_HEAD(hidg_func_list);
  42
  43 /*-------------------------------------------------------------------------*/
  44 USB_GADGET_COMPOSITE_OPTIONS();
  45
  46 static struct usb_device_descriptor device_desc = {
  47         .bLength =              sizeof device_desc,
  48         .bDescriptorType =      USB_DT_DEVICE,
  49
  50         .bcdUSB =               cpu_to_le16(0x0200),
  51
  52         /* .bDeviceClass =              USB_CLASS_COMM, */
  53         /* .bDeviceSubClass =   0, */
  54         /* .bDeviceProtocol =   0, */
  55         .bDeviceClass =         USB_CLASS_PER_INTERFACE,
  56         .bDeviceSubClass =      0,
  57         .bDeviceProtocol =      0,
  58         /* .bMaxPacketSize0 = f(hardware) */
  59
  60         /* Vendor and product id can be overridden by module parameters.  */
  61         .idVendor =             cpu_to_le16(HIDG_VENDOR_NUM),
  62         .idProduct =            cpu_to_le16(HIDG_PRODUCT_NUM),
  63         /* .bcdDevice = f(hardware) */
  64         /* .iManufacturer = DYNAMIC */
  65         /* .iProduct = DYNAMIC */
  66         /* NO SERIAL NUMBER */
  67         .bNumConfigurations =   1,
  68 };
  69
  70 static const struct usb_descriptor_header *otg_desc[2];
  71
  72 /* string IDs are assigned dynamically */
  73 static struct usb_string strings_dev[] = {
  74         [USB_GADGET_MANUFACTURER_IDX].s = "",
  75         [USB_GADGET_PRODUCT_IDX].s = DRIVER_DESC,
  76         [USB_GADGET_SERIAL_IDX].s = "",
  77         {  } /* end of list */
  78 };
  79
  80 static struct usb_gadget_strings stringtab_dev = {
  81         .language       = 0x0409,       /* en-us */
  82         .strings        = strings_dev,
  83 };
  84
  85 static struct usb_gadget_strings *dev_strings[] = {
  86         &stringtab_dev,
  87         NULL,
  88 };
  89
  90
  91
  92 /****************************** Configurations ******************************/
  93
  94 static int do_config(struct usb_configuration *c)
  95 {
  96         struct hidg_func_node *e, *n;
  97         int status = 0;
  98
  99         if (gadget_is_otg(c->cdev->gadget)) {
 100                 c->descriptors = otg_desc;
 101                 c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
 102         }
 103
 104         list_for_each_entry(e, &hidg_func_list, node) {
 105                 e->f = usb_get_function(e->fi);
 106                 if (IS_ERR(e->f))
 107                         goto put;
 108                 status = usb_add_function(c, e->f);
 109                 if (status < 0) {
 110                         usb_put_function(e->f);
 111                         goto put;
 112                 }
 113         }
 114
 115         return 0;
 116 put:
 117         list_for_each_entry(n, &hidg_func_list, node) {
 118                 if (n == e)
 119                         break;
 120                 usb_remove_function(c, n->f);
 121                 usb_put_function(n->f);
 122         }
 123         return status;
 124 }
 125
 126 static struct usb_configuration config_driver = {
 127         .label                  = "HID Gadget",
 128         .bConfigurationValue    = 1,
 129         /* .iConfiguration = DYNAMIC */
 130         .bmAttributes           = USB_CONFIG_ATT_SELFPOWER,
 131 };
 132
 133 /****************************** Gadget Bind ******************************/
 134
 135 static int hid_bind(struct usb_composite_dev *cdev)
 136 {
 137         struct usb_gadget *gadget = cdev->gadget;
 138         struct list_head *tmp;
 139         struct hidg_func_node *n, *m;
 140         struct f_hid_opts *hid_opts;
 141         int status, funcs = 0;
 142
 143         list_for_each(tmp, &hidg_func_list)
 144                 funcs++;
 145
 146         if (!funcs)
 147                 return -ENODEV;
 148
 149         list_for_each_entry(n, &hidg_func_list, node) {
 150                 n->fi = usb_get_function_instance("hid");
 151                 if (IS_ERR(n->fi)) {
 152                         status = PTR_ERR(n->fi);
 153                         goto put;
 154                 }
 155                 hid_opts = container_of(n->fi, struct f_hid_opts, func_inst);
 156                 hid_opts->subclass = n->func->subclass;
 157                 hid_opts->protocol = n->func->protocol;
 158                 hid_opts->report_length = n->func->report_length;
 159                 hid_opts->report_desc_length = n->func->report_desc_length;
 160                 hid_opts->report_desc = n->func->report_desc;
 161         }
 162
 163
 164         /* Allocate string descriptor numbers ... note that string
 165          * contents can be overridden by the composite_dev glue.
 166          */
 167
 168         status = usb_string_ids_tab(cdev, strings_dev);
 169         if (status < 0)
 170                 goto put;
 171         device_desc.iManufacturer = strings_dev[USB_GADGET_MANUFACTURER_IDX].id;
 172         device_desc.iProduct = strings_dev[USB_GADGET_PRODUCT_IDX].id;
 173
 174         if (gadget_is_otg(gadget) && !otg_desc[0]) {
 175                 struct usb_descriptor_header *usb_desc;
 176
 177                 usb_desc = usb_otg_descriptor_alloc(gadget);
 178                 if (!usb_desc) {
 179                         status = -ENOMEM;
 180                         goto put;
 181                 }
 182                 usb_otg_descriptor_init(gadget, usb_desc);
 183                 otg_desc[0] = usb_desc;
 184                 otg_desc[1] = NULL;
 185         }
 186
 187         /* register our configuration */
 188         status = usb_add_config(cdev, &config_driver, do_config);
 189         if (status < 0)
 190                 goto free_otg_desc;
 191
 192         usb_composite_overwrite_options(cdev, &coverwrite);
 193         dev_info(&gadget->dev, DRIVER_DESC ", version: " DRIVER_VERSION "\n");
 194
 195         return 0;
 196
 197 free_otg_desc:
 198         kfree(otg_desc[0]);
 199         otg_desc[0] = NULL;
 200 put:
 201         list_for_each_entry(m, &hidg_func_list, node) {
 202                 if (m == n)
 203                         break;
 204                 usb_put_function_instance(m->fi);
 205         }
 206         return status;
 207 }
 208
 209 static int hid_unbind(struct usb_composite_dev *cdev)
 210 {
 211         struct hidg_func_node *n;
 212
 213         list_for_each_entry(n, &hidg_func_list, node) {
 214                 usb_put_function(n->f);
 215                 usb_put_function_instance(n->fi);
 216         }
 217
 218         kfree(otg_desc[0]);
 219         otg_desc[0] = NULL;
 220
 221         return 0;
 222 }
 223
 224 static int hidg_plat_driver_probe(struct platform_device *pdev)
 225 {
 226         struct hidg_func_descriptor *func = dev_get_platdata(&pdev->dev);
 227         struct hidg_func_node *entry;
 228
 229         if (!func) {
 230                 dev_err(&pdev->dev, "Platform data missing\n");
 231                 return -ENODEV;
 232         }
 233
 234         entry = kzalloc(sizeof(*entry), GFP_KERNEL);
 235         if (!entry)
 236                 return -ENOMEM;
 237
 238         entry->func = func;
 239         list_add_tail(&entry->node, &hidg_func_list);
 240
 241         return 0;
 242 }
 243
 244 static int hidg_plat_driver_remove(struct platform_device *pdev)
 245 {
 246         struct hidg_func_node *e, *n;
 247
 248         list_for_each_entry_safe(e, n, &hidg_func_list, node) {
 249                 list_del(&e->node);
 250                 kfree(e);
 251         }
 252
 253         return 0;
 254 }
 255
 256
 257 /****************************** Some noise ******************************/
 258
 259
 260 static struct usb_composite_driver hidg_driver = {
 261         .name           = "g_hid",
 262         .dev            = &device_desc,
 263         .strings        = dev_strings,
 264         .max_speed      = USB_SPEED_HIGH,
 265         .bind           = hid_bind,
 266         .unbind         = hid_unbind,
 267 };
 268
 269 static struct platform_driver hidg_plat_driver = {
 270         .remove         = hidg_plat_driver_remove,
 271         .driver         = {
 272                 .name   = "hidg",
 273         },
 274 };
 275
 276
 277 MODULE_DESCRIPTION(DRIVER_DESC);
 278 MODULE_AUTHOR("Fabien Chouteau, Peter Korsgaard");
 279 MODULE_LICENSE("GPL");
 280
 281 static int __init hidg_init(void)
 282 {
 283         int status;
 284
 285         status = platform_driver_probe(&hidg_plat_driver,
 286                                 hidg_plat_driver_probe);
 287         if (status < 0)
 288                 return status;
 289
 290         status = usb_composite_probe(&hidg_driver);
 291         if (status < 0)
 292                 platform_driver_unregister(&hidg_plat_driver);
 293
 294         return status;
 295 }
 296 module_init(hidg_init);
 297
 298 static void __exit hidg_cleanup(void)
 299 {
 300         usb_composite_unregister(&hidg_driver);
 301         platform_driver_unregister(&hidg_plat_driver);
 302 }
 303 module_exit(hidg_cleanup);